KPC1 expression and essential role after acute spinal cord injury in adult rat

KPC1 (Kip1 ubiquitylation-promoting complex 1) is the catalytic subunit of the ubiquitin ligase KPC, which regulates the degradation of the cyclin-dependent kinase inhibitor p27^kip1 at the G1 phase of the cell cycle. To elucidate the expression and role of KPC1 in nervous system lesion and repair, we performed an acute spinal cord contusion injury (SCI) model in adult rats. Western blot analysis showed a significant up-regulation of KPC1 and a concomitant down-regulation of p27^kip1 following spinal injury. Immunohistochemistry and immunofluorescence revealed wide expression of KPC1 in the spinal cord, including expression in neurons and astrocytes. After injury, KPC1 expression was increased predominantly in astrocytes, which highly expressed PCNA, a marker for proliferating cells. Co-immunoprecipitation demonstrated increased interactions between p27^kip1 and KPC1 4 days after injury. To understand whether KPC1 plays a role in astrocyte proliferation, we applied LPS to induce astrocyte proliferation in vitro. Western blot analysis demonstrated that p27^kip1 expression was negatively correlated with KPC1 expression following LPS stimulation. Immunofluorescence analysis showed subcellular localizations of p27^kip1 and KPC1 were also changed following the stimulation of astrocytes with LPS. These results suggest that KPC1 is related to the down-regulation of p27^kip1; this event may be involved in the proliferation of astrocytes after SCI.     

Seasonal occurrence of helminths in the anadromous fish Coilia nasus (Engraulidae): parasite indicators of fish migratory movements

To understand the seasonal migration of the anadromous Coilia nasus , we attempted to identify the parasites infecting C. nasus and determine their seasonal occurrence. From June 2007 to July 2008, a survey of 775 C. nasus individuals from the estuary of the Yangtze River and the coast of the East China Sea revealed more than 7,300 parasites associated with the gills and alimentary tracts of C. nasus . The following 6 helminth taxa were identified, i.e., the monogeneans Heteromazocraes lingmueni and Helciferus tenuis, the digenean Elytrophallus coiliae, the acanthocephalan Acanthosentis cheni , and larvae of the nematodes Anisakis simplex and Contracaecum sp., all of which are marine or brackish-water parasites. The absence of freshwater helminths suggested that the parasites acquired in freshwater may have been accidentally, and easily, lost by the time the fish had reached the estuary and coast. Contrary to seasonal occurrence of the parasites' life cycles, the lowest mean abundance and prevalence of H. lingmueni and A. cheni occurred in August, which suggested the immigration of C. nasus from freshwater to the Yangtze estuary, with lower parasite burdens. The highest mean abundance and prevalence of the nematodes A. simplex and Contracaecum sp. in May and June, and the lowest in August, indicated the arrival of the fish from the coast and the Yangtze River, to the estuary, respectively. These findings suggested that a majority of the fish prepared for spawning migration in the estuary in spring and early summer and returned to the estuary after spawning in the lower and middle reaches of the Yangtze River in late summer.     

siRNA介导的NFBD1表达沉默对HeLa细胞增殖与凋亡的影响

NFBD1,也称MDC1,是1个参与细胞内DNA损伤后细胞应答反应的重要分子．为探讨NFBD1在细胞增殖和凋亡中的作用及其作为分子靶点用于肿瘤治疗的潜在价值,本研究采用siRNA技术抑制NFBD1的表达,并观察了其对人宫颈癌细胞HeLa细胞增殖和细胞凋亡的影响．半定量RT-PCR和蛋白质印迹分析结果表明,筛选到的短链NFBD1 siRNA能有效抑制内源NFBD1的表达,抑制程度约100％．细胞生长曲线分析结果表明,siRNA介导的NFBD1表达沉默导致HeLa细胞生长增殖的显著抑制．FACS分析结果表明,NFBD1表达抑制导致sub-G₁峰的出现,同时蛋白质印迹分析观察到了caspase 3和PARP（poly-ADP-ribose polymerase）的剪接激活,表明NFBD1表达抑制诱发了细胞凋亡．在该凋亡过程中,P-53及其下游靶分子Bax和Puma的表达水平均没有发生明显变化,但Noxa的表达在mRNA和蛋白质水平上均显著上调,强烈提示该凋亡过程很可能是1个不依赖P53的凋亡途径,且Noxa的转录激活在该凋亡过程中可能起着重要作用．这些结果表明,NFBD1参与细胞生长增殖和凋亡的调节,是一个潜在的肿瘤治疗新靶点．     

交变脉冲电场凝胶电泳与植物大分子DNA的制备

介绍了交变脉冲电场凝胶电泳的原理、方法及其在植物大分子ＤＮＡ制备方面的应用     

中国沿海浒苔属rbcL和ITS序列比较及系统进化分析

为阐明中国沿海浒苔的亲缘关系及地理分布特点,采集青岛栈桥、盐城弶港、宁波象山、温州平阳四地浒苔样本,克隆测序得到ITS1、5.8SrDNA和ITS23种不同长度序列片段。四个地区的rbcL目的片段,长度均为1201bp。分析核苷酸差异和遗传距离,采用邻接法建立系统发生树。结果显示,ITS序列进化速率较快,rbcL序列相当保守。ITS区较短,GC含量均在65%以上,5.8SrDNA的CG含量在50%左右,ITS1区的序列差异大于ITS2区。四个地区的浒苔存在一定的地理差异,盐城和青岛的样本间的亲缘关系较近;宁波和温州的样本间的亲缘关系较近。石莼属(Ulva)和浒苔属(Enteromorpha)的物种没有聚成各自独立的分枝,而是相互混合在一起,应是两个亲缘关系相近的属。引起青岛绿潮的海藻很可能是来自盐城海域的Enteromorpha linza或Enteromorpha prolifera。     

噬菌体治疗细菌性感染及其限制因素

近年来,细菌耐药性已成为抗感染领域面临的严峻问题,临床对一些细菌性感染疾病束手无策。噬菌体疗法是一种通过噬菌体裂解细菌来治疗病原菌感染的治疗手段。噬菌体在抗菌领域表现出显著的优越性,成为目前治疗细菌性感染的研究热点。本文对近年来噬菌体治疗动物和人类病原菌感染、限制其临床应用的因素及解决措施进行综述。     

经血管灌流生长抑素对大鼠离体胃运动的抑制作用

采用血管灌流大鼠离体胃模型,探讨生长抑素对胃运动的影响。结果表明：（１）生长抑素能明显抑制胃窦自发和胃动素兴奋的胃运动;（２）生长抑素可抑制离体胃内源性胃泌素释放;（３）抗生长抑素血清和前列腺素合成酶抑制剂消炎痛可阻断生长抑素对胃窦运动的抑制作用。上述结果提示：生长抑素的抑制作用除通过直接作用于生长抑素受体外,还可能通过胃窦局部前列腺素介导来抑制胃的运动。     

Efficient pyruvate production by a multi-vitamin auxotroph of Torulopsis glabrata: key role and optimization of vitamin levels

A multi-vitamin auxotroph, Torulopsis glabrata strain WSH-IP303, which can use ammonium chloride as a sole nitrogen source for pyruvate production, was selected. To optimize pyruvate yield and productivity, a simple but useful, orthogonal design method, was used to investigate the relationship between thiamine, nicotinic acid, pyridoxine, biotin, and riboflavin. Thiamine was confirmed to be the most important factor affecting pyruvate production. When the concentration of thiamine was 0.01 mg/l or 0.015 mg/l, glucose consumption was improved by increasing the nicotinic acid concentration. When the concentrations of nicotinic acid, thiamine, pyridoxine, biotin, and riboflavin were 8.0, 0.015, 0.4, 0.04, and 0.1 mg/l, respectively, pyruvate concentration and yield reached 52 g/l and 0.52 g/g, respectively, in a 48-h flask culture. By employing a combination of the optimum vitamin concentrations, a batch culture was conducted in a 2.5-l fermentor with an initial glucose concentration of 112 g/l; and the pyruvate concentration reached 69 g/l after 56 h (yielding 0.62 g/g).     

Prioritizing human cancer microRNAs based on genes' functional consistency between microRNA and cancer

The identification of human cancer-related microRNAs (miRNAs) is important for cancer biology research. Although several identification methods have achieved remarkable success, they have overlooked the functional information associated with miRNAs. We present a computational framework that can be used to prioritize human cancer miRNAs by measuring the association between cancer and miRNAs based on the functional consistency score (FCS) of the miRNA target genes and the cancer-related genes. This approach proved successful in identifying the validated cancer miRNAs for 11 common human cancers with area under ROC curve (AUC) ranging from 71.15% to 96.36%. The FCS method had a significant advantage over miRNA differential expression analysis when identifying cancer-related miRNAs with a fine regulatory mechanism, such as miR-27a in colorectal cancer. Furthermore, a case study examining thyroid cancer showed that the FCS method can uncover novel cancer-related miRNAs such as miR-27a/b, which were showed significantly upregulated in thyroid cancer samples by qRT-PCR analysis. Our method can be used on a web-based server, CMP (cancer miRNA prioritization) and is freely accessible at http://bioinfo.hrbmu.edu.cn/CMP. This time- and cost-effective computational framework can be a valuable complement to experimental studies and can assist with future studies of miRNA involvement in the pathogenesis of cancers.     

The inhibition of lung cancer cell growth by intracellular immunization with LC—1 ScFv

INTRODUCTIONLung cancer remains the leading cause of can-cer mortaIity in the world, accounting for more thanone sixth of cancer deaths in the world[1]. Antibod-ies have been proved to be a powerful tool fOr thestudy of 1ung cancer. A monoclonal IgM antibody,LC-1, was obtained in our laboratory. It can reactat a high rate with all four pathological types of lungcancers, including lung adenocarcinoma, 1ung squamous carcinoma, large cell lung cancer and smaIlcell lung cancert but not wit…