Enhanced susceptibility of Candida albicans to chlorhexidine under anoxia

Aim: Periodontal pockets can be colonized not only by bacteria, but also by Candida albicans. However, its role in periodontitis is unknown. This study evaluated the inhibitory performance of chlorhexidine digluconate under normoxic and anoxic conditions against 16 strains of C. albicans from periodontal pockets and other 20 from the oral mucosa. Methods: Strains were grown in normoxia and anoxia to adapt themselves to the different atmospheric conditions. Microdilution-based assays were carried out to determine the minimum concentrations of chlorhexidine that may restrain the conditioned candidal strains, in normoxia (normoxic MIC) and anoxia (anoxic MIC). The Mann-Whitney U test was used to evaluate the antimicrobial effect of chlorhexidine on C. albicans under normoxic and anoxic conditions (α = 0.05). Results: The normoxic MIC of chlorhexidine varied broadly from 150 to 1200 μg/mL, whereas its anoxic MIC varied narrower from 2.34 to 37.5 μg/mL. Regarding the origins of strains, no statistically significant differences (p > 0.05) were found. Conclusions: These results indicate that anoxic environmental conditions, compatible with periodontal pockets, tend to enhance C. albicans susceptibility to chlorhexidine.published_or_final_versio

Efficient hydrogen production from the lignocellulosic energy crop Miscanthus by the extreme thermophilic bacteria Caldicellulosiruptor saccharolyticus and Thermotoga neapolitana

<p>Abstract</p> <p>Background</p> <p>The production of hydrogen from biomass by fermentation is one of the routes that can contribute to a future sustainable hydrogen economy. Lignocellulosic biomass is an attractive feedstock because of its abundance, low production costs and high polysaccharide content.</p> <p>Results</p> <p>Batch cultures of <it>Caldicellulosiruptor saccharolyticus </it>and <it>Thermotoga neapolitana </it>produced hydrogen, carbon dioxide and acetic acid as the main products from soluble saccharides in <it>Miscanthus </it>hydrolysate. The presence of fermentation inhibitors, such as furfural and 5-hydroxylmethyl furfural, in this lignocellulosic hydrolysate was avoided by the mild alkaline-pretreatment conditions at a low temperature of 75°C. Both microorganisms simultaneously and completely utilized all pentoses, hexoses and oligomeric saccharides up to a total concentration of 17 g l^-1in pH-controlled batch cultures. <it>T. neapolitana </it>showed a preference for glucose over xylose, which are the main sugars in the hydrolysate. Hydrogen yields of 2.9 to 3.4 mol H₂per mol of hexose, corresponding to 74 to 85% of the theoretical yield, were obtained in these batch fermentations. The yields were higher with cultures of <it>C</it>. <it>saccharolyticus </it>compared to <it>T. neapolitana</it>. In contrast, the rate of substrate consumption and hydrogen production was higher with <it>T. neapolitana</it>. At substrate concentrations exceeding 30 g l^-1, sugar consumption was incomplete, and lower hydrogen yields of 2.0 to 2.4 mol per mol of consumed hexose were obtained.</p> <p>Conclusion</p> <p>Efficient hydrogen production in combination with simultaneous and complete utilization of all saccharides has been obtained during the growth of thermophilic bacteria on hydrolysate of the lignocellulosic feedstock <it>Miscanthus</it>. The use of thermophilic bacteria will therefore significantly contribute to the energy efficiency of a bioprocess for hydrogen production from biomass.</p

A systematic review of evidence for fitness-to-drive among people with the mental health conditions of schizophrenia, stress/anxiety disorder, depression, personality disorder and obsessive compulsive disorder.

Background: Limited evidence exists regarding fitness-to-drive for people with the mental health conditions of schizophrenia, stress/anxiety disorder, depression, personality disorder and obsessive compulsive disorder (herein simply referred to as 'mental health conditions'). The aim of this paper was to systematically search and classify all published studies regarding driving for this population, and then critically appraise papers addressing assessment of fitness-to-drive where the focus was not on the impact of medication on driving. Methods: A systematic search of three databases (CINAHL, PSYCHINFO, EMBASE) was completed from inception to May 2016 to identify all articles on driving and mental health conditions. Papers meeting the eligibility criteria of including data relating to assessment of fitness-to-drive were critically appraised using the American Academy of Neurology and Centre for Evidence-Based Medicine protocols. Results: A total of 58 articles met the inclusion criteria of driving among people with mental health conditions studied, and of these, 16 contained data and an explicit focus on assessment of fitness-to-drive. Assessment of fitness-to-drive was reported in three ways: 1) factors impacting on the ability to drive safely among people with mental health conditions, 2) capability and perception of health professionals assessing fitness-to-drive of people with mental health conditions, and 3) crash rates. The level of evidence of the published studies was low due to the absence of controls, and the inability to pool data from different diagnostic groups. Evidence supporting fitness-todrive is conflicting. Conclusions: There is a relatively small literature in the area of driving with mental health conditions, and the overall quality of studies examining fitness-to-drive is low. Large-scale longitudinal studies with age-matched controls are urgently needed in order to determine the effects of different conditions on fitness-to-drive

Use of the SAW sensor electronic nose for detecting the adulteration of virgin coconut oil with RBD palm kernel olein.

An electronic nose (zNose™) was applied to the detection of adulteration of virgin coconut oil. The system, which is based on a surface acoustic wave sensor was used to generate a pattern of volatile compounds present in the samples. Virgin coconut oil was mixed with refined, bleached and deodorized palm kernel olein at a level of adulteration from 1 to 20% (wt/wt). Adulterant peaks were identified from the chromatogram profile and fitted to a curve using linear regression. The best relationship (R 2 = 0.91) was obtained between the peak tentatively identified as methyl dodecanoate and the percentage of palm kernel olein added. Pearson’s correlation coefficients (r) of 0.92 and 0.89 were obtained between adulterant peak methyl dodecanoate and of the iodine and peroxide values, respectively. Principal component analysis (PCA) was used to differentiate between pure and adulterated samples. The PCA provided good differentiation of samples with 74% of the variation accounted for by PC 1 and 17% accounted for by PC 2. Pure samples formed a separate cluster from all of the adulterated samples

Identification of a novel heterozygous guanosine monophosphate reductase (GMPR) variant in a patient with a late-onset disorder of mitochondrial DNA maintenance

Autosomal dominant progressive external ophthalmoplegia (adPEO) is a late-onset, Mendelian mitochondrial disorder characterised by paresis of the extraocular muscles, ptosis and skeletal-muscle restricted multiple mitochondrial DNA (mtDNA) deletions. While dominantly-inherited, pathogenic variants in POLG, TWNK and RRM2B are among the most common genetic defects of adPEO, identification of novel candidate genes and the underlying pathomechanisms remain challenging. We report the clinical, genetic and molecular investigations of a patient who presented in the seventh decade of life with PEO. Oxidative histochemistry revealed cytochrome c oxidase deficient fibres and occasional ragged red fibres showing subsarcolemmal mitochondrial accumulation in skeletal muscle, while molecular studies identified the presence of multiple mtDNA deletions. Negative candidate screening of known nuclear genes associated with PEO prompted diagnostic exome sequencing, leading to the prioritisation of a novel heterozygous c.547G > C variant in GMPR (NM_006877.3) encoding guanosine monophosphate reductase, a cytosolic enzyme required for maintaining the cellular balance of adenine and guanine nucleotides. We show that the novel c.547G > C variant causes aberrant splicing, decreased GMPR protein levels in patient skeletal muscle, proliferating and quiescent cells and is associated with subtle changes in nucleotide homeostasis protein levels and evidence of disturbed mtDNA maintenance in skeletal muscle. Despite confirmation of GMPR deficiency, demonstrating marked defects of mtDNA replication or nucleotide homeostasis in patient cells proved challenging. Our study proposes that GMPR is the nineteenth (19th) locus for PEO and highlights the complexities of uncovering disease mechanisms in late-onset PEO phenotypes

A single residue substitution in the receptor-binding domain of H5N1 hemagglutinin is critical for packaging into pseudotyped lentiviral particles

© 2012 Tang et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Background: Serological studies for influenza infection and vaccine response often involve microneutralization and hemagglutination inhibition assays to evaluate neutralizing antibodies against human and avian influenza viruses, including H5N1. We have previously characterized lentiviral particles pseudotyped with H5-HA (H5pp) and validated an H5pp-based assay as a safe alternative for high-throughput serological studies in BSL-2 facilities. Here we show that H5-HAs from different clades do not always give rise to efficient production of H5pp and the underlying mechanisms are addressed. Methodology/Findings: We have carried out mutational analysis to delineate the molecular determinants responsible for efficient packaging of HA from A/Cambodia/40808/2005 (H5Cam) and A/Anhui/1/2005 (H5Anh) into H5pp. Our results demonstrate that a single A134V mutation in the 130-loop of the receptor binding domain is sufficient to render H5Anh the ability to generate H5Anh-pp efficiently, whereas the reverse V134A mutation greatly hampers production of H5Cam-pp. Although protein expression in total cell lysates is similar for H5Anh and H5Cam, cell surface expression of H5Cam is detected at a significantly higher level than that of H5Anh. We further demonstrate by several independent lines of evidence that the behaviour of H5Anh can be explained by a stronger binding to sialic acid receptors implicating residue 134. Conclusions: We have identified a single A134V mutation as the molecular determinant in H5-HA for efficient incorporation into H5pp envelope and delineated the underlying mechanism. The reduced binding to sialic acid receptors as a result of the A134V mutation not only exerts a critical influence in pseudotyping efficiency of H5-HA, but has also an impact at the whole virus level. Because A134V substitution has been reported as a naturally occurring mutation in human host, our results may have implications for the understanding of human host adaptation of avian influenza H5N1 virusesThis work was supported by grants from the Research Fund for the Control of Infectious Diseases of Hong Kong (RFCID#08070972), the Area of Excellence Scheme of the University Grants Committee (grant AoE/M-12/-06 of the Hong Kong Special Administrative Region, China), the French Ministry of Health, and the RESPARI project of the Institut Pasteur International Network

Patient Perspectives with Abbreviated versus Standard Pre-Test HIV Counseling in the Prenatal Setting: A Randomized-Controlled, Non-Inferiority Trial

In the US, an unacceptably high percentage of pregnant women do not undergo prenatal HIV testing. Previous studies have found increased uptake of prenatal HIV testing with abbreviated pre-test counseling, however little is known about patient decision making, testing satisfaction and knowledge in this setting.A randomized-controlled, non-inferiority trial was conducted from October 2006 through February 2008 at San Francisco General Hospital (SFGH), the public teaching hospital of the City and County of San Francisco. A total of 278 English- and Spanish-speaking pregnant women were randomized to receive either abbreviated or standard nurse-performed HIV test counseling at the initial prenatal visit. Patient decision making experience was compared between abbreviated versus standard HIV counseling strategies among a sample of low-income, urban, ethnically diverse prenatal patients. The primary outcome was the decisional conflict score (DCS) using O'Connor low-literacy scale and secondary outcomes included satisfaction with test decision, basic HIV knowledge and HIV testing uptake. We conducted an intention-to-treat analysis of 278 women--134 (48.2%) in the abbreviated arm (AA) and 144 (51.8%) in the standard arm (SA). There was no significant difference in the proportion of women with low decisional conflict (71.6% in AA vs. 76.4% in SA, p = .37), and the observed mean difference between the groups of 3.88 (95% CI: -0.65, 8.41) did not exceed the non-inferiority margin. HIV testing uptake was very high (97. 8%) and did not differ significantly between the 2 groups (99.3% in AA vs. 96.5% in SA, p = .12). Likewise, there was no difference in satisfaction with testing decision (97.8% in AA vs. 99.3% in SA, p = .36). However, women in AA had significantly lower mean HIV knowledge scores (78.4%) compared to women in SA (83.7%, p<0.01).This study suggests that streamlining the pre-test counseling process, while associated with slightly lower knowledge, does not compromise patient decision making or satisfaction regarding HIV testing.ClinicalTrials.gov NCT00503308

Worker well-being and the importance of work: bridging the gap

The importance of worker well-being is widely-embraced both in theory and policy, but there are numerous perspectives on what it is, how to measure it, whether it needs improving and if so, how to improve it. We argue that a more complete approach to worker well-being needs to consider workers as full citizens who derive and experience both public and private benefits and costs from working. A broad framework on the meanings of work is used to expand the boundaries of worker well-being to reflect the broad importance of work in human life