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21.

Objective

We aimed to study current practices in growth monitoring by European primary care paediatricians and to explore their perceived needs in this field.

Methods

We developed a cross-sectional, anonymous on-line survey and contacted primary care paediatricians listed in national directories in the 18 European countries with a confederation of primary care paediatricians. Paediatricians participated in the survey between April and September 2011.

Results

Of the 1,198 paediatricians from 11 European countries (response rate 13%) who participated, 29% used the 2006 World Health Organization Multicentre Growth Reference Study growth charts, 69% used national growth charts; 61% used software to draw growth charts and 79% did not use a formal algorithm to detect abnormal growth on growth charts. Among the 21% of paediatricians who used algorithms, many used non-algorithmic simple thresholds for height and weight and none used the algorithms published in the international literature. In all, 69% of paediatricians declared that a validated algorithm to monitor growth would be useful in daily practice. We found important between-country variations.

Conclusion

The varied growth-monitoring practices declared by primary care paediatricians reveals the need for standardization and evidence-based algorithms to define abnormal growth and the development of software that would use such algorithms.  相似文献   
22.
23.
The One Health initiative is a global effort fostering interdisciplinary collaborations to address challenges in human, animal, and environmental health. While One Health has received considerable press, its benefits remain unclear because its effects have not been quantitatively described. We systematically surveyed the published literature and used social network analysis to measure interdisciplinarity in One Health studies constructing dynamic pathogen transmission models. The number of publications fulfilling our search criteria increased by 14.6% per year, which is faster than growth rates for life sciences as a whole and for most biology subdisciplines. Surveyed publications clustered into three communities: one used by ecologists, one used by veterinarians, and a third diverse-authorship community used by population biologists, mathematicians, epidemiologists, and experts in human health. Overlap between these communities increased through time in terms of author number, diversity of co-author affiliations, and diversity of citations. However, communities continue to differ in the systems studied, questions asked, and methods employed. While the infectious disease research community has made significant progress toward integrating its participating disciplines, some segregation—especially along the veterinary/ecological research interface—remains.  相似文献   
24.
ABSTRACT: BACKGROUND: Severe malaria is a medical emergency with high mortality. Prompt achievement of therapeutic concentrations of highly effective anti-malarial drugs reduces the risk of death. The aim of this study was to assess the pharmacokinetics and pharmacodynamics of intravenous artesunate in Ugandan adults with severe malaria. METHODS: Fourteen adults with severe falciparum malaria requiring parenteral therapy were treated with 2.4 mg/kg intravenous artesunate. Blood samples were collected after the initial dose and plasma concentrations of artesunate and dihydroartemisinin measured by solid-phase extraction and liquid chromatography-tandem mass spectrometry. The study was approved by the Makerere University Faculty of Medicine Research and Ethics Committee (Ref2010-015) and Uganda National Council of Science and Technology (HS605) and registered with ClinicalTrials.gov (NCT01122134). RESULTS: All study participants achieved prompt resolution of symptoms and complete parasite clearance with median (range) parasite clearance time of 17 (8-24) hours. Median (range) maximal artesunate concentration (Cmax) was 3260 (1020-164000) ng/mL, terminal elimination half-life (T1/2) was 0.25 (0.1-1.8) hours and total artesunate exposure (AUC) was 727 (290-111256) ngh/mL. Median (range) dihydroartemisinin Cmax was 3140 (1670-9530) ng/mL, with Tmax of 0.14 (0.6 - 6.07) hours and T1/2 of 1.31 (0.8-2.8) hours. Dihydroartemisinin AUC was 3492 (2183-6338) ngh/mL. None of the participants reported adverse events. CONCLUSIONS: Plasma concentrations of artesunate and dihydroartemisinin were achieved rapidly with rapid and complete symptom resolution and parasite clearance with no adverse events.  相似文献   
25.
The action spectrum for promotion of elongation of protonemata of Onoclea sensibilis has peaks at 400–420, 580–600 and 640–660 nm. The largest growth increments at saturating light doses are produced by yellow and far-red light. Elongation induced by yellow and far-red irradiation persists in old as well as young filaments, while red-light promotion is found only in young filaments. The growth promotion caused by yellow light is partially reversed by red light down to the level of growth produced by red irradiation alone. Elongation of rhizoids is under reversible red, far-red control, while yellow light is inactive. A model is proposed and discussed in which the light-sensitive elongation of filaments is accounted for by the presence of three distinct photoreceptors: phytochrome; a pigment absorbing yellow light. P580; and a pigment absorbing blue light, P420.  相似文献   
26.

Rhodobacter sphaeroides is a metabolically versatile bacterium capable of producing terpenes natively. Surprisingly, terpene biosynthesis in this species has always been investigated in complex media, with unknown compounds possibly acting as carbon and nitrogen sources. Here, a defined medium was adapted for R. sphaeroides dark heterotrophic growth, and was used to investigate the conversion of different organic substrates into the reporter terpene amorphadiene. The amorphadiene synthase was cloned in R. sphaeroides, allowing its biosynthesis via the native 2-methyl-d-erythritol-4-phosphate (MEP) pathway and, additionally, via a heterologous mevalonate one. The latter condition increased titers up to eightfold. Consequently, better yields and productivities to previously reported complex media cultivations were achieved. Productivity was further investigated under different cultivation conditions, including nitrogen and oxygen availability. This novel cultivation setup provided useful insight into the understanding of terpene biosynthesis in R. sphaeroides, allowing to better comprehend its dynamics and regulation during chemoheterotrophic cultivation.

  相似文献   
27.
Psychological stress is one of the factors associated with human cardiovascular disease. Here, we demonstrate that acute perceived stress impairs the natural capacity of heart regeneration in zebrafish. Beside physical and chemical disturbances, intermittent crowding triggered an increase in cortisol secretion and blocked the replacement of fibrotic tissue with new myocardium. Pharmacological simulation of stress by pulse treatment with dexamethasone/adrenaline reproduced the regeneration failure, while inhibition of the stress response with anxiolytic drugs partially rescued the regenerative process. Impaired heart regeneration in stressed animals was associated with a reduced cardiomyocyte proliferation and with the downregulation of several genes, including igfbp1b, a modulator of IGF signalling. Notably, daily stress induced a decrease in Igf1r phosphorylation. As cardiomyocyte proliferation was decreased in response to IGF-1 receptor inhibition, we propose that the stress-induced cardiac regenerative failure is partially caused by the attenuation of IGF signalling. These findings indicate that the natural regenerative ability of the zebrafish heart is vulnerable to the systemic paracrine stress response.  相似文献   
28.
Demography, migration and natural selection are predominant processes affecting the distribution of genetic variation among natural populations. Many studies use neutral genetic markers to make inferences about population history. However, the investigation of functional coding loci, which directly reflect fitness, is critical to our understanding of species'' ecology and evolution. Immune genes, such as those of the Major Histocompatibility Complex (MHC), play an important role in pathogen recognition and provide a potent model system for studying selection. We contrasted diversity patterns of neutral data with MHC loci, ELA-DRA and -DQA, in two southern African plains zebra (Equus quagga) populations: Etosha National Park, Namibia, and Kruger National Park, South Africa. Results from neutrality tests, along with observations of elevated diversity and low differentiation across populations, supported previous genus-level evidence for balancing selection at these loci. Despite being low, MHC divergence across populations was significant and may be attributed to drift effects typical of geographically separated populations experiencing little to no gene flow, or alternatively to shifting allele frequency distributions driven by spatially variable and fluctuating pathogen communities. At the DRA, zebra exhibited geographic differentiation concordant with microsatellites and reduced levels of diversity in Etosha due to highly skewed allele frequencies that could not be explained by demography, suggestive of spatially heterogeneous selection and local adaptation. This study highlights the complexity in which selection affects immune gene diversity and warrants the need for further research on the ecological mechanisms shaping patterns of adaptive variation among natural populations.  相似文献   
29.

Purpose  

A life cycle assessment (LCA) was conducted on winter wheat, based on real agricultural practices databases, on a sample divided into four production scenarios. The main objectives of this study are (1) to assess the environmental impact of winter wheat, using an LCA covering field practices, and the transport and storage of grain until it is sold to a miller; (2) to use the USEtox model (Rosenbaum et al. in Int J Life Cycle Assess 13:532–546, 2008) to assess the part of the total freshwater ecotoxicity impact due to pesticide use, its variability among plots, and to identify the active ingredients with the strongest impact; (3) and with the help of fungicide, insecticide, herbicide experts, to identify active ingredients to replace these high-impact pesticides and estimate the effect of such a substitution on total freshwater ecotoxicity.  相似文献   
30.
Ansquer P  Duru M  Theau JP  Cruz P 《Annals of botany》2009,103(1):117-126
Background and Aims: Fodder provision in species-rich grasslands, i.e. herbage growth,proportion of leaf, and leaf and stem digestibility, is difficultto predict for short periods of time, such as between two defoliationsor less. The value of two methods based on plant traits forevaluating these agronomic properties was examined. Methods: One method is based on plant trait measurements on the plantcommunity (leaf dry matter content, plant height, floweringdate); the other is on vegetation composition expressed as plantfunctional types (acquisitive versus conservative PFTs) establishedby measuring leaf dry matter content on pure grass stands. Theexperiment consisted of 18 fields with three different defoliationregimes (combinations of cutting and grazing) and two levelsof fertilization. To establish a growth curve over the firstgrowth cycle, herbage was sampled about 10 times in spring. Key Results: Coefficients of correlation between agronomic properties ofthe vegetation and its functional composition were higher whenthe latter was assessed through PFT and an indicator of theplant nutrient status (Ni) instead of measured plant traits.The date at which the ceiling yield occurred for the standingherbage mass or only the leaf component, which varied by upto 500 degree-days between treatments, and the leaf proportion,depended entirely on the PFT, and largely so for the leaf digestibility.The standing herbage mass at the time of ceiling yield dependedonly on Ni, or mainly so in the case of the daily herbage growthrate. Similar plant digestibility between plant communitieswas found at flowering time, although there were big differencesin PFT composition. The shape of the growth curve was flatterwhen there was great functional diversity in the plant community. Conclusions: The PFT composition and the Ni were more reliable than the plantfunctional traits measured in the field for evaluating herbagegrowth pattern and digestibility in spring.  相似文献   
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