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141.
目的 建立适合SPF猕猴种群建立与保持所需的B病毒抗体监测模式。方法 采用BV EIA及BVELISA等方法对本中心自繁自育仔猴从断奶开始进行BV感染情况跟踪。结果 从自繁自育猴中随机挑选218只断奶食蟹猴,92只断奶猕猴,经过近两年反复筛选得到25只SPF食蟹猴,9只SPF猕猴,此结果经美国BioReliatnce公司检测得到确认。结论 该模式能有效监测猕猴BV抗体变化,为本中心在国内建立猕猴SPF种群提供了有力的技术保障。  相似文献   
142.
Increased polyamine production is observed in a variety of chronic neuroinflammatory disorders, but in vitro and in vivo studies yield conflicting data on the immunomodulatory consequences of their production. Ornithine decarboxylase (ODC) is the rate-limiting enzyme in endogenous polyamine production. To identify the role of polyamine production in CNS-intrinsic inflammatory responses, we defined CNS sites of ODC expression and the consequences of inhibiting ODC in response to intracerebral injection of LPS ± IFNγ. In situ hybridization analysis revealed that both neurons and non-neuronal cells rapidly respond to LPS ± IFNγ by increasing ODC expression. Inhibiting ODC by co-injecting DFMO decreased LPS-induced CCL2 expression and macrophage influx into the CNS, without altering LPS-induced microglial or macrophage activation. Conversely, intracerebral injection of polyamines was sufficient to trigger macrophage influx into the CNS of wild-type but not CCL2KO mice, demonstrating the dependence of macrophage influx on CNS expression of CCL2. Consistent with these data, addition of putrescine and spermine to mixed glial cultures dramatically increased CCL2 expression and to a much lesser extent, TNF expression. Addition of all three polyamines to mixed glial cultures also decreased the numbers and percentages of oligodendrocytes present. However, in vivo, inhibiting the basal levels of polyamine production was sufficient to induce expression of apolipoprotein D, a marker of oxidative stress, within white matter tracts. Considered together, our data indicate that: (1) CNS-resident cells including neurons play active roles in recruiting pro-inflammatory TREM1-positive macrophages into the CNS via polyamine-dependent induction of CCL2 expression and (2) modulating polyamine production in vivo may be a difficult strategy to limit inflammation and promote repair due to the dual homeostatic and pro-inflammatory roles played by polyamines.  相似文献   
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144.
The purpose of this research is to study the effect of sulfated lentinan (sLNT) on immune effect of Newcastle disease (ND) vaccine. In immune response test, 14-day-old chickens were vaccinated with ND vaccine then grouped respectively to inject three sLNTs at two doses, once a day for three successive days, taking non-sulfated lentinan (LNT) as the control. The changes of serum antibody titer and peripheral lymphocyte proliferation were determined before and after vaccination. In immune protection test, 35-day-old chickens were challenged with ND virus (NDV) after treated similar to above mentioned. The morbidity and mortality of chickens were observed, and the changes of serum antibody titer and peripheral lymphocyte proliferation were measured before and after challenge. The results showed that three modified sLNTs could significantly enhance serum antibody titer and promote lymphocyte proliferation in two experimental chickens, and reduce morbidity and mortality of chickens challenged with NDV, which were better than that of non-modified LNT. Their high doses in enhancing antibody titer and low doses in promoting lymphocyte proliferation were more preferable. These results indicated that sulfated modification could enhance the adjuvanticity of LNT and improve the immune effect of ND vaccine. sLNT2 possessed the best efficacy and would be expected as the candidate of a new-type immune adjuvant.  相似文献   
145.
This study examined the effects of cholesterol on mouse intestinal microflora and on isoflavonoids in the cecum and plasma. Dietary cholesterol affects bile acid metabolism and bile acids can influence the intestinal microorganisms. Intestinal microflora appear to play an important role in isoflavone metabolism. We hypothesized that dietary cholesterol changes the metabolism of isoflavonoids and intestinal microorganisms in mice. Male mice were randomly divided into two groups, which were fed a cholesterol-daidzein (CDA) or daidzein (DA) diet (control diet) for 60d. Plasma equol and cecal equol concentrations were significantly higher in the DA group (control group) than in the CDA group. However, plasma cholesterol concentrations were significantly higher in the CDA group compared to the DA group. The composition of cecal microorganisms differed between the two dietary groups. The occupation ratios of Clostridium cluster XI, Clostridium subcluster XIVa, and Lactobacillales were significantly higher in the CDA group. The occupation ratio of Bifidobacterium was significantly lower in the CDA group. This study suggests that dietary cholesterol has the potential to affect the metabolism of equol from daidzein by altering the metabolic activity of the intestinal microorganisms and gut physiological function.  相似文献   
146.
Background/purpose: Recently, we showed that the sun protection factor (SPF) decreases by a constant factor to reach 55% during a day with activities. Organic sunscreens but not inorganic ones are absorbed through the skin. We wished to determine the SPF decrease caused by absorption by investigating the difference in SPF decreases between an organic and an inorganic sunscreen, assuming that the sunscreens are stable, and that the SPF decrease is time dependent if caused by absorption.
Methods: Sunscreens were used on the backs of 22 participants, who were physically inactive at 22 °C. SPF testing was performed 30 min, 4, and 8 h after application of 2 mg/cm2 sunscreen. Whether cream evaporation changed the ultraviolet (UV) transmission was studied in vitro .
Results: The SPFs of the organic and inorganic sunscreens were reduced by about 25% after 8 h. Evaporation of the cream did not cause a change in UV transmission in vitro .
Conclusion: A similar decrease in SPF of the organic and inorganic sunscreen was seen during 8 h without activities, and is thus not likely to be caused by absorption or evaporation from the skin. The SPF decrease after 8 h is about 55% when the participants perform activities and 25% without activities.
Trial registration: Registered at http://www.clinicaltrials.gov . Register name: 'Sunscreen: Persistence of Sun Protection Factor and the Influence on Vitamin D'. Register number H-B-2007-120.  相似文献   
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148.

Ethnopharmacological relevance

Artemisia capillaris and Artemisia iwayomogi, both members of the Compositae family, have been indiscriminately used for various liver disorders as traditional hepatotherapeutic medicines in Korea for many years.

Aim of the study

In this study, the anti-hepatofibrotic effects of Artemisia capillaris and Artemisia iwayomogi were comparatively analyzed using a carbon tetrachloride (CCl4)-induced liver fibrosis rat model.

Materials and methods

Hepatic fibrosis was induced via a 10-week course of intraperitoneal CCl4 injections (50% dissolved in olive oil, 2 mL/kg, twice per week). Water extract of Artemisia capillaris (AC) or Artemisia iwayomogi (AI) was orally administered six times per week from the 5th to the 10th week.

Results

AI (50 mg/kg) significantly attenuated the CCl4-induced excessive release of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP) in serum (p < 0.05), and hydroxyproline and malondialdehyde (MDA) contents in liver tissue (p < 0.05). Further, AI markedly ameliorated the depletion of total antioxidant capacity (TAC), glutathione (GSH), and superoxide dismutase (SOD) in liver tissue (p < 0.01). Unexpectedly, AC did not exert any effects on the above parameters. Histopathological and immunohistochemical analyses revealed that AI drastically reduced inflammation, necrosis, fatty infiltration, collagen accumulation, and activation of hepatic satellite cells in liver tissue. These changes were not observed with AC treatment. Several critical genes of fibrosis-related cytokines including transforming growth factor beta (TGF-β), platelet-derived growth factor beta (PDGF-β), and alpha smooth muscle actin (α-SMA) were more prominently downregulated by AI compared to AC treatment.

Conclusion

Our results show that AI exerts greater hepatoprotective and anti-fibrotic effects as compared with AC via enhancing antioxidant capacity and downregulating fibrogentic cytokines.  相似文献   
149.
目的 了解原发性肝癌组织中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肝细胞癌组织标本120例,检测DNA倍体,SPF、PI值。结果随着原发性肝细胞癌临床分期的发展,临床Ⅰ~Ⅱ与Ⅲ~Ⅳ期肿瘤的异倍体率(Ⅰ~Ⅱ33.3%,Ⅲ-Ⅳ期42.8%),SPF、PI值均增高,其与正常肝组织均有统计学意义。但肿瘤各临床分期Ⅰ-Ⅱ与Ⅲ-Ⅳ期之间并无统计学意义。结论测定原发性肝细胞癌组织的DNA倍体,SPF、PI值能了解其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   
150.
《Gut microbes》2013,4(6):536-543
Laboratory rodents have been instrumental in helping researchers to unravel the complex interactions that mammals have with their microbial commensals. Progress in defining these interactions has also been possible thanks to the development of culture-independent methods for describing the microbiota associated to body surfaces. Understanding the mechanisms that govern this relationship at the molecular, cellular, and ecological levels is central to both health and disease. The present review of rodent models commonly used to investigate microbial-host “conversations” is focused on those complex bacterial communities residing in the lower gut. Although many types of pathology have been studied using gnotobiotic animals, only the models relevant to commensal bacteria will be described.  相似文献   
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