CCR5-Δ32 polymorphism—a possible protective factor from gait impairment amongst post-stroke patients

Background and purpose

Stroke and small vessel disease cause gait disturbances and falls. The naturally occurring loss-of-function mutation in the C-C chemokine receptor 5 gene (CCR5-Δ32) has recently been reported as a protective factor in post-stroke motor and cognitive recovery. We sought to examine whether it also influences gait and balance measures up to 2 years after stroke.

Method

Participants were 575 survivors of first-ever, mild–moderate ischaemic stroke or transient ischaemic attack from the TABASCO prospective study, who underwent a 3 T magnetic resonance imaging at baseline and were examined by a multi-professional team 6, 12 and 24 months after the event, using neurological, neuropsychological and mobility examinations. Gait rhythm and the timing of the gait cycle were measured by force-sensitive insoles. CCR5-Δ32 status and gait measures were available for 335 patients.

Results

CCR5-Δ32 carriers (16.4%) had higher gait speed and decreased (better) stride and swing time variability 6 and 12 months after the index event compared to non-carriers (p < 0.01 for all). The association remained significant after adjustment for age, gender, education, ethnicity and stroke severity.

Conclusions

Significant associations were found between gait measurements and CCR5-Δ32 loss-of-function mutation amongst stroke survivors. This is the first study showing that genetic predisposition may predict long-term gait function after ischaemic stroke.     

Peroxisome proliferator-activated receptor-gamma and growth inhibition by its ligands in prostate cancer

Background: Peroxisome proliferator-activated receptor-γ (PPAR-γ) is expressed in certain human cancers. Ligand-induced PPAR-γ activation can result in growth inhibition and differentiation in these cancer cells; however, the precise mechanism for the anti-proliferative effect of PPAR-γ ligands is not clear. Methods: In this study, we examined the expression of PPAR-γ in human prostate cancer and the effect of two PPAR-γ ligands, 15 deoxy-Δ^12,14-prostaglandin J2 (15d-PGJ2) and troglitazone, on prostate cancer cell growth. Results: PPAR-γ is frequently over-expressed in androgen independent prostate cancer cell lines and human prostate cancer tissues (22 of 47; 47%). Both 15d-PGJ2 and troglitazone inhibited proliferation and DNA synthesis of prostate cancer cell lines in a dose-dependent manner, and slightly increased the proportion of cells with S-phase DNA content. Prostate specific antigen (PSA) promoter reporter assays showed that troglitazone and 15d-PGJ2 down-regulated androgen stimulated reporter gene activity in prostate cancer cell lines LNCaP. Interestingly, LNCaP with troglitazone dramatically suppressed PSA protein expression without suppressing AR expression. Conclusions: Taken together, these results suggest that PPAR-γ ligands may be a useful therapeutic agent for the treatment of prostate cancer.     

高表达ΔNp73基因对大肠癌细胞生物学行为的影响及其机制研究

目的 通过增强肿瘤细胞中外源性ΔNp73基因的表达, 探讨该基因对大肠癌细胞生物学行为的影响。方法 以人类大肠癌细胞株LOVO细胞为研究对象,将ΔNp73基因用脂质体法转染LOVO细胞,进行细胞生长曲线和流式细胞术分析,测定转染ΔNp73基因后的LOVO细胞的增殖能力与凋亡率;以Boyden 小室体外侵袭实验检测ΔNp73基因转染前后LOVO细胞侵袭力变化,并用Western blot法检测VEGF蛋白的表达。结果 转染了ΔNp73基因后的LOVO细胞生长速度较未转染ΔNp73的LOVO细胞明显加快(P<0.01),凋亡率降低;Boyden 小室体外侵袭实验显示LOVO ΔNp73细胞穿膜数较空白对照组和LOVO pcDNA3组增多, 差异具有统计学意义(P<0.01)。与空白对照组相比, LOVO ΔNp73细胞中VEGF表达较未转染ΔNp73基因的细胞明显增高(P<0.01)。结论 ΔNp73过表达促进了大肠癌细胞的增殖和血管生成,增强了大肠癌的侵袭力。     

DNA damage and endoplasmic reticulum stress mediated curcumin-induced cell cycle arrest and apoptosis in human lung carcinoma A-549 cells through the activation caspases cascade- and mitochondrial-dependent pathway

Curcumin, a major component of the Curcuma species, is known to have antioxidant, anti-inflammatory properties and induce apoptosis of cancer cells, however, the precise molecular mechanisms of apoptosis in vitro are unclear. In this study, we showed that curcumin, a plant product containing the phenolic phytochemical, caused DNA damage and endoplasmic reticulum (ER) stress and mitochondrial-dependent-induced apoptosis through the activation of caspase-3 at a treatment concentration of 30 microM in human lung cancer A-549 cells. In contrast, treatment with 5-10 microM of curcumin did not induce significant apoptosis, but rather induced G2/M-phase arrest in A-549 cells. Flow cytometric analysis indicated that curcumin directly increased intracellular oxidative stress based on the cell permeable dye, 2',7'-dichlorodihydrofluorescein diacetate (DCFH-DA) acting as an indicator of reactive oxygen species (ROS) generation. GADD153 and GRP78 were increased by curcumin which was indicative of ER stress. Curcumin increased Ca(2+) levels and the mitochondrial membrane potential (DeltaPsi(m)), was decreased in A-549 cells. Overall, our results demonstrated that curcumin treatment causes cell death by activating pathways inducing G2/M-phase arrest and apoptosis.     

Serostatus cutoff levels and fold increase to define seroresponse to recombinant vesicular stomatitis virus – Zaire Ebola virus envelope glycoprotein vaccine: An evidence-based analysis

The recombinant vesicular stomatitis virus – Zaire Ebola virus envelope glycoprotein (rVSVΔG-ZEBOV-GP) vaccine is a live recombinant vesicular stomatitis virus (VSV) where the VSV G protein is replaced with ZEBOV-GP. To better understand the immune response after receiving the rVSVΔG-ZEBOV-GP vaccine, the current analyses evaluated different definitions of seroresponse that differentiate vaccine and placebo recipients enrolled in a placebo-controlled clinical trial (PREVAIL; NCT02344407) in which a subset of the study participants had elevated baseline titers. Alternative values for serostatus cutoff (SSCO; 200–500 EU/mL) and/or fold rise (two- to five-fold) were applied to compare their ability to distinguish between participants receiving rVSVΔG-ZEBOV-GP or placebo. The results indicate that an SSCO of 200 EU/mL can be used to define seropositivity at baseline (i.e. pre-vaccination). The use of dual criteria of the same SSCO (200 EU/mL) together with a two-fold rise in antibody level from baseline provided the definition of seroresponse that maximized the statistical significance between vaccine recipients and placebo recipients post-vaccination.Clinical trial registration: NCT02344407.     

SF1a-PRLR和ΔS2 SF1a-PRLR对乳腺癌MCF-7细胞增殖和microRNA表达的影响

目的：探讨过表达SF1a-PRLR及其变体ΔS2 SF1a-PRLR基因对人乳腺癌MCF-7细胞增殖和microRNA表达的影响。方法：利用同源重组技术将SF1a-PRLR和ΔS2 SF1a-PRLR cDNA分别重组至慢病毒，再将携带不同基因的重组病毒，即空病毒、携带SF1a-PRLR cDNA和ΔS2 SF1a-PRLR cDNA的慢病毒分别转染MCF-7细胞，经嘌呤霉素多次筛选得到稳定转染细胞株MCF7-con（对照组）、MCF7-SF1a-PRLR（SF1a组）、MCF7-ΔS2 SF1a-PRLR（ΔS2 SF1a组），将3组稳定转染细胞株培养后进行细胞增殖实验，提取总RNA进行小分子RNA高通量测序。结果：增殖实验结果显示，培养48 h时，对照组、SF1a组和ΔS2 SF1a组的D（492）值分别为1.85±0.29、2.24±0.26、2.57±0.23，3组之间两两比较，差异均有统计学意义（P均 < 0.05）。测序结果显示，各组间microRNA表达均有显著差异，SF1a组与对照组比较，差异表达的microRNAs共有176个（32个表达上调，144个表达下调）；ΔS2 SF1a组与对照组相比，差异表达的microRNAs共206个（52个表达上调，154个表达下调）；ΔS2 SF1a组与SF1a组比较，差异表达的microRNA共5个（miR-4454、miR-215-5p、miR-797、miR-622表达上调，miR-210-5p表达下调），其中，miR-210-5p在对照组、SF1a组、ΔS2 SF1a组中的相对表达水平分别为66.18、31.67、13.07，两两比较均具有显著差异（P均 < 0.05）。结论：过表达SF1a-PRLR或ΔS2 SF1a-PRLR均能促进人乳腺癌MCF-7细胞的体外增殖且显著影响人乳腺癌MCF-7细胞的microRNA表达，两者对大部分microRNA表达的影响作用相似，仅对miR-4454等5个microRNAs的表达具有显著影响。     

Emergence of the less common cannabinoid Δ8-Tetrahydrocannabinol in a doping sample

Δ⁸-Tetrahydrocannabinol (Δ⁸-THC) as isomer of the well-known Δ⁹-THC has a similar mode of action, and the potency was estimated to be two thirds compared with Δ⁹-THC. Content of Δ⁸-THC in plant material is low, but formulations containing Δ⁸-THC in high concentrations are gaining popularity. Δ⁸-THC is to be regarded as prohibited substance according to the Prohibited List of the World Anti-Doping Agency (WADA). Contradictory results between initial testing procedure and confirmatory quantitation for 11-Nor-9-carboxy-Δ⁹-tetrahydrocannabinol (Δ⁹-THC-COOH) of a doping control sample gave rise for follow-up testing procedures. After alkaline hydrolysis and liquid–liquid extraction, the sample was analyzed by high-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) using isocratic elution instead of gradient elution, which is used for standard procedure. Isocratic elution resulted in two peaks instead of one using gradient elution. Both peaks showed same fragmentation. Using certified reference materials, one peak could be assigned to Δ⁹-THC-COOH and the other one with higher intensity to the less common 11-Nor-9-carboxy-Δ⁸-Tetrahydrocannabinol (Δ⁸-THC-COOH) in a concentration of approximately 1200 ng/ml. As complementary method, gas chromatography tandem mass spectrometry (GC-MS/MS) can also be used for identification. Here Δ⁸- and Δ⁹-THC-COOH can be distinguished by chromatography and by fragmentation. Additional investigations of doping control samples containing Δ⁹-THC-COOH revealed the simultaneous presence of Δ⁸-THC-COOH in low concentrations (0.22–8.91 ng/ml) presumably due to plant origin. Percentage of Δ⁸-THC-COOH varies from 0.05 to 2.83%. In vitro experiments using human liver microsomes showed that Δ⁸-THC is metabolized in the same way as Δ⁹-THC.