异落新妇甙的结构研究

从百合科菝葵属植物土茯苓(Smilaxg labra Roxb.)根茎的乙醇提取物中分得一个新的天然化合物(I),命名为异落新妇甙(isoastilbin)。根据元素分析,UV,IR,¹H-NMR,¹³C-NMR,2DNMR及FAB-MS,确定化合物I的结构为5,7,3',5'-四羟基二氢黄酮醇-3-O-α-L-鼠李糖甙。     

Activity-dependent Decay of Early LTP Revealed by Dual EPSP Recording in Hippocampal Slices from Young Rats

The early maintenance of long-term potentiation (LTP) was studied in the CA1 region of hippocampal slices from 12- to 18-day-old rats in a low-magnesium solution (0.1 mM). The α-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA) and N-methyl-D-aspartate (NMDA) receptor-mediated components of the field excitatory postsynaptic potential were estimated in parallel using early and late measurements of the composite potential. At the normal test stimulus frequency of 0.1 Hz, LTP was seen initially as a predominant increase in the AMPA component, but converted, via a substantial decay of this component and a gradual growth of the NMDA component, into nearly equal changes of the two components. Interrupting the test stimulation for 10 min, changing the test stimulus frequency to 1/60 Hz after LTP induction, or using a test stimulus frequency of 1/60 Hz during the entire experiment significantly reduced the decay of the potentiation of the AMPA component while enhancing the potentiation of the NMDA one. The ratio between the magnitudes of the two excitatory postsynaptic potential (EPSP) components showed a decaying time course that was independent of the manipulations used. Application of the NMDA antagonist D(-)-2-amino-5-phosphonopentanoic acid (50μM) after LTP induction stabilized the LTP of the AMPA component until washout was started. On the other hand, the phosphatase inhibitor okadaic acid (1 μM) resulted in decay of the potentiation of both EPSP components back to around baseline and altered the time course of the ratio between the components. Our results show that the early maintenance of LTP is controlled in an activity-dependent and NMDA-dependent manner. This process accelerates the decay of LTP of both AMPA and NMDA components in parallel, suggesting that it is similar to homosynaptic long-term depression, although it operates at the normal test stimulus frequency. The data support a scenario in which LTP ensues as a selective AMPA receptor modification and subsequently converts to another modification, possibly a presynaptic one.     

Treatment of pyoderma gangrenosum

Critical to the proper management of pyoderma gangrenosum are correct diagnosis, identification and treatment of any underlying disorder, and the proper choice of topical and systemic therapy. Many agents are available for the treatment of pyoderma gangrenosum. We review the current therapeutic options, their efficacy and side effects, and we offer some guidelines for their proper selection.     

婴儿肝炎综合征63例临床分析

对我科1989-1990年中收治的婴儿肝炎综合征63例的临床表现、合并症、治疗等方面进行了分析。笔者认为婴儿肝炎综合征为一组临床症候群。病因诊断有其重要性。腹部B超检查有助于肝炎和胆道闭锁的鉴别,可作为常规检查方法。并认为用肾上腺皮质激素治疗有效。     

Raf-1 kinase,epidermal growth factor receptors,and mutant ras proteins in colonic carcinomas

Epidermal growth factor receptors (EGFR) andras mutations are known to play a significant role in controlling cell growth and tumor promotion. Both of them transmit mitogenic signals to the nucleus by activation of Raf-1 kinase. In this study, the expression of EGFR and mutant Ras proteins, and, for the first time, the expression, phosphorylation and kinase activity of Raf-1 kinase have been determined in paired samples of colorectal cancer and mucosa. The tumor and mucosa samples did not differ significantly with regard to Raf-1 kinase content and activity. A major difference between tumors and mucosa was found, however, in the phosphorylation of Raf-1. Most of the mucosa samples (13/20), but only 1/20 of the cancer samples, contained hyperphosphorylated Raf-1. EGFR were significantly (p=0.0025) decreased in the tumors. The decreased phosphorylation of Raf-1 in colonic carcinomas could be the result of activation of Raf-1 phosphatases or inactivation of kinases phosphorylating Raf-1. New forms of treatment based on EGFR overexpression do not seem to be suitable for the majority of colonic cancers.This work was supported by the state of Baden-Württemberg (Verbundforschungsprojekt: Aufklärung von Mechanismen der Tumorentstehung und Tumorabwehr).     

Clusterlike Headache as a First Sign of Brain Metastases of Lung Cancer

We report on a patient with clusterlike headache and multiple brain metastases of lung cancer. Initially, cluster headache was suggested clinically by characteristic symptoms without any focal central nervous system signs. However, magnetic resonance imaging demonstrated multiple brain metastases. It is possible that tumor necrosis factor may have played a role in initiating the clusterlike headache.     

Renal abnormalities in children with hypertrophic pyloric stenosis —fact or fallacy?

Retrospective review of the abdominal ultrasound (US) examination of 274 children studied for hypertrophic pyloric stenosis (HPS) was undertaken to determine if there is an increased incidence of renal disease as previously reported. Five major abnormalities were detected in the 126 children with HPS. Three lesions were newly diagnosed and two had been diagnosed previously. Five children had abnormalities classified as minor or normal variants. Renal abnormalities were found in six of the 148 children who did not HPS. Only three of these were newly diagnosed and medically important. Eight children without HPS had minor abnormalities or normal variants of the kidneys. Newly diagnosed medically important renal lesions were present in 2.4% of children screened for HPS. The incidence of the finding was the similar in children with and without HPS.Paper presented at 1992 RSNA meeting     

Polymyositis-dermatomyositis:25 years of follow-up of 50 patients disease course, treatment, prognostic factors

Therapeutic results were analysed in 50 patients, including 17 with polymyositis (PM) and 30 with dermatomyositis (DM). All patients were treated with prednisone (Encorton, Polfa) and 47% of patients with PM and 73% with DM required combined treatment with prednisone and cytostatic agents, mostly with cyclophosphamide (Endoxan G.D.R.). Long-term treatment monitored with the clinical status led to remissions persisting after treatment discontinuation in 17.6% of PM patients and 24.2% of DM patients. In 64.7% of PM patients and 57.6% of DM patients regression of the clinical signs of the disease was achieved but these patients required further treatment. No information was obtained on 5 cases. Four DM patients died. The cumulative 17-year survival rate of PM patients was 100%, and that of DM patients was 78.8% . In 45 follow-up cases, the mortality was 8.9%. Side effects of the combined treatment included most frequently mucosal candidiasis (22.2%), transient leucopenia (14.8%) and recurrent respiratory tract infections (11.1%). In 5 cases liver biopsy was done and histological examination disclosed moderate fatty, glycogen and vacuolar degeneration of the hepatocytes. The statistical analysis of prognostic factors such as the diagnosis of PM or DM, sex, age at disease onset, disease duration till diagnosis establishing and beginning of treatment, fever, dysphagia, circulatory and respiratory changes, leucocytosis nad ESR at the beginning of the disease showed that sex (female), older age at disease onset and respiratory system changes may be accepted as poor prognosis factors.     

促甲状腺素释放激素类似物YM14673对小鼠学习记忆的影响

采用小鼠跳台法评价促甲状腺素释放激素类似物ＹＭ１４６７３（ｉｐ１ｍｇ·ｋｇ－１）对正常成年小鼠被动回避学习记忆成绩的影响．结果表明ＹＭ１４６７３对东莨菪碱，氯霉素和乙醇造成的小鼠记忆获得，巩固及再现障碍均有明显的改善作用．