ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Articles  (89,015)
  • Elsevier  (50,328)
  • Cell Press  (20,415)
  • BioMed Central  (12,428)
  • American Chemical Society  (5,732)
  • American Institute of Physics
  • American Meteorological Society
  • American Physical Society (APS)
  • MDPI Publishing
  • Reed Business Information
  • 2010-2014  (71,987)
  • 1995-1999
  • 1985-1989  (16,400)
  • 1955-1959  (628)
  • 1935-1939
  • 2012  (37,660)
  • 2010  (34,327)
  • 1989  (16,400)
  • 1955  (628)
  • Biology  (89,015)
Collection
  • Articles  (89,015)
Publisher
Years
  • 2010-2014  (71,987)
  • 1995-1999
  • 1985-1989  (16,400)
  • 1955-1959  (628)
  • 1935-1939
Year
  • 1
    Publication Date: 2012-10-24
    Electronic ISSN: 2161-5063
    Topics: Biology , Chemistry and Pharmacology
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
  • 3
    Publication Date: 2012-11-05
    Electronic ISSN: 2161-5063
    Topics: Biology , Chemistry and Pharmacology
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    Publication Date: 2012-11-01
    Electronic ISSN: 2161-5063
    Topics: Biology , Chemistry and Pharmacology
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    Publication Date: 2012-07-10
    Electronic ISSN: 2161-5063
    Topics: Biology , Chemistry and Pharmacology
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    Publication Date: 2012-06-06
    Electronic ISSN: 2161-5063
    Topics: Biology , Chemistry and Pharmacology
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    Publication Date: 2012-08-23
    Electronic ISSN: 2161-5063
    Topics: Biology , Chemistry and Pharmacology
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
  • 9
    Publication Date: 2012-06-13
    Electronic ISSN: 2161-5063
    Topics: Biology , Chemistry and Pharmacology
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    Publication Date: 2012-11-29
    Electronic ISSN: 2161-5063
    Topics: Biology , Chemistry and Pharmacology
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 11
    Publication Date: 2012-09-21
    Electronic ISSN: 2161-5063
    Topics: Biology , Chemistry and Pharmacology
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 12
    Publication Date: 2012-09-21
    Electronic ISSN: 2161-5063
    Topics: Biology , Chemistry and Pharmacology
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 13
    Publication Date: 2012-11-16
    Electronic ISSN: 2161-5063
    Topics: Biology , Chemistry and Pharmacology
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 14
    Publication Date: 2012-11-05
    Electronic ISSN: 2161-5063
    Topics: Biology , Chemistry and Pharmacology
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 15
    Publication Date: 2012-11-16
    Electronic ISSN: 2161-5063
    Topics: Biology , Chemistry and Pharmacology
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 16
    Publication Date: 2012-07-09
    Electronic ISSN: 2161-5063
    Topics: Biology , Chemistry and Pharmacology
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 17
    Publication Date: 2012-07-12
    Electronic ISSN: 2161-5063
    Topics: Biology , Chemistry and Pharmacology
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 18
    Publication Date: 2012-06-15
    Electronic ISSN: 2161-5063
    Topics: Biology , Chemistry and Pharmacology
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 19
    Publication Date: 2012-05-11
    Electronic ISSN: 2161-5063
    Topics: Biology , Chemistry and Pharmacology
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 20
  • 21
    Publication Date: 2012-03-13
    Electronic ISSN: 2161-5063
    Topics: Biology , Chemistry and Pharmacology
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 22
    Publication Date: 2012-10-17
    Electronic ISSN: 2161-5063
    Topics: Biology , Chemistry and Pharmacology
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 23
    Publication Date: 2012-11-14
    Electronic ISSN: 2161-5063
    Topics: Biology , Chemistry and Pharmacology
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 24
    Publication Date: 2012-11-16
    Electronic ISSN: 2161-5063
    Topics: Biology , Chemistry and Pharmacology
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 25
  • 26
    Publication Date: 2012-12-04
    Electronic ISSN: 2161-5063
    Topics: Biology , Chemistry and Pharmacology
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 27
    Publication Date: 2012-11-26
    Electronic ISSN: 2161-5063
    Topics: Biology , Chemistry and Pharmacology
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 28
    Publication Date: 2012-11-05
    Electronic ISSN: 2161-5063
    Topics: Biology , Chemistry and Pharmacology
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 29
    Publication Date: 2012-11-05
    Electronic ISSN: 2161-5063
    Topics: Biology , Chemistry and Pharmacology
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 30
    Publication Date: 2012-10-31
    Electronic ISSN: 2161-5063
    Topics: Biology , Chemistry and Pharmacology
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 31
    Publication Date: 2012-09-17
    Electronic ISSN: 2161-5063
    Topics: Biology , Chemistry and Pharmacology
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 32
    Publication Date: 2012-10-17
    Electronic ISSN: 2161-5063
    Topics: Biology , Chemistry and Pharmacology
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 33
    Publication Date: 2012-10-09
    Electronic ISSN: 2161-5063
    Topics: Biology , Chemistry and Pharmacology
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 34
    Publication Date: 2012-04-02
    Electronic ISSN: 2161-5063
    Topics: Biology , Chemistry and Pharmacology
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 35
  • 36
    Publication Date: 2012-05-04
    Electronic ISSN: 2161-5063
    Topics: Biology , Chemistry and Pharmacology
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 37
    Publication Date: 2012-02-11
    Description: Micro-relief heterogeneity can lead to substantial variability in microclimate and hence niche opportunities on a small scale. We explored the relationship between plant species richness and small-scale heterogeneity of micro-relief on the subtropical island of La Palma, Canary Islands. Overall, we sampled 40 plots in laurel and pine forests at four altitudinal bands. Species richness was recorded separately for various growth forms (i.e., mosses, herbaceous and woody plants). Site conditions such as altitude, slope, aspect, and tree density were measured. Micro-relief heterogeneity was characterized by surface structure and a subsequently derived surface heterogeneity index. The effect of micro-relief heterogeneity on species richness was analysed by means of linear mixed effect models and variance partitioning. Effects of micro-relief heterogeneity on species richness varied considerably between growth forms. While moss richness was affected significantly by micro-relief heterogeneity, herbaceous and woody plants richness responded mainly to larger-scale site conditions such as aspect and tree density. Our results stress the importance of small-scale relief heterogeneity for the explanation of spatial patterns of species richness. This poses new challenges as small-scale heterogeneity is largely underrepresented, e.g. with regard to its application in species distribution models.
    Electronic ISSN: 1424-2818
    Topics: Biology
    Published by MDPI Publishing
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 38
    Publication Date: 2012-12-28
    Description: 27 December 2012 Publication year: 2012 Source: Cell Reports, Volume 2, Issue 6 Insulin stimulates glucose uptake through the membrane translocation of GLUT4 and GLUT1. Peroxisome proliferator-activated receptor γ (PPARγ) enhances insulin sensitivity. Here, we demonstrate that insulin stimulates GLUT4 and GLUT1 translocation, and glucose uptake, by activating the signaling pathway involving nicotinic acid adenine dinucleotide phosphate (NAADP), a calcium mobilizer, in adipocytes. We also demonstrate that PPARγ mediates insulin sensitization by enhancing NAADP production through upregulation of CD38, the only enzyme identified for NAADP synthesis. Insulin produced NAADP by both CD38-dependent and -independent pathways, whereas PPARγ produced NAADP by CD38-dependent pathway. Blocking the NAADP signaling pathway abrogated both insulin-stimulated and PPARγ-induced GLUT4 and GLUT1 translocation, thereby inhibiting glucose uptake. CD38 knockout partially inhibited insulin-stimulated glucose uptake. However, CD38 knockout completely blocked PPARγ-induced glucose uptake in adipocytes and PPARγ-mediated amelioration of glucose tolerance in diabetic mice. These results demonstrated that the NAADP signaling pathway is a critical molecular target for PPARγ-mediated insulin sensitization. Graphical abstract Highlights ► Insulin induces glucose uptake via NAADP-mediated calcium increase ► PPARγ mediates insulin sensitization by upregulating the NAADP-producing enzyme CD38 ► PPARγ agonists ameliorate glucose tolerance by CD38 upregulation
    Electronic ISSN: 2211-1247
    Topics: Biology
    Published by Elsevier on behalf of Cell Press.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 39
    Publication Date: 2012-12-28
    Description: Available online 27 December 2012 Publication year: 2012 Source: Cell Reports Enveloped viruses have developed various adroit mechanisms to invade their host cells. This process requires one or more viral envelope glycoprotein to achieve cell attachment and membrane fusion. Members of the Flaviviridae such as flaviviruses possess only one envelope glycoprotein, E, whereas pestiviruses and hepacivirus encode two glycoproteins, E1 and E2. Although E2 is involved in cell attachment, it has been unclear which protein is responsible for membrane fusion. We report the crystal structures of the homodimeric glycoprotein E2 from the pestivirus bovine viral diarrhea virus 1 (BVDV1) at both neutral and low pH. Unexpectedly, BVDV1 E2 does not have a class II fusion protein fold, and at low pH the N-terminal domain is disordered, similarly to the intermediate postfusion state of E2 from sindbis virus, an alphavirus. Our results suggest that the pestivirus and possibly the hepacivirus fusion machinery are unlike any previously observed. Graphical abstract Highlights ► Structure of the major antigenically dominant protein of BVDV ► The overall fold of BVDV E2 shows no similarity to the class II fusion proteins ► At low pH, BVDV E2 N-terminal domain is disordered ► Entry mechanism of BVDV is probably applicable to hepatitis C virus
    Electronic ISSN: 2211-1247
    Topics: Biology
    Published by Elsevier on behalf of Cell Press.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 40
    Publication Date: 2012-12-28
    Description: Background: Trypanosoma cruzi, the causal agent of Chagas Disease, affects more than 16 million people in Latin America. The clinical outcome of the disease results from a complex interplay between environmental factors and the genetic background of both the human host and the parasite. However, knowledge of the genetic diversity of the parasite, is currently limited to a number of highly studied loci. The availability of a number of genomes from different evolutionary lineages of T. cruzi provides an unprecedented opportunity to look at the genetic diversity of the parasite at a genomic scale. Results: Using a bioinformatic strategy, we have clustered T. cruzi sequence data available in the public domain and obtained multiple sequence alignments in which one or two alleles from the reference CL-Brener were included. These data covers 4 major evolutionary lineages (DTUs): TcI, TcII, TcIII, and the hybrid TcVI. Using these set of alignments we have identified 288,957 high quality single nucleotide polymorphisms and 1,480 indels. In a reduced re-sequencing study we were able to validate ~ 97% of high-quality SNPs identified in 47 loci. Analysis of how these changes affect encoded protein products showed a 0.77 ratio of synonymous to non-synonymous changes in the T. cruzi genome. We observed 113 changes that introduce or remove a stop codon, some causing significant functional changes, and a number of tri-allelic and tetra-allelic SNPs that could be exploited in strain typing assays. Based on an analysis of the observed nucleotide diversity we show that the T. cruzi genome contains a core set of genes that are under apparent purifying selection. Interestingly, orthologs of known druggable targets show statistically significant lower nucleotide diversity values. Conclusions: This study provides the first look at the genetic diversity of T. cruzi at a genomic scale. The analysis covers an estimated ~ 60% of the genetic diversity present in the population, providing an essential resource for future studies on the development of new drugs and diagnostics, for Chagas Disease. These data is available through the TcSNP database (http://snps.tcruzi.org).
    Electronic ISSN: 1471-2164
    Topics: Biology
    Published by BioMed Central
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 41
    Publication Date: 2012-12-28
    Description: Background: MicroRNAs (miRNAs) are a class of small non-coding RNAs that regulate gene expression by targeting mRNAs for translation repression or mRNA degradation. Although many miRNAs have been discovered and studied in human and mouse, few studies focused on porcine miRNAs, especially in genome wide. Results: Here, we adopted computational approaches including support vector machine (SVM) and homology searching to make a global scanning on the pre-miRNAs of pigs. In our study, we built the SVM-based porcine pre-miRNAs classifier with a sensitivity of 100%, a specificity of 91.2% and a total prediction accuracy of 95.6%, respectively. Moreover, 2204 novel porcine pre-miRNA candidates were found by using SVM-based pre-miRNAs classifier. Besides, 116 porcine pre-miRNA candidates were detected by homology searching. Conclusions: We identified the porcine pre-miRNA in genome-wide through computational approaches by utilizing the data sets of pigs and set up the porcine pre-miRNAs library which may provide us a global scanning on the pre-miRNAs of pigs in genome level and would benefit subsequent experimental research on porcine miRNA functional and expression analysis.
    Electronic ISSN: 1471-2164
    Topics: Biology
    Published by BioMed Central
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 42
    Publication Date: 2012-12-28
    Description: Background: Rhizobium tropici CIAT 899 and Rhizobium sp. PRF 81 are alpha-Proteobacteria that establish nitrogen-fixing symbioses with a range of legume hosts. These strains are broadly used in commercial inoculants for application to common bean (Phaseolus vulgaris) in South America and Africa. Both strains display intrinsic resistance to several abiotic stressful conditions such as low soil pH and high temperatures, which are common in tropical environments, and to several antimicrobials, including pesticides. The genetic determinants of these interesting characteristics remain largely unknown. Results: Genome sequencing revealed that CIAT 899 and PRF 81 share a highly-conserved symbiotic plasmid (pSym) that is present also in Rhizobium leucaenae CFN 299, a rhizobium displaying a similar host range. This pSym seems to have arisen by a co-integration event between two replicons. Remarkably, three distinct nodA genes were found in the pSym, a characteristic that may contribute to the broad host range of these rhizobia. Genes for biosynthesis and modulation of plant-hormone levels were also identified in the pSym. Analysis of genes involved in stress response showed that CIAT 899 and PRF 81 are well equipped to cope with low pH, high temperatures and also with oxidative and osmotic stresses. Interestingly, the genomes of CIAT 899 and PRF 81 had large numbers of genes encoding drug-efflux systems, which may explain their high resistance to antimicrobials. Genome analysis also revealed a wide array of traits that may allow these strains to be successful rhizosphere colonizers, including surface polysaccharides, uptake transporters and catabolic enzymes for nutrients, diverse iron-acquisition systems, cell wall-degrading enzymes, type I and IV pili, and novel T1SS and T5SS secreted adhesins. Conclusions: Availability of the complete genome sequences of CIAT 899 and PRF 81 may be exploited in further efforts to understand the interaction of tropical rhizobia with common bean and other legume hosts.
    Electronic ISSN: 1471-2164
    Topics: Biology
    Published by BioMed Central
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 43
    Publication Date: 2012-12-28
    Description: Background: The objective of the research was to evaluate the current effectiveness of Ciprofloxacin on the uropathogens prevalent in infected urines of a cross-section of patients in Karachi, Pakistan.FindingsAn observational study conducted in a private diagnostic laboratory and its branches in key areas of Karachi City from February 2010 to July 2011. A total of 2963 consecutive urine samples were cultured on chocolate agar, CLED medium and selective EMB agar. Growth of possible uropathogens was noted, and compared retrospectively with earlier lab data of suggestive urine cultures (n = 1997) recorded during January 2009 and December 2009. The isolates were identified using routine procedures and the API 20 system and evaluated for their sensitivity to ciprofloxacin by Kirby-Bauer disk diffusion method. Data was subjected to statistical analysis on SPSS version 16. Out of the present-day culture-positive urines, 2409 (80.4%) yielded gram-negative rods, and 554 (18.5%) gram-positive cocci. E.coli (43.1%) was most frequent, followed by Klebsiella pneumoniae (22.4%) and Staphylococcus aureus (15.5%). 57.2% of the Gram-negative bacteria and 48.7% of the Gram-positive isolates were resistant to ciprofloxacin. In the earlier (2009) screening, 39% of Gram-negative rods and 48% of Gram-positive cocci were indifferent to the drug. Conclusions: A decrease in bacterial susceptibility of uropathogens to ciprofloxacin, a commonly prescribed drug in our population, is underlined, occurring possibly due to overuse pressure. Empirical initial treatment with ciprofloxacin would be inadequate in more than half of UTI cases, thereby counseling increased C/S testing of urines to provide existing sensitivity data for apt drug prescription.
    Electronic ISSN: 1756-0500
    Topics: Biology , Medicine
    Published by BioMed Central
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 44
    Publication Date: 2012-12-28
    Description: Background: Data accuracy and completeness are crucial for ensuring both the correctness and epidemiological relevance of a given data set. In this study we evaluated a clinical register in the administrative district of Marburg-Biedenkopf, Germany, for these criteria. Methods: The register contained data gathered from a comprehensive integrated breast-cancer network from three hospitals that treated all included incident cases of malignant breast cancer in two distinct time periods from 1996--97 (N=389) and 2003--04 (N=488). To assess the accuracy of this data, we compared distributions of risk, prognostic, and predictive factors with distributions from established secondary databases to detect any deviations from these [prime][prime]true[prime][prime] population parameters. To evaluate data completeness, we calculated epidemiological standard measures as well as incidence-mortality-ratios (IMRs). Results: In total, 12% (13 of 109) of the variables exhibited inaccuracies: 9% (5 out of 56) in 1996--97 and 15% (8 out of 53) in 2003--04. In contrast to raw, unstandardized incidence rates, (in-) directly age-standardized incidence rates showed no systematic deviations. Our final completeness estimates were IMR=36% (1996--97) and IMR=43% (2003--04). Conclusion: Overall, the register contained accurate, complete, and correct data. Regional differences accounted for detected inaccuracies. Demographic shifts occurred. Age-standardized measures indicate an acceptable degree of completeness. The IMR method of measuring completeness was inappropriate for incidence-based data registers. For the rising number of population-based health-care networks, further methodological advancements are necessary. Correct and epidemiologically relevant data are crucial for clinical and health-policy decision-making.
    Electronic ISSN: 1756-0500
    Topics: Biology , Medicine
    Published by BioMed Central
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 45
    Publication Date: 2012-12-28
    Description: Background: Patients increasingly turn to the Internet for information on medical conditions, including clinical news and treatment options. In recent years, an online patient community has arisen alongside the rapidly expanding world of social media, or "Web 2.0." Twitter provides real-time dissemination of news, information, personal accounts and other details via a highly interactive form of social media, and has become an important online tool for patients. This medium is now considered to play an important role in the modern social community of online, "wired" cancer patients. Results: Fifty-one highly influential "power accounts" belonging to cancer patients were extracted from a dataset of 731 Twitter accounts with cancer terminology in their profiles. In accordance with previously established methodology, "power accounts" were defined as those Twitter accounts with 500 or more followers. We extracted data on the cancer patient (female) with the most followers to study the specific relationships that existed between the user and her followers, and found that the majority of the examined tweets focused on greetings, treatment discussions, and other instances of psychological support. These findings went against our hypothesis that cancer patients' tweets would be centered on the dissemination of medical information and similar "newsy" details. Conclusions: At present, there exists a rapidly evolving network of cancer patients engaged in information exchange via Twitter. This network is valuable in the sharing of psychological support among the cancer community.
    Electronic ISSN: 1756-0500
    Topics: Biology , Medicine
    Published by BioMed Central
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 46
    facet.materialart.
    Unknown
    Elsevier
    Publication Date: 2012-12-28
    Description: 27 December 2012 Publication year: 2012 Source: Cell Reports, Volume 2, Issue 6 Controversy has recently arisen over the role of sirtuins in metazoan aging. In this issue of Cell Reports , Banerjee et al. demonstrate that Drosophila Sir2 is necessary for life span extension in response to dietary restriction and that its overexpression in the fat body increases the life span.
    Electronic ISSN: 2211-1247
    Topics: Biology
    Published by Elsevier on behalf of Cell Press.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 47
    Publication Date: 2012-12-28
    Description: 27 December 2012 Publication year: 2012 Source: Cell Reports, Volume 2, Issue 6 Inhibition of sirtuin 2 (SIRT2) deacetylase mediates protective effects in cell and invertebrate models of Parkinson’s disease and Huntington’s disease (HD). Here we report the in vivo efficacy of a brain-permeable SIRT2 inhibitor in two genetic mouse models of HD. Compound treatment resulted in improved motor function, extended survival, and reduced brain atrophy and is associated with marked reduction of aggregated mutant huntingtin, a hallmark of HD pathology. Our results provide preclinical validation of SIRT2 inhibition as a potential therapeutic target for HD and support the further development of SIRT2 inhibitors for testing in humans. Graphical abstract Highlights ► Sirtuin 2 (SIRT2) inhibition is neuroprotective in two HD mouse models ► SIRT2 inhibitor treatment markedly reduces huntingtin aggregates in HD mouse brain ► SIRT2 is a promising therapeutic target for neurological protein aggregation disorders
    Electronic ISSN: 2211-1247
    Topics: Biology
    Published by Elsevier on behalf of Cell Press.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 48
    Publication Date: 2012-12-28
    Description: Background: Exposure to early adverse events can result in the development of later psychopathology, and is often associated with cognitive impairment. This may be due to accelerated cell aging, which can be catalogued by attritioned telomeres. Exercise enhances neurogenesis and has been proposed to buffer the effect of psychological stress on telomere length. This study aimed to investigate the impact of early developmental stress and voluntary exercise on telomere length in the ventral hippocampus (VH) and prefrontal cortex (PFC) of the rat. Forty-five male Sprague--Dawley rats were categorised into four groups: maternally separated runners (MSR), maternally separated non-runners (MSnR), non-maternally separated runners (nMSR) and non-maternally separated non-runners (nMSnR). Behavioural analyses were conducted to assess anxiety-like behaviour and memory performance in the rats, after which relative telomere length was measured using qPCR. Results: Maternally separated (MS) rats exhibited no significant differences in either anxiety levels or memory performance on the elevated-plus maze and the open field compared to non-maternally separated rats at 49 days of age. Exercised rats displayed increased levels of anxiety on the day that they were removed from the cages with attached running wheels, as well as improved spatial learning and temporal recognition memory compared to non-exercised rats. Exploratory post-hoc analyses revealed that maternally separated non-exercised rats exhibited significantly longer telomere length in the VH compared to those who were not maternally separated; however, exercise appeared to cancel this effect since there was no difference in VH telomere length between maternally separated and non-maternally separated runners. Conclusions: The increased telomere length in the VH of maternally separated non-exercised rats may be indicative of reduced cellular proliferation, which could, in turn, indicate hippocampal dysfunction. This effect on telomere length was not observed in exercised rats, indicating that voluntary exercise may buffer against the progressive changes in telomere length caused by alterations in maternal care early in life. In future, larger sample sizes will be needed to validate results obtained in the present study and obtain a more accurate representation of the effect that psychological stress and voluntary exercise have on telomere length.
    Electronic ISSN: 1756-0500
    Topics: Biology , Medicine
    Published by BioMed Central
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 49
    Publication Date: 2012-12-28
    Description: 27 December 2012 Publication year: 2012 Source: Cell Reports, Volume 2, Issue 6 Planar cell polarity (PCP) refers to the collective orientation of cells within the epithelial plane. We show that progenitor cells forming the ducts of the embryonic pancreas express PCP proteins and exhibit an active PCP pathway. Planar polarity proteins are acquired at embryonic day 11.5 synchronously to apicobasal polarization of pancreas progenitors. Loss of function of the two PCP core components Celsr2 and Celsr3 shows that they control the differentiation of endocrine cells from polarized progenitors, with a prevalent effect on insulin-producing beta cells. This results in a decreased glucose clearance. Loss of Celsr2 and 3 leads to a reduction of Jun phosphorylation in progenitors, which, in turn, reduces beta cell differentiation from endocrine progenitors. These results highlight the importance of the PCP pathway in cell differentiation in vertebrates. In addition, they reveal that tridimensional organization and collective communication of cells are needed in the pancreatic epithelium in order to generate appropriate numbers of endocrine cells. Graphical abstract Highlights ► PCP proteins are restricted to progenitor cells in the embryonic pancreas ► The PCP core components Celsr2 and Celsr3 control endocrine cell differentiation ► This effect is mediated by the JNK pathway
    Electronic ISSN: 2211-1247
    Topics: Biology
    Published by Elsevier on behalf of Cell Press.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 50
    Publication Date: 2012-12-28
    Description: Background: Graph-based modularity analysis has emerged as an important tool to study the functional organization of biological networks. However, few methods are available to study state-dependent changes in network modularity using biological activity data. We develop a weighting scheme, based on metabolic flux data, to adjust the interaction distances in a reaction-centric graph model of a metabolic network. The weighting scheme was combined with a hierarchical module assignment algorithm featuring the preservation of metabolic cycles to examine the effects of cellular differentiation and enzyme inhibitions on the functional organization of adipocyte metabolism. Results: Our analysis found that the differences between various metabolic states primarily involved the assignment of two specific reactions in fatty acid synthesis and glycerogenesis. Our analysis also identified cyclical interactions between reactions that are robust with respect to metabolic state, suggesting possible co-regulation. Comparisons based on cyclical interaction distances between reaction pairs suggest that the modular organization of adipocyte metabolism is stable with respect to the inhibition of an enzyme, whereas a major physiological change such as cellular differentiation leads to a more substantial reorganization. Conclusion: Taken together, our results support the notion that network modularity is influenced by both the connectivity of the network's components as well as the relative engagements of the connections.
    Electronic ISSN: 1752-0509
    Topics: Biology
    Published by BioMed Central
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 51
    Publication Date: 2012-12-28
    Description: 27 December 2012 Publication year: 2012 Source: Cell Reports, Volume 2, Issue 6 MicroRNAs (miRNAs) are small, noncoding RNAs that inhibit translation and promote mRNA decay. The levels of mature miRNAs are the result of different rates of transcription, processing, and turnover. The noncanonical polymerase Gld2 has been implicated in the stabilization of miR-122, possibly through catalyzing 3′ monoadenylation; however, there is little evidence that this relationship is one of cause and effect. Here, we biochemically characterize Gld2’s involvement in miRNA monoadenylation and its effect on miRNA stability. We find that Gld2 directly monoadenylates and stabilizes specific miRNA populations in human fibroblasts and that sensitivity to monoadenylation-induced stability depends on nucleotides in the miRNA 3′ end. These results establish a mechanism of miRNA stability and resulting posttranscriptional gene regulation. Graphical abstract Highlights ► Gld2 monoadenylates specific microRNAs (miRNAs) ► Monoadenylation stabilizes miRNA subpopulations and prolongs their activity ► Sensitivity to monoadenylation and stability depends on nucleotides in the miRNA 3′ end
    Electronic ISSN: 2211-1247
    Topics: Biology
    Published by Elsevier on behalf of Cell Press.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 52
    Publication Date: 2012-12-28
    Description: 27 December 2012 Publication year: 2012 Source: Cell Reports, Volume 2, Issue 6 In the cytoplasm, the correct delivery of membrane proteins is an essential and highly regulated process. The posttranslational targeting of the important tail-anchor membrane (TA) proteins has recently been under intense investigation. A specialized pathway, called the guided entry of TA proteins (GET) pathway in yeast and the transmembrane domain recognition complex (TRC) pathway in vertebrates, recognizes endoplasmic-reticulum-targeted TA proteins and delivers them through a complex series of handoffs. An early step is the formation of a complex between Sgt2/SGTA, a cochaperone with a presumed ubiquitin-like-binding domain (UBD), and Get5/UBL4A, a ubiquitin-like domain (UBL)-containing protein. We structurally characterize this UBD/UBL interaction for both yeast and human proteins. This characterization is supported by biophysical studies that demonstrate that complex formation is mediated by electrostatics, generating an interface that has high-affinity with rapid kinetics. In total, this work provides a refined model of the interplay of Sgt2 homologs in TA targeting. Graphical abstract Highlights ► Sgt2 homologs contain dimerization motifs that are novel UBDs ► The UBL of Get5 homologs has features that distinguish it from other UBLs ► Complex formation of Sgt2 and Get5 includes a conserved and dynamic interface ► The system can rapidly discriminate between other UBL pathways
    Electronic ISSN: 2211-1247
    Topics: Biology
    Published by Elsevier on behalf of Cell Press.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 53
    Publication Date: 2012-12-28
    Description: 27 December 2012 Publication year: 2012 Source: Cell Reports, Volume 2, Issue 6 Chimera formation after blastocyst injection or morula aggregation is the principal functional assay of the developmental potential of mouse embryonic stem cells (ESCs). This property, which demonstrates functional equivalence between ESCs and the preimplantation epiblast, is not shared by epiblast stem cell (EpiSC) lines. Here, we show that EpiSCs derived either from postimplantation embryos or from ESCs in vitro readily generate chimeras when grafted to postimplantation embryos in whole embryo culture. EpiSC derivatives integrate and differentiate to derivatives of all three embryonic germ layers and primordial germ cells. In contrast, grafted ESCs seldom proliferate in postimplantation embryos, and fail to acquire the identity of their host-derived neighbors. EpiSCs do not incorporate efficiently into embryonic day 8.5 embryos, a stage by which pluripotency has been lost. Thus, chimera formation by EpiSCs requires a permissive environment, the postimplantation epiblast, and demonstrates functional equivalence between this cell type and EpiSCs. Graphical abstract Highlights ► Epiblast stem cells (EpiSCs) form chimeras when injected into postimplantation epiblast ► Embryonic stem cells do not form postimplantation chimeras ► EpiSCs do not integrate if they are injected after gastrulation
    Electronic ISSN: 2211-1247
    Topics: Biology
    Published by Elsevier on behalf of Cell Press.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 54
    Publication Date: 2012-12-28
    Description: 27 December 2012 Publication year: 2012 Source: Cell Reports, Volume 2, Issue 6 An increased understanding of antitumor immunity is necessary for improving cell-based immunotherapies against human cancers. Here, we investigated the roles of two immune system-expressed microRNAs (miRNAs), miR-155 and miR-146a, in the regulation of antitumor immune responses. Our results indicate that miR-155 promotes and miR-146a inhibits interferon γ (IFNγ) responses by T cells and reduces solid tumor growth in vivo. Using a double-knockout (DKO) mouse strain deficient in both miR-155 and miR-146a, we have also identified an epistatic relationship between these two miRNAs. DKO mice had defective T cell responses and tumor growth phenotypes similar to miR-155 −/− mice. Further analysis of the T cell compartment revealed that miR-155 modulates IFNγ expression through a mechanism involving repression of Ship1. Our work reveals critical roles for miRNAs in the reciprocal regulation of CD4 + and CD8 + T cell-mediated antitumor immunity and demonstrates the dominant nature of miR-155 during its promotion of immune responses. Graphical abstract Highlights ► miR-155 promotes and miR-146a inhibits both CD4+ and CD8+ T cell antitumor responses ► DKO mice reveal epistasis between miR-155 and miR-146a during tumor immunity ► miR-155 regulation of IFNγ involves repression of its target Ship1 in T cells
    Electronic ISSN: 2211-1247
    Topics: Biology
    Published by Elsevier on behalf of Cell Press.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 55
    Publication Date: 2012-12-28
    Description: Background: A novel herbal formulation LI10903F, alternatively known as LOWAT was developed based on its ability to inhibit adipogenesis and lipogenesis in 3T3-L1 adipocytes model. The clinical efficacy and tolerability of LI10903F were evaluated in an eight-week, randomized, double-blind, placebo-controlled, clinical trial in 50 human subjects with body mass index (BMI) between 30 and 40 kg/m2 (clinical trial registration number: ISRCTN37381706). Participants were randomly assigned to either a placebo or LI10903F group. Subjects in the LI10903F group received 300 mg of herbal formulation thrice daily, while subjects in the placebo group received 300 mg of placebo capsules thrice daily. All subjects were provided a standard diet (2,000 kcal daily) and participated in a moderate exercise of 30 min walk for five days a week. Additionally, the safety of this herbal formulation was evaluated by a series of acute, sub-acute toxicity and genotoxicity studies in animals and cellular models. Results: After eight weeks of supplementation, statistically significant net reductions in body weight (2.49 kg; p=0.00005) and BMI (0.96 kg/m2; p=0.00004) were observed in the LI10903F group versus placebo group. Additionally, significant increase in serum adiponectin concentration (p=0.0076) and significant decrease in serum ghrelin concentration (p=0.0066) were found in LI10903F group compared to placebo group. Adverse events were mild and were equally distributed between the two groups. Interestingly, LI10903F showed broad spectrum safety in a series of acute, sub-acute toxicity and genotoxicity studies. Conclusions: Results from the current research suggest that LI10903F or LOWAT is well-tolerated, safe and effective for weight management.
    Electronic ISSN: 1476-511X
    Topics: Biology
    Published by BioMed Central
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 56
    Publication Date: 2012-12-29
    Description: Background: The -493G/T polymorphism in the microsomal triglyceride transfer protein (MTP) gene is associated with lower serum low-density lipoprotein cholesterol (LDL-C) and triglyceride (TG) levels and longevity in several populations, but the results are inconsistent in different racial/ethnic groups. The current study was to investigate the plausible association of MTP -493G/T polymorphism with serum lipid levels and longevity in Zhuang long-lived families residing in Bama area, a famous home of longevity in Guangxi, China. Methods: The MTP -493G/T was genotyped by PCR-restriction fragment length polymorphism in 391 Bama Zhuang long-lived families (BLF, n = 1467, age 56.60 +/- 29.43 years) and four control groups recruited from Bama and out-of-Bama area with or without a familial history of exceptional longevity: Bama non-long-lived families (BNLF, n = 586, age 44.81 +/- 26.83 years), Bama non-Zhuang long-lived families (BNZLF, n = 444, age 52.09 +/- 31.91 years), Pingguo long-lived families (PLF, n = 658, age 50.83 +/- 30.30 years), and Pingguo non-long-lived families (PNLF, n = 539, age 38.74 +/- 24.69 years). Correlation analyses between genotypes and serum lipid levels and longevity were then performed. Results: No particularly favorable lipoprotein and clinical phenotypes were seen in BLF as compared to general families in the same area. Instead, the levels of total cholesterol (TC), TG, LDL-C, and the prevalence of dyslipidemia were significantly higher in the three Bama families as compared to the two non-Bama families (P 〈 0.01 for all). There were no differences in the allelic and genotypic frequencies among the tested cohorts (P 〉 0.05 for all), but the TT genotype tended to enrich in the three long-lived cohorts from both areas. In addition, the individuals harboring TT genotype exhibited lower LDL-C and TC levels in the overall populations and Bama populations with a region- and sex-specific pattern. Multiple linear regression analyses unraveled that LDL-C levels were correlated with genotypes in Bama combined population, BNLF, and the total population (P 〈 0.05 for each) but not in Pingguo populations; TC and HDL-C levels were correlated with genotypes in Bama combined population and BLF, respectively (P 〈 0.05 for each). Conclusions: MTP -493G/T polymorphism may play an important role in fashioning the serum lipid profiles of Bama populations, despite no direct association between MTP -493G/T and longevity was detected.
    Electronic ISSN: 1476-511X
    Topics: Biology
    Published by BioMed Central
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 57
    Publication Date: 2012-12-29
    Description: Background: RNA interference (RNAi) becomes an increasingly important and effective genetic tool to study the function of target genes by suppressing specific genes of interest. This system approach helps identify signaling pathways and cellular phase types by tracking intensity and/or morphological changes of cells. The traditional RNAi screening scheme, in which one siRNA is designed to knockdown one specific mRNA target, needs a large library of siRNAs and turns out to be time-consuming and expensive. Results: In this paper, we propose a conceptual model, called compressed sensing RNAi (csRNAi), which employs the unique combination of group of small interfering RNAs (siRNAs) to knockdown a much larger size of genes. This strategy is based on the fact that one gene can be partially bound with several small interfering RNAs (siRNAs) and conversely, one siRNA can bind to a few genes with distinct binding affinity. This model constructs a multi-to-multi correspondence between siRNAs and their targets, with siRNAs much fewer than mRNA targets, compared with the conventional scheme. Mathematically this problem involves an underdetermined system of equations (linear or nonlinear), which is ill-posed in general. However, the recently developed compressed sensing (CS) theory can solve this problem. We present a mathematical model to describe the csRNAi system based on both CS theory and biological concerns. To build this model, we first search nucleotide motifs in a target gene set. Then we propose a machine learning based method to find the effective siRNAs with novel features, such as image features and speech features to describe an siRNA sequence. Numerical simulations show that we can reduce the siRNA library to one third of that in the conventional scheme. In addition, the features to describe siRNAs outperform the existing ones substantially. Conclusions: This csRNAi system is very promising in saving both time and cost for large-scale RNAi screening experiments which may benefit the biological research with respect to cellular processes and pathways.
    Electronic ISSN: 1471-2105
    Topics: Biology , Computer Science
    Published by BioMed Central
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 58
    Publication Date: 2012-12-29
    Description: Background: Copy number variations (CNVs) are genomic structural variants that are found in healthy populations and have been observed to be associated with disease susceptibility. Existing methods for CNV detection are often performed on a sample-by-sample basis, which is not ideal for large datasets where common CNVs must be estimated by comparing the frequency of CNVs in the individual samples. Here we describe a simple and novel approach to locate genome-wide CNVs common to a specific population, using human ancestry as the phenotype. Results: We utilized our previously published Genome Alteration Detection Analysis (GADA) algorithm to identify common ancestry CNVs (caCNVs) and built a caCNV model to predict population structure. We identified a 73 caCNV signature using a training set of 225 healthy individuals from European, Asian, and African ancestry. The signature was validated on an independent test set of 300 individuals with similar ancestral background. The error rate in predicting ancestry in this test set was 2% using the 73 caCNV signature. Among the caCNVs identified, several were previously confirmed experimentally to vary by ancestry. Our signature also contains a caCNV region with a single microRNA (MIR270), which represents the first reported variation of microRNA by ancestry. Conclusions: We developed a new methodology to identify common CNVs and demonstrated its performance by building a caCNV signature to predict human ancestry with high accuracy. The utility of our approach could be extended to large case--control studies to identify CNV signatures for other phenotypes such as disease susceptibility and drug response.
    Electronic ISSN: 1471-2105
    Topics: Biology , Computer Science
    Published by BioMed Central
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 59
    Publication Date: 2012-12-29
    Description: Background: Understanding demographic histories, such as divergence time, patterns of gene flow, and population size changes, in ecologically diverging lineages provide implications for the process and maintenance of population differentiation by ecological adaptation. This study addressed the demographic histories in two independently derived lineages of flood-resistant riparian plants and their non-riparian relatives [Ainsliaea linearis (riparian) and A. apiculata (non-riparian); A. oblonga (riparian) and A. macroclinidioides (non-riparian); Asteraceae] using an isolation-with-migration (IM) model based on variation at 10 nuclear DNA loci. Results: The highest posterior probabilities of the divergence time parameters were estimated to be ca. 25,000 years ago for A. linearis and A. apiculata and ca. 9000 years ago for A. oblonga and A. macroclinidioides, although the confidence intervals of the parameters had broad ranges. The likelihood ratio tests detected evidence of historical gene flow between both riparian/non-riparian species pairs. The riparian populations showed lower levels of genetic diversity and a significant reduction in effective population sizes compared to the non-riparian populations and their ancestral populations. Conclusions: This study showed the recent origins of flood-resistant riparian plants, which are remarkable examples of plant ecological adaptation. The recent divergence and genetic signatures of historical gene flow among riparian/non-riparian species implied that they underwent morphological and ecological differentiation within short evolutionary timescales and have maintained their species boundaries in the face of gene flow. Comparative analyses of adaptive divergence in two sets of riparian/non-riparian lineages suggested that strong natural selection by flooding had frequently reduced the genetic diversity and size of riparian populations through genetic drift, possibly leading to fixation of adaptive traits in riparian populations. The two sets of riparian/non-riparian lineages showed contrasting patterns of gene flow and genetic differentiation, implying that each lineage showed different degrees of reproductive isolation and that they had experienced unique evolutionary and demographic histories in the process of adaptive divergence.
    Electronic ISSN: 1471-2148
    Topics: Biology
    Published by BioMed Central
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 60
    Publication Date: 2012-12-30
    Description: Background: HIV/AIDS has several means of transmission. Exposure to blood and other body fluids is a very important means of transmission. Healthcare workers are exposed to this disease mainly due to the nature of their work. This is an exploration of the perceptions of healthcare workers of the University of Gondar Hospital. Methods: Based on purposive sampling seven healthcare workers were selected from different departments in the hospital so that they could reflect on their perceptions. The selected healthcare workers were asked about the risks related to their work, their experience of HIV related hazards and their general views on the transmission of HIV. The main themes were identified for analysis and the views were summarized under the themes. Results: All the respondents were aware of the risk of acquiring HIV in healthcare settings. Some had experienced accidents that made them take post-exposure prophylaxis, and most witnessed accidents like needle-stick injuries to their colleagues. They also expressed their feelings that their workplace was not the best place to work at. Conclusion: Health professionals are well aware of the possibility of HIV transmission associated with their practice. Accidents like needle stick injuries are apparently common; and at the same time, the practice of healthcare workers towards using universal precautions looks poor.
    Electronic ISSN: 1756-0500
    Topics: Biology , Medicine
    Published by BioMed Central
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 61
    Publication Date: 2012-12-30
    Description: Background: Members of the family Syngnathidae share a unique reproductive mode termed male pregnancy. Males carry eggs in specialised brooding structures for several weeks and release free-swimming offspring. Here we describe a systematic investigation of pre-release development in syngnathid fishes, reviewing available data for 17 species distributed across the family. This work is complemented by in-depth examinations of the straight-nosed pipefish Nerophis ophidion, the black-striped pipefish Syngnathus abaster, and the potbellied seahorse Hippocampus abdominalis. Results: We propose a standardised classification of early syngnathid development that extends from the activation of the egg to the release of newborn. The classification consists of four developmental periods -- early embryogenesis, eye development, snout formation, and juvenile -- which are further divided into 11 stages. Stages are characterised by morphological traits that are easily visible in live and preserved specimens using incident-light microscopy. Conclusions: Our classification is derived from examinations of species representing the full range of brooding-structure complexity found in the Syngnathidae, including tail-brooding as well as trunk-brooding species, which represent independent evolutionary lineages. We chose conspicuous common traits as diagnostic features of stages to allow for rapid and consistent staging of embryos and larvae across the entire family. In view of the growing interest in the biology of the Syngnathidae, we believe that the classification proposed here will prove useful for a wide range of studies on the unique reproductive biology of these male-brooding fish.
    Electronic ISSN: 1471-213X
    Topics: Biology , Medicine
    Published by BioMed Central
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 62
    Publication Date: 2012-12-30
    Description: Background: Maize is a major crop plant, grown for human and animal nutrition, as well as a renewable resource forbioenergy. When looking at the problems of limited fossil fuels, the growth of the world's population or theworld's climate change, it is important to find ways to increase the yield and biomass of maize and to studyhow it reacts to specific abiotic and biotic stress situations. Within the OPTIMAS systems biology projectmaize plants were grown under a large set of controlled stress conditions, phenotypically characterised andplant material was harvested to analyse the effect of specific environmental conditions or developmentalstages. Transcriptomic, metabolomic, ionomic and proteomic parameters were measured from the same plantmaterial allowing the comparison of results across different omics domains. A data warehouse wasDescriptionThe OPTIMAS Data Warehouse (OPTIMAS-DW) is a comprehensive data collection for maize and integratesdata from different data domains such as transcriptomics, metabolomics, ionomics, proteomics andphenomics. Within the OPTIMAS project, a 44K oligo chip was designed and annotated to describe thefunctions of the selected unigenes. Several treatment- and plant growth stage experiments were performed andmeasured data were filled into data templates and imported into the data warehouse by a Java based importtool. A web interface allows users to browse through all stored experiment data in OPTIMAS-DW includingall data domains. Furthermore, the user can filter the data to extract information of particular interest. All datacan be exported into different file formats for further data analysis and visualisation. The data analysisintegrates data from different data domains and enables the user to find answers to different systems biologyquestions. Finally, maize specific pathway information is provided. Conclusions: With OPTIMAS-DW a data warehouse for maize was established, which is able to handle different datadomains, comprises several analysis results that will support researchers within their work and supportssystems biological research in particular. The system is available athttp://www.optimas-bioenergy.org/optimas_dw.
    Electronic ISSN: 1471-2229
    Topics: Biology
    Published by BioMed Central
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 63
    Publication Date: 2012-12-30
    Description: Background: Health control beliefs were postulated to be associated with health behaviour. However, the results of studies assessing these associations suggest that they might not be universal. Among young adults associations have been reported, but, the evidence is limited. The objective of this analysis was to re-examine these associations in a sample of university students in Germany.FindingsData from a multicentre cross-sectional study among university students in North Rhine-Westphalia, Germany was used (N=3,306). The Multidimensional Health Locus of Control Scale with three dimensions (one internal and two external) and six aspects of health behaviour (smoking habits, alcohol use, drug consumption, being over-/ or underweight, physical activity, and importance of healthy nutrition) were evaluated. Students with stronger internal locus of control scores paid more attention to healthy nutrition and displayed a higher level of physical activity. Individuals with a stronger belief in health professionals were less likely to use drugs and paid more attention to healthy nutrition. Furthermore, higher scores in the second external locus of control dimension (beliefs in luck or chance) were associated with a higher likelihood of current smoking, lower physical activity and less attention to healthy nutrition. Conclusions: Students engaged more strongly in unhealthy behaviour if they believed that luck determines health. In contrast, believing in having control over one's own health was associated with more healthy behaviour. These findings support the need to consider health control beliefs while designing preventive strategies in this specific population.
    Electronic ISSN: 1756-0500
    Topics: Biology , Medicine
    Published by BioMed Central
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 64
    Publication Date: 2012-12-30
    Description: Available online 29 December 2012 Publication year: 2012 Source: FEBS Open Bio A water-soluble selenoxide (DHS ox ) having a five-membered ring structure enables rapid and selective conversion of cysteinyl SH groups in a polypeptide chain into SS bonds in a wide pH and temperature range. It was previously demonstrated that the second-order rate constants for the SS formation with DHS ox would be proportional to the number of the free SH groups present in the substrate if there is no steric congestion around the SH groups. In the present study, kinetics of the SS formation with DHS ox was extensively studied at pH 4–10 and 25°C by using reduced ribonuclease A, recombinant hirudin variant (CX-397), insulin A- and B-chains, and relaxin A-chain, which have two to eight cysteine residues, as polythiol substrates. The obtained rate constants showed stochastic SS formation behaviors under most conditions. However, the rate constants for CX-397 at pH 8.0 and 10.0 were not proportional to the number of the free SH groups, suggesting that the SS intermediate ensembles possess densely packed structures under weakly basic conditions. The high two-electron redox potential of DHS ox (375 mV at 25°C) compared to L-cystine supported the high ability of DHS ox for SS formation in a polypeptide chain. Interestingly, the rate constants of the SS formation jumped up at a pH around the p K a value of the cysteinyl SH groups. The SS formation velocity was slightly decreased by addition of a denaturant due probably to the interaction between the denaturant and the peptide. The stochastic behaviors as well as the absolute values of the second-order rate constants in comparison to dithiothreitol (DTT red ) are useful to probe the chemical reactivity and conformation, hence the folding, of polypeptide chains. Graphical abstract Highlights ▸ DHS ox was applied as a SS-forming reagent for five polythiol peptides and DTT red . ▸ The SS formation velocities depend on the kind of substrate and solvent conditions. ▸ The SS-formation rate constants are proportional to the number of free SH groups. ▸ Folded structures and SH p K a modify the stochastic nature and absolute values of the rate constants. ▸ DHS ox is a useful probe of chemical reactivity and intermediate structures in oxidative protein folding.
    Electronic ISSN: 2211-5463
    Topics: Biology
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 65
    Publication Date: 2012-12-19
    Description: Background: In higher eukaryotes, gene expression is regulated at different levels. In particular, 3[prime]UTRs play a central role in translation, stability and subcellular localization of transcripts. In recent years, the development of high throughput sequencing techniques has facilitated the acquisition of transcriptional data at a genome wide level. However, annotation of the 3[prime] ends of genes is still incomplete, thus limiting the interpretation of the data generated. For example, we have previously reported two different genes, ADD2 and CPEB3, with conserved 3[prime]UTR alternative isoforms not annotated in the current versions of Ensembl and RefSeq human databases. Results: In order to evaluate the existence of other conserved 3[prime] ends not annotated in these databases we have now used comparative genomics and transcriptomics across several vertebrate species. In general, we have observed that 3[prime]UTR conservation is lost after the end of the mature transcript. Using this change in conservation before and after the 3[prime] end of the mature transcripts we have shown that many conserved ends were still not annotated. In addition, we used orthologous transcripts to predict 3[prime]UTR extensions and validated these predictions using total RNA sequencing data. Finally, we used this method to identify not annotated 3[prime] ends in rats and dogs. As a result, we report several hundred novel 3[prime]UTR extensions in rats and a few thousand in dogs. Conclusions: The methods presented here can efficiently facilitate the identification of not-yet-annotated conserved 3[prime]UTR extensions. The application of these methods will increase the confidence of orthologous gene models across vertebrates.
    Electronic ISSN: 1471-2164
    Topics: Biology
    Published by BioMed Central
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 66
    Publication Date: 2012-12-19
    Description: Background: Pineapple (Ananas comosus) is a tropical fruit crop of significant commercial importance. Although the physiological changes that occur during pineapple fruit development have been well characterized, little is known about the molecular events that occur during the fruit ripening process. Understanding the molecular basis of pineapple fruit ripening will aid the development of new varieties via molecular breeding or genetic modification. In this study we developed a 9277 element pineapple microarray and used it to profile gene expression changes that occur during pineapple fruit ripening. Results: Microarray analyses identified 271 unique cDNAs differentially expressed at least 1.5-fold between the mature green and mature yellow stages of pineapple fruit ripening. Among these 271 sequences, 184 share significant homology with genes encoding proteins of known function, 53 share homology with genes encoding proteins of unknown function and 34 share no significant homology with any database accession. Of the 237 pineapple sequences with homologs, 160 were up-regulated and 77 were down-regulated during pineapple fruit ripening. DAVID Functional Annotation Cluster (FAC) analysis of all 237 sequences with homologs revealed confident enrichment scores for redox activity, organic acid metabolism, metalloenzyme activity, glycolysis, vitamin C biosynthesis, antioxidant activity and cysteine peptidase activity, indicating the functional significance and importance of these processes and pathways during pineapple fruit development. Quantitative real-time PCR analysis validated the microarray expression results for nine out of ten genes tested. Conclusions: This is the first report of a microarray based gene expression study undertaken in pineapple. Our bioinformatic analyses of the transcript profiles have identified a number of genes, processes and pathways with putative involvement in the pineapple fruit ripening process. This study extends our knowledge of the molecular basis of pineapple fruit ripening and non-climacteric fruit ripening in general.
    Electronic ISSN: 1471-2229
    Topics: Biology
    Published by BioMed Central
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 67
    Publication Date: 2012-12-19
    Description: Background: Accumulation of extracellular matrix (ECM) and increased matrix metalloproteinase (MMP) activity are hallmarks of liver fibrosis. The aim of the present study was to develop a model of liver fibrosis combining ex vivo tissue culture of livers from CCl4 treated animals with an ELISA detecting a fragment of type III collagen generated in vitro by MMP-9 (C3M), known to be associated with liver fibrosis and to investigate cAMP modulation of MMP activity and liver tissue turnover in this model.FindingsIn vivo: Rats were treated for 8 weeks with CCl4/Intralipid. Liver slices were cultured for 48 hours. Levels of C3M were determined in the supernatants of slices cultured without treatment, treated with GM6001 (positive control) or treated with IBMX (phosphodiesterase inhibitor). Enzymatic activity of MMP-2 and MMP-9 were studied by gelatin zymography.Ex vivo: The levels of serum C3M increased 77% in the CCl4-treated rats at week 8 (p 〈 0.01); Levels of C3M increased significantly by 100% in fibrotic liver slices compared to controls after 48 hrs (p 〈 0.01). By adding GM6001 or IBMX to the media, C3M was restored to control levels. Gelatin zymography demonstrated CCl4-treated animals had highly increased MMP-9, but not MMP-2 activity, compared to slices derived from control animals. Conclusions: We have combined an ex vivo model of liver fibrosis with measurement of a biochemical marker of collagen degradation in the condition medium. This technology may be used to evaluate the molecular process leading to structural fibrotic changes, as collagen species are the predominant structural part of fibrosis. These data suggest that modulation of cAMP may play a role in regulation of collagen degradation associated with liver fibrosis.
    Electronic ISSN: 1756-0500
    Topics: Biology , Medicine
    Published by BioMed Central
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 68
    Publication Date: 2012-12-20
    Description: Background: Cia5a is a locus on rat chromosome 10 that regulates disease severity and joint damage in two models of rheumatoid arthritis, collagen- and pristane-induced arthritis (PIA). In this study, we aimed to identify cellular and molecular processes regulated by Cia5a using microarray-based gene expression analysis of synovial tissues from MHC identical DA (severe erosive disease) and DA.F344(Cia5a) congenics (mild non-erosive disease) rats. Results: Synovial tissues from six DA and eight DA.F344(Cia5a) rats were analyzed 21 days after the induction of PIA using the Illumina RatRef-12 BeadChip (21,922 genes) and selected data confirmed with qPCR. There was a significantly increased expression of pro-inflammatory mediators such as Il1b (5-fold), Il18 (3.9-fold), Cxcl1 (10-fold), Cxcl13 (7.5-fold) and Ccl7 (7.9-fold), and proteases like Mmp3 (23-fold), Mmp9 (32-fold), Mmp14 (4.4-fold) and cathepsins in synovial tissues from DA, with reciprocally reduced levels in congenics. mRNA levels of 47 members of the Spleen Tyrosine Kinase (Syk) pathway were significantly increased in DA synovial tissues compared with DA.F344(Cia5a), and included Syk (5.4-fold), Syk-activating receptors and interacting proteins, and genes regulated by Syk such as NFkB, and NAPDH oxidase complex genes. Nuclear receptors (NR) such as Rxrg, Pparg and Rev-erba were increased in the protected congenics, and so was the anti-inflammatory NR-target gene Scd1 (54-fold increase). Tnn (72-fold decrease) was the gene most significantly increased in DA. Conclusions: Analyses of gene expression in synovial tissues revealed that the arthritis severity locus Cia5a regulates the expression of key mediators of inflammation and joint damage, as well as the expression of members of the Syk pathway. This expression pattern correlates with disease severity and joint damage and along with the gene accounting for Cia5a could become a useful biomarker to identify patients at increased risk for severe and erosive disease. The identification of the gene accounting for Cia5a has the potential to generate a new and important target for therapy and prognosis.
    Electronic ISSN: 1471-2164
    Topics: Biology
    Published by BioMed Central
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 69
    Publication Date: 2012-12-20
    Description: Background: Traditional candidate gene approach has been widely used for the study of complex diseases including obesity. However, this approach is largely limited by its dependence on existing knowledge of presumed biology of the phenotype under investigation. Our combined strategy of comparative genomics and chromosomal heritability estimate analysis of obesity traits, subscapular skinfold thickness and back-fat thickness in Korean cohorts and pig (Sus scrofa), may overcome the limitations of candidate gene analysis and allow us to better understand genetic predisposition to human obesity. Results: We found common genes including FTO, the fat mass and obesity associated gene, identified from significant SNPs by association studies of each trait. These common genes were related to blood pressure and arterial stiffness (P = 1.65E-05) and type 2 diabetes (P = 0.00578). Through the estimation of variance of genetic component (heritability) for each chromosome by SNPs, we observed a significant positive correlation (r = 0.479) between genetic contributions of human and pig to obesity traits. Furthermore, we noted that the phenotypic variance for obesity can be explained dominantly by chromosome 2, which is syntenic to pig chromosomes 3 and 15. Conclusions: Obesity genetics still awaits further discovery. Navigating syntenic regions suggests obesity candidate genes on chromosome 2 that are previously known to be associated with obesity-related diseases: MRPL33, PARD3B, ERBB4, STK39, and ZNF385B.
    Electronic ISSN: 1471-2164
    Topics: Biology
    Published by BioMed Central
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 70
    Publication Date: 2012-12-20
    Description: Background: Phenotypic evolution in animals is thought to be driven in large part by differences in gene expression patterns, which can result from sequence changes in cis-regulatory elements (cis-changes) or from changes in the expression pattern or function of transcription factors (trans-changes). While isolated examples of trans-changes have been identified, the scale of their overall contribution to regulatory and phenotypic evolution remains unclear. Results: Here, we attempt to examine the prevalence of trans-effects and their potential impact on gene expression patterns in vertebrate evolution by comparing the function of identical human tissue-specific enhancer sequences in two highly divergent vertebrate model systems, mouse and zebrafish. Among 47 human conserved non-coding elements (CNEs) tested in transgenic mouse embryos and in stable zebrafish lines, at least one species-specific expression domain was observed in the majority (83%) of cases, and 36% presented dramatically different expression patterns between the two species. Although some of these discrepancies may be due to the use of different transgenesis systems in mouse and zebrafish, in some instances we found an association between differences in enhancer activity and changes in the endogenous gene expression patterns between mouse and zebrafish, suggesting a potential role for trans-changes in the evolution of gene expression. Conclusions: In total, our results: (i) serve as a cautionary tale for studies investigating the role of human enhancers in different model organisms, and (ii) suggest that changes in the trans environment may play a significant role in the evolution of gene expression in vertebrates.
    Electronic ISSN: 1471-2164
    Topics: Biology
    Published by BioMed Central
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 71
    Publication Date: 2012-12-20
    Description: Background: Tourette Syndrome (TS) is a neuropsychiatric disorder in children characterized by motor andverbal tics. Although several genes have been suggested in the etiology of TS, the geneticmechanisms remain poorly understood. Methods: Using cytogenetics and FISH analysis, we identified an apparently balancedt(6,22)(q16.2;p13) in a male patient with TS and obsessive-compulsive disorder (OCD). Inorder to map the breakpoints and to identify additional submicroscopic rearrangements, weperformed whole genome mate-pair sequencing and CGH-array analysis on DNA from theproband. Results: Sequence and CGH array analysis revealed a 400 kb deletion located 1.3 Mb telomeric of thechromosome 6q breakpoint, which has not been reported in controls. The deletion affectsthree genes (GPR63, NDUFA4 and KLHL32) and overlaps a region previously found deletedin a girl with autistic features and speech delay. The proband's mother, also a carrier of thetranslocation, was diagnosed with OCD and shares the deletion. We also describe a furtherpotentially related rearrangement which, while unmapped in Homo sapiens, was consistentwith the chimpanzee genome. Conclusions: We conclude that genome-wide sequencing at relatively low resolution can be used for theidentification of submicroscopic rearrangements.We also show that large rearrangements may escape detection using standard analysis ofwhole genome sequencing data. Our findings further provide a candidate region for TS andOCD on chromosome 6q16.
    Electronic ISSN: 1471-2350
    Topics: Biology , Medicine
    Published by BioMed Central
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 72
    Publication Date: 2012-12-20
    Description: Background: Secretoglobin 1A1 (SCGB 1A1), also called Clara cell secretory protein, is the most abundantly secreted protein of the airway. The SCGB1A1 gene has been characterized in mammals as a single copy in the genome. However, analysis of the equine genome suggested that horses might have multiple SCGB1A1 gene copies. Non-ciliated lung epithelial cells produce SCGB 1A1 during inhalation of noxious substances to counter airway inflammation. Airway fluid and lung tissue of horses with recurrent airway obstruction (RAO), a chronic inflammatory lung disease affecting mature horses similar to environmentally induced asthma of humans, have reduced total SCGB 1A1 concentration. Herein, we investigated whether horses have distinct expressed SCGB1A1 genes; whether the transcripts are differentially expressed in tissues and in inflammatory lung disease; and whether there is cell specific protein expression in tissues. Results: We identified three SCGB1A1 gene copies on equine chromosome 12, contained within a 512-kilobase region. Bioinformatic analysis showed that SCGB1A1 genes differ from each other by 8 to 10 nucleotides, and that they code for different proteins. Transcripts were detected for SCGB1A1 and SCGB1A1A, but not for SCGB1A1P. The SCGB1A1P gene had most inter-individual variability and contained a non-sense mutation in many animals, suggesting that SCGB1A1P has evolved into a pseudogene. Analysis of SCGB1A1 and SCGB1A1A sequences by endpoint-limiting dilution PCR identified a consistent difference affecting 3 bp within exon 2, which served as a gene-specific "signature". Assessment of gene- and organ-specific expression by semiquantitative RT-PCR of 33 tissues showed strong expression of SCGB1A1 and SCGB1A1A in lung, uterus, Fallopian tube and mammary gland, which correlated with detection of SCGB 1A1 protein by immunohistochemistry. Significantly altered expression of the ratio of SCGB1A1A to SCGB1A1 was detected in RAO-affected animals compared to controls, suggesting different roles for SCGB 1A1 and SCGB 1A1A in this inflammatory condition. Conclusions: This is the first report of three SCGB1A1 genes in a mammal. The two expressed genes code for proteins predicted to differ in function. Alterations in the gene expression ratio in RAO suggest cell and tissue specific regulation and functions. These findings may be important for understanding of lung and reproductive conditions.
    Electronic ISSN: 1471-2164
    Topics: Biology
    Published by BioMed Central
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 73
    Publication Date: 2012-12-20
    Description: Background: To determine the general appearance of normal axillary lymph nodes (LNs) in real-time tissue sonoelastography and to explore the method[prime]s potential value in the prediction of LN metastases. Methods: Axillary LNs in healthy probands (n=165) and metastatic LNs in breast cancer patients (n=15) were examined with palpation, B-mode ultrasound, Doppler and sonoelastography (assessment of the elasticity of the cortex and the medulla). The elasticity distributions were compared and sensitivity (SE) and specificity (SP) were calculated. In an exploratory analysis, positive and negative predictive values (PPV, NPV) were calculated based upon the estimated prevalence of LN metastases in different risk groups. Results: In the elastogram, the LN cortex was significantly harder than the medulla in both healthy (p=0.004) and metastatic LNs (p=0.005). Comparing healthy and metastatic LNs, there was no difference in the elasticity distribution of the medulla (p=0.281), but we found a significantly harder cortex in metastatic LNs (p=0.006). The SE of clinical examination, B-mode ultrasound, Doppler ultrasound and sonoelastography was revealed to be 13.3%, 40.0%, 14.3% and 60.0%, respectively, and SP was 88.4%, 96.8%, 95.6% and 79.6%, respectively. The highest SE was achieved by the disjunctive combination of B-mode and elastographic features (cortex 〉3mm in B-mode or blue cortex in the elastogram, SE=73.3%). The highest SP was achieved by the conjunctive combination of B-mode ultrasound and elastography (cortex 〉3mm in B-mode and blue cortex in the elastogram, SP=99.3%). Conclusions: Sonoelastography is a feasible method to visualize the elasticity distribution of LNs. Moreover, sonoelastography is capable of detecting elasticity differences between the cortex and medulla, and between metastatic and healthy LNs. Therefore, sonoelastography yields additional information about axillary LN status and can improve the PPV, although this method is still experimental.
    Electronic ISSN: 1471-2342
    Topics: Biology
    Published by BioMed Central
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 74
    Publication Date: 2012-12-20
    Description: Background: The use of food-grade Lactic Acid Bacteria (LAB) as DNA delivery vehicles represents an attractive strategy to deliver DNA vaccines at the mucosal surfaces as they are generally regarded as safe (GRAS). We previously showed that either native Lactococcus lactis (LL) or recombinant invasive LL expressing Fibronectin Binding Protein A of Staphylococcus aureus (LL-FnBPA+) or Internalin A of Listeria monocytogenes (LL-InlA+), were able to deliver and trigger DNA expression by epithelial cells, either in vitro or in vivo. InlA does not bind to its receptor, the murine E-cadherin, thus limiting the use of LL-InlA+in in vivo murine models. Moreover, FnBPA binds to its receptors, integrins, via fibronectin introducing another limiting factor. In order to avoid the limitations of LL-InlA+and LL-FnBPA+, a new L. lactis strain was engineered to produce a previously described mutated form of InlA (LL-mInlA+) allowing the binding of mInlA on murine E-cadherin. Results: After showing the expression of mInLA at the surface of LL-mInlA+strain, in vitro gentamycin survival assay in Caco-2 cells showed that LL-mInlA+is 1000 times more invasive than LL. LL-mInlA+invasivity was also validated by fluorescence microscopy. LL and LL-mInlA+were transformed with pValacBLG, a plasmid containing the cDNA of bovine beta-Lactoglobulin (BLG), resulting in strains LL-BLG and LL-mInlA+BLG. The plasmid transfer in vitro using LL-mInlA+BLG was increased 10 times compared to LL-BLG. Moreover, the number of mice producing BLG in isolated enterocytes after oral administration of LL-mInlA+BLG in vivo was slightly higher than after oral administration of LL-BLG. Conclusions: We confirmed in this study that the production of mInlA at the surface of L. lactis is a promising strategy for plasmid transfer in vitro and in vivo.
    Electronic ISSN: 1471-2180
    Topics: Biology
    Published by BioMed Central
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 75
    Publication Date: 2012-12-20
    Description: Background: The 22q11.2 deletion syndrome (22q11.2DS) is caused by hemizygous microdeletions on chromosome 22q11.2 with highly variable physical and neuropsychiatric manifestations. We explored the genotype-phenotype relationship in a relatively large 22q11.2DS cohort treated and monitored in our clinic using comprehensive clinical evaluation and detailed molecular characterization of the deletion. Methods: Molecular analyses in 142 subjects with 22q11.2DS features were performed by FISH and MLPA methods. Participants underwent clinical assessment of physical symptoms and structured psychiatric and cognitive evaluation. Results: Deletions were found in 110 individuals including one with an atypical nested distal deletion which was missed by the FISH test. Most subjects (88.2%) carried the 3Mb typically deleted region and 11.8% carried 4 types of deletions differing in size and location. No statistically significant genotype-phenotype correlations were found between deletion type and clinical data although some differences in hypocalcemia and cardiovascular anomalies were noted.Analysis of the patient with the distal nested deletion suggested a redundancy of genes causing the physical and neuropsychiatric phenotype in 22q11.2DS and indicating that the psychiatric and cognitive trajectories may be governed by different genes. Conclusions: MLPA is a useful and affordable molecular method combining accurate diagnosis and detailed deletion characterization. Variations in deletion type and clinical manifestations impede the detection of significant differences in samples of moderate size, but analysis of individuals with unique deletions may provide insight into the underlying biological mechanisms.Future genotype-phenotype studies should involve large multicenter collaborations employing uniform clinical standards and high-resolution molecular methods.
    Electronic ISSN: 1471-2350
    Topics: Biology , Medicine
    Published by BioMed Central
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 76
    Publication Date: 2012-12-20
    Description: Background: In eukaryotic cells, dynamin and flotillin are involved in processes such as endocytosis and lipid raft formation, respectively. Dynamin is a GTPase that exerts motor-like activity during the pinching off of vesicles, while flotillins are coiled coil rich membrane proteins with no known enzymatic activity. Bacteria also possess orthologs of both classes of proteins, but their function has been unclear. Results: We show that deletion of the single dynA or floT genes lead to no phenotype or a mild defect in septum formation in the case of the dynA gene, while dynA floT double mutant cells were highly elongated and irregularly shaped, although the MreB cytoskeleton appeared to be normal. DynA colocalizes with FtsZ, and the dynA deletion strain shows aberrant FtsZ rings in a subpopulation of cells. The mild division defect of the dynA deletion is exacerbated by an additional deletion in ezrA, which affects FtsZ ring formation, and also by the deletion of a late division gene (divIB), indicating that DynA affects several steps in cell division. DynA and mreB deletions generated a synthetic defect in cell shape maintenance, showing that MreB and DynA play non-epistatic functions in cell shape maintenance. TIRF microscopy revealed that FloT forms many dynamic membrane assemblies that frequently colocalize with the division septum. The deletion of dynA did not change the pattern of localization of FloT, and vice versa, showing that the two proteins play non redundant roles in a variety of cellular processes. Expression of dynamin or flotillin T in eukaryotic S2 cells revealed that both proteins assemble at the cell membrane. While FloT formed patch structures, DynA built up tubulated structures extending away from the cells. Conclusions: Bacillus subtilis dynamin ortholog DynA plays a role during cell division and in cell shape maintenance. It shows a genetic link with flotillin T, with both proteins playing non-redundant functions at the cell membrane, where they assemble even in the absence of any bacterial cofactor.
    Electronic ISSN: 1471-2180
    Topics: Biology
    Published by BioMed Central
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 77
    Publication Date: 2012-12-20
    Description: Background: To derive post-genomic, neutral insight into the peptidoglycan (PG) distribution among organisms, we mined 1,644 genomes listed in the Carbohydrate-Active Enzymes database for the presence of a minimal 3-gene set that is necessary for PG metabolism. This gene set consists of one gene from the glycosyltransferase family GT28, one from family GT51 and at least one gene belonging to one of five glycoside hydrolase families (GH23, GH73, GH102, GH103 and GH104). Results: None of the 103 Viruses or 101 Archaea examined possessed the minimal 3-gene set, but this set was detected in 1/42 of the Eukarya members (Micromonas sp., coding for GT28, GT51 and GH103) and in 1,260/1,398 (90.1%) of Bacteria, with a 100% positive predictive value for the presence of PG. Pearson correlation test showed that GT51 family genes were significantly associated with PG with a value of 0.963 and a p value less than 10-3. This result was confirmed by a phylogenetic comparative analysis showing that the GT51-encoding gene was significantly associated with PG with a Pagel's score of 60 and 51 (percentage of error close to 0%). Phylogenetic analysis indicated that the GT51 gene history comprised eight loss and one gain events, and suggested a dynamic on-going process. Conclusions: Genome analysis is a neutral approach to explore prospectively the presence of PG in uncultured, sequenced organisms with high predictive values.
    Electronic ISSN: 1471-2180
    Topics: Biology
    Published by BioMed Central
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 78
    Publication Date: 2012-12-20
    Description: Background: Toxin complex (Tc) family proteins were first identified as insecticidal toxins in Photorhabdus luminescens and have since been found in a wide range of bacteria. The genome of Yersinia pestis, the causative agent of bubonic plague, contains a locus that encodes the Tc protein homologues YitA, YitB, YitC, and YipA and YipB. Previous microarray data indicate that the Tc genes are highly upregulated by Y. pestis while in the flea vector; however, their role in the infection of fleas and pathogenesis in the mammalian host is unclear. Results: We show that the Tc proteins YitA and YipA are highly produced by Y. pestis while in the flea but not during growth in brain heart infusion (BHI) broth at the same temperature. Over-production of the LysR-type regulator YitR from an exogenous plasmid increased YitA and YipA synthesis in broth culture. The increase in production of YitA and YipA correlated with the yitR copy number and was temperature-dependent. Although highly synthesized in fleas, deletion of the Tc proteins did not alter survival of Y. pestis in the flea or prevent blockage of the proventriculus. Furthermore, YipA was found to undergo post-translational processing and YipA and YitA are localized to the outer membrane of Y. pestis. YitA was also detected by immunofluorescence microscopy on the surface of Y. pestis. Both YitA and YipA are produced maximally at low temperature but persist for several hours after transfer to 37[degree sign]C. Conclusions: Y. pestis Tc proteins are highly expressed in the flea but are not essential for Y. pestis to stably infect or produce a transmissible infection in the flea. However, YitA and YipA localize to the outer membrane and YitA is exposed on the surface, indicating that at least YitA is present on the surface when Y. pestis is transmitted into the mammalian host from the flea.
    Electronic ISSN: 1471-2180
    Topics: Biology
    Published by BioMed Central
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 79
    Publication Date: 2012-12-20
    Description: Background: Fermentative bacteria offer the potential to convert lignocellulosic waste-streams into biofuels such as hydrogen (H2) and ethanol. Current fermentative H2 and ethanol yields, however, are below theoretical maxima, vary greatly among organisms, and depend on the extent of metabolic pathways utilized. For fermentative H2 and/or ethanol production to become practical, biofuel yields must be increased. We performed a comparative meta-analysis of (i) reported end-product yields, and (ii) genes encoding pyruvate metabolism and end-product synthesis pathways to identify suitable biomarkers for screening a microorganism's potential of H2 and/or ethanol production, and to identify targets for metabolic engineering to improve biofuel yields. Our interest in H2 and/or ethanol optimization restricted our meta-analysis to organisms with sequenced genomes and limited branched end-product pathways. These included members of the Firmicutes, Euryarchaeota, and Thermotogae. Results: Bioinformatic analysis revealed that the absence of genes encoding acetaldehyde dehydrogenase and bifunctional acetaldehyde/alcohol dehydrogenase (AdhE) in Caldicellulosiruptor, Thermococcus, Pyrococcus, and Thermotoga species coincide with high H2 yields and low ethanol production. Organisms containing genes (or activities) for both ethanol and H2 synthesis pathways (i.e. Caldanaerobacter subterraneus subsp. tengcongensis, Ethanoligenens harbinense, and Clostridium species) had relatively uniform mixed product patterns. The absence of hydrogenases in Geobacillus and Bacillus species did not confer high ethanol production, but rather high lactate production. Only Thermoanaerobacter pseudethanolicus produced relatively high ethanol and low H2 yields. This may be attributed to presence of genes encoding proteins that promote NADH production. Lactate dehydrogenase and pyruvate:formate lyase are not conducive for ethanol and/or H2 production. While the type(s) of encoded hydrogenases appear to have little impact on H2 production in organisms that do not encode ethanol producing pathways, they do influence reduced end-product yields in those that do. Conclusions: Here we show that composition of genes encoding pathways involved in pyruvate catabolism and end-product synthesis pathways can be used to approximate potential end-product distribution patterns. We have identified a number of genetic biomarkers for streamlining ethanol and H2 producing capabilities. By linking genome content, reaction thermodynamics, and end-product yields, we offer potential targets for optimization of either ethanol or H2 yields through metabolic engineering.
    Electronic ISSN: 1471-2180
    Topics: Biology
    Published by BioMed Central
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 80
    Publication Date: 2012-12-20
    Description: Background: Endolysins produced by bacteriophages lyse bacteria, and are thus considered a novel type of antimicrobial agent. Several endolysins from Bacillus phages or prophages have previously been characterized and used to target Bacillus strains that cause disease in animals and humans. B. thuringiensis phage BtCS33 is a Siphoviridae family phage and its genome has been sequenced and analyzed. In the BtCS33 genome, orf18 was found to encode an endolysin protein (PlyBt33). Results: Bioinformatic analyses showed that endolysin PlyBt33 was composed of two functional domains, the N-terminal catalytic domain and the C-terminal cell wall binding domain. In this study, the entire endolysin PlyBt33, and both the N- and C-termini,were expressed in Escherichia coli and then purified. The lytic activities of PlyBt33 and its N-terminus were tested on bacteria. Both regions exhibited lytic activity, although PlyBt33 showed a higher lytic activity than the N-terminus. PlyBt33 exhibited activity against all Bacillus strains tested from five different species, but was not active against Gram-negative bacteria. Optimal conditions for PlyBt33 reactivity were pH 9.0 and 50[degree sign]C. PlyBt33 showed high thermostability, with 40% of initial activity remaining following 1 h of treatment at 60[degree sign]C. The C-terminus of PlyBt33 bound to B. thuringiensis strain HD-73 and Bacillus subtilis strain 168. This cell wall binding domain might be novel, as its amino acid sequence showed little similarity to previously reported endolysins. Conclusions: PlyBt33 showed potential as a novel antimicrobial agent at a relatively high temperature and had a broad lytic spectrum within the Bacillus genus. The C-terminus of PlyBt33 might be a novel kind of cell wall binding domain.
    Electronic ISSN: 1471-2180
    Topics: Biology
    Published by BioMed Central
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 81
    Publication Date: 2012-12-20
    Description: Background: In plants, the multistep phosphorelay signaling pathway mediates responses to environmental factors and plant hormones. This system is composed of three successive partners: hybrid Histidine-aspartate Kinases (HKs), Histidine-containing Phosphotransfer proteins (HPts), and Response Regulators (RRs). Among the third partners, B-type RR family members are the final output elements of the pathway; they act as transcription factors and clearly play a pivotal role in the early response to cytokinin in Arabidopsis. While interactions studies between partners belonging to the multistep phosphorelay system are mainly focused on protagonists involved in cytokinin or ethylene pathways, very few reports are available concerning partners of osmotic stress signaling pathway. Results: In Populus, we identified eight B-type RR proteins, RR12-16, 19, 21 and 22 in the Dorskamp genotype. To assess HPt/B-type RR interactions and consequently determine potential third partners in the osmosensing multistep phosphorelay system, we performed global yeast two-hybrid (Y2H) assays in combination with Bimolecular Fluorescence Complementation (BiFC) assays in plant cells. We found that all B-type RRs are able to interact with HPt predominant partners (HPt2, 7 and 9) of HK1, which is putatively involved in the osmosensing pathway. However, different profiles of interaction are observed depending on the studied HPt. HPt/RR interactions displayed a nuclear localization, while the nuclear and cytosolic localization of HPt and nuclear localization of RR proteins were validated. Although the nuclear localization of HPt/RR interaction was expected, this work constitutes the first evidence of such an interaction in plants. Furthermore, the pertinence of this partnership is reinforced by highlighting a co-expression of B-type RR transcripts and the other partners (HK1 and HPts) belonging to a potential osmosensing pathway. Conclusion: Based on the interaction studies between identified B-type RR and HPt proteins, and the co-expression analysis of transcripts of these potential partners in poplar organs, our results favor the model that RR12, 13, 14, 16 and 19 are able to interact with the main partners of HK1, HPt2, 7 and 9, and this HPt/RR interaction occurs within the nucleus. On the whole, the five B-type RRs of interest could be third protagonists putatively involved in the osmosensing signaling pathway in Populus.
    Electronic ISSN: 1471-2229
    Topics: Biology
    Published by BioMed Central
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 82
    Publication Date: 2012-12-20
    Description: Background: A measles outbreak was detected at Ndanga Hospital in Zaka district Masvingo Province on the 5th of May 2010 and there were five deaths. Source of infection was not known and an investigation was carried out to determine factors associated with contracting measles in Zaka district.Materials and methodsA 1:1 unmatched case control study was conducted. A case was a person residing in Zaka district who developed signs and symptoms of measles or tested IgM positive from 06 May 2010 to 30 August 2010. A control was a person residing in the same community who did not have history of signs and symptoms of measles during the same period. A structured interviewer administered questionnaire (translated into shona) was used to solicit information from cases and controls. Ethical consideration like written consent from all participants, respect and confidentiality were observed. Permission to carry out the study was obtained from the medical research Council of Zimbabwe and the provincial Medical Directors Masvingo. Epi info was used to calculate frequencies, odds ratios and perform logistic regression to control for confounding variables.FindingsA total of 110 cases and 110 controls were recruited. Most cases (63.03%) were from the apostolic sect while 44.7% of controls were from orthodox churches. Contact with a measles case [AOR= 41.14, 95% CI (7.47-226.5)],being unvaccinated against measles [AOR= 3.96, 95%CI (2.58-6.08)] and not receiving additional doses of measles vaccine [AOR 5.48, 95% CI (2.16-11.08)] were independent risk factor for contracting measles . Measles vaccination coverage for Zaka district was 75%. The median duration for seeking treatment after onset of illness was three days (Q1=2; Q3=7). There were no emergency preparedness plans in place. Conclusion: This outbreak occurred due to a large number of unvaccinated children and a boarding school that facilitated person to person transmission. We recommend mandatory vaccination for all children before enrolling into schools. As a result of the study one day training on outbreak management and surveillance was done with all District Nursing Officers and Environmental Health Officers in personnel in the province.
    Electronic ISSN: 1756-0500
    Topics: Biology , Medicine
    Published by BioMed Central
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 83
    Publication Date: 2012-12-20
    Description: Available online 19 December 2012 Publication year: 2012 Source: FEBS Open Bio The green fluorescent protein (GFP) is the most commonly used reporter protein for monitoring gene expression and protein localization in a variety of living and fixed cells, including not only prokaryotes, but also eukaryotes, e.g., yeasts, mammals, plants and fish. In general, it is thought that GFP is nontoxic to cells, although there are some reports on the side effect of GFP. However, details of the molecular mechanism concerning the side effect of GFP remain unclear. Here we show that Ku80, but not XRCC4, plays an important role in the mechanism of the resistance to cytotoxicity induced by enhanced GFP (EGFP). EGFP inhibited both cell proliferation and colony formation, and induced cell death in Ku80-deficient hamster cells, i.e., xrs-6 cells. In addition, Ku80 attenuated EGFP-induced cytotoxicity in the xrs-6 cells. No EGFP-induced cytotoxicity was observed in the NHEJ core protein XRCC4-deficient hamster cells, i.e., XR-1 cells. Furthermore, EGFP markedly enhanced X-ray-induced cytotoxicity in the xrs-6 cells. These results suggest that Ku80 plays a key role in the novel NHEJ-independent defense mechanism against EGFP-induced cytotoxicity. Caution should be taken in considering of the potential influence by the stress response mechanism, namely, the Ku80-dependent elimination mechanism of EGFP-induced cytotoxicity, being activated, even when using EGFP-expressing cells in which Ku80 functions normally.
    Electronic ISSN: 2211-5463
    Topics: Biology
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 84
    Publication Date: 2012-12-21
    Description: Background: The localized scleroderma (LS) known as morphea, presents a variety of clinical manifestations that can include systemic involvement. Current classification schemes divide morphea into categories based solely on cutaneous morphology, without reference to systemic disease or autoimmune phenomena. This classification is likely incomplete. Autoimmune phenomena such as vitiligo and Hashimoto thyroiditis associated with LS have been reported in some cases suggesting an autoimmune basis. To our knowledge this is the first case of a morphea forming part of a multiple autoimmune syndrome (MAS) and presenting simultaneously with autoimmune thrombocytopenic purpura and central nervous system vasculitis.Case presentationWe report an uncommon case of a white 53 year old female patient with LS as part of a multiple autoimmune syndrome associated with pneumonitis, autoimmune thrombocytopenic purpura and central nervous system vasculitis presenting a favorable response with thrombopoietin receptor agonists, pulses of methylprednisolone and cyclophosphamide. Conclusion: Is likely that LS have an autoimmune origin and in this case becomes part of MAS, which consist on the presence of three or more well-defined autoimmune diseases in a single patient.
    Electronic ISSN: 1756-0500
    Topics: Biology , Medicine
    Published by BioMed Central
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 85
    Publication Date: 2012-12-21
    Description: Background: Extensive research effort has advanced our understanding of Caenorhabditis as a model system, but its natural association with bacteria remains to be explored in an ecological context. Explored associations vary vastly from mutualistic to parasitic. Serratia marcescens has been shown to be pathogenic to Caenorhabditis with a fitness cost. The recent isolation of an entomopathogenic Caenorhabditis briggsae KT0001/S. marcescens SCBI association from the wild has allowed us to examine under laboratory conditions whether such an association poses a serious cost to Caenorhabditis as previously surmised for other Serratia. Results: A fecundity table of Caenorhabditis briggsae KT0001 fed on S. marcescens SCBI and the control fed on E. coli OP50 is presented. We found no significant difference in survivorship or total fecundity between the S. marcescens SCBI fed and E. coli OP50 fed Caenorhabditis briggsae KT0001. Only the mean onset of reproduction was significantly different between the two groups with E. coli fed C. briggsae maturing earlier (2.12 days) than those fed on Serratia (2.42 days). Conclusion: S. marcescens SCBI is not highly pathogenic to C. briggsae KT0001 indicating that the entomopathogenicity reported for this association may be beneficial for both the nematode and bacteria. In light of the fact that hitherto conducted experimental tests conform to widely held view that Serratia are highly pathogenic to Caenorhabditis, the absence of a high fitness cost for C. briggsae we report here may indicate that this entomopathogenic association is non-transient suggesting nematode/bacterial associations in the wild may vary greatly. Consequently, broad generalizations about nematode/bacterial associations should be interpreted with care.
    Electronic ISSN: 1756-0500
    Topics: Biology , Medicine
    Published by BioMed Central
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 86
    Publication Date: 2012-12-21
    Description: Available online 20 December 2012 Publication year: 2012 Source: Cell Reports In the fission yeast Schizosaccharomyces pombe , a chromosomal imprinting event controls the asymmetric pattern of mating-type switching. The orientation of DNA replication at the mating-type locus is instrumental in this process. However, the factors leading to imprinting are not fully identified and the mechanism is poorly understood. Here, we show that the replication fork pause at the mat1 locus ( MPS1 ), essential for imprint formation, depends on the lysine-specific demethylase Lsd1. We demonstrate that either Lsd1 or Lsd2 amine oxidase activity is required for these processes, working upstream of the imprinting factors Swi1 and Swi3 (homologs of mammalian Timeless and Tipin, respectively). We also show that the Lsd1/2 complex controls the replication fork terminators, within the rDNA repeats. These findings reveal a role for the Lsd1/2 demethylases in controlling polar replication fork progression, imprint formation, and subsequent asymmetric cell divisions. Graphical abstract Highlights ► The lysine-specific demethylase, Lsd1, is a mating-type switching mutant ► Lsd1 is essential for replication fork pausing at the mat1 locus ► Lsd1 is essential for replication fork arrest at the replication fork block at rDNA loci ► Lsd1 and Lsd2 act in a redundant manner for replication fork pausing
    Electronic ISSN: 2211-1247
    Topics: Biology
    Published by Elsevier on behalf of Cell Press.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 87
    Publication Date: 2012-12-22
    Description: Available online 21 December 2012 Publication year: 2012 Source: Cell Reports Chromatin dynamics play a central role in maintaining genome integrity, but how this is achieved remains largely unknown. Here, we report that microrchidia CW-type zinc finger 2 (MORC2), an uncharacterized protein with a derived PHD finger domain and a conserved GHKL-type ATPase module, is a physiological substrate of p21-activated kinase 1 (PAK1), an important integrator of extracellular signals and nuclear processes. Following DNA damage, MORC2 is phosphorylated on serine 739 in a PAK1-dependent manner, and phosphorylated MORC2 regulates its DNA-dependent ATPase activity to facilitate chromatin remodeling. Moreover, MORC2 associates with chromatin and promotes gamma-H2AX induction in a PAK1 phosphorylation-dependent manner. Consequently, cells expressing MORC2-S739A mutation displayed a reduction in DNA repair efficiency and were hypersensitive to DNA-damaging agent. These findings suggest that the PAK1-MORC2 axis is critical for orchestrating the interplay between chromatin dynamics and the maintenance of genomic integrity through sequentially integrating multiple essential enzymatic processes. Graphical abstract Highlights ► MORC2 is a DNA damage-responsive phosphoprotein activated by PAK1 kinase ► MORC2 regulates phosphorylation-coupled, ATPase-dependent chromatin remodeling ► MORC2 facilitates gamma-H2AX induction independently of PIKK kinases ► MORC2 promotes DSB repair in a PAK1 phosphorylation-dependent manner
    Electronic ISSN: 2211-1247
    Topics: Biology
    Published by Elsevier on behalf of Cell Press.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 88
    Publication Date: 2012-11-09
    Description: First paragraph (this article has no abstract)What is regeneration? {1st level heading}Historically, philosophers, naturalists and biologists alike have referred to the restoration of missing body parts after traumatic injury as regeneration. While still valid today, the concept of regeneration has expanded through the years to include a diverse set of phenomena. For instance, August Weisman considered physiological cell renewal to be regeneration and wrote so in a chapter dedicated to regeneration in his seminal 1893 book The Germ Plasm: 'the functions of certain organs depend on the fact that their parts continually undergo destruction, and are then correspondingly renewed. In this case it is the process of life itself, and not an external enemy, that destroys the life of a cell' [1].
    Electronic ISSN: 1741-7007
    Topics: Biology
    Published by BioMed Central
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 89
    Publication Date: 2012-11-09
    Description: Background The robust identification of isotope patterns originating from peptides being analyzed through mass spectrometry (MS) is often significantly hampered by noise artifacts and the interference of overlappingpatterns arising e.g. from post-translational modifications. As the classification of the recorded data points into either 'noise' or 'signal' lies at the very root of essentially every proteomic application, the quality of the automated processing of mass spectra can significantly influence the way the data might be interpreted within a given biological context.Results We propose non-negative least squares/non-negative least absolute deviation regression to fit a raw spectrum by templates imitating isotope patterns. In a carefully designed validation scheme, we show that the method exhibits excellent performance in pattern picking. It is demonstrated that the method is able to disentangle complicated overlaps of patterns. Conclusions: We find that regularization is not necessary to prevent overfitting and that thresholding is an effective and user-friendly way to perform feature selection. The proposed method avoids problems inherent in regularization-based approaches, comes with a set of well-interpretable parameters whose default configuration is shown to generalize well without the need for fine-tuning, and is applicable to spectra of different platforms. The R package IPPD implements the method and is available from the Bioconductor platform (http://bioconductor.fhcrc.org/help/bioc-views/devel/bioc/html/IPPD.html).
    Electronic ISSN: 1471-2105
    Topics: Biology , Computer Science
    Published by BioMed Central
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 90
    Publication Date: 2012-11-09
    Description: Background: Monosporascus cannonballus is the main causal agent of melon vine decline disease. Several studies have been carried out mainly focused on the study of the penetration of this pathogen into melon roots, the evaluation of symptoms severity on infected roots, and screening assays for breeding programs. However, a detailed molecular view on the early interaction between M. cannonballus and melon roots in either susceptible or resistant genotypes is lacking. In the present study, we used a melon oligo-based microarray to investigate the gene expression responses of two melon genotypes, Cucumis melo 'Piel de sapo' ('PS') and C. melo 'Pat 81', with contrasting resistance to the disease. This study was carried out at 1 and 3 days after infection (DPI) by M. cannonballus. Results: Our results indicate a dissimilar behavior of the susceptible vs. the resistant genotypes from 1 to 3 DPI. 'PS' responded with a more rapid infection response than 'Pat 81' at 1 DPI. At 3 DPI the total number of differentially expressed genes identified in 'PS' declined from 451 to 359, while the total number of differentially expressed transcripts in 'Pat 81' increased from 187 to 849. Several deregulated transcripts coded for components of Ca2+ and jasmonic acid (JA) signalling pathways, as well as for other proteins related to defence mechanisms. Transcriptional differences in the activation of the JA-mediated response in 'Pat 81' compared to 'PS' suggested that JA response might be partially responsible for their observed differences in resistance. Conclusions: As a result of this study we have identified for the first time a set of candidate genes involved in the root response to the infection of the pathogen causing melon vine decline. This information is useful for understanding the disease progression and resistance mechanisms few days after inoculation.
    Electronic ISSN: 1471-2164
    Topics: Biology
    Published by BioMed Central
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 91
    Publication Date: 2012-11-09
    Description: Background: [NiFe] hydrogenases are enzymes that catalyze the oxidation of hydrogen into protons and electrons, to use H2 as energy source, or the production of hydrogen through proton reduction, as an escape valve for the excess of reduction equivalents in anaerobic metabolism. Biosynthesis of [NiFe] hydrogenases is a complex process that occurs in the cytoplasm, where a number of auxiliary proteins are required to synthesize and insert the metal cofactors into the enzyme structural units. The endosymbiotic bacterium Rhizobium leguminosarum requires the products of eighteen genes (hupSLCDEFGHIJKhypABFCDEX) to synthesize an active hydrogenase. hupF and hupK genes are found only in hydrogenase clusters from bacteria expressing hydrogenase in the presence of oxygen. Results: HupF is a HypC paralogue with a similar predicted structure, except for the C-terminal domain present only in HupF. Deletion of hupF results in the inability to process the hydrogenase large subunit HupL, and also in reduced stability of this subunit when cells are exposed to high oxygen tensions. A DeltahupF mutant was fully complemented for hydrogenase activity by a C-terminal deletion derivative under symbiotic, ultra low-oxygen tensions, but only partial complementation was observed in free living cells under higher oxygen tensions (1% or 3%). Co-purification experiments using StrepTag-labelled HupF derivatives and mass spectrometry analysis indicate the existence of a major complex involving HupL and HupF, and a less abundant HupF-HupK complex. Conclusions: The results indicate that HupF has a dual role during hydrogenase biosynthesis: it is required for hydrogenase large subunit processing and it also acts as a chaperone to stabilize HupL when hydrogenase is synthesized in the presence of oxygen.
    Electronic ISSN: 1471-2180
    Topics: Biology
    Published by BioMed Central
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 92
    Publication Date: 2012-11-09
    Description: Background: Blood coagulation is an essential determinant of coronary artery disease (CAD). Soluble Endothelial Protein C Receptor (sEPCR) may be a biomarker of a hypercoagulable state. We prospectively investigated the relationship between plasma sEPCR levels and the risk of cardiovascular events (CVE). Methods: We measured baseline sEPCR levels in 1673 individuals with CAD (521 with acute coronary syndrome [ACS] and 1152 with stable angina pectoris [SAP]) from the AtheroGene cohort. During a median follow up of 3.7 years, 136 individuals had a CVE. In addition, 891 of these CAD patients were genotyped for the PROCR rs867186 (Ser219Gly) variant. Results: At baseline, sEPCR levels were similar in individuals with ACS and SAP (median: 111 vs. 115 ng/mL respectively; p=0.20). Increased sEPCR levels were found to be associated with several cardiovascular risk factors including gender (p=0.006), soluble Tissue Factor levels (p=0.0001), diabetes (p=0.0005), and factors reflecting impaired renal function such as creatinine and cystatin C (p
    Electronic ISSN: 1471-2350
    Topics: Biology , Medicine
    Published by BioMed Central
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 93
    Publication Date: 2012-11-09
    Description: Background: Fungal load quantification is a critical component of fungal community analyses. Limitation of current approaches for quantifying the fungal component in the human microbiome suggests the need for new broad-coverage techniques. Methods: We analyzed 2,085 18S rRNA gene sequences from the SILVA database for assay design. We generated and quantified plasmid standards using a qPCR-based approach. We evaluated assay coverage against 4,968 sequences and performed assay validation following the Minimum Information for Publication of Quantitative Real-Time PCR Experiments (MIQE) guidelines. Results: We designed FungiQuant, a TaqMan(R) qPCR assay targeting a 351 bp region in the fungal 18S rRNA gene. Our in silico analysis showed that FungiQuant is a perfect sequence match to 90.0% of the 2,617 fungal species analyzed. We showed that FungiQuant's is 100% sensitive and its amplification efficiencies ranged from 76.3% to 114.5%, with r2-values of 〉0.99 against the 69 fungal species tested. Additionally, FungiQuant inter- and intra-run coefficients of variance ranged from
    Electronic ISSN: 1471-2180
    Topics: Biology
    Published by BioMed Central
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 94
    Publication Date: 2012-11-09
    Description: Background: Hyperelastosis cutis is an inherited autosomal recessive connective tissue disorder. Affected horses are characterized by hyperextensible skin, scarring, and severe lesions along the back. The disorder is caused by a mutation in cyclophilin B. Results: The crystal structures of both wild-type and mutated (Gly6-〉Arg) horse cyclophilin B are presented. The mutation neither affects the overall fold of the enzyme nor impairs the catalytic site structure. Instead, it locally rearranges the flexible N-terminal end of the polypeptide chain and also makes it more rigid. Conclusions: Interactions of the mutated cyclophilin B with a set of endoplasmic reticulum-resident proteins must be affected.
    Electronic ISSN: 1756-0500
    Topics: Biology , Medicine
    Published by BioMed Central
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 95
    Publication Date: 2012-11-09
    Description: Background: In plants, a large family of calmodulin (CaM) and CaM-like (CML) proteins transduce the increase in cytosolic Ca2+ concentrations by binding to and altering the activities of target proteins, and thereby affecting the physiological responses to a vast array of stimuli. Here, transcript expression analysis of Cam and CML gene family members in rice (Oryza sativa L.) was extensively examined. Results: Cam and CML genes in rice exhibited differential expression patterns in tissues/organs. Under osmotic stress and salt stress, expression of OsCam1-1, OsCML4, 5, 8, and 11 was induced with different kinetics and magnitude. OsCML4 and 8 mRNA levels significantly increased by 3 h after treatment and remained elevated for at least 24 h while expression of OsCam1-1, OsCML5 and 11 was up-regulated as early as 1--3 h before rapidly returning to normal levels. Several cis-acting elements in response to abiotic stresses, including DREs (important promoter elements responsive to drought, high salt, and cold stress), were detected in the 5[prime] upstream regions of these genes. The observed induction of the GUS activity of transgenic rice plants via the OsCam1-1 promoter appeared to be biphasic and dependent on the severity of salt stress. Conclusions: Large OsCam and OsCML gene family members likely play differential roles as signal transducers in regulating various developmental processes and represent important nodes in the signal transduction and transcriptional regulation networks in abiotic stresss responses mediated by the complex Ca2+ signals in plants, which are rich in both spatial and temporal information.
    Electronic ISSN: 1756-0500
    Topics: Biology , Medicine
    Published by BioMed Central
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 96
    Publication Date: 2012-11-09
    Description: Background: Plant microRNAs (miRNAs) play key roles in the transcriptional responses to environmental stresses. However, the role of miRNAs in responses to insect herbivory has not been thoroughly explored. To identify herbivory-responsive miRNAs, we first identified conserved miRNAs in the ecological model plant Nicotiana attenuata whose interactions with herbivores have been well-characterized in both laboratory and field studies. Results: We identified 59 miRNAs from 36 families, and two endogenous trans-acting small interfering RNAs (tasiRNA) targeted by miRNAs. We characterized the response of the precursor and mature miRNAs to simulated attack from the specialist herbivore Manduca sexta by quantitative PCR analysis and used ir-aoc RNAi transformants, deficient in jasmonate biosynthesis, to identify jasmonate-dependent and -independent miRNA regulation. Expression analysis revealed that groups of miRNAs and tasiRNAs were specifically regulated by either mechanical wounding or wounding plus oral secretions from M. sexta larvae, and these small RNAs were accumulated in jasmonate-dependent or -independent manners. Moreover, cDNA microarray analysis indicated that the expression patterns of the corresponding target genes were correlated with the accumulation of miRNAs and tasiRNAs. Conclusions: We show that a group of miRNAs and tasiRNAs orchestrates the expression of target genes involved in N. attenuata's responses to herbivore attack.
    Electronic ISSN: 1471-2229
    Topics: Biology
    Published by BioMed Central
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 97
    Publication Date: 2012-11-09
    Description: Background: Estrogen receptors alpha (ER) are implicated in many types of female cancers, and are the common target for anti-cancer therapy using selective estrogen receptor modulators (SERMs, such as tamoxifen). However, cell-type specific and patient-to-patient variability in response to SERMs (from suppression to stimulation of cancer growth), as well as frequent emergence of drug resistance, represents a serious problem. The molecular processes behind mixed effects of SERMs remain poorly understood, and this strongly motivates application of systems approaches. In this work, we aimed to establish a mathematical model of ER-dependent gene expression to explore potential mechanisms underlying the variable actions of SERMs. Results: We developed an equilibrium model of ER binding with 17beta-estradiol, tamoxifen and DNA, and linked it to a simple ODE model of ER-induced gene expression. The model was parameterised on the broad range of literature available experimental data, and provided a plausible mechanistic explanation for the dual agonism/antagonism action of tamoxifen in the reference cell line used for model calibration. To extend our conclusions to other cell types we ran global sensitivity analysis and explored model behaviour in the wide range of biologically plausible parameter values, including those found in cancer cells. Our findings suggest that transcriptional response to tamoxifen is controlled in a complex non-linear way by several key parameters, including ER expression level, hormone concentration, amount of ER-responsive genes and the capacity of ER-tamoxifen complexes to stimulate transcription (e.g. by recruiting co-regulators of transcription). The model revealed non-monotonic dependence of ER-induced transcriptional response on the expression level of ER, that was confirmed experimentally in four variants of the MCF-7 breast cancer cell line. Conclusions: We established a minimal mechanistic model of ER-dependent gene expression, that predicts complex non-linear effects in transcriptional response to tamoxifen in the broad range of biologically plausible parameter values. Our findings suggest that the outcome of a SERM's action is defined by several key components of cellular micro-environment, that may contribute to cell-type-specific effects of SERMs and justify the need for the development of combinatorial biomarkers for more accurate prediction of the efficacy of SERMs in specific cell types.
    Electronic ISSN: 1752-0509
    Topics: Biology
    Published by BioMed Central
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 98
    Publication Date: 2012-11-09
    Description: Publication year: 2012 Source: Cell Reports Hong Zan, Clayton A. White, Lisa M. Thomas, Thach Mai, Guideng Li, Zhenming Xu, Jinsong Zhang, Paolo Casali By diversifying the biological effector functions of antibodies, class switch DNA recombination (CSR) plays a critical role in the maturation of the immune response. It is initiated by activation-induced cytidine deaminase (AID)-mediated deoxycytosine deamination, yielding deoxyuridine (dU), and dU glycosylation by uracil DNA glycosylase (Ung) in antibody switch (S) region DNA. Here we showed that the translesion DNA synthesis polymerase Rev1 directly interacted with Ung and targeted in an AID-dependent and Ung-independent fashion the S regions undergoing CSR. Rev1 −/− Ung +/+ B cells reduced Ung recruitment to S regions, DNA-dU glycosylation, and CSR. Together with an S region spectrum of mutations similar to that of Rev1 +/+ Ung −/− B cells, this suggests that Rev1 operates in the same pathway as Ung, as emphasized by further decreased CSR in Rev1 −/− Msh2 −/− B cells. Rescue of CSR in Rev1 −/− B cells by a catalytically inactive Rev1 mutant shows that the important role of Rev1 in CSR is mediated by Rev1’s scaffolding function, not its enzymatic function. Graphical abstract Graphical Abstract Highlights ► Rev1 DNA polymerase plays an important role in class switch DNA recombination ► This role is mediated by Rev1’s scaffolding function, not its enzymatic function ► Rev1 interacts with Ung and recruits it to switch region DNA ► Rev1 enhances Ung-mediated dU glycosylation in DNA
    Electronic ISSN: 2211-1247
    Topics: Biology
    Published by Elsevier on behalf of Cell Press.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 99
    Publication Date: 2012-11-09
    Description: Publication year: 2012 Source: Cell Reports Michihiko Sugimoto, Masayo Kondo, Michiko Hirose, Misao Suzuki, Kazuyuki Mekada, Takaya Abe, Hiroshi Kiyonari, Atsuo Ogura, Nobuo Takagi, Karen Artzt, Kuniya Abe After implantation, pluripotent epiblasts are converted to embryonic ectoderm through cell–cell interactions that significantly change the transcriptional and epigenetic networks. An entrée to understanding this vital developmental transition is the t w5 mutation of the mouse t complex. This mutation produces highly specific defects in the embryonic ectoderm before gastrulation, leading to death of the embryonic ectoderm. Using a positional cloning approach, we have now identified the mutated gene, completing a decades-long search. The gene, vacuolar protein sorting 52 ( Vps52 ), is a mouse homolog of yeast VPS52 that is involved in the retrograde trafficking of endosomes. Our data suggest that Vps52 acts in extraembryonic tissues to support the growth and differentiation of embryonic ectoderm via cell–cell interactions. It is also required in the formation of embryonic structures at a later stage of development, revealing hitherto unknown functions of Vps52 in the development of a multicellular organism. Graphical abstract Graphical Abstract Highlights ► Vps52 , part of retrograde transport to the Golgi, causes the t w5 lethal phenotype ► Vps52 acts in extraembryonic tissues to dictate embryonic ectoderm differentiation ► VPS52’s essential function in the embryo involves cell–cell interactions ► VPS52 also has an indispensable function later in development
    Electronic ISSN: 2211-1247
    Topics: Biology
    Published by Elsevier on behalf of Cell Press.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 100
    Publication Date: 2012-11-09
    Description: Publication year: 2012 Source: Cell Reports Myrto Denaxa, Melanie Kalaitzidou, Anna Garefalaki, Angeliki Achimastou, Reena Lasrado, Tamara Maes, Vassilis Pachnis The generation of cortical interneuron subtypes is controlled by genetic programs that are activated in the ventral forebrain and unfold during the prolonged period of inhibitory neuron development. The LIM-homeodomain protein LHX6 is critical for the development of all cortical interneurons originating in the medial ganglionic eminence, but the molecular mechanisms that operate downstream of LHX6 to control the terminal differentiation of somatostatin- and parvalbumin-expressing interneurons within the cortex remain unknown. Here, we provide evidence that the nuclear matrix and genome organizer protein SATB1 is induced by neuronal activity and functions downstream of Lhx6 to control the transition of tangentially migrating immature interneurons into the terminally differentiated Somatostatin (SST)-expressing subtype. Our experiments provide a molecular framework for understanding the genetic and epigenetic mechanisms by which specified but immature cortical interneurons acquire the subtype-defining molecular and morphophysiological characteristics that allow them to integrate and function within cortical circuits. Graphical abstract Graphical Abstract Highlights ► Satb1 is specifically expressed in MGE-derived cortical interneurons ► Satb1 is required for the maturation of MGE-derived cortical interneurons in vivo ► Satb1 promotes the maturation of SST+ cortical interneurons downstream of Lhx6 ► Neuronal activity induces expression of Satb1 in immature cortical interneurons
    Electronic ISSN: 2211-1247
    Topics: Biology
    Published by Elsevier on behalf of Cell Press.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...