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1.
The influence of home environmental factors and life style on children's respiratory health in Xi'an
To assess associations between home indoor air environments and asthma,allergies and pneumonia,children aged 1–8 years were surveyed from 12 kindergartens in the city of Xi’an.2,020 questionnaires were responded with a response rate of 83.5%.The prevalences of doctor diagnosed asthma,hay fever,and pneumonia were 2.9%,3.6%,and 28.3%,respectively.Living close to a highway was a risk factor for current rhinitis(AOR 1.5,95%CI 1.2–1.8),eczema(AOR 1.7,95%CI 1.2–2.5),and diagnosed pneumonia(AOR 1.3,95%CI 1.0–1.6).Dampness problems in the home were associated with 50%–130%increases in the prevalences of asthma and allergy.Airing bed linen under sun-shine was protective,especially against rhinitis.Pet avoidance was consistently and significantly associated with asthma and allergy(AOR 1.3–2.4).Decoration of the home during children’s early life is a risk factor for current rhinitis(AOR 1.9,95%CI 1.3–2.9)and eczema(AOR 1.9,95%CI1.1–3.6).Risk factors for pneumonia were living in an apartment(AOR 1.4,95%CI 1.1–1.8),latex wall paint(AOR 1.3,95%CI 1.0–1.7),dampness(AOR 1.4–1.5),breast feeding\3 months(AOR 1.3,95%CI 1.0–1.7),never airing bed linen in sunshine(AOR 1.3,95%CI1.3–1.6),and cleaning children’s room less frequently than once per day(AOR 1.4,95%CI 1.1–1.7).This study demonstrates that home indoor environmental and life style factors may influence the health of children in Xi’an. 相似文献
2.
Isaak Quast Benjamin Peschke Jan D. Lünemann 《Cellular and molecular life sciences : CMLS》2017,74(5):837-847
Immunoglobulin gamma (IgG) antibodies are key effector proteins of the immune system. They recognize antigens with high specificity and are indispensable for immunological memory following pathogen exposure or vaccination. The constant, crystallizable fragment (Fc) of IgG molecules mediates antibody effector functions such as complement-dependent cytotoxicity, antibody-mediated cellular cytotoxicity, and antibody-dependent cell-mediated phagocytosis. These functions are regulated by a single N-linked, biantennary glycan of the heavy chain, which resides just below the hinge region, and the presence of specific sugar moieties on the glycan has profound implications on IgG effector functions. Emerging knowledge of how Fc glycans contribute to IgG structure and functions has opened new avenues for the therapeutic exploitation of defined antibody glycoforms in the treatment of cancer and autoimmune diseases. Here, we review recent advances in understanding proinflammatory IgG effector functions and their regulation by Fc glycans. 相似文献
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Vedrana Filić Maja Marinović Jan Faix Igor Weber 《Cellular and molecular life sciences : CMLS》2014,71(15):2775-2785
Proteins are typically categorized into protein families based on their domain organization. Yet, evolutionarily unrelated proteins can also be grouped together according to their common functional roles. Sequestering proteins constitute one such functional class, acting as macromolecular buffers and serving as an intracellular reservoir ready to release large quantities of bound proteins or other molecules upon appropriate stimulation. Another functional protein class comprises effector proteins, which constitute essential components of many intracellular signal transduction pathways. For instance, effectors of small GTP-hydrolases are activated upon binding a GTP-bound GTPase and thereupon participate in downstream interactions. Here we describe a member of the IQGAP family of scaffolding proteins, DGAP1 from Dictyostelium, which unifies the roles of an effector and a sequestrator in regard to the small GTPase Rac1. Unlike classical effectors, which bind their activators transiently leading to short-lived signaling complexes, interaction between DGAP1 and Rac1-GTP is stable and induces formation of a complex with actin-bundling proteins cortexillins at the back end of the cell. An oppositely localized Rac1 effector, the Scar/WAVE complex, promotes actin polymerization at the cell front. Competition between DGAP1 and Scar/WAVE for the common activator Rac1-GTP might provide the basis for the oscillatory re-polarization typically seen in randomly migrating Dictyostelium cells. We discuss the consequences of the dual roles exerted by DGAP1 and Rac1 in the regulation of cell motility and polarity, and propose that similar signaling mechanisms may be of general importance in regulating spatiotemporal dynamics of the actin cytoskeleton by small GTPases. 相似文献
4.
Irina Kerkis Alvaro Rossan de Brandão Prieto da Silva Celine Pompeia Jan Tytgat Paulo L. de Sá Junior 《Cellular and molecular life sciences : CMLS》2017,74(4):647-661
Toxins have been shown to have many biological functions and to constitute a rich source of drugs and biotechnological tools. We focus on toxins that not only have a specific activity, but also contain residues responsible for transmembrane penetration, which can be considered bioportides—a class of cell-penetrating peptides that are also intrinsically bioactive. Bioportides are potential tools in pharmacology and biotechnology as they help deliver substances and nanoparticles to intracellular targets. Bioportides characterized so far are peptides derived from human proteins, such as cytochrome c (CYCS), calcitonin receptor (camptide), and endothelial nitric oxide synthase (nosangiotide). However, toxins are usually disregarded as potential bioportides. In this review, we discuss the inclusion of some toxins and molecules derived thereof as a new class of bioportides based on structure activity relationship, minimization, and biological activity studies. The comparative analysis of the amino acid residue composition of toxin-derived bioportides and their short molecular variants is an innovative analytical strategy which allows us to understand natural toxin multifunctionality in vivo and plan novel pharmacological and biotechnological products. Furthermore, we discuss how many bioportide toxins have a rigid structure with amphiphilic properties important for both cell penetration and bioactivity. 相似文献
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论述了随着教学改革的不断深入,在大学数学课堂教学中分析学生心理因素的重要性,应用模糊数学中二元对比排序法对其不同时刻的心理因素活动建立了动态轨迹,并用模糊熵分析各因素的重要程度,以此优化数学课堂教学. 相似文献
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Two new studies report mutations in FAN1 and three other genome-stability genes that tie the DNA damage response to progressive kidney failure and the dysfunction of several other organs. These findings provide clues to the underlying causes of tissue decline and may add a series of genes to the growing list of genome maintenance factors that protect against premature aging. 相似文献
10.
The prevalence and risk factors of sick building syndrome(SBS)symptoms in domestic environments were studied by a questionnaire survey on the home environment.Parents of 5299 3–6 years old children from randomly selected kindergartens in Chongqing,China returned completed questionnaires between December 2010 and April 2011.The prevalence of parents’SBS symptoms(often(every week)compared with never)were:11.4%for general symptoms,7.1%for mucosal symptoms and 4.4%for skin symptoms.Multiple logistic regressions were applied controlling for gender and asthma/allergic rhinitis/eczema.Living near a main road or highway was a strong risk factor for general symptoms(adjusted odds ratio,aOR=2.16,P<0.001),skin symptoms(aOR=2.69,P<0.001),and mucosal symptoms(aOR=1.63,P<0.01).Redecoration was a risk factor for general symptoms(aOR=2.00,P<0.001),skin symptoms(aOR=1.66,P<0.01),and mucosal symptoms(aOR=1.66,P<0.05).New furniture was a risk factor for general symptoms(aOR=2.16,P<0.001)and skin symptoms(aOR=1.67,P<0.01).Dampness related problems(mould spot,damp stain,water damage and condensation)were all risk factors for SBS symptoms,as was the presence of cockroaches,rats,and mosquitoes/flies and use of incense.Protective factors include cleaning the child’s bedroom every day and frequently exposing bedding to sunshine.In conclusion,adults’SBS symptoms were related to factors of the home environment. 相似文献