The human immunodeficiency virus type 1 carboxyl-terminal third of capsid sequence in Gag-Pol is essential but not sufficient for efficient incorporation of Pr160<Superscript><Emphasis Type="Italic">gag-pol</Emphasis></Superscript> into virus particles

To elucidate the role of the C-terminal portion of Gag in the incorporation of human immunodeficiency virus type 1 (HIV-1) Gag-Pol into virus particles, a series of HIV-1 Gag-Pol mutants with deletions in the C-terminalgag sequence was constructed and viral incorporation of the Gag-Pol deletion mutants was analyzed using cotransfecting 293T cells with a Pr55 ^gag expression plasmid. The biological function of the incorporated HIV-1pol gene product was tested using an infectivity assay of the released virus particles which were pseudotyped with the murine leukemia virus Env. Analysis indicated that Gag-Pol deletion mutants, with a removal of the matrix (MA) and/or nucleocapsid (NC) or of the N-terminal two thirds of thegag coding sequence, could be incorporated efficiently into virus particles and produce significant amounts of infectious virions when assayed in a single-cycle infection assay. In contrast, mutations involving a deletion of the major homology region and the adjacent C-terminal capsid sequence significantly affected Gag-Pol incorporation. However, incorporation into virus particles of a Gag-Pol deletion mutant retaining both the major homology region and the adjacent C-terminal capsid intact was still severely impaired. This suggests that the capsid major homology region and the adjacent C-terminal capsid sequence in Gag-Pol are necessary but not sufficient for the incorporation of HIV-1 Pr160 ^gag-pol into virus particles.     

Gender differences in human immunodeficiency virus type 1-specific CD8 responses in the reproductive tract and colon following nasal peptide priming and modified vaccinia virus Ankara boosting

Induction of mucosal anti-human immunodeficiency virus type 1 (HIV-1) T-cell responses in males and females will be important for the development of a successful HIV-1 vaccine. An HIV-1 envelope peptide, DNA plasmid, and recombinant modified vaccinia virus Ankara (rMVA) expressing the H-2D(d)-restricted cytotoxic T lymphocyte P18 epitope were used as immunogens to test for their ability to prime and boost anti-HIV-1 T-cell responses at mucosal and systemic sites in BALB/c mice. We found of all prime-boost combinations tested, an HIV-1 Env peptide subunit mucosal prime followed by systemic (intradermal) boosting with rMVA yielded the maximal induction of gamma interferon (IFN-gamma) spot-forming cells in the female genital tract and colon. However, this mucosal prime-systemic rMVA boost regimen was minimally immunogenic for the induction of genital, colon, or lung anti-HIV-1 T-cell responses in male mice. We determined that a mucosal Env subunit immunization could optimally prime an rMVA boost in female but not male mice, as determined by the magnitude of antigen-specific IFN-gamma responses in the reproductive tracts, colon, and lung. Defective mucosal priming in male mice could not be overcome by multiple mucosal immunizations. However, rMVA priming followed by an rMVA boost was the optimal prime-boost strategy for male mice as determined by the magnitude of antigen-specific IFN-gamma responses in the reproductive tract and lung. Thus, prime-boost immunization strategies able to induce mucosal antigen-specific IFN-gamma responses were identified for male and female mice. Understanding the cellular and molecular basis of gender-determined immune responses will be important for optimizing induction of anti-HIV-1 mucosal immune responses in both males and females.     

Sodium Ion Stabilized Vanadium Oxide Nanowire Cathode for High‐Performance Zinc‐Ion Batteries

Aqueous Zn‐ion batteries (ZIBs) have received incremental attention because of their cost‐effectiveness and the materials abundance. They are a promising choice for large‐scale energy storage applications. However, developing suitable cathode materials for ZIBs remains a great challenge. In this work, pioneering work on the designing and construction of aqueous Zn//Na_0.33V₂O₅ batteries is reported. The Na_0.33V₂O₅ (NVO) electrode delivers a high capacity of 367.1 mA h g^?1 at 0.1 A g^?1, and exhibits long‐term cyclic stability with a capacity retention over 93% for 1000 cycles. The improvement of electrical conductivity, resulting from the intercalation of sodium ions between the [V₄O₁₂]_n layers, is demonstrated by single nanowire device. Furthermore, the reversible intercalation reaction mechanism is confirmed by X‐ray diffraction, Raman, X‐ray photoelectron spectroscopy, scanning electron microscopy, and transmission electron microscopy analysis. The outstanding performance can be attributed to the stable layered structure and high conductivity of NVO. This work also indicates that layered structural materials show great potential as the cathode of ZIBs, and the indigenous ions can act as pillars to stabilize the layered structure, thereby ensuring an enhanced cycling stability.     

卡介苗对枯否细胞生物特性影响的免疫细胞化学研究

卡介苗(BCG)是增强肝枯否细胞(KC)抗肝癌细胞作用的最佳免疫制剂之一。本实验是给大鼠BCG后,应用溶菌酶免疫细胞化学法显示KC,以图象分析系统测定KC的数量、分布和面积,以细胞分光光度计测定KC溶菌酶活性;分离KC体外受BCG作用后,用ELISA法测定RC的Fc受体表达。结果显示:BCG使KC数量增多一倍,尤以肝小叶周边带为显著;KC体积明显增大,细胞面积增大55.71％,周边带KC面积增大一倍上;细胞溶菌酶光密度增大64.35％;Fc受体表达增强64.82％。上述结果是BCG增强KC抗肝癌细胞作用有关细胞学机制。     

Hypoxia affects mitochondrial protein expression in rat skeletal muscle

Hypoxia affects mammalian mitochondrial function, as well as mitochondria-based energy metabolism. The detail mechanism has not been fully understood. In this study, we detected protein expression levels in mitochondrial fractions of Wistar rats exposed to hypobaric hypoxia by use of proteomic methods. Adult male Wistar rats were randomized into an hypoxic (4,500?m, 30 days) group and a normoxic control group (sea level). Gastrocnemius muscles mitochondria were extracted and purified. Mitochondrial oxygen consumption was measured with a Clark oxygen electrode; mitochondrial transmembrane potential was detected with Rhodamine 123 as a fluoresce probe. Using 2-DE and MALDI-TOF MS analysis, we identified eight mitochondrial protein spots that were differentially expressed in the hypoxic group compared with the normoxic control. These proteins included Chain A of F1-ATPase, voltage dependent anion channel 1 (VDAC), hydroxyacyl Coenzyme A dehydrogenase α-subunit, mitochondrial F1 complex γ-subunit, androgen-regulated protein and tripartite motif protein 50. Two of the spots, VDAC and ATP synthase α-subunit, were confirmed by Western blotting analysis. Oxygen consumption during State 3 respiration, as well as the respiratory control ratio (RCR) was significantly higher in the control than that in the hypoxic group; mitochondrial transmembrane potential was significantly higher in hypoxic group than that in the control. With successful use of multiple proteomic analysis techniques, we demonstrates that 30 days hypoxia exposure has effects on the expression of mitochondrial proteins involved in ATP production and lipid metabolism, decrease the stability of mitochondrial membrane, and affect the mitochondrial electron transport chain.     

Association between the TP53 polymorphisms and lung cancer risk: a meta-analysis

The previous published data on the association between TP53 codon 72, intron 6, and intron 3 16 bp polymorphisms and lung cancer risk remained controversial. This meta-analysis of literatures was performed to derive a more precise estimation of the relationship. 38 publications with 51 studies were selected for this meta-analysis, including 17,337 cases and 16,127 controls for TP53 codon 72 (from 43 studies), 2,201 cases and 2,399 controls for TP53 intron 6 (from four studies), and 4,322 cases and 4,558 controls for TP53 intron 3 16 bp (from four studies). When all the eligible studies were pooled into the meta-analysis of codon 72 polymorphism, there was significant association between lung cancer risk and codon 72 polymorphism in any genetic model (dominant model: OR = 1.13, 95 % CI 1.05–1.21; recessive model: OR = 1.14, 95 % CI 1.02–1.27; additive model: OR = 1.19, 95 % CI 1.05–1.33). In the subgroup analysis by ethnicity, histological type, source of control, and smoking status, significantly increased risks were observed in subgroups such as Asians, Caucasians, lung squamous cell carcinoma patients for Asians, population-based study, hospital-based study, non-smokers, and smokers. When all the eligible studies were pooled into the meta-analysis of intron 6 polymorphism, there was significant association between lung cancer risk and intron 6 polymorphism in dominant model (OR = 1.27, 95 % CI 1.11–1.44). When all the eligible studies were pooled into the meta-analysis of intron 3 16 bp polymorphism, there was significant association between lung cancer risk and intron 3 16 bp polymorphism in dominant model (OR = 1.12, 95 % CI 1.02–1.23) and additive model (OR = 1.41, 95 % CI 1.04–1.90). Additionally, when one study was deleted in the sensitive analysis, the results of TP53 intron 3 16 bp duplication polymorphism were changed in the dominant model (OR = 1.11, 95 % CI 0.87–1.42) and additive model (OR = 1.01, 95 % CI 0.65–1.56). In summary, this meta-analysis indicates that codon 72 and intron 6 polymorphisms show an increased lung cancer risk. A study with the larger sample size is needed to further evaluated gene-environment interaction on TP53 codon 72, intron 6, and intron 3 16 bp polymorphisms and lung cancer risk.     

Meta-analysis of the association between common interleukin-1 polymorphisms and dental implant failure

Interleukin-1 (IL) plays a pivotal role in immune–inflammatory response that maintains periodontal homeostasis. A number of epidemiological studies have been conducted to investigate the associations between common polymorphisms of IL-1 (IL-1A, IL-1B) genes and risk of peri-implant disease, but the findings remain inconclusive. Thirteen studies evaluating the association between IL-1 polymorphisms and risk for peri-implant diseases (implant failure/loss, peri-implantitis) were included. Fixed model or random-effects models were applied to calculate overall and ethnicity-specific summary odds ratios (ORs) and corresponding 95 % confidence intervals (CIs) as risk estimates for IL-1 polymorphisms individually or in combination. Heterogeneity and publication bias were evaluated by Q-test, I ² statistic, Begg’s funnel plot and Egger’s test accordingly. The composite genotype of IL-1A (?889) and IL-1B (+3954) was associated with increased risk of implant failure/loss (OR 1.76, 95 % CI 1.21–2.57) and peri-implantitis (OR 2.34, 95 % CI 1.03–5.33). The significance was borderline in European descents (implant failure/loss: OR 1.48, 95 % CI 0.99–2.22; peri-implantitis: OR 1.65, 95 % CI 1.00–2.73). T allele of IL-1B (?511) was associated with increased risk of implant failure/loss (OR 1.28, 95 % CI 1.01–1.62), while the association was not significant in European descents (OR 1.12, 95 % CI 0.85–1.48). These findings support a potential role of IL-1 polymorphisms, particularly the composite genotype of IL-1A (?889) and IL-1B (+3954), in peri-implant disease susceptibility. More studies with large sample size are needed to validate the associations.     

Effects of long-term serial cell passaging on cell spreading,migration, and cell-surface ultrastructures of cultured vascular endothelial cells

The effects of serial cell passaging on cell spreading, migration, and cell-surface ultrastructures have been less investigated directly. This study evaluated the effects of long-term serial cell passaging (totally 35 passages) on cultured human umbilical vein endothelial cells which were pre-stored at −80 °C as usual. Percentage- and spread area-based spreading assays, measurements of fluorescently labeled actin filaments, migration assay, and measurements of cell-surface roughness were performed and quantitatively analyzed by confocal microscopy or atomic force microscopy. We found that the abilities of cell spreading and migration first increased at early passages and then decreased after passage 15, in agreement with the changes in average length of actin filaments. Recovery from cold storage and effects of cell passaging were potentially responsible for the increases and decreases of the values, respectively. In contrast, the average roughness of cell surfaces (particularly the nucleus-surrounding region) first dropped at early passages and then rose after passage 15, which might be caused by cold storage- and cell passaging-induced endothelial microparticles. Our data will provide important information for understanding serial cell passaging and implies that for pre-stored adherent cells at −80 °C cell passages 5–10 are optimal for in vitro studies.     

受白粉菌诱导大麦抗感等基因系蛋白质变化的双向电泳分析

分别对接种与否的大麦抗—感白粉病等基因系—叶期幼苗取材进行蛋白质双向电泳分析。结果表明,病原的侵入使抗—感两系在30Kd以下的低分子量区域的蛋白质发生了明显变化。接种48小时之后,抗病系在pH5.5、6.0、6.8及8.8附近出现了对照中所没有的蛋白质,而在pH6.0和8.8附近的蛋白质则较对照有减小的趋势;感病系在pH6.0附近蛋白质明显增多,在pH8.8处不仅在量上有大幅度提高,而且种类也有增加。结果还表明,抗—感系间在未接种的情况下双向电泳图谱也有差异,接种之后由于感病系在pH8.8处蛋白质的特异性合成,使抗—感两系间的差异缩小。     

Variation in the significant environmental factors affecting larval abundance of four major Chinese carp species: fish spawning response to the Three Gorges Dam

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