Genomic Islands Confer Heavy Metal Resistance in <i>Mucilaginibacter kameinonensis</i> and <i>Mucilaginibacter rubeus</i> Isolated from a Gold/Copper Mine.

Heavy metals (HMs) are compounds that can be hazardous and impair growth of living organisms. Bacteria have evolved the capability not only to cope with heavy metals but also to detoxify polluted environments. Three heavy metal-resistant strains of &lt;i&gt;Mucilaginibacer rubeus&lt;/i&gt; and one of &lt;i&gt;Mucilaginibacter kameinonensis&lt;/i&gt; were isolated from the gold/copper Zijin mining site, Longyan, Fujian, China. These strains were shown to exhibit high resistance to heavy metals with minimal inhibitory concentration reaching up to 3.5 mM Cu &lt;sup&gt;(II)&lt;/sup&gt; , 21 mM Zn &lt;sup&gt;(II)&lt;/sup&gt; , 1.2 mM Cd &lt;sup&gt;(II)&lt;/sup&gt; , and 10.0 mM As &lt;sup&gt;(III)&lt;/sup&gt; . Genomes of the four strains were sequenced by Illumina. Sequence analyses revealed the presence of a high abundance of heavy metal resistance (HMR) determinants. One of the strain, &lt;i&gt;M. rubeus&lt;/i&gt; P2, carried genes encoding 6 putative P &lt;sub&gt;IB-1&lt;/sub&gt; -ATPase, 5 putative P &lt;sub&gt;IB-3&lt;/sub&gt; -ATPase, 4 putative Zn &lt;sup&gt;(II)&lt;/sup&gt; /Cd &lt;sup&gt;(II)&lt;/sup&gt; P &lt;sub&gt;IB-4&lt;/sub&gt; type ATPase, and 16 putative resistance-nodulation-division (RND)-type metal transporter systems. Moreover, the four genomes contained a high abundance of genes coding for putative metal binding chaperones. Analysis of the close vicinity of these HMR determinants uncovered the presence of clusters of genes potentially associated with mobile genetic elements. These loci included genes coding for tyrosine recombinases (integrases) and subunits of mating pore (type 4 secretion system), respectively allowing integration/excision and conjugative transfer of numerous genomic islands. Further in silico analyses revealed that their genetic organization and gene products resemble the &lt;i&gt;Bacteroides&lt;/i&gt; integrative and conjugative element CTnDOT. These results highlight the pivotal role of genomic islands in the acquisition and dissemination of adaptive traits, allowing for rapid adaption of bacteria and colonization of hostile environments

Self-perceived physical health predicts cardiovascular disease incidence and death among postmenopausal women

Background: Physical and Mental Component Summary (PCS, MCS, respectively) scales of SF- 36 health-related-quality-of-life have been associated with all-cause and cardiovascular disease (CVD) mortality. Their relationships with CVD incidence are unclear. This study purpose was to test whether PCS and/or MCS were associated with CVD incidence and death. Methods. Postmenopausal women (aged 50-79 years) in control groups of the Women's Health Initiative clinical trials (n = 20,308) completed the SF-36 and standardized questionnaires at trial entry. Health outcomes, assessed semi-annually, were verified with medical records. Cox regressions assessed time to selected outcomes during the trial phase (1993-2005). Results: A total of 1075 incident CVD events, 204 CVD-specific deaths, and 1043 total deaths occurred during the trial phase. Women with low versus high baseline PCS scores had less favorable health profiles at baseline. In multivariable models adjusting for baseline confounders, participants in the lowest PCS quintile (reference = highest quintile) exhibited 1.8 (95%CI: 1.4, 2.3), 4.7 (95%CI: 2.3, 9.4), and 2.1 (95%CI: 1.7, 2.7) times greater risk of CVD incidence, CVD-specific death, and total mortality, respectively, by trial end; whereas, MCS was not significantly associated with CVD incidence or death. Conclusion: Physical health, assessed by self-report of physical functioning, is a strong predictor of CVD incidence and death in postmenopausal women; similar self-assessment of mental health is not. PCS should be evaluated as a screening tool to identify older women at high risk for CVD development and death. © 2013 Saquib et al.; licensee BioMed Central Ltd

Prediction of crack depth and fatigue life of an acrylonitrile butadiene styrene cantilever beam using dynamic response

n this article, a methodology is proposed that can be used to predict the crack growth and fatigue life of a cantilever beam made of Acrylonitrile Butadiene Styrene (ABS) manufactured with fused deposition modeling. Three beam configurations based on length (L = 110, 130, and 150 mm) are considered. Empirical relationships are formulated between the natural frequency and the crack growth. The analytical and experimental results are found to be in good agreement for all configurations. Using the experimental data, a global relation is formulated for the crack depth prediction. This global relation is useful for an in situ crack depth prediction with an error of less than 10 %. Later, a residual fatigue life of these specimens is compared with a metallic structure (Aluminum 1050) of similar configuration available in the literature. It is found that the ABS material has more residual fatigue life compared with the metallic structure at the same frequency drop. Based on the remaining fatigue life, ABS material can be a potential material to manufacture machine components under cyclic loads

Bacterial resistance to arsenic protects against protist killing

Protists kill their bacterial prey using toxic metals such as copper. Here we hypothesize that the metalloid arsenic has a similar role. To test this hypothesis, we examined intracellular survival of Escherichia coli (E. coli) in the amoeba Dictyostelium discoideum (D. discoideum). Deletion of the E. coli ars operon led to significantly lower intracellular survival compared to wild type E. coli. This suggests that protists use arsenic to poison bacterial cells in the phagosome, similar to their use of copper. In response to copper and arsenic poisoning by protists, there is selection for acquisition of arsenic and copper resistance genes in the bacterial prey to avoid killing. In agreement with this hypothesis, both copper and arsenic resistance determinants are widespread in many bacterial taxa and environments, and they are often found together on plasmids. A role for heavy metals and arsenic in the ancient predator–prey relationship between protists and bacteria could explain the widespread presence of metal resistance determinants in pristine environments

Bayesian Inference in Processing Experimental Data: Principles and Basic Applications

This report introduces general ideas and some basic methods of the Bayesian probability theory applied to physics measurements. Our aim is to make the reader familiar, through examples rather than rigorous formalism, with concepts such as: model comparison (including the automatic Ockham's Razor filter provided by the Bayesian approach); parametric inference; quantification of the uncertainty about the value of physical quantities, also taking into account systematic effects; role of marginalization; posterior characterization; predictive distributions; hierarchical modelling and hyperparameters; Gaussian approximation of the posterior and recovery of conventional methods, especially maximum likelihood and chi-square fits under well defined conditions; conjugate priors, transformation invariance and maximum entropy motivated priors; Monte Carlo estimates of expectation, including a short introduction to Markov Chain Monte Carlo methods.Comment: 40 pages, 2 figures, invited paper for Reports on Progress in Physic

Age at Menarche, the Leg Length to Sitting Height Ratio, and Risk of Diabetes in Middle-Aged and Elderly Chinese Men and Women

To evaluate the associations of age at menarche and the leg length-to-sitting-height ratio, markers of adolescent growth, with risk of diabetes in later life.Information from 69,385 women and 55,311 men, aged 40-74 years from the Shanghai Women's Health Study and Shanghai Men's Health Study, were included in the current analyses. Diabetes status was ascertained through biennial in person follow-up. Cox models, with age as the time scale, were used.There were 2369 cases of diabetes (1831 women; 538 men) during an average of 7.3 and 3.6 years of follow-up of the women and men, respectively. In females, menarche age was inversely associated with diabetes risk after adjustment for birth cohort, education, and income (HR = 0.95, 0.92-0.98). In both genders, leg length-to-sitting-height ratio was inversely related to diabetes (HR = 0.88, 0.80-0.97 for men; HR = 0.91, 0.86-0.96 for women) after adjustment for birth cohort, education, and income. Further adjustment for adult BMI at study enrollment completely eliminated the associations of age at menarche (HR = 0.99, 0.96-1.02) and the leg length-to-sitting-height ratio (HR = 1.00, 0.91-1.10 for men; HR = 1.01, 0.96-1.07 for women) with diabetes risk.Our study suggests that markers of an early age at peak height velocity, i.e. early menarche age and low leg-length-to-sitting height ratio, may be associated with diabetes risk later in life and this association is likely to be mediated through obesity

The risks and rewards of covariate adjustment in randomized trials: an assessment of 12 outcomes from 8 studies

Adjustment for prognostic covariates can lead to increased power in the analysis of randomized trials. However, adjusted analyses are not often performed in practice