Role of Symbiotic Auxotrophy in the Rhizobium-Legume Symbioses

Symbiotic auxotrophy occurs in both determinate pea and indeterminate bean nodules demonstrating its importance for bacteroid formation and nodule function in legumes with different developmental programmes. However, only small quantities of branched chain amino acids are needed and symbiotic auxotrophy did not occur in the Sinorhizobium meliloti-alfalfa symbiosis under the conditions measured. The contrasting symbiotic phenotypes of aap bra mutants inoculated on different legumes probably reflects altered timing of amino acid availability, development of symbiotic auxotrophy and nodule developmental programmes

Combined vertebral fracture assessment and bone mineral density measurement: a new standard in the diagnosis of osteoporosis in academic populations

Vertebral Fracture Analysis enables the detection of vertebral fractures in the same session as bone mineral density testing. Using this method in 2,424 patients, we found unknown vertebral fractures in approximately one out of each six patients with significant impact on management. The presence of osteoporotic vertebral fractures (VF) is an important risk factor for all future fractures independent of BMD. Yet, determination of the VF status has not become standard practice. Vertebral Fracture Assessment (VFA) is a new feature available on modern densitometers. In this study we aimed to determine the prevalence of VF using VFA in all patients referred for BMD testing in a university medical center and to evaluate its added clinical value. Prospective diagnostic evaluation study in 2,500 consecutive patients referred for BMD. Patients underwent VFA in supine position after BMD testing. Questionnaires were used to assess perceived added value of VFA. In 2,424 patients (1,573 women), results were evaluable. In 541 patients (22%), VFA detected a prevalent VF that was unknown in 69%. In women, the prevalence was 20% versus 27% found in men (p <0.0001). The prevalence of VF was 14% in patients with normal BMD (97/678), increased to 21% (229/1,100) in osteopenia and to 26% in those with osteoporosis (215/646) by WHO criteria. After excluding mild fractures VF prevalence was 13% (322/2,424). In 468 of 942 questionnaires (50% response rate), 27% of the referring physicians reported VFA results to impact on patient management. VFA is a patient friendly new tool with a high diagnostic yield, as it detected unknown VF in one out of each six patients, with significant impact on management. We believe these findings justify considering VFA in all new patients referred for osteoporosis assessment in similar populations

Association of Health Literacy with Complementary and Alternative Medicine Use: A Cross-Sectional Study in Adult Primary Care Patients

<p>Abstract</p> <p>Background</p> <p>In the United States, it is estimated that 40% of adults utilize complementary and alternative medicine (CAM) therapies. Recently, national surveys report that over 90 million adults have inadequate health literacy. To date, no study has assessed health literacy and its effect on CAM use. The primary objective of this study was to assess the relationship between health literacy and CAM use independent of educational attainment. Second objective was to evaluate the differential effect of health literacy on CAM use by race.</p> <p>Methods</p> <p>351 patients were recruited from an outpatient primary care clinic. Validated surveys assessed CAM use (I-CAM-Q), health literacy (REALM-R), and demographic information. We compared demographics by health literacy (adequate vs. inadequate) and overall and individual CAM categories by health literacy using chi square statistics. We found a race by health literacy interaction and ran sequential logistic regression models stratified by race to test the association between health literacy and overall CAM use (Model 1), Model 1 + education (Model 2), and Model 2 + other demographic characteristics (Model 3). We reported the adjusted effect of health literacy on CAM use for both whites and African Americans separately.</p> <p>Results</p> <p>75% of the participants had adequate literacy and 80% used CAM. CAM use differed by CAM category. Among whites, adequate health literacy was significantly associated with increased CAM use in both unadjusted (Model 1, OR 7.68; p = 0.001) and models adjusted for education (Model 2, OR 7.70; p = 0.002) and other sociodemographics (Model 3, OR 9.42; p = 0.01). Among African Americans, adequate health literacy was not associated with CAM use in any of the models.</p> <p>Conclusions</p> <p>We found a race by literacy interaction suggesting that the relationship between health literacy and CAM use differed significantly by race. Adequate health literacy among whites is associated with increased CAM use, but not associated with CAM use in African Americans.</p

FITBAR: a web tool for the robust prediction of prokaryotic regulons

<p>Abstract</p> <p>Background</p> <p>The binding of regulatory proteins to their specific DNA targets determines the accurate expression of the neighboring genes. The <it>in silico </it>prediction of new binding sites in completely sequenced genomes is a key aspect in the deeper understanding of gene regulatory networks. Several algorithms have been described to discriminate against false-positives in the prediction of new binding targets; however none of them has been implemented so far to assist the detection of binding sites at the genomic scale.</p> <p>Results</p> <p>FITBAR (Fast Investigation Tool for Bacterial and Archaeal Regulons) is a web service designed to identify new protein binding sites on fully sequenced prokaryotic genomes. This tool consists in a workbench where the significance of the predictions can be compared using different statistical methods, a feature not found in existing resources. The Local Markov Model and the Compound Importance Sampling algorithms have been implemented to compute the P-value of newly discovered binding sites. In addition, FITBAR provides two optimized genomic scanning algorithms using either log-odds or entropy-weighted position-specific scoring matrices. Other significant features include the production of a detailed genomic context map for each detected binding site and the export of the search results in spreadsheet and portable document formats. FITBAR discovery of a high affinity <it>Escherichia coli </it>NagC binding site was validated experimentally <it>in vitro </it>as well as <it>in vivo </it>and published.</p> <p>Conclusions</p> <p>FITBAR was developed in order to allow fast, accurate and statistically robust predictions of prokaryotic regulons. This feature constitutes the main advantage of this web tool over other matrix search programs and does not impair its performance. The web service is available at <url>http://archaea.u-psud.fr/fitbar</url>.</p

An ethnographic study of Latino preschool children's oral health in rural California: Intersections among family, community, provider and regulatory sectors

<p>Abstract</p> <p>Background</p> <p>Latino children experience a higher prevalence of caries than do children in any other racial/ethnic group in the US. This paper examines the intersections among four societal sectors or contexts of care which contribute to oral health disparities for low-income, preschool Latino¹children in rural California.</p> <p>Methods</p> <p>Findings are reported from an ethnographic investigation, conducted in 2005–2006, of family, community, professional/dental and policy/regulatory sectors or contexts of care that play central roles in creating or sustaining low income, rural children's poor oral health status. The study community of around 9,000 people, predominantly of Mexican-American origin, was located in California's agricultural Central Valley. Observations in homes, community facilities, and dental offices within the region were supplemented by in-depth interviews with 30 key informants (such as dental professionals, health educators, child welfare agents, clinic administrators and regulatory agents) and 47 primary caregivers (mothers) of children at least one of whom was under 6 years of age.</p> <p>Results</p> <p>Caregivers did not always recognize visible signs of caries among their children, nor respond quickly unless children also complained of pain. Fluctuating seasonal eligibility for public health insurance intersected with limited community infrastructure and civic amenities, including lack of public transportation, to create difficulties in access to care. The non-fluoridated municipal water supply is not widely consumed because of fears about pesticide pollution. If the dentist brought children into the clinic for multiple visits, this caused the accompanying parent hardship and occasionally resulted in the loss of his or her job. Few general dentists had received specific training in how to handle young patients. Children's dental fear and poor provider-parent communication were exacerbated by a scarcity of dentists willing to serve rural low-income populations. Stringent state fiscal reimbursement policies further complicated the situation.</p> <p>Conclusion</p> <p>Several societal sectors or contexts of care significantly intersected to produce or sustain poor oral health care for children. Parental beliefs and practices, leading for example to delay in seeking care, were compounded by lack of key community or economic resources, and the organization and delivery of professional dental services. In the context of state-mandated policies and procedures, these all worked to militate against children receiving timely care that would considerably reduce oral health disparities among this highly disadvantaged population.</p

Osteopenia: A Diagnostic and Therapeutic Challenge

We discussed whether we are able to select a subgroup of patients with osteopenia having a high fracture risk, in which anti-osteoporotic drug treatment can be advocated. We concluded that in individuals in whom, based on clinical risk factors, a dual-energy x-ray absorptiometry (DXA) was performed in which osteopenia was diagnosed, anti-osteoporotic treatment should be prescribed in those patients with prevalent vertebral fractures, and in patients chronically using glucocorticoids, in a dosage of 7.5 mg per day or more. Although recent developments with regard to high-resolution imaging techniques (eg, peripheral quantitative computed tomography) seem to be promising, until now they do not provide substantial more reliable information than DXA in the prediction of fractures. We think that more data are urgently needed, since safe and effective drugs are available, but there is uncertainty to which patients with osteopenia these drugs should be prescribed

Assessment of clusters of transcription factor binding sites in relationship to human promoter, CpG islands and gene expression

BACKGROUND: Gene expression is regulated mainly by transcription factors (TFs) that interact with regulatory cis-elements on DNA sequences. To identify functional regulatory elements, computer searching can predict TF binding sites (TFBS) using position weight matrices (PWMs) that represent positional base frequencies of collected experimentally determined TFBS. A disadvantage of this approach is the large output of results for genomic DNA. One strategy to identify genuine TFBS is to utilize local concentrations of predicted TFBS. It is unclear whether there is a general tendency for TFBS to cluster at promoter regions, although this is the case for certain TFBS. Also unclear is the identification of TFs that have TFBS concentrated in promoters and to what level this occurs. This study hopes to answer some of these questions. RESULTS: We developed the cluster score measure to evaluate the correlation between predicted TFBS clusters and promoter sequences for each PWM. Non-promoter sequences were used as a control. Using the cluster score, we identified a PWM group called PWM-PCP, in which TFBS clusters positively correlate with promoters, and another PWM group called PWM-NCP, in which TFBS clusters negatively correlate with promoters. The PWM-PCP group comprises 47% of the 199 vertebrate PWMs, while the PWM-NCP group occupied 11 percent. After reducing the effect of CpG islands (CGI) against the clusters using partial correlation coefficients among three properties (promoter, CGI and predicted TFBS cluster), we identified two PWM groups including those strongly correlated with CGI and those not correlated with CGI. CONCLUSION: Not all PWMs predict TFBS correlated with human promoter sequences. Two main PWM groups were identified: (1) those that show TFBS clustered in promoters associated with CGI, and (2) those that show TFBS clustered in promoters independent of CGI. Assessment of PWM matches will allow more positive interpretation of TFBS in regulatory regions

What rheumatologists in the United States think of complementary and alternative medicine: results of a national survey

<p>Abstract</p> <p>Background</p> <p>We aimed to describe prevailing attitudes and practices of rheumatologists in the United States toward complementary and alternative medicine (CAM) treatments. We wanted to determine whether rheumatologists' perceptions of the efficacy of CAM therapies and their willingness to recommend them relate to their demographic characteristics, geographic location, or clinical practices.</p> <p>Methods</p> <p>A National Institutes of Health-sponsored cross-sectional survey of internists and rheumatologists was conducted regarding CAM for treatment of chronic back pain or joint pain. In this study we analyzed responses only from rheumatologists. Response items included participant characteristics and experience with 6 common CAM categories, as defined by the National Institutes of Health. Descriptive statistics were used to describe attitudes to CAM overall and to each CAM category. Composite responses were devised for respondents designating 4 or more of the 6 CAM therapies as "very" or "moderately" beneficial or "very likely" or "somewhat likely" to recommend.</p> <p>Results</p> <p>Of 600 rheumatologists who were sent the questionnaire, 345 responded (58%); 80 (23%) were women. Body work had the highest perceived benefit, with 70% of respondents indicating benefit. Acupuncture was perceived as beneficial by 54%. Most were willing to recommend most forms of CAM. Women had significantly higher composite benefit and recommend responses than men. Rheumatologists not born in North America were more likely to perceive benefit of select CAM therapies.</p> <p>Conclusions</p> <p>In this national survey of rheumatologists practicing in the United States, we found widespread favorable opinion toward many, but not all, types of CAM. Further research is required to determine to what extent CAM can or should be integrated into the practice of rheumatology in the United States.</p