2,051 research outputs found
Highly feminised sex ratio estimations for the worldâs third largest nesting aggregation of the loggerhead sea turtle
This is the author accepted manuscript. The final version is available from Inter Research via the DOI in this record.Despite being a fundamental life history character, there is a paucity of population-wide, data-driven studies of primary sex ratios for any marine turtle species. The Republic of Cape Verde hosts the third largest nesting population of loggerhead turtles in the world (hosting up to 15% of global nesting by the species). Weighting for the spatial distribution of nests, we estimate that 84% female hatchlings are currently likely produced across the population, with 85% of nests laid on Boa Vista, where incubation temperatures were coolest. In future climate change scenarios (by 2100), irrespective of beach, island or sand colour, sex ratios reach over 99% female, and three islands (Fogo, Sao Nicolau, Santiago) would cease to produce males, with >90% of nests incubating at lethally high temperatures. Given that most of the population cannot move to nest on cooler islands, we highlight that temporal refugia are amongst primary means available to this population to adapt. Under Low Emissions Scenario, without phenological adaptation, there would only be an estimated 0.14% males produced across the whole population but in Mid and High Emissions Scenarios, male production may cease on most islands
Impact of an Infection Control Program on the Prevalence of Nosocomial Infections at a Tertiary Care Center in Switzerland
Objective. To study the impact of a multimodal infection control program on the rate of nosocomial infections at a 550-bed tertiary care center. Methods. Before and after the implementation of an infection control program, the rate of nosocomial infection was recorded in time-interval prevalence studies. Hand hygiene compliance was studied before and after the intervention. As a surrogate marker of compliance, the amount of alcohol-based hand rub consumed before the intervention was compared with the amount consumed after the intervention. The intervention included additional staff for infection control, repeated instructions for hand hygiene, new guidelines for preoperative antibiotic prophylaxis, and isolation of patients infected or colonized with multidrug-resistant bacteria. Results. The rate of nosocomial infection decreased from approximately 11.7% to 6.8% in 2 years. The rate of hand hygiene compliance increased by 20.0%; it was 59.0% before the intervention and increased to 79.0% afterward. These results correlate with data on the consumption of alcohol-based hand rub, but not with data on the use of antibiotics. Conclusion. Within 2 years, a multimodal infection control program intervention such as this one may reduce the rate of nosocomial infection at a tertiary care center by more than one-third and improve both the quality of care and patient outcomes. It may also generate considerable savings. Therefore, such programs should be promoted not only by hospital epidemiologists but also by hospital administrator
Oligonucleotide Functionalised Microbeads: Indispensable Tools for High-Throughput Aptamer Selection
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Ancient founder mutation is responsible for Imerslund-GrÀsbeck Syndrome among diverse ethnicities
Selection and Characterization of a DNA Aptamer Specifically Targeting Human HECT Ubiquitin Ligase WWP1
published_or_final_versio
Climate effects and stature since 1800
During the last 30 years, economic and social historians have collected and analysed large amounts of anthropometric data in order to explore key aspects of the human past. Attention has also been devoted to the examination of factors that can exert an influence on stature. This article outlines the different ways in which climate might influence stature, either directly or indirectly. It then uses Geographical Information System (GIS) software to explore the relationship between variations in temperature and precipitation and the average heights of men in France, India, Mexico, Spain and the United States (US) over the last two centuries. It is possible to observe an influence of climate on stature in some countries, especially during the nineteenth century, but the relationship weakens across time and largely disappears in recent decades. The attenuation of this relationship is attributed to a process of âtechnophysio evolutionâ as countries modernised and developed economically
Hedgehog/Gli supports androgen signaling in androgen deprived and androgen independent prostate cancer cells
<p>Abstract</p> <p>Background</p> <p>Castration resistant prostate cancer (CRPC) develops as a consequence of hormone therapies used to deplete androgens in advanced prostate cancer patients. CRPC cells are able to grow in a low androgen environment and this is associated with anomalous activity of their endogenous androgen receptor (AR) despite the low systemic androgen levels in the patients. Therefore, the reactivated tumor cell androgen signaling pathway is thought to provide a target for control of CRPC. Previously, we reported that Hedgehog (Hh) signaling was conditionally activated by androgen deprivation in androgen sensitive prostate cancer cells and here we studied the potential for cross-talk between Hh and androgen signaling activities in androgen deprived and androgen independent (AI) prostate cancer cells.</p> <p>Results</p> <p>Treatment of a variety of androgen-deprived or AI prostate cancer cells with the Hh inhibitor, cyclopamine, resulted in dose-dependent modulation of the expression of genes that are regulated by androgen. The effect of cyclopamine on endogenous androgen-regulated gene expression in androgen deprived and AI prostate cancer cells was consistent with the suppressive effects of cyclopamine on the expression of a reporter gene (luciferase) from two different androgen-dependent promoters. Similarly, reduction of smoothened (Smo) expression with siRNA co-suppressed expression of androgen-inducible KLK2 and KLK3 in androgen deprived cells without affecting the expression of androgen receptor (AR) mRNA or protein. Cyclopamine also prevented the outgrowth of AI cells from androgen growth-dependent parental LNCaP cells and suppressed the growth of an overt AI-LNCaP variant whereas supplemental androgen (R1881) restored growth to the AI cells in the presence of cyclopamine. Conversely, overexpression of Gli1 or Gli2 in LNCaP cells enhanced AR-specific gene expression in the absence of androgen. Overexpressed Gli1/Gli2 also enabled parental LNCaP cells to grow in androgen depleted medium. AR protein co-immunoprecipitates with Gli2 protein from transfected 293T cell lysates.</p> <p>Conclusions</p> <p>Collectively, our results indicate that Hh/Gli signaling supports androgen signaling and AI growth in prostate cancer cells in a low androgen environment. The finding that Gli2 co-immunoprecipitates with AR protein suggests that an interaction between these proteins might be the basis for Hedgehog/Gli support of androgen signaling under this condition.</p
The Stature of Boys Is Inversely Correlated to the Levels of Their Sertoli Cell Hormones: Do the Testes Restrain the Maturation of Boys?
The testes of preadolescent boys appear to be dormant, as they produce only trace levels of testosterone [1]. However, they release supra-adult levels of MĂŒllerian Inhibiting Substance (MIS, anti-MĂŒllerian hormone) and lesser levels of inhibin B (InhB), for unknown reasons [2], [3]. Boys have a variable rate of maturation, which on average is slower than girls. The height of children relative to their parents is an index of their maturity [4], [5]. We report here that a boy's level of MIS and InhB is stable over time and negatively correlates with his height and his height relative to his parent's height. This suggests that boy's with high levels of MIS and InhB are short because they are immature, rather than because they are destined to be short men. The levels of MIS and InhB in the boys did not correlate with known hormonal modulators of growth, and were additive with age and the growth hormone/IGF1 axis as predictors of a boy's height. If MIS and InhB were causal regulators of maturity, then the inter-boy differences in the levels of these hormone produces variation in maturation equivalent to 18-months of development. MIS and InhB may thus account for most of the variation in the rate of male development. If boys lacked these hormones, then an average 5-year-old boy would be over 5 cm taller than age-matched girls, making boys almost as dimorphic as men, for height. This indicates that boys have a high growth potential that is initially suppressed by their testes. The concept of the childhood testes suppressing an adult male feature appears paradoxical. However, the growth of children requires intergenerational transfer of nutrients. Consequently, the MIS/InhB slowing of male growth may have been historically advantageous, as it would minimizes any sex bias in the maternal cost of early child rearing
Light is more important than nutrient ratios of fertilization for cymodocea nodosa seedling development
Restoration of seagrass beds through seedlings is an alternative to the transplantation of adult plants that reduces the impact over donor areas and increases the genetic variability of restored meadows. To improve the use of Cymodocea nodosa seedlings, obtained from seeds germinated in vitro, in restoration programs, we investigated the ammonium and phosphate uptake rates of seedlings, and the synergistic effects of light levels (20 and 200 mu mol quanta m(-2) s(-1)) and different nitrogen to phosphorus molar ratios (40 mu M N:10 mu M P, 25 mu M N:25 mu M P, and 10 mu N:40 mu M P) on the photosynthetic activity and growth of seedlings. The nutrient content of seedlings was also compared to the seed nutrient reserves to assess the relative importance of external nutrient uptake for seedling development. Eighty two percent of the seeds germinated after 48 days at a mean rate of 1.5 seeds per day. All seedlings under all treatments survived and grew during the 4 weeks of the experiment. Seedlings of C. nodosa acquired ammonium and phosphate from the incubation media while still attached to the seed, at rates of about twice of adult plants. The relevance of external nutrient uptake was further highlighted by the observation that seedlings' tissues were richer in nitrogen and phosphorus than non-germinated seeds. The uptake of ammonium followed saturation kinetics with a half saturation constant of 32 mu M whereas the uptake of phosphate increased linearly with nutrient concentration within the range tested (5 - 100 mu M). Light was more important than the nutrient ratio of fertilization for the successful development of the young seedlings. The seedlings' photosynthetic and growth rates were about 20% higher in the high light treatment, whereas different nitrogen to phosphorus ratios did not significantly affect growth. The photosynthetic responses of the seedlings to changes in the light level and their capacity to use external nutrient sources showed that seedlings of C. nodosa have the ability to rapidly acclimate to the surrounding light and nutrient environment while still attached to the seeds. C. nodosa seedlings experiencing fertilization under low light levels showed slightly enhanced growth if nourished with a balanced formulation, whereas a slight increase in growth was also observed with unbalanced formulations under a higher light level. Our results highlight the importance of high light availability at the seedling restoration sites.Department of the Environment, Heritage and Climate Change of Gibraltar; FCT, the Portuguese Foundation for Science and Technology [SFRH/BPD/91629/2012]; FCT [UID/Multi/04326/2013
Growth characteristics in individuals with osteogenesis imperfecta in North America: results from a multicenter study.
PurposeOsteogenesis imperfecta (OI) predisposes people to recurrent fractures, bone deformities, and short stature. There is a lack of large-scale systematic studies that have investigated growth parameters in OI.MethodsUsing data from the Linked Clinical Research Centers, we compared height, growth velocity, weight, and body mass index (BMI) in 552 individuals with OI. Height, weight, and BMI were plotted on Centers for Disease Control and Prevention normative curves.ResultsIn children, the median z-scores for height in OI types I, III, and IV were -0.66, -6.91, and -2.79, respectively. Growth velocity was diminished in OI types III and IV. The median z-score for weight in children with OI type III was -4.55. The median z-scores for BMI in children with OI types I, III, and IV were 0.10, 0.91, and 0.67, respectively. Generalized linear model analyses demonstrated that the height z-score was positively correlated with the severity of the OI subtype (Pâ<â0.001), age, bisphosphonate use, and rodding (Pâ<â0.05).ConclusionFrom the largest cohort of individuals with OI, we provide median values for height, weight, and BMI z-scores that can aid the evaluation of overall growth in the clinic setting. This study is an important first step in the generation of OI-specific growth curves
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