A study of serum magnesium levels in acute myocardial infarction and its association with clinical outcome

Background: Cardiovascular disease is one of the leading causes of mortality, morbidity, and increased health-care cost. Magnesium has been implicated in the pathogenesis of acute myocardial infarction (AMI) and its complications. Magnesium ions are considered essential for the maintenance of functional integrity of myocardium. The serum magnesium concentration was found to have great significance in AMI. The present study was undertaken to evaluate the prognostic value of serum magnesium in AMI. Aim and Objectives: The aim of the study was (1) to evaluate serum magnesium levels in patients of AMI on 1st and 7th day post-myocardial infarction and (2) to evaluate validity of serum magnesium as prognostic indicator of Ami. Materials and Methods: This observational cross-sectional study was conducted in the Medicine Department, Guru Nanak Dev Hospital attached to Govt. Medical College, Amritsar. A total of 40 patients of AMI were enrolled in this study. Serum magnesium levels were done for all the patients and its correlation with clinical outcome was observed. Results: On day 1, mean serum magnesium levels in patients with ST-segment elevation myocardial infarction were 1.638 ± 0.19 whereas mean serum magnesium levels in patients with Non-ST-segment elevation myocardial infarction were 2.315 ± 0.321. Mean serum magnesium levels in patients with arrhythmias were 1.73 ± 0.35 on day 1 and 2.14 ± 0.25 on day 7 (P < 0.05). Mean serum magnesium levels at day 1 in patients having mortality are 1.452 ± 0.078 as compared to 2.105 ± 0.399 in rest of surviving patients. It was inferred from this study that patients with AMI with low serum magnesium levels are more prone to develop complications such as arrhythmias and death as compared to patients of AMI with normal serum magnesium levels. Conclusion: Magnesium is an underestimated cation and has been implicated in the pathogenesis of AMI and its complications. Patients of AMI with low serum magnesium levels are found to be more prone to develop arrhythmias as compared to those with normal serum magnesium levels. Hence, it can be concluded that measurement of serum magnesium level is of prognostic significance in AMI.

A comparative study for efficacy and safety of low doses of clonidine for hemodynamic stability in patients undergoing laparoscopic cholecystectomy

Background: This randomized prospective double-blind study was designed to evaluate the efficacy and side effects of low doses clonidine for perioperative haemodynamic stability and postoperative recovery.Methods: Patient’s with ASA grade I–II undergoing laparoscopic cholecystectomy were randomized into three groups of 30 patients each. All patients received either normal saline 10 ml (Group I) or 0.8 µg/kg (Group II) or 1 µg/kg (Group III) over duration of 180 seconds, 10 min prior to laryngoscopy and intubation. Anaesthesia was induced with 1% propofol (2 mg/kg) and maintained with nitrous oxide 60% in oxygen and isoflurane. The parameters assessed at various time intervals were heart rate, systolic blood pressure, diastolic blood pressure, mean arterial pressure and sedation score.Results: Both doses of clonidine proved to be effective in perioperative haemodynamic stability. Clonidine 0.8 mcg/kg was as effectve and safer to Clonidine 1 mcg/kg for attenuatíon of the hemodynamíc responses to laparoscopy. There were no significant differences in the parameters of recovery between groups.Conclusions: Significant hemodynamic derangements can occur during laproscopic cholecystectomy at intubation, pneumoperitoneum and extubation. These were effectively attenuated by premedication with 0.8 mcg/kg and 1 mcg/kg of intravenous clonidine. Dose of 1 mcg/kg though found to be effective but produced adverse effects in form of hypotension and bradycardia.

Substance abuse amongst the medical graduate students in a developing country.

Background & objectives: Substance abuse is found worldwide including among students. We carried out this study to estimate the prevalence of substance abuse among medical student studying in a medical college in north India. Methods: Using a validated questionnaire a cross-sectional survey was conducted among 230 undergraduate and postgraduate medical students in a private medical college. Results: The prevalence of substance abuse was 20.43 per cent (47/230) among medical students. An increase in substance abuse was observed in the latter years of medical education. A total of 43 of 47 (91.7%) students using these substances were aware of the ill effects. The most common reasons for substance use were relief from psychological stress (34/47, 72.4%) and occasional celebration (34/47, 72.4%). Of the 47 substance users, 28 (59.6%) made past attempts to quit the substance abuse. Interpretation & conclusions: Nearly one-fifth of medical students abuse at least one substance despite knowing the ill effects with the main predisposing factor being the psychological stress.

A study of cardiovascular effects of Azadirachta indica (neem) on isolated perfused heart preparations.

The effects of aqueous leaf extract of Azadirachta indica were evaluated on isolated prefused frog and rabbit heart. Dose dependent negative inotropic and chronotropic effects were observed in both the heart preparation. An increase in coronary blood flow in isolated rabbit heart was observed. The effects were not blocked by atropine and mepyramine in both the preparations. The data suggests that A. indica could be of benefit in coronary artery disease and arrhythmias.

Differential modulation of nociceptive responses to mu and kappa opioid receptor directed drugs by blood glucose in experimentally induced diabetes rats.

The study has evaluated the effect of diabetes associated hyperglycaemia on nociception and antinociception induced by morphine, buprenorphine and pentazocine in female albino rats. Rats were allocated into 3 groups of 20 each--group I consisted of control having normal blood glucose levels (BGLs), group II consisted of streptozotocin-induced diabetics (STZ-D) having hyperglycaemia and group III consisted of diabetic rats controlled with insulin treatment. Immediately before and 15, 30 min, 1, 2 and 3 hr after injection with test drugs, rats were subjected to a thermal noxious stimulus using tail withdrawal from hot water and tail-flick latencies (TFL) so generated were recorded. Similarly, before and 30, 45 min and 1 hr after injection with drugs rats were subjected to abdominal writhing with hypertonic saline and number of writhes were counted per 90 sec. In STZ-D animals (BGLs 317.95 +/- 3.8 mg/dl) a decreased TFL with an increase in the number of writhes compared to control and diabetes controlled with insulin treatment was observed. Percent maximum possible effect of morphine (5 mg/kg, s.c.) and buprenorphine (2 mg/kg, s.c.) was significantly lower when compared to control as well as STZ-D controlled with insulin treatment groups. Similarly percent protection from writhing of morphine (0.05 mg/kg, s.c.) and buprenorphine (0.01 mg/kg, s.c.) was significantly less in comparison to control and STZ-D controlled with insulin treatment group. However, percent maximum possible effect of pentazocine (20 mg/kg, s.c.) and percent protection from writhing of pentazocine (1 mg/kg, s.c.) was significantly high in STZ-D rats when compared to control and STZ-D rats controlled with insulin treatment groups. The results suggest that both mu and kappa--opioid receptors may be modulated by blood glucose levels possibly involving cellular energetics mediated change in potassium (KATP) channels in females rats, albeit differentially.

A study of hypoglycaemic effects of Azadirachta indica (Neem) in normaland alloxan diabetic rabbits.

Hypoglycaemic effect was observed with Azadirachta indica when given as a leaf extract and seed oil, in normal as well as diabetic rabbits. The effect, however, was more pronounced in diabetic animals in which administration for 4 weeks after alloxan induced diabetes, significantly reduced blood glucose levels. Hypoglycaemic effect was comparable to that of glibenclamide. Pretreatment with A. indica leaf extract or seed oil administration, started 2 weeks prior to alloxan, partially prevented the rise in blood glucose levels as compared to control diabetic animals. The data suggests that A. indica could be of benefit in diabetes mellitus in controlling the blood sugar or may also be helpful in preventing or delaying the onset of the disease.

Effect of Azadirachta indica (Neem) leaf aqueous extract on paracetamol-induced liver damage in rats.

The effect of aqueous leaf extract of Azadirachta indica (A. indica) was evaluated in paracetamol induced hepatotoxicity in rats. Liver necrosis was produced by administering single dose of paracetamol (2 g/kg, p.o.). The liver damage was evidenced by elevated levels of serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma glutamyl transpeptidase (gamma-GT) and by histopathological observations of liver sections. Aqueous A. indica leaf extract (500 mg/kg, p.o.) significantly (P < 0.01) reduced these elevated levels of AST, ALT and gamma-GT. Paracetamol induced liver necrosis was also found to be reduced as observed macroscopically and histologically.

Evaluation of haloperidol, a dopamine antagonist, on intraocular pressure in experimental glaucoma.

Haloperidol, a dopaminergic antagonist, was found to be very effective in lowering intraocular pressure in normal and glaucomatous eyes. The potential ocular hypotensive effect of haloperidol can be utilized for the treatment of glaucoma.

Effect of Trigonella foenum graecum (Fenugreek) on blood glucose in normal and diabetic rats.

Trigonella foenum graecum (Fenugreek) was administered at 2 and 8 g/kg dose orally to normal and alloxan induced diabetic rats. It produced a significant fall (P < 0.05) in blood glucose both in the normal as well as diabetic rats and the hypoglycemic effect was dose related.

Experimental inhibition of proliferative vitreoretinopathy in retinal detachment using daunorubicin.

Proliferative vitreoretinopathy (PVR) remains the most common cause of failure in retinal detachment surgery. Surgical procedures for its repair entails complex and extensive instrumentation besides technical skill. The success rate varies widely with high incidence of redetachment. Keeping this in view, we evaluated the role of intravitreal daunorubicin as an anti-mitiotic agent in the inhibition of PVR. Our study concluded that 5 micrograms of intravitreal daunorubicin effectively inhibited PVR in the rabbit eye and the dosage was safe and nontoxic. The half-life of the drug was determined to be about 140 minutes, suggesting a prolonged intravitreal concentration sufficient to prevent fibroblast proliferation.

Metabolic factors in the development of retinopathy of juvenile-onset type I diabetes mellitus.

Thirty-five patients of insulin-dependent diabetes mellitus (IDDM) were investigated for the effect of various metabolic factors on retinopathy. The severity of retinopathy increased with duration and age of onset of IDDM. Degree of glycaemia (fasting blood sugar, FBS) was similar in patients with or without retinopathy. All IDDM patients as a group showed severe carbohydrate intolerance with lower basal and post glucose serum immunoreactive insulin (IRI) levels and serum C-peptide radioimmunoreactivity (CPR) as compared to controls. The insulin secretory response was similar in no retinopathy, mild retinopathy and severe retinopathy groups. Patients with retinopathy had higher incidence of hyperlipidemia but mean serum levels of cholesterol and triglyceride were similar. This study does not suggest a direct relationship between the various metabolic factors studied and retinopathy due to IDDM.

Effects of ranitidine alone and in combination with chlorpheniramine on histamine-induced wheal and flare and psychomotor performance.

Some reports suggest that addition of an H2 antagonist increases the efficacy of H1 antagonist but the influence on the side effect profile of antihistamines are largely unknown. The effects of ranitidine, chlorpheniramine, their combination and placebo on histamine induced wheal and flare, psychomotor performance and subjective symptoms were studied in 6 healthy male volunteers in a double blind randomized and cross-over (Latin square) study. Ranitidine significantly reduced the histamine induced wheal at 4 hrs (P < 0.05). Chlorpheniramine and the combination significantly reduced both histamine induced wheal and flare at 2 hrs and at 4 hrs (P < 0.05). Addition of ranitidine reduced the feeling of sleepiness produced by chlorpheniramine, though other subjective symptoms were not affected. None of the treatment schedules produced any consistent change in the psychomotor performance of the volunteers.

Background noise in healthy volunteers--a consideration in adverse drug reaction studies.

In adverse drug reaction studies proper control over 'Back ground noise' is to be maintained to avoid erroneous conclusions to be drawn for adverse drug effects. Healthy volunteers, not taking any medication, were surveyed by a questionnaire to obtain data on the occurrence of any symptoms, often ascribed to side effects of drugs. Only 62 subjects out of a total of 236 (26.27%) stated experiencing none of these symptoms during the previous 3 days. The remaining subjects reported some symptoms, with an median number of symptoms experienced per person being 2; the most common being fatigue; headache, inability to concentrate and excessive sleepiness.

Anti-insulin antibodies and retinopathy in juvenile onset type-1 diabetes.

Juvenile diabetics have severe loss of beta cell function and require replacement therapy with insulin. Insulin antigenicity can produce anti-insulin antibodies resulting in allergic reactions and insulin resistance. The role of insulin-anti-insulin antibody complexes in the development and progress of chronic diabetic complications like microangiopathy is not very clear. In the present study, there was statistically a significant trend of higher insulin antibody binding levels in IDDM patients who developed retinopathy. Though there was a trend of higher insulin antibody in IDDM patients with retinopathy, there was no association between insulin antibody and HLA antigen which some authors have reported.

Effect of fatty diet on pharmacokinetics and pharmacodynamics of a liquid theophylline preparation in volunteers.

The effect of a standard breakfast and a fatty breakfast on the pharmacokinetics and pharmacodynamics of a theophylline liquid preparation (160 mg-single dose) was examined in 6 healthy, non-smoking male volunteers. The plasma theophylline concentrations after both standard and fatty diet were found to be comparable at each point of time and pharmacokinetic parameters like Cmax, Tmax, T1/2a, T1/2 beta and AUC0-alpha, were also comparable. However, the time taken to attain the therapeutic plasma concentration was earlier and sustained along with the standard breakfast in comparison to that with fatty breakfast. Peak change in PEFR and pulse rate was also observed earlier with the standard diet than with fatty diet. The plasma theophylline concentrations produced after both diets were insufficient to produce any detectable change in subjective symptoms like tremor palpitation, heart burn, nausea, restlessness and tenseness. However, theophylline after fatty breakfast was better tolerated than that after a standard breakfast.

Visual evoked responses in tuberculous children on ethambutol therapy.

Visual evoked responses (VERs) were recorded in 47 children, aged 3-13 years with tuberculosis, treated with ethambutol (20 mg/kg/day) as a part of the antitubercular regimen. VERs were evoked by monocular whole field stimulation, the stimulus being provided by a black and white checker-board pattern reversed every 560 msec and recorded before the commencement, 2, 4, 6, 9 and 12 months of therapy and between 3 to 6 months after stopping the drug. In the first 6 months of therapy the mean values of latency ranged from 92.8 to 101.3 msec in the 3 to less than 6 years age group and 88.5 to 100.3 msec in children 6-13 years of age. Between 6-12 months of therapy the mean values of latency were between 93.3 to 101.0 msec in the 3 to less than 6 years age group and 96.0 to 101.5 msec in the older group. Between 3-6 months after stopping therapy the means of latency ranged from 92 to 96 msec. The differences were not statistically significant at any point of time. Thus, children do not seem to be at greater risk for developing ethambutol inducted optic damage as compared to adults. Ethambutol in the above stated dose may, therefore, be recommended for inclusion in antitubercular chemotherapy in pediatrics without undue fear of subclinical toxicity.