Ghrelin causes hyperphagia and obesity in rats.

Ghrelin, a circulating growth hormone–releasing pep-tide derived from the stomach, stimulates food intake. The lowest systemically effective orexigenic dose of ghrelin was investigated and the resulting plasma ghre-lin concentration was compared with that during fast-ing. The lowest dose of ghrelin that produced a significant stimulation of feeding after intraperitoneal injection was 1 nmol. The plasma ghrelin concentration after intraperitoneal injection of 1 nmol of ghrelin (2.83 0.13 pmol/ml at 60 min postinjection) was not significantly different from that occurring after a 24-h fast (2.79 0.32 pmol/ml). After microinjection into defined hypothalamic sites, ghrelin (30 pmol) stimu-lated food intake most markedly in the arcuate nucleus (Arc) (0–1 h food intake, 427 43 % of control; P &lt

Transcriptional analysis of the bovine herpesvirus 1 Cooper isolate

Blot hybridization analysis of infected bovine herpesvirus 1 (BHV-1) cellular RNA isolated at various times post infection and after treatment with specific metabolic inhibitors was used to characterize transcription of the BHV-1 Cooper isolate. Synthesis of BHV-1 RNA was detected as early as 3 h post infection and reached a maximum at six to eight hours post infection. The most transcriptionally active area of the genome was between map units 0.110 to 0.195, within the Hin dIII I fragment. From the entire genome a total of 59 transcripts ranging in size from approximately 0.6 to 10 kilobases were characterized as belonging to one of three distinct classes. Using the protein synthesis inhibitor cycloheximide, three immediate-early transcripts were identified as originating from the internal inverted repeat region between map units 0.734 and 0.842, corresponding to the Hin dIII D fragment. Using phosphonoacetic acid to prevent virus DNA synthesis by inhibition of the BHV-1 DNA polymerase, 28 early transcripts were recognized. The remaining 28 transcripts, classified as late RNA, were detected without the use of metabolic inhibitors at 6 to 8 h post infection. Transcription of early and late RNA was not restricted to any specific area of the genome. Eighty percent of the transcripts from both the Hin dIII A fragment, between map units 0.381 to 0.537 within the unique long segment, and the Hin dIII K fragment, between map units 0.840 to 0.907 of the unique short segment, were designated as belonging to the early class.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/41672/1/705_2005_Article_BF01316744.pd

HIPPIE: Integrating Protein Interaction Networks with Experiment Based Quality Scores

Protein function is often modulated by protein-protein interactions (PPIs) and therefore defining the partners of a protein helps to understand its activity. PPIs can be detected through different experimental approaches and are collected in several expert curated databases. These databases are used by researchers interested in examining detailed information on particular proteins. In many analyses the reliability of the characterization of the interactions becomes important and it might be necessary to select sets of PPIs of different confidence levels. To this goal, we generated HIPPIE (Human Integrated Protein-Protein Interaction rEference), a human PPI dataset with a normalized scoring scheme that integrates multiple experimental PPI datasets. HIPPIE's scoring scheme has been optimized by human experts and a computer algorithm to reflect the amount and quality of evidence for a given PPI and we show that these scores correlate to the quality of the experimental characterization. The HIPPIE web tool (available at http://cbdm.mdc-berlin.de/tools/hippie) allows researchers to do network analyses focused on likely true PPI sets by generating subnetworks around proteins of interest at a specified confidence level

Comparative genomic analysis of toxin-negative strains of Clostridium difficile from humans and animals with symptoms of gastrointestinal disease

Background: Clostridium difficile infections (CDI) are a significant health problem to humans and food animals. Clostridial toxins ToxA and ToxB encoded by genes tcdA and tcdB are located on a pathogenicity locus known as the PaLoc and are the major virulence factors of C. difficile. While toxin-negative strains of C. difficile are often isolated from faeces of animals and patients suffering from CDI, they are not considered to play a role in disease. Toxin-negative strains of C. difficile have been used successfully to treat recurring CDI but their propensity to acquire the PaLoc via lateral gene transfer and express clinically relevant levels of toxins has reinforced the need to characterise them genetically. In addition, further studies that examine the pathogenic potential of toxin-negative strains of C. difficile and the frequency by which toxin-negative strains may acquire the PaLoc are needed. Results: We undertook a comparative genomic analysis of five Australian toxin-negative isolates of C. difficile that lack tcdA, tcdB and both binary toxin genes cdtA and cdtB that were recovered from humans and farm animals with symptoms of gastrointestinal disease. Our analyses show that the five C. difficile isolates cluster closely with virulent toxigenic strains of C. difficile belonging to the same sequence type (ST) and have virulence gene profiles akin to those in toxigenic strains. Furthermore, phage acquisition appears to have played a key role in the evolution of C. difficile. Conclusions: Our results are consistent with the C. difficile global population structure comprising six clades each containing both toxin-positive and toxin-negative strains. Our data also suggests that toxin-negative strains of C. difficile encode a repertoire of putative virulence factors that are similar to those found in toxigenic strains of C. difficile, raising the possibility that acquisition of PaLoc by toxin-negative strains poses a threat to human health. Studies in appropriate animal models are needed to examine the pathogenic potential of toxin-negative strains of C. difficile and to determine the frequency by which toxin-negative strains may acquire the PaLoc

Gene signatures of breast cancer progression and metastasis

Breast cancer is a heterogeneous disease. Patient outcome varies significantly, depending on prognostic features of patients and their tumors, including patient age, menopausal status, tumor size and histology, nodal status, and so on. Response to treatment also depends on a series of predictive factors, such as hormone receptor and HER2 status. Current treatment guidelines use these features to determine treatment. However, these guidelines are imperfect, and do not always predict response to treatment or survival. Evolving technologies are permitting increasingly large amounts of molecular data to be obtained from tumors, which may enable more personalized treatment decisions to be made. The challenge is to learn what information leads to improved prognostic accuracy and treatment outcome for individual patients

Endothelial Differentiation of Human Stem Cells Seeded onto Electrospun Polyhydroxybutyrate/Polyhydroxybutyrate-Co-Hydroxyvalerate Fiber Mesh

Tissue engineering is based on the association of cultured cells with structural matrices and the incorporation of signaling molecules for inducing tissue regeneration. Despite its enormous potential, tissue engineering faces a major challenge concerning the maintenance of cell viability after the implantation of the constructs. The lack of a functional vasculature within the implant compromises the delivery of nutrients to and removal of metabolites from the cells, which can lead to implant failure. In this sense, our investigation aims to develop a new strategy for enhancing vascularization in tissue engineering constructs. This study's aim was to establish a culture of human adipose tissue-derived stem cells (hASCs) to evaluate the biocompatibility of electrospun fiber mesh made of polyhydroxybutyrate (PHB) and its copolymer poly-3-hydroxybutyrate-co-3-hydroxyvalerate (PHB-HV) and to promote the differentiation of hASCs into the endothelial lineage. Fiber mesh was produced by blending 30% PHB with 70% PHB-HV and its physical characterization was conducted using scanning electron microscopy analysis (SEM). Using electrospinning, fiber mesh was obtained with diameters ranging 300 nm to 1.3 µm. To assess the biological performance, hASCs were extracted, cultured, characterized by flow cytometry, expanded and seeded onto electrospun PHB/PHB-HV fiber mesh. Various aspects of the cells were analyzed in vitro using SEM, MTT assay and Calcein-AM staining. The in vitro evaluation demonstrated good adhesion and a normal morphology of the hASCs. After 7, 14 and 21 days of seeding hASCs onto electrospun PHB/PHB-HV fiber mesh, the cells remained viable and proliferative. Moreover, when cultured with endothelial differentiation medium (i.e., medium containing VEGF and bFGF), the hASCs expressed endothelial markers such as VE-Cadherin and the vWF factor. Therefore, the electrospun PHB/PHB-HV fiber mesh appears to be a suitable material that can be used in combination with endothelial-differentiated cells to improve vascularization in engineered bone tissues

The effect of vitamin B12 and folic acid supplementation on routine haematological parameters in older people: an individual participant data meta-analysis.

BACKGROUND/OBJECTIVES: Low vitamin B12 and folate levels in community-dwelling older people are usually corrected with supplements. However, the effect of this supplementation on haematological parameters in older persons is not known. Therefore, we executed a systematic review and individual participant data meta-analysis of randomised placebo-controlled trials (RCTs). SUBJECTS/METHODS: We performed a systematic search in PubMed, EMBASE, Web of Science, Cochrane and CENTRAL for RCTs published between January 1950 and April 2016, where community-dwelling elderly (60+ years) who were treated with vitamin B12 or folic acid or placebo. The presence of anaemia was not required. We analysed the data on haematological parameters with a two-stage IPD meta-analysis. RESULTS: We found 494 full papers covering 14 studies. Data were shared by the authors of four RCTs comparing vitamin B12 with placebo (n = 343) and of three RCTs comparing folic acid with placebo (n = 929). We found no effect of vitamin B12 supplementation on haemoglobin (change 0.00 g/dL, 95% CI: -0.19;0.18), and no effect of folic acid supplementation (change -0.09 g/dL, 95% CI: -0.19;0.01). The effects of supplementation on other haematological parameters were similar. The effects did not differ by sex or by age group. Also, no effect was found in a subgroup of patients with anaemia and a subgroup of patients who were treated >4 weeks. CONCLUSIONS: Evidence on the effects of supplementation of low concentrations of vitamin B12 and folate on haematological parameters in community-dwelling older people is inconclusive. Further research is needed before firm recommendations can be made concerning the supplementation of vitamin B12 and folate