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1.
Previous studies have shown that intradermally (ID) injected Brugia pahangi L3s migrate through various tissues and into the lymphatics of gerbils in a distinct pattern. Excretory/secretory products (ES) produced at the time of invasion of B. pahangi are likely to be important in this early migration phase of the parasite life cycle in their rodent host. Hence, early L3 ES was collected from 24 h in vitro cultures of B. pahangi L3 larvae and used in immunization experiments to investigate the effect of immunity to early L3 ES on worm migration, survival and development of B. pahangi. Immunization of gerbils with ES in RIBI adjuvant produced antibodies to numerous ES proteins eliciting a strong humoral response to ES and indirect fluorescent antibody (IFA) assay using anti-ES serum recognized the ES proteins on the surface of B. pahangi L3 larvae. Following ES immunization, gerbils were challenged either ID or intraperitoneally (IP) with 100 L3s of B. pahangi and euthanized at 3 or 106 days post inoculation (DPI). Immunization with early ES slowed the migration of ID inoculated L3 at 3 DPI and significantly altered the locations of adult worms at 106 DPI. Immunization did not induce protection in any treatment group. However, immunized animals had significantly fewer microfilariae per female worm suggesting the antigens in ES are important in microfilariae development or survival in the host. The number of lymphatic granulomas was also significantly reduced in ES immunized animals. It is important to note that microfilariae serve as a nidus in these granulomas. Our results shows immunization with early Brugia malayi L3 ES alters the worm migration, affects circulating microfilarial numbers and reduces lymphatic granulomas associated with B. pahangi infection in gerbils.  相似文献   
2.
Larger amounts of enterotoxin were produced when Staphylococcus aureus S-6 was grown under still (nonshaken) conditions in a medium that was a paste or gel than were produced in a liquid dispersion with the same colloidal ingredient or in control basal broth (4% NZ Amine-NAK containing 50 mug of thiamine per 100 ml and 1 mg of niacin per 100 ml). Four colloidal ingredients were used which had been previously demonstrated to not support enterotoxin production in buffer. The effect of the type of dispersion occurred earlier than that of the colloidal ingredient, but interactions were found. This effect was not observed when the cells were grown with aeration (shaken). Four other strains of S. aureus followed a similar pattern for enterotoxins A, B, and C, although liquid and paste with cornstarch and carrageenan were the only media compared to the control broth. Enterotoxins A and B were produced earlier by S. aureus S-6, and much greater quantities of enterotoxins were produced for all strains when incubated shaken.  相似文献   
3.
Ohne ZusammenfassungMit 8 TextabbildungenMit Unterstützung der Deutschen Forschungsgemeinschaft.  相似文献   
4.

Background

In September 2013, the United Nations Inter-agency Group for Child Mortality Estimation (UN IGME) published an update of the estimates of the under-five mortality rate (U5MR) and under-five deaths for all countries. Compared to the UN IGME estimates published in 2012, updated data inputs and a new method for estimating the U5MR were used.

Methods

We summarize the new U5MR estimation method, which is a Bayesian B-spline Bias-reduction model, and highlight differences with the previously used method. Differences in UN IGME U5MR estimates as published in 2012 and those published in 2013 are presented and decomposed into differences due to the updated database and differences due to the new estimation method to explain and motivate changes in estimates.

Findings

Compared to the previously used method, the new UN IGME estimation method is based on a different trend fitting method that can track (recent) changes in U5MR more closely. The new method provides U5MR estimates that account for data quality issues. Resulting differences in U5MR point estimates between the UN IGME 2012 and 2013 publications are small for the majority of countries but greater than 10 deaths per 1,000 live births for 33 countries in 2011 and 19 countries in 1990. These differences can be explained by the updated database used, the curve fitting method as well as accounting for data quality issues. Changes in the number of deaths were less than 10% on the global level and for the majority of MDG regions.

Conclusions

The 2013 UN IGME estimates provide the most recent assessment of levels and trends in U5MR based on all available data and an improved estimation method that allows for closer-to-real-time monitoring of changes in the U5MR and takes account of data quality issues.  相似文献   
5.
鲻鱼早期卵子发生的超微结构研究   总被引:13,自引:0,他引:13  
用电子显微镜技术观察鲻鱼早期卵子发生进入第一次成熟分裂前期联会丝复合体期、粗线期、双线期和网状期卵原细胞和初级卵母细胞生发泡和胸质的超微结构特点。在联会丝复合体期,生发泡内同源染色体配对,联会丝复合体中央出现重组节,胞质中不同发育类型的核仁样及其相关线粒体的分布及其数量可作为划分鲻鱼早期卵子发生各个时期的依据。另外,首次观察到靠近膜细胞有一种不规则形细胞,推测是分泌成熟抑制肽细胞。  相似文献   
6.
7.
The Enterobacter cloacae complex is genetically very diverse. The increasing number of complete genomic sequences of E. cloacae is helping to determine the exact relationship among members of the complex. E. cloacae P101 is an endophyte of switchgrass (Panicum virgatum) and is closely related to other E. cloacae strains isolated from plants. The P101 genome consists of a 5,369,929 bp chromosome. The chromosome has 5,164 protein-coding regions, 100 tRNA sequences, and 8 rRNA operons.  相似文献   
8.
Human adenovirus infection is life threatening after allogeneic haematopoietic stem cell transplantation (HSCT). Immunotherapy with donor-derived adenovirus-specific T cells is promising; however, 20% of all donors lack adenovirus-specific T cells. To overcome this, we transfected α/β T cells with mRNA encoding a T-cell receptor (TCR) specific for the HLA-A*0101-restricted peptide LTDLGQNLLY from the adenovirus hexon protein. Furthermore, since allo-reactive endogenous TCR of donor T lymphocytes would induce graft-versus-host disease (GvHD) in a mismatched patient, we transferred the TCR into γ/δ T cells, which are not allo-reactive. TCR-transfected γ/δ T cells secreted low quantities of cytokines after antigen-specific stimulation, which were increased dramatically after co-transfection of CD8α-encoding mRNA. In direct comparison with TCR-transfected α/β T cells, TCR-CD8α-co-transfected γ/δ T cells produced more tumor necrosis factor (TNF), and lysed peptide-loaded target cells as efficiently. Most importantly, TCR-transfected α/β T cells and TCR-CD8α-co-transfected γ/δ T cells efficiently lysed adenovirus-infected target cells. We show here, for the first time, that not only α/β T cells but also γ/δ T cells can be equipped with an adenovirus specificity by TCR-RNA electroporation. Thus, our strategy offers a new means for the immunotherapy of adenovirus infection after allogeneic HSCT.  相似文献   
9.
在我国东北西部半干旱风沙区,春季玉米幼苗经常受到大风和风沙流危害.为了解风沙流危害下玉米幼苗的逆境生理特征,2013年在内蒙古东部科尔沁沙地研究了0(CK)、6、9、12、15和18 m·s-1等6个风速(风沙流强度分别为0、1.00、28.30、63.28、111.82和172.93g·cm-1·min-1)10 min吹袭下幼苗丙二醛含量、膜透性、保护酶活性和渗透调节物质含量的变化.结果表明:6~12 m·s-1的风沙流吹袭对玉米幼苗叶片含水量影响较小,而15和18m·s-1的风沙流吹袭导致其叶片相对含水量分别下降19.0%和18.7%.随着风沙流吹袭强度的增大,其丙二醛含量趋于下降,15和18 m·s-1处理分别较CK下降35.0%和39.0%;而膜透性大幅度增加,15和18 m·s-1处理分别较CK增加191.3%和187.8%;SOD活性降低,CAT反应不敏感,POD活性显著增强.对于风沙流造成的轻度水分胁迫,其可溶性糖和脯氨酸均未发挥渗透调节作用,但在15和18 m·s-1强风沙流吹袭下其脯氨酸含量分别增加11.4%和24.5%,起到了渗透调节作用.  相似文献   
10.
目的:观察天香胶囊对晕动病模型大鼠前庭核NMDAR1(N-甲基-D-天冬氨酸受体1,N-methyl-D-aspartate acid receptor 1)、P-CaMKⅡ (磷酸化钙调蛋白激酶Ⅱ-亚基,the phosphorylation of calmodulin protein kinase Ⅱ alpha subunit)、P-CREB(磷酸化cAMP反应元件结合蛋白,the phosphorylation of cAMP response element binding protein)表达的影响,探讨天香胶囊调节晕动病模型大鼠前庭核兴奋性的内在分子机制。方法:将36只雄性SD大鼠随机分为正常对照组、模型组、阳性药对照组(东莨菪碱)、天香胶囊低、中、高剂量组。灌胃预给药3天后,采用双轴旋转刺激法复制大鼠晕动病模型,通过Western blotting法检测各组大鼠前庭核NMDAR1、P-CaMKⅡ/CaMKⅡ、P-CREB/CREB的表达情况。结果:与正常组大鼠相比,模型组大鼠前庭核NMDAR1、P-CaMKⅡ、P-CREB蛋白表达水平显著增加;与模型组相比,中、高剂量天香胶囊可显著下调晕动病模型大鼠前庭核组织NMDAR1、P-CaMKⅡ、P-CREB蛋白表达。结论:天香胶囊可抑制晕动病模型大鼠前庭核NMDAR1信号通路的活化,这可能是其在治疗晕动病中降低前庭核兴奋性的内在分子机制之一。  相似文献   
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