Forskolin's effect on transient K current in nudibranch neurons is not reproduced by cAMP

Forskolin, a diterpene extracted from Coleus forskolii, stimulates the production of cAMP in a variety of cells and is potentially an important tool for studying the role of cAMP in the modulation of neuronal excitability. We studied the effects of forskolin on neurons of nudibranch molluscs and found that it caused characteristic, reversible changes in the amplitude and waveform of the transient K current, IA, and also activated an inward current similar to the cAMP-dependent inward current previously described in molluscan neurons. Forskolin altered the time course of IA activation and inactivation but did not affect the voltage dependence or the reversal potential of the current. IA normally inactivates exponentially, but in forskolin the time course of inactivation can be fit by the sum of 2 exponentials with an initial rate that is faster than the control and a final rate that is much slower. On depolarization in forskolin, IA begins to activate at the normal rate, but a slower component of activation is also seen. The changes in IA in the nudibranch cells were qualitatively different than the changes caused by forskolin in Aplysia bag cell neurons (Strong, 1984). Experiments were performed to determine whether these effects of forskolin require cAMP. Intracellular injection of cAMP, application of membrane-permeable analogs of cAMP, application of phosphodiesterase inhibitors, and intracellular injection of the active catalytic subunit of cAMP-dependent protein kinase did not affect the amplitude or waveform of IA. Also, the changes in IA that are caused by forskolin were not prevented or reversed by intracellular injection of an inhibitor of cAMP-dependent protein kinase. Cyclic AMP did, however, activate inward current at voltages near the resting potential. We conclude that the changes in IA and the activation of inward current represent separate affects of forskolin. The inward current appears to depend on an increase in intracellular cAMP, while the changes in IA do not. These experiments show that, in addition to activating adenylate cyclase, forskolin may have a separate direct affect on the transient K current.     

Arteriovenous fistula between the hepatic artery and the hepatic vein

A patient is presented with multiple vascular anomalies in the branches of the celiac axis as well as in the portal vein and its branches. Apparently, unique in the literature is the presence of a large arteriovenous fistula between the hepatic artery and one of the hepatic veins. The anomalies are presumed to be congenital in origin.     

Major surgery in von Willebrand's disease

Two patients with von Willebrand's disease underwent major surgery, the first had aortic valve replacement and the second a total hip replacement. Clinically, the best practical test for monitoring the dose of cryoprecipitate necessary to maintain haemostasis was the bleeding time. The response to coagulation factor replacement in von Willebrand's disease is extremely variable, and it is necessary to maintain close coagulation monitoring until the patient's surgical condition is satisfactory for discharge from hospital.     

THE INFLUENCE OF PLASMA PROTEIN ON THE CHLORIDE CONTENT OF THE CEREBROSPINAL FLUID

1. When the plasma protein of dogs is lowered by plasmapheresis, the concentration of chloride and sodium in the plasma and the cerebrospinal fluid tends to become the same, a diminishing of the usual disparity which exists in the presence of a normal plasma protein. 2. This is in accord with the theory that the cerebrospinal fluid is a dialysate, with the choroid plexus acting as a simple dialyzing membrane.     

Rheumatism in childhood and adolescence

Indian Journal of Pediatrics -     

PLS—紫外分光光度法同时测定复方阿斯匹林片中三组分含量

本文研究了复方阿斯匹林片中阿斯匹林、非那西丁和咖啡因含量同时测定的紫外分光光度法的最佳实验条件,并简述偏最小二乘法(PLS)在多组分同时测定中的基本原理和应用。三组分模拟试样回收率平均值的置信区间分别为100.1±0.23%,100.0±0.25%和100.1±0.33%(置信度95%)。PLS法是一种理想的多组分测定方法,计算速度较快,结果更准确可靠,尤其适用于成批试样的分析,为微机控制的紫外可见分光光度计提供了一种新方法。     

Treatment of invasive bladder cancer by cisplatin and radiation in patients unsuited for surgery

Seventy patients with muscle-invading bladder carcinoma (clinical stages T2 to T4) who were not candidates for cystectomy were treated with combined cisplatin and full-dose external-beam radiation on a multi-institutional prospective protocol from 1980 through 1985. Thirty-six patients are alive, all but three without evidence of cancer. The complete response rate is 77% in the 62 patients completing planned irradiation and 70% for all patients. Among the complete responders, 73% are currently maintained, and this group has a significantly higher four-year survival than those not having a complete response and those with recurrence of disease--57% vs 11%. The observed high complete response rates in patients in all stages and the high survival rates suggest irradiation plus cisplatin therapy offers an important therapeutic gain over radiation therapy alone for invasive cancer of the bladder. These results encourage further evaluation of combining cisplatin-based, multidrug chemotherapy with irradiation in patients with locally very-advanced bladder tumors who are not suited for surgery.     

医用聚乳酸类高分子材料的应用

目的:阐述医用聚乳酸类高分子材料的需求,综述聚乳酸类高分子材料在生物医学领域的应用,并对其在医学领域的应用前景进行展望。资料来源:应用计算机检索ACS美国化学学会数据库2000-01/2006-12关于医用聚乳酸类高分子材料的文章,检索词“polylactide”;利用Elsevier Science全文电子期刊数据库2000-01/2006-12进行检索,检索词“polylactide”和全文检索“Medical polymeric material”。同时利用计算机检索中国期刊全文数据库1994-01/2005-12的相关文章,限定文章语言种类为中文,检索词“聚乳酸类医用高分子材料”。资料选择:对资料进行初审,纳入标准:①关于聚乳酸类医用高分子材料的需求。②医用聚乳酸类高分子材料的合成及应用。排除标准:重复性研究。资料提炼:共收集到符合上述要求的文献100篇,排除70篇重复性研究。30篇符合纳入标准:其中6篇关于聚乳酸类医用高分子材料的需求,24篇关于医用聚乳酸类高分子材料的合成及应用。资料综合:聚乳酸是一种具有良好的生物相容性和可生物降解的聚合物,最终的降解产物是二氧化碳和水,对人体无毒、无刺激。目前,聚乳酸类材料产品在医学领域广泛用于药物控制释放载体、组织工程、骨内固定、修复、手术缝合线、人造皮肤以及三维多孔支架等。结论:医用聚乳酸类高分子材料有非常广阔的应用前景,今后研究的重点是研发高效低成本的聚乳酸制备方法,合成适应于不同医疗或其他用途的、具有优良生物相容性的聚乳酸共聚物高分子材料。