线性变温法研究硫酸链霉素粉针剂的稳定性

用线性变温法对硫酸链霉素粉针的稳定性进行了测定,得出25℃时的降解反应速度常数 k_(25)为1.744×10~(-6)h~(-1)、化学反应的表观活化能为107.9kJ/mol,25℃时贮存的 t_(0.9)为6.9年。     

Independent integration of genes controlling the invasive properties and streptomycin resistance of enteropathogenic strain Escherichia coli 0124

CrossingEscherichia Coli K12 Hfr AB313 with an enteropathogenic strain ofE. coli of the serological group 0124 yielded recombinants which had lost their invasiveness. The loss of invasiveness of these recombinants was not due to the acquisition of genes controlling resistance to streptomycin.I. P. Pavlov First Leningrad Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR N. N. Zhukov-Verezhnikov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 82, No. 9, pp. 1144–1145, September, 1976.     

肺靶向硫酸链霉素明胶微球的制备

目的:用生物可降解材料明胶制备肺靶向硫酸链霉素明胶微球.方法:用乳化法制备微球,正交试验设计考察影响制备工艺的因素,用扫描电子显微镜观察微球表面形态,用红外光谱分析确证含药微球的形成.并对所制备的硫酸链霉素明胶微球的粒径及其分布、载药量、包封率、稳定性等进行了研究.结果:微球形态圆整,药物确己存于微球中.微球的平均粒径为12.269 μm,粒径在5.0～25.0 μm的微球占总数的91.5%,达到肺靶向要求.载药量为42.6%,包封率为53.8%.最佳工艺条件重现性好.经37℃、RH75%放置3个月,其含量、外观形态及大小基本不变.结论:该微球制备工艺稳定,可用于肺靶向注射剂的研究.     

mTOR inhibition with rapamycin causes impaired insulin signalling and glucose uptake in human subcutaneous and omental adipocytes

Rapamycin is an immunosuppressive agent used after organ transplantation, but its molecular effects on glucose metabolism needs further evaluation. We explored rapamycin effects on glucose uptake and insulin signalling proteins in adipocytes obtained via subcutaneous (n=62) and omental (n=10) fat biopsies in human donors. At therapeutic concentration (0.01 μM) rapamycin reduced basal and insulin-stimulated glucose uptake by 20-30%, after short-term (15 min) or long-term (20 h) culture of subcutaneous (n=23 and n=10) and omental adipocytes (n=6 and n=7). Rapamycin reduced PKB Ser473 and AS160 Thr642 phosphorylation, and IRS2 protein levels in subcutaneous adipocytes. Additionally, it reduced mTOR-raptor, mTOR-rictor and mTOR-Sin1 interactions, suggesting decreased mTORC1 and mTORC2 formation. Rapamycin also reduced IR Tyr1146 and IRS1 Ser307/Ser616/Ser636 phosphorylation, whereas no effects were observed on the insulin stimulated IRS1-Tyr and TSC2 Thr1462 phosphorylation. This is the first study to show that rapamycin reduces glucose uptake in human adipocytes through impaired insulin signalling and this may contribute to the development of insulin resistance associated with rapamycin therapy.     

HPLC法测定链麻滴鼻液中硫酸链霉素和盐酸麻黄碱的含量

目的建立测定链麻滴鼻液中硫酸链霉素和盐酸麻黄碱含量的高效液相色谱法,消除焦亚硫酸钠对硫酸链霉素含量测定的影响。方法色谱柱为Diamonsil C18柱(250mm×4.6mm,5μm);流动相为0.014mol·L-1庚烷磺酸钠的0.05mol·L-1磷酸二氢钾溶液-乙腈(78∶22);检测波长硫酸链霉素195nm,盐酸麻黄碱207nm;流速1.0mL·min-1。结果硫酸链霉素质量浓度在44.40³10.80μg·mL-1范围内,与其峰面积呈良好的线性关系。(r=0.999 8,n=7),平均回收率为103.4%(RSD=3.4%);盐酸麻黄碱质量浓度在20.224310.80μg·mL-1范围内,与其峰面积呈良好的线性关系。(r=0.999 8,n=7),平均回收率为103.4%(RSD=3.4%);盐酸麻黄碱质量浓度在20.224⁸0.896μg·mL-1范围内,与其峰面积呈良好的线性关系(r=0.999 9,n=7),平均回收率为99.5%(RSD=1.0%)。结论该方法专属性强、测定结果准确、精密度高、线性好,加入甲醛能够消除辅料中焦亚硫酸钠对硫酸链霉素含量测定的影响。     

结核杆菌耐药性调查与基因突变分析

目的了解结核分支杆菌耐药性与基因突变情况,分析耐药表型与基因突变的相关性。方法从临床标本中分离培养、鉴定结核分支杆菌;应用药敏试验、单链探针反向杂交试验技术(LiPA)和基因测序分析结核分支杆菌耐药性与基因突变情况。结果50株结核分支杆菌中,12株耐异烟肼(INH),7株耐利福平(RFP),15株耐链霉素(SM),2株耐乙胺丁醇(EMB)。LiPA检测耐RFP菌株,4株rpoB基因531位TCG→TTG突变;耐INH菌株中5株KatG基因315位AGC→ACC突变;耐SM菌株中6株、SM敏感株1株rpsl基因43位AAG→AGG突变,1株耐SM菌株rpsl基因88位AAG→AGG突变;rrs基因未检测到突变;1株耐EMB菌株与1株EMB敏感株的embB基因306位发生ATG→GTG突变。结论本市结核分支杆菌的耐药性增加的趋势显著,加强监测与综合干预非常必要。     

硫酸链霉素注射液无菌检查法试验验证

目的：探讨硫酸链霉素注射液的无菌检查方法，考察其抑菌作用及测定方法的可行性。方法：采用薄膜过滤法．通过无菌验证试验确定无菌检查方法的有效性。结果：含供试品各容器中的试验菌均生长良好。结论：通过验证试验的无菌检查方法可行，所得结果可靠，适合该药品的无菌检查。     

Effect of removal of cumulus cells from one-cell mouse embryos on in vitro development

The effects of the removal of cumulus cells from fertilized mouse oocytes (one-cell embryos) and the presence of streptomycin in culture medium on in vitro development were studied. Ham's F-10 medium with (0.075 g/liter) or without streptomycin was supplemented with human serum (15%). Cumulus-intact embryos were harvested from oviducts after mice were superovulated with pregnant mare's serum gonadotropin (PMSG) and human chorionic gonadotropin (hCG). Hyaluronidase (300 IU/ml) was used to remove the cumuli. Embryos were cultured (i) with cumulus/without streptomycin (n=238), (ii) with cumulus/with streptomycin (n=185), (iii) without cumulus/with streptomycin (n=210), and (iv) without cumulus/without streptomycin (n=218). Embryonic development was assessed 24, 96, and 120 hr after initiation of culture. Percentage two cells and percentage small or expanded blastocysts were not different (P>0.05) among experimental groups. Percentages hatched blastocysts for the four groups were (i) 36±8 and 54±7, (ii) 35±8 and 55±6, (iii) 19±5 and 42±6, (iv) 23±5 and 47±5 at 96 and 120 hr, respectively. Percentages all (small, expanded, and hatched combined) blastocysts were (i) 74±5 and 74±5, (ii) 74±9 and 72±5, (iii) 56±6 and 63±5, and (iv) 61±5 and 63±5 at 96 and 120 hr, respectively. A greater (P<0.05) percentage of embryos developed to blastocysts and hatched by 96 and 120 hr, when they were cultured with the cumulus intact. There was no effect of streptomycin on embryonic development. Cumulus cells may act as nurse cells during a critical stage of the development of the embryo.     

Reduction in the formation of carcinogen-induced transformed foci by pencillin G sodium in the C3H/10T1/2 CL8 cell lines.

The C3H/10T1/2 CL8 cell line is being widely used to study mechanisms of malignant transformation in vitro. As currently employed, the standard assay system uses a combination of penicillin (100 I.U./ml) and streptomycin (50 micrograms/ml) to reduce the occurrence of bacterial contamination. The penicillin component of this mixture has been discovered to cause a reduction in the number of transformed foci which develop after exposure of cells to MCA, DMBA and X-rays. This reduction is dose dependent; 500 I.U./ml virtually eliminates transformation, while 100 I.U./ml causes an approximate 50% decrease in the number of foci. This effect does not appear to be due to overt toxicity and is largely reversible on removal of the antibiotic. Gentamicin (25 micrograms/ml) causes no reduction in the formation of transformed foci when compared to cultures maintained in antibiotic-free medium and offers the advantages of chemical stability, a wider spectrum of antibacterial activity in comparison with penicillin/streptomycin and, in addition, is active against many mycoplasma. It is suggested that future studies with this cell line should ideally be performed without antibiotics or should employ Gentamicin for antibacterial protection.     

基于主元分析和模糊模型的链霉素发酵过程建模

基于主元分析和模糊模型 ,提出了一种简单而有效的链霉素发酵过程产物浓度的预报方法 .该方法采用主元分析压缩关联程度高且含有测量噪声的实际工业生产数据 ,筛选出影响产物浓度的主要过程变量 ,构造了模糊分段线性模型的产物浓度估计器 .与线性多元回归模型相比 ,模糊模型更适合作为间歇发酵过程的状态估计器 .