Epstein—Barr病毒潜伏膜蛋白（LMP）基因免疫的初步研究

利用基因免疫技术,将重组质粒ＰＢＳ－ＬＭＰ－Ｈｙｇ直接注入ＢＡＬＢ／Ｃ小鼠骨骼肌中,于第２、４、８周,用间接免疫荧光法检测鼠血清中抗ＥＢ病毒潜伏膜蛋白（ＬＭＰ）特异抗体,结果表明,所有免疫小鼠（５／５）均产生特异体体,且抗体滴度随时间变化逐渐增高。     

Death Receptor 5 and Neuroproliferation

Tumor necrosis factor-related apoptosis-inducing ligand or Apo2 ligand is a member of the tumor necrosis factor superfamily of cytokines that induces apoptosis upon binding to its death domain-containing transmembrane receptors, death receptors 4 and 5 (DR4, DR5). However, DR5 is also expressed in the developing CNS where it appears to play a role unrelated to apoptosis, and instead may be involved in the regulation of neurogenesis. We report on the distribution of DR5 expression in mouse hippocampus, cerebellum, and rostral migratory stream (RMS) of olfactory bulb from embryonic (E) day 16 (E16) to postnatal (P) day (P180). At E16, DR5-positive cells were distributed widely in embryonic hippocampus with strong immunostaining in the developing dentate gyrus. In newborn hippocampus, DR5-positive cells were predominantly located in proliferative zones, such as dentate gyrus, subventricular zone, and RMS. After postnatal day 7 (P7), the number of DR5-positive cells decreased, and cells with intense fluorescence were primarily restricted to the subgranular layer (SGL), although the granular cell layer showed weak fluorescence. After P30, only few DR5-positive cells were found in SGL, and mature granule cells were negative for DR5 expression. To address whether DR5 expression is a restricted to progenitor cells and newborn neurons, we performed 5-bromo-deoxyuridine labeling. We report that proliferative cells in the SGL selectively express DR5, with lower levels of expression in cells positive for doublecortin, a marker of newborn neurons. In addition, the stem cells in intestine, cerebellum, and RMS were also demonstrated to be DR5-positive. In the meantime, in cerebellum, DR5-positive cells were also positive for glial fibrillary acidic protein, a marker of proliferative Bergmann cells. We conclude that DR5 is selectively expressed by neuroprogenitor cells and newborn neurons, suggesting that the DR5 death receptor is likely to play a key role in neuroproliferation and differentiation.     

基于26S rDNA D1/D2序列分析酱香型白酒酒醅中酵母菌的群落结构

【目的】比较分析不同发酵阶段的酱香型白酒北大仓酒醅中酵母菌的群落结构。【方法】酒醅样本采集自黑龙江省北大仓白酒不同阶段的发酵窖池,采用平板分离技术获得大量酵母菌纯培养物;基于26S rDNA D1/D2区域的碱基序列,准确鉴定酒醅中的酵母菌;根据酵母菌的数量变化、种类组成、相对频率、多样性指数及其相似性系数,研究酱香型北大仓白酒酒醅中酵母菌的群落结构特征。【结果】北大仓白酒酒醅中酵母菌数量在酿造过程中的变化,遵循着"升高-降低-升高-降低"的规律;第1轮"升高-降低"的过程表现出急剧的"速升速降"特点,而第2轮"升高-降低"的过程则具有相对来说比较温和的"缓升缓降"特征。酒醅内的酵母菌鉴定为8属13种,总体多样性指数处于较高的水平,发酵初期酵母菌多样性指数逐渐增加,最高的多样性指数(1.89)出现在发酵第5 d的酒醅内;然后又逐渐下降,发酵至第11 d时降至最低(0.66);酒醅发酵至13 d时开始直至发酵末期,多样性指数呈现出波动性变化。北大仓白酒酒醅中酵母菌的种类组成总体来说比较接近,大多数情况下相似性系数都高于0.5,说明在白酒酿造过程中酵母菌的组成和分布处于一个相对稳定的状态。对于北大仓白酒酒醅内存在的常见酵母菌来说,Issatchenkia orientalis、Pichia kudriavzevii和Saccharomyces cerevisiae可能在酿造过程中发挥更重要的作用。【结论】北大仓等酱香型白酒的酒醅内存在着丰富的酵母菌资源,阐明酒醅内酵母菌的群落结构可以为解析酱香型白酒的发酵机理提供基础数据和理论基础。     

Cloning and characterization of two types of ubiquitin genes from Gracilariopsis lemaneiformis (Gracilariales, Rhodophyta)

Two types of ubiquitin genes were isolated from the marine red alga Gracilaria lemaneiformis: a ubiquitin-52 amino acid fusion protein gene, and a 6-unit polyubiquitin gene. Alignment of polyubiquitins among three red algae (Gracilaria lemaneiformis, Gracilaria verrucosa, Aglaothamnion neglectum) and other species revealed that there were six ubiquitin repeats in all three red algae polyubiquitins, and that glutamine was the final amino acid residue in the terminal repeat of the polyprotein in the two Gracilaria sequences. Southern blot analysis revealed that both genes were encoded by low-copy number genes. Semi-quantitative RT-PCR was performed to investigate the expression of these two genes in two phases of G. lemaneiformis. The result revealed that the monoubiquitin was phase-relative, and upregulated in tetrasporophytes compared with female gametophytes. The polyubiquitin gene was expressed at similar levels in both phases.     

The distal region and receptor tyrosines of the Epo receptor are non-essential for in vivo erythropoiesis.

The erythropoietin receptor (EpoR) is required for the proliferation and survival of committed erythroid lineage cells. Previous studies have utilized receptor mutations to show the requirement for the distal half of the cytoplasmic domain of the EpoR and receptor tyrosines for activation of signaling pathways potentially critical to Epo function. To extend these studies to in vivo erythropoiesis, we have created two mutant strains of mice. One strain (H) contains a truncation of the distal half of the cytoplasmic domain, while the second strain (HM) contains the same truncation as well as the mutation of the residual tyrosine (Y(343)) to a phenylalanine. Strikingly, both strains of mice are viable, with only slight alterations in constitutive erythropoiesis or in in vitro assays of red cell lineage function. Challenging H mutant mice with continuous injections of Epo results in an erythrocytosis that is not seen in HM mice. The results demonstrate that neither the distal region nor receptor tyrosines are essential for in vivo EpoR function, but contribute to receptor function in a subtle manner.     

The biochemistry of blister fluid from pediatric burn injuries: proteomics and metabolomics aspects

Burn injury is a prevalent and traumatic event for pediatric patients. At present, the diagnosis of burn injury severity is subjective and lacks a clinically relevant quantitative measure. This is due in part to a lack of knowledge surrounding the biochemistry of burn injuries and that of blister fluid. A more complete understanding of the blister fluid biochemistry may open new avenues for diagnostic and prognostic development. Burn insult induces a highly complex network of signaling processes and numerous changes within various biochemical systems, which can ultimately be examined using proteome and metabolome measurements. This review reports on the current understanding of burn wound biochemistry and outlines a technical approach for ‘omics’ profiling of blister fluid from burn wounds of differing severity.     

Rapid quantitation of monoclonal antibody N-glyco-occupancy and afucosylation using mass spectrometry

N-glyco-occupancy and afucoslyation level are two important quality attributes associated with N-glycosylation of therapeutic monoclonal antibodies (mAbs). We report here a fast mass spectrometry-based workflow for quantification of N-glycan site-occupancy and afucoslyation level of mAbs with improved throughput, precision, sensitivity and robustness. This method uses the deglycosylation after the first GlcNAc and inter-chain reduction of the mAbs, followed by liquid chromatography/mass spectrometry (LC-MS) analysis. The entire process can be completed within one hour, which provides a rapid quantitation of N-glyco-occupancy and afucosylation to support high-throughput cell line selection and process development for mAb biopharmaceuticals.     

Angiogenic inhibition reduces germinal matrix hemorrhage

The germinal matrix of premature infants is selectively vulnerable to hemorrhage within the first 48 h of life. To assess the role of vascular immaturity in germinal matrix hemorrhage (GMH), we evaluated germinal matrix angiogenesis in human fetuses and premature infants, as well as in premature rabbit pups, and noted active vessel remodeling in all three. Vascular endothelial growth factor (VEGF), angiopoietin-2 and endothelial cell proliferation were present at consistently higher levels in the germinal matrix relative to the white matter anlagen and cortical mantle. On that basis, we asked whether prenatal treatment with either of two angiogenic inhibitors, the COX-2 inhibitor celecoxib, or the VEGFR2 inhibitor ZD6474, could suppress the incidence of GMH in premature rabbit pups. Celecoxib treatment decreased angiopoietin-2 and VEGF levels as well as germinal matrix endothelial proliferation. Furthermore, treatment with celecoxib or ZD6474 substantially decreased the incidence of GMH. Thus, by suppressing germinal matrix angiogenesis, prenatal celecoxib or ZD6474 treatment may be able to reduce both the incidence and severity of GMH in susceptible premature infants.     

CIC通道的生物学及相关疾病

CIC（voltage-gated chloride channel)通道是迄今发现的唯一电压门控氯离子通道,在细胞兴奋性调节,细胞容积调节和跨上皮物质转运等生理过程的调节中发挥重要作用,本文讨论了目前已经发现的CIC通道的分类,分布,结构和功能,以及与其有关的致病机制。