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  • 1
    Publikationsdatum: 2012-02-25
    Beschreibung: A reliable procedure for measuring parameters connected to surface roughness is needed to compare the gas sensing properties of various thin films or the effect of different fabrication procedures on the surface roughness and the sensing properties. In this article, we propose to investigate how the acquisition parameters specific to atomic force microscopy investigations such as pixel size, scan area and scan speed influence the roughness parameters, namely root mean square and surface area ratio, commonly used for characterizing the gas sensing properties of porphyrins and other materials. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.
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  • 2
    Publikationsdatum: 2012-03-15
    Beschreibung: Virus particles and viral inclusions were detected by transmission electron microscopy examination of sections of the seminal vesicles and mucus gland of asymptomatic young drones from colonies of Apis mellifera lightly infested by Varroa mite. In the mucus gland the infection was found in the muscular sheath and epithelium, while in the seminal vesicle in cells of the outer serosa. Isolated viral particles were also observed in the hemolymph occupying the intercellular spaces of the muscular sheath fibers. In the muscle the virus appeared as polygonal crystalloid inclusions, while in the epithelium mainly inside cytoplasmic vesicles. The infected cells apparently are not damaged. The virus particles are present in the hemolymph and forming more mature structures, as crystalloids, in the muscle. This suggests that the virus is liberated in the body fluid and infects the tissues penetrating the cells through endocytosis. The presence of virus in mucus gland epithelial vesicles raise the possibility of its transference to the gland secretion and therefore, to the semen. Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc.
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  • 3
    Publikationsdatum: 2012-03-15
    Beschreibung: The aim of this study was to evaluate the persistence of resin cement residues after dentin surface cleaning with different alcohol-based solutions or an essential oil (eucalyptol). Forty bovine teeth were sectioned in order to expose pulp chamber dentin to be washed with 1.0 mL of 2.5% sodium hypochlorite (NaOCl), followed by 0.1 mL of 17% EDTA application for 3 min, and final irrigation with 2.5% NaOCl. The specimens were air dried and resin-based cement was rubbed onto the dentine surface with a microbrush applicator. After 15 min, the surface was scrubbed with a cotton pellet and moistened with different dentin cleaning solutions, compounding the following groups: G1—95% ethanol, G2—70% ethanol, G3—70% isopropyl alcohol, or G4—eucalyptol. The dentin was scrubbed until the cement residues could not be visually detected. Sections were then processed for SEM and evaluated at ×500 magnification. Scores were attributed to each image according to the area covered by residual sealer, and data were subjected to Kruskal–Wallis at 5% significance. Eucalyptol promoted the most adequate dentin cleaning, although no statistical difference was detected amongst the groups ( P 〉 0.05), except between the eucalyptol and 70% ethanol groups ( P 〈 0.05). All the evaluated dentin cleaning solutions were unable to completely remove the cement residues from the dentin surface. Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc.
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  • 4
    Publikationsdatum: 2012-03-16
    Beschreibung: This study evaluated the effects on human enamel after two bleaching procedures: with a fluoridated bleaching agent and with topical fluoride application postbleaching. It used 43 enamel blocks (3 mm 2 ) that were ground flat (600–2,000 grit) and polished with polishing paste (one and one-fourth). Specimens were randomly divided into three groups according to the bleaching procedure: (1) control group, (2) hydrogen peroxide 35% (HPF) and topical application of fluoride 1.23%, and (3) HP 38% (OP) with fluoride in its composition. Bleaching agents were used according to the manufacturer's instructions. Three methodologies were used: nanoindentation, to observe surface hardness and elastic modulus; atomic force microscopy, to observe surface roughness ( R a − R z ); and scanning electron microscopy, to observe the enamel surface effects. Group OP had a decrease in the elastic modulus after bleaching, which was recovered at 14 days. An increased roughness ( R a ; 32%) was observed on group HPF and had an increased erosion on enamel surface (67%). It was concluded that topical application of fluoride, after using the nonfluoridated whitening agent, increased the roughness values and erosion of enamel. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.
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  • 5
    Publikationsdatum: 2012-03-16
    Beschreibung: Feature/edge-preserving noise removal techniques have a strong potential in several application domains including medical image processing. Magnetic resonance (MR) images have a tendency to gain Rician noise during acquisition. In this article, we have presented genetic algorithms based adapted selective non-local means (GASNLM) filter-based scheme for noise suppression of MR images while preserving the image features as much as possible. We have applied GASNLM filter with optimal parameter values for different frequency image regions to remove the noise. Filter parameter values are optimized by genetic algorithm (GA). A change in NLM filter known as selective weight matrix is also proposed to preserve the image features. The results prove soundness of the method. We have compared results with many well known and latest techniques, and the improvements are discussed. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.
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  • 6
    Publikationsdatum: 2012-03-11
    Beschreibung: OBJECTIVES: The aim of this in vitro study was to investigate the efficacy of in-office bleaching technique combined with the application of a casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) paste (MI Paste–MI) at different moments and its influence on enamel surface properties. METHODS: Eighty bovine dental crowns were randomly allocated into eight groups ( n = 10), and bleached with either 35% hydrogen peroxide (HP) or 37% carbamide peroxide (CP). Four different protocols of application of MI were considered: without MI, MI applied before bleaching, MI applied after bleaching, and MI applied both before and after bleaching. Bleaching effectiveness was measured by the VITA EasyShade spectrophotometer utilizing the CIEL*a*b* system (Δ E , Δ L *, Δ a *, and Δ b *). Color readings were measured at baseline, 7, 14, and 21 days. Hardness and roughness were measured at baseline (T0) and immediately after bleaching (T14). Data were subjected to the two-way ANOVA for repeated measurements and Tukey's test at 5%. RESULTS: HP groups achieved the greatest color change. The application of a CPP-ACP paste did not reduce the efficacy of bleaching peroxides. Samples bleached with CP showed decreased hardness at T14. Samples bleached with HP that received the application of MI before and before/after bleaching did not present hardness decrease at T14. Samples bleached with peroxides only and received MI after bleaching showed increased roughness at T14. CONCLUSIONS: The use of CPP-ACP was able to prevent negative changes in roughness and hardness of bovine enamel when associated to hydrogen peroxide, and might be applied before/after the bleaching protocol. Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc.
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  • 7
    Publikationsdatum: 2012-03-11
    Beschreibung: Ticks are ectoparasites of great medical and veterinary importance around the world and synthetic chemicals such as permethrin have been used for their control. This study provides a cytochemistry analysis of both degenerative and cell death processes in salivary glands of the brown dog tick Rhipicephalus sanguineus semi-engorged females exposed to 206, 1,031, and 2,062 ppm of permethrin. The results presented herein demonstrate that permethrin is a potent chemical acaricide that would act on the glandular tissue's morphophysiology in this tick species by eliciting severe changes in the acinus shape, intense vacuolation of the acinar cells' cytoplasm, marked glandular tissue disorganization, culminating in an advanced degenerative stage with consequent formation of many apoptotic bodies (cell death). In addition, permethrin induced major changes in the acinar cells' nucleus, such as a change both in its shape and size, chromatin marginalization, nuclear fragmentation, and appearance of picnotic nuclei, especially when the highest concentrations of the product were used. Thus, permethrin induced early degeneration of this tissue characterized by significant changes in the structure of acinar cells and production of enzymes related to the cell death process, in addition to interfering directly in the genetic material of these cells. Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc.
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  • 8
    Publikationsdatum: 2012-03-15
    Beschreibung: The pumping organ of blood-sucking female mosquitoes has a three-dimensional (3D) structure. However, conventional two-dimensional imaging methods are insufficient for visualizing the 3D structure in detail. Furthermore, their 3D imaging tasks are highly time consuming and sample preparation process requires elaborate skill. Among 3D imaging techniques, synchrotron X-ray microscopic computed tomography (SR-μCT) is especially suitable for small insects with opaque cuticles, such as mosquitoes. In this study, the 3D morphological structure of the pump system of a female mosquito was visualized using SR-μCT. Expandable volume capacities of two pump chambers were measured for several mosquito samples of similar size. To verify the cross-sectional images acquired by SR-μCT, complementary paraffin-sectioning data were compared. Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc.
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  • 9
    Publikationsdatum: 2012-03-16
    Beschreibung: Frictional interactions between wires and brackets reduce the efficacy in orthodontic treatments. Self-ligating brackets (SLBs) are now more often used due to lower frictional forces when compared with conventional-ligating brackets. In this study, scanning electron microscopy and atomic force microscopy were used to examine the microstructural effects of stainless steel and ceramic SLBs on the surface roughness of stainless steel and superelastic NiTi wires both after in vivo clinical orthodontic treatment as well as in in vitro three-point bending experiments. A combination of two wires—0.019 in. × 0.025 in. stainless steel wires and 0.016 in. superelastic NiTi wires—and two SLBs—both passive-type stainless steel SLBs and active-type ceramic SLBs—was applied for 4 months (bicuspid-extraction) in an in vivo setting and for 1 month in an in vitro setting (200 g loads). After the SLB treatments, all wires exhibited severe scratches secondary to frictional interactions with the brackets. When used with the stainless steel SLBs (Damon 3MX®), the surfaces of 0.019 in. × 0.025 in. stainless steel ( P 〈 0.0001) and 0.016 in. superelastic NiTi wires ( P 〈 0.05) were significantly smoother than when used with the ceramic SLBs (Clippy-C®). Such results suggest that orthodontic treatments with stainless steel SLBs are more effective than with ceramic SLBs. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.
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  • 10
    Publikationsdatum: 2012-03-16
    Beschreibung: To determine whether sodium hypochlorite (NaOCl) with 0.2% chlorhexidine gluconate (CHX) leads to colour change and precipitate formation, and to ultrastructurally analyse the dentine surface after simultaneous irrigation with 0.5% NaOCl and 0.2% CHX. Four tubes in which 5ml of different NaOCl concentrations and 5ml 0,2% CHX were placed, were observed every 15 minutes in the first two hours and after 7 days. Mixture solutions were centrifuged at 800 rpm/4 min. A precipitate is observed under light-microscopy. Thirty-five single-rooted teeth were instrumented using crown-down technique with irrigation: Positive control: distilled water, Negative control: 0,5% NaOCl+15% EDTA, Experimental group: identical to the negative control, then canals were treated with 0.5% NaOCl+0.2% CHX. The longitudinal root sections were observed under scanning-electron-microscopy. The amount of debris was assessed with 5/score-system, and the results were analysed using the Mann-Whitney U test (p 〈 0.001). Change in colour was noticed immediately after the merger and it did not change with time. Mixture solutions showed considerable turbidity, but precipitate was observed only after centrifugation. Statistical analysis showed a significant difference in the dentinal wall purity when comparing the cervical and middle root canal thirds between the experimental and negative control group. The difference was also observed between the cervical and middle thirds compared to the apical third of the root canal within these groups. Interaction between NaOCl and CHX, as well as the creation of precipitates, depends not only on the concentration of NaOCl, but also on the concentration of CHX. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.
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  • 11
    Publikationsdatum: 2012-03-16
    Beschreibung: Leafcutter ants of the genus Atta Fabricius are serious agricultural pests. Morphological studies of immature stages within this group are few, and the data provided for species of considerable importance are usually incomplete. In this study, the immatures of Atta sexdens Linnaeus are described and compared using light and scanning electron microscopy. Only specimens from founding stage colonies (i.e., lacking adult workers) were used. The existence of four larval instars was estimated by a frequency plot of maximum head widths, and the larvae of different instars differed from each other mainly by their bodily dimensions. Worker larvae belonged to two distinct morphological castes: (1) gardeners and nurses and (2) within-nest generalists. The worker larvae described in this study differed from a previous description of the same species by the following traits: the existence of a genal lobe, the number of clypeal hairs, the presence of two hairs on the ninth abdominal somite, the presence of hairs on the anterior surface of the labrum, and the shape of the maxillary palpus. This study provides a comparative analysis of immature stages of A. sexdens that may be relevant to future morphological and biological studies of the Attini. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.
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  • 12
    Publikationsdatum: 2012-12-29
    Beschreibung: ABSTRACT Microstructure of gelatin particles played a key role in determining the physicochemical properties of gelatin. Ionic strength and pH as systematic manners were considered to affect gelatin particles structure on the micrometer scale. Scanning electron microscopy was used for depicting the morphologies of gelatin particles. Increasing pH to 10.0 or decreasing pH to 4.0, spherical, spindle, and irregular aggregates of gelatin particles at 2, 6, 10, and 14% solution (w/w) were all transformed to spindle aggregates. When NaCl was added to the system, the molecular chains of gelatin possibly rearranged themselves in a stretched state, and the ribbon aggregates was observed. The structural transitions of gelatin aggregates were strongly depended on the electrostatic repulsion. In the gelatin–sodium dodecyl sulfate (SDS) case, the micrometer scale of aggregates was larger and the different degrees of cross-links were induced through hydrophobic interaction and electrostatic repulsion. Microsc. Res. Tech., 2012 . © 2012 Wiley Periodicals, Inc.
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  • 13
    Publikationsdatum: 2012-12-29
    Beschreibung: Purpose: Till date there is no exclusive marker for human corneal epithelial stem cells (CESCs). In this study, our strategy is to combine high expression of ABCG2, a putative SC marker with high N/C ratio to develop a specific method for identification of CESCs. Methods Limbal/corneal epithelial cells (LECs/CECs) were isolated from cadaver eyes by enzymatic treatment and the cytospin smears/cryosections were immunostained for ABCG2, p63, or connexin-43 (Cx-43) and counterstained with propidium iodide/DAPI. Analysis was carried out for (1) ABCG2 expression, N/C ratio, (2) p63, ABCG2, N/C ratio, and (3) ABCG2, Cx-43, N/C ratio using confocal/fluorescence microscopy. Results ABCG2 was highly expressed by cells in the basal and suprabasal layers of limbus. The SCs identified on the basis of our earlier method using high levels of p63 expression along with high (〉0.7) N/C ratio were strongly positive for ABCG2 and negative for differentiation marker Cx-43. High expression of ABCG2 was also observed in cells with high p63 expression and low (〈0.7) N/C ratio; however, they were positive for Cx-43. Combining high ABCG2 expression with large N/C ratio in fluorescence microscopy identified 5.3 ± 3.5% LECs as putative SCs and this was confirmed by confocal microscopic analysis. Conclusions We demonstrate the importance of combining ABCG2 expression with N/C ratio for identification and quantification of human CESCs. This method will have application in evaluating the role of niche cells/factors in the maintenance of stemness. Microsc. Res. Tech., 2012 . © 2012 Wiley Periodicals, Inc.
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  • 14
    Publikationsdatum: 2012-11-10
    Beschreibung: To well enhance the mineral image and image details obtained by microscopes, an effective mineral image enhancement algorithm through feature extraction using the morphological center operator is proposed in this work. First, mineral image feature extraction based on the morphological center operator is proposed and discussed. Second, the multiscale extension of the mineral image feature extraction is given by using the multiscale structuring elements. Third, the important mineral image features at multiscales of image are extracted and used to construct the final mineral features for mineral image enhancement. Finally, the original mineral image is well enhanced through importing the extracted final mineral image features into the original mineral image. Experimental results on different types of microscopy images of minerals verified the effective performance of the proposed algorithm for microscopy mineral image enhancement. Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc.
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  • 15
    Publikationsdatum: 2012-09-29
    Beschreibung: Analysis of the cellular distributions of coenzymes including NADH may aid in understanding a cells metabolic status. We altered serum concentration (0, 2, and 10%) to induce living myoblast cells to undergo the early stages of differentiation. Through microscopy and phasor-FLIM, we spatially mapped and identified variations in the distribution of free and bound NADH. Undifferentiated cells displayed abundant free NADH within the nucleus along with specific regions of more bound NADH. Complete serum starvation dramatically increased the fraction of bound NADH in the nucleus, indicating heightened requirement for transcriptional processes. In comparison, cells exposed to 2% serum exhibited intermediate free nuclear NADH fraction. Overall our results suggest an order of events in which a cell metabolic status alters significantly during the early stages of serum induced differentiation. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.
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  • 16
    Publikationsdatum: 2012-10-04
    Beschreibung: This article presents the SEM-EDX and microFTIR study and the corrosion behavior of new five types of phosphated coatings obtained by coprecipitation in acid aqueous medium of some metal cations, pursuing the influence of the addition of other cations and a moderator of precipitation, on the uniformity and compactness of the layers and on the morphology of dendritic structure of Zn(II) and Fe(II) phosphates. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.
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  • 17
    Publikationsdatum: 2012-10-05
    Beschreibung: Because of the limitations of the X-ray hardware systems in mammogram machines, the quality of the breast mammogram images may undergo from poor resolution or low contrast. Quantum noise occurs in the mammogram images during acquisition due to low-count X-ray photons. In this work, an adaptive frost filter has been used to remove quantum noise. Local binary patterns have been extracted to classify breast mammograms into benign and malignant using different classifiers. Results show the superiority of the proposed algorithm in terms of sensitivity, specificity, and accuracy. Mammographic Institute Society Analysis database of mammography has been used for experimentation. Peak signal-to-noise ratio and structural similarity index measure are used to test the validity of adaptive frost filter. Experiment results show that proposed technique produces better results. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.
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  • 18
    Publikationsdatum: 2012-07-14
    Beschreibung: The knowledge of the process of egg formation is indispensable for understanding the mechanisms involved in the reproduction of different species. In this context, the objective of this work was to describe the ultrastructure of the oocytes of Urostreptus atrobrunneus (Spirostreptida), a potential plague of urban centers in different locations of São Paulo State. The lack of knowledge about the morphology, physiology, and the reproductive behavior of the species have hindered an effective control of it. The oocytes of U. atrobrunneus presented three development stages: young oocyte or type I; intermediary oocyte or type II; and mature oocyte or type III. During the oocyte development, the cytoplasm become filled with several globules of protein, drops of lipids, and sphaerocrystals, and it was not observed in many organelles in the oocytes with exception of mitochondria, abundant, principally in young oocytes. The vitelline membrane is also deposited in a discontinuous form and the chorion does not present differentiation of layers. The follicular epithelium alters its shape according to the development phase of the oocyte. Part of the vitellus is from exogenous origin and part is endogenous. Before this, only two studies about the ultrastructural analysis of the female germ cells of diplopods were published. Microsc. Res. Tech. © 2012 Wiley Periodicals, Inc.
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  • 19
    Publikationsdatum: 2012-10-17
    Beschreibung: The method to observe the exact morphology of swelled seaweed as an example of biological material by field emission scanning electron microscopy (FE-SEM) with the aid of hydrophilic ionic liquid (IL); 1-butyl-3-methylimidazolium tetrafluoroborate is reported. Seaweed was first swelled in 3.5% NaCl solution and then treated with the IL and water mixture in 1:7 weight ratios and centrifuged to remove the excess IL solution. Thus treated seaweed maintained its morphology even at high magnification and did not show drying in the FE-SEM chamber. This observation technique might be useful for various kinds of biological materials to be observed under FE-SEM. Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc.
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  • 20
    Publikationsdatum: 2012-10-18
    Beschreibung: Purpose: The aim of this in vitro study was to verify the interference of previous application of sodium hypochlorite in the bond strength to dentin irradiated with Er:YAG laser (80 mJ, 2 Hz, 25 J/cm 2 ), using two adhesive systems with different solvents (Adper Single Bond2 – 3M ESPE [SB] and Prime&Bond 2.1 – Dentsply [PB]. Study Design: Ninety standardized dentin disks were treatment with phosphoric acid etching (PA), PA and 10% sodium hypochlorite (SH), Er:YAG laser (ER), ER and 10% SH. After surface preparation, samples received SB or PB followed by composite resin Z250 (3M ESPE)( n = 10). Tensile bond strength test was performed (0.5 mm/min) 24 h after bonding procedure and one treated dentin disk of each group was selected to scanning and transmission electron microscopy (SEM and TEM) observations. Bond strength test data were evaluated by three-way ANOVA and Tukey ( P 〈 0.05) tests. Results: Tested systems had similar bonding behavior when applied with conventional method. SH produced no improvement in bond strength. Phosphoric acid etching either associated with SH, or not, provided higher bond strength values than ER. SEM showed typical ablation pattern on dentin after ER irradiation. SH application after PA promoted greater porosity in intertubular dentin exposing secondary tubules. SH used after ER irradiation showed more evident peritubular dentin. TEM results showed that both PA and ER exposed inter- and peri-tubular dentin collagen fibers. Conclusions: Er:YAG irradiation had a negative influence on SB adhesive, and in both methods, association of SH did not completely remove collagen fiber network, but altered its configuration. Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc.
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  • 21
    Publikationsdatum: 2012-10-18
    Beschreibung: Environmental factors can influence the reproductive rates in bats, and since morphometric information of bats testis is scarce, we aimed to compare the organization and quantification of the intertubular components in the testes of the bat Molossus molossus , collected in different seasons. Testicular histological sections were evaluated using light and electron microscopy. The intertubular compartment occupied an average 10% of the testes, being predominately constituted of Leydig cells (LC). The percentages of the testes occupied by the intertubular compartment and by LC were significantly higher in summer, while the other intertubular components did not vary significantly among the seasons. As suspected under light microscopy, the ultrastructural analysis confirmed the existence of multinucleated LC during winter. The increase in the nuclear percentage of LC in winter seems to have caused the decrease of the cytoplasmatic measurements in that season, as well as in the volume of LC. The highest cytoplasmatic values and volume of LC registered in the spring, summer, and fall can be related to greater activity of this cell in these seasons. The higher investment in intertubular tissue and in LC observed in summer, compared to winter; suggest an increase in the steroidogenic capacity of this bat during summer. The analyses correlating testicular morphometry and abiotic environmental factors in this study confirm the influence of climatic factors on the reproduction of M. molossus . Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc.
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  • 22
    Publikationsdatum: 2012-10-18
    Beschreibung: Insects rely heavily on olfaction to locate habitat, mates, and oviposition sites, while odorant molecules and the antennal olfactory sensory cells of insects are two indispensable components of olfactory response. Our previous work identified the sex pheromones and volatile compounds derived from host plant of Dendrolimus tabulaeformis Tsai et Liu, a serious economic pest of pines in northern China. However, little is known about the olfactory system of D. tabulaeformis , especially in females. To make a better understanding of the D. tabulaeformis olfactory response, we investigated the structure, innervation, numbers, and distribution of sensilla on the antennae of male and female moth, based on scanning and transmission electron microscopy. The pinniform antennae of this moth bear five types of sensilla: trichoid (TS), basiconica (BS), styloconic (StS), and chaetica (ChS) sensilla, and belt-type structures (BTSs). The BTSs are hollow and are not chemical sensilla. The ChSs occur on the scape. StS contain dendrite sheaths and four dendrites containing microtubules in their cores. The BS contents are continuous with that in the subsegments. The TSs were sexually dimorphic and could be divided into 12 subtypes based on dendrite number and form. TS1-4 contained two, three, or four dendrites and were similar in both sexes. TS 5-8 and TS 9-12 occurred only on male and female antenna, respectively. We discussed the possible functions of these sensilla. Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc.
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  • 23
    Publikationsdatum: 2012-10-18
    Beschreibung: PURPOSE: To investigate the changes in the ultrastructural architecture of hydrated corneoscleral button (HCSB) and hydrated corneal button (HCB). METHOD: Corneoscleral buttons ( n = 4) and corneal buttons ( n = 4) were hydrated in deionized water for 24 and 48 h and were fixed in 2.5% glutaraldehyde containing cuprolinic blue in sodium acetate buffer and processed for electron microscopy. The tissue was dehydrated and embedded in TAAB 031 resin. Normal CSB and CB were also processed using the same method. Ultrathin sections were stained with uranyl acetate and lead citrate. The sections were observed under JEOL 1400 transmission electron microscope. RESULTS: In both HCSB and HCB, the lamellae were disorganized and proteoglycans (PGs) were degenerated and detached from the collagen fibrils (CFs). In the HCSB samples, interfibrillar spacing increased but the diameter of the CF had not changed compared with those in the normal tissue. Within the HCSB, the interfibrillar spacing in the posterior stroma was significantly higher compared with those in the anterior and middle stroma. In the HCB, both the interfibrillar spacing and CF diameter had significantly increased compared to those observed in both the HCSB and normal tissue. The CFs were severely damaged exhibiting very thin microfilaments within CFs. Remnants of the CFs were present in the stromal matrix. CONCLUSION: Hydration of the cornea in both the HCSB and HCB increases the interfibrillar spacing in the anterior, middle, and posterior stroma. The CF in the HCB was enlarged and had degenerated. This could be due to penetration of water into the intermolecular spacing within the CF. Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc.
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  • 24
    Publikationsdatum: 2012-04-15
    Beschreibung: This research aimed to examine the morphological features of the tongue and laryngeal entrance of long-legged buzzard by macroscopic and scanning electron microscopic methods. Two adult buzzards were used as material. The tongue was fairly elongated and terminated in oval shovel-like apex. Scale-like projections were localized on the apex and body of tongue. Both lateral sides of lingual body were contained considerably long thread-like projections. Many orifices of lingual posterior salivary glands were discerned among scale-like projections in median sulcus of the lingual body. Papillary crest of sharp conical papilla were observed on the between the body and root of the tongue. No conical papillae or other projections were existent on the root of the tongue, but numerous orifices of posterior salivary gland ducts were detected. In addition, orifices of anterior salivary gland ducts were present on the dorsal and lateral surfaces of the lingual body. Numerous conical papillae were observed on the caudal region of glottis and no conical papillae or any similar projection which were bordered the glottic fissure was noted. Anatomy of these organs in the long-legged buzzard and white tailed eagle which are the member of the same family, Accipitridae, revealed very high similarity. Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc.
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  • 25
    Publikationsdatum: 2012-04-15
    Beschreibung: This study aimed to evaluate the effect of four chemomechanical surface treatments on the surface average microroughness and profile of laser-sintered and vacuum-cast dental prosthetic structures. Square-shaped blocks (10 mm × 10 mm × 1.5 mm) were prepared as follows: (1) laser-sintered Co Cr (L) (ST2724G); (2) cast Co Cr (C) (Gemium-cn); and (3) cast Ni Cr Ti (T) (Tilite). Specimens of each alloy group were randomly divided into five subgroups ( n = 10 each), depending on the conditioning method used: (1) no treatment (control); (2) sandblasting (125 μm Al 2 O 3 -particles); (3) silica coating (50 μm silica-modified Al 2 O 3 -particles); (4) oxidation; and (5) oxidation plus opacification. Subgroups 2 and 3 represent “inner” pretreatments proposed for ceramometal restorations to improve the metal surface area available for luting cements. Subgroups 4 and 5 are the “outer” pretreatments required for bonding the aesthetic veneering ceramics to the underlying metal frameworks. Average surface roughness (Ra/μm) was determined using a surface profilometer. Data were analyzed by two-way ANOVA and Student–Newman–Keuls tests (α = 0.05). Metal surface topography was SEM-analyzed. Despite the inner pretreatment applied, L samples resulted in the highest microroughness ( P 〈 0.001), whereas sandblasting produced a surface-smoothing effect in cast specimens. After oxidation, a significant increase in surface roughness occurred in all groups compared with controls, L specimens being the roughest ( P 〈 0.001). Opacification caused a flattening effect of all oxidized structures; all opacified groups resulting in similar microroughness. Laser sintering of Co Cr enhances the roughness of metal structures, which may improve the frameworks' microretention of the cements, and of the opaquer before the copings are veneered with the aesthetic ceramics. Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc.
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  • 26
    Publikationsdatum: 2012-04-15
    Beschreibung: There is an increasing variety of endocrine disrupting chemicals (EDCs) either with (anti)estrogenic or (anti)androgenic potential widely present in the environment. These xenosteroids may mimic endogenous steroid hormones disrupting the homeostasis of physiological pathways and leading to several disturbances, especially in tissues highly dependent on steroid hormones such as the prostate. Taking this into account, this comparative study aimed to verify the potential of ethinylestradiol (EE) and testosterone acting as ECDs on the prostate of both male and female adult gerbils exposed to these agents during the embryonic phase. Consequently, pregnant gerbils were treated either with 10 μg/kg/day of EE or with a single dose of 1 mg of testosterone cypionate. The pups that were born 6–8 days after testosterone exposure and the pups that were born after 3 days of EE exposure were allowed to grow but were sacrificed within 4 months. Serological, morphological, stereological, and immunohistochemical analyses were used. Overall, the results showed that both sexes exposed to testosterone and EE during gestation had a prostatic gland with an increased stromal and epithelial and a reduced luminal compartment. Moreover, we observed that glands affected with prostatic intraepithelial neoplasia showed intense stromal reshuffling. In conclusion, although these alterations were observed in both sexes, more relevant to this study was the differential responsiveness of males and females exposed to these different drugs. Whereas the EE affected males more, the testosterone was more harmful to the females. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.
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  • 27
    Publikationsdatum: 2012-04-15
    Beschreibung: Electron microscopy has been used to visualize chromosome since it has high resolution and magnification. However, biological samples need to be dehydrated and coated with metal or carbon before observation. Ionic liquid is a class of ionic solvent that possesses advantageous properties of current interest in a variety of interdisciplinary areas of science. By using ionic liquid, biological samples need not be dehydrated or metal-coated, because ionic liquid behaves as the electronically conducting material for electron microscopy. The authors have investigated chromosome using ionic liquid in conjunction with electron microscopy and evaluated the factors that affect chromosome visualization. Experimental conditions used in the previous studies were further optimized. As a result, prewarmed, well-mixed, and low concentration (0.5∼1.0%) ionic liquid provides well-contrasted images, especially when the more hydrophilic and the higher purity ionic liquid is used. Image contrast and resolution are enhanced by the combination of ionic liquid and platinum blue staining, the use of an indium tin oxide membrane, osmium tetroxide-coated coverslip, or aluminum foil as substrate, and the adjustment of electron acceleration voltage. The authors conclude that the ionic-liquid method is useful for the visualization of chromosome by scanning electron microscopy without dehydration or metal coating. Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc.
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  • 28
    Publikationsdatum: 2012-04-15
    Beschreibung: The glycoconjugate pattern of developing ovarian follicles in wild and cultured Senegalese sole Solea senegalensis was investigated by means of lectin histochemistry. Ovaries from cultured fish contained oocytes up to the late vitellogenic stage, whereas they reached the hydration stage in wild specimens. The follicular cells bound MAL II, SBA, HPA, DBA, Con A, KOH-sialidase (K-s)-WGA, GSA I-B 4 in the late vitellogenic stage, and in wild fish also SNA and K-s-PNA, whereas in the hydration stage SBA, HPA, DBA, and GSA I-B 4 only. The zona radiata reacted with SBA, HPA, DBA, Con A, and GSA I B 4 in the late vitellogenic stage and in cultured fish also with UEA I, whereas in the hydration stage it stained with SBA only. The cortical alveoli bound SBA, HPA, RCA 120 during the late vitellogenic stage, also SNA, PNA, K-s-PNA, GSA I-B 4 in cultured fish, DBA, and K-s-WGA in wild ones which stained with SBA, HPA, and GSA I-B 4 in the hydrated stage. The yolk reacted with Con A in the late vitellogenic oocytes, and also with MAL II, SNA, K-s-PNA, SBA, HPA, K-s-WGA, GSA I-B 4 , UEA I in the hydrated ones. From perinucleolus to late vitellogenic stages, the oocyte nucleoplasm bound Con A, GSA I-B 4 , GSA II, UEA I, and in wild fish also MAL II, SNA, LTA but only GSA I-B 4 reactivity in the early maturation stage. These findings demonstrate that the glycan pattern of fish ovarian follicles changes during the maturative stages and that it is affected by culture-rearing conditions. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.
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  • 29
    Publikationsdatum: 2012-04-15
    Beschreibung: Leafcutter ants of the genus Atta Fabricius are serious agricultural pests. Morphological studies of immature stages within this group are few, and the data provided for species of considerable importance are usually incomplete. In this study, the immatures of Atta sexdens Linnaeus are described and compared using light and scanning electron microscopy. Only specimens from founding stage colonies (i.e., lacking adult workers) were used. The existence of four larval instars was estimated by a frequency plot of maximum head widths, and the larvae of different instars differed from each other mainly by their bodily dimensions. Worker larvae belonged to two distinct morphological castes: (1) gardeners and nurses and (2) within-nest generalists. The worker larvae described in this study differed from a previous description of the same species by the following traits: the existence of a genal lobe, the number of clypeal hairs, the presence of two hairs on the ninth abdominal somite, the presence of hairs on the anterior surface of the labrum, and the shape of the maxillary palpus. This study provides a comparative analysis of immature stages of A. sexdens that may be relevant to future morphological and biological studies of the Attini. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.
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  • 30
    Publikationsdatum: 2012-04-15
    Beschreibung: Here we report a new sample preparation method for three-dimensional electron tomography. The method uses the standard film deposition and focused ion beam (FIB) methods to significantly reduce the problems arising from the projected sample thickness at high tilt angles. The method can be used to prepare tomography samples that can be imaged up to a ±75° tilt range which is sufficient for many practical applications. The method can minimize the problem of Ga + contamination, as compared to the case of FIB preparation of rod-shaped samples, and provides extended thin regions for standard 2D projection analyses. Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc.
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  • 31
    Publikationsdatum: 2012-04-15
    Beschreibung: The liver has a remarkable ability to regenerate after partial hepatectomy (PH), although the factors governing such ability are still poorly understood. During the prereplicative phase of the regeneration, ultrastructural alterations of periportal hepatocytes were seen, including mitochondrial swelling, abnormal accumulation of lipids, and myelin figures which could lead to the formation of lipid droplets. As it has been hypothesized that caveolin-1 is involved in lipidogenesis and in mitochondrial homeostasis, we aimed to study the subcellular distribution of caveolin-1 in hepatocytes at an early stage following PH. Liver samples were processed for light and electron microscopy at 0 h, 24 h, and 96 h after PH. The expression and subcellular distribution of caveolin-1 was assessed by immunohistochemical and immunocytochemical techniques. Following PH, at 24 h, membranes of altered mitochondria of periportal hepatocytes exhibited significant decrease of caveolin-1 expression compared with control. Myelin figures showing high expression of caveolin-1 were also seen. At 96 h, hepatocytes became ultrastructurally similar to the control liver, and the expression of caveolin-1 on mitochondria showed a moderate increase compared with 24 h after PH. Decrease of expression of caveolin-1 in the altered liver mitochondrial membranes at 24 h following PH, and the high expression of caveolin-1 observed on myelin figures, suggests involvement of caveolin-1 is in both mitochondrial homeostasis and lipidogenesis. Addressing the role played by caveolin-1 during liver regeneration might disclose additional features of mitochondrial homeostasis and lipidogenesis during frequent metabolic liver diseases. Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc.
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  • 32
    Publikationsdatum: 2012-04-15
    Beschreibung: The pumping organ of blood-sucking female mosquitoes has a three-dimensional (3D) structure. However, conventional two-dimensional imaging methods are insufficient for visualizing the 3D structure in detail. Furthermore, their 3D imaging tasks are highly time consuming and sample preparation process requires elaborate skill. Among 3D imaging techniques, synchrotron X-ray microscopic computed tomography (SR-μCT) is especially suitable for small insects with opaque cuticles, such as mosquitoes. In this study, the 3D morphological structure of the pump system of a female mosquito was visualized using SR-μCT. Expandable volume capacities of two pump chambers were measured for several mosquito samples of similar size. To verify the cross-sectional images acquired by SR-μCT, complementary paraffin-sectioning data were compared. Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc.
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  • 33
    Publikationsdatum: 2012-04-15
    Beschreibung: The aim of this study was to evaluate the persistence of resin cement residues after dentin surface cleaning with different alcohol-based solutions or an essential oil (eucalyptol). Forty bovine teeth were sectioned in order to expose pulp chamber dentin to be washed with 1.0 mL of 2.5% sodium hypochlorite (NaOCl), followed by 0.1 mL of 17% EDTA application for 3 min, and final irrigation with 2.5% NaOCl. The specimens were air dried and resin-based cement was rubbed onto the dentine surface with a microbrush applicator. After 15 min, the surface was scrubbed with a cotton pellet and moistened with different dentin cleaning solutions, compounding the following groups: G1—95% ethanol, G2—70% ethanol, G3—70% isopropyl alcohol, or G4—eucalyptol. The dentin was scrubbed until the cement residues could not be visually detected. Sections were then processed for SEM and evaluated at ×500 magnification. Scores were attributed to each image according to the area covered by residual sealer, and data were subjected to Kruskal–Wallis at 5% significance. Eucalyptol promoted the most adequate dentin cleaning, although no statistical difference was detected amongst the groups ( P 〉 0.05), except between the eucalyptol and 70% ethanol groups ( P 〈 0.05). All the evaluated dentin cleaning solutions were unable to completely remove the cement residues from the dentin surface. Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc.
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  • 34
    Publikationsdatum: 2012-04-15
    Beschreibung: Apatura ilia (Denis and Schiffermüller, 1775) and A. iris (Linnaeus, 1758) are fascinating butterflies found in the Palaearctic ecozone (excepting the north of Africa). The wings of these insects are covered with a great number of two types of scales positioned like roof tiles. Type I scales are on the surface, while type II scales are situated below them. The structural color of the type I scales is recognized only on the dorsal side of both the fore and hind wings of the males of the aforementioned species. Both types of scales are responsible for pigment color of the wings, but iridescence is observed only in the type I scales. The brilliant structural color is due to a multilayer structure. The features of the scales, their dimensions and fine structure were obtained using scanning electron microscopy. Cross sections of the scales were then analyzed by transmission electron microscopy. The scales of the “normal” and clytie forms of A. ilia have a different nanostructure, but are of the same type. A similar type of structure, but with a different morphology, was also noticed in A. iris . The scales of the analyzed species resemble the scales of tropical Morpho butterflies. Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc.
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  • 35
    Publikationsdatum: 2012-04-15
    Beschreibung: Titanium surface texture and chemistry modification successfully improves the host response and consequently the bone-to-implant contact surrounding dental implants. The aim of the present study was to investigate, using histomorphometrical-analysis, the effects of titanium surface modification by laser-ablation (Nd:YAG) followed by thin chemical deposition of HA. Forty-eight rabbits received one implant by tibiae of AS-machined (MS), laser-modified (LMS), or biomimetic hydroxyapatite-coated (HA) surface. Bone-to-implant contact (BIC) and bone area (BBT) were evaluated after 4, 8, and 12 weeks, at cortical and cancellous regions. Average BIC in the cortical region was higher ( P 〈 0.001) on the LMS and HA implants for all periods, with no differences between LMS and HA. For the cancellous area, the LMS and HA implants showed higher ( P 〈 0.01) BIC than MS at the initial periods. The LMS and HA showed similar values in the cortical region, but a tendency of higher values for HA in the cancellous region was observed in all periods. For the BBT, the differences were found only between HA and MS after 4 weeks in the cortical region ( P 〈 0.05), and after 12 weeks in the cancellous area ( P 〈 0.05). Our results showed that HA biomimetic coating preceded by laser treatment induced the contact osteogenesis and allowed the formation of a more stable bone–implant interface, even in earlier periods. Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc.
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  • 36
    Publikationsdatum: 2012-04-15
    Beschreibung: Chrysomya megacephala is a forensic important fly, and its immature forms also cause myiasis. The adults are the first insects to reach a carcass and can oviposit just a few hours after arrival. Therefore, the knowledge of immature stages of flies is essential for correct identification of the species found on corpses. Scanning electron microscopy (SEM) gives detailed information on the morphological characters that can help identify the immature forms of flies. The aim of this study is to identify larvae and puparia of C. megacephala using SEM. The larval instar body of C. megacephala is similar at all instars. The integument is smooth with small spines located at the limit of all segments. The cephalic region has a group of robust spines with one or two tips. The puparia are very similar to third instar larvae, except for the cephalic structures that are retracted. The integument shows the wrinkles from the third instar larvae and posterior spiracle disc with three spiracular openings localized on the top of an elevation. In conclusion, SEM provides some characteristics to distinguish among Chrysomya species that could help entomologists to identify immature found on corpses. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.
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  • 37
    Publikationsdatum: 2012-04-15
    Beschreibung: Egg morphology of nine species of the cluster fly genus Pollenia Robineau-Desvoidy was studied with scanning electron microscopy. Funnel-shaped micropylar area, chorion covered with centrally depressed hexagons, well developed hatching pleats on the dorsal surface encompassing the median area were found in eggs of all species: P. amentaria (Scopoli), P. angustigena Wainwright, P. atramentaria (Meigen), P. labialis Robineau-Desvoidy, P. mayeri Jacentkovsky, P. pediculata Macquart, P. rudis (Fabricius), P. similis (Jacentkovsky), and P. vagabunda (Meigen). Untypical for Calliphoridae, a dual morphological structure of plastron-bearing area is described here for the first time. On the basis of our observations, all species studied share the presence of a plastron respiratory function on the entire surface between the hatching lines. Differences between species were found in the shape of the longitudinal hatching pleats and the proportion between ‘island pattern’ and ‘hexagonal pattern’ of their chorionic surface, and in the intensity of perforation of hexagons of the median area. Comparisons of Pollenia egg morphology with that of other representatives of Calliphoridae revealed its unique structure, allowing easy differentiation from other representatives of the family. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.
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  • 38
    Publikationsdatum: 2012-04-15
    Beschreibung: A reliable procedure for measuring parameters connected to surface roughness is needed to compare the gas sensing properties of various thin films or the effect of different fabrication procedures on the surface roughness and the sensing properties. In this article, we propose to investigate how the acquisition parameters specific to atomic force microscopy investigations such as pixel size, scan area and scan speed influence the roughness parameters, namely root mean square and surface area ratio, commonly used for characterizing the gas sensing properties of porphyrins and other materials. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.
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  • 39
    Publikationsdatum: 2012-04-15
    Beschreibung: OBJECTIVES: The aim of this in vitro study was to investigate the efficacy of in-office bleaching technique combined with the application of a casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) paste (MI Paste–MI) at different moments and its influence on enamel surface properties. METHODS: Eighty bovine dental crowns were randomly allocated into eight groups ( n = 10), and bleached with either 35% hydrogen peroxide (HP) or 37% carbamide peroxide (CP). Four different protocols of application of MI were considered: without MI, MI applied before bleaching, MI applied after bleaching, and MI applied both before and after bleaching. Bleaching effectiveness was measured by the VITA EasyShade spectrophotometer utilizing the CIEL*a*b* system (Δ E , Δ L *, Δ a *, and Δ b *). Color readings were measured at baseline, 7, 14, and 21 days. Hardness and roughness were measured at baseline (T0) and immediately after bleaching (T14). Data were subjected to the two-way ANOVA for repeated measurements and Tukey's test at 5%. RESULTS: HP groups achieved the greatest color change. The application of a CPP-ACP paste did not reduce the efficacy of bleaching peroxides. Samples bleached with CP showed decreased hardness at T14. Samples bleached with HP that received the application of MI before and before/after bleaching did not present hardness decrease at T14. Samples bleached with peroxides only and received MI after bleaching showed increased roughness at T14. CONCLUSIONS: The use of CPP-ACP was able to prevent negative changes in roughness and hardness of bovine enamel when associated to hydrogen peroxide, and might be applied before/after the bleaching protocol. Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc.
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  • 40
    Publikationsdatum: 2012-04-15
    Beschreibung: Background : Diabetes mellitus results in many complications, also compromising the salivary glands. The current treatment for this condition should be a substituting method to exogenous insulin. In this aspect, the immunotherapy has been tested, but, it can be inefficient as an agent for the control of damage caused by diabetes. Thus, the aim of this study was to evaluate the anti-CD3 monoclonal antibody as alternative immunotherapy in the recovery of salivary glands of spontaneously diabetic NOD (nonobese diabetic) mice. Methods : NOD mice were divided into two groups of 10 animals: group I (untreated diabetic mice) and group II (anti-CD3-treated diabetic mice). After treatment, the samples of salivary glands were collected for histological examination under both transmitted and polarized light microscopy. Results : Alterations in tissue architecture; increase in extracellular matrix and presence of inflammatory process were observed in untreated animals. Recovery of the salivary acinar cells occurred in treated animals. The parotid glands demonstrated a smaller amount of collagen fibers and were not observed severe inflammatory processes. Conclusion : These results indicate that immunotherapy contributed to reestablishment of tissue damaged by the hyperglycemic condition, demonstrating that the immunomodulation plays an important role in the recovery of salivary glands. Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc.
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  • 41
    Publikationsdatum: 2012-04-15
    Beschreibung: Despite the large number of species, their wide distribution, and unique reproductive characteristics, Neotropical bats have been poorly studied, and important aspects of the reproduction of these animals have not been elucidated. We made an ultrastructural analysis of spermatogenesis in Molossus molossus (Molossidae). The process of spermatogonial differentiation is similar to that found in other bats and is also relatively similar to that of Primates, with three main spermatogonia types: A d , A p , and B. Meiotic divisions proceed similarly to those of most mammals, and spermiogenesis is clearly divided into 12 steps, in the middle of the range known for bats (9–16 steps). Formation of the acrosome is similar to that known from other mammals; however, the ultrastructure of spermatozoa was found to have unique characteristics, including many wavy acrosomal projections on its surface, which seems to be specific for the family Molossidae. Comparing the ultrastructure of the spermatozoon of M. molossus with other bats already study, we observed that three characters vary: morphology of the outer dense fibers, of the perforatorium, and of the spermatozoon head. The great similarity of morphological characters between M. molossus and Platyrrhinus lineatus suggests that M. molossus is more closely related to the Phyllostomidae than to the Rhinolophidae and the Vespertilionidae. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.
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  • 42
    Publikationsdatum: 2012-04-15
    Beschreibung: Although the Geographical Information System (GIS), which integrates computerized drawing computer assisted design (CAD) and relational databases (data base management system (DBMS)), is best known for applications in geographical and planning cartography, it can also use many kinds of information concerning the territory. A multidisciplinary project was initiated since 5 years a multidisciplinary study was initiated to use GIS to integrate environmental and ecological data with findings on animal health, ethology, and anatomy. This study is chiefly aimed at comparing two different methods for measuring the absorptive surface of rumen papillae. To this scope, 21 female sheep ( Ovis aries ) on different alimentary regimes (e.g., milk and forage mixed diet, early herbaceous diet, dry hay diet, and fresh hay diet at the maximum of pasture flowering and at the maximum of pasture dryness) were used; after slaughtering, 20 papillae were randomly removed from each sample collected from four indicator regions of rumen wall, placed near a metric reference and digitally photographed. The images were developed with the ArcGIS™ software to calculate the area of rumen papillae by means of GIS and to measure their mid-level width and length to calculate the papillae area as previously performed with a different method. Spatial measurements were analyzed using univariate and multivariate methods. This work demonstrates that the GIS methodology can be efficiently used for measuring the absorptive surface of rumen papillae. In addition, GIS demonstrated to be a rapid, precise, and objective tool when compared with previously used method. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.
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  • 43
    Publikationsdatum: 2012-04-15
    Beschreibung: To help understand the mechanism of host discrimination during oviposition of a parasitoid wasp, Venturia canescens (Gravenhorst) (Hymenoptera: Ichneumonidae), the ultrastructure and morphology of the sense organs on the dorsal and ventral stylets of the ovipositor were examined using scanning and transmission electron microscopy. Ovipositor stylets were scanned for sense organs, because only unsheathed ovipositors are used for probing, stabbing, and host discrimination. Five types of sensilla and secretary pores were identified. Based on their pattern of innervation, the surface-dome and pitted-dome sensilla were thought to have a gustatory function and, thus, are the best candidates for host-discrimination. The arrangements of dendrites of type I and type II campaniform sensilla suggested that these acted as pressure- and mechano-receptors, respectively. Coeloconic sensilla might act as thermo-hygroreceptors, whilst secretary pores might provide lubrication during the process of stabbing for oviposition. Surface-dome sensilla were the most numerous type found followed by secretary pores, pitted-dome sensilla, and coeloconic sensilla. Almost all the sensilla and secretary pores were more numerous on the dorsal than on the ventral stylets, and the maximum number of these sensilla and secretary pores occurred on the distal end of the ovipositor stylets and decreased toward the proximal end. The surface-dome sensilla and secretary pores occurred in alternate rows while the pitted-dome sensilla were scattered all over the surface of the ovipositor stylets, especially on the sides of the stylets. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.
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  • 44
    Publikationsdatum: 2012-04-15
    Beschreibung: The speed and accuracy of Förster resonance energy transfer (FRET) measurements can be improved by rapidly alternating excitation wavelengths between the donor and acceptor fluorophore. We demonstrate FRET efficiency measurements based on a fiber laser and photonic crystal fiber as the source for two-photon excitation (TPE). This system offers the potential for rapid wavelength switching with the benefits of axial optical sectioning and improved penetration depth provided by TPE. Correction of FRET signals for cross excitation and cross emission was achieved by switching the excitation wavelength with an electrically controlled modulator. Measurement speed was primarily limited by integration times required to measure fluorescence. Using this system, we measured the FRET efficiency of calmodulin labeled with Alexa Fluor 488 and Texas Red dyes. In addition, we measured two-photon induced FRET in an E 0 GFP-mCherry protein construct. Results from one-photon and two-photon excitation are compared to validate the rapid wavelength switched two-photon measurements. Microsc. Res. Tech., 2011. © 2011 Wiley Periodicals, Inc.
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  • 45
    Publikationsdatum: 2012-04-15
    Beschreibung: The purpose of this study was to compare the inorganic content and morphology of one nanofilled and one nanohybrid composite with one universal microhybrid composite. The Vickers hardness, degree of conversion and scanning electron microscope of the materials light-cured using LED unit were also investigated. One nanofilled (Filtek™ Supreme XT), one nanohybrid (TPH® 3 ) and one universal microhybrid (Filtek™ Z-250) composite resins at color A 2 were used in this study. The samples were made in a metallic mould (4 mm in diameter and 2 mm in thickness). Their filler weight content was measured by thermogravimetric analysis (TG). The morphology of the filler particles was determined using scanning electron microscope equipped with a field emission gun (SEM-FEG). Vickers hardness and degree of conversion using FT-IR spectroscopy were measured. Filtek™ Z-250 (microhybrid) composite resin shows higher degree of conversion and hardness than those of Filtek™ Supreme XT (nanofilled) and TPH® 3 (nanohybrid) composites, respectively. The TPH 3 ® (nanohybrid) composite exhibits by far the lowest mechanical property. Nanofilled composite resins show mechanical properties at least as good as those of universal hybrids and could thus be used for the same clinical indications as well as for anterior restorations due to their high aesthetic properties. Microsc. Res. Tech., 2011. © 2011 Wiley Periodicals, Inc
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  • 46
    Publikationsdatum: 2012-04-15
    Beschreibung: OBJECTIVE: Signal pattern enumeration of Urovysion Fluorescence in Situ Hybridization test is tedious and requires great experience. Our aim was to eliminate human interaction by automating the process, using an adoptable, automated image acquisition, and analysis system. METHODS: For extensive analytical analysis control, cell populations were used, while preliminary clinical study was performed on 21 patients with clinical suspicion for bladder cancer. All investigations were carried out using an automated user-trainable workstation (Metafer4-Metacyte). RESULTS: The system identified nuclei with a specificity and sensitivity of 92.7 and 96.6%, respectively, while signal detection accuracy was 81.1% on average. Both analytical and diagnostic accuracy of automated analysis was comparable to manual approach (94.8 and 71% vs. 97.9 and 76%, respectively), but classification accuracy increased with degree of polysomy, thus diagnostic sensitivity in low grade, low stage cases was poor. CONCLUSION: It is possible to automate signal enumeration of Urovysion using a user-trainable system, and achieve efficiency comparable to manual analysis. Previously introduced automated immunophenotypic targeting should further increase diagnostic sensitivity, while resulting in a comprehensively automated method. However, the problem of reduced detection accuracy in cases featured with low polysomy is likely to remain a great challenge of automated signal enumeration. Microsc. Res. Tech. 2011. © 2011 Wiley Periodicals, Inc.
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  • 47
    Publikationsdatum: 2012-04-11
    Beschreibung: This study aimed to evaluate the effect of four chemomechanical surface treatments on the surface average microroughness and profile of laser-sintered and vacuum-cast dental prosthetic structures. Square-shaped blocks (10 mm × 10 mm × 1.5 mm) were prepared as follows: (1) laser-sintered Co Cr (L) (ST2724G); (2) cast Co Cr (C) (Gemium-cn); and (3) cast Ni Cr Ti (T) (Tilite). Specimens of each alloy group were randomly divided into five subgroups ( n = 10 each), depending on the conditioning method used: (1) no treatment (control); (2) sandblasting (125 μm Al 2 O 3 -particles); (3) silica coating (50 μm silica-modified Al 2 O 3 -particles); (4) oxidation; and (5) oxidation plus opacification. Subgroups 2 and 3 represent “inner” pretreatments proposed for ceramometal restorations to improve the metal surface area available for luting cements. Subgroups 4 and 5 are the “outer” pretreatments required for bonding the aesthetic veneering ceramics to the underlying metal frameworks. Average surface roughness (Ra/μm) was determined using a surface profilometer. Data were analyzed by two-way ANOVA and Student–Newman–Keuls tests (α = 0.05). Metal surface topography was SEM-analyzed. Despite the inner pretreatment applied, L samples resulted in the highest microroughness ( P 〈 0.001), whereas sandblasting produced a surface-smoothing effect in cast specimens. After oxidation, a significant increase in surface roughness occurred in all groups compared with controls, L specimens being the roughest ( P 〈 0.001). Opacification caused a flattening effect of all oxidized structures; all opacified groups resulting in similar microroughness. Laser sintering of Co Cr enhances the roughness of metal structures, which may improve the frameworks' microretention of the cements, and of the opaquer before the copings are veneered with the aesthetic ceramics. Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc.
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  • 48
    Publikationsdatum: 2012-04-11
    Beschreibung: We have conducted a morphological study of the ampullae of Lorenzini on two shark species from Squatina Genus. In both species, S. guggenheim and S. occulta , the ampullae were observed like small pores scattered in the head region similar to other species of the Chondrichthyes Class. However, differently of the other species a greatest density of ampullae of Lorenzini was observed along of the body surface. After fixation using 10% formaldehyde, the ampullae were removed and processed for light and scanning electron microscopy. Macroscopically, the two shark species differed by the presence of dorsal spines that appeared from the head to the first dorsal fin in S. guggenheim and were absent in S. occulta . Microscopically, there were no differences between the ampullae of Lorenzini channels in these two species. The wall of the ampulla was formed by a simple squamous epithelium. Bands of connective tissue, hyaline cartilage and collagen fibers were found between the ampulla and the skeletal striated muscle layer. Nerve branches responsible for conducting signal pulses to the central nervous system were visible between the muscle and connective tissue layers. Using scanning electron microscopy and histological analysis, we found that the channels were twisted and positioned parallel to the skin. The inside of the channels contained a large amount of a gelatinous secretion composed by polysaccharides. Therefore, we conclude that the morphological combination of extended distribution of the ampullae of Lorenzini and the body shape may represent an adaptation of these species to their way of life. Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc.
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  • 49
    Publikationsdatum: 2012-04-11
    Beschreibung: The low-shrink Silorane-based composite could bond effectively to bone and showed the potential be used as a bone cement. Bone organ culture maintains the anatomical order, natural cell-to-cell and cell-to-matrix relationship. The purpose of this study was to evaluate the responses of bone cells to a Silorane-based composite which was compared with a representative polymethyl methacrylate (PMMA) bone cement. The critical size defects were created through the parietal bones from one litter of mice. The paired bones were divided into two groups: Silorane-based composite group and PMMA group. The prepared two groups of disks were put into the defects. The cultures were grown in vitro for 38 days and analyzed with microcomputed-tomography, dissecting-microscope, phase- contrast-microscope, scanning-electron-microscopy, and energy- dispersive-X-ray. At the 10th day, the Silorane disk was almost fully covered by a sheet of cells but the cells hardly attached to the disk surface. The edge of the PMMA disk was covered by a sheet of cells and the migrated individual cells attached to the whole surface of the disk. At the 38th day, some cells attached to the exposed disk area of the Silorane disk while the formed tissues covered the whole surface of the PMMA disk. The collagen fibers, globular deposits and bone formation were visible in both groups. The Silorane-based composite showed promise as a potential bone cement when compared with PMMA which is used in clinical orthopedics. However, the cell attachment to PMMA was evidently better than to Silorane-based composite. Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc.
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  • 50
    Publikationsdatum: 2012-04-07
    Beschreibung: Stroke is associated with the intracerebral formation of fibrin clots which may lead to irreversible brain damage. Thrombolytic therapies employ a variety of natural and/or recombinant plasminogen activators to initiate fibrinolytic degradation of cerebral thrombi. However, such therapies when installed beyond 4- to 6-h window, may fail to achieve the expected outcome. This is due to the hydroxyl radical-induced modification of fibrin(ogen) molecules rendering them refractory to fibrinolytic degradation, but no cause of the increased free radical generation in stroke was offered. Here, we show by means of electron microscopy that iron ions added to human blood dramatically enhances fibrin fibers formation with thrombin, and significantly delays fibrinolysis during spontaneous clotting of native blood. Iron ions caused the appearance dense matted fibrin deposits, similar, if not identical, to those observed in plasma of patients with stroke. These results may explain a known relationship between thrombotic diseases and the increased body concentrations of free iron and/or hemoglobin derivatives. We conclude that any action resulting in the inhibition of hemostatic abnormalities, as well as in the reduction of body free iron and scavenging of hydroxyl radicals (e.g., by polyphenols) can potentially prevent pathological reactions associated with consequences of stroke. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.
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  • 51
    Publikationsdatum: 2012-04-07
    Beschreibung: Anastatus japonicus Ashmead (Hymenoptera: Eupelmidae) is an important egg parasitoid of several major insect pests. To better understand its host finding mechanisms, the antennal sensilla of female wasp were investigated by scanning electron microscopy. Sensilla chaetica were found mainly on radicle and pedicel segments of the antennae. i-Type sensilla, s. campaniformia , and corneous sensilla were detected on the leeward side, while s. coeloconica and lance sensilla were presented on the windward side of the antennae. S. trichodea and s. basiconica were more abundant on the leeward side than on the windward side of the antennae. More s. placodea were found on the windward side than on the leeward side of the right antenna, while the opposite results were observed on the left antenna. Overall, more s. placodea were found on the right antenna than that on the left antenna. The numbers of s. trichodea and s. basiconica on the clava or the third flagellum antennomere of the right antenna were more than those of the left antenna, whereas their distribution patterns on the other corresponding antennomeres were reverse. Our results showed that there is a strong asymmetrical antennal sensilla distribution quantitatively and spatially between the left and right antennae. Placoid sensilla are present more on the right antenna than on the left antenna. S. campaniformia , corneous sensilla, and i-type sensilla were found only on the leeward side of the antennal clava, while their external morphology and potential functions were described and discussed in detail for the first time. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.
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  • 52
    Publikationsdatum: 2012-04-13
    Beschreibung: This research aimed to examine the morphological features of the tongue and laryngeal entrance of long-legged buzzard by macroscopic and scanning electron microscopic methods. Two adult buzzards were used as material. The tongue was fairly elongated and terminated in oval shovel-like apex. Scale-like projections were localized on the apex and body of tongue. Both lateral sides of lingual body were contained considerably long thread-like projections. Many orifices of lingual posterior salivary glands were discerned among scale-like projections in median sulcus of the lingual body. Papillary crest of sharp conical papilla were observed on the between the body and root of the tongue. No conical papillae or other projections were existent on the root of the tongue, but numerous orifices of posterior salivary gland ducts were detected. In addition, orifices of anterior salivary gland ducts were present on the dorsal and lateral surfaces of the lingual body. Numerous conical papillae were observed on the caudal region of glottis and no conical papillae or any similar projection which were bordered the glottic fissure was noted. Anatomy of these organs in the long-legged buzzard and white tailed eagle which are the member of the same family, Accipitridae, revealed very high similarity. Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc.
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  • 53
    Publikationsdatum: 2012-04-15
    Beschreibung: Anastatus japonicus Ashmead (Hymenoptera: Eupelmidae) is an important egg parasitoid of several major insect pests. To better understand its host finding mechanisms, the antennal sensilla of female wasp were investigated by scanning electron microscopy. Sensilla chaetica were found mainly on radicle and pedicel segments of the antennae. i-Type sensilla, s. campaniformia , and corneous sensilla were detected on the leeward side, while s. coeloconica and lance sensilla were presented on the windward side of the antennae. S. trichodea and s. basiconica were more abundant on the leeward side than on the windward side of the antennae. More s. placodea were found on the windward side than on the leeward side of the right antenna, while the opposite results were observed on the left antenna. Overall, more s. placodea were found on the right antenna than that on the left antenna. The numbers of s. trichodea and s. basiconica on the clava or the third flagellum antennomere of the right antenna were more than those of the left antenna, whereas their distribution patterns on the other corresponding antennomeres were reverse. Our results showed that there is a strong asymmetrical antennal sensilla distribution quantitatively and spatially between the left and right antennae. Placoid sensilla are present more on the right antenna than on the left antenna. S. campaniformia , corneous sensilla, and i-type sensilla were found only on the leeward side of the antennal clava, while their external morphology and potential functions were described and discussed in detail for the first time. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.
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  • 54
    Publikationsdatum: 2012-04-15
    Beschreibung: We have explored the effects of atmospheric environment on Kelvin force microscopy (KFM) measurements of potential difference between different regions of test polycrystalline diamond surfaces. The diamond films were deposited by microwave plasma-assisted chemical vapor deposition, which naturally produces hydrogen terminations on the surface of the films formed. Selected regions were patterned by electron-beam lithography and chemical terminations of oxygen or fluorine were created by exposure to an oxygen or fluorine plasma source. For KFM imaging, the samples were mounted in a hood with a constant flow of helium gas. Successive images were taken over a 5-h period showing the effect of the environment on KFM imaging. We conclude that the helium flow removes water molecules adsorbed on the surface of the samples, resulting in differences in surface potential between adjacent regions. The degree of water removal is different for surfaces with different terminations. The results highlight the importance of taking into account the atmospheric environment when carrying out KFM analysis. © 2012 Wiley Periodicals, Inc.
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  • 55
    Publikationsdatum: 2012-04-15
    Beschreibung: To evaluate the efficacy of ProTaper Universal rotary retreatment system and the influence of sealer type on the presence of filling debris in the reinstrumented canals viewed in an operative clinical microscope. Forty-five palatal root canals of first molars were filled with gutta-percha and one of the following sealers: G1, EndoFill; G2, AH Plus; G3, Sealapex. The canals were then reinstrumented with ProTaper Universal rotary system. Roots were longitudinally sectioned and examined under an operative clinical microscope (10×), and the amount of filling debris on canal walls was analyzed using the AutoCAD 2004 software. A single operator used a specific software tool to outline the canal area and the filling debris area in each third (cervical, middle, and apical), as well as the total canal area. Data were analyzed by Kruskal-Wallis test and Tukey test at P 〈 0.05. Sealapex demonstrated significant differences in the average of filling debris area/canal among the 3 thirds. This group revealed that apical third showed more debris than the both cervical and middle third ( P 〈 0.0001). Endofill presented significantly more filling debris than Sealapex in the cervical third ( P 〈 0.05). In the middle ( P = 0.12) and apical third ( P = 0.10), there were no differences amongst groups. Debris was left in all canal thirds, regardless of the retreatment technique. The greatest differences between techniques and sealers were found in the cervical third. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.
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  • 56
    Publikationsdatum: 2012-04-15
    Beschreibung: We have conducted a morphological study of the ampullae of Lorenzini on two shark species from Squatina Genus. In both species, S. guggenheim and S. occulta , the ampullae were observed like small pores scattered in the head region similar to other species of the Chondrichthyes Class. However, differently of the other species a greatest density of ampullae of Lorenzini was observed along of the body surface. After fixation using 10% formaldehyde, the ampullae were removed and processed for light and scanning electron microscopy. Macroscopically, the two shark species differed by the presence of dorsal spines that appeared from the head to the first dorsal fin in S. guggenheim and were absent in S. occulta . Microscopically, there were no differences between the ampullae of Lorenzini channels in these two species. The wall of the ampulla was formed by a simple squamous epithelium. Bands of connective tissue, hyaline cartilage and collagen fibers were found between the ampulla and the skeletal striated muscle layer. Nerve branches responsible for conducting signal pulses to the central nervous system were visible between the muscle and connective tissue layers. Using scanning electron microscopy and histological analysis, we found that the channels were twisted and positioned parallel to the skin. The inside of the channels contained a large amount of a gelatinous secretion composed by polysaccharides. Therefore, we conclude that the morphological combination of extended distribution of the ampullae of Lorenzini and the body shape may represent an adaptation of these species to their way of life. Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc.
    Print ISSN: 1059-910X
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  • 57
    Publikationsdatum: 2012-04-15
    Beschreibung: The low-shrink Silorane-based composite could bond effectively to bone and showed the potential be used as a bone cement. Bone organ culture maintains the anatomical order, natural cell-to-cell and cell-to-matrix relationship. The purpose of this study was to evaluate the responses of bone cells to a Silorane-based composite which was compared with a representative polymethyl methacrylate (PMMA) bone cement. The critical size defects were created through the parietal bones from one litter of mice. The paired bones were divided into two groups: Silorane-based composite group and PMMA group. The prepared two groups of disks were put into the defects. The cultures were grown in vitro for 38 days and analyzed with microcomputed-tomography, dissecting-microscope, phase- contrast-microscope, scanning-electron-microscopy, and energy- dispersive-X-ray. At the 10th day, the Silorane disk was almost fully covered by a sheet of cells but the cells hardly attached to the disk surface. The edge of the PMMA disk was covered by a sheet of cells and the migrated individual cells attached to the whole surface of the disk. At the 38th day, some cells attached to the exposed disk area of the Silorane disk while the formed tissues covered the whole surface of the PMMA disk. The collagen fibers, globular deposits and bone formation were visible in both groups. The Silorane-based composite showed promise as a potential bone cement when compared with PMMA which is used in clinical orthopedics. However, the cell attachment to PMMA was evidently better than to Silorane-based composite. Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc.
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  • 58
    Publikationsdatum: 2012-04-15
    Beschreibung: The aim of this study was to compare the percentage of gutta-percha (PGP) in mesial root canals of mandibular molars obturated with LC (Lateral Compaction) or SC (Single Cone) ProTaper Universal System techniques at different levels of the root. Mesial root canals of 20 human permanent molars with similar anatomical characteristics were instrumented using the ProTaper Universal rotary system technique until the F2 instrument, with 20 canals filled by SC ProTaper Universal technique and 20 canals by the LC technique. The mesial roots were sectioned transversely to 3, 5, and 7 mm from the root apex. Digital images of specimens were obtained at MIC-D digital microscope in increases of 30 to 35X. The gutta-percha area was measured using ImageTool software. Data were analyzed using two-way ANOVA and Bonferroni test (α = 0.05). The SC technique provided greater PGP than the LC technique in the apical third (3 mm) ( P 〈 0.001). In the other thirds (5 and 7 mm) there was no statistical difference between the two techniques regarding the PGP ( P 〉 0.05). There was no statistically significant difference between thirds of the root canal for both techniques ( P 〉 0.05). It was concluded that SC technique provided greater PGP than the LC technique in the apical third of mesial root canals of mandibular molars. There was no difference between the two techniques regarding the PGP in the cervical and middle thirds. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.
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  • 59
    Publikationsdatum: 2012-04-15
    Beschreibung: Stroke is associated with the intracerebral formation of fibrin clots which may lead to irreversible brain damage. Thrombolytic therapies employ a variety of natural and/or recombinant plasminogen activators to initiate fibrinolytic degradation of cerebral thrombi. However, such therapies when installed beyond 4- to 6-h window, may fail to achieve the expected outcome. This is due to the hydroxyl radical-induced modification of fibrin(ogen) molecules rendering them refractory to fibrinolytic degradation, but no cause of the increased free radical generation in stroke was offered. Here, we show by means of electron microscopy that iron ions added to human blood dramatically enhances fibrin fibers formation with thrombin, and significantly delays fibrinolysis during spontaneous clotting of native blood. Iron ions caused the appearance dense matted fibrin deposits, similar, if not identical, to those observed in plasma of patients with stroke. These results may explain a known relationship between thrombotic diseases and the increased body concentrations of free iron and/or hemoglobin derivatives. We conclude that any action resulting in the inhibition of hemostatic abnormalities, as well as in the reduction of body free iron and scavenging of hydroxyl radicals (e.g., by polyphenols) can potentially prevent pathological reactions associated with consequences of stroke. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.
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  • 60
    Publikationsdatum: 2012-04-15
    Beschreibung: For the study of cellular ultrastructure, the sample needs to be stabilized by fixation, with the ultimate aim to preserve the native tissue organization and to protect the tissue against later stages of preparation. Chemical and freezing fixation are most used, and chemical fixation employs agents that permeate tissues and cells by diffusion and covalently bind with their major biochemical constituents to fix them. Most widely used chemical fixatives are aldehydes, e.g., formaldehyde and glutaraldehyde, which are noncoagulating, crosslinking agents. Cryofixation methods for ultrastructural studies are also popular, and high-pressure freezing immobilizes all cell constituents and arrests biological activity by removing the thermal energy from the system. In the current research, we used platelet-rich plasma (PRP) to study expansive fibrin fibers and platelet ultrastructure to compare the two fixation techniques. We also used thrombin and calcium chloride as a clotting agent to determine the technique most suitable for the formation of extensive fibrin networks. Chemically fixated fibrin fibers were more compact and condensed and also showed a banding pattern on longitudinal sections. High-pressure frozen samples were more dispersed while platelets fixated showed better preserved cellular membranes and organelle structure. PRP coagulated by addition of CaCl 2 showed blood platelets that are noticeably more activated compared with PRP; however, with thrombin, a sharp ultrastructure was seen. We conclude that PRP mixed with thrombin, and freeze substituted, is the most suitable method for the study of extensive fibrin fibers as well as platelets. Microsc. Res. Tech. 2011. © 2011 Wiley Periodicals, Inc.
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  • 61
    Publikationsdatum: 2012-04-15
    Beschreibung: This study aimed to evaluate, ex vivo , the nanoleakage in dentinal tubules, the linear infiltration of silver nitrate in the dentin wall/root-end filling material interface, and the presence of gaps in this interface in root-end cavities filled with 4 filling materials. Forty-eight disto-buccal root canals of maxillary molars were instrumented and filled. Retrograde cavities were prepared with ultrasonic points (apical 2 mm). The samples were divided into 2 control groups ( n = 4) and 4 experimental groups ( n = 10): Group I – white mineral trioxide aggregate (MTA); Group II – Super EBA; Group III – Portland cement; and Group IV – Sealer 26. After 1 week, the specimens were subjected to silver nitrate and prepared for SEM (backscattered electrons). In the apical-apical segment, an area with significantly higher leakage was observed for Super EBA, followed by Portland cement, MTA, and Sealer 26 ( P = 0.0054). In the medium and cervical segments, all materials showed the same leakage behavior ( P = 0.1815 and P = 0.1723, respectively). The linear infiltration at the dentin wall/root-end filling material interface was higher with Super EBA than the other groups. No differences in the percentage of gaps along the 3 mm of dentin wall/root-end filling material interface between the 4 materials were evident ( P 〉 0.05). Nanoleakage occurred mainly in the apical segment of the samples, and Super EBA showed the highest values. The area and linear leakage were lower in the middle and coronal segments, regardless of the root-end filling material. No material perfectly sealed the root-end cavities, which allowed for the leakage occurrence. Microsc. Res. Tech., 2011. © 2011 Wiley Periodicals, Inc.
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  • 62
    Publikationsdatum: 2012-04-15
    Beschreibung: The umbilical cord blood (UCB) is an important source of hematopoietic stem cells with great deal of interest in regenerative medicine. The UCB cells have been extensively studied as an alternative to the bone marrow transplants. The challenge is to define specific methods to purify and characterize these cells in different animal species. This study is aimed at morphological characterization of progenitor cells derived from UCB highlighting relevant differences with peripheral blood of adult in dog and cats. Therefore, blood was collected from 18 dogs and 5 cats' umbilical cords from fetus in various developmental stages. The mononuclear cells were separated using the gradient of density Histopaque-1077. Characterization of CD34+ cells was performed by flow cytometric analysis and transmission electron microscopy. Granulocytes (ancestry of the basophiles, eosinophiles, and neutrophiles) and agranulocytes (represented by immature lymphocytes) were identified. We showed for the first time the ultrastructural features of cat UCB cells. Microsc. Res. Tech. , 2011. © 2011 Wiley Periodicals, Inc.
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  • 63
    Publikationsdatum: 2012-04-15
    Beschreibung: Purpose: This work aims to study the erosion on restorative materials and on surrounding dentin. Fifty root dentin samples were obtained from bovine incisors. Methods: Twenty samples were not restored and thirty received cavity preparations. Samples were assigned to five groups: G1, G2: sound dentin (D); G3: composite resin (CR); G4: resin-modified glass-ionomer cement (RMGIC); G5: glass-ionomer cement (GIC). The samples of groups 2–5 were submitted to six cycles (demineralization–remineralization). Samples were analyzed by micro energy-dispersive X-ray fluorescence spectrometry (μ-EDXRF) and by scanning electron microscopy (SEM). Results: Mineral loss was greater in G2 samples than in RMGI 〉 CR 〉 GIC 〉 D (control). SEM images showed pronounced dentin demineralization in groups 2 and 4. The acid erosion has a significant effect on mineral loss (Ca and P) of root dentin without restoration. Conclusions: Composite resin had the best chemical resistance to erosion among all the materials. Fluoride contained in GIC seemed to cause some protection, however, with material degradation. Chemical interaction of tooth-colored dental materials with root dentin could be assessed by μ-EDXRF. Microsc. Res. Tech., 2011. © 2011 Wiley Periodicals, Inc.
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  • 64
    Publikationsdatum: 2012-04-15
    Beschreibung: The aim of this study is to show histological and immunofluorescence analysis of renal parenchyma of agoutis affected by gentamicin-induced renal disease after the infusion of bone marrow mononuclear cells (BMMC) stained with Hoechst®. Nine agouti's males were divided into three groups: Test group (TG): renal disease by gentamicin induced ( n = 3), cell therapy group (CTG): renal disease by gentamicin induced and BMMC infusion ( n = 3), and control group (CG): nonrenal disease and BMMC infusion ( n = 3). TG and CTG were submitted to the protocol of renal disease induction using weekly application of gentamicin sulfate for 4 months. CG and CTG received a 1 × 108 BMMC stained with Hoechst and were euthanized for kidney examination 21 days after BMMC injection and samples were collected for histology and immunofluorescence analysis. Histological analysis demonstrated typical interstitial lesions in kidney similarly to human disease, as tubular necrosis, glomerular destruction, atrophy tubular, fibrotic areas, and collagen deposition. We conclude that histological analysis suggest a positive application of agouti's as a model for a gentamicin inducing of kidney disease, beyond the immunofluorescence analysis suggest a significant migration of BMMC to sites of renal injury in CTG. Microsc. Res. Tech., 2012. © 2011 Wiley Periodicals, Inc.
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  • 65
    Publikationsdatum: 2012-04-15
    Beschreibung: We present a modern, light portable device specifically designed for environmental samples for cryogenic transmission-electron microscopy (cryo-TEM) by on-site cryo-plunging. The power of cryo-TEM comes from preparation of artifact-free samples. However, in many studies, the samples must be collected at remote field locations, and the time involved in transporting samples back to the laboratory for cryogenic preservation can lead to severe degradation artifacts. Thus, going back to the basics, we developed a simple mechanical device that is light and easy to transport on foot yet effective. With the system design presented here we are able to obtain cryo-samples of microbes and microbial communities not possible to culture, in their near-intact environmental conditions as well as in routine laboratory work, and in real time. This methodology thus enables us to bring the power of cryo-TEM to microbial ecology. Microsc. Res. Tech., 2011. © 2011 Wiley Periodicals, Inc.
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  • 66
    Publikationsdatum: 2012-04-15
    Beschreibung: Functional restoration for orthopedic, systemic, or dental purposes uses a diverse range of biomaterials. Monitoring for any subsequent failures associated with pathology is vital. To this end, an alternative methodology beyond that of cutting sections by conventional microtome knife-based histomethodologies was pioneered. The method was to saw a block of tissue followed by grinding the unsupported slice to the required thickness. The sawing and grinding of unsupported bones or teeth exposed not only the specimen fragility, but also the delicacy of the associated soft tissues. Although incomplete, the significance of the technique was recognized and improvements were incorporated which persist to the present day addressing the histopathology of challenging specimens. One major improvement for preserving cellular structure as well as reducing fracture incidence was achieved by impregnating tissue samples with cross-linked resins prior to the cutting and grinding processes. Methyl and glycol methacrylate resins superseded all other choices because of the advantages of photo-initiated curing. Further pioneering work led to the formulation of increasingly appropriate resin systems and the subsequent processing protocols evolved, as clinical needs for histology-specific techniques became apparent. Over the decades, several key pioneers entered this scientific arena to develop the now established resin formulation, processing protocols, and allied applications. This has led to the commercialization of the various resin systems. The aim here is to discuss the commercially available glycol and methyl methacrylate resin systems and their practical application to a variety of important techniques used in the histological assessment of complex pathology specimens. Microsc. Res. Tech., 2012. © 2011 Wiley Periodicals, Inc.
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  • 67
    Publikationsdatum: 2012-04-15
    Beschreibung: Using live-cell confocal microscopy and particle tracking technology, the simultaneous transport of intracellular vesicles of the endo-lysosomal pathway and nonviral polyethylenimine (PEI)/DNA nanocomplexes was investigated. Due to potential problems associated with the use of acid-sensitive probes in combination with a gene vector that is hypothesized to buffer the pH of intracellular vesicles, the biological location of PEI/DNA gene vectors was revealed by probing their trafficking in cells expressing fluorescent versions of either early endosome antigen 1, a protein that localizes to early endosomes, or Niemann Pick C1, a protein that localizes to late endosomes and lysosomes. Studies directly show that PEI/DNA nanoparticles are actively transported within both early and late endosomes, and display similar overall transport rates in each. Additionally, gene vector transfer between endosomes is observed. Over time post-transfection, gene vectors accumulate in late endosomes/lysosomes; however, real-time escape of vectors from membrane-bound vesicles is not observed. Microsc. Res. Tech., 2012. © 2011 Wiley Periodicals, Inc.
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  • 68
    Publikationsdatum: 2012-04-15
    Beschreibung: Purpose: The aim of this study was to evaluate the nanoleakage patterns between dental enamel and reinforced leucite ceramic, bonded with resin luting systems and a flowable composite resin. Materials and Methods: Twelve crowns of bovine incisors were randomly divided into four groups ( n = 3) according to the luting procedure: Excite/Variolink II, Clearfil SE Bond/Panavia F, Scotchbond Multi-Purpose Plus/RelyX ARC, and Single Bond 2/Filtek Z350 Flow. To evaluate the nanoleakage patterns, IPS Empress Esthetic disks (5 mm Ø and 1.2-mm thick) were bonded to enamel, and, after 24 h, the specimens were immersed in a 50% (w/v) solution of silver nitrate (24 h), fixed, dehydrated, and processed scanning electron microscopy (SEM). Results: None nanoleakage on interface of the groups that Single Bond 2 followed by the flowable composite were used. The highest percentage of nanoleakage was shown by the Excite/Variolink II protocol. Also, in all conditions tested, none silver nitrate uptake was observed between the leucite-reinforced ceramic and the resin luting cement. Conclusions: The use of a two-step etch-and-rinse adhesive with flowable composite was able to promote an adequate seal of the bond interface at the enamel. Moreover, the conventional dual-cured resin cements associated with simplified and dual-cured adhesives tested are also indicated to bond thin ceramics to enamel, since all presented low silver nitrate uptake. Microsc. Res. Tech., 2012. © 2011 Wiley Periodicals, Inc.
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  • 69
    Publikationsdatum: 2012-04-15
    Beschreibung: This article reports a novel color tuning method by local sputtering nanolayers on microstructured porous alumina (PA) templates with different pore depths. With the aid of scanning electron microscopy observation, physical models of the original and sputtered PA templates are set up, and the details of the color tuning method are further proposed. Two series of colors covering the whole visible range are first obtained by respectively sputtering Cr and Ag nanolayers on two groups of PA templates with pore-depths ranging from 230 to 490 nm. A vivid colorful pattern of “Butterfly wings” is then prepared by local sputtering such Cr and Ag nanolayers on the surface of a PA with 310 nm pore-depth. The scanning electron microscopy images of Cr and Ag sputtered PA surfaces show different microstructures, which is in agreement with different color exhibiting. This method is expected to have a potential of being widely applied in the fields of micro-optics, microstructures, advanced materials, and micro/nanotechnology. Microsc. Res. Tech., 2012. © 2011 Wiley Periodicals, Inc.
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  • 70
    Publikationsdatum: 2012-04-13
    Beschreibung: To evaluate the efficacy of ProTaper Universal rotary retreatment system and the influence of sealer type on the presence of filling debris in the reinstrumented canals viewed in an operative clinical microscope. Forty-five palatal root canals of first molars were filled with gutta-percha and one of the following sealers: G1, EndoFill; G2, AH Plus; G3, Sealapex. The canals were then reinstrumented with ProTaper Universal rotary system. Roots were longitudinally sectioned and examined under an operative clinical microscope (10×), and the amount of filling debris on canal walls was analyzed using the AutoCAD 2004 software. A single operator used a specific software tool to outline the canal area and the filling debris area in each third (cervical, middle, and apical), as well as the total canal area. Data were analyzed by Kruskal-Wallis test and Tukey test at P 〈 0.05. Sealapex demonstrated significant differences in the average of filling debris area/canal among the 3 thirds. This group revealed that apical third showed more debris than the both cervical and middle third ( P 〈 0.0001). Endofill presented significantly more filling debris than Sealapex in the cervical third ( P 〈 0.05). In the middle ( P = 0.12) and apical third ( P = 0.10), there were no differences amongst groups. Debris was left in all canal thirds, regardless of the retreatment technique. The greatest differences between techniques and sealers were found in the cervical third. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.
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  • 71
    Publikationsdatum: 2012-04-13
    Beschreibung: The aim of this study was to compare the percentage of gutta-percha (PGP) in mesial root canals of mandibular molars obturated with LC (Lateral Compaction) or SC (Single Cone) ProTaper Universal System techniques at different levels of the root. Mesial root canals of 20 human permanent molars with similar anatomical characteristics were instrumented using the ProTaper Universal rotary system technique until the F2 instrument, with 20 canals filled by SC ProTaper Universal technique and 20 canals by the LC technique. The mesial roots were sectioned transversely to 3, 5, and 7 mm from the root apex. Digital images of specimens were obtained at MIC-D digital microscope in increases of 30 to 35X. The gutta-percha area was measured using ImageTool software. Data were analyzed using two-way ANOVA and Bonferroni test (α = 0.05). The SC technique provided greater PGP than the LC technique in the apical third (3 mm) ( P 〈 0.001). In the other thirds (5 and 7 mm) there was no statistical difference between the two techniques regarding the PGP ( P 〉 0.05). There was no statistically significant difference between thirds of the root canal for both techniques ( P 〉 0.05). It was concluded that SC technique provided greater PGP than the LC technique in the apical third of mesial root canals of mandibular molars. There was no difference between the two techniques regarding the PGP in the cervical and middle thirds. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.
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  • 72
    Publikationsdatum: 2012-04-15
    Beschreibung: The shallow-water bivalve Codakia orbiculata which harbors gill-endosymbiotic sulfur-oxidizing γ-proteobacteria can lose and acquire its endosymbionts throughout its life. Long-term starvation and recolonization experiments led to changes in the organization of cells in the lateral zone of gill filaments. This plasticity is linked to the presence or absence of gill-endosymbionts. Herein, we propose that this reorganization can be explained by three hypotheses: (a) a variation in the number of bacteriocytes and granule cells due to proliferation or apoptosis processes, (b) a variation of the volume of these two cell types without modification in the number, and (c) a combination of both number and cell volume variation. To test these hypotheses, we analyzed cell reorganization in terms of proliferation and apoptosis in adults submitted to starvation and returned to the field using catalyzed reporter deposition fluorescence in situ hybridization, immunohistochemistry, and structural analyses. We observed that cell and tissue reorganization in gills filaments is due to a variation in cell relative abundance that maybe associated with a variation in cell apparent volume and depends on the environment. In fact, bacteriocytes mostly multiply in freshly collected and newly recolonized individuals, and excess bacteriocytes are eliminated in later recolonization stages. We highlight that host tissue regeneration in gill filaments of this symbiotic bivalve can occur by both replication of existing cells and division of undifferentiated cells localized in tissular bridges, which might be a tissue-specific multipotent stem cell zone. © Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.
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  • 73
    Publikationsdatum: 2012-04-15
    Beschreibung: Mammalian choroid plexuses (CPs) are vascularized structures involved in numerous exchange processes that supply nutrients and hormones to the brain, and that remove deleterious compounds and metabolites from the brain. Studies in the adult Mediterranean buffalo have investigated the morphology of CPs using histochemical and immunohistochemical techniques. To date, however, there have been no studies conducted on ruminants regarding this removal process which serves to repair functional vascular damage in the CPs. Each of these vascular repair processes is a very complex and none of these has not yet been completely understood. Then, the aim of the present study is to investigate the morphological processes during angiogenesis in the CPs of healthy adult buffaloes, utilizing transmission electron microscopy (TEM), scanning electron microscopy (SEM), and immunogold-labeling SEM analysis (biomarkers: angiopoietin-2 [Ang-2], vascular endothelial growth factor receptor-3 [VEGFR-3], and CD133). At TEM, the inner surface of the blood capillaries sometimes showed pillar-like cells, which in contact with endothelial cells formed prominences, which in turn formed neo-blood capillaries. With immunogold-labeling SEM analysis, the CP blood capillaries showed Ang-2 and VEGF-3, respectively, in positive particles and spheroid formations. In addition, the external surface of the blood capillaries showed spheroid formations that originated from the neo-vascular capillaries whose terminals formed a capillary network, positive to CD133. On the basis of these results, the following hypothesis can be made, namely, that these CPs are vascular structures which play a fundamental role in maintaining brain homeostasis and self-repairing of functional vascular damage, independently of the presence of rete mirabile in this species. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.
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  • 74
    Publikationsdatum: 2012-04-15
    Beschreibung: Changes in physicochemical properties of the human hair shaft induced by UVB during the summer climate were investigated. Using atomic force microscopy and thermogravimetric analyzer measurements, we investigated the changes in hair shaft physical properties including morphology, roughness, and water content. The changes in chemical properties were investigated by using FTIR spectroscopy. Hair samples from 20 females without any chemical or physical stresses were investigated. The samples were exposed to various UVB doses of 400, 2,000, and 4,000 mJ/cm 2 , which correspond to the radiation times of 0.44, 2.22, and 4.44 h, respectively. The morphology and surface of the hair shaft was not significantly affected by UVB irradiation. The components of keratin were affected by the UVB irradiation where the amide A bands at 3,263 and 3,246 cm −1 of the proximal and distal roots, respectively, were shifted to higher band region because α-helix converted to β-sheet, and the stretching modes of C H lipid alkyl chains at 2,965 and 2,850 cm −1 in the proximal and distal roots, respectively, were developed. As the UVB intensity increased, the water content of the proximal root decreased. Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc.
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  • 75
    Publikationsdatum: 2012-04-15
    Beschreibung: Feature/edge-preserving noise removal techniques have a strong potential in several application domains including medical image processing. Magnetic resonance (MR) images have a tendency to gain Rician noise during acquisition. In this article, we have presented genetic algorithms based adapted selective non-local means (GASNLM) filter-based scheme for noise suppression of MR images while preserving the image features as much as possible. We have applied GASNLM filter with optimal parameter values for different frequency image regions to remove the noise. Filter parameter values are optimized by genetic algorithm (GA). A change in NLM filter known as selective weight matrix is also proposed to preserve the image features. The results prove soundness of the method. We have compared results with many well known and latest techniques, and the improvements are discussed. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.
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  • 76
    Publikationsdatum: 2012-04-15
    Beschreibung: The stretch zone width (SZW) data for 15-5PH steel CTOD specimens fractured at −150°C to + 23°C temperature were measured based on focused images and 3D maps obtained by extended depth-of-field reconstruction from light microscopy (LM) image stacks. This LM-based method, with a larger lateral resolution, seems to be as effective for quantitative analysis of SZW as scanning electron microscopy (SEM) or confocal scanning laser microscopy (CSLM), permitting to clearly identify stretch zone boundaries. Despite the worst sharpness of focused images, a robust linear correlation was established to fracture toughness ( K C ) and SZW data for the 15-5PH steel tested specimens, measured at their center region. The method is an alternative to evaluate the boundaries of stretched zones, at a lower cost of implementation and training, since topographic data from elevation maps can be associated with reconstructed image, which summarizes the original contrast and brightness information. Finally, the extended depth-of-field method is presented here as a valuable tool for failure analysis, as a cheaper alternative to investigate rough surfaces or fracture, compared to scanning electron or confocal light microscopes. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.
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  • 77
    Publikationsdatum: 2012-04-15
    Beschreibung: The aim of this study was to evaluate the healing process of intramembranous (IM) and endochondral (EC) bone grafts under low-level laser therapy (LLLT). Male rabbits underwent onlay autogenous bone grafts (1 cm in diameter) retrieved from the calvaria and iliac crest and fixed on parietal bones, divided into four groups: Calvaria (C), Iliac (I), Calvaria + LLLT (C+L), and Iliac + LLLT (I+L). Animals from C+L and I+L Groups had their grafts exposed to LLLT (AlGaAs–808 nm, CW, 30 mW, 0.028 cm 2 average laser beam area), 15 s irradiation time (16 J/cm 2 per point–total of 64 J/cm 2 per session). After 7, 14, 30, and 60 days, grafts were retrieved and resorption pattern analyzed by means of morphometry and TRAP-positive osteoclasts detection. Differences in the resorption levels of iliac grafts were observed, presenting 40% in I group against 8% in I+L grafts at the 14th day of evaluation ( P 〈 0.05). After 30 days, resorption was maintained at 41% in I group, whereas I+L presented 15% in the same period ( P = 0.0591). No significant differences were noted in the rates of calvaria grafts resorption in all periods. A significant higher number of osteoclasts on the grafts' surface was observed in C+L Group at day 30, in comparison with C group. In I+L Group, prevalence of osteoclasts was marked at day 7 ( P 〈 0.05) in comparison to I Group. In general, it was concluded that biomodulative effects of LLLT did not significantly affect healing and resorption processes of autogenous bone grafts from EC and IM origins. Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc.
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  • 78
    Publikationsdatum: 2012-04-15
    Beschreibung: This article explores the achievable transmission electron microscopy specimen thickness and quality by using three different preparation methods in the case of a high-strength nanocrystalline Cu–Nb powder alloy. Low specimen thickness is essential for spatially resolved analyses of the grains in nanocrystalline materials. We have found that single-sided as well as double-sided low-angle Ar ion milling of the Cu–Nb powders embedded into epoxy resin produced wedge-shaped particles of very low thickness (〈10 nm) near the edge. By means of a modified focused ion beam lift-out technique generating holes in the lamella interior large micrometer-sized electron-transparent regions were obtained. However, this lamella displayed a higher thickness at the rim of ≥30 nm. Limiting factors for the observed thicknesses are discussed including ion damage depths, backscattering, and surface roughness, which depend on ion type, energy, current density, and specimen motion. Finally, sections cut by ultramicrotomy at low stroke rate and low set thickness offered vast, several tens of square micrometers uniformly thin regions of ∼10-nm minimum thickness. As major drawbacks, we have detected a thin coating on the sections consisting of epoxy deployed as the embedding material and considerable nanoscale thickness variations. Microsc. Res. Tech., 2011. © 2011 Wiley Periodicals, Inc.
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  • 79
    Publikationsdatum: 2012-04-15
    Beschreibung: Myoepithelial cells (MECs) mainly surround acini and intercalated ducts in the human salivary glands. The contraction of MECs provides the expulsive force to promote salivation. We previously found functional transient receptor potential vanilloid subtype 1 (TRPV1) was expressed in rabbit and human submandibular glands and increased saliva secretion. However, it was unknown whether TRPV1 was expressed in MECs of submandibular glands. In this study, we observed the immunoflourescence of TRPV1 was not only located in serous acini and ducts but also surround the basal layer of the acinus and intercalated ducts of human submandibular glands. Double immunofluorescence staining revealed colocalization of TRPV1 with calponin, vimentin, and α-smooth muscle actin, which indicated the myoepithelial expression of TRPV1. Treating submandibular gland tissues with capsaicin, an agonist of TRPV1, substantially increased the phosphorylation of the 20-kDa regulatory light-chain subunit of myosin (MLC 20 ), a crucial molecule for contraction of smooth muscle cells, in MECs. Pretreatment with capsazepine, a specific TRPV1 inhibitor, blocked capsaicin-induced MLC 20 phosphorylation. These results suggest that TRPV1 is expressed in MECs of the human submandibular gland and mediates myoepithelial contraction via a mechanism involving MLC 20 phosphorylation. Microsc. Res. Tech., 2012. © 2011 Wiley Periodicals, Inc.
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  • 80
    Publikationsdatum: 2012-04-15
    Beschreibung: To determine whether sodium hypochlorite (NaOCl) with 0.2% chlorhexidine gluconate (CHX) leads to colour change and precipitate formation, and to ultrastructurally analyse the dentine surface after simultaneous irrigation with 0.5% NaOCl and 0.2% CHX. Four tubes in which 5ml of different NaOCl concentrations and 5ml 0,2% CHX were placed, were observed every 15 minutes in the first two hours and after 7 days. Mixture solutions were centrifuged at 800 rpm/4 min. A precipitate is observed under light-microscopy. Thirty-five single-rooted teeth were instrumented using crown-down technique with irrigation: Positive control: distilled water, Negative control: 0,5% NaOCl+15% EDTA, Experimental group: identical to the negative control, then canals were treated with 0.5% NaOCl+0.2% CHX. The longitudinal root sections were observed under scanning-electron-microscopy. The amount of debris was assessed with 5/score-system, and the results were analysed using the Mann-Whitney U test (p 〈 0.001). Change in colour was noticed immediately after the merger and it did not change with time. Mixture solutions showed considerable turbidity, but precipitate was observed only after centrifugation. Statistical analysis showed a significant difference in the dentinal wall purity when comparing the cervical and middle root canal thirds between the experimental and negative control group. The difference was also observed between the cervical and middle thirds compared to the apical third of the root canal within these groups. Interaction between NaOCl and CHX, as well as the creation of precipitates, depends not only on the concentration of NaOCl, but also on the concentration of CHX. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.
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  • 81
    Publikationsdatum: 2012-04-15
    Beschreibung: Frictional interactions between wires and brackets reduce the efficacy in orthodontic treatments. Self-ligating brackets (SLBs) are now more often used due to lower frictional forces when compared with conventional-ligating brackets. In this study, scanning electron microscopy and atomic force microscopy were used to examine the microstructural effects of stainless steel and ceramic SLBs on the surface roughness of stainless steel and superelastic NiTi wires both after in vivo clinical orthodontic treatment as well as in in vitro three-point bending experiments. A combination of two wires—0.019 in. × 0.025 in. stainless steel wires and 0.016 in. superelastic NiTi wires—and two SLBs—both passive-type stainless steel SLBs and active-type ceramic SLBs—was applied for 4 months (bicuspid-extraction) in an in vivo setting and for 1 month in an in vitro setting (200 g loads). After the SLB treatments, all wires exhibited severe scratches secondary to frictional interactions with the brackets. When used with the stainless steel SLBs (Damon 3MX®), the surfaces of 0.019 in. × 0.025 in. stainless steel ( P 〈 0.0001) and 0.016 in. superelastic NiTi wires ( P 〈 0.05) were significantly smoother than when used with the ceramic SLBs (Clippy-C®). Such results suggest that orthodontic treatments with stainless steel SLBs are more effective than with ceramic SLBs. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.
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  • 82
    Publikationsdatum: 2012-04-15
    Beschreibung: Virus particles and viral inclusions were detected by transmission electron microscopy examination of sections of the seminal vesicles and mucus gland of asymptomatic young drones from colonies of Apis mellifera lightly infested by Varroa mite. In the mucus gland the infection was found in the muscular sheath and epithelium, while in the seminal vesicle in cells of the outer serosa. Isolated viral particles were also observed in the hemolymph occupying the intercellular spaces of the muscular sheath fibers. In the muscle the virus appeared as polygonal crystalloid inclusions, while in the epithelium mainly inside cytoplasmic vesicles. The infected cells apparently are not damaged. The virus particles are present in the hemolymph and forming more mature structures, as crystalloids, in the muscle. This suggests that the virus is liberated in the body fluid and infects the tissues penetrating the cells through endocytosis. The presence of virus in mucus gland epithelial vesicles raise the possibility of its transference to the gland secretion and therefore, to the semen. Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc.
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  • 83
    Publikationsdatum: 2012-04-15
    Beschreibung: This study evaluated the effects on human enamel after two bleaching procedures: with a fluoridated bleaching agent and with topical fluoride application postbleaching. It used 43 enamel blocks (3 mm 2 ) that were ground flat (600–2,000 grit) and polished with polishing paste (one and one-fourth). Specimens were randomly divided into three groups according to the bleaching procedure: (1) control group, (2) hydrogen peroxide 35% (HPF) and topical application of fluoride 1.23%, and (3) HP 38% (OP) with fluoride in its composition. Bleaching agents were used according to the manufacturer's instructions. Three methodologies were used: nanoindentation, to observe surface hardness and elastic modulus; atomic force microscopy, to observe surface roughness ( R a − R z ); and scanning electron microscopy, to observe the enamel surface effects. Group OP had a decrease in the elastic modulus after bleaching, which was recovered at 14 days. An increased roughness ( R a ; 32%) was observed on group HPF and had an increased erosion on enamel surface (67%). It was concluded that topical application of fluoride, after using the nonfluoridated whitening agent, increased the roughness values and erosion of enamel. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.
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  • 84
    Publikationsdatum: 2012-04-15
    Beschreibung: Ticks are ectoparasites of great medical and veterinary importance around the world and synthetic chemicals such as permethrin have been used for their control. This study provides a cytochemistry analysis of both degenerative and cell death processes in salivary glands of the brown dog tick Rhipicephalus sanguineus semi-engorged females exposed to 206, 1,031, and 2,062 ppm of permethrin. The results presented herein demonstrate that permethrin is a potent chemical acaricide that would act on the glandular tissue's morphophysiology in this tick species by eliciting severe changes in the acinus shape, intense vacuolation of the acinar cells' cytoplasm, marked glandular tissue disorganization, culminating in an advanced degenerative stage with consequent formation of many apoptotic bodies (cell death). In addition, permethrin induced major changes in the acinar cells' nucleus, such as a change both in its shape and size, chromatin marginalization, nuclear fragmentation, and appearance of picnotic nuclei, especially when the highest concentrations of the product were used. Thus, permethrin induced early degeneration of this tissue characterized by significant changes in the structure of acinar cells and production of enzymes related to the cell death process, in addition to interfering directly in the genetic material of these cells. Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc.
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  • 85
    Publikationsdatum: 2012-04-15
    Beschreibung: Nanofillers are added to dental adhesives to improve mechanical properties of the hybrid layer. Ethanol or water added to the demineralized dentin to improve adhesive infiltration may produce filler aggregation. OBJECTIVE: To assess the effect of 5 vol% water or ethanol addition on nanoparticles distribution in dental adhesives. METHODS: Six available commercial adhesives systems were selected: Clearfil SE Bond (CSE), Clearfil Protect Bond (CPB), FL-Bond (FLB), Clearfil S3 (CS3), Bond Force (BF), One Up Bond F plus (OUB), and an experimental adhesive system without filler (EXP). Polymer films were obtained by adding 0 (control) or 5 vol% water or ethanol into the bonding resins. Preparations were light-cured (40 s). Three specimens were analyzed for each mixture. Three phases and 3D images were taken from each specimen by means of an atomic force microscope in taping mode (TM/AFM). Cluster sizes and surface nanoroughness were assessed. RESULTS: Control specimens from CSE, FLB, OUB, and BF presented clusters. The addition of solvents lead to particles aggregation in tested bonding resins. Ethanol addition produced more aggregates, particularly in adhesives containing fluoraluminosilicate as fillers. CONCLUSIONS: Nanofillers aggregation occurred in all adhesive systems in presence of additional solvents. In general, aggregate sizes were higher after the addition of ethanol. Formed clusters size values are always above the dimensions of the spaces existing between the demineralized collagen fibers. Microsc. Res. Tech. , 2011. © 2011 Wiley Periodicals, Inc.
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  • 86
    Publikationsdatum: 2012-04-15
    Beschreibung: In this article, the reproductive system's morphology of three young animals of the species Saguinus midas , from the bauxite mine in Paragominas, is described. The specimens were fixed and preserved in a solution of 10% aqueous formaldehyde, followed by dissection, measurement of the genital organs (uterus, vagina, ovaries, and uterine tubes), and histological processing. The vulva is delimited by the labia, with a clitoris. It is lined by keratinized stratified squamous epithelium with sebaceous glands of holocrine secretion. The vagina is an elongated tube with an average length of 26 mm and diameter of 1 mm, presenting a non-keratinized squamous epithelium, disposed between the vestibule of the vagina and cervix, the latter being relatively short. The uterus is simple, has globular shape and is located in the caudal portion of the abdominal cavity, with an average length of 14 mm and average width of 7 mm. It is formed by vascular and serous layers of muscles, and undergoes a bifurcation to form two structures on the bottom of blind sac. The uterine tubes are long and convoluted with an average length of 35 mm (right) and 36 mm (left), consisting of loose connective tissue and muscle layer lined by simple ciliated columnar epithelium. The ovaries are large and ellipsoid with smooth surface. Histologically, one animal showed ovulation fosse. Microsc. Res. Tech., 2011. © 2011 Wiley Periodicals, Inc.
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  • 87
    Publikationsdatum: 2012-04-15
    Beschreibung: The highly complex techniques of electron microscopy made it bound to the sensitive and critical micrograph analysis. The accurately interpreted micrographs are of paramount values in basic investigations. Interpretation skills and quality of the micrographs are the two fundamental keys in accomplishment of these goals but there are many mistakes and errors that can happen during the sample preparation, sectioning, EM operation, and photo publishing. The mentioned mistakes and errors effect directly in the final result which is a micrograph and can lead the analyzer who can be a pathologist to an interpretation followed by serious danger for patient. Artifacts caused by any given stimuli expected to be bothersome for investigators. Even best qualified equipments can be regarded as source of artifact generation. In this article, seven serious errors in electron micrographs which usually occur in transmission electron microscopy are addressed. Microsc. Res. Tech., 2012. © 2011 Wiley Periodicals, Inc.
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  • 88
    Publikationsdatum: 2012-04-15
    Beschreibung: Full-field hard X-ray tomography could be used to obtain three-dimensional (3D) nanoscale structures of biological samples. The image of the fission yeast, Schizosaccharomyces pombe , was clearly visualized based on Zernike phase contrast imaging technique and heavy metal staining method at a spatial resolution better than 50 nm at the energy of 8 keV. The distributions and shapes of the organelles during the cell cycle were clearly visualized and two types of organelle were distinguished. The results for cells during various phases were compared and the ratios of organelle volume to cell volume can be analyzed quantitatively. It showed that the ratios remained constant between growth and division phase and increased strongly in stationary phase, following the shape and size of two types of organelles changes. Our results demonstrated that hard X-ray microscopy was a complementary method for imaging and revealing structural information for biological samples. Microsc. Res. Tech., 2012. © 2011 Wiley Periodicals, Inc.
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  • 89
    Publikationsdatum: 2012-04-15
    Beschreibung: Bone marrow is a source of stem cells for greater and easier access, which is widely studied as a provider of hematopoietic and mesenchymal cells for various purposes, mainly therapeutic by the advances in research involving cell therapy. The swine is an animal species commonly used in the pursuit of development of experimental models. Thus, this study aimed to standardize protocol for collection and separation of bone marrow in swines, since this species is widely used as experimental models for various diseases. Twelve animals were used, which underwent bone marrow puncture with access from the iliac crest and cell separation by density gradient followed by a viability test with an average of 98% of viable cells. Given our results, we can ensure the swine as an excellent model for obtaining and isolation of mononuclear cells from bone marrow, stimulating several studies addressing the field of cell therapy. Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc.
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  • 90
    Publikationsdatum: 2012-04-15
    Beschreibung: Potentilla fulgens , a member of the family Rosaceae, has been known since ancient times in Northeast India for its antiparasitic, antitumour and antidiabetic properties. The crude ethanolic extract of the plant was assayed against Raillietina echinobothrida , the intestinal cestode parasite of domestic fowl to authenticate the putative anthelmintic efficacy and cestocidal potential in particular of the plant. Treatment of the worm in-vitro with 25, 50 and 100 mg of crude extract per ml of phosphate buffered saline caused paralysis leading to death taking 4.02–4.20, 3.05–3.75 and 2.05–2.83 h respectively. Scanning electron microscopic observations on treated worms revealed deformation of surface architecture, particularly in scolex and surface microtriches. Severe distortion and disorganization of the tegumental and subtegumental layer along with cytoplasmic organelle was also observed under transmission electron microscope. The possible use of the plant as a potential anthelmintic against cestode parasite is discussed. Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc.
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  • 91
    Publikationsdatum: 2012-04-15
    Beschreibung: In most anatomical studies developed with mammals, the tongue is described as highly differentiated among different species. However, studies on the tongue of aquatic mammals are still limited as compared to those on terrestrial mammals. The aim of this study was to describe the tongue morphology of the Franciscana dolphin ( Pontoporia blainvillei ) using macroscopic observations, light, and scanning electron microscopy. Microscopically, the dorsal surface was covered by a keratinized stratified epithelium. Salivary gland acini were found on the middle and caudal third of the tongue. The dorsal surface was totally covered by filiform papillae with a connective tissue core and a connective tissue structure round in shape in the middle and caudal regions. Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc.
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  • 92
    Publikationsdatum: 2012-04-15
    Beschreibung: OBJECTIVES: To compare microleakage of three self-etch adhesives and to analyze enamel surface morphology and interfacial morphology of resin–enamel and resin–dentin interface under scanning electron microscope (SEM). EXPERIMENTAL DESIGN: Study was conducted in 65 extracted human premolars. Class V cavities were prepared in 45 teeth and assigned to three groups ( n = 15) according to three self-etch adhesives (OptiBond All-in-One, iBond, and Adper Prompt L-Pop). After restoration, 10 samples from each group were used to assess microleakage at enamel and dentin margin. Five samples from each group were used for analysis of interfacial morphology at resin–enamel and resin–dentin interface under SEM. Remaining 20 teeth were used to prepare flat enamel buccal surfaces to analyze the difference in surface morphology after treatment with three adhesives ( n = 5 each) and 36% phosphoric acid treatment ( n = 5). PRINCIPAL OBSERVATIONS: At enamel margin, Prompt L-Pop depicted least leakage of all the three adhesives and also showed best interfacial adaptation under SEM. At dentin margin, OptiBond All-in-One showed significant less leakage than iBond and Prompt L-Pop. On flat enamel surface, phosphoric acid produced the most retentive etching pattern when compared with the three adhesives. CONCLUSION: Prompt L-Pop showed the best bonding effectiveness in enamel, whereas OptiBond All-in-One performed significantly better in dentin. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.
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  • 93
    Publikationsdatum: 2012-04-15
    Beschreibung: The transient receptor potential (TRP) channels are involved in sensing mechanical/physical stimuli such as temperature, light, pressure, as well as chemical stimuli. Some TRP channels are present in the vertebrate retina, and the occurrence of the multifunctional channel TRP vanilloid 4 (TRPV4) has been reported in adult zebrafish. Here, we investigate the expression and distribution of TRPV4 in the retina of zebrafish during development using polymerase chain reaction (PCR), Western blot, and immunohistochemistry from 3 days post fertilization (dpf) until 100 dpf. TRPV4 was detected at the mRNA and protein levels in the eye of zebrafish at all ages sampled. Immunohistochemistry revealed the presence of TRPV4 in a population of the retinal cells identified as amacrine cells on the basis of their morphology and localization within the retina, as well as the co-localization of TRPV4 with calretinin. TRPV4 was first (3 dpf) found in the soma of cells localized in the inner nuclear and ganglion cell layers, and thereafter (10 dpf) also in the inner plexiform layer. The adult pattern of TRPV4 expression was achieved by 40 dpf the expression being restricted to the soma of some cells in the inner nuclear layer and ganglion cell layers. These data demonstrate the occurrence and developmental changes in the expression and localization of TRPV4 in the retina of zebrafish, and suggest a role of TRPV4 in the visual processing. Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc.
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  • 94
    Publikationsdatum: 2012-04-15
    Beschreibung: Diplopods are agile saprophagous invertebrates with the ability to colonize several soil layers. They feed on waste and decaying organic matter, making the soil in which they are present better aerated and mineral-enriched. Because of their habits, diplopods have been suggested to be used in studies to analyze possible toxic effects of impacted soils in edafic fauna. In that respect, this study aimed at checking the feasibility of using morphological analysis from millipede's midgut as a biomarker for soils exposed to sewage sludge from sewage treatment plants. Histological and histochemical techniques, applied to the species Rhinocricus padbergi 's midgut, were used. Two sewage sludge samples were used; they were collected in two small towns in the countryside of São Paulo State. Both cities are part of the Piracicaba–Capivari–Jundiaí basin (PCJ-1 and PCJ-3). For 7 and 15-day periods, the animals were exposed to 10% concentrations and crude sludge for the PCJ-1sample and to 1, 10, and 50% concentrations and sludge for the PCJ-3 sample. The material exposed to the PCJ-1 sample showed an increase in the presence of cytoplasmic granules in both concentrations in all periods and a slight increase in the rate of epithelial renewal. The material of PCJ-3 sample presented the same alterations observed in PCJ-1 sample in higher frequence and over that high quantity of neutral polysaccharides in the hepatic cells layer. We can conclude that with the increase of sewage sludge concentrations tested, there is an increase in morphophysiologicals alterations frequencies found in the diplopods' midgut. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.
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  • 95
    Publikationsdatum: 2012-04-15
    Beschreibung: Colon layers, especially the submucosa, as well as the secretion of goblet cells are extremely important for the functioning and transit of substances in this organ. However, the damages arising from type I diabetes and the effects of physical training, which plays crucial role in the treatment of this disease, are not yet known in these regions. To analyze the changes in colon submucosa and goblet cells of diabetic rats, as well as the effects of physical training, Wistar rats were divided into four groups: sedentary control, trained control, sedentary diabetic (SD), and trained diabetic (TD). The training protocol consisted of swimming for 60 min a day, 5 days per week, during 8 weeks. Colon samples were collected, processed, and evaluated by histochemical and ultrastructural techniques. Goblet and submucosa cells did not show alterations in shape, size, protein and carbohydrate content, in all treatment groups. Decreased amount of collagen fibers, however, was observed in the submucosa and lamina propria of SD rats, but this alteration was recovered in TDs. The ultrastructural analysis, in turn, revealed greater quantity of Golgi apparatus cisterns in SDs, distinctly than TDs, which showed improvement in this diabetic condition. Thus, physical training was responsible for the recovery of some important diabetic alterations, possibly improving the motility of substances in the large intestine. Nevertheless, it cannot be considered alone in the treatment of this disease, requiring the combined practice of other methods. Microsc. Res. Tech., 2011. © 2011 Wiley Periodicals, Inc.
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  • 96
    Publikationsdatum: 2012-04-15
    Beschreibung: Brazilian endemic species Diplodon expansus (Küster, 1856) is found in freshwater bodies in the country's southeast, in large anthropogenic influence regions especially with an extensive agriculture emphasis. One of the main pesticides used in the species occurrence region is the atrazine herbicide, which has a great contamination potential in the aquatic environment. Therefore, several studies into its toxicity in aquatic systems have been developed. However, the tested concentrations are usually very high and rarely found in the environment and the short-term exposure responses in other aquatic organisms such as native bivalves are still scarce. Thus, this study sought to consider the potential effects of environmentally realistic concentrations of atrazine herbicide on the surface morphology of gill filaments of the bivalve D. expansus under laboratory-controlled conditions after short-term exposure. None of the animals died before the end of the experiment. The main alterations were observed on the frontal surface of filaments, which include mucus accumulation, cilia loss, and disruption. Mucus increased secretion and accumulation in the frontal filaments region preceded as a protective mechanism. Cilia loss and disruption on the frontal surface of the gill filament indicated that ciliated frontal cells were more sensitive to atrazine exposure and these alterations may cause gills functional damages, compromising the uptake of food particles and respiration. Therefore, higher sublethal concentrations of atrazine may compromise the survival and consequently the population of D. expansus in agriculture areas after a longer period of continuous exposure. Microsc. Res. Tech. 2011. © 2011 Wiley Periodicals, Inc.
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  • 97
    Publikationsdatum: 2012-04-15
    Beschreibung: This study presents the morpho-histological and histochemical characterization of the testes, integument, Malpighian tubules, and midgut of engorged Rhipicephalus sanguineus nymphs on the detachment day, showing the morphological and physiological characteristics to this phase in the life cycle of these individuals. The testis is constituted by germinative cells (only spermatogonia) with large, round-shaped and strongly stained nuclei which are organized into cysts by a thin layer of somatic cells. The integument consists of a cuticle subdivided into epicuticle (lipoprotein) and procuticle (glycoproteic), and a layer of epithelial cells which present glycolipoprotein elements. The procuticle presents two distinct regions: the exocuticle (next to the epicuticle) and the endocuticle (next to the epithelial layer). The Malpighian tubules present a simple epithelium with small flat and/or cubic cells, which form its wall and delimitates a lumen full of lipoprotein material. The midgut consists of an epithelial wall formed by two types of digestive cells, spent cells and empty digest cells, and by generative cells supported by a basal lamina and a thin layer of muscular tissue. This study described the main organs of engorged nymphs of R. sanguineus , to generate information that can help researchers to better understand the biology of these ectoparasites; which is fundamental for the development of compounds that are less aggressive to the environment. In addition, if the immature stages of the ticks are controlled, the number of adult ticks able to cause damages to the animals—and to the man as well—is also under control. Microsc. Res. Tech. 2011. © 2011 Wiley Periodicals, Inc.
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  • 98
    Publikationsdatum: 2012-04-15
    Beschreibung: Scanning electron microscopy (SEM) can be used to analyze the presence of debris and smear layer on the internal walls of root canal. This study evaluated the debris and smear removal in flattened root canals using SEM after use of different irrigant agitation protocols. Fifty mandibular incisors were distributed into five groups ( n = 10) according to the irrigant agitation protocol used during chemomechanical preparation: conventional syringe irrigation with NaviTip needle (no activation), active scrubbing of irrigant with brush-covered NaviTip FX needle, manual dynamic irrigation, continuous passive ultrasonic irrigation, and apical negative pressure irrigation (EndoVac system). Canals were irrigated with 5 mL of 2.5% NaOCl at each change of instrument and received a final flush with 17% EDTA for 1 min. After instrumentation, the roots were split longitudinally and SEM micrographs at ×100 and ×1,000 were taken to evaluate the amount of debris and smear layer, respectively, in each third. Data were analyzed by Kruskal–Wallis and Dunn's post-hoc tests (α = 5%). Manual dynamic activation left significantly ( p 〈 0.05) more debris inside the canals than the other protocols, while ultrasonic irrigation and EndoVac were the most effective ( p 〈 0.05) for debris removal. Regarding the removal of smear layer, there was no statistically significant difference ( p 〉 0.05) either among the irrigant agitation protocols or between the protocol–canal third interactions. Although none of the irrigant agitation protocols completely removed debris and smear layer from flattened root canals, the machine-assisted agitation systems (ultrasound and EndoVac) removed more debris than the manual techniques. Microsc. Res. Tech., 2011. © 2011 Wiley Periodicals, Inc.
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  • 99
    Publikationsdatum: 2012-04-15
    Beschreibung: Background: The early detection of neoplasia is the prime aim of a diagnostician. Altered chromatin distribution is the earliest microscopic change observed in malignant transformation making it a valuable morphometric parameter. This study was aimed to assess and correlate the progressive changes in chromatin texture from normal to varying grades of premalignancies to malignancy of the oral cavity. Methods: Thirty-four archival tissue specimens categorized as normal buccal mucosa (5), low-grade epithelial dysplasia (11), high-grade epithelial dysplasia (7), and squamous cell carcinoma (11) were stained with Feulgen reaction. Pixel optical densitometry histograms were obtained from analysis of an average of 300 cells/case using ImageJ software. Nine histogram curve characteristics (including area under the curve, area integer percentage, center, centroid) were then analyzed statistically for differences between the four groups. Results: Area integer percentage ( P = 0.002), center ( P = 0.038), and centroid ( P = 0.021) were statistically significant within the four groups The parameters showed a dip in their value from normal to low-grade dysplasia but showed a steady increase in high-grade dysplasia and carcinoma. Conclusion: The optical density characteristics had the ability to differentiate the progression of neoplastic changes by extracting information of the chromatin distribution not quantifiable by routine microscopy. The early clumping of chromatin in the periphery in low-grade dysplasia followed by progressively increasing chromatin aggregates in high-grade dysplasia and carcinoma correlated well with the shift observed in the histogram center and centroid. The novel pixel optical densitometry technique efficiently predicted malignant transformation. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.
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  • 100
    Publikationsdatum: 2012-04-15
    Beschreibung: In this study, we aimed to increase the sensitivity of protein labeling using 1.4 nm gold nanoparticles and glutamate δ2 receptor (GluD2) from the postsynaptic membrane of the Purkinje cells. The very small marker size of the particles reduces the steric hindrance between antibodies leading to a higher labeling efficiency of more than one subunit per single receptor molecule. The nanoparticles are visible in 200 kV dark-field scanning transmission electron microscope on freeze-fractured carbon replica of nervous tissue after plasma cleaning treatment. The different elemental composition of nanoparticles as Au nanogold or CdS quantum dot can be distinguished by energy dispersive X-ray spectroscopy. This method ensures detection of an average of three subunits per GluD2 and often labels all four of them with 1.4 nm Au nanoparticles. It is concluded that this high-resolution microscopic method is useful for exploring the quaternary structure of membrane proteins. Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc.
    Print ISSN: 1059-910X
    Digitale ISSN: 1097-0029
    Thema: Allgemeine Naturwissenschaft
    Publiziert von Wiley
    Standort Signatur Erwartet Verfügbarkeit
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