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11.
模拟5000m中度缺氧时,大鼠右室功能显著加强,而左室功能加强不显著;左右心室肌原纤维Ca2+,Mg2+-ATP酶活性下降,肌球蛋白同功酶V2和V3百分含量增加,V1百分含量减少。8000m重度缺氧时,右室功能减弱,但无统计学意义,左室功能减弱有显著性;ATP酶活性和同功酶的变化超过5000m组。此外,右室ATP酶活性与PAP呈反比且有显著性,左室ATP酶活性与CASP虽也呈反比但无显著性;右室同功酶V3百分含量与PAP呈正比,左室同功酶V3百分含量与CASP不呈比例。上述结果表明,因短期突发严重缺氧引起的心肌供氧不足对左心室心肌的直接损伤作用大于右心室心肌。 相似文献
12.
Serum-free culture of rat keratinocytes 总被引:2,自引:0,他引:2
Hirosuke Oku Chikara Kumamoto Tomoyuki Miyagi Takanori Hiyane Junichi Nagata Isao Chinen 《In vitro cellular & developmental biology. Animal》1994,30(8):496-503
Summary Procedures for the serum-free culture of rat keratinocytes have been established. Basal cells prepared from epidermis of newborn
rat were stored in liquid nitrogen and used for primary culture. Among the available media, MCDB 153, developed originally
for human keratinocyte (HK) culture, was the best for the development of serum-free formulation. To grow rat keratinocytes,
bovine serum albumin was arbitrarily substituted for the macromolecule supplements needed for HK culture, i.e. fetal bovine
serum protein or bovine pituitary extract. Qualitative and quantitative adjustment of supplements was thereafter made to support
rapid cell growth. Satisfactory cell growth was achieved in the optimized medium of MCDB 153 supplemented with growth factors
and amino acids: insulin (10 μg/ml), hydrocortisone (0.1 μg/ml), epidermal growth factor (25 ng/ml), calcium chloride (0.2
mM), histidine (0.23 mM), isoleucine (0.05 mM), tryptophane (0.015 mM), threonine (1.25 mM), tyrosine (0.031 mM), alanine (4.08 mM), and albumin (2 mg/ml). This optimized culture system was superior to the original HK culture condition for rapid growth
of rat keratinocytes. Under our condition, cells grew as a monolayer, becoming confluent, but without stratification, and
were passaged 2 to 3 times without any changes in morphology. The serum-free formulation allows us to control more accurately
the concentrations of biomolecules in the medium including lipids and hormones, and therefore will be suitable for the study
focusing on lipid metabolism or hormonal regulation of rat keratinocytes. 相似文献
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Plasmids containing a Pseudomonas sp. strain 109 extracellular lipase gene (lipL) lacking NH2-terminal sequence and a lipase modulator gene (limL) lacking the NH2-terminal hydrophobic region were constructed and expressed independently in Escherichia coli by using the T7 promoter expression vector system. Recombinant LipL (rLipL) was produced as inclusion bodies, whereas recombinant LimL (rLimL) was present as a soluble protein. During in vitro renaturation of the purified rLipL inclusion bodies after they had been dissolved in 8 M urea, addition of rLimL was essential to solubilize and modulate rLipL. The solubility and activity of rLipL were influenced by the rLimL/rLipL molar ratio; the highest level of solubility was obtained at an rLimL/rLipL ratio of 4:5, whereas the highest activity level was obtained at an rLimL/rLipL ratio of 4:1. After renaturation, rLipL and rLimL were coprecipitated with anti-rLipL antibody, indicating the formation of an rLipL-rLimL complex. Activity of the native lipase purified from Pseudomonas sp. strain 109 was also inhibited by rLimL. By Western blotting (immunoblotting) with anti-rLimL antibody, native LimL was detected in Pseudomonas cells solubilized by sarcosyl treatment. LimL was purified from Pseudomonas sp. strain 109, and the NH2-terminal amino acid sequence was determined to be NH2-Leu-Glu-Pro-Ser-Pro-Ala-Pro-. We propose that to prevent membrane degradation, LimL weakens lipase activity inside the cell, especially in the periplasm, in addition to modulating lipase folding. 相似文献
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Shigenori Tanaka Takanori Nakamura Takashi Morita Sadaaki Iwanaga 《Biochemical and biophysical research communications》1982,105(2):717-723
Exposure of amebocytes to bacterial endotoxins (lipopolysaccharides, LPS) results in the activation of the coagulation system, which consists of several protein components. During the separation of these components, a potent anticoagulant, named tentatively anti-LPS factor, which inhibits the endotoxin-mediated coagulation reaction, was found in both amebocytes from the hemolymphs of and . The principle purified partially from amebocyte lysate had a molecular weight less than 10,000, as judged with the ordinary gelfiltration experiment. It inhibited specifically the activation of factor B, which has recently been characterized to be a coagulation factor highly sensitive to LPS, but it did not inhibit the activities of the active factor B and the active clotting enzyme separated from the lysate. The inhibitory activity of anti-LPS factor disappeared almost completely by the treatments with pronase-P and subtilisin, suggesting its polypeptide-like substance, but it resisted to a boiling treatment. A possible site of the anticoagulant action on the coagulation system was discussed. 相似文献
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锯缘青蟹精子发生的超微结构 总被引:13,自引:0,他引:13
采用透射电镜观察锯缘青蟹精子发生过程中超微结构的变化,结果表明:精原细胞椭圆形,染色质分布于核膜周围,胞质中具嵴少的线粒体,内质网小泡等。初级精母细胞染色质呈非浓缩状,胞质中具众 内质网小泡,特殊的膜系及晶格状结构。次级精母细胞核质间出现由内质小泡聚集成的腔。 相似文献
20.
抗凝活性肽RGD226基因构建、表达、产物纯化及活性分析 总被引:3,自引:0,他引:3
通过PCR法 ,将来源于蛇毒蛋白质eristostatin中的一段含有RGD(Arg Gly Asp)序列的十三肽(SRVARGDWNDDYS)的基因 ,以一个无胰岛素活性但保留天然免疫原性的胰岛素原突变体(PJG4 0 1)基因为模板 ,置换其B2 8和A1位之间的连接肽基因 ,构建成了能展示RGD功能序列的人源化分子 (RGD2 2 6 )的基因 .通过该基因在大肠杆菌中的表达、产物分离纯化 ,得到高纯度RGD2 2 6 .该RGD肽对由ADP诱导的体外人血小板聚集的半抑制浓度IC50 为 2 2 3μmol L .其胰岛素免疫活性是PJG4 0 1的 15 1% ,提示其在一定程度上保留了胰岛素原的免疫原性 .其受体结合活性不到PJG4 0 1的 0 1% ,说明其胰岛素的生物活性基本丧失 .动物实验证实 ,RGD2 2 6在延长小鼠出血时间上具有较明显的作用 相似文献