赛赓啶对 KBV200细胞多药抗性的逆转作用

研究赛赓啶对KB_V200细胞多药抗性的逆转作用及逆转机制。在KB_V200细胞,采用MTT法,测出赛赓啶对长春新碱、阿霉素和鬼臼乙叉甙耐药的逆转系数分别为5.5,2.0和1.9,而对5-氟尿嘧啶、美法仑的细胞毒性作用无明显影响,表明赛赓啶为多药抗性逆转剂。荧光分光光度法测定表明,赛赓啶可使KB_V200细胞内阿霉素蓄积量增加。流式细胞荧光测定显示赛赓啶可增加罗丹明123的蓄积并减慢其外排。免疫细胞化学及狭缝杂交表明赛赓啶不影响KB_V200细胞的P-糖蛋白染色深度和 mdr1 RNA 表达水平。以上结果提示赛赓啶的多药抗性逆转机制是抑制P-糖蛋白泵的功能。     

盘龙七片治疗不稳定性冠心病心绞痛临床观察

对５８例不稳定性冠心病心绞痛患者，用盘龙七片（３８例）及复方丹参片（２０例）治疗，观察治疗前后心电图ＳＴ段，血液流变学及临床症状的变化，结果：盘龙七片组心电图ＳＴ段的缺血变化明业优于复方丹参片组（Ｐ〈０．０１），血浆粘度及纤维蛋白原下降亦明显（Ｐ〈０．０５或Ｐ〈０．０１），结论：盘龙七片虽是一种抗风湿，骨伤的中成药，但同样对治疗不稳定性冠心病心绞痛有一定的疗效。     

MAO-A inhibition in brain after dosing with esuprone, moclobemide and placebo in healthy volunteers: in vivo studies with positron emission tomography

Objective: The aim of the study was to investigate whether or not esuprone binds substantially to MAO-A in the human brain. Methods: In a randomised double-blind placebo-controlled study 16 male healthy volunteers were examined␣with positron emission tomography (PET) with [¹¹C]harmine. Eight of the volunteers were given daily doses of 800 mg esuprone, four were given bi-daily doses of 300 mg moclobemide, and four volunteers were given placebo tablets. PET was performed before initiation of a 7-day treatment period. On day 7, one investigation was made immediately before administration of the drug, representing 23 h after the previous day's treatment for esuprone and 11 h after the last tablets of moclobemide. Further investigations were made 4 h and 8 h after the morning dose on day 7. Results: PET showed a high degree of binding of [¹¹C]harmine, a high-affinity ligand for MAO-A, before the start of treatment, and a marked and similar reduction after treatment with esuprone and moclobemide. A slight tendency for normalisation of enzyme binding was observed at the last time point. In the placebo group no change was observed. Plasma kinetics of esuprone showed a rapid elimination with a half-life of about 4 h. Conclusion: The study demonstrates that esuprone was comparable to moclobemide in its effect on MAO-A inhibition in the brain at the doses given. This is an illustration of the potential of PET to monitor drug effects directly on target biochemical systems in the brain in human volunteers, and the possibility of using these data, rather than pharmacokinetic data, for the determination of dosing intervals. Received: 21 August 1996 / Accepted in revised form: 22 November 1996     

肺系疾病从脾胃论治的探讨

本文论述与肺与脾胃在生理，病理诸方面的密切关系；提出了肺系疾病从脾胃治疗的必要性和重要性；讨论了肺病从脾胃论治之常用７法：即健脾化痰法，芳香醒脾法，健脾利水法，通腑降气法，健脾补肺法，养胃益肺法，补益脾肾法等，对肺系疾病的临床治疗有一定的启发作用和应用价值。     

Sulphhydryl-modifying Reagents Alter Ototoxin Block of Muscarinic Receptor-linked Phosphoinositide Turnover in the Cochlea

In the 12-day-old rat cochlea, the synthesis of inositol phosphates (IPs) can be activated via M3 cholinoceptors. This stimulation is blocked by ototoxins (mercury, ethacrynate, cisplatin, neomycin), drugs with side effects that lead to damage of hair cells and strial cells. As these toxic effects can be reversed in vivo by thiol molecules, we investigated whether modifications of thiol compounds could be involved in ototoxin-induced inhibition of the IP turnover in the cochlea. For this purpose, we assessed whether the sulphhydryl-modifying reagents N -ethylmaleimide and cadmium modify the carbachol-stimulated formation of IPs in the 12-day-old rat cochlea. Both molecules inhibit the carbachol effect on a dose-dependent way without altering the basal metabolism of IPs. As cadmium may block some calcium channels, the effect of verapamil, another calcium channel antagonist, was tested. Verapamil (1 –50 μM) does not alter carbachol-evoked IP formation, suggesting that the inhibitory effect of cadmium is not due to a calcium influx block. Binding experiments with the muscarinic ligand quinuclidinyl benzylate (QNB) showed that the sulphhydryl-modifying reagents do not displace QNB from binding sites. Combining ototoxins and reagents shows that N -ethylmaleimide acts synergistically with all ototoxins but ethacrynate while cadmium does so only with mercury. Both N -ethylmaleimide and cadmium have additive effects with ethacrynate. As a supplement, disulphide bond-modifying agents do not alter the carbachol-enhanced metabolism of IPs. These results suggest that molecules having thiol-modifying properties inhibit the carbachol-induced turnover of IPs without acting at the muscarinic sites. Since thiol modifiers and ethacrynate share similar features in both QNB binding and IP response it is hypothesized that they strike common targets, possibly G proteins.     

Synthesis and Evaluation of Azole-Substituted Tetrahydronaphthalenes as Inhibitors of P450 arom,P450 17, and P450 TxA2

In search of potential drugs for the treatment of estrogen- and androgen-dependent cancer as well as the prophylaxis of metastases, tetralones, tetralins, and dihydronaphthalenes bearing a OCH₃ substituent at the benzene nucleus and an imidazol-4-yl, imidazol-1-yl, or 1,2,4-triazol-1-yl substituent in 2-position were synthesized with and without C₁-spacer between the rings (compounds 2 – 26 ). The compounds were tested in vitro for inhibition of the three target enzymes P450 arom (human placental microsomes), P450 17 (rat testicular microsomes), and P450 TxA₂ (citrated human whole blood). To examine selectivity, some compounds were further tested in vitro for inhibition of P450 18 (bovine adrenal mitochondria), P450 see (bovine adrenal mitochondria) and corticoid formation (aldosterone, corticosterone; ACTH stimulated rat adrenal tissue). In vivo, selected compounds were examined in Sprague Dawley rats regarding P450 TxA₂ inhibition, reduction of plasma testosterone concentration, antiuterotrophic activity (inhibition of the uterotrophic activity of androstenedione), reduction of plasma estradiol concentration (pregnant mares' serum gonadotropin-primed rats), and mammary tumor inhibiting activity (dimethylbenzanthracene-induced tumor; pre- and postmenopausal model). In the series of imidazol-4-yl compounds, which represent a novelty in the field of azole inhibitors of steroidogenic P450 enzymes, strong inhibitors of P450 arom and/or P450 17 were found: 7-OCH₃-2-(imidazol-4-ylmethylene)-1-tetralone ( 4 ) and 7-OCH₃-2-(imidazol-4-ylmethyl)-tetralin ( 12 ) are among the most potent inhibitors of P450 arom in vitro known so far. Compound 4 is a selective inhibitor, whereas 12 shows in addition strong inhibition of P450 17. In contrast to 12 , the 6-OCH₃ derivative (compound 11 ) is a selective inhibitor of P450 17, being 50 times more potent than ketoconazole. Some imidazol-1-yl compounds show a marked inhibition of P450 TxA₂: 2-(imidazol-1-ylmethyl)-1-tetralone ( 13 ) is a selective inhibitor of P450 TxA₂, whereas 7-OCH₃-2-(imidazol-1-ylmethyl)-tetralin ( 17 ) as well as 2-(imidazol-1-ylmethyl)-tetralin ( 16 ) and 7-OCH₃-2-imidazol-1-yl-3,4-dihydronaphthalene ( 25 ) additionally show strong inhibition of P450 arom and P450 17. Regarding the other steroidogenic P450 enzymes as well as corticosterone formation, the compounds show only little inhibitory activity. Aldosterone formation, however, is inhibited at low concentrations. Nevertheless, 4 and 12 are more selective, i.e. inhibit aldosterone synthesis less than the well known inhibitor of P450 arom fadrozole. The compounds show activity in the aforementioned in vivo tests.     

Therapeutic traditions in type 2 diabetes — are they changing?

The utilisation of antidiabetic drugs reflects both the prevalence of diabetes and the different therapeutic traditions of physicians. A questionnaire survey to study attitudes to the use of oral antidiabetic drugs amongst physicians and possible changes in treatment habits was carried out in a representative sample of Finnish physicians (n=454) in 1992 and the results were compared with those of a similar survey carried out in 1985, and with drug utilisation statistics.The mean fasting blood glucose level at which a physician would start pharmacological treatment was 8.7 mmol·l^–1, which was significantly lower than in the 1985 survey. The responses to various case histories suggested a more active approach to pharmacological treatment compared to the 1985 survey. Insulin treatment especially seems to have gained in popularity. This change in attitude was paralled by an increase in the consumption of antidiabetic drugs in Finland during the observation period. The increase in use of oral drugs was steeper in Finland than in Norway and Sweden.Whether this active approach will improve the metabolic control and prognosis of patients with Type 2 diabetes, remains to be demonstrated.     

Involvement of synthesis of brain cell structural proteins in the action of antitheines on long-term memory

Academician S. V. Anichkov Department of Pharmacology, Research Institute of Experimental Medicine, Academy of Medical Sciences, St. Petersburg. (Presented by Academician of the Academy of Medical Sciences A. N. Klimov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 113, No. 5, pp. 506–508, May, 1992.     

解毒保肾汤治疗早期糖尿病性肾病

[目的 ]观察解毒保肾汤治疗早期糖尿病性肾病的疗效 .[方法 ]将诊断为早期糖尿病性肾病的病人随机分为 2组 ,其中治疗组 4 4例给予解毒保肾汤 ,对照组 2 0例给予阳性对照药络汀新 ,观察治疗前后 2组病人的临床症状、空腹血糖、糖化血红蛋白量及尿蛋白排泄率等的变化 .[结果 ]治疗组总有效率为 80 % ,对照组总有效率为 6 5 % ,治疗组疗效优于对照组 ;治疗组在改善临床症状 ,降低空腹血糖、糖化血红蛋白量及尿蛋白排泄率等方面均优于对照组 .[结论 ]解毒保肾汤能够降低早期糖尿病性肾病患者的血糖、减少尿蛋白的排泄 ,具有一定的保护肾脏功能 ,对早期糖尿病性肾病有治疗作用 .     

乌梅及其六种伪劣品的鉴别

乌梅中医临床内服外用均有奇效,但常被杏、山杏、山李、桃、陈乌梅、诃子等伪劣品所混淆,从来源鉴别、性状鉴别、显微鉴别、理化鉴别四方面可将它们相互鉴别区分开来。