Oxidative stress in patients with essential hypertension.

BACKGROUND: Free oxygen radicals react with membrane lipids to form lipid hydroperoxides, a destructive process known as lipid peroxidation. Lipid hydroperoxides decompose to form a variety of products including malondialdehyde, which is used as an indicator of the oxidative damage of cells and tissues. Endogenous antioxidant enzymes such as superoxide dismutase counteract the oxidative damage from oxidative stress. There is increasing evidence that free radicals are involved in the pathogenesis of hypertension by altering endothelial function. We evaluated the oxidative stress and endogenous enzymatic antioxidant status in patients with essential hypertension before and 3 months after treatment with antihypertensives. METHODS: Fifty patients with essential hypertension attending the outpatient services of the Department of Medicine, Institute of Medical Sciences, Banaras Hindu University and 20 age- and sex-matched healthy controls were studied. The serum malondialdehyde and superoxide dismutase levels were measured in patients at the time of presentation and after 3 months of antihypertensive treatment. No antioxidants were given to the patients during the period of the study. RESULTS: The mean (SD) serum malondialdehyde level was found to be significantly higher (0.33 [0.07] mmol/L) in patients with hypertension compared with controls (0.21 [0.05] mmol/L; p < 0.001). This showed a significant decrease following antihypertensive therapy (0.23 [0.06] mmol/L; p < 0.001) compared with pre-treatment values. The serum superoxide dismutase activity was significantly lower in patients (6.93 [1.35] mg protein/ml of serum) compared with controls (20.12 [3.65] mg protein/ml serum; p < 0.001) at the time of presentation and, compared with the pre-treatment values, increased significantly after 3 months of treatment (10.66 [2.91] mg protein/ml of serum; p < 0.001). CONCLUSION: Our study shows that essential hypertension is associated with increased oxidative stress and reduced antioxidant status. Adequate control of blood pressure with antihypertensive therapy decreases oxidative stress and improves the antioxidant status in these patients.

Efficacy of a home-made spacer with acute exacerbation of bronchial asthma: a randomized controlled trial.

Metered dose inhaler (MDI) with spacer is the preferred method for administration of aerosolized medications in pediatric asthma. The expense of commercial spacers limits their use and indigenous alternatives have therefore been developed. Information on the clinical efficacy of home-made spacers is limited. This study was conducted to compare the efficacy of a valve-less home-made spacer with a commercial spacer in delivering salbutamol via MDI in acute asthma. Asthmatic children aged 5-15 years who presented with an acute exacerbation to the pediatric chest clinic of a tertiary care hospital were enrolled in a single blinded randomized parallel group study. The study patients received 10 puffs of salbutamol (100 microg/puff) via MDI-home-made spacer or MDI-commercial spacer. Pre and post inhalation measurements of peak expiratory flow rate (PEFR), oxygen saturation (SaO2), respiratory rate (RR), pulse rate (PR) were made and compared. Sixty children were enrolled in the study, 31 were administered salbutamol via the home-made spacer and 29 via the commercial spacer. The median increase in PEFR was similar in both the groups (20.8% vs 22.2%, p=0.4), clinical improvement being satisfactory in all patients. The valve-less home-made spacer is equally efficacious and cheaper than the commercial spacer in administering bronchodilators in acute exacerbations of asthma. Further studies on the efficacy of home-made spacer in delivery of inhaled steroids are needed.

Bioactivity of marine organisms: Part VIII--Screening of some marine flora of western coast of India.

Methanolic extracts of 31 botanically identified species of marine flora, collected from Gujarat Coast, have been screened for a wide range of biological activities. Of these, 3 extracts showed anti-implantation, 2 had antiviral, 2 showed hypotensive, 1 had anti-inflammatory while 12 extracts showed diuretic activities. The antiviral activity; against EMCV, was confirmed in one alga. The active principles and results of these studies are reported.

Effects of oral lithium on the action of various C.N.S. active drugs.

Effects of prolonged lithium administration was seen on the action of various psychoactive drugs in animals. Apomorphine induced pecking in pigeons increased significantly by lithium treatment for 14 days, from 1445.3 +/- 202.5 in control to 2785.8 +/- 205.8 in Gp. B. Haloperidol-induced catalepsy score in albino rats increased significantly following chronic lithium treatment compared to control. Chlorpromazine-induced hypothermia in rabbits was immediate but transient, while in lithium treated rabbits induction of hypothermia was delayed, sustained and of greater magnitude. This action of lithium may be mediated by increasing the permeability of blood-brain barrier, or enhancing the sensitivity of alpha-adrenoceptors in brain.

Effect of oral zinc supplementation on copper and haemoglobin levels in pregnant women.

In the present study, pregnant women in different trimesters of pregnancy were randomly allocated to untreated control group (Gp A; n = 58), and zinc treated group (Gp B; n = 104). Both groups were administered ferrous sulphate 60 mg, and folic acid 5 mg, twice daily throughout the period of study. Gp B subjects were also administered 45 mg elemental zinc, in a single daily post lunch dose. Maternal blood and urine samples collected in each trimester, and at the time of delivery, and blood taken from the umbilical cord were tested for Cu levels. Maternal Hb was also estimated. In Gp A, mean serum Cu increased significantly from 117.15 +/- 2.12 micrograms/dl in I trimester to 138.57 +/- 0.92 micrograms/dl in III trimester (P < 0.001). In Gp B, serum Cu declined significantly from 115.64 +/- 1.12 micrograms/dl in I trimester to 111.10 +/- 0.99 micrograms/dl in III trimester (P < 0.001). Urinary Cu declined significantly from 47.24 +/- 2.31 micrograms/24 hrs in I trimester to 37.43 +/- 2.06 micrograms/24 hrs in III trimester (P < 0.01). Zn treatment did not alter differentially the serum Cu levels in anaemic and normohaemic subjects. Gp B cord blood serum Cu was significantly lower as compared to respective controls, significance being proportional to duration of zinc administration. Hb levels increased significantly in all subjects. Increase in Hb in Gp B was significantly higher in comparison to that in Gp A (P < 0.05). Elemental zinc when administered to pregnant women in a dose of 20-45 mg/day, causes improvement in Hb level, without leading to hypocupremia.

Zinc taste test in pregnant women and its correlation with serum zinc level.

Pregnant women in different trimesters of pregnancy were divided into control (n = 58) and study (n = 104) groups. Study group subjects were given 45 mg zinc/p.o./day as 200 mg 'zinc sulphate tablets from the day of reporting till term. Body zinc status was clinically assessed by 'zinc taste test'. Blood samples were drawn at the same time and serum zinc levels measured. Zinc taste test scores decreased with advancement of pregnancy (P < 0.05) and increased significantly following zinc administration (P < 0.05). Serum zinc level declined significantly with advancement of pregnancy (P < 0.001). Following zinc administration, serum zinc level increased significantly (P < 0.001). Accuracy of zinc taste test in individual cases ranged between 70 and 100 percent. On the whole, zinc taste test was well correlated with serum zinc level, and provides a fair idea of zinc deficiency.

A study of the effect of oral zinc supplementation during pregnancy on pregnancy outcome.

Women in different trimesters of pregnancy (Group B; n = 106) were administered 200 mg zinc sulphate (elemental Zn 45 mg) orally/day from the day of reporting till delivery. Untreated group of 62 served as control. Levels of zinc in maternal serum, umbilical cord blood serum, and urine were estimated. Pregnancy outcome was assessed in terms of incidence of prematurity, IUGR, birth weight; apgar score and gestational age. Serum zinc levels in Gp. A declined significantly from 113.00 +/- 2.80 ug/dl in I trimester to 83.78 +/- 2.20 ug/dl in III (P < 0.001). Following zinc supplementation (Gp. B) serum zinc levels increased significantly from 109.70 + 3.23 micrograms/dl to 205.40 +/- 4.47 micrograms/dl (P < 0.001). Urinary excretion of zinc in Gp. A declined significantly with increase in the period of gestation. However in Gp. B, elimination of Zn increased significantly in proportion with the serum levels (P < 0.001) cord blood serum zinc level was normal irrespective of maternal serum Zn levels. Following oral Zn supplementation, levels increased significantly from below 127.0 micrograms/dl to above 158.0 micrograms/dl in Gp. B (P < 0.001). Maternal serum and cord blood serum zinc ratios were fairly constant in Gp. A as well as in Gp. B. Birth weight of babies born with Zn supplementation was significantly higher than control and was related to duration of oral zinc supplementation (P < 0.001). Gestational age of babies in Gp. B was significantly higher than respective controls when Zn supplementation was given for more than 3 months (P < 0.01), and was related to duration of zinc therapy (P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Bioactivity of marine organisms: Part VI--Screening of some marine flora from Indian coasts.

Alcoholic extracts of 50 botanically identified species of marine flora have been screened for a wide range of biological activities. Of these, 2 extracts exhibited anti-amoebic and antiviral activity each, 3 of them had anti-implantation activity; 9 had hypoglycaemic activity while hypotensive activity was associated with 11 extracts; 14 extracts were found to be diuretic and 1 of them had anti-inflammatory activity. Further, 10 of these extracts exhibited 2 types of activities while a combination of 3 and 4 types of activities was observed in one extract each. Follow-up studies have been carried out in some plants with confirmed activity. The active principles and results of these studies are reported.