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911.
David Simmons A. Toby Prevost Chris Bunn Daniel Holman Richard A. Parker Simon Cohn Sarah Donald Charlotte A. M. Paddison Candice Ward Peter Robins Jonathan Graffy 《PloS one》2015,10(3)
Background
Diabetes peer support, where one person with diabetes helps guide and support others, has been proposed as a way to improve diabetes management. We have tested whether different diabetes peer support strategies can improve metabolic and/or psychological outcomes.Methods
People with type 2 diabetes (n = 1,299) were invited to participate as either ‘peer’ or ‘peer support facilitator’ (PSF) in a 2x2 factorial randomised cluster controlled trial across rural communities (130 clusters) in England. Peer support was delivered over 8–12 months by trained PSFs, supported by monthly meetings with a diabetes educator. Primary end point was HbA1c. Secondary outcomes included quality of life, diabetes distress, blood pressure, waist, total cholesterol and weight. Outcome assessors and investigators were masked to arm allocation. Main factors were 1:1 or group intervention. Analysis was by intention-to-treat adjusting for baseline.Results
The 4 arms were well matched (Group n = 330, 1:1(individual) n = 325, combined n = 322, control n = 322); 1035 (79•7%) completed the mid-point postal questionnaire and 1064 (81•9%) had a final HbA1c. A limitation was that although 92.6% PSFs and peers were in telephone contact, only 61.4% of intervention participants attended a face to face session. Mean baseline HbA1c was 57 mmol/mol (7•4%), with no significant change across arms. Follow up systolic blood pressure was 2•3mm Hg (0.6 to 4.0) lower among those allocated group peer-support and 3•0mm Hg (1.1 to 5.0) lower if the group support was attended at least once. There was no impact on other outcomes by intention to treat or significant differences between arms in self-reported adherence or medication.Conclusions
Group diabetes peer support over 8–12 months was associated with a small improvement in blood pressure but no other significant outcomes. Long term benefits should be investigated.Trial Registration
ISRCTN.com ISRCTN6696362166963621 相似文献912.
Brady W. Bennett Brandon D. L. Marshall Annie Gjelsvik Stephen T. McGarvey Mark N. Lurie 《PloS one》2015,10(11)
Objectives
The aim of this study was to determine the association between violent conflict and HIV incidence within and across 36 sub-Saharan Africa countries between 1990 and 2012.Methods
We used generalized linear mixed effect modeling to estimate the effect of conflict periods on country-level HIV incidence. We specified random intercepts and slopes to account for across and within country variation over time. We also conducted a sub-analysis of countries who experienced conflict to assess the effect of conflict intensity on country-level HIV incidence. All models controlled for level of economic development, number of refugees present in the country, and year.Results
We found that, compared to times of peace, the HIV incidence rate increased by 2.1 per 1000 infections per year (95%CI: 0.39, 3.87) in the 5 years prior to conflict. Additionally, we found a decrease of 0.7 new infections per 1000 people per year (95%CI: -1.44, -0.01) in conflicts with 25 to 1000 battle-related deaths and a decrease of 1.5 new infections per 1000 people per year (95%CI:-2.50, -0.52) for conflict with more than 1000 battle-related deaths, compared to conflicts with less than 25 battle-related deathsConclusions
Our results demonstrate that HIV infection rates increase in the years immediately prior to times of conflict; however, we did not identify a significant increase during and immediately following periods of violent conflict. Further investigation, including more rigorous data collection, is needed, as is increased aid to nations at risk of violent conflict to help in the fight against HIV/AIDS in sub-Saharan Africa. 相似文献913.
Cyprian E. Oshoma Darren Greetham Edward J. Louis Katherine A. Smart Trevor G. Phister Chris Powell Chenyu Du 《PloS one》2015,10(8)
Formic acid is one of the major inhibitory compounds present in hydrolysates derived from lignocellulosic materials, the presence of which can significantly hamper the efficiency of converting available sugars into bioethanol. This study investigated the potential for screening formic acid tolerance in non-Saccharomyces cerevisiae yeast strains, which could be used for the development of advanced generation bioethanol processes. Spot plate and phenotypic microarray methods were used to screen the formic acid tolerance of 7 non-Saccharomyces cerevisiae yeasts. S. kudriavzeii IFO1802 and S. arboricolus 2.3319 displayed a higher formic acid tolerance when compared to other strains in the study. Strain S. arboricolus 2.3319 was selected for further investigation due to its genetic variability among the Saccharomyces species as related to Saccharomyces cerevisiae and availability of two sibling strains: S. arboricolus 2.3317 and 2.3318 in the lab. The tolerance of S. arboricolus strains (2.3317, 2.3318 and 2.3319) to formic acid was further investigated by lab-scale fermentation analysis, and compared with S. cerevisiae NCYC2592. S. arboricolus 2.3319 demonstrated improved formic acid tolerance and a similar bioethanol synthesis capacity to S. cerevisiae NCYC2592, while S. arboricolus 2.3317 and 2.3318 exhibited an overall inferior performance. Metabolite analysis indicated that S. arboricolus strain 2.3319 accumulated comparatively high concentrations of glycerol and glycogen, which may have contributed to its ability to tolerate high levels of formic acid. 相似文献
914.
Background
Polycyclic aromatic hydrocarbons (PAH) are both man-made and naturally occurring environmental pollutants that may be related to cardiometabolic health risk.Objective
To determine whether PAH is associated with obesity in the adult population and to examine whether urinary concentrations of PAH metabolites are associated with differences in how obesity relates to 3 or more risk factors for the metabolic syndrome (3RFMetS), type 2 diabetes (T2D), hypertension, and dyslipidemia.Methods
A total of 4765 adult participants from the 2001–2008 National Health and Nutrition Examination Survey were examined. The association between 8 urinary hydroxylated PAH metabolites, obesity, and health were examined using weighted logistic regressions adjusting for age, sex, ethnicity, PIR, smoking status, and urinary creatinine.Results
There was a positive dose-dependent association between obesity and 2-phenanthrene quintiles (P trend <0.0001). Contrarily, higher quintiles of 1-naphthalene were associated with lower risk of obesity (P trend = 0.0004). For a given BMI, those in the highest quintile of 2-naphthalene, 2-fluorene, 3-fluorene and 2-phenanthrene had a 66–80% greater likelihood of 3RFMetS (P≤0.05) compared to low levels. Higher quintiles of 1-naphthalene, 2-naphthalene, 2-phenanthrene and 1-pyrene were associated with a 78–124% greater likelihood of T2D (P≤0.05) compared to low levels while high 1-naphthalene, 2-naphthalene, 2-fluorene, 3-fluorene and 2-phenanthrene were associated with a 38–68% greater likelihood of dyslipidemia (P≤0.05) compared to lower levels. Finally, 2-naphthalene and 2-phenanthrene were positively associated with hypertension (P trend = 0.008 and P trend = 0.02 respectively).Conclusions
PAH is related to obesity and the expression of a number of obesity-related cardiometabolic health risk factors. Future research is needed to bring to light the mechanistic pathways related to these findings. 相似文献915.
Michael J. Lawes Diana O. Fisher Chris N. Johnson Simon P. Blomberg Anke S. K. Frank Susanne A. Fritz Hamish McCallum Jeremy VanDerWal Brett N. Abbott Sarah Legge Mike Letnic Colette R. Thomas Nikki Thurgate Alaric Fisher Iain J. Gordon Alex Kutt 《PloS one》2015,10(6)
Australia has experienced dramatic declines and extinctions of its native rodent species over the last 200 years, particularly in southern Australia. In the tropical savanna of northern Australia significant declines have occurred only in recent decades. The later onset of these declines suggests that the causes may differ from earlier declines in the south. We examine potential regional effects (northern versus southern Australia) on biological and ecological correlates of range decline in Australian rodents. We demonstrate that rodent declines have been greater in the south than in the tropical north, are strongly influenced by phylogeny, and are consistently greater for species inhabiting relatively open or sparsely vegetated habitat. Unlike in marsupials, where some species have much larger body size than rodents, body mass was not an important predictor of decline in rodents. All Australian rodent species are within the prey-size range of cats (throughout the continent) and red foxes (in the south). Contrary to the hypothesis that mammal declines are related directly to ecosystem productivity (annual rainfall), our results are consistent with the hypothesis that disturbances such as fire and grazing, which occur in non-rainforest habitats and remove cover used by rodents for shelter, nesting and foraging, increase predation risk. We agree with calls to introduce conservation management that limits the size and intensity of fires, increases fire patchiness and reduces grazing impacts at ecological scales appropriate for rodents. Controlling feral predators, even creating predator-free reserves in relatively sparsely-vegetated habitats, is urgently required to ensure the survival of rodent species, particularly in northern Australia where declines are not yet as severe as those in the south. 相似文献
916.
917.
Patrick D. Brandt Susi Sturzenegger Varvayanis Tracey Baas Amanda F. Bolgioni Janet Alder Kimberly A. Petrie Isabel Dominguez Abigail M. Brown C. Abigail Stayart Harinder Singh Audra Van Wart Christine S. Chow Ambika Mathur Barbara M. Schreiber David A. Fruman Brent Bowden Christopher A. Wiesen Yvonne M. Golightly Chris E. Holmquist Daniel Arneman Joshua D. Hall Linda E. Hyman Kathleen L. Gould Roger Chalkley Patrick J. Brennwald Rebekah L. Layton 《PLoS biology》2021,19(7)
918.
Most Old World mice and rats, subfamily Murinae, have a spermatozoon with an apical hook, a long tail and, as seen typically in eutherian mammals, a bilaterally flattened head. Dramatically different from this are the sperm of the Greater Bandicoot Rat, Bandicota indica. Here, we ask the question has the structure of the sperm head co‐evolved with that of the egg coat, the zona pellucida? For this, we first summarise the morphological features of the spermatozoon of B. indica that may relate to zona pellucida penetration at the time of fertilisation, and we confirm that the sperm head is generally round, not bilaterally flattened, in profile and has a huge acrosome. We then show that the zona pellucida around oocytes in tertiary follicles also differs from that of the other murine rodents in being only about 4 μm thick and, as demonstrated by lectin staining, has an unusual abundance of alpha‐L‐fucose. These findings indicate that both the male and female gametes of this South‐East Asian murine rodent are highly divergent in their structural organisation. One of the functional implications of this probably relates to sperm–zona interactions and the release of acrosomal enzymes that probably facilitate penetration by digestion of the zona matrix at the time of fertilisation. 相似文献
919.
Chandree?L. Beaulieu Jacek Majewski Jeremy Schwartzentruber Mark?E. Samuels Bridget?A. Fernandez Francois?P. Bernier Michael Brudno Bartha Knoppers Janet Marcadier David Dyment Shelin Adam Dennis?E. Bulman Steve?J.M. Jones Denise Avard Minh?Thu Nguyen Francois Rousseau Christian Marshall Richard?F. Wintle Yaoqing Shen Stephen?W. Scherer FORGE Canada Consortium Jan?M. Friedman Jacques?L. Michaud Kym?M. Boycott 《American journal of human genetics》2014,94(6):809-817
Inherited monogenic disease has an enormous impact on the well-being of children and their families. Over half of the children living with one of these conditions are without a molecular diagnosis because of the rarity of the disease, the marked clinical heterogeneity, and the reality that there are thousands of rare diseases for which causative mutations have yet to be identified. It is in this context that in 2010 a Canadian consortium was formed to rapidly identify mutations causing a wide spectrum of pediatric-onset rare diseases by using whole-exome sequencing. The FORGE (Finding of Rare Disease Genes) Canada Consortium brought together clinicians and scientists from 21 genetics centers and three science and technology innovation centers from across Canada. From nation-wide requests for proposals, 264 disorders were selected for study from the 371 submitted; disease-causing variants (including in 67 genes not previously associated with human disease; 41 of these have been genetically or functionally validated, and 26 are currently under study) were identified for 146 disorders over a 2-year period. Here, we present our experience with four strategies employed for gene discovery and discuss FORGE’s impact in a number of realms, from clinical diagnostics to the broadening of the phenotypic spectrum of many diseases to the biological insight gained into both disease states and normal human development. Lastly, on the basis of this experience, we discuss the way forward for rare-disease genetic discovery both in Canada and internationally. 相似文献
920.
Udayananth Aich Deanna C. Hurum Lipika Basumallick Srinivasa Rao Chris Pohl Jeffrey S. Rohrer Sebastian Kandzia 《Analytical biochemistry》2014
Labeling of released asparagine-linked (N-linked) oligosaccharides from glycoproteins is commonly performed to aid in the separation and detection of the oligosaccharide. Of the many available oligosaccharide labels, 2-amino benzamide (2-AB) is a popular choice for providing a fluorescent product. The derivatization conditions can potentially lead to oligosaccharide desialylation. This work evaluated the extent of sialic acid loss during 2-AB labeling of N-linked oligosaccharides released from bovine fetuin, polyclonal human serum immunoglobulin G (IgG), and human α1-acid glycoprotein (AGP) as well as of sialylated oligosaccharide reference standards and found that for more highly sialylated oligosaccharides the loss is greater than the <2% value commonly cited. Manufacturers of glycoprotein biotherapeutics need to produce products with a consistent state of sialylation and, therefore, require an accurate assessment of glycoprotein sialylation. 相似文献