Purification of Porphobilinogen Deaminase and the Sequencing and Expression of thehemC Gene of Rhodobacter Capsulatus.

Rhodobacter capsulatus uses the common tetrapyrrole pathway to synthesize heme, bacteriochlorophyll, siroheme and vitamin B-12. As part of our studies on the regulation of this pathway, the product of the hemC gene, porphobilinogen deaminase was purified approximately 200-fold. The molecular weight, isoelectric point, pH optimum and Km of the enzyme were all similar to other porphobilinogen deaminases. The stoichiometry of the enzyme was found not to be the expected four porphobilinogens used per one uroporphyrin formed. Rather a 9:1 ratio was typically seen. Further study of this atypical ratio uncovered evidence of possible in vivo regulation of porphobilinogen deaminase dependant on the cellular redox state. The protein was isolated from a two-dimensional gel and the sequence of the first twenty amino acids from the N-terminus was determined. This protein sequence matched a putative amino acid sequence 110 bp upstream of the R. capsulatus hemE gene. The putative hemC locus was subcloned from the plasmid pCAP154 which contains the R. capsulatus hemE gene with 1.2 Kb of upstream DNA. The sequence of the upstream DNA was determined by dideoxy sequencing of both strands. A single open reading frame of 951 bp was found which could code for a 317 amino acid protein of 34,082 Da. The putative protein has 49% identity with the E. coli porphobilinogen deaminase and 44% identity with the B. subtilis enzyme. When a plasmid carrying the R. capsulatus hemC was inserted into E. coli and R. capsulatus, a four-fold and ten-fold increase in porphobilinogen deaminase activity was seen respectively. The DNA sequence revealed that the hemC and hemE genes are divergently transcribed. A palindrome was identified between the two start sites, 47 bp upstream of hemE and 42 bp upstream of hemC. This palindrome, found upstream of many R. capsulatus genes, has been proposed to be a transcriptional regulatory site. The effects of oxygen on the transcription of hemC were studied using a hemC-cat fusion vector. Under the conditions tested, oxygen had no effect on the transcription of the R. capsulatus hemC gene

Normative Misperceptions about Alcohol Use in a General Population Sample of Problem Drinkers from a Large Metropolitan City

Aims: Heavy drinkers tend to overestimate how much others drink (normative fallacy), at least in college samples. Little research has been conducted to evaluate whether normative misperceptions about drinking extend beyond the college population. The present study explored normative misperceptions in an adult general population sample of drinkers. Methods: As part of a larger study, in Toronto, Canada, a random digit dialling telephone survey was conducted with 14,009 participants who drank alcohol at least once per month. Respondents with Alcohol Use Disorders Identification Test of eight or more (n = 2757) were asked to estimate what percent of Canadians of their same sex: (a) drank more than they do; (b) were abstinent and (c) drank seven or more drinks per week. Respondents' estimates of these population drinking norms were then compared with the actual levels of alcohol consumption in the Canadian population. Results: A substantial level of normative misperception was observed for estimates of levels of drinking in the general population. Estimates of the proportion of Canadians who were abstinent were fairly accurate. There was some evidence of a positive relationship between the respondents' own drinking severity and the extent of normative misperceptions. Little evidence was found of a relationship between degree of normative misperceptions and age. Conclusion: Normative misperceptions have been successfully targeted in social norms media campaigns as well as in personalized feedback interventions for problem drinkers. The present research solidifies the empirical bases for extending these interventions more widely into the general population

SHIRAZ: an automated histology image annotation system for zebrafish phenomics

Histological characterization is used in clinical and research contexts as a highly sensitive method for detecting the morphological features of disease and abnormal gene function. Histology has recently been accepted as a phenotyping method for the forthcoming Zebrafish Phenome Project, a large-scale community effort to characterize the morphological, physiological, and behavioral phenotypes resulting from the mutations in all known genes in the zebrafish genome. In support of this project, we present a novel content-based image retrieval system for the automated annotation of images containing histological abnormalities in the developing eye of the larval zebrafish

Co-bedding as a Comfort measure For Twins undergoing painful procedures (CComForT Trial)

<p>Abstract</p> <p>Background</p> <p>Co-bedding, a developmental care strategy, is the practice of caring for diaper clad twins in one incubator (versus separating and caring for each infant in separate incubators), thus creating the opportunity for skin-to-skin contact and touch between the twins. In studies of mothers and their infants, maternal skin-to-skin contact has been shown to decrease procedural pain response according to both behavioral and physiological indicators in very preterm neonates. It is uncertain if this comfort is derived solely from maternal presence or from stabilization of regulatory processes from direct skin contact. The intent of this study is to compare the comfort effect of co-bedding (between twin infants who are co-bedding and those who are not) on infant pain response and physiologic stability during a tissue breaking procedure (heelstick).</p> <p>Methods/Design</p> <p>Medically stable preterm twin infants admitted to the Neonatal Intensive Care Unit will be randomly assigned to a co-bedding group or a standard care group. Pain response will be measured by physiological and videotaped facial reaction using the Premature Infant Pain Profile scale (PIPP). Recovery from the tissue breaking procedure will be determined by the length of time for heart rate and oxygen saturation to return to baseline. Sixty four sets of twins (n = 128) will be recruited into the study. Analysis and inference will be based on the intention-to-treat principle.</p> <p>Discussion</p> <p>If twin contact while co-bedding is determined to have a comforting effect for painful procedures, then changes in current neonatal care practices to include co-bedding may be an inexpensive, non invasive method to help maintain physiologic stability and decrease the long term psychological impact of procedural pain in this high risk population. Knowledge obtained from this study will also add to existing theoretical models with respect to the exact mechanism of comfort through touch.</p> <p>Trial registration</p> <p>NCT00917631</p

The role of UDP-Glc:glycoprotein glucosyltransferase 1 in the maturation of an obligate substrate prosaposin

A natural substrate for UGT1 is confirmed, revealing how the enzyme functions in the calnexin chaperone system as a quality control step in protein folding

Defining the effect and mediators of two knowledge translation strategies designed to alter knowledge, intent and clinical utilization of rehabilitation outcome measures: a study protocol [NCT00298727]

BACKGROUND: A substantial number of valid outcome measures have been developed to measure health in adult musculoskeletal and childhood disability. Regrettably, national initiatives have merely resulted in changes in attitude, while utilization remains unacceptably low. This study will compare the effectiveness and mediators of two different knowledge transfer (KT) interventions in terms of their impact on changing knowledge and behavior (utilization and clinical reasoning) related to health outcome measures. METHOD/DESIGN: Physical and occupational therapists (n = 144) will be recruited in partnership with the national professional associations to evaluate two different KT interventions with the same curriculum: 1) Stakeholder-Hosted Interactive Problem-Based Seminar (SHIPS), and 2) Online Problem-Based course (e-PBL). SHIPS will consist of face-to-face problem-based learning (PBL) for 2 1/2 days with outcome measure developers as facilitators, using six problems generated in consultation with participants. The e-PBL will consist of a 6-week web-based course with six generic problems developed by content experts. SHIPS will be conducted in three urban centers in Canada. Participants will be block-allocated by a minimization procedure to either of the two interventions to minimize any prognostic differences. Trained evaluators at each site will conduct chart audits and chart-stimulated recall. Trained interviewers will conduct semi-structured interviews focused on identifying critical elements in KT and implementing practice changes. Interviews will be transcribed verbatim. Baseline predictors including demographics, knowledge, attitudes/barriers regarding outcome measures, and Readiness to Change will be assessed by self-report. Immediately post-intervention and 6 months later, these will be re-administered. Primary qualitative and quantitative evaluations will be conducted 6-months post-intervention to assess the relative effectiveness of KT interventions and to identify elements that contribute to changing clinical behavior. Chart audits will determine the utilization of outcome measures (counts). Incorporation of outcome measures into clinical reasoning will be assessed using an innovative technique: chart-stimulated recall. DISCUSSION: A strategy for optimal transfer of health outcome measures into practice will be developed and shared with multiple disciplines involved in primary and specialty management of musculoskeletal and childhood disability

Ultra-brief intervention for problem drinkers: research protocol

Background: Helping the large number of problem drinkers who will never seek treatment is a challenging issue. Public health initiatives employing educational materials or mass media campaigns have met with mixed success. However, clinical research has developed effective brief interventions to help problem drinkers. This project will employ an intervention that has been validated in clinical settings and then modified into an ultra-brief format suitable for use as a public health intervention. The major objective of this study is to conduct a randomized controlled trial to establish the effectiveness of an ultra-brief, personalized feedback intervention for problem drinkers. Methods/design: Problem drinkers recruited on a baseline population telephone survey conducted in a major metropolitan city in Canada will be randomized to one of three conditions - a personalized feedback pamphlet condition, a control pamphlet condition, or a no intervention control condition. In the week after the baseline survey, households in the two pamphlet conditions will be sent their respective pamphlets. Changes in drinking will be assessed post intervention at three-month and six-month follow-ups. Drinking outcomes will be compared between experimental conditions using Structural Equation Modeling. The primary hypothesis is that problem drinkers from households who receive the personalized feedback pamphlet intervention will display significantly improved drinking outcomes at three and six-month follow-ups as compared to problem drinkers from households in the no intervention control condition. Secondary hypotheses will test the impact of the intervention on help seeking, and explore the mediating or moderating role of perceived drinking norms, perceived alcohol risks and the problem drinker's social reasons for drinking. Discussion: This trial will provide information on the effectiveness of a pamphlet-based personalized feedback intervention for problem drinkers in a community setting. Trial registration: ClinicalTrials.gov registration #NCT00688584.This study is funded by the National Institute on Alcohol Abuse and Alcoholism (NIAAA). Grant #R01 AA015680-01A2