Interaction of aristolochic acid with Vipera russelli phospholipase A2: its effect on enzymatic and pathological activities

Aristolochic acid, an alkaloid from the plant Aristolochia species, interacts with the major basic phospholipase A2 from Vipera russelli venom. It is an uncompetitive inhibitor with a Ki of 9.9 X 10(-4)M when phosphatidylcholine is used as substrate. The inhibition of direct and indirect hemolysis is higher compared to the inhibition of phosphatidylcholine hydrolysis. Edema-inducing activity of Vipera russelli phospholipase A2 is inhibited by aristolochic acid when injected either as a mixture or separately. Both i.m. and i.p. administration of aristolochic acid following phospholipase injection are equally effective in inhibiting edema. The alkaloid inhibits the edema-inducing activity as soon as it reaches the site, but does not aid in recovery. Aristolochic acid failed to inhibit other pathological activities of the enzyme.     

Standards of care for area mental health services

A provisional set of standards of care was derived from a quality assurance strand of a wider research project, which reported the development of evaluation strategies for area integrated mental health services (AIMHS). In contrast to most published standards, they apply to all facets of care in a comprehensive catchment area mental health service, whether clinical or functional, community or hospital based, urban or rural, or managed by the public, private or voluntary sectors. We review briefly existing sets of standards of mental health services and report the process of development of standards of care, each with sub-sets of performance indicators and examples. While the AIMHS standards and a companion quality assurance manual are still undergoing refinement, they offer a guide for mental health professionals to the provision of services, and a checklist to service-users of services that should be available to them at every stage of care in a mental health system.     

Trial of ketotifen in childhood asthma

An open trial of Ketotifen was conducted on 29 children suffering from asthma of varying duration. The drug was given orally in a dose of 1 mg twice a day. Children were followed up weekly for a period of 3 months. It was found beneficial (though the benefit was not statistically significant) in children having asthma of less than 2 years duration who were taking one drug regularly or were on occasional treatment. There was marginal effect in children taking salbutamol and theophylline together, but irregularly and no benefit in children taking prednisolone.     

Purification of a soluble tetrodotoxin-sensitive protein from the cytoplasmic fraction of bovine brain tissue

Highly purified protein inducing tetrodotoxin-dependent Na fluxes in liposomal membrane was obtained from the cytoplasmic fraction of the bovine brain. The protein was purified by anion-exchange chromatography on DEAE-Servacell and wheat germ agglutinin sepharose (WGA) followed by gel filtration on sepharose 4B. It is a high-molecular weight acidic glycoprotein; during denaturation under reducing conditions it forms 55 kD subunits. It is suggested that the tetrodotoxin-sensitive protein could be a soluble intracellular precursor of the voltage-dependent sodium channels.     

Peripheral circulatory changes in patients in the acute period of transmural myocardial infarct

Altogether 107 patients with transmural myocardial infarction were investigated by determination over time the volumetric blood flow rate in the forearm using a plethysmograph with mercury-rubber gages and A-V oxyhemoglobin difference. With relation to a degree of expression of acute heart failure all the patients were divided into 4 groups. Considerable volumetric peripheral blood flow rate changes were noted in the acute phase of transmural myocardial infarction. A degree of a decrease in the rate well correlated with expression of clinical signs of heart failure. Indices of A-V oxyhemoglobin difference also showed correlation with expression of acute heart failure growing with its increase. The combined determination of these indices, probably reflecting 2 tendencies (blood flow decrease and centralization), is of certain prognostic value.     

Transurethral resection of the prostate and metastatic prostate cancer

Demonstration of malignant cells in blood specimens collected during transurethral resection of the prostate (TURP) has implicated TURP in the dissemination of prostatic cancer. Of 153 patients who underwent radiation therapy for prostate cancer between January 1977 and June 1990 and were retrospectively analyzed, 93 were evaluable. Fifty-nine patients required TURP before radiation therapy for prostatic obstruction (BPH and/or cancer); the remaining 34 patients underwent radiation therapy after fine-needle aspiration biopsy. No statistically significant difference in failure rate could be detected between these groups, with a failure rate of 47% (28 of 59 patients) at a median follow-up time of 49 months (range, 8 to 146 months) in the TURP group versus a failure rate of 47% (16 of 34 patients) at a median follow-up time of 50 months (range, 3 to 122 months) in the group who underwent biopsy only (Fisher's exact test, P = 0.23). Within the confines of this retrospective study, it appeared that TURP did not enhance the development of metastatic disease.     

Transluminal angioplasty of the vertebral and basilar artery

Transluminal angioplasty of brachiocephalic vessels for atherosclerotic lesions is now being performed in selected cases. We have thus far treated 17 cases of vertebral artery stenosis and one case of basilar artery stenosis by intravascular balloon dilatation techniques. Clinical presenting symptoms included vertebral basilar insufficiency, repeated transient ischemic attacks (TIAs), and multiple strokes. We performed successful transluminal angioplasty in 16 patients with marked narrowing (greater than 70%) of the dominant vertebral artery from atherosclerosis. One patient with basilar artery stenosis with tandem atherosclerotic lesions was also treated by angioplasty techniques. Repeat angiography at 3- to 12-month intervals has revealed continued patency at the angioplasty site. Complications occurred in our one patient with basilar artery angioplasty, who suffered a brainstem infarction after treatment, and in one patient who had a TIA after bilateral vertebral artery angioplasty. Two other patients had residual vertebral stenosis but remained asymptomatic after the procedure. All other patients who had successful dilatation were asymptomatic at 6 months to 2 years (mean, 15 months) of follow-up. These initial studies indicate that vertebral artery angioplasty may be effective for treating high-grade atherosclerotic lesions and for improving blood flow to the posterior circulation. Angioplasty of the basilar artery is technically more difficult and has a higher degree of risk because of the many perforating branches supplying the brainstem.