Baseline antibody level may help predict the risk of active human cytomegalovirus infection in a HCMV seropositive population

European Journal of Clinical Microbiology & Infectious Diseases - Recurrent human cytomegalovirus (HCMV) infection during pregnancy could lead to congenital HCMV infection and permanent...     

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??OBJECTIVE To investigate the chemical constituents in chloroform extraction of Tetrastigmatis hemsleyani diels et. Gilg and their antitumor activities. METHODS Various chromatography techniques such as column chromatography on silica gel, Sephadex LH-20 and preparative TLC were used to isolate and purify the compounds. Their structures were identified by¹H-NMR,¹³C-NMR and MS. Their antitumor activities was tested by MTT method. Moreover, the other compounds of chloroform extraction were detected by GC-MS. RESULTS Six compounds were isolated by classic chromatography and identified as ??-sitosterol(1), 4-hydroxy-3-methoxybenzaldehyde(2), oleanolic acid (3), 5-hydroxymethyl furfural(4), azelaic acid(5), vanillic acid(6). Twenty-two compounds were identified by GC-MS. CONCLUSION Compounds 2-6 are isolated from this plant for the first time. Compounds 1 and 3 shows strong cytotoxic activities against Hela229 with IC₅₀ values of 40.78, 25.69 ??g??mL^-1, respectively. Compound 3 also showed strong cytotoxic activities against with IC₅₀ values of 69.87 ??g??mL^-1. The result proved that antitumor activity of chloroform extraction of Tetrastigmatis hemsleyani diels et. Gilg is due to the contribution of multi-components.
     

Novel bi-allelic variants in DNAH2 cause severe asthenoteratozoospermia with multiple morphological abnormalities of the flagella

Research questionMultiple morphological abnormalities of the flagella (MMAF) is characterized by excessive immotile spermatozoa with severe flagellar abnormalities in the ejaculate. Previous studies have reported a heterogeneous genetic profile associated with MMAF. What other genetic variants might explain the cause of MMAF?DesignWhole-exome sequencing was conducted in a cohort of 90 Chinese patients with MMAF. The pathogenicity of identified mutations was assessed through electron microscopy and immunofluorescent examinations.ResultsThree unrelated men with bi-allelic DNAH2 variants were identified. Sanger sequencing verified that the six novel variants originated from every parent. All these variants were located at the conserved domains of DNAH2 and predicted to be deleterious by bioinformatic tools. Haematoxylin and eosin staining and scanning electron microscopy revealed that spermatozoa harbouring DNAH2 variants displayed severely aberrant morphology mainly with absent and short flagella (≥78%). Moreover, transmission electron microscopy revealed the obvious absence of a central pair of microtubules and inner dynein arms in the spermatozoa with mutated DNAH2. Immunofluorescence data further validated these findings, showing reduced DNAH2 protein expression in the spermatozoa with DNAH2 variants, compared with normal spermatozoa. Intracytoplasmic sperm injection using spermatozoa from the three men with mutated DNAH2 resulted in blastocyst formation in all cases. Embryo transfer was carried out in two couples, both resulting in clinical pregnancy.ConclusionsThese experimental and clinical data suggest that bi-allelic DNAH2 variants might induce MMAF-associated asthenoteratozoospermia, which can be overcome through intracytoplasmic sperm injection. These findings contribute to the knowledge of the genetic landscape of asthenoteratozoospermia and clinical counselling of male infertility.     

大学生QQ依赖问卷的初步编制

目的 编制适合测查大学生QQ依赖程度的测评工具,为研究大学生网络人际交往提供科学依据.方法 结合文献回顾、半结构式访谈、专家咨询等方法编制问卷,对厦门地区某所综合性高校的700名大学生进行问卷调查,检验问卷的信、效度.结果 问卷由情感依赖、回应期盼、脱离现实人际、联络代替、过度使用5个因子构成,共计29个项目.问卷总体及各因子的重测信度在0.574 ～0.882之间,内部一致性系数在0.715 ～0.934之间.验证性因素分析结果显示,问卷的RMSEA小于0.08,CFI,RFE,IFI,NFI,NNFI都在0.78以上.结论 大学生QQ依赖问卷具有较高的信、效度,可作为普通综合性院校测查大学生QQ依赖程度的测评工具.     

Imaging Integrin αvβ3 and NRP-1 Positive Gliomas with a Novel Fluorine-18 Labeled RGD-ATWLPPR Heterodimeric Peptide Probe

Purpose

Radiolabeled Arg-Gly-Asp (RGD) and Ala-Thr-Trp-Leu-Pro-Pro-Arg (ATWLPPR) peptide analogs have received interests for their capability to serve as radiopharmaceuticals for imaging integrin α_vβ₃ and Neuropilin-1 (NRP-1) positive tumors, respectively. In this study, we developed a RGD-ATWLPPR heterodimeric peptide which contained both RGD and ATWLPPR motifs in one molecular probe. The aim of this study was to investigate the dual receptor-targeting property and tumor diagnostic value of RGD-ATWLPPR heterodimeric peptide labeled with fluorine-18 (F-18).

Procedures

A RGD-ATWLPPR heterodimer was synthesized from c(RGDyK) and ATWLPPR through a glutamate linker. The peptide was radiolabeled by reacting the [¹⁸F]fluoride–aluminum complex with the cyclic chelator, 1,4,7-triazacyclononane-1,4,7-triacetic acid (NOTA). The receptor-binding characteristics and tumor-targeting efficacy of [¹⁸F]FAl-NOTA-RGD-ATWLPPR were tested in vitro and in vivo.

Results

RGD-ATWLPPR had affinity for both integrin α_vβ₃ and NRP-1 in vitro. [¹⁸F]FAl-NOTA-RGD-ATWLPPR displayed significantly higher tumor uptake than [¹⁸F]FAl-NOTA-RGD and [¹⁸F]FAl-NOTA-ATWLPPR, both in vitro and in vivo. The uptake of the F-18 labeled heterodimer by an U87MG tumor was inhibited only partially in the presence of an excess amount of unlabeled RGD or ATWLPPR but was blocked completely in the presence of both RGD and ATWLPPR. Compared with the monomeric RGD and ATWLPPR peptides, [¹⁸F]FAl-NOTA-RGD-ATWLPPR showed improved in vivo pharmacokinetics, resulting in a more preferable imaging quality.

Conclusions

[¹⁸F]FAl-NOTA-RGD-ATWLPPR exhibited significantly improved receptor-targeting properties both in vitro and in vivo compared with the F-18 labeled RGD or ATWLPPR monomers. The improved targeting and localization exhibited by the RGD-ATWLPPR heterodimer provide a foundation for further investigations of its applicability in clinical tumor imaging.     

自噬参与促进AFB1致肝细胞DNA损伤的修复进程

目的探讨黄曲霉毒素B1(AFB1)肝毒性修复进程中细胞自噬的作用。方法以经50μmol/L AFB1预处理24 h的永生化人正常肝L02细胞建立模型,检测AFB1处理撤除不同时间点的细胞DNA双链损伤指标γH2AX蛋白和自噬标志物LC3-Ⅱ蛋白的表达水平;采用免疫荧光法检测AFB1撤除后细胞中γH2AX蛋白荧光焦点和自噬体形成情况;在AFB1撤除后联合应用自噬抑制剂3-MA进行干预实验,检测细胞内γH2AX蛋白的表达水平。结果L02细胞中γH2AX蛋白的动态表达在AFB1处理撤除12 h后达到最高,并在24 h后逐渐降低;自噬蛋白LC3-Ⅱ和自噬体的形成在AFB1处理撤除后逐渐增强;3-MA可明显减缓AFB1撤处理后细胞内γH2AX蛋白的降低进程。结论细胞自噬参与了AFB1诱导肝细胞毒性损伤的修复进程,与促进DNA损伤的修复有关。