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  • Artikel  (39)
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  • Immunohistochemistry  (29)
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  • 1
    Digitale Medien
    Digitale Medien
    Piecewise linear test functions for stability and instability of queueing networks (1997)
    Springer
    Queueing systems 27 (1997), S. 205-226 
    Details
    ISSN: 1572-9443
    Schlagwort(e): multiclass queueing networks ; ergodicity ; stability ; performance analysis
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Informatik
    Notizen: Abstract We develop the use of piecewise linear test functions for the analysis of stability of multiclass queueing networks and their associated fluid limit models. It is found that if an associated LP admits a positive solution, then a Lyapunov function exists. This implies that the fluid limit model is stable and hence that the network model is positive Harris recurrent with a finite polynomial moment. Also, it is found that if a particular LP admits a solution, then the network model is transient.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1019166115653
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  • 2
    Digitale Medien
    Digitale Medien
    On the stability of retrial queues (1997)
    Springer
    Queueing systems 26 (1997), S. 343-363 
    Details
    ISSN: 1572-9443
    Schlagwort(e): retrial queues ; stability ; ergodicity ; renovation
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Informatik
    Notizen: Abstract We consider the following Type of problems. Calls arrive at a queue of capacity K (which is called the primary queue), and attempt to get served by a single server. If upon arrival, the queue is full and the server is busy, the new arriving call moves into an infinite capacity orbit, from which it makes new attempts to reach the primary queue, until it finds it non-full (or it finds the server idle). If the queue is not full upon arrival, then the call (customer) waits in line, and will be served according to the FIFO order. If λ is the arrival rate (average number per time unit) of calls and μ is one over the expected service time in the facility, it is well known that μ 〉 λ is not always sufficient for stability. The aim of this paper is to provide general conditions under which it is a sufficient condition. In particular, (i) we derive conditions for Harris ergodicity and obtain bounds for the rate of convergence to the steady state and large deviations results, in the case that the inter-arrival times, retrial times and service times are independent i.i.d. sequences and the retrial times are exponentially distributed; (ii) we establish conditions for strong coupling convergence to a stationary regime when either service times are general stationary ergodic (no independence assumption), and inter-arrival and retrial times are i.i.d. exponentially distributed; or when inter-arrival times are general stationary ergodic, and service and retrial times are i.i.d. exponentially distributed; (iii) we obtain conditions for the existence of uniform exponential bounds of the queue length process under some rather broad conditions on the retrial process. We finally present conditions for boundedness in distribution for the case of nonpatient (or non persistent) customers.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1019193527040
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  • 3
    Digitale Medien
    Digitale Medien
    Stable Sampled-data Adaptive Control of Robot Arms Using Neural Networks (1997)
    Springer
    Journal of intelligent and robotic systems 20 (1997), S. 131-155 
    Details
    ISSN: 1573-0409
    Schlagwort(e): robot adaptive control ; basis function-like networks ; stability ; discrete variable structure
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Informatik , Maschinenbau
    Notizen: Abstract Stable neural network-based sampled-data indirect and direct adaptivecontrol approaches, which are the integration of a neural network (NN)approach and the adaptive implementation of the discrete variable structurecontrol, are developed in this paper for the trajectory tracking control ofa robot arm with unknown nonlinear dynamics. The robot arm is assumed tohave an upper and lower bound of its inertia matrix norm and its states areavailable for measurement. The discrete variable structure control servestwo purposes, i.e., one is to force the system states to be within the stateregion in which neural networks are used when the system goes out of neuralcontrol; and the other is to improve the tracking performance within the NNapproximation region. Main theory results for designing stable neuralnetwork-based sampled data indirect and direct adaptive controllers aregiven, and the extension of the proposed control approaches to the compositeadaptive control of a flexible-link robot is discussed. Finally, theeffectiveness of the proposed control approaches is illustrated throughsimulation studies.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1007900125801
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  • 4
    Digitale Medien
    Digitale Medien
    Forward Assembly Planning Based on Stability (1997)
    Springer
    Journal of intelligent and robotic systems 19 (1997), S. 411-436 
    Details
    ISSN: 1573-0409
    Schlagwort(e): assembly planning ; stability ; robot ; forward ; operations
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Informatik , Maschinenbau
    Notizen: Abstract The paper presents an approach to sequence planning consisting in determining assembly sequences defined in terms of mating and non-mating operations and based on a dynamic expansion of the assembly tree obtained using a knowledge base management system. The planner considers the case of a single-robot assembly workcell. The use of stability and the detailed definition of sequences also by means of several non-mating operations are shown to be powerful instruments in the control of the tree expansion. Forward assembly planning has been chosen, in order to minimize the number of stability checks. Backtracking is avoided by combining precedence relations and stability analysis. Hard and soft constrains are introduced to drive the tree expansion. Hard constraints are precedence relations and stability analysis. All operations are associated to costs, which are used as soft constraints. The operation based approach enables one to manage even non-mating operations and to easily overcome the linearity constraint. Costs enable the planner to manage the association among tools and components. The first section of the paper concerns Stability Analysis that is subdivided into Static and Dynamic Stability Analysis. The former is mainly involved in analyzing gravity effects; the latter is mainly involved in evaluate inertia effects due to manipulation. Stability Analysis is implemented in a simplified form. Fundamental assumptions are: no rotational equilibrium condition is considered; for each reaction force only direction and versus, but not magnitude, are considered; friction is neglected. The second section discusses the structure of the planner and its implementation. The planner is a rule based system. Forward chaining and hypothetical reasoning are the inference strategies used. The knowledge base and the data base of the system are presented and the advantages obtained using a rule based system are discussed. The third section shows two planning examples, showing the performance of the system in a simple case and in an industrial test case, the assembly of a microwave branching filter composed of 26 components.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1007928631050
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  • 5
    Digitale Medien
    Digitale Medien
    Rapid isolation of muscle and heart mitochondria, the lability of oxidative phosphorylation and attempts to stabilize the process in vitro by taurine, carnitine and other compounds (1997)
    Springer
    Molecular and cellular biochemistry 174 (1997), S. 61-66 
    Details
    ISSN: 1573-4919
    Schlagwort(e): heart mitochondria ; lability ; muscle mitochondria ; oxidative phosphorylation ; stability ; taurine
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Chemie und Pharmazie , Medizin
    Notizen: Abstract We modified the isolation procedure of muscle and heart mitochondria. In human muscle, this resulted in a 3.4 fold higher yield of better coupled mitochondria in half the isolation time. In a preparation from rat muscle we studied factors that affected the stability of oxidative phosphorylation (oxphos) and found that it decreased by shaking the preparation on a Vortex machine, by exposure to light and by an increase in storage temperature. The decay was found to be different for each substrate tested. The oxidation of ascorbate was most stable and less sensitive to the treatments. When mitochondria were stored in the dark and the cold, the decrease in oxidative phosphorylation followed first order kinetics. In individual preparations of muscle and heart mitochondria, protection of oxidative phosphorylation was found by adding candidate stabilizers, such as desferrioxamine, lazaroids, taurine, carnitine, phosphocreatine, N-acetylcysteine, Trolox-C and ruthenium red, implying a role for reactive oxygen species and calcium-ions in the in vitro damage at low temperature to oxidative phosphorylation. In heart mitochondria oxphos with pyruvate and palmitoylcarnitine was most labile followed by glutamate, succinate and ascorbate.We studied the effect of taurine, hypotaurine, carnitine, and desferrioxamine on the decay of oxphos with these substrates. 1 mM taurine (n = 6) caused a significant protection of oxphos with pyruvate, glutamate and palmitoylcarnitine, but not with the other substrates. 5 mM L-carnitine (n = 6), 1 mM hypotaurine (n = 3) and 0.1 mM desferrioxamine (n = 3) did not protect oxphos with any of the substrates at a significant level. These experiments were undertaken in the hope that the in vitro stabilizers can be used in future treatment of patients with defects in oxidative phosphorylation. (Mol Cell Biochem 174: 61–66, 1997)
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1006803807814
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  • 6
    Digitale Medien
    Digitale Medien
    Calbindin D28k-like immunoreactivity in the developing and regenerating circumvallate papilla of the rat (1997)
    Springer
    Cell & tissue research 291 (1997), S. 81-90 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Key words Calbindin D28k ; Circumvallate papilla ; Taste buds ; Development ; Degeneration ; Regeneration ; Immunohistochemistry ; Rat (Sprague Dawley)
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract  The distribution of calbindin D28k (CB)-like immunoreactivity (-LI) in the circumvallate papilla (CVP) was examined during development and regeneration following bilateral crush injury to the glossopharyngeal nerve in the rat. In the adult CVP, CB-like immunoreactive (-IR) nerve fibers were observed in the subgemmal region and some penetrated into the taste buds. CB-LI was also detected in the cytoplasm of the spindle-shaped gustatory cells in the lower half of the trench epithelium, which contained numerous synaptic vesicles and bundles of intermediate filaments. These CB-IR gustatory cells made synapse-like contacts with CB-IR nerve terminals. Some CB-IR nerve terminals made contacts with the gustatory cells negative for CB-LI. At least three developmental stages were defined with regard to the developmental changes in the distribution of CB-LI: (1) Stage I (embryonic day (E) 18–postnatal day (P)5): CB-IR nerve fibers appeared in the lamina propria just beneath the newly-formed CVP at E18, but the gustatory epithelium of the CVP contained no CB-IR structures. Taste buds with taste pores appeared at P1. (2) Stage II (P5–10): thin CB-IR nerve fibers began entering the trench epithelium, but no CB-IR cells were observed. (3) Stage III (P10–adult): in addition to the intragemmal and perigemmal CB-IR nerve fibers, very few CB-IR cells appeared in the taste buds around P10, and their numbers increased progressively. The changes in the distribution of taste buds and CB-LI following glossopharyngeal nerve injury were similar to those observed during development. On post-operative day (PO) 4, the taste buds and CB-IR cells decreased markedly in number. These CB-IR cells became round in shape, and the number of CB-IR nerve fibers decreased markedly. On PO8, both taste buds and CB-IR cells disappeared completely. The regenerated taste buds were first observed on PO12, increased rapidly in number by PO20, and increased slowly thereafter. CB-IR nerve fibers accumulated at the subgemmal region and began penetrating into the trench wall epithelium around PO16. CB-IR cells appeared between PO20 and PO24, and their numbers increased progressively and reached the normal level on PO40. The topographical localizations of the taste buds and CB-IR cells during development and regeneration were comparable to those of normal animals. The delay of the time courses for appearance of CB-IR nerve fibers and CB-IR cells compared to the appearance of taste buds during development and regeneration suggests that CB in the gustatory epithelium may participate in the survival of the taste bud cells rather than in the induction of the taste buds.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s004410050981
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  • 7
    Digitale Medien
    Digitale Medien
    Anally projecting neurons exhibiting immunoreactivity to galanin, nitric oxide synthase and vasoactive intestinal peptide, detected by confocal laser scanning microscopy, in the intestine of the Atlantic cod, Gadus morhua (1997)
    Springer
    Cell & tissue research 287 (1997), S. 525-533 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Key words: Nervous system ; enteric ; Nitric oxide synthase ; Vasoactive intestinal peptide (VIP) ; Immunohistochemistry ; Myotomy ; Descending projections ; Gadus morhua (Teleostei)
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract. The projections of enteric neurons showing immunoreactivity for vasoactive intestinal peptide (VIP), nitric oxide synthase (NOS) and galanin were investigated in the myenteric plexus of the intestine of the Atlantic cod, Gadus morhua. Quantification of immunoreactive material on the proximal and distal side of a myotomy was performed by means of confocal laser scanning microscopy. NOS immunoreactivity was reduced anal to the myotomy, whereas there was an accumulation of immunoreactivity for VIP and for galanin oral to the cut. These results suggest the presence of VIP, NOS and galanin in neurons with oral–to–anal projections along the intestine of the cod. Since descending neurons in the myenteric plexus of many other vertebrates also contain these substances, we conclude that the oral–to–anal projections of neurons containing VIP, NOS and galanin are highly conserved features and important for the descending phase of intestinal peristalsis on an evolutionary basis.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s004410050776
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  • 8
    Digitale Medien
    Digitale Medien
    Multiple mechanisms contribute to myenteric plexus ablation induced by benzalkonium chloride in the guinea-pig ileum (1997)
    Springer
    Cell & tissue research 289 (1997), S. 253-264 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Key words: Myenteric plexus ; Benzalkonium chloride ; Immunohistochemistry ; Lymphocytes ; Macrophages ; Glia ; Oncoproteins ; Guinea pig (Rodentia)
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract. Ablation of rat myenteric plexus with benzalkonium chloride has provided a model of intestinal aganglionosis, but the degenerative responses are not well understood. We examined the effects of this detergent on neurons and glia, including expression of c-Myc, c-Jun, JunB, and c-Fos, and on immunocytes in the guinea-pig ileum. Benzalkonium chloride (0.1%) or saline was applied to the serosal surface of distal ileum. Tissues were analyzed 2, 3, or 7 days later and compared with cyclosporine-treated and untreated animals. More than 90% of myenteric neurons were destroyed in ileal segments 3–7 days after benzalkonium-chloride treatment. Glia withdrew processes from around neurons after 2 days and were mostly gone after 3 days. Neuronal c-Myc began to disappear while c-Fos, c-Jun, and JunB were evident in some neuronal nuclei after 2 or 3 days. After 3 days, widespread apoptosis was evident in the myenteric plexus. Populations of T cells, B cells, and macrophage-like cells in untreated and saline-treated myenteric plexuses were substantially increased 3 and 7 days after benzalkonium-chloride treatment. Cyclosporine delayed significant neuronal loss. We conclude that a variety of degenerative mechanisms may be active in this model, including an immune response which may actively contribute to tissue destruction.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s004410050872
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  • 9
    Digitale Medien
    Digitale Medien
    Distribution of neuropeptide Y-like immunoreactivity in the brain of the bichir, Polypterus senegalus, with special regard to the terminal nerve (1997)
    Springer
    Cell & tissue research 289 (1997), S. 275-284 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Key words: Neuropeptide Y ; Brain (CNS) ; vertebrate ; Terminal nerve ; FMRF amide ; Gonadotropin-releasing hormone ; Immunohistochemistry ; Polypterus senegalus (Polypteriformes)
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract. The distribution of neuropeptide Y (NPY)-like immunoreactivity in the brain of the bichir, Polypterus senegalus, was examined immunohistochemically. NPY-like immunoreactivity was distributed widely in the brain, with the highest density in the diencephalon. NPY-positive perikarya were found in various areas, including the terminal nerve, the pallial zones of the telencephalon, the periventricular preoptic nucleus, the thalamic nucleus, the ventral hypothalamus of the diencephalon, the tegmentum of the mesencephalon, and the area intermedioventralis of the rhombencephalon. In the hypothalamus, NPY-positive liquor-contacting neurons were frequently observed. Immunoreactive neuron-like cells also appeared in the distal lobe of the hypophysis. NPY fibers were densely distributed in the ventral telencephalon, the hypothalamus, and the ventrolateral area of the rhombencephalon. They were also demonstrated in the terminal nerve. In the hypophysis, NPY fibers were dense in the median eminence, but sparse in the neural lobe. Electron-microscopic double immunostaining of the terminal nerve revealed the coexistence of NPY-like antigen with gonadotropin-releasing hormone-like and molluscan cardioexcitatory tetrapeptide-like antigens in the same cytoplasmic granules. These results suggest that NPY or a related substance is involved in neuroregulation of various areas of the bichir brain, by mainly acting as a neurotransmitter or neuromodulator.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s004410050874
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  • 10
    Digitale Medien
    Digitale Medien
    FMRF amide-like-immunoreactive primary sensory neurons in the olfactory system of the terrestrial mollusc, Limax marginatus (1997)
    Springer
    Cell & tissue research 289 (1997), S. 339-345 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Key words: FMRF amide ; Immunohistochemistry ; Olfactory system ; Sensory neurons ; Neuromodulators ; Limax marginatus (Mollusca)
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract. The distribution of FMRF amide-like immunoreactivity was investigated in the olfactory organs in the tentacle tip of the terrestrial slug, Limax marginatus. Approximately 0.7% of the neurons in the lobules of the tentacle ganglia demonstrated FMRF amide-like immunoreactivity. Most of the FMRF amide-like-immunoreactive somata lay at superficial positions within the lobules, and dendritic processes extended to the outer surface of the sensory epithelium, whereas the axons traveled toward the cerebral ganglion through the ventral part of the tentacle nerve. From their morphological features, FMRF amide-like-immunoreactive cells were considered to be primary sensory neurons.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s004410050881
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  • 11
    Digitale Medien
    Digitale Medien
    Heterogeneous distribution of neurocalcin-immunoreactive nerve terminals in the mouse adrenal medulla (1997)
    Springer
    Cell & tissue research 289 (1997), S. 439-444 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Key words: Neurocalcin ; Calcium-binding protein ; Adrenal medulla ; Nerve terminal ; Immunohistochemistry ; Mouse (ddY)
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract. Neurocalcin is a novel calcium-binding protein found in bovine brain tissue. We investigated immunoreactivity for neurocalcin in the mouse adrenal medulla using light and electron microscopy. The immunoreactivity was present in nerve fibers, nerve terminals, and ganglion cells in the adrenal medulla, but chromaffin cells, sustentacular cells, and Schwann cells were negative in reaction. Nerve bundles containing neurocalcin-immunoreactive fibers passed through the adrenal cortex and extended into the medulla. Immunopositive nerve fibers branched off and projected varicose terminals around the chromaffin cells. These varicose terminals contained small and large-cored vesicles and made synapses with the chromaffin cells. We performed paraformaldehyde-induced fluorescence-histochemical studies for catecholamine combined with immunohistochemical studies for neurocalcin. Neurocalcin-immunoreactive nerve terminals were more abundant at noradrenaline (fluorescent) cell-rich regions than at adrenaline (non-fluorescent) cell-rich regions. These results show that neurocalcin-immunoreactive nerves mainly innervate noradrenaline-containing chromaffin cells in the mouse adrenal medulla and that neurocalcin may regulate synaptic function in the nerve terminals.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s004410050889
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  • 12
    Digitale Medien
    Digitale Medien
    Immunohistochemical and immuno-electron-microscopic detection of interferon-γ-inducing factor (”interleukin-18”) in mouse intestinal epithelial cells (1997)
    Springer
    Cell & tissue research 289 (1997), S. 499-503 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Key words: Interferon-γ-inducing factor (”interleukin-18”) ; Intestine ; Immunohistochemistry ; Mucosal immunity ; Mouse (CD1)
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract. The novel cytokine interferon-γ-inducing factor (”interleukin-18”) is produced by macrophage-like cells in mice with endotoxin shock and induces the production of interferon-γ by T cells in vitro. To determine the physiological role for mouse interferon-γ-inducing factor, we studied its tissue distribution in several organs (intestine, spleen, thymus, kidney, and liver) in healthy mice of different ages, including fetal stages. Activity of the cytokine in the organ extracts of adult mice was measured by enzyme-linked immunosorbent assay, and the cellular distribution of interferon-γ-inducing factor in organs from fetal and adult mice was determined by immunohistochemistry. Intestinal extracts of adult mice showed the highest concentrations among the organs studied. Other organ extracts of adult mice showed lower concentrations of the cytokine. Immunohistochemical analysis revealed that interferon-γ-inducing factor was localized in the cytoplasm of intestinal epithelial cells from fetal and adult mice. These results show for the first time that intestinal epithelial cells may be the main producers of interferon-γ-inducing factor under normal physiological conditions and suggest that its constitutive expression in intestinal epithelial cells may have an important role in the induction of mucosal immunity.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s004410050895
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  • 13
    Digitale Medien
    Digitale Medien
    Local disturbance of neuronal migration in the S-100β-retarded mutant mouse (1997)
    Springer
    Cell & tissue research 289 (1997), S. 547-551 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Key words: Bromodeoxyuridine (BrdU) ; Glial fibrillary acidic protein (GFAP) ; Immunohistochemistry ; Neuron-glia interaction ; Cortex ; Polydactyly mutant mouse (Pdn/Pdn; Pdn/+; +/+)
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract. Homozygotes of a mouse strain with genetic polydactyly (Pdn) show disrupted cortical lamination and a significant decrease of S-100β-immunoreactive elements in a particular area of the brain. In order to understand the abnormal cortical formation at the cellular level, the migration of cortical neurons and the development of glial cells were studied using bromodeoxyuridine (BrdU), S-100β, and glial fibrillary acidic protein (GFAP) immunohistochemistry. Homozygous mice (Pdn/Pdn) displayed a variable pattern of abnormalities. Irregular GFAP-positive radial glial cells and disturbance of neuronal migration were found in a circumscribed area of the caudo-dorsal cortex of newborn Pdn mouse. The number of S-100β-positive cells was reduced in this area. The present results suggest that abnormal cortical lamination closely correlates with disturbance of neuronal migration and abnormalities of glial cells, especially a significant decrease of S-100β-immunoreactive cells.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s004410050900
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  • 14
    Digitale Medien
    Digitale Medien
    Interstitial cells of Cajal in the guinea-pig gastrointestinal tract as revealed by c-Kit immunohistochemistry (1997)
    Springer
    Cell & tissue research 290 (1997), S. 11-20 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Key words: Interstitial cells of Cajal ; Gastrointestinal motility ; Enteric nervous system ; Smooth muscle ; Rhythmicity ; Immunohistochemistry ; Proto-oncogene ; Tyrosine kinase ; Guinea pig
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract. Interstitial cells of Cajal (ICC) of various morphologies have been described in the gastrointestinal (GI) tracts of mammals. Different classes of ICC are likely to have different functional roles. ICC of the mouse GI tract have been shown to express c-kit, a proto-oncogene that codes for a receptor tyrosine kinase. We have studied the distribution of ICC within the guinea pig GI tract using antibodies to c-Kit protein and immunohistochemical techniques. c-Kit-like immunoreactivity revealed at least 6 types of ICC: (1) intramuscular ICC (IC-IM1) that lie within the muscle layers of the esophagus, stomach, and cecum, (2) ICC within the myenteric plexus region (IC-MY1) in the corpus, antrum, small intestine, and colon,(3) ICC that populate the deep muscular plexus of the small intestine (IC-DMP), (4) ICC at the submucosal surface of the circular muscle layer in the colon (IC-SM), (5) stellate ICC that are closely associated with the myenteric plexus (IC-MY2) and orientated toward the longitudinal muscle layer in the colon, and (6) branching intramuscular ICC (IC-IM2) in the proximal colon within the circular and longitudinal muscle layers. c-Kit immunohistochemistry appears to be an excellent and selective technique for labeling ICC of the guinea-pig GI tract. Labeling of these cells at the light-microscopic level provides an opportunity for characterizing the distribution, density, organization, and relationship between ICC and other cell types.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s004410050902
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  • 15
    Digitale Medien
    Digitale Medien
    Remodeling of pineal epithelium in the fetal rat as delineated by immunohistochemistry of laminin and cadherin (1997)
    Springer
    Cell & tissue research 287 (1997), S. 263-274 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Key words: Pineal gland ; Laminin ; Cadherin ; Synaptophysin ; BrdU ; Immunohistochemistry ; Embryology ; Rat (Wistar)
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract. Epithelial remodeling in the rat pineal during fetal development was immunohistochemically analyzed by using antibodies for laminin and cadherin as molecular markers of basal lamina and intercellular junctions, respectively. The proliferation and differentiation of pinealocytes were also investigated in relation to the advance of epithelial remodeling. The pineal anlage of embryonic day 16 is completely covered by basal lamina immunolabeled for laminin. After embryonic day 17, local dissolution of the basal lamina occurs on the epithelial folds, which develop predominantly in the rostral pineal wall. Some pineal cells migrate through these interruptions and form cellular aggregations outside the basal lamina. Cadherin immunostaining reveals focal dissolution of intercellular junctions in epithelial regions protruding into the pineal lumen. Dissolution of the basal lamina and intercellular junctions accompanied by cellular migration into the stromal tissue or into the pineal lumen continues until birth. The distribution of mitotic cells immunolabeled for BrdU is homogeneous throughout the organ during the fetal period, whereas that of differentiating pinealocytes immunoreactive for synaptophysin shows striking regional heterogeneity in close correlation with the remodeling of the pineal epithelium. The migrating cell populations located either outside the basal lamina or inside the pineal lumen are more liable to become synaptophysin-positive than the rest of the epithelium. These results suggest that epithelial remodeling in the fetal pineal is induced, at least in part, by epithelial infolding and that this remodeling promotes the differentiation of pinealocytes.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s004410050751
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  • 16
    Digitale Medien
    Digitale Medien
    Distribution and subcellular localization of a lysosome-associated protein in human genital organs (1997)
    Springer
    Cell & tissue research 287 (1997), S. 335-342 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Key words: Lysosomal membrane antigen ; Immunohistochemistry ; Biosynthesis ; Prostate-membrane-specific antigen ; Apocrine secretion ; Human
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract. The tissue distribution, preferentially in the human male genital system, and the subcellular localization of the lysosome-associated membrane protein 2 (lamp 2) was studied immunohistochemically using a mouse monoclonal antibody, 2D5. Strong immunoreactivity was present in the tubular system of the kidney, in acinar cells of salivary glands and pancreas, prostate, mammary glands, placenta and in cutaneous sweat glands. Moderate immunoreactivity was observed in cerebral neuronal cells, epidermal cells, testis, epididymis, seminal vesicle and endometrium. Very low immunoreactivity was found in liver. In some of the tissues mentioned, the distribution pattern of immunoreactivity is smooth and homogeneous, while in others it is granular and concentrated in the supra- or perinuclear cytoplasm. The subcellular distribution was studied on ultracryosections and on pre-embedding-processed chopper sections of human prostate. In the latter gland, the protein is not restricted to epithelium, but is also present in stromal cells. Ultrastructurally, the immunoreactivity in secretory cells was localized in electron-translucent vacuoles and granules, including the secretory granules. A close association with cell membranes was not generally the case. Only part of the immunoreactive material was linked to the apical plasma membrane pointing to a biosynthesis independent from an association step with the apical plasma membrane. As shown by immunoelectron microscopy and Western blotting, a high amount of lamp 2 is secreted and is found in so-called prostasomes. The findings indicate that in the human prostate most of the membrane-bound lamp 2 is released from the secretory cells, presumably in an apocrine fashion.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s004410050758
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  • 17
    Digitale Medien
    Digitale Medien
    Cytokeratin-filament expression in epithelial and non-epithelial tissues of the common carp (Cyprinus carpio) (1997)
    Springer
    Cell & tissue research 287 (1997), S. 375-384 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Key words: Epithelia ; Intermediate filaments ; Cytokeratins ; Cytoskeleton ; Immunohistochemistry ; Mesenchyme ; Tissue fixation ; Cyprinus carpio (Teleostei)
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract. Cytokeratin expression in mammals is generally restricted to epithelial cells and has been utilized to differentiate epithelial from nonepithelial tissues in these species. Since cytokeratins have been shown to be highly conserved during vertebrate evolution, the objective of the present study has been to ascertain the expression pattern of cytokeratins in tissues of the common carp (Cyprinus carpio). A panel of 10 anti-human cytokeratin antibodies was evaluated using a streptavidin-biotin-peroxidase complex detection system. Tissues were fixed in 10% neutral-buffered formalin, 100% ethanol or methacarn. Only formalin-fixed tissues were pre-digested with trypsin prior to immunostaining. Formalin-fixed tissues generally resulted in a less intense, more diffuse staining pattern with considerable background compared with ethanol and methacarn and was therefore the least desirable fixative. The diverse staining pattern observed with the various antibodies used in this study was consistent with previous findings in other teleosts. The results confirm that cytokeratin expression in teleosts is fundamentally different from that in mammals and therefore should be used as a method to differentiate epithelial cell types in these species only with discretion.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s004410050763
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  • 18
    Digitale Medien
    Digitale Medien
    Transthyretin distribution in the developing choroid plexus of the South American opossum (Monodelphis domestica) (1997)
    Springer
    Cell & tissue research 287 (1997), S. 621-624 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Key words: Transthyretin ; Albumin ; Immunohistochemistry ; Development ; Choroid plexus ; Opossum ; Monodelphis domestica (Marsupialia)
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract. The distributions of transthyretin and albumin in the choroid plexus during brain development have been compared. The South American opossum was chosen because the young are born around the time of choroid plexus formation. Previous work showed that in the adult opossum, transthyretin is expressed in the choroid plexus cells. However, systematic studies of transthyretin in the choroid plexus during development have not been carried out before. Transthyretin was present in 90–95% of the choroidal cells from birth to adulthood. In most cells, transthyretin immunoreactivity was concentrated in the apical region of the cytoplasm. Double labelling of choroid plexus sections with antibodies to albumin and transthyretin showed that 1–2% of cells were positive for both proteins. These findings suggest that from the very earliest stage of choroid plexus formation most epithelial cells both synthesize and contain transthyretin, and a few of these transthyretin-synthesizing cells also contain albumin that is probably being transferred from blood to the cerebrospinal fluid.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s004410050785
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  • 19
    Digitale Medien
    Digitale Medien
    Exocytotic proteins in enterochromaffin-like (ECL) cells of the rat stomach (1997)
    Springer
    Cell & tissue research 290 (1997), S. 539-551 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Key words: Exocytotic proteins ; Synaptophysin ; Synaptotagmin ; Syntaxin ; Secretory granule ; Histidine decarboxylase (HDC) ; Immunohistochemistry ; Rat (Sprague Dawley)
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract. Proteins participating in vesicular docking and fusion have been identified in the nervous system. Such proteins appear to be important for the molecular regulation of exocytosis also in non-neuronal cells. The enterochromaffin-like (ECL) cells of the gastric acid-secreting (oxyntic) mucosa secrete histamine and chromogranin A-derived peptides, such as pancreastatin. Using immunohistochemistry, we have examined whether the ECL cells of the rat stomach, identified with antibodies to histidine decarboxylase (HDC, the histamine-forming enzyme), express the same exocytotic proteins as neurons. The ECL cells displayed immunoreactivity for synaptophysin, synaptotagmin III, vesicle-associated membrane protein-2 (VAMP-2), cysteine string protein (CSP), vesicular monoamine transporter-2 (VMAT-2), synaptosomal-associated protein of 25 kDa (SNAP-25), syntaxin, and Munc-18, but not for synaptotagmin I/II and VAMP-1. Synaptophysin and VMAT-2 could be detected not only in the ECL cells, but also in a population of HDC-negative cells. The demonstration of synaptotagmin III in only a limited number of ECL cells suggests the existence of a subpopulation of ECL cells. The results show that several exocytotic proteins, previously identified in neurons, are present in rat stomach ECL cells. Hence, proteins engaged in vesicular docking and in the fusion of granule/vesicle membrane with plasma membrane seem to exist in both neurons and endocrine cells.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s004410050960
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  • 20
    Digitale Medien
    Digitale Medien
    Distribution of vasotocin- and mesotocin-like immunoreactivities in the brain of Typhlonectes compressicauda (Amphibia, Gymnophiona): further assessment of primitive and derived traits of amphibian neuropeptidergic systems (1997)
    Springer
    Cell & tissue research 287 (1997), S. 305-314 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Key words: Central nervous system ; Vasotocin ; Mesotocin ; Comparative evolution ; Immunohistochemistry ; Typhlonectes compressicauda (Gymnophiona)
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract. To further assess primitive and derived conditions, we have studied the vasotocinergic (AVT) and mesotocinergic (MST) systems by immmunohistochemistry in the brain of Typhlonectes compressicauda. This species belongs to a separate order of amphibians which differs in several morphological and behavioral aspects from anurans and urodeles which have been studied previously. Nevertheless, the vasotocinergic and mesotocinergic systems of T. compressicauda are largely comparable to those of other amphibians. Apart from a well-developed hypothalamo-hypophysial system, extrahypothalamic AVT-and MST-immunoreactive groups of cells and extensive networks of fibers were found. A major difference, however, is that neuropeptidergic cells in the caudal hypothalamus and the midbrain tegmentum of T. compressicauda contain MST, whereas those in corresponding locations contain AVT in anurans and urodeles. This suggests that certain neuropeptidergic cell groups in the gymnophionan brain have switched from AVT to MST gene expression, and, thereby, offers a new view on the functional significance of these neuropeptidergic systems.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s004410050755
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  • 21
    Digitale Medien
    Digitale Medien
    Estimation of the duration of the cycle of the seminiferous epithelium in the non-human primate Macaca mulatta using the 5-bromodeoxyuridine technique (1997)
    Springer
    Cell & tissue research 288 (1997), S. 365-369 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Key words: Spermatogenesis ; Testis ; Cell cycle ; Immunohistochemistry ; Macaca mulatta (Primates)
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract. A comparatively low yield of germ cells has been reported for the spermatogenic process in primates. Kinetic studies of spermatogenesis and the spermatogenic cycle are needed to investigate this phenomenon but require the application of radioactively labeled compounds or irradiation. We have therefore investigated the suitability of a non-radioactive approach, viz., administration of 5-bromodeoxyuridine, for the determination of the kinetics of the spermatogenic cycle in a non-human primate, the rhesus monkey (Macaca mulatta). Four adult in-season animals received a bolus of 33 mg/kg 5-bromodeoxyuridine, one testis from each monkey was removed 3 h later and the other testis after 10 days and 11 h. Tissue was fixed in Bouin’s solution and embedded in Paraplast. 5-Bromodeoxyuridine was localized by immunogold-silver staining with a monoclonal antibody. PAS-hematoxylin counterstaining was used for spermatogenic stage identification. At 3 h, the leptotene and zygotene spermatocytes in stages VII–IX were the most advanced 5-bromodeoxyuridine-positive cells. At 10 days 11 h, the label had advanced and pachytene spermatocytes in stages VI–IX contained 5-bromodeoxyuridine. The duration of the spermatogenic cycle was 10.42±0.07 days (range: 10.25–10.62 days). Peritubular cells and interstitial cells were rarely 5-bromodeoxyuridine-positive, and Sertoli cells were consistently negative for 5-bromodeoxyuridine. Importantly, our kinetic data closely resemble those obtained by means of the application of irradiation for this macaque species. We conclude that administration of 5-bromodeoxyuridine represents a non-radioactive reliable approach for studying kinetic aspects of the spermatogenic process in primates.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s004410050822
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  • 22
    Digitale Medien
    Digitale Medien
    2-Acetylaminofluorene-produced selective cytotoxic damage of a ductal compartment and its repair in the submandibular gland of rats (1997)
    Springer
    Cell & tissue research 288 (1997), S. 371-379 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Key words: 2-Acetylaminofluorene ; Selective ductal cytotoxicity ; Submandibular gland ; Regenerative repair ; Immunohistochemistry ; Systemic effects ; Rat (Wistar)
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract. Salivary glands of rodents are rarely affected with spontaneous and induced malignancies. This may be linked with low physiologic cell renewal and the infrequency of cytolethal actions by xenobiotics. The genotoxic 2-acetylaminofluorene, carcinogenic for other organs, causes acute damage in salivary ducts. In the submandibular glands the damage is limited to the granulated convoluted tubules. They produce and release regulatory peptides including epidermal growth factor and nerve growth factor. The partial chemical sialoadenectomy is repaired by sequential cell proliferation in the basal cell layer of interlobular ducts and in dilated intralobular ducts (day 4 and 6), in intermediate duct-like structures (day 6 and 8), and lastly in acini (day 8 and 12). This is associated with a transient loss of structural characteristics of striated ducts and acini (up to day 6) and of the immunoreactivity for S-100 protein (up to day 4). Actin immunoreactivity at the acinar base is increased from day 6 to 20. Analogous to the late postnatal differentiation of the granulated convoluted tubules, their structural characteristics and immunoreactivity for epidermal growth factor do not recover within 20 days. The acute lesion of the endocrine ductal segment is suggested to be causally involved with other systemic effects following treatment with 2-acetylaminofluorene. First, hypophagia with loss of body, liver and thymus weight may result from disturbed saliva production. Second, previous studies have shown a mitotic burst of the biliary epithelium and bloodborne lymphocyte-stimulating activities. Either effect could be brought about by regulatory peptides (see above), probably after elevated circulatory release from necrotic granulated convoluted tubules.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s004410050823
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  • 23
    Digitale Medien
    Digitale Medien
    Expression of basic fibroblast growth factor-like immunoreactivity in the nuclei of regenerating hepatocytes (1997)
    Springer
    Cell & tissue research 288 (1997), S. 517-527 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Key words: Liver ; Subcellular fractions ; Immunohistochemistry ; Electron microscopy ; Rat (Wistar)
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract. This study, utilizing rats subjected to two-thirds partial hepatectomy or sham operation, was designed (1) to investigate the content of basic fibroblast growth factor (bFGF) in the subcellular fractions of regenerating and sham-operated rat livers by immunoblot experiments and enzyme-linked immunosorbent assay (ELISA), (2) to show that bFGF immunoreactivity and proliferating cell nuclear antigen (PCNA) immunoreactivity are markers for hepatocellular mitosis before and after partial hepatectomy, and (3) to observe the location and fine structure of the bFGF immunoreaction within the regenerating liver with special attention to bFGF immunoreactivity in the nuclei of regenerating hepatocytes. Immunoblot experiments and ELISA showed a transient increase in high-molecular-weight forms of bFGF in the nuclear subcellular fraction of regenerating liver 48 h after partial hepatectomy. By light microscopy, bFGF and PCNA immunoreactivities were detected in the nuclei of regenerating hepatocytes. Electron microscopy demonstrated bFGF-like immunoreactivity mainly in the nuclear euchromatin and rarely in the heterochromatin or nucleoli of regenerating hepatocytes. The transient increase in high-molecular-weight forms of bFGF in the nuclear euchromatin of regenerating hepatocytes, together with the concomitant expression of PCNA in the regenerating liver, suggests an important role of the high-molecular-weight forms of bFGF in hepatocyte proliferation and/or mitosis, although authentic bFGF with a molecular form of 18 kDa is not considered to be involved in hepatic regeneration.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s004410050837
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  • 24
    Digitale Medien
    Digitale Medien
    Evidence for the maintenance of macrophage-like cells in long-term bovine granulosa cell cultures (1997)
    Springer
    Cell & tissue research 288 (1997), S. 529-538 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Key words: Resident macrophages ; Follicle ; Ovary ; Cell culture ; Immunohistochemistry ; Cow
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract. Ovarian macrophages may be involved in the degradation of the basal membrane after rupture of a preovulatory follicle, or in angiogenesis during follicle and corpus luteum development, or may support steroidogenesis. The present study describes easy access to macrophage-like cells in the ovary and characterizes them. Cells from bovine antral follicles with 1–4 ml of their naturally occurring fluid were plated on day zero. On day 10, the granulosa cell culture showed macrophage-like cells. They developed as non-adherent cells and also adhered to the monolayer as single cells or as hemopoietic-like clones. The macrophage-like cells contained strong activity of non-specific esterase, acid phosphatase or 3β-hydroxy-steroid dehydrogenase (3β-HSD). Only the steroid enzyme was absent on day 19. As detected by immunolocalization, macrophage-like cells of various sizes showed a response for the CD18 surface molecule of leukocytes, for the CD45 molecule related to hemopoietic progenitor cells, and for the CD14 molecule selectively expressed on cells of the monocyte-macrophage lineage. The macrophage-like cells exhibited a granular-like actin structure as revealed by fluorochrome-labeled phalloidin. The ultrastructure of small, intermediate or large macrophage-like cells was similar to that of monocytes or of macrophages. In situ immunolabeling of intact or regressing follicles revealed single cells positive for CD14, CD18 or CD45. In order to establish that in vitro proliferation of the macrophage-like cells had occurred, their number was assessed between days 1 to 19 of cultivation. The cultures derived from 23 follicles were classified into groups A, B, or C according to the number of non-adherent cells (〈5000, 〈12 500, or ≥12 500 per 16-mm well) on day 12 of cultivation. The total number of macrophage-like cells (non-adherent and adherent) increased approximately fourfold in all groups between days 1 to 12. The total number decreased to day 5 levels between days 15 to 19. Thus, the macrophage-like cells probably represent a subpopulation of the macrophage family. They proliferate in co-culture with granulosa cells.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s004410050838
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  • 25
    Digitale Medien
    Digitale Medien
    Distribution of heat-shock protein 60 immunoreactivity in testes of infertile men (1997)
    Springer
    Cell & tissue research 288 (1997), S. 539-544 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Key words: Testis ; hsp60 ; Infertility ; Spermatogonia ; Immunohistochemistry ; Human
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract. The immunohistochemical localization of heat-shock protein 60 (hsp60) was investigated in testicular biopsies obtained from 121 adult men with disturbed fertility. In normal unaffected tubules, hsp60 immunoreactivity was localized to spermatogonia, primary spermatocytes and Sertoli cells. In spermatogonia, cytosolic and mitochondrial labelling could be differentiated. In general, the number of stained spermatogonia decreased with the loss of spermatogenic function. A significant (P〈0.01) reduction of stained spermatogonia was observed in testes with maturation arrest of spermatogenesis at the level of primary spermatocytes (30.2±21.6%) compared with testes exhibiting normal spermatogenesis. In addition, the decrease in the score correlated significantly with the diminution of cytosolic hsp60 immmunolabelling (coefficient r=0.25, P=0.03). There was a significant difference (P〈0.01) in the percentage of cytosolic-stained spermatogonia in testes with a score equal to or greater than 5 (14.7±9.8%) and a score less than 5 (8.9±6.9%). These observations suggest that a low level of hsp60 expression in spermatogonia may lead to a different pattern of protection, which in turn could be involved in low spermatogenic efficiency.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s004410050839
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  • 26
    Digitale Medien
    Digitale Medien
    Complement Cls, a classical enzyme with novel functions at the endochondral ossification center: immunohistochemical staining of activated Cls with a neoantigen-specific antibody (1997)
    Springer
    Cell & tissue research 288 (1997), S. 557-565 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Key words: Complement Cls ; Neoantigen ; Cartilage ; Hypertrophic chondrocyte ; Immunohistochemistry ; Rheumatoid arthritis ; Decorin ; Syrian hamster ; Human
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract. The secondary ossification center of 14- to 16-day-old hamster tibiae was examined immunohistochemically with active and inactive Cls-specific antibodies, RK5 and RK4, respectively. At the ossification center, chondrocytes differentiate from proliferating and hypertrophic to degenerating stages, and their site is occupied by the bone marrow. Cls was strongly immunostained in hypertrophic chondrocytes. In order to discover whether Cls is activated at a particular site, the cartilage was immunostained with RK5 and RK4. RK5 mainly reacted with degrading matrix around invading vessels. In contrast, RK4 strongly stained hypertrophic chondrocytes. Immunoelectron microscopy revealed Cls on degrading fragments of chondrocytes and fibers of cartilage matrix. Decorin, one of the major matrix proteoglycans, was dose and time dependently degraded by Cls. Type II collagen and type I gelatin were also degraded. Articular cartilage from patients with rheumatoid arthritis was positively immunostained (11/12 cases) with an anti-Cls monoclonal antibody (mAb) PG11, whereas normal articular cartilage (5/5 cases) was negative, suggesting Cls participation in the etiology of rheumatoid arthritis.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s004410050841
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  • 27
    Digitale Medien
    Digitale Medien
    Immunochemical demonstration of Eisenia tetradecapeptide, a bioactive peptide isolated from the gut of the earthworm Eisenia foetida, in tissues of the earthworm (1997)
    Springer
    Cell & tissue research 288 (1997), S. 567-573 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Key words: Eisenia tetradecapeptide ; Enzyme-linked immunosorbent assay (ELISA) ; Gut motility ; Immunohistochemistry ; Neuropeptide ; Peptide hormone ; Eisenia foetida (Annelida)
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract. The quantity and localization of Eisenia tetradecapeptide which was isolated from the gut of the earthworm Eisenia foetida were examined in tissues of the same species by enzyme-linked immunosorbent assay and immunohistochemistry. Analysis by enzyme-linked immunosorbent assay showed that Eisenia-tetradecapeptide-like immunoreactivity was present in both the central nervous system (cerebral ganglion, subesophageal ganglion, ventral ganglia, and ventral nerve cord) and the gut (esophagus, crop, gizzard, and intestine). The central nervous system contained a higher amount of Eisenia-tetradecapeptide-like immunoreactivity (1.3 pmol/mg wet weight) than the gut (0.2–0.6 pmol/mg wet weight). Eisenia-tetradecapeptide-like immunoreactivity was scarcely detected in the body-wall muscle, nephridia, and sexual organs (testis, ovary, seminal vesicle, and ovisac). Immunohistochemical analysis demonstrated that intense Eisenia-tetradecapeptide-like immunopositive cells and nerve fibers were present in the central nervous system. Immunoreactivity was found in the epithelial cells lining the esophagus and in the submucous plexus in various parts of the gut. Thus, the present study suggests that Eisenia tetradecapeptide is a neuropeptide and/or peptide hormone present in both the central nervous system and the gut of the earthworm and that its role involves the regulation of gut motility.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s004410050842
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  • 28
    Digitale Medien
    Digitale Medien
    Type II collagen and TGF-βs in developing and aging porcine mandibular condylar cartilage: immunohistochemical studies (1997)
    Springer
    Cell & tissue research 289 (1997), S. 119-124 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Key words: TGF-β ; Condylar cartilage ; Postnatal development ; Immunohistochemistry ; Pig
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract. Transforming growth factor-betas (TGF-βs) have been associated with the development and maintenance of articular cartilage. However, no studies have addressed their role in the postnatal development of mandibular condylar cartilage. This investigation represents the first immunohistochemical characterization of TGF-β isoforms and type II collagen in porcine mandibular condylar cartilage from various age groups. Furthermore, it is the first description of possible age-related changes in the expression of these proteins during postnatal development of this tissue. Condylar cartilage was dissected from freshly harvested temporomandibular joints of newborn, 6-, 12-, 24-, and 36-month-old farm swine. TGF-β1, TGF-β2, TGF-β3, and type II collagen were localized via standard immunohistochemical procedures. An immunoblot technique was employed to compare the relative amount of each protein present in the various age groups. Immunoreactivity was detected in mandibular condylar cartilage for all three isoforms of TGF-β and for Type II collagen. All age groups demonstrated some evidence of immunostaining, primarily in the cytoplasm of cells from most zones of the cartilage. Immunoblot results indicated that TGF-β isoforms had individualized patterns of expression. When newborn protein levels were taken as the baseline, TGF-β1 demonstrated a significant increase at ages 24 and 36 months. TGF-β2 significantly increased at 6, 12, 24, and 36 months (peak levels at 24 months; similar levels at 6, 12, and 36 months), whereas TGF-β3 remained stable at all ages. Type II collagen demonstrated increases that paralleled the increased levels of TGF-β1 and TGF-β2 at 24 and 36 months.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s004410050857
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  • 29
    Digitale Medien
    Digitale Medien
    Simultaneous restitution of matrix and cells in gastric ulcer: use of a combined in-situ hybridization and immunohistochemistry technique applicable to paraffin-embedded tissue (1997)
    Springer
    Cell & tissue research 287 (1997), S. 601-610 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Key words: Collagen ; Combined non-radioactive in-situ hybridization and immunohistochemistry ; Gastric ulcer ; Immunohistochemistry ; Rat (Wistar)
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract. The restoration of gastric tissue after ulceration involves cellular and matrix components. Our aim was to investigate the kinetics of collagen expression and cellular proliferation in an animal model of gastric ulcer. To demonstrate the expression of type I and IV collagen mRNAs by proliferating cells, a method combining in-situ hybridization and immunohistochemistry was devised. In order to avoid the disadvantages of radioisotopes, digoxigenin-labeled RNA-riboprobes were utilized and combined with single-step immunohistochemistry. This method proved sensitive enough to detect type I and IV procollagen mRNA transcripts in the submucosal area beneath the ulcer crater or adjacent to the ulcer rim. In addition, a subset of cells transcribing either procollagen type I or IV RNA was concomitantly positive for proliferating cell nuclear antigen by immunohistochemistry. Focal proliferation of cells simultaneously expressing extracellular matrix components may therefore occur in the gastric submucosa after ulceration, starting as soon as 3 days after the insult and continuing for several weeks. The devised method of combined in-situ hybridization and immunohistochemistry can be used with standard paraffin-embedded tissues, yields results within 2 days, and avoids radioisotopes.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s004410050783
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  • 30
    Digitale Medien
    Digitale Medien
    Neurochemical differentiation of rat enteric neurons during pre- and postnatal life (1997)
    Springer
    Cell & tissue research 288 (1997), S. 11-23 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Key words: Nitric oxide synthase (NOS) ; Vasoactive intestinal peptide (VIP) ; Pituitary-adenylyl-cyclase-activating peptide (PACAP) ; α-Internexin ; Peripherin ; Immunohistochemistry ; Rat (Wistar)
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract. The presence of nitric oxide synthase (the enzyme which synthesizes nitric oxide), vasoactive intestinal peptide (VIP) and pituitary adenylyl-cyclase-activating peptide (PACAP) in the rat enteric nervous system between term (E18) and 90 days postpartum (P90) was investigated by immunohistochemistry. Neuronal maturity was ascertained by emanining for the presence of two novel neuron intermediate filament proteins: α-internexin, which is transiently expressed in developing neurons, and peripherin, which is expressed in differentiating as well as in mature neurons. The alimentary canal of the foetus at E18, unfed newborn, suckling, weaning and adult rats was studied. Throughout the rat gut the myenteric neurons were recognized by the time the foetal stage was reached and the submucous neurons by the suckling period. α-Internexin was present at E18; its levels increased during ageing and were markedly reduced at P30. Peripherin was first detected at birth; its levels increased with ageing and pratically almost all of the neurons and nerve fibres were labelled from P30. Nitric oxide synthase was present at E18 and the number of labelled neurons gradually increased with ageing, while both VIP and PACAP could be detected by the end of the suckling period in an equal number of neurons to that in adulthood. These data indicate that in the rat gut the onset of the mature neuronal phenotype is not yet achieved at birth and that the neurochemical differentiation is accomplished during the first month of postnatal life.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s004410050788
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  • 31
    Digitale Medien
    Digitale Medien
    Distribution of neuropeptide-containing nerve fibers in the human submandibular gland, with special reference to the difference between serous and mucous acini (1997)
    Springer
    Cell & tissue research 288 (1997), S. 25-31 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Key words: Submandibular gland ; Neuropeptide Y ; Vasoactive intestinal polypeptide ; Galanin ; Substance P ; Calcitonin gene-related peptide ; Immunohistochemistry ; Human
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract. Distribution of neuropeptide Y (NPY)-, vasoactive intestinal polypeptide (VIP)-, galanin (GAL)-, substance P (SP)-, and calcitonin gene-related peptide (CGRP)-immunoreactive nerve fibers in the human submandibular gland was examined by the peroxidase-antiperoxidase method with attention to high-quality fixation and the condition of patients. NPY-, VIP-, and GAL-immunoreactive varicose fibers were densely distributed around the acini and ducts. Some of these fibers extended between acinar cells. The density of SP- and CGRP-immunoreactive fibers was relatively low. The number of NPY-, VIP-, and GAL-immunoreactive fibers around the mucous acini was significantly higher than around the serous acini. In the perivasculature, NPY-immunoreactive fibers were more numerous than other immunoreactive fibers. No somatostatin-, leucine-, or methionine-enkephalin-immunoreactive fibers were detected. Our findings suggest that a large number of periacinar VIP-, NPY-, and GAL-immunoreactive fibers may participate in regulating the synthesis of saliva and its secretion. Since the VIP-, NPY-, and GAL-immunoreactive fibers are more numerous around the mucous acini than around the serous ones, these fibers may take part more actively in regulating the secretory mechanisms in the mucous acini than in the serous ones. The relatively low number of CGRP- and SP-immunoreactive fibers suggests that they are less involved in the function of the human submandibular gland. Perivascular peptidergic fibers, especially NPY-immunoreactive fibers, may be involved in controlling local blood flow in this gland.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s004410050789
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  • 32
    Digitale Medien
    Digitale Medien
    Neuronal and nonneuronal taurine-like immunoreactivity in the sea pansy, Renilla koellikeri (Cnidaria, Anthozoa) (1997)
    Springer
    Cell & tissue research 288 (1997), S. 127-134 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Key words: Taurine ; Immunohistochemistry ; HPLC ; Amino acid neurotransmitters ; Renilla koellikeri (Cnidaria)
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract. A quantitative evaluation of putative amino acid neurotransmitters in sea pansy polyps by high-performance liquid chromatography indicates that the taurine content exceeds that of other amino acids by a 100-fold. The cellular source of this taurine was investigated by immunohistochemistry with two polyclonal antisera raised in rabbit, one against a glutaraldehyde-polylysine-taurine conjugate and the other against a succinylated ovalbumin-carbodiimide-taurine conjugate. Taurine-immunoreactive neurons were localized in a perioral subectodermal nerve net and in the zooid nerve net of the endodermal retractor muscle of the polyp mesenteries. Double labeling experiments revealed that taurine immunostaining does not colocalize with Phe–Mat–Ang–Phe –NH2 FMRFamide immunoreactivity. In addition, strong taurine immunoreactivity was found in nematocytes and other ectodermal cells, in myoepithelial cell bodies of the endoderm, and in calcareous spicule-producing cells of the colonial tissue mass. The limited distribution of neuronal taurine immunostaining to nerve nets associated with muscle systems subtending autozooid polyp retraction supports a role for taurine as a neuromuscular transmitter for this protective reflex. In contrast, the widespread distribution of taurine immunoreactivity in nematocytes and in other nonneuronal cells points to additional cellular functions of taurine, one of which may be to mediate responses to osmotic or metabolic stress.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s004410050800
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  • 33
    Digitale Medien
    Digitale Medien
    Transient expression of GAP-43 within the hippocampus after global brain ischemia in rat (1997)
    Springer
    Cell & tissue research 288 (1997), S. 225-238 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Key words: Cerebral ischemia ; Plasticity ; GAP-43 ; Hippocampus ; mRNA ; Immunohistochemistry ; Rat (Wistar)
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract. Neuroanatomical methods have been used to study selective vulnerability after global brain ischemia. A consistent pattern of ischemic neuronal damage is found in the rodent hippocampus with loss of CA1 neurons and of some cells in the hilus of the dentate gyrus. Very little is known about plastic changes that would be expected in ischemia-resistant areas such as CA3 neurons and granule cells. Neuronal plasticity after lesions may be indicated by changes in labeling with antibodies to the growth-associated protein 43 (GAP-43). Expression of GAP-43 as a marker for neuronal plasticity was studied here in the hippocampus after global brain ischemia. Halothane-anesthetized rats were subjected to 20 min of transient forebrain ischemia using four-vessel occlusion. In situ hybridization was used to study GAP-43 mRNA at 1, 3, 6, and 12 h and at 1, 3, and 7 days after ischemia. Immunostaining was carried out with two different antibodies to GAP-43 in brains which were perfusion-fixed after 1, 2, 4, and 7/8 days. In the control hippocampus, GAP-43 mRNA was localized to CA1–CA3 and the hilus. Moderate increases in cellular signals were seen in hilar cells and granule cells early after ischemia, and some changes occurred in CA3 at late stages. Hybridization was lost in CA1 due to cell death. With immunostaining, GAP-43 was not seen in the cytoplasm of neurons, whereas dense labeling occurred in a differentiated pattern in the axonal and dendritic layers. At 1 day after ischemia, neurons in the hilus of the dentate gyrus and in the stratum pyramidale and lucidum of CA3 showed strong cytoplasmic labeling for GAP-43. Few cells were labeled in these regions at 2 days, and none at later stages. Pyramidal cells in CA1 and CA3 areas and granule cells were never labeled. These studies demonstrate a transient expression of GAP-43 mRNA and protein in a subset of vulnerable neurons after transient brain ischemia. The cytoplasmic localization in hilar neurons could be due to increased synthesis of GAP-43 or to changes in axoplasmic transport. It is suggested that axonal damage occurs in hilar cells which stimulates GAP-43 expression. The increased production of trophic factors after ischemia in granule cells could also cause plastic changes in hilar cells. Since hilar neurons are in a strategic position to control the excitability of the dentate area, increased expression of GAP-43 may indicate an important pathophysiological process. In seizure experiments, strong expression of GAP-43 mRNA in granule cells was associated with abnormal mossy fiber sprouting and development of chronic epilepsy. The relevance of the minor GAP-43 mRNA upregulation after ischemia must be considered. The changes in CA3 neurons at several days after ischemia might represent a plastic response to a loss of CA1 neurons.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s004410050808
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  • 34
    Digitale Medien
    Digitale Medien
    Giant renin secretory granules in beige mouse renal afferent arterioles (1997)
    Springer
    Cell & tissue research 288 (1997), S. 399-406 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Key words: Kidney ; Renin ; Secretory granules ; Afferent arterioles ; Immunohistochemistry ; Mouse ; mutant beige (C57BL/6 bg) ; Mouse (NMRI)
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract. The mutant beige mouse (C57BL/6 bg) has a disease characterised by abnormally enlarged cytoplasmic granules in a variety of cells. With the purpose of establishing a suitable cellular model for studying renin secretion, the present study was undertaken to compare renin granule morphology in beige mice with that of control (NMRI) mice. Immunohistochemistry with an antibody specific for renin revealed intense staining of the juxtaglomerular part of the afferent arterioles in both strains of mice. Plasma renin concentrations were higher in the controls than in the beige mice (4.4±0.6 vs 2.5±0.3 mGoldblatt units/ml). The total volume of renin granules per afferent arteriole was similar in the two mice strains (1114 μm3 in the controls and 1507 μm3 in the beige mice). The total number of renin granules per arteriole as assessed by stereological techniques was about 1900 in controls (average granular volume 0.681 μm3), whereas 1–2 large granules were present per cell in beige mice. The volume of afferent arteriole that contained secretory granules was lower in the beige mice. We conclude that the beige mouse synthesizes, stores and releases active renin. Renin secretory granules in beige mice are grossly enlarged with 1–2 granules per juxtaglomerular cell. Compared with control mice, a similar amount of total renin granule volume per afferent arteriole is contained in a smaller part of beige mouse afferent arteriole. Granular cells from beige mice could therefore be a valuable tool in the study of renin release.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s004410050826
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  • 35
    Digitale Medien
    Digitale Medien
    Progressive stable interpolation (1997)
    Springer
    Numerical algorithms 14 (1997), S. 343-359 
    Details
    ISSN: 1572-9265
    Schlagwort(e): progressive interpolation ; stability ; spline ; shape parameters ; geometric continuity ; 41A05 ; 41A15 ; 65D05 ; 65D07
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Informatik , Mathematik
    Notizen: Abstract In this paper, we study several interpolating and smoothing methods for data which are known “progressively”. The algorithms proposed are governed by recurrence relations and our principal goal is to study their stability. A recurrence relation will be said stable if the spectral radius of the associated matrix is less than one. The iteration matrices depend on shape parameters which come either from the connection at the knots, or from the nature of the interpolant between two knots. We obtain various stability domains. Moving the parameters inside these domains leads to interesting shape effects.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1019129400864
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  • 36
    Digitale Medien
    Digitale Medien
    A New ADI Scheme for Solving Three-Dimensional Parabolic Differential Equations (1997)
    Springer
    Journal of scientific computing 12 (1997), S. 361-369 
    Details
    ISSN: 1573-7691
    Schlagwort(e): Alternating-direction implicit ; difference scheme ; stability ; convergence
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Informatik
    Notizen: Abstract A new alternating-direction implicit (ADI) scheme for solving three-dimensional parabolic differential equations has been developed based on the idea of regularized difference scheme. It is unconditionally stable and second-order accurate. Further, it overcomes the drawback of the Douglas scheme and is to be very well to simulate fast transient phenomena and to efficiently capture steady state solutions of parabolic differential equations. Numerical example is illustrated.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1025620828055
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  • 37
    Digitale Medien
    Digitale Medien
    Splitting Methods for Three-Dimensional Transport Models with Interaction Terms (1997)
    Springer
    Journal of scientific computing 12 (1997), S. 215-231 
    Details
    ISSN: 1573-7691
    Schlagwort(e): Transport models ; shallow water ; splitting methods ; stability
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Informatik
    Notizen: Abstract We investigate the use of splitting methods for the numerical integration of three-dimensional transport-chemistry models. In particular, we investigate various possibilities for the time discretization that can take advantage of the parallelization and vectorization facilities offered by multi-processor vector computers. To suppress wiggles in the numerical solution, we use third-order, upwind-biased discretization of the advection terms, resulting in a five-point coupling in each direction. As an alternative to the usual splitting functions, such as co-ordinate splitting or operator splitting, we consider a splitting function that is based on a three-coloured hopscotch-type splitting in the horizontal direction, whereas full coupling is retained in the vertical direction. Advantages of this splitting function are the easy application of domain decomposition techniques and unconditional stability in the vertical, which is an important property for transport in shallow water. The splitting method is obtained by combining the hopscotch-type splitting function with various second-order splitting formulae from the literature. Although some of the resulting methods are highly accurate, their stability behaviour (due to horizontal advection) is quite poor. Therefore we also discuss several new splitting formulae with the aim to improve the stability characteristics. It turns out that this is possible indeed, but the price to pay is a reduction of the accuracy. Therefore, such methods are to be preferred if accuracy is less crucial than stability; such a situation is frequently encountered in solving transport problems. As part of the project TRUST (Transport and Reactions Unified by Splitting Techniques), preliminary versions of the schemes are implemented on the Cray C98 4256 computer and are available for benchmarking.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1025645326705
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  • 38
    Digitale Medien
    Digitale Medien
    A Generalized Peaceman–Rachford ADI Scheme for Solving Two-Dimensional Parabolic Differential Equations (1997)
    Springer
    Journal of scientific computing 12 (1997), S. 353-360 
    Details
    ISSN: 1573-7691
    Schlagwort(e): Alternating-direction implicit ; difference scheme ; stability ; convergence
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Informatik
    Notizen: Abstract A generalized Peaceman–Rachford alternating-direction implicit (ADI) scheme for solving two-dimensional parabolic differential equations has been developed based on the idea of regularized difference scheme. It is to be very well to simulate fast transient phenomena and to efficiently capture steady state solutions of parabolic differential equations. Numerical example is illustrated.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1025631211217
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  • 39
    Digitale Medien
    Digitale Medien
    Stable, recombinant expression of human insulin-like growth factor binding protein-1 (hIGFBP-1) in Chinese hamster ovary (CHO) cells (1997)
    Springer
    Cytotechnology 24 (1997), S. 193-200 
    Details
    ISSN: 1573-0778
    Schlagwort(e): CHO cells ; DHFR ; IGFBP-1 ; stability
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin , Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Notizen: Abstract Stable expression of human insulin-like growth factor of binding protein-1 (hIGFBP-1)at high levels has been achieved in Chinese hamster ovary (CHO) cells by co-transfection and subsequent co-amplification of expression vectors containing the hIGFBP-1 cDNA and a dihydrofolate reductase (DHFR) cDNA gene into DHFR-deficient cells. Stepwise selection of the DHFR+ transformants in increasing concentrations of methotrexate (MTX) generated cells which had high copy numbers of the hIGFBP-1 gene (around 100 copies in cells amplified in medium containing 100 nM MTX). Expression of hIGFBP-1 in mixed clones was found to increase with increasing copy number and an apparent correlation between intra- and extracellular levels of hIGFBP-1 produced by these cells was observed. It was further observed that continuous cultivation over eight months in medium supplemented with 100 nM MTX increased the production of hIGFBP-1 25 times. The productivity did not increase further after five more months cultivation in MTX containing medium. A subcloning of this cell line gave clones with an even higher productivity. Further amplification in 500 nM or 1 uM MTX did not increase the hIGFBP-1 production.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1007999512662
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