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11.
《Vaccine》2020,38(1):20-28
During the last few decades, maternal immunization as a strategy to protect young infants from infectious diseases has been increasingly recommended, yet some issues have emerged. Studies have shown that for several vaccines, such as live attenuated, toxoid and conjugated vaccines, high maternal antibody titers inhibit the infant’s humoral immune response after infant vaccination. However, it is not clear whether this decreased antibody titer has any clinical impact on the infant’s protection, as the cellular immune responses are often equally important in providing disease protection and may therefore compensate for diminished antibody levels. Reports describing the effect of maternal antibodies on the cellular immune response after infant vaccination are scarce, probably because such studies are expensive, labor intensive and utilize poorly standardized laboratory techniques. Therefore, this review aims to shed light on what is currently known about the cellular immune responses after infant vaccination in the presence of high (maternal) antibody titers both in animal and human studies. Overall, the findings suggest that maternally derived antibodies do not interfere with the cellular immune responses after infant vaccination. However, more research in humans is clearly needed, as most data originate from animal studies.  相似文献   
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The distribution of epigenetic alterations, such as DNA methylation and histone modifications, is abnormal in cancer cells, and drugs that influence these changes are currently being used effectively in the treatment of hematopoietic malignancies. Two hypomethylating agents, 5-azacytidine and decitabine, are FDA-approved for the treatment of myelodysplastic syndromes, and one histone deacetylase inhibitor, vorinostat, was recently FDA-approved for patients with refractory cutaneous T-cell lymphoma. Generally, these agents are very well tolerated, with myelosuppression being the major side effect. Although they are thought to work by re-organizing chromatin to allow expression of genes silenced by DNA hypermethylation and repressive histone modifications, the precise mechanism of action of these agents is not yet clear. Current studies are examining the utility of these agents for the treatment of solid tumors as well as testing these drugs in combination to treat a variety of malignancies.  相似文献   
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Since the triggering factors causing primary vasculitides are by definition not (yet) known, we have to classify them to clinical syndromes based on the size, site, type and effect of the blood vessel involvement. ACR classification criteria and Chapel Hill nomenclature are useful tools to familiarize with the primary vasculitides, although a lot of criticism has been voiced in the literature indicating that they only represent the best available consensus. The present text takes advantage of the recent developments such as introduction of the anti-neutrophilic cytoplasmic auto (ANCA) antibodies, and divides the vasculitides to those affecting typically the large, medium and small arteries or only small blood vessels. In addition, some vasculitides, which are still difficult to place to the vasculitis map, like Bürger's disease, Goodpasture's syndrome, primary angiitin of the central nervous system (PACNS) and panniculitis, are dealt with. As it is a long and winding road, attention has to be paid to the clinical details to follow the road sign to “pseudovasculitis”, when that is the right way to go. They represent a bunch of non-vasculitic conditions, which lead to structural or vasospastic impairment of the blood flow, bleeding or thromboembolism and hyperviscosity. These imitators have to some extent, similar clinical symptoms and signs as well as laboratory and radiological findings to those found in true systemic vasculitides. This also emphasizes the importance of internal medicine as the intellectual (albeit not necessarily organizational) home of rheumatology and rheumatologists as we deal with conditions like atherosclerosis, antiphospholipid antibody syndrome, infectious endocarditic, myxoma of the heart and cholesterol embolism.  相似文献   
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目的:探讨人胰腺导管腺癌组织和癌旁组织之间差异的表达蛋白。方法:利用双向凝胶电泳(2-DE)对8例胰腺导管腺癌组织和癌旁组织的总蛋白进行分离,并用质谱仪对两组间差异蛋白质点进行肽指纹谱和串联质谱鉴定。利用蛋白质印迹分析和免疫组化法检测差异蛋白在胰腺癌和癌旁组织的表达。结果:2-DE显示,肿瘤组织中有28个蛋白质点表达上调,17个表达下调。上述蛋白质点经质谱鉴定得到30个蛋白质,包括酶类、抗氧化蛋白、信号转导蛋白、钙结合蛋白、结构蛋白及分子伴侣等。Western blot和免疫组化结果显示差异表达蛋白annexin II在胰腺癌组织中表达上调,与2-DE结果一致。结论:以2-DE为基础的蛋白质组学技术是研究肿瘤的一种重要手段。本实验所得的annexin II等差异表达蛋白可能成为潜在的诊断胰腺癌的分子标志或控制肿瘤生长的治疗靶点。  相似文献   
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The recent global resurgence of mumps has drawn attention to the continued need for robust mumps immunization programs. Unfortunately, some vaccines derived from inadequately attenuated vaccine strains of mumps virus have caused meningitis in vaccinees, leading to withdrawal of certain vaccine strains from the market, public resistance to vaccination, or in some cases, cessation of national mumps vaccination programs. The most widely implicated mumps vaccine in cases of postvaccination meningitis is derived from the Urabe AM9 strain, which remains in use in some countries. The Urabe AM9 vaccine virus has been shown to exhibit a considerable degree of nucleotide and amino acid heterogeneity. Some studies have specifically implicated variants containing a lysine residue at amino acid position 335 in the hemagglutinin-neuraminidase (HN) protein with neurotoxicity, whereas a glutamic acid residue at this position was associated with attenuation. To test this hypothesis we generated two modified Urabe AM9 cDNA clones coding either for a lysine or a glutamic acid at position 335 in the HN gene. The two viruses were rescued by reverse genetics and characterized in vitro and in vivo. Both viruses exhibited similar growth kinetics in neuronal and non-neuronal cell lines and were of similar neurotoxicity when tested in rats, suggesting that amino acid 335 is not a crucial determinant of Urabe AM9 growth or neurovirulence.  相似文献   
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