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21.
The commensal microbiota has emerged as an environmental risk factor for multiple sclerosis (MS). Studies in experimental autoimmune encephalomyelitis (EAE) models have shown that the commensal microbiota is an essential player in triggering autoimmune demyelination. Likewise, the commensal microbiota modulates the host immune system, alters the integrity and function of biological barriers and has a direct effect on several types of central nervous system (CNS)-resident cells. Moreover, a characteristic gut dysbiosis has been recognized as a consistent feature during the clinical course of MS, and the MS-related microbiota is gradually being elucidated. This review highlights animal studies in which commensal microbiota modulation was tested in EAE, as well as the mechanisms of action and influence of the commensal microbiota not only in the local milieu but also in the innate and adaptive immune system and the CNS. Regarding human research, this review focuses on studies that show how the commensal microbiota might act as a pathogenic environmental risk factor by directing immune responses towards characteristic pathogenic profiles of MS. We speculate how specific microbiome signatures could be obtained and used as potential pathogenic events and biomarkers for the clinical course of MS. Finally, we review recently published and ongoing clinical trials in MS patients regarding the immunomodulatory properties exerted by some microorganisms. Because MS is a complex disease with a large variety of associated environmental risk factors, we suggest that current treatments combined with strategies that modulate the commensal microbiota would constitute a broader immunotherapeutic approach and improve the clinical outcome for MS patients.  相似文献   
22.
李清  李解方  杨金瑞 《肿瘤防治研究》2007,34(11):858-859,863
 目的 探索DNA倍体类型、细胞周期在前列腺上皮内瘤中诊断和鉴别诊断的价值。方法 应用细胞图像分析技术检测前列腺上皮内瘤(PIN)细胞的平均DNA含量、DNA平均倍体值及细胞周期的各个时相的变化。同时与良性前列腺增生症(BPH)、前列腺癌(PCa)比较。结果 PIN组异倍体率为70%,前列腺上皮内瘤DNA平均倍体值、G0/G1期细胞比率、S期细胞比率介于良性前列腺增生症和前列腺癌之间。结论 DNA异倍体、较高S期细胞比率是前列腺上皮内瘤重要生物学特性。对于前列腺上皮内瘤的鉴别诊断具有一定参考价值。  相似文献   
23.
Since 2012, H7N3 highly pathogenic avian influenza (HPAI) has produced negative economic and animal welfare impacts on poultry in central Mexico. In the present study, chickens were vaccinated with two different recombinant fowlpox virus vaccines (rFPV-H7/3002 with 2015 H7 hemagglutinin [HA] gene insert, and rFPV-H7/2155 with 2002 H7 HA gene insert), and were then challenged three weeks later with H7N3 HPAI virus (A/chicken/Jalisco/CPA-37905/2015). The rFPV-H7/3002 vaccine conferred 100% protection against mortality and morbidity, and significantly reduced virus shed titers from the respiratory and gastrointestinal tracts. In contrast, 100% of sham and rFPV-H7/2155 vaccinated birds shed virus at higher titers and died within 4?days. Pre- (15/20) and post- (20/20) challenge serum of birds vaccinated with rFPV-H7/3002 had antibodies detectable by hemagglutination inhibition (HI) assay using challenge virus antigen. However, only a few birds (3/20) in the rFPV-H7/2155 vaccinated group had antibodies that reacted against the challenge strain but all birds had antibodies that reacted against the homologous vaccine antigen (A/turkey/Virginia/SEP-66/2002) (20/20). One possible explanation for differences in vaccines efficacy is the antigenic drift between circulating viruses and vaccines. Molecular analysis demonstrated that the Mexican H7N3 strains have continued to rapidly evolve since 2012. In addition, we identified in silico three potential new N-glycosylation sites on the globular head of the H7 HA of A/chicken/Jalisco/CPA-37905/2015 challenge virus, which were absent in 2012 H7N3 outbreak virus. Our results suggested that mutations in the HA antigenic sites including increased glycosylation sites, accumulated in the new circulating Mexican H7 HPAIV strains, altered the recognition of neutralizing antibodies from the older vaccine strain rFPV-H7/2155. Therefore, the protective efficacy of novel rFPV-H7/3002 against recent outbreak Mexican H7N3 HPAIV confirms the importance of frequent updating of vaccines seed strains for long-term effective control of H7 HPAI virus.  相似文献   
24.
解放军疾病预防控制所,为履行职能和任务,在业务办公大楼12层建设了SPF动物实验设施,面积约240 m2。文章介绍了作者的设计思路和建设方案。同时还介绍了SPF动物房的建设经验。  相似文献   
25.
Simian betaretroviruses (formerly Type D retroviruses; SRV) are a group of closely related retroviruses for which the natural host species are Asian monkeys of the genus Macaca. Five serotypes have been identified by classical neutralization assays and three additional untyped variants have been reported (SRVTsukuba, SRV-6, SRV-7). These viruses may be significant pathogens in macaque colonies, causing a broad spectrum of clinical disease secondary to viral-induced immune suppression. Undetected SRV infections in research macaques also represent a potential confounding variable in research protocols and a concern for human caretakers. Intensive testing efforts have been implemented to identify infected animals in established colonies. A real-time quantitative generic multiplex PCR assay was developed that is capable of simultaneous detection of proviral DNA of SRV serotypes 1, 2, 3, 4 and 5. This assay incorporates amplification of the oncostatin M (OSM) gene for confirmation of amplifiable DNA and allows quantitation of the number of proviral copies per cell analyzed in each multiplex reaction. Detection of multiple serotypes by PCR increases the efficiency and cost-effectiveness of SRV screening programs. A panel of SRV serotype-specific uniplex real-time PCR assays for discrimination among the five recognized serotypes is also described.  相似文献   
26.
The efficacy of different vaccination schedules was evaluated in 17-day-old Pekin ducks using an experimental inactivated whole virus vaccine based on the H5N9 A/chicken/Italy/22A/98 isolate (H5N9-It) and/or a fowlpox recombinant (vFP-H5) expressing a synthetic HA gene from an Asian H5N1 isolate (A/chicken/Indonesia/7/2003). Full protection against clinical signs and shedding was induced by the different vaccination schemes. However, the broadest antibody response and the lowest antibody increase after challenge were observed in the group of ducks whose immune system was primed with the fowlpox vectored vaccine and boosted with the inactivated vaccine, suggesting that this prime-boost strategy induced optimal immunity against H5N1 and minimal viral replication after challenge in ducks. In addition, this prime-boost vaccination scheme was shown to be immunogenic in 1-day-old ducklings.  相似文献   
27.
Background The sun protection factor (SPF) of sunscreens is determined after application of a standard amount. The European Cosmetic Toiletry and Perfumery Association (COLIPA) standard amount is 2 mg/cm2. Real‐life application of sunscreen is probably less than this. Aim To determine the amount of sunscreen present on the skin of people at the beach. Methods Volunteers at the beach were selected randomly and were not aware of being tested for the adequacy of their sunscreen application. All volunteers had applied sunscreen. Application had been more than 30 min before testing (sometimes up to 4 h earlier). The amounts of sunscreen applied to different body sites were determined quantitatively by tape stripping. Actual amounts of sunscreen applied were compared with the COLIPA standard. Also, sunscreen containing a fluorescent dye was applied to the skin of volunteers in a laboratory setting. The distribution of sunscreen application was visualized by UVA photography in a darkened room. Results Sixty volunteers, 33 males and 27 females, aged 17–68 years (median 32 years), were recruited at the beach. Sunscreen coverage was inadequate at all body sites. Coverage at various body sites differed greatly. Most volunteers had applied 10% or less of the COLIPA standard amount to all body sites assessed. The best protected areas were the upper arm and décolleté but, even in these areas, most volunteers had only applied 10% of the COLIPA standard amount. The worst protected areas were the ears and top of the feet. The back was typically badly protected if treated by the volunteers themselves. The back was better protected if another person had applied the sunscreen. In the laboratory, the fluorescent dye‐containing sunscreen showed the same pattern of sunscreen application as at the beach. Conclusions In real life, at the beach, very little sunscreen remains present on the skin.  相似文献   
28.
QFGJS is an herbal preparation, and its pronounced effectiveness in treating adjuvant-induced arthritis (AIA) has been previously demonstrated. We herein aimed to confirm its anti-arthritic effect on collagen-induced arthritis (CIA) in rats. CIA was established in female Wistar rats with intradermal injection of type II bovine collagen at the base of the tail of animals. CIA rats were treated daily with oral administration of different doses of QFGJS beginning on the day of the induction of arthritis (day 0, the prophylactic treatment) or on the day after the onset of arthritis (day 13, the therapeutic treatment) until day 30. The results showed that prophylactic treatment with QFGJS significantly suppressed the onset of arthritis, and therapeutic treatment with QFGJS markedly reduced paw swelling and ESR levels even in the established CIA. Radiologic and histopathologic changes in the arthritic joints were also significantly reduced in the QFGJS-treated versus vehicle-treated rats. Moreover, the serum levels of pro-inflammatory cytokines TNF-alpha, IL-1beta, and IL-6 were markedly lowered in the QFGJS-treated rats. Hence, our studies demonstrate the quality, safety, and effectiveness of QFGJS as an anti-arthritic agent, which makes QFGJS a strong candidate for further clinical trials on rheumatoid arthritis (RA) patients.  相似文献   
29.
SPF级实验动物设施的建立和管理进行初步探讨。设计原则SPF级实验动物生产饲养和实验饲养设施条件配套,人、物、动物、空气流的工艺流程合理。  相似文献   
30.
目的了解原发性肺癌组织中DNA倍体,SPF、PI值与临床分期的关系。方法应用流式细胞仪(FCM)测定石蜡包埋的原发性肺癌组织标本80例,检测DNA倍体,SPF、PI值。结果随着原发性肺癌临床分期的发展,临床Ⅰ~Ⅱ与Ⅲ~Ⅳ期肿瘤的异倍体率(Ⅰ~Ⅱ期35%,Ⅲ~Ⅳ期47.5%),SPF、PI值均增高,其与正常肺组织均有显著性统计学差异。但肿瘤各临床分期Ⅰ~Ⅱ与Ⅲ~Ⅳ期之间并无统计学意义。结论测定原发性肺癌组织的DNA倍体,SPF、PI值能了解肺癌某些分子生物学特性,从而从分子水平上了解其增殖活性。对肿瘤的诊断及预后的评估有积极的临床意义。  相似文献   
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