新疆罗布麻生态类型及其纤维品质研究

新疆塔里木河及叶尔羌河流域是我国能够提供商品精干罗布麻的主要地区。由于野生罗布麻生长高矮不一,形态各异,与其纤维品质的相关性较大。通过40个株号的罗布麻植株形态和纤维长度等的的测定,分析各类型罗布麻的纤维长度和罗布麻植株各部分纤维长度情况。研究结果表明：罗布红麻高杆类型主茎纤维最长,罗布麻放牧类型纤维最短。罗布麻植株各部分纤维长度是主茎上的大于分枝,主茎中部的最长,基部和梢部最短。为野生罗布麻资源开发利用提科学依据。     

基于不同标度伪氨基酸组成预测脂肪酶的类型

从序列出发预测某蛋白质是否为脂肪酶以及属于哪种脂肪酶具有重要的理论和应用价值.提出了基于Z标度和T标度的伪氨基酸组成方法提取序列特征值,采用了k-近邻算法回答上述问题.经参数选择后,三种方法在各自最优运行参数下,其1倍交叉验证的结果为:对脂肪酶和非脂肪酶预测精度分别为92.8%、91.4%和91.3%;对脂肪酶类型预测的精度分别为92.3%、90.3%和89.7%.其中基于Z标度伪氨基酸组成效果最佳.基于T标度的次之,但均明显优于其他6种常见的特征值提取方法,并对其可能的原因进行了探讨.     

Ibuprofen Exerts Antiepileptic and Neuroprotective Effects in the Rat Model of Pentylenetetrazol-Induced Epilepsy via the COX-2/NLRP3/IL-18 Pathway

Neurochemical Research - Epilepsy is one of the most common diseases of the central nervous system. Recent studies have shown that a variety of inflammatory mediators play a key role in the...     

双歧杆菌的分离驯化与鉴定

本文报道了从重庆市正常人群肠道中筛选出的５株双歧杆菌经厌氧→微氧→有氧的方式进行了数百次传代驯化,最后选送３株送国家认可的法定菌种鉴定单位认可为：８６３２１两歧杆菌、８６０４３青春双歧杆菌和８６２７４婴儿双歧菌。它的成功为我们进一步开发系列双歧产品奠定了很好基础。     

Oxidative stress and NF-κB signaling are involved in LPS induced pulmonary dysplasia in chick embryos

Inflammation or dysbacteriosis-derived lipopolysaccharides (LPS) adversely influence the embryonic development of respiratory system. However, the precise pathological mechanisms still remain to be elucidated. In this study, we demonstrated that LPS exposure caused lung maldevelopment in chick embryos, including higher embryo mortality, increased thickness of alveolar gas exchange zone, and accumulation of PAS⁺ immature pulmonary cells, accompanied with reduced expression of alveolar epithelial cell markers and lamellar body count. Upon LPS exposure, pulmonary cell proliferation was significantly altered and cell apoptosis was inhibited as well, indicating a delayed progress of pulmonary development. LPS treatment also resulted in reduced CAV-1 expression and up-regulation of Collagen I, suggesting increased lung fibrosis, which was verified by Masson staining. Moreover, LPS induced enhanced Nrf2 expression in E18 lungs, and the increased reactive oxygen species (ROS) production was confirmed in MLE-12 cells in vitro. Antioxidant vitamin C restored the LPS induced down-regulation of ABCA3, SP-C and GATA-6 in MLE-12 cells. Furthermore, LPS induced activation of NF-κB signaling in MLE-12 cells, and the LPS-induced decrease in SP-C expression was partially abrogated by blocking NF-κB signaling with Bay-11–7082. Bay-11–7082 also inhibited LPS-induced increases of ROS and Nrf2 expression. Taken together, we have demonstrated that oxidative stress and NF-κB signaling are involved in LPS induced disruption of pulmonary cell development in chick embryos.     

Transport functions and expression analysis of vacuolar membrane aquaporins in response to various stresses in rice

The vacuole, a multifunctional organelle of most plant cells, has very important roles in space filling, osmotic adjustment, storage and digestion. Previous researches suggested that aquaporins in the tonoplast were involved in vacuolar functions. The rice genome contains 33 aquaporin genes, 10 of which encode tonoplast intrinsic proteins (TIPs). However, the function of each individual TIP isoform and the integrated function of TIPs under various physiological conditions remain elusive. Here, five rice TIP members were characterized with water and/or glycerol transport activities using the Xenopus oocyte expression system. OsTIP1;2, OsTIP2;2, OsTIP4;1 and OsTIP5;1 possessed water transport activity. OsTIP1;2, OsTIP3;2 and OsTIP4;1 were demonstrated with glycerol transport activity. Rice TIP expression patterns under various abiotic stress conditions including dehydration, high salinity, abscisic acid (ABA) and during seed germination were investigated by real-time PCR. OsTIP1s (OsTIP1;1 and OsTIP1;2) were highly expressed during seed germination, whereas OsTIP3s (OsTIP3;1 and OsTIP3;2) were specifically expressed in mature seeds with a decrease in expression levels upon germination. The results of this research provided a functional and expression profiles of rice TIPs.     

Plant regeneration via somatic embryogenesis of Elymus sibiricus cv. ‘chuancao No. 2’

The mature seeds, mesocotyls, and young leaf tips of Elymus sibiricus L. cv. ‘chuancao No. 2’ were cultured on Murashige and Skoog (MS) medium supplemented with 5.0 mg/L 2,4-dichlorophenoxyacetic acid (2,4-d) and 0.05 mg/L kinetin in the dark at 26°C, the calluses were produced. The rate of callus regeneration depended on the explants source and plant growth regulators. Plants regenerated from whitish-yellow-coloured compact nodular callus formed after subculturing for 8 weeks. Higher frequency (54%) of shoot differentiation was obtained from the embryo tissues of mature seed than from either mesocotyls (24%) or young leaf tip tissues (6%) when these calluses from different types of explants were cultured on plant regeneration medium containing half strength MS salts supplemented with 0.1 mg/L kinetin, 1.5 mg/L 2,4-D and 20 g/L sucrose. The green plants were rooted within 6 weeks in the root regeneration medium, and over 97% of these soil-established plants were obtained in the greenhouse when potted in a sand and peat mixture medium.     

千金子不同极性部位对酪氨酸酶活性的影响

测定千金子醇提物不同极性部位对酪氨酸酶活性的影响。以L-酪氨酸为底物,采用比色法测定千金子不同极性部位对酪氨酸酶的抑制率。得到了千金子醇提物的乙酸乙酯相、正丁醇相和水相的半数抑制率(IC50值)分别为0.150 mg/mL,0.813 mg/mL,7.570 mg/mL,并对乙酸乙酯相进一步分离得到七叶内酯,其IC50值0.103 mg/mL。结果表明千金子中起到酪氨酸酶抑制性的物质为七叶内酯,主要分布在乙酸乙酯相中。为千金子中酪氨酸酶抑制性物质的筛选提供科学依据。     

蛇毒类凝血酶calobin在毕赤酵母中的表达

蛇毒类凝血酶是临床上防治血栓栓塞性疾病的有效药物。参照朝鲜蝮蛇(Agkistrodon caliginosus,Korean Viper)类凝血酶calobin基因序列(GenBank AccessionNo.U32937.1),将人工合成的calobin基因克隆到酵母表达载体pPICZαA,于毕赤酵母中表达,得到了分子量约为32kD的重组calobin蛋白,经甲醇诱导培养,表达产物可获得3.5g/L的高表达量。重组蛋白经过阴离子交换柱Q-Sepharose Fast Flow和分子筛Sephacryl-S-100凝胶过滤层析等纯化步骤进行了初步纯化。纯化后的重组calobin可以在纤维蛋白原平板上形成水解圈,经SDS-PAGE实验显示,重组蛋白能水解纤维蛋白原的Aα链,产生一条约40kD左右的降解带。在实验中未能发现重组calobin对纤维蛋白原的凝固作用。     

Synthesis and Activity Evaluation of Nasopharyngeal Carcinoma Inhibitors Based on 6‐(Pyrimidin‐4‐yl)‐1H‐indazole

Human nasopharyngeal carcinoma is a common head and neck malignancy with high incidence in Southeast Asia and Southern China. It is necessary to develop safe, effective and inexpensive anticancer agents to improve the therapeutics of patients with nasopharyngeal carcinoma. A series of small molecular compounds based on 6‐(pyrimidin‐4‐yl)‐1H‐indazole were synthesized and evaluated for antiproliferative activities against human nasopharyngeal carcinoma cell lines SUNE1. Compounds 6b , 6c , 6e and 6l showed potent antiproliferative activities similar to positive control drug cisplatin in vitro with lower nephrotoxicity than it. N‐[4‐(1H‐Indazol‐6‐yl)pyrimidin‐2‐yl]benzene‐1,3‐diamine ( 6l ) was selected for further study. It was found that 6l induced mitochondria‐mediated apoptosis and G₂/M phase arrest in SUNE1 cells. Furthermore, compound 6l at 10 mg/kg can suppress the growth of an implanted SUNE1 xenograft with a TGI% (tumor growth inhibition) value of 50 % and did not cause serious side effects in BALB/c nude mice. This study suggests that 6‐(pyrimidin‐4‐yl)‐1H‐indazole derivatives are a series of small molecule compounds with anti‐nasopharyngeal carcinoma activities.