Transcriptional and pathway analysis in the hypothalamus of newly hatched chicks during fasting and delayed feeding

<p>Abstract</p> <p>Background</p> <p>The hypothalamus plays a central role in regulating appetite and metabolism. However, the gene networks within the hypothalamus that regulate feed intake and metabolism, and the effects of fasting on those pathways are not completely understood in any species. The present experiment evaluated global hypothalamic gene expression in newly hatched chicks using microarray analysis to elucidate genes and pathways regulated by feeding, fasting, and delayed feeding. Ten groups of chicks were sampled over four days post-hatch, including fed, fasted, and 48 h fasted followed by access to feed for 4 h, 24 h, and 48 h. Hypothalamic samples were collected for microarray analysis (n = 4). Expression patterns of selected genes were confirmed by quantitative real-time PCR. Pathway analysis of the microarray results predicted a network of genes involved in neuropeptide or neurotransmitter signaling. To confirm the functionality of this predicted gene network, hypothalamic neurons from fed and fasted chicks were isolated and cultured in the presence of neuropeptide Y, somatostatin, α-melanocyte stimulating hormone, norepinephrine, and L-phospho-serine. Results confirmed functional relationships among members of the predicted gene network. Moreover, the effects observed were dependant upon the nutritional state of the animals (fed <it>vs</it>. fasted).</p> <p>Results</p> <p>Differences in gene expression (≥ 1.6 fold) were detected in 1,272 genes between treatments, and of those, 119 genes were significantly (P < 0.05) different. Pathway Miner analysis revealed that six genes (<it>SSTR5</it>, <it>NPY5R</it>, <it>POMC</it>, <it>ADRB2</it>, <it>GRM8</it>, and <it>RLN3</it>) were associated within a gene network. <it>In vitro </it>experiments with primary hypothalamic neurons confirmed that receptor agonists involved in this network regulated expression of other genes in the predicted network, and this regulation within the network was influenced by the nutritional status and age of the chick.</p> <p>Conclusions</p> <p>Microarray analysis of the hypothalamus during different nutritional states revealed that many genes are differentially regulated. We found that functional interactions exist among six differentially regulated genes associated within a putative gene network from this experiment. Considering that <it>POMC</it>, an important gene in controlling metabolism, was central to this network, this gene network may play an important role in regulation of feeding and metabolism in birds.</p

Method for bacteriophage delivery and amplification

Methods of selecting wide host range bacteriophage capable of growing in a plurality of bacteria including pathogenic and non-pathogenic bacteria and bacteriophage selected by the methods are disclosed. Also disclosed are: methods of treating a subject infected with a pathogenic bacterium using bacteriophage, of decontaminating objects using bacteriophage, and of producing vaccines. In another aspect, methods of determining bacterial viability and of improving the sensitivity of a biosensor using wide host range bacteriophages are also disclosed

Method for Bacteriophage Delivery and Amplification

Methods of selecting wide host range bacteriophage capable of growing in a plurality of bacteria including pathogenic and non-pathogenic bacteria and bacteriophage selected are described. In addition to methods of treating a subject infected with a pathogenic bacterium using bacteriophage, of decontaminating objects using bacteriophage, of producing vaccines. In another aspect, methods of determining bacterial viability and methods of improving the sensitivity of a biosensor using wide host range bacteriophages are also disclosed

Wide Distribution of O157-Antigen Biosynthesis Gene Clusters in Escherichia coli

Most Escherichia coli O157-serogroup strains are classified as enterohemorrhagic E. coli (EHEC), which is known as an important food-borne pathogen for humans. They usually produce Shiga toxin (Stx) 1 and/or Stx2, and express H7-flagella antigen (or nonmotile). However, O157 strains that do not produce Stxs and express H antigens different from H7 are sometimes isolated from clinical and other sources. Multilocus sequence analysis revealed that these 21 O157:non-H7 strains tested in this study belong to multiple evolutionary lineages different from that of EHEC O157:H7 strains, suggesting a wide distribution of the gene set encoding the O157-antigen biosynthesis in multiple lineages. To gain insight into the gene organization and the sequence similarity of the O157-antigen biosynthesis gene clusters, we conducted genomic comparisons of the chromosomal regions (about 59 kb in each strain) covering the O-antigen gene cluster and its flanking regions between six O157:H7/non-H7 strains. Gene organization of the O157-antigen gene cluster was identical among O157:H7/non-H7 strains, but was divided into two distinct types at the nucleotide sequence level. Interestingly, distribution of the two types did not clearly follow the evolutionary lineages of the strains, suggesting that horizontal gene transfer of both types of O157-antigen gene clusters has occurred independently among E. coli strains. Additionally, detailed sequence comparison revealed that some positions of the repetitive extragenic palindromic (REP) sequences in the regions flanking the O-antigen gene clusters were coincident with possible recombination points. From these results, we conclude that the horizontal transfer of the O157-antigen gene clusters induced the emergence of multiple O157 lineages within E. coli and speculate that REP sequences may involve one of the driving forces for exchange and evolution of O-antigen loci

An Individual-Difference Perspective Applied to Word Association

Most cognitive approaches to word association and some theories of social cognition converge on the notion that the performance of repetitive behaviors should predict word association responses. To study this issue, the authors examined the frequencies of free-association responses of 1, 003 subjects to ambiguous words, some of which had subdominant senses that were linked to repetitive behaviors (e.g., draft and alcohol use). Results showed that three out of four measures of individual differences in repetitive behaviors significantly predicted responses for words linked to their respective behaviors. Gender, age, and language background were controlled for in these analyses. Although cognitive approaches suggested that an experimental manipulation of item presentation (grouped vs. randomly mixed items) should influence responses, this effect was not significant. Implications are discussed in terms of theories of lexical ambiguity and implicit influences of memory for previous experiences

Understanding how adherence goals promote adherence behaviours: a repeated measure observational study with HIV seropositive patients

Background The extent to which patients follow treatments as prescribed is pivotal to treatment success. An exceptionally high level (> 95 %) of HIV medication adherence is required to suppress viral replication and protect the immune system and a similarly high level (> 80 %) of adherence has also been suggested in order to benefit from prescribed exercise programmes. However, in clinical practice, adherence to both often falls below the desirable level. This project aims to investigate a wide range of psychological and personality factors that may lead to adherence/non-adherence to medical treatment and exercise programmes. Methods HIV positive patients who are referred to the physiotherapist-led 10-week exercise programme as part of the standard care are continuously recruited. Data on social cognitive variables (attitude, intention, subjective norms, self-efficacy, and outcome beliefs) about the goal and specific behaviours, selected personality factors, perceived quality of life, physical activity, self-reported adherence and physical assessment are collected at baseline, at the end of the exercise programme and again 3 months later. The project incorporates objective measures of both exercise (attendance log and improvement in physical measures such as improved fitness level, weight loss, improved circumferential anthropometric measures) and medication adherence (verified by non-invasive hair analysis). Discussion The novelty of this project comes from two key aspects, complemented with objective information on exercise and medication adherence. The project assesses beliefs about both the underlying goal such as following prescribed treatment; and about the specific behaviours such as undertaking the exercise or taking the medication, using both implicit and explicit assessments of patients' beliefs and attitudes. We predict that i) the way people think about the underlying goal of their treatments explains medication and exercise behaviours over and above the effects of the behaviour-specific thinking and ii) the relationship between adherence to exercise and to medical treatment is stronger among those with more favourable views about the goal. Results from this study should identify the key contributing factors to inform subsequent adherence research and afford a more streamlined assessment matrix. The project also aims to inform patient care practices. UK Clinical Research Network registration number: UKCRN 7842

Self-Generated Alcohol Outcome Expectancies in Four Samples of Drinkers

Research on beliefs about the expected effects of alcohol has suggested a major role for these expectancies in motivating drinking behavior. Measures developed to assess these expectancies, however, are likely to cue subject\u27s responses and may not represent the expected effects that are the most salient for an individual. Expected effects of alcohol were elicited by way of open-ended questionnaires from samples of college students, fraternity members, drunk drivers, and alcoholism treatment clients. The results yielded few sex differences, but large differences between male respondents in the different samples. It is suggested that this measurement technique may be useful in assessing those expectancies that are the most central in individual\u27s belief systems