A critical role for eosinophils in allergic airways remodeling

Features of chronic asthma include airway hyperresponsiveness, inflammatory infiltrates, and structural changes in the airways, termed remodeling. The contribution of eosinophils, cells associated with asthma and allergy, remains to be established. We show that in mice with a total ablation of the eosinophil lineage, increases in airway hyperresponsiveness and mucus secretion were similar to those observed in wild-type mice, but eosinophil-deficient mice were significantly protected from peribronchiolar collagen deposition and increases in airway smooth muscle. These data suggest that eosinophils contribute substantially to airway remodeling but are not obligatory for allergen-induced lung dysfunction, and support an important role for eosinophil-targeted therapies in chronic asthma.     

A critical role for murine complement regulator crry in fetomaternal tolerance

Complement is a component of natural immunity. Its regulation is needed to protect tissues from inflammation, but mice with a disrupted gene for the complement regulator decay accelerating factor were normal. Mice that were deficient in another murine complement regulator, Crry, were generated to investigate its role in vivo. Survival of Crry-/- embryos was compromised because of complement deposition and concomitant placenta inflammation. Complement activation at the fetomaternal interface caused the fetal loss because breeding to C3-/- mice rescued Crry-/- mice from lethality. Thus, the regulation of complement is critical in fetal control of maternal processes that mediate tissue damage.     

A critical role for the innate immune signaling molecule IRAK-4 in T cell activation

IRAK-4 is a protein kinase that is pivotal in mediating signals for innate immune responses. Here, we report that IRAK-4 signaling is also essential for eliciting adaptive immune responses. Thus, in the absence of IRAK-4, in vivo T cell responses were significantly impaired. Upon T cell receptor stimulation, IRAK-4 is recruited to T cell lipid rafts, where it induces downstream signals, including protein kinase C activation through the association with Zap70. This signaling pathway was found to be required for optimal activation of nuclear factor kappaB. Our findings suggest that T cells use this critical regulator of innate immunity for the development of acquired immunity, suggesting that IRAK-4 may be involved in direct signal cross talk between the two systems.     

A chromosome 21 critical region does not cause specific Down syndrome phenotypes

The "Down syndrome critical region" (DSCR) is a chromosome 21 segment purported to contain genes responsible for many features of Down syndrome (DS), including craniofacial dysmorphology. We used chromosome engineering to create mice that were trisomic or monosomic for only the mouse chromosome segment orthologous to the DSCR and assessed dysmorphologies of the craniofacial skeleton that show direct parallels with DS in mice with a larger segmental trisomy. The DSCR genes were not sufficient and were largely not necessary to produce the facial phenotype. These results refute specific predictions of the prevailing hypothesis of gene action in DS.     

HIV/AIDS患者外周血中4种细胞因子IL-2、IL-4、IL-15和IL-21表达水平及其临床意义研究

目的 观察外周血 4 种细胞因子（IL-2、IL-4、IL-15及IL-21）在HIV感染者/AIDS患者（HIV/AIDS）和正常人表达水平的区别及其与HIV RNA病毒载量和CD3⁺、CD4⁺细胞数量的相关性,分析其与HIV感染的关系和临床意义。方法 40例未经抗病毒治疗的HIV/AIDS 和31名正常人,采用ELISA法检测外周血4种细胞因子（IL-2、IL-4、IL-15及IL-21）,使用流式细胞计数法检测外周血CD3⁺、CD4⁺ T 淋巴细胞数量,实时聚合酶链反应测定血清中HIV RNA水平。结果 未经抗病毒治疗的HIV/AIDS外周血IL-2、IL-15及IL-21水平低于正常人,而IL-4水平高于正常人（P<0.05）。CD3⁺、CD4⁺细胞数量和各细胞因子水平显示出一定的相关关系,IL-2和IL-15水平均与HIV-1 RNA载量呈负相关。结论 提示外周血4种细胞因子都可能参与了HIV感染的致病机制,并与HIV RNA病毒载量及CD3⁺、CD4⁺细胞数量相关。     

21世纪养猪生产中的营养及饲养技术策略

21世纪养猪生产的目标是优质、高效、无公害。围绕这一目标，本文论述了猪营养与饲养技术领域拟采取的技术策略：（1）通过养猪新工艺和绿色饲料的应用，确保猪肉产品的卫生安全性；（2）通过营养调控技术改善肉质风味；（3）通过理想蛋白质和酶调控技术提高饲料转化率并实现低污染、低公害生产。     

玉米制种花期预测与调控二十法

就玉米花期相遇问题进行了相关的试验、研究与分析 ,根据玉米生长发育速度、幼穗分化进程等进行了科学预测 ,并对花期相遇差的玉米通过栽、管、割、化、摸、剪、辅等相应的技术措施进行调控 ,科学总结出 2 0条预测、调控花期新技术 ,为今后玉米制种确保花期如期相遇提供了技术保障。     

出口清蒸牛肉罐头生产过程中关键控制点的选择

按照良好生产规范、卫生标准操作规程、危害分析和关键控制点的要求，对清蒸牛肉罐头生产过程中可能影响产品品质及食品安全的因素进行分析，确定相应的关键控制点，探索生产安全罐头食品的必要条件。     

河北省种植业结构调整决策支持系统研究

为了使河北省的种植业结构调整更加理性化和规范化,增加结构调整的可操作性,应用系统动力学模型设计了种植业结构调整决策支持系统,以科学、理性地调整河北省种植业结构。在本系统中输入作物播种面积、产量、价格等相关数据后,就可以得到既定结构下河北省的种植业总产值。     

Neuroscience. A critical issue for the brain

The notion that there is a "critical period" for learning in the first 3 years of life has cropped up widely in media reports recently. But although critical periods have been well documented for the development of sensory systems in the brain, especially vision, researchers differ over whether they exist for the development of the brain functions that underlie complex learning and thinking skills. Scientists do agree, however, that where critical periods do exist, they are not sharply defined, nor are they unique to the first 3 years of life, as has been conveyed in the media. The message should give hope to adults who may not learn with the ease of early childhood, but can still do it.     

mTOR信号通路在调控猪繁殖与呼吸综合征病毒复制中的作用

[目的]为阐明哺乳动物雷帕霉素靶点(mammalian target of Rapamycin,mTOR)信号通路在调控猪繁殖与呼吸综合征病毒(porcine reproductive and respiratory syndrome virus,PRRSV)复制过程中的作用,探索防控该病传染的新途径.[方法]PRRS...