Seroprevalence of pandemic (H1N1) 2009 in pregnant women in China: an observational study

Background

We investigated the seropositive rates and persistence of antibody against pandemic (H1N1) 2009 virus (pH1N1) in pregnant women and voluntary blood donors after the second wave of the pandemic in Nanjing, China.

Methodology/Principal Findings

Serum samples of unvaccinated pregnant women (n = 720) and voluntary blood donors (n = 320) were collected after the second wave of 2009 pandemic in Nanjing. All samples were tested against pH1N1 strain (A/California/7/2009) with hemagglutination inhibition assay. A significant decline in seropositive rates, from above 50% to about 20%, was observed in pregnant women and voluntary blood donors fifteen weeks after the second wave of the pandemic. A quarter of the samples were tested against a seasonal H1N1 strain (A/Brisbane/59/2007). The antibody titers against pH1N1 strain were found to correlate positively with those against seasonal H1N1 strain. The correlation was modest but statistically significant.

Conclusions and Significance

The high seropositive rates in both pregnant women and voluntary blood donors suggested that the pH1N1 virus had widely spread in these two populations. Immunity derived from natural infection seemed not to be persistent well.     

同尾酶技术在构建疟疾多价重组DNA疫苗中的应用

同尾酶是一类识别不同核苷酸序列但能酶切产生相同粘性末端的限制性内切酶,依靠同尾酶的这种特性,可以根据需要将不同的ＤＮＡ 片段进行灵活组合,获得各种排列顺序的多价表位重组疫苗．将这种方法用于疟疾多价重组ＤＮＡ 疫苗的研制;ＢＡＬＢ／ｃ 小鼠免疫实验对所得重组疫苗ＰＵ２８６的免疫原性进行了测定．     

Specific cancer stem cell-therapy by albumin nanoparticles functionalized with CD44-mediated targeting

Background

Cancer stem cells (CSCs) are highly proliferative and tumorigenic, which contributes to chemotherapy resistance and tumor occurrence. CSCs specific therapy may achieve excellent therapeutic effects, especially to the drug-resistant tumors.

Results

In this study, we developed a kind of targeting nanoparticle system based on cationic albumin functionalized with hyaluronic acid (HA) to target the CD44 overexpressed CSCs. All-trans-retinoic acid (ATRA) was encapsulated in the nanoparticles with ultrahigh encapsulation efficiency (EE%) of 93% and loading content of 8.37%. TEM analysis showed the nanoparticles were spherical, uniform-sized and surrounded by a coating layer consists of HA. Four weeks of continuously measurements of size, PDI and EE% revealed the high stability of nanoparticles. Thanks to HA conjugation on the surface, the resultant nanoparticles (HA-eNPs) demonstrated high affinity and specific binding to CD44-enriched B16F10 cells. In vivo imaging revealed that HA-eNPs can targeted accumulate in tumor-bearing lung of mouse. The cytotoxicity tests illustrated that ATRA-laden HA-eNPs possessed better killing ability to B16F10 cells than free drug or normal nanoparticles in the same dose, indicating its good targeting property. Moreover, HA-eNPs/ATRA treatment decreased side population of B16F10 cells significantly in vitro. Finally, tumor growth was significantly inhibited by HA-eNPs/ATRA in lung metastasis tumor mice.

Conclusions

These results demonstrate that the HA functionalized albumin nanoparticles is an efficient system for targeted delivery of antitumor drugs to eliminate the CSCs.

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核桃-小麦复合系统中细根生长动态及竞争策略

以核桃(Juglans regia)-小麦(Triticum aestivum)间作复合系统为研究对象,用微根窗和根钻相结合的方法采样,研究复合系统中核桃和小麦细根年内年际的生长动态和竞争适应策略,为农林复合系统的经营管理和竞争模型的建立提供理论依据和技术支持。结果表明,间作核桃和小麦根系均在上半年有一个大的生长高峰(5月和4月),在下半年有一个小的生长高峰(9月和11月),二者的竞争主要发生在上半年的大生长高峰期。在各年份各土层,间作核桃的根长密度均低于单作核桃,且在从第7年开始存在显著差异。在0—20 cm土层间作小麦根长密度在第3—7年间获得迅速提高,从第7年开始显著高于单作小麦,但在20 cm以下土层则相反。间作使核桃和小麦细根生态位实现了分离,11年的观察期内间作核桃比单作核桃细根的垂直分布中心下移了6.59 cm,间作小麦比单作小麦的上移了8.59 cm。在根系竞争策略方面,小麦根系是通过短期内的快速生长,迅速占据土壤空间获得竞争优势;而核桃根系是通过根系的逐年积累,逐步占据土壤空间从而获得竞争优势。可以干扰核桃根系积累过程的"竞争-干扰-再平衡"农林复合经营管理策略可以让复合系统中核桃和小麦保持各自竞争优势的情况下实现共存。在根系形态方面,自身细根直径较小者小麦在剧烈竞争区域以增加细根直径减小比根长来适应竞争,而自身细根直径较大者核桃则相反。     

APC Inhibits Ligand-Independent Wnt Signaling by the Clathrin Endocytic Pathway

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Alisol A attenuates high‐fat‐diet‐induced obesity and metabolic disorders via the AMPK/ACC/SREBP‐1c pathway

Obesity and its associated metabolic disorders such as diabetes, hepatic steatosis and chronic heart diseases are affecting billions of individuals. However there is no satisfactory drug to treat such diseases. In this study, we found that alisol A, a major active triterpene isolated from the Chinese traditional medicine Rhizoma Alismatis, could significantly attenuate high‐fat‐diet‐induced obesity. Our biochemical detection demonstrated that alisol A remarkably decreased lipid levels, alleviated glucose metabolism disorders and insulin resistance in high‐fat‐diet‐induced obese mice. We also found that alisol A reduced hepatic steatosis and improved liver function in the obese mice model.In addition, protein expression investigation revealed that alisol A had an active effect on AMPK/ACC/SREBP‐1c pathway. As suggested by the molecular docking study, such bioactivity of alisol A may result from its selective binding to the catalytic region of AMPK.Therefore, we believe that Alisol A could serve as a promising agent for treatment of obesity and its related metabolic diseases.     

表达EB病毒主要膜蛋白gp350／220的非复制型重组痘苗病毒的构建

利用非复制痘苗病毒质粒载体pNEOCK11β75及pNEOCK,改造了表达EB病毒主要膜蛋白gp350/22的复制型重组痘苗病毒VMA,构建了非复制型重组痘苗病毒VMA△CK。该病毒能在鸡胚原代成纤维细胞（CEF）中正常繁殖,而在人源细胞中不能正常繁殖。在CEF中连续传代至第25代,经PCR证明,该病毒符合非复制型重组痘苗病毒的特征。经免疫荧光及免疫酶斑法证实,VMA△CK可稳定表达gp350/220,且表达水平与VAM无明显差异。VMA△CK经腹腔免疫Balb/C小鼠,4周后能诱生一定水平的抗gp350/220特异性抗体,加强免疫2周后该抗体水平明显升高。这一结果类似于VMA免疫Balb/C小鼠的结果,初免后,VMA△CK且抗痘苗抗体水平明显低于VMA免疫组;加强免疫2周后,两组小鼠的抗痘苗抗体水平趋于一致。上述结果证明,所构建的非复制痘苗病毒不影响目的抗原的表达,也不影响该抗原的免疫原性,但导致病毒毒力下降,而且用该病毒免疫小鼠后小鼠抗痘苗病毒载体的免疫反应明显下降。     

探讨模拟冷空气降温过程对健康大鼠和高血压大鼠凝血功能的影响

目的:通过模拟冷空气温度变化过程给予健康大鼠和高血压大鼠冷刺激,以此探讨冷空气过程对机体凝血功能的影响。方法:收集张掖市2011年3月一次典型冷空气过程数据,利用气象环境模拟箱模拟其温度变化过程。将24只雄性健康大鼠和24只雄性高血压大鼠分别随机分成最低温组(Tmin组)、Tmin对照组、复温组(Tr组)和Tr对照组。将Tmin组和Tr组大鼠放入气候箱中暴露冷空气温度变化过程。在Tmin和Tr时点分别停止Tmin组大鼠和Tr组大鼠冷空气暴露,并采血以测定其凝血功能指标—凝血四项。结果:与对照组相比,健康大鼠和高血压大鼠活化部分凝血酶原时间(APTT)、凝血酶原时间(PT)、凝血酶时间(TT)在降温后与对照组相比没有显著差异(P>0.05),但血浆纤维蛋白原(Fbg)含量在高血压大鼠和健康大鼠Tmin组明显高于其对照组(P<0.01)。温度恢复后,其在健康组含量仍然高于其对照组(P<0.05),而在高血压大鼠中没有差异(P>0.05)。同Fbg,反应Fbg的纤维蛋白原时间(Fbg-time)在健康大鼠Tmin和Tr组中短于对照组(P<0.01,),而在高血压大鼠中仅在Tmin组短于对照组(P<0.01)。高血压大鼠血中的Fbg含量和Fbgt明显高于和短于健康大鼠(P<0.01)。结论:①冷空气降温过程能增加机体血中Fbg含量,使凝血功能增强,可能增加心血管疾病危险性;②冷空气刺激对健康大鼠凝血功能影响强于高血压大鼠。