Nano-purification of raw semen minimises oxidative stress with improvement in post-thaw quality of buffalo spermatozoa

The study consisted of application of anti-ubiquitin antibodies (Abs)-coated iron oxide-nanoparticles (IONPs) for minimisation of oxidative stress to contemporary live spermatozoa from the raw semen. Round-shaped IONPs (12.09 ± 0.91 nm) after two-stage functionalisation (silanisation and pegylation) were conjugated with Abs. Four aliquots from each of the 24 ejaculates (4 buffalo bulls) formed Control (Group I) and treatment (II, III and IV) groups; each containing 150 ± 25 million dead/damaged spermatozoa. IONPs-Abs complex were added at ratio of 1:1 (0.5 µg/ml), 1:2 (1.0 µg/ml) and 1:4 (2.0 µg/ml), respectively, in Groups II, III and IV. The semen quality parameters showed improvement at lag-stage (post-nano-purification before processing for cryopreservation). The mean post-thaw motility (%) in Group IV was found to be greater (p < .05) than Group I. Moreover, the overall DNA integrity (%) at post-thaw stage was improved in the nano-purified semen samples. The value of malondialdehyde was greater (p < .001) in Group I than Groups II, III and IV. The mean total antioxidant capacity and superoxide dismutase (U/mg protein) activity values in Group IV was greater (p < .05) than Group I. The study results show that IONPs conjugated with anti-ubiquitin Abs at 2.0 µg/ml can be an effective dose for depletion of dead/damaged spermatozoa from buffalo ejaculates to minimise oxidative stress.     

From Capsids to Complexes: Expanding the Role of TRIM5α in the Restriction of Divergent RNA Viruses and Elements

An evolutionary arms race has been ongoing between retroviruses and their primate hosts for millions of years. Within the last century, a zoonotic transmission introduced the Human Immunodeficiency Virus (HIV-1), a retrovirus, to the human population that has claimed the lives of millions of individuals and is still infecting over a million people every year. To counteract retroviruses such as this, primates including humans have evolved an innate immune sensor for the retroviral capsid lattice known as TRIM5α. Although the molecular basis for its ability to restrict retroviruses is debated, it is currently accepted that TRIM5α forms higher-order assemblies around the incoming retroviral capsid that are not only disruptive for the virus lifecycle, but also trigger the activation of an antiviral state. More recently, it was discovered that TRIM5α restriction is broader than previously thought because it restricts not only the human retroelement LINE-1, but also the tick-borne flaviviruses, an emergent group of RNA viruses that have vastly different strategies for replication compared to retroviruses. This review focuses on the underlying mechanisms of TRIM5α-mediated restriction of retroelements and flaviviruses and how they differ from the more widely known ability of TRIM5α to restrict retroviruses.     

Reduced miR-9 and miR-181a expression down-regulates Bim concentration and promote osteoclasts survival

Tibial plateau fractures are often the result of blunt trauma and are associated with severe soft-tissue injury. Operative management of high-energy fractures remains difficult and challenging because the injuries often associated with serious complications. MicroRNAs (miRNAs) are the class of short noncoding single-stranded RNA molecules that negatively regulate gene expression. miRNAs contribute to every step of osteogenesis from embryonic bone development to maintenance of adult bone tissue, and disturbed miRNAs expression are identified related to osteoporosis, osteosarcoma, post-traumatic arthritis and bone remodeling. But our understandings about the roles of miRNAs in tibial plateau fractures repairing process are rare. In this study, we first detect seven candidate miRNAs expression in the SF cells of the mouse model. The results indicated that miR-9 and miR-181a were down-regulated significantly five days after injury. By using dual luciferase assay and western blot, we confirmed that the expression of Cbl is repressed by miR-9 and miR-181a. Meanwhile, the amount of ubiquitinated Bim was raised and the total Bim was reduced by miRNA inhibitors. Further functional study indicated that reduced miR-9 and miR-181a expression can active RAW264.7 cells migration ability and raise the primary mouse osteoclasts survival rate in vitro. To our understood, this is the first study about the function of disturbed miRNAs in the tibial plateau fracture mouse model, and may expand our understanding about post tibial plateau fracture recover and post-traumatic sequelae generation.     

结直肠癌中Cks1, P27Kip1和Skp2蛋白的表达

目的:探讨Cks1在结直肠癌发生及其在Skp2调节P27Kip1降解过程中的作用. 方法:应用流式细胞术测定正常结直肠黏膜、结直肠腺瘤和结直肠癌组织中Cks1, P27Kip1和Skp2蛋白的表达. 结果:由正常结直肠黏膜、结直肠腺瘤到结直肠癌Cks1, Skp2表达呈上升趋势(P＜0.05),P27Kip1表达呈下降趋势(P＜0.05). 结直肠癌中Cks1, Skp2表达与P27Kip1表达呈负相关(r=-0.752, P＜0.05; r=-0.746, P＜0.05);Cks1与Skp2呈正相关(r=0.845, P＜0.05). 结直肠癌中Cks1的表达与肿瘤分化程度相关(P＜0.05),而与淋巴结转移及Dukes分期不相关(P＞0.05). 结论:Cks1可能参与了结直肠癌的发生;结直肠癌中Cks1可能参与了Skp2调节P27Kip1泛素化降解过程.     

泛素-蛋白酶体系统与缺血性脑损伤

泛素-蛋白酶体系统可选择性降解细胞内蛋白类物质,具有控制炎症反应、信号传导和基因表达等多种功能,参与了缺血性脑损伤的病理学过程。研究表明,脑缺血后应用蛋白酶体抑制剂可有效改善神经细胞变性、缩小脑梗死灶体积、减少白细胞浸润和降低NF-κB活性,发挥神经保护作用。文章综述了泛素-蛋白酶体系统与缺血性脑损伤的关系及其相关机制,以期为临床上更有效地干预缺血性脑损伤提供新的策略。     

小鼠Usp25基因的雄激素反应元件的克隆与功能鉴定

目的我们前期研究中进行全基因组表达谱检测发现在雄激素受体（androgen receptor,Ar）基因睾丸支持细胞特异性敲除小鼠（S-Ar^-/y）睾丸组织中泛素特异性蛋白酶25（ubiquitin specific peptidase 25,usp25）基因表达较低。本研究的目的是了解雄激素及其受体是否可以作用于Usp25基因,并测定其雄激素反应元件（androgen-responsive element,ARE）。方法采用RT-qPCR方法检测Usp25基因表达量。通过生物信息学预测脚25基因上游可能的ARE,构建Usp25基因ARE报告质粒pGLP／Usp25。在TM4细胞中,采用荧光素酶报告系统分析雄激素及其受体对Usp25基因ARE活性的调控作用。结果在S-Ar^-/y小鼠睾丸组织中矾p25基因表达量比在野生型小鼠中显著降低。在TM4细胞中睾酮可以显著提高Usp25基因表达量。在TM4细胞中,雄激素可以显著提高pGLP／Usp25的荧光素酶活性。结论Usp25基因表达可以被雄激素睾酮激活,Usp25基因第一内含子519至1102bp区域含有ARE,可以调控启动子的转录水平。     

泛素蛋白酶体途径在急性早幼粒细胞白血病中作用的研究进展简

急性早幼粒细胞白血病（acute promyelocytic leukemia,APL）以表达PML-RARα为特征.泛素-蛋白酶体途径在全反式维甲酸及三氧化二砷诱导其降解过程中发挥重要作用,并参与细胞周期调节、转录调控等过程.深入研究该通路在APL中的作用有助于明确部分药物的起效机制及开拓APL的临床治疗思路.本文就泛素-蛋白酶体途径的组成、泛素-蛋白酶体途径介导的蛋白质修饰在APL中的作用、泛素化途径相关药物在APL中的应用进行综述.     

Expressions of genes related to genome stability and DNA repair in nasopharyngeal carcinoma clustering families

Objective： The aim of the study was to observe the expressions of genes related to genome stability and DNA repair in the members of nasopharyngeal carcinoma （NPC） clustedng families. Methods： In the Zhongshan City where there is highly incidence rate of NPC, we chose the members of the NPC clustering families as objects, and the patients of nasopharyngitis and NPC as the control group. We isolated the RNA from the nasopharyngeal tissue, and synthesized its cRNA, the genome stability and DNA repair genes chip technique, chemiluminescent detection and real-time fluorescence quantita- tive technique were used to examine the genome stability and DNA repair genes in the nasopharyngeal tissue. Results： More genome stability and DNA repair genes were up-regulated in the members of the NPC clustering families than the NPC patients, and the range of up-regulated was high, with the over up-regulated 100 times genes including TEP1, MSH4, PMS2LI. Fewer genome stability and DNA repair genes were down-regulated in the members of the NPC clustering families than the NPC patients, the ubiquitin genes almost were down-regulated, the results also could be confirmed by real-time fluorescence quantitative PCR. Conclusion： There are specially expression character of genome stability and DNA repair genes in the members of NPC clustering families.