2-12烷基-6-甲氧基环己基-2,5-二烯-1,4-二酮(DMDD)抗弥漫大B淋巴瘤的作用及机制*

目的:探讨2-12烷基-6-甲氧基环己基-2,5-二烯-1,4-二酮(DMDD)抗弥漫大B淋巴瘤(DLBCL)的作用及分子机制。方法:动物实验取4周龄BALB/C小鼠,分5组,20只/组,腹股沟注射DLBCL细胞株OCI-LY19细胞1 × 10⁷ cells/ml 每只0.1 ml,两天后分别灌胃0、1、5、25、125 mg/kg剂量的DMDD,1次/2天,给药的第18日,杀10只小鼠,取瘤组织称重,记录剩余小鼠的生存期。细胞实验取OCI-LY19细胞加入96孔培养板,每孔100 μl 1×10⁵ cells/ml,分别加入100 μl DMDD使其终浓度分别为0、1、5、25和125 μmol/L,作用0、24、48和72 h,设三复孔,MTS法检测细胞增殖活性;根据细胞增殖实验结果,选择0 μmol/L、5 μmol/L和25 μmol/L的DMDD作为后续用药浓度作用OCI-LY19细胞24 h,流式细胞仪分析凋亡率,hoechst染色观察细胞核型,JC-1染色观察线粒体膜电位,LDH释放实验评估药物细胞毒性,qPCR、Western blot分析基因转录和表达水平。结果:动物实验表明:与0 mg/kg用药组比,1～125 mg/kg DMDD能抑制小鼠瘤组织生长并延长其生存期(P＜0.01)。细胞实验表明:DMDD用药组OCI-LY19细胞增殖活性明显降低、凋亡水平显著增加(P＜0.01),细胞核出现碎裂、凝集和凋亡小体及线粒体膜电位下降,LDH释放率显著增加(P＜0.01),细胞内caspase-3和bax基因的转录表达和IκBα的磷酸化水平显著上调,bcl-2、bcl-xL、jak2和stat3基因的转录和蛋白表达水平明显受抑(P＜0.01)。结论:DMDD通过抑制JAK2/STAT3和NF-κB信号通路中JAK2、STAT3和p-IκBα的表达,下调BCL-2/BAX、活化Caspase-3,最终激活OCI-LY19细胞线粒体凋亡的内源性通路而促进了DLBCL细胞凋亡,抑制了OCI-LY19细胞增殖,具有抗DLBCL的作用。     

Fancm基因敲除小鼠构建及其表型分析

目的构建范可尼贫血通路Fancm基因敲除小鼠,研究Fancm基因缺失对小鼠生理功能,特别是雄性生殖器官的影响。方法采用CRISPR/Cas9技术,获得Fancm基因敲除小鼠。分析FANCM蛋白在野生型和Fancm^-/-小鼠睾丸组织中的表达。统计Fancm^-/-小鼠的出生率、体重、性别比例及子代生育情况,分析血液常规指标。组织形态学研究雄性Fancm^-/-小鼠睾丸生理病理表型。结果敲除Fancm基因ATG区域,获得稳定遗传的C57BL/6背景Fancm^-/-小鼠。Fancm^-/-小鼠睾丸中FANCM蛋白表达完全丢失。Fancm^-/-小鼠无明显的胚胎致死现象,但雌性Fancm-/-小鼠数目显著少于雄性Fancm^-/-小鼠。同窝Fancm^-/-小鼠比较野生型体重无明显区别,部分血常规指标有显著性差异。Fancm^-/-小鼠有明显的生殖能力缺陷。雄性Fancm^-/-小鼠睾丸有显著的发育缺陷,其生精细胞凋亡增加、细胞周期阻滞,影响睾丸发育与精子的生成。结论成功获得稳定遗传C57BL/6背景Fancm^-/-小鼠,Fancm基因参与小鼠的生长发育,特别是雄性生殖器官功能的维持及调控。     

问天湖水质监测及其治理对策

对武汉生物工程学院问天湖湖水的水质进行监测,其中氨氮0.03～0.19 mg/L,总磷0.08～1.01 mg/L,化学需氧量(COD)22.26～58.22 mg/L,溶解氧(DO)2.79～4.31 mg/L,pH 7.60～8.25。由监测结果可知,pH值在正常范围内,氨氮与DO达标,总磷与COD超标,问天湖水质污染原因主要是有机物污染及磷引起的富营养化现象,并对如何改善水质提出了相应的治理对策。     

Inbreeding levels and prey abundance interact to determine fecundity in natural populations of two species of wolf spider

Long-term effective population size is expected, and has been shown, to correlate positively with various measures of population fitness. Here we examine the interacting effects of population size (as a surrogate for genetic factors) and prey consumption rates (as a surrogate for environmental quality) on fecundity in two sympatric species of wolf spider, Rabidosa punctulata and Rabidosa rabida. Population size was estimated in each of seven genetically isolated populations in each of 3 years using mark-recapture methods. Fecundity was estimated as the mean number of live offspring produced by ∼15 females sampled from each population of each species each year for 3 years. Prey consumption rates were estimated by sampling ∼300 spiders per population per year and assaying the proportion of spiders with prey. Larger populations have higher fecundity and more genetic diversity than smaller populations. Variation among populations in fecundity for a given year could be attributed most strongly to differences in population size, with variation in prey consumption rates and the interaction between population size and prey consumption playing smaller but still important roles. During the most stressful environmental conditions, the smallest populations of both species experienced disproportionately low-fecundity rates, more than doubling the estimated number of lethal equivalents during those years. The evidence presented in this paper for inbreeding-environment interactions at the population level and further evidence for a log-linear relationship between population size and fitness have important implications for conservation.     

Proteomic identification of nitrated brain proteins in amnestic mild cognitive impairment: a regional study

Oxidative stress is an imbalance between the level of antioxidants and oxidants in a cell. Oxidative stress has been shown in brain of subjects with mild cognitive impairment (MCI) as well Alzheimer's disease (AD). MCI is considered as a transition phase between control and AD. The focus of the current study was to identify nitrated proteins in the hippocampus and inferior parietal lobule (IPL) brain regions of subjects with amnestic MCI using proteomics. The identified nitrated proteins in MCI brain were compared to those previously reported to be nitrated and oxidatively modified in AD brain, a comparison that might provide an invaluable insight into the progression of the disease.     

Yeast Prions: Evolution of the Prion Concept

Prions (infectious proteins) analogous to the scrapie agent have been identified in Saccharomyces cerevisiae and Podospora anserina based on their special genetic characteristics. Each is a protein acting as a gene, much like nucleic acids have been shown to act as enzymes. The [URE3], [PSI⁺], [PIN⁺] and [Het-s] prions are self-propagating amyloids of Ure2p, Sup35p, Rnq1p and the HET-s protein, respectively. The [β] and [C] prions are enzymes whose precursor activation requires their own active form. [URE3] and [PSI⁺] are clearly diseases, while [Het-s] and [β] carry out normal cell functions. Surprisingly, the prion domains of Ure2p and Sup35p can be randomized without loss of ability to become a prion. Thus amino acid content and not sequence determine these prions. Shuffleability also suggests amyloids with a parallel in-register β-sheet structure.Key Words: Ure2, Sup35, Rnq1, HETs, PrP, prion, amyloid     

Cryptic variation in butterfly eyespot development: the importance of sample size in gene expression studies

Previous studies have shown that development can be robust to variation in parameters such as the timing or level of gene expression. This leads to the prediction that natural populations should be able to host developmental variation that has little phenotypic effect. Cryptic variation is of particular interest because it can result in selectable phenotypes when "released" by environmental or genetic factors. Currently, however, we have little idea of how variation is distributed between genes or over time in pattern formation processes. Here we survey expression of Notch (N), Spalt (Sal), and Engrailed (En) during butterfly eyespot determination to better understand how pattern formation may vary within a population. We observed substantial heterochronic variance in the progress of spatial expression patterns for all three proteins, suggesting some degree of developmental buffering in eyespot development. Peak variance for different proteins was found at both early and late stages of development, contrasting with previous models suggesting that the distribution of variance should be more temporally focused during pattern formation. We speculate that our observations are representative of a standing reservoir of cryptic variation that may contribute to phenotypic evolution under certain circumstances. Our results also provide a strong cautionary message that gene expression studies with limited sample sizes can be positively misleading in terms of inferring expression pattern time series, as well as for making cross-species phylogenetic comparisons.