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901.
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903.
Neurochemical Research - Cocaine is a highly addictive stimulant with diverse effects on physiology. Recent studies indicate the involvement of extracellular vesicles (EVs) secreted by neural cells...  相似文献   
904.
In urban environments, green roofs provide a number of benefits, including decreased urban heat island effects and reduced energy costs for buildings. However, little research has been done on the non-plant biota associated with green roofs, which likely affect their functionality. For the current study, we evaluated whether or not green roofs planted with two native plant communities in New York City functioned as habitats for soil fungal communities, and compared fungal communities in green roof growing media to soil microbial composition in five city parks, including Central Park and the High Line. Ten replicate roofs were sampled one year after planting; three of these roofs were more intensively sampled and compared to nearby city parks. Using Illumina sequencing of the fungal ITS region we found that green roofs supported a diverse fungal community, with numerous taxa belonging to fungal groups capable of surviving in disturbed and polluted habitats. Across roofs, there was significant biogeographical clustering of fungal communities, indicating that community assembly of roof microbes across the greater New York City area is locally variable. Green roof fungal communities were compositionally distinct from city parks and only 54% of the green roof taxa were also found in the park soils. Phospholipid fatty acid analysis revealed that park soils had greater microbial biomass and higher bacterial to fungal ratios than green roof substrates. City park soils were also more enriched with heavy metals, had lower pH, and lower quantities of total bases (Ca, K, and Mg) compared to green roof substrates. While fungal communities were compositionally distinct across green roofs, they did not differentiate by plant community. Together, these results suggest that fungi living in the growing medium of green roofs may be an underestimated component of these biotic systems functioning to support some of the valued ecological services of green roofs.  相似文献   
905.
906.
Enteroviruses (EVs) are a major cause of aseptic meningitis, and RNA detection using molecular assay is the gold standard diagnostic test. The aim of this study was to assess the impact of an EV positive diagnosis on the clinical management of patients admitted for meningitis over the course of two observational study periods (2005 and 2008–09) in the same clinical departments. We further investigated in multivariate analysis various factors possibly associated with hospital length of stay (LOS) in all age groups (infants, children, and adults). The results showed an overall improvement in the management of patients (n = 142) between the study periods, resulting in a significantly shorter hospital LOS for adults and children, and a shorter duration of antibiotic use for adults and infants. In multivariate analysis, we observed that the time from molecular test results to discharge of patients and the median duration of antibiotic treatment were associated with an increase in LOS in all age groups. In addition, among adults, the turnaround time of the molecular assay was significantly correlated with LOS. The use of CT scan in children and hospital admission outside the peak of EV prevalence in infants tended to increase LOS. In conclusion, the shorter length of stay of patients with meningitis in this study was due to various factors including the rapidity of the EV molecular test (particularly in adults), greater physician responsiveness after a positive result (in adults and children), and greater experience on the part of physicians in handling EV meningitis, as evidenced by the shorter duration of antibiotic use in adults and infants.  相似文献   
907.

Background

The majority of the patients reported with mutations in isolated hypogonadotropic hypogonadism (HH) are adults. We analysed the presentation and the plasma inhibin B and anti-müllerian hormone (AMH) concentrations during childhood and adolescence, and compared them to the genetic results.

Methods

This was a retrospective, single-center study of 46 boys with HH.

Results

Fourteen (30.4%) had Kallmann syndrome (KS), 4 (8.7%) had CHARGE syndrome and 28 (60.9%) had HH without olfaction deficit nor olfactive bulb hypoplasia. Eighteen (39%) had an associated malformation or syndromes. At diagnosis, 22 (47.8%) boys were aged <one year, 9 (19%) 1–11 and 15 (32.6%) 11–17.6 years. They presented with micropenis (n = 32, 69.6%, including all those <one year), cryptorchidism (n = 32, 69.6%, unilateral in 8, bilateral in 24), and/or pubertal delay (n = 11). The plasma inhibin B concentrations were normal in 8 (3 KS including one CHARGE and 5 other HH), at the lower limit of the normal in 6 and decreased in 13 (48%) boys. The AMH concentrations were normal in 15 (6 KS including one CHARGE and 9 other HH) and decreased in 12 (44%) boys. In addition to the CHD7 gene mutations in 4 patients with CHARGE, mutations were found in 5/26 other boys analysed including one in KAL1 gene with STS, 2 in FGFR1 gene, one in PROKR2 gene and one in GnRHR gene.

Conclusions

The presence of micropenis in neonate, particularly if associated with cryptorchidism, is an indication to look for gonadotropin deficiency isolated or associated with other hypothalamic-pituitary deficiencies. Inhibin B and AMH concentrations are suggestive if low, but they may be normal. Despite the high frequency of the associated malformations and excluding the patients with CHARGE or ichtyosis, the 4 patients with mutations had no family history or malformation. This suggests that many other genes are involved.  相似文献   
908.

Introduction

Community mobilizing strategies are essential to health promotion and uptake of HIV prevention. However, there has been little conceptual work conducted to establish the core components of community mobilization, which are needed to guide HIV prevention programming and evaluation.

Objectives

We aimed to identify the key domains of community mobilization (CM) essential to change health outcomes or behaviors, and to determine whether these hypothesized CM domains were relevant to a rural South African setting.

Method

We studied social movements and community capacity, empowerment and development literatures, assessing common elements needed to operationalize HIV programs at a community level. After synthesizing these elements into six essential CM domains, we explored the salience of these CM domains qualitatively, through analysis of 10 key informant in-depth-interviews and seven focus groups in three villages in Bushbuckridge.

Results

CM domains include: 1) shared concerns, 2) critical consciousness, 3) organizational structures/networks, 4) leadership (individual and/or institutional), 5) collective activities/actions, and 6) social cohesion. Qualitative data indicated that the proposed domains tapped into theoretically consistent constructs comprising aspects of CM processes. Some domains, extracted from largely Western theory, required little adaptation for the South African context; others translated less effortlessly. For example, critical consciousness to collectively question and resolve community challenges functioned as expected. However, organizations/networks, while essential, operated differently than originally hypothesized - not through formal organizations, but through diffuse family networks.

Conclusions

To date, few community mobilizing efforts in HIV prevention have clearly defined the meaning and domains of CM prior to intervention design. We distilled six CM domains from the literature; all were pertinent to mobilization in rural South Africa. While some adaptation of specific domains is required, they provide an extremely valuable organizational tool to guide CM programming and evaluation of critically needed mobilizing initiatives in Southern Africa.  相似文献   
909.
Vitelliform macular dystrophies (VMD) are inherited retinal dystrophies characterized by yellow, round deposits visible upon fundus examination and encountered in individuals with juvenile Best macular dystrophy (BMD) or adult-onset vitelliform macular dystrophy (AVMD). Although many BMD and some AVMD cases harbor mutations in BEST1 or PRPH2, the underlying genetic cause remains unknown for many affected individuals. In a large family with autosomal-dominant VMD, gene mapping and whole-exome sequencing led to the identification of a c.713T>G (p.Leu238Arg) IMPG1 mutation, which was subsequently found in two other families with autosomal-dominant VMD and the same phenotype. IMPG1 encodes the SPACR protein, a component of the rod and cone photoreceptor extracellular matrix domains. Structural modeling indicates that the p.Leu238Arg substitution destabilizes the conserved SEA1 domain of SPACR. Screening of 144 probands who had various forms of macular dystrophy revealed three other IMPG1 mutations. Two individuals from one family affected by autosomal-recessive VMD were homozygous for the splice-site mutation c.807+1G>T, and two from another family were compound heterozygous for the mutations c.461T>C (p.Leu154Pro) and c.1519C>T (p.Arg507). Most cases had a normal or moderately decreased electrooculogram Arden ratio. We conclude that IMPG1 mutations cause both autosomal-dominant and -recessive forms of VMD, thus indicating that impairment of the interphotoreceptor matrix might be a general cause of VMD.  相似文献   
910.
Although it is no longer debatable that sedentary behaviors are an actual cause of many metabolic diseases, the physiology of physical inactivity has been poorly investigated for this purpose. Along with microgravity, the physiological adaptations to spaceflights require metabolic adaptations to physical inactivity, and that is exceedingly well-simulated during the ground-based microgravity bed-rest analogs. Bed rest thus represents a unique model to investigate the mechanisms by which physical inactivity leads to the development of current societal chronic diseases. For decades, however, clinicians and physiologists working in space research have worked separately without taking full awareness of potential strong mutual questioning. This review summarizes the data collected over the last 60 years on metabolic adaptations to bed rest in healthy subjects. Our aim is to provide evidence that supports the hypothesis that physical inactivity per se is one of the primary causes in the development of metabolic inflexibility. This evidence will focus on four main tenants of metabolic inflexiblity: 1) insulin resistance, 2) impaired lipid trafficking and hyperlipidemia, 3) a shift in substrate use toward glucose, and 4) a shift in muscle fiber type and ectopic fat storage. Altogether, this hypothesis places sedentary behaviors upstream on the list of factors involved in metabolic inflexibility, which is considered to be a primary impairment in several metabolic disorders such as obesity, insulin resistance, and type 2 diabetes mellitus.  相似文献   
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