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Inhaled corticosteroids (ICS) are effective treatment for older children and adults with asthma. Pathological studies have established that eosinophilic inflammation is important especially in mild to moderate asthma, thus providing a rationale for ICS treatment. However, we have wrongly concluded in the past that early and aggressive treatment of asthma is needed to prevent irreversible scarring and airflow obstruction. We have increasing evidence from all age groups that there are non-eosinophilic asthma phenotypes, that remodelling is independent of inflammation, and that steroids do not prevent children developing progressive airflow obstruction. Asthma treatments that are valuable in adults may not be effective in children, and safe prescribing requires paediatric clinical trials. In young preschool children, the evidence for any eosinophilic airway inflammation is scant, the symptomatic benefit of inhaled steroids is meagre, and there is clear evidence that ICS do not modify the natural history. There is also the potential for steroids to interfere with the developing lung. Thus, we believe that ICS should not be prescribed in primary care for children under two years of age, and that if these children are thought to need more than intermittent therapy with beta-agonists or possibly leukotriene antagonists, specialist referral is mandatory.  相似文献   
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Prior work proposed a shortened version of the Social Responsiveness Scale (SRS), a commonly used quantitative measure of social communication traits. We used data from 3031 participants (including 190 ASD cases) from the Environmental Influences on Child Health Outcomes (ECHO) Program to compare distributional properties and criterion validity of 16-item “short” to 65-item “full” SRS scores. Results demonstrated highly overlapping distributions of short and full scores. Both scores separated case from non-case individuals by approximately two standard deviations. ASD prediction was nearly identical for short and full scores (area under the curve values of 0.87, 0.86 respectively). Findings support comparability of shortened and full scores, suggesting opportunities to increase efficiency. Future work should confirm additional psychometric properties of short scores.

  相似文献   
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Broudy  VC; Lin  NL; Fox  N; Taga  T; Saito  M; Kaushansky  K 《Blood》1996,88(6):2026-2032
Thrombopoietin (Tpo), the ligand for the c-Mpl receptor, is a major regulator of megakaryopoiesis. Treatment of mice with Tpo raises the platelet count fourfold within a few days. Conversely, c-mpl knock-out mice have platelet counts that are 15% that of normal. The subunit structure of the c-Mpl receptor is not fully understood. Some cytokines that stimulate megakaryopoiesis (IL-6, IL-11, leukemia inhibitory factor, and oncostatin M) bind to receptors that use gp130 as a signal transduction subunit. For these reasons, we determined whether gp130 function was required for Tpo-induced signal transduction. Murine marrow cells were cultured in semi-solid media in the presence of Tpo or IL-3, with or without a neutralizing anti-gp130 monoclonal antibody (RX187) or a soluble form of c-Mpl receptor (soluble Mpl) that blocks Tpo bioactivity, and the numbers of colony-forming unit-megakaryocyte (CFU-Meg) colonies were counted on day 5. Murine marrow cells were also cultured in suspension under serum-free conditions for 5 days, and megakaryocyte DNA content was measured by flow cytometry, as an index of nuclear maturation. The addition of RX187 did not block Tpo-induced CFU-Meg colony growth nor CFU-Meg nuclear maturation in suspension culture. However, IL-3-induced CFU-Meg colony growth and megakaryocyte nuclear maturation decreased in the presence of RX187. Soluble Mpl completely ablated Tpo-induced CFU-Meg growth, and partially blocked IL- 3-stimulated CFU-Meg growth. Thus the effects of Tpo on megakaryopoiesis in vitro do not depend on cytokines that signal through gp130. Furthermore, it is unlikely that gp 130 serves as a beta chain for the c-Mpl receptor, as Tpo signalling is unimpaired in the presence of RX187. In contrast, the effects of IL-3 on CFU-Meg growth are mediated in part through Tpo and through gp130-signalling cytokines.  相似文献   
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Olfactory receptors (ORs) comprise more than half of the large class I G protein-coupled receptor (GPCR) superfamily. Although cloned over a decade ago, little is known about their properties because wild-type ORs do not efficiently reach the cell surface following heterologous expression. Receptor-receptor interactions strongly influence surface trafficking of other GPCRs, and we examined whether a similar mechanism might be involved in OR surface expression. Olfactory neurons are known to express beta-adrenergic receptors (ARs), and we found that coexpression with beta(2)-ARs, but not any other AR subtypes, dramatically increased mouse 71 (M71) OR surface expression in human embryonic kidney 293 cells. A persistent physical interaction between M71 ORs and beta(2)-ARs was shown by coimmunoprecipitation and by cointernalization of the two receptors in response to their specific ligands. Also, coexpression of wild-type M71 ORs with beta(2)-ARs resulted in cAMP responses to the M71 ligand acetophenone. Finally, in situ hybridization studies showed extensive colocalization of M71 OR and beta(2)-AR expression in mouse olfactory epithelium. These data demonstrate the successful heterologous surface expression of a functional wild-type OR and reveal that persistent physical association with other GPCRs can control OR surface expression.  相似文献   
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Haemorrhagic septicaemia (HS) is an acute fatal infectious disease of mainly cattle and buffalo and outbreaks occur commonly in Cambodia. Disease outbreak reports were examined to select five villages from three provinces for a retrospective investigation of HS epidemiology and socioeconomic impact on smallholders, with an aim of identifying potential benefits from improving disease prevention through biosecurity and vaccination. The Village Animal Health Worker (VAHW) or Chief in each village and 66 affected smallholders were surveyed. At the village level, 24% of all households were affected with an estimated mean village herd morbidity of 10.1% and mortality of 28.8%. Affected farmers reported HS disease morbidity and mortality at 42.7% and 63.6% respectively. Buffalo had a higher morbidity (OR = 2.3; = 0.003) and mortality (OR = 6.9; < 0.001) compared with cattle, and unvaccinated large ruminants a higher morbidity (OR = 2.9; = 0.001). The financial impact varied depending on whether the animal survived, provision of treatment, draught replacement and lost secondary income. The mean cost per affected household was USD 952.50 based on ownership of five large ruminants. The impact per affected animal was USD 375.00, reducing the pre‐disease value by 66.1%. A partial budget revealed an overwhelming incentive for farmers to practice biannual vaccination, with a net benefit of USD 951.58 per household based on an annual disease incidence rate of 1. Sensitivity analysis showed that a net benefit of USD 32.42 remained based on an outbreak every 20 years. This study indicates HS can cause a catastrophic financial shock to smallholders and remains a critical constraint to improving large ruminant productivity and profitability. Addressing HS disease control requires a focus on improving smallholder farmer knowledge of biosecurity and vaccination and should be priority to stakeholders interested in addressing regional food insecurity and poverty reduction.  相似文献   
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Childhood asthma is a huge global health burden. The spectrum of disease, diagnosis, and management vary depending on where children live in the world and how their community can care for them. Global improvement in diagnosis and management has been unsatisfactory, despite ever more evidence‐based guidelines. Guidelines alone are insufficient and need supplementing by government support, changes in policy, access to diagnosis and effective therapy for all children, with research to improve implementation. We propose a worldwide charter for all children with asthma, a roadmap to better education and training which can be adapted for local use. It includes access to effective basic asthma medications. It is not about new expensive medications and biologics as much can be achieved without these. If implemented carefully, the overall cost of care is likely to fall and the global future health and life chance of children with asthma will greatly improve. The key to success will be community involvement together with the local and national development of asthma champions. We call on governments, institutions, and healthcare services to support its implementation.  相似文献   
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