Capacitively coupled electrical stimulation of bovine growth plate chondrocytes grown in pellet form

Pellets formed from isolated bovine growth plate chondrocytes were grown in various capacitively coupled electrical fields. The signals chosen were 0, 10, 100, 250, 500, 750, 1,000, and 1,500 V peak-to-peak, 60 kHz. The effect on cell proliferation and matrix production of these different voltages was determined by [3H]thymidine and [35S]sulfate uptake, respectively, Cyclic AMP assays were done to determine if increases in either thymidine or sulfate uptake were associated with changes in cAMP levels. Significantly increased cell proliferation occurred at 500, 750, and 1,000 V peak to peak. The calculated electric fields were 1.5 to 3.0 x 10(-2) V/cm. Proliferation was significantly inhibited at 1,500 V peak-to-peak with a calculated field of 4.5 x 10(-2) V/cm. Little if any change was seen in cAMP levels at 30 or 60 min following application of the appropriate electric signals.     

高效液相色谱法测定硫酸奈替米星注射液的含量

目的采用高效液相色谱法测定硫酸奈替米星及注射液的含量。方法以μ-Diamonsil—C18为分析柱，流动相为1．5％的磷酸二氢钾-乙睛，流速为1．0ml／min，检测渡长为205nm。含量测定用峰面积外标法。结果硫酸奈替米星在0．1—1．6mg／ml浓度范围内呈现良好线性关系，r=0．9998．平均回收率为99．5％，RSD=0．4％（n=9）。结论本方法操作简便、快速，结果准确可靠，重现性好，均能很好地满足质量控制的要求，为开辟氨基糖苷类抗生素含量测定的仪器提供了一定借鉴。     

ALTERATION OF CHOLESTEROL SULFATE IN HUMAN SERA DURING THE COURSE OF PREGNANCY

Objective To determine the concentrations of cholesterol sulfate ( CS) in human sera and pla-cental villi during the course of pregnancy. And to analyze its inhibitory activity on thrombin and further characterize the functional significance of CS. Methods The concentrations of CS were determined by thin-layer chromatog-raphy (TLC) on 60 cases of normal pregnant women and 30 cases of normal placental villi. The effect of CS in human sera on the activity of thrombin was analyzed. Results The concentrations of CS in human sera gradually increased from the first to third trimester of gestation with a correlation coefficient of 0. 69, and a correlation between the concentration of CS and weeks of gestation (P <0. 01). CS was also contained in the placental villi, and its concentrations at the second and third trimester of gestations were 4. 7 and 6. 2-fold of that at the first trimester of gestation. CS inhibited the activity of thrombin. Conclusion Placental CS is one of the sources of CS in the serum , pr     

CDP-c、硫酸镁联用对大鼠短暂脑缺血的神经保护作用

目的 研究胞二磷胆碱（CDP-c）、硫酸镁联用对大鼠试验性短暂局灶脑缺血的神经保护作用.方法 用大脑中动脉栓塞（MCAO）法制作短暂性（90min）局部脑缺血模型,观察CDP-c、硫酸镁单用及不同剂量联用7d后,Caspase-3阳性细胞数、神经功能缺损及脑梗死体积的变化.结果 和对照组相比,CDP-c、硫酸镁单用及两药联用组脑梗死体积较小,Caspase-3表达细胞数较少,并有统计学意义.两药联用组脑梗死体积均比单用组小,Caspase-3表达细胞数亦较两药单用组少（P＜0.05）.两药联用组相比各项指标均无显著意义（P＞0.05）.结论 CDP-c和硫酸镁单用对试验性短暂脑缺血模型可能具有神经保护作用.CDP-c与硫酸镁合用对短暂性试验性局灶脑缺血的神经保护可能有协同作用,并且可以减少各药的用量.     

医用硫酸钙在家兔腰椎融合模型中的成骨能力

[目的]通过与自体髂骨进行比较,评价医用硫酸钙单独应用的成骨能力,并探讨其可能的成骨机理。[方法]建立家兔腰椎后外侧融合模型,以自身作为对照,双侧横突间植骨,左侧植入硫酸钙颗粒,右侧植入自体髂骨。于术后3、6、12周行X线、CT及组织学检查。[结果]术后3周,硫酸钙尚可见残留颗粒,自体骨完全降解;植骨区域内均可见到大量的破骨细胞,并有血管纤维组织长入。术后6周,硫酸钙完全降解,影像学检查两者之间没有明显的差异,表现为局部骨密度增高,新骨成形;组织学检查两侧植骨区内均为大量的透明软骨形成,自体髂骨植骨区内可见散在的骨小梁结构。术后12周,组织学及影像学上二者没有任何的差别,两侧形成的骨组织与家兔的椎体骨组织结构相同。[结论]医用硫酸钙作为骨移植替代材料,除了具有良好的骨传导性外,硫酸钙可能还具有骨诱导性,其成骨能力与自体髂骨相当,医用硫酸钙单独应用可以取得良好的融合效果。     

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。     

Morphine-3-glucuronide: hyperglycemic and neuroendocrine potentiating effects

The greater potency of morphine-6-glucuronide (M6G) as well as the inactivity of morphine-3-glucuronide (M3G) with respect to the antinociceptive effects of the parent molecule, morphine (MOR), have been well established. It has been suggested that M3G is an antagonist of MOR's antinociceptive and respiratory depressive effects. The present study addressed the central nervous system (CNS) interaction of these opiate metabolites on their metabolic and hormonal effects. Whole body glucose kinetics were assessed on conscious, chronically catheterized, unrestrained rats. M3G (5 μg) or H₂O (5 μl) was injected intracerebroventricularly (i.c.v.) 15 min prior to the bolus administration of H₂O (5 μl), M6G (1 μg), or MOR (80 μg). i.c.v. M3G (5 μg) resulted in behavioral excitation, hyperglycemia (+50%), stimulation of glucose rate of appearance (R_a; +100%), glucose rate of disappeaance (R_d; +70%), and metabolic clearance rate (MCR; +33%) within 30 min after injection with no alterations in hormone concentrations. i.c.v. M6G and MOR produced progressive hyperglycemia with significantly high catecholamine and corticosterone levels. M3G pretreatment resulted in enhanced elevations in plasma glucose levels (+52% and +18%), plasma lactate (+138% and +108%), norepinephrine (+96% and +30%), and epinephrine (+62% and +67%) in response to both i.c.v. MOR and M6G administration. These findings suggest a non-opiate and non-hormonal mechanism for M3G-induced hyperglycemia. In contrast, the metabolic and hormonal responses to i.c.v. M6G and MOR are associated with elevations in catecholamine and corticosterone levels, which are remarkably enhanced by M3G pretreatment, most likely through accelerated catecholamine release. Our findings suggest a modulatory role for MOR glucuronidation, not only by rendering it inactive, as in the case of M3G, but by an interplay of the metabolic effects of the parent molecule and its metabolite     

Patch testing with beryllium alloy samples in guinea pigs

An experimental study was conducted in guinea pigs for the predictive assessment of the beryllium alloy hazard in occupational exposure of the skin to beryllium compounds. Guinea pigs were sensitized to beryllium sulfate according to the maximized Magnusson and Kligman test, and challenged with beryllium alloys and metallic copper, beryllium and aluminum samples. Results showed a delayed skin hypersensitivity reaction in 30 to 60% of pre-sensitized guinea pigs challenged with copper-beryllium alloys and aluminum-beryllium alloy. An inflammatory follicular reaction was induced by copper in both controls and pre-sensitized guinea pigs.     

Colonic Drug Delivery: Enhanced Release of Indomethacin from Cross-Linked Chondroitin Matrix in Rat Cecal Content

Pharmaceutical Research -