Composite phaeochromocytomas-a systematic review of published literature.

INTRODUCTION: Composite phaeochromocytoma is a tumour containing a separate tumour of neuronal origin in addition to a chromaffin cell tumour. This study reports on two cases from a single centre's records and presents a systematic literature review of composite phaeochromocytomas. METHODS: In addition to describing 2 case reports, a systematic search of the Medline database from inception up to April 2020 was done for human case reports on composite phaeochromocytomas. Relevant titles and/or abstracts were screened, and full texts were reviewed to identify appropriate studies. Data was extracted and a descriptive analysis of presentation, clinical features, management strategies and outcomes was performed. The quality of included studies was assessed using a critical appraisal checklist. RESULTS: There were 62 studies included, with a total of 94 patients. Of 91 patients where data was available, the median (range) age of patients was 48 (4-86) years. Of 90 patients where information was provided, 57% were female. In at least 28% of patients, a genetic cause was identified. Common presenting features include abdominal pain, palpable mass, cardiovascular and gastrointestinal symptoms. The most common tumour component with phaeochromocytoma is ganglioneuroma; other components include ganglioneuroblastoma, neuroblastoma and malignant peripheral nerve sheath tumours. In patients with follow-up data (n=48), 85% of patients were alive and well at a median (range) follow-up time of 18 (0.5-168) months. CONCLUSION: Composite phaeochromocytoma is a rare tumour, with a significant genetic predisposition. This review summarises available epidemiological data, which will be useful for clinicians managing this rare condition.

Preventive effects of vanillic acid on lipids, bax, bcl-2 and myocardial infarct size on isoproterenol-induced myocardial infarcted rats: a biochemical and in vitro study.

We made an attempt to evaluate the preventive effects of vanillic acid on isoproterenol-induced myocardial infarcted rats. Rats were pretreated with vanillic acid (5 and 10 mg/kg) daily for 10 days. After pretreatment, rats were injected with isoproterenol (100 mg/kg) at an interval of 24 h for 2 days to induce myocardial infarction. Isoproterenol induction increased the activity of serum creatine kinase-MB and increased the levels of serum and heart cholesterol, triglycerides, free fatty acids in rats. It increased the levels of serum low density and very low density lipoprotein cholesterol and decreased the levels of high-density lipoprotein cholesterol. Also, the activity of 3-hydroxy-3methyl glutaryl-coenzyme-A-reductase in the plasma and liver was increased, and lecithin cholesterol acyl transferase activity in the plasma and liver was decreased in isoproterenol-induced rats. Furthermore, isoproterenol-induced rats showed a decrease in myocardial expression of B-cell leukemia/lymphoma-2(bcl-2) gene and an increase in myocardial expression of bcl-2 associated-x (bax)-gene. Vanillic acid pretreated isoproterenol-induced rats positively altered all the above-mentioned biochemical parameters. Vanillic acid pretreatment also reduced myocardial infarct size in myocardial infarcted rats. In vitro study confirmed the potent free radical scavenging effect of vanillic acid. The observed effects are due to free radical scavenging effects of vanillic acid. This study may have a significant impact on myocardial infarcted patients.

Inhibition of isolated human myometrium contractility by minoxidil and reversal by glibenclamide.

This study investigated the ability of the antihypertensive drug minoxidil to inhibit potassium chloride (KCl)-induced contractility of the isolated human myometrium. Twelve strips of myometrium obtained from 12 patients who underwent hysterectomy were triggered to contract with 55 mM KCl before and after incubation with 3 concentrations (1, 3 and 10 microM) of minoxidil. The percent inhibition by minoxidil on the extent of contraction, and the area under the contractile curve of KCl-induced contraction of the myometrial strips was determined. Furthermore, the effect of 10 microM glibenclamide on the inhibition generated by 3 microM minoxidil on KCl-induced contractility was studied. It was found that minoxidil produced a concentration-dependent inhibition of KCl-induced contractility of the myometrium and that glibenclamide reversed this inhibitory effect. These results suggest that the inhibitory effect of minoxidil on isolated human myometrium contractility may prove useful in clinical conditions requiring relaxation of the myometrium.

Inhibitory effect of anticholinergics on the contraction of isolated caprine urinary bladder detrusor muscle.

This study investigated whether four anticholinergics which are not clinically used for relaxing the urinary bladder detrusor muscle inhibit the contraction of isolated caprine (goat) detrusor muscle: cyclopentolate (100 nm), homatropine (5 microm), ipratropium (500 nm) and valethamate (1 microm). The effects of these anticholinergics were compared with tolterodine (3 microm), an anticholinergic clinically used for relaxing the detrusor muscle. The inhibitory effect of each of these five anticholinergics was studied on six strips of caprine detrusor muscle made to contract with 100 mum acetylcholine (ACh) by determining the percent inhibition of height of contraction and the area under the contractile curve (AUC). It was found that all five anticholinergics inhibited the ACh-induced contraction of the caprine detrusor and that this inhibition was reversed by raising the concentration of ACh. Hence, these four anticholinergics, like tolterodine, may be useful in managing clinical conditions that require relaxation of the detrusor muscle.