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971.
Effects of platelet activating factor on capacitation and acrosome reaction in mouse spermatozoa 总被引:10,自引:0,他引:10
Platelet activating factor (PAF) plays an important role in mammalian reproduction. The aim of this study was to investigate the effects of PAF on capacitation and acrosome reaction of mouse spermatozoa by chlortetracycline (CTC) fluorescence assay and coomassie blue staining. The percentage of capacitated mouse spermatozoa was increased (P < 0.05) by incubation with 50 ng/ml PAF for 20-120 min. The peak response occurred between 80 to 100 min of exposure to PAF. In contrast, the effects of PAF on acrosome reaction may be not receptor-mediated since lyso-PAF had the same effects. Ionophore A23187 stimulated an increase in acrosome-reacted spermatozoa of PAF-treated spermatozoa, but not of lyso-PAF-treated ones. These results suggest that PAF mainly acts on sperm capacitation. 相似文献
972.
Soromou LW Chen N Jiang L Huo M Wei M Chu X Millimouno FM Feng H Sidime Y Deng X 《Biochemical and biophysical research communications》2012,419(2):256-261
Astragalin (AG), a flavonoid from many traditional herbs and medicinal plants, has been described to exhibit in vitro anti-inflammatory activity. The present study aimed to determine the protective effects and the underlying mechanisms of astragalin on lipopolysaccharide-induced endotoxemia and lung injury in mice. Mice were injected intraperitoneally (i.p.) with lipopolysaccharide (LPS) (dose range: 5-40 mg/kg). We observed mice on mortality for 7 days twice a day and recorded survival rates. In drug testing, we examined the therapeutic effects of astragalin (25, 50 or 75 mg/kg) on LPS- induced endotoxemia by dosing orally astragalin 1 hour before LPS challenge. Using an experimental model of LPS-induced acute lung injury (ALI), we examined the effect of astragalin in resolving lung injury. The investigations revealed that pretreatment with astragalin can improve survival during lethal endotoxemia and attenuate inflammatory responses in a murine model of lipopolysaccharide-induced acute lung injury. The mechanisms by which Astragalin exerts its anti-inflammatory effect are correlated with inhibition of tumor necrosis factor-α (TNF-α), interleukin-1 (IL-1), and interleukin-6 (IL-6) production via inactivation of NF-κB. 相似文献
973.
Bao-Gui Jiang Yuan-Chun Zheng Yi-Gang Tong Na Jia Qiu-Bo Huo Hang Fan Xue-Bing Ni Lan Ma X. Frank Yang Jia-Fu Jiang Wu-Chun Cao 《Journal of bacteriology》2012,194(24):7014-7015
We report here the genome sequence of Borrelia afzelii strain HLJ01, isolated from a patient with Lyme disease in China. It is the first report of the whole genome of a B. burgdorferi sensu lato isolate from a human in China. 相似文献
974.
Lambda-1 interferon (IFN-λ1) and cyclooxygenase-2 (COX-2) were reported to play an important role in host antiviral defense. However, the mechanism by which IFN-λ1 and COX2 are activated and modulated during viral infection remains unclear. In this study, we found that expression of both circulating IFN-λ1 and COX2-derived prostaglandin E2 (PGE2) was coordinately elevated in a cohort of influenza patients compared to healthy individuals. Expression of IFN-λ1 was blocked by a selective COX2 inhibitor during influenza A virus infection in A549 human lung epithelial cells but enhanced by overexpression of COX2, indicating that the production of IFN-λ1 is COX2 dependent. COX2 was able to increase IFN-λ1 expression by promoting NF-κB binding to the enhancer in the IFN-λ1 promoter. We found that epigenetic changes activate COX2 expression and PGE2 accumulation during viral infection. The expression of DNA methyltransferase 3a (DNMT3a) and DNMT3b, but not that of DNMT1, was downregulated following influenza A virus infection in both A549 cells and peripheral blood mononuclear cells (PBMCs). We showed that microRNA miR29 suppresses DNMT activity and thus induces expression of COX2 and PGE2. Furthermore, miR29 expression was elevated 50-fold in virally infected A549 cells and 10-fold in PBMCs from influenza patients, compared to expression after mock infection of A549 cells or in healthy individuals, respectively. Activation of the protein kinase A signaling pathway and phosphorylation of CREB1 also contributed to COX2 expression. Collectively, our work defines a novel proinflammatory cascade in the control of influenza A virus infection. 相似文献
975.
龙云杨泽娟黄小庆郭宇明严文兵招活 《现代生物医学进展》2012,12(24):4651-4653
目的:观察稳恒强磁外贴治疗附睾慢性炎症性结节、囊肿的效果,寻找非药物治疗附睾慢性炎症性结节、囊肿的方法.方法:园形强磁铁2块(直径2cm厚0.5cm,2块叠加厚度达1厘米)分别在内裤内外各一块作为固定,内裤向上提使磁块贴附附睾慢性炎症性结节、囊肿位置.在不影响工作生活的情况下持续粘贴,不能持续者则改用每天晚上睡觉时粘贴.结果:280例经彩超检测为附睾炎症性肿大结节、囊肿病人,持续外贴治疗24小时至72小时后,280例病人会阴及下腹部不适、痛疼症状均明显缓解;持续外贴治疗1周症状消失的有145例,症状基本消失的有35例;持续2-3周则症状全部消失.附睾增大变硬者经2周治疗局部触诊变软缩小,彩超提示结节变小.217例结节、囊肿患者中持续3至4周治疗肿物消失,彩超报告提示为正常附睾声像的有150例,67例大小较前明显变小,有效率达100%.结论:稳恒强磁外贴治疗附睾炎症性肿大结节、囊肿完全有效,是一种安全有效简便、无痛苦、易操作、价廉的值得推广的非药物治疗方法. 相似文献
976.
目的:本研究通过建立糖尿病大鼠动物模型,观察海藻溴酚化合物A、B对糖尿病大鼠机体抗氧化水平的影响。方法:采用STZ注射法制作糖尿病(DM)大鼠模型,随机分为空白对照组、糖尿病模型组、化合物A低剂量组及高剂量组、化合物B低剂量组及高剂量组,灌胃给药12周。12周末处死大鼠,测肾匀浆中谷胱甘肽过氧物酶(GSH-Px)的活力及丙二醛(MDA)的含量;并采用透射电镜观察大鼠肾组织的病理改变。结果:与空白对照组相比,糖尿病模型组肾组织匀浆中GSH-Px活力下降,MDA含量升高,差异有统计学意义(P<0.05)。各干预组中GSH-Px的活力较糖尿病模型组有升高的趋势,MDA含量有下降趋势。电镜下各干预组肾小球及肾小管病变较糖尿病组减轻,且高剂量组优于低剂量组。结论:溴酚化合物A、B能提高糖尿病大鼠机体抗氧化水平,并能一定程度的改善肾脏病理改化,但其具体机制有待进一步探讨。 相似文献
977.
p75NTR is a low-affinity nerve growth factor receptor, which promotes cell proliferation as a positive modulator of high-affinity
receptor TrkA, as well as binds with cell ligands to induce apoptosis and mediate death signals. To analyze the regulatory
mechanisms of p75NTR, the present study utilized a new membrane yeast two-hybrid system to screen a human fetal brain cDNA
library. Results identified BFAR, a novel protein that interacts with p75NTR. Interaction specificity was verified by membrane
yeast two-hybrid co-transformation assays, in vitro GST pull-down assays, and in vitro co-immunoprecipitation assays. The fluorescent subcellular localization assay revealed that the two proteins co-localized
within the cytoplasm. BFAR overexpression in PC-12 and HEK293T cells inhibited the NFκB and JNK signaling pathway, as determined
with the luciferase test. Co-transfected p75NTR and BFAR in HEK293T or PC-12 cells, respectively, increased the percentage
of cells in the G2/M phase, decreased the number of S-phase cells, and did not change the number of G0/G1-phase cells. 相似文献
978.
979.
Fengzhi You Kaiming Huo Ruili Wang Dongmei Xu Jie Deng Ying Wei Fenglian Shi Hongyang Liu Guomei Cheng Zhan Zhang Ping Yang Tao Sun Xiaoyang Wang Bo Jacobsson Changlian Zhu 《PloS one》2012,7(10)
Background
Maternal deaths occur mostly in developing countries and the majority of them are preventable. This study analyzes changes in maternal mortality and related causes in Henan Province, China, between 1996 and 2009, in an attempt to provide a reliable basis for introducing effective interventions to reduce the maternal mortality ratio (MMR), part of the fifth Millennium Development Goal.Methods and Findings
This population-based maternal mortality survey in Henan Province was carried out from 1996 to 2009. Basic information was obtained from the health care network for women and children and the vital statistics system, from specially trained monitoring personnel in 25 selected monitoring sites and by household survey in each case of maternal death. This data was subsequently reported to the Henan Provincial Maternal and Child Healthcare Hospital. The total MMR in Henan Province declined by 78.4%, from 80.1 per 100 000 live births in 1996 to 17.3 per 100 000 live births in 2009. The decline was more pronounced in rural than in urban areas. The most common causes of maternal death during this period were obstetric hemorrhage (43.8%), pregnancy-induced hypertension (15.8%), amniotic fluid embolism (13.9%) and heart disease (8.0%). The MMR was higher in rural areas with lower income, less education and poorer health care.Conclusion
There was a remarkable decrease in the MMR in Henan Province between 1996 and 2009 mainly in the rural areas and MMR due to direct obstetric causes such as obstetric hemorrhage. This study indicates that improving the health care network for women, training of obstetric staff at basic-level units, promoting maternal education, and increasing household income are important interventional strategies to reduce the MMR further. 相似文献980.
Guan X Yabuuchi A Huo H Ginsberg E Racowsky C Daley GQ Lerou PH 《Stem cell research》2012,8(3):410-415
Deficiency of the nuclear factor-kappa-B essential modulator (NEMO) is a rare X-linked disorder that presents in boys as hypohydrotic ectodermal dysplasia with immunodeficiency due to defective nuclear factor-κB activation. Here we report on the generation of 2 human embryonic stem cell lines from discarded in vitro fertilization (IVF) embryos ascertained via preimplantation genetic diagnosis. We have derived two human embryonic stem cell lines that carry a T458G hypomorphic mutation in exon 4 of the NEMO (or IKBKG) gene. One of the lines is diploid male; the other is diploid female but has clonally inactivated the X-chromosome that harbors the wild-type IKBKG gene. We show that both lines are pluripotent, have the capacity to differentiate into hematopoietic progenitors, and have defective inhibitor of nuclear factor kappa-B kinase activity. These NEMO deficiency hES cell lines provide an unlimited source for differentiated cell types and may serve as a unique tool to study NEMO deficiency and potentially lead to the development of new therapies for this disease. 相似文献