Effect of ascorbic acid on long-term cold exposure induced changes in thyroid activity in Sprague Dawley rats.

OBJECTIVE: To determine the effect of ascorbic acid supplementation on long-term cold exposure induced changes in thyroid activity in Sprague-Dawley rats. STUDY DESIGN: Experimental study. PLACE AND DURATION OF STUDY: Physiology Department of Islamic International Medical College, Rawalpindi, National Institute of Health, Islamabad and Railway Hospital, Rawalpindi, from January to December 2009. METHODOLOGY: Ninety Sprague-Dawley rats were randomly divided into three groups of control, cold exposed and cold exposed along with ascorbic acid supplementation. After one month, their thyroid levels were analyzed by using chemiluminescent immunometric assay on Siemens Immulite 2000 Analyzer. RESULTS: After 4 weeks of cold exposure to experimental animals, the thyroid activity was raised significantly in the cold exposed group as compared to the control group (p-value for T3 difference = 0.004, T4 difference = 0.002 and TSH difference < 0.001). Supplementation with ascorbic acid in the third group normalized the thyroid hormone activity with p-value for difference in levels of T3 being 0.6661, T4 = 0.027 and TSH = 0.0028. CONCLUSION: Ascorbic acid prevented the cold induced changes in thyroid hormone levels in rodents.

Offspring sex ratios among male tobacco smokers in Khartoum, Sudan.

OBJECTIVES: To explore any association between paternal tobacco smoking and the offspring secondary sex ratio, as well as the effect of duration and intensity of smoking on gender ratio. METHODS: The cross-sectional study was conducted around major public areas within Khartoum, Sudan, between August and September 2008 and involved 458 married Sudanese males with offsprings. The sample consisted of 111 (24.2%) smokers and 347 (75.8%) non-smokers who were evaluated using a questionnaire on their offspring gender. Data on duration and intensity of smoking was also collected from the smokers' group. SPSS 16 was used for statistical purposes. Chi-square test was used to test for significance of associations between variables. Analysis of variance (ANOVA) was used to test for significance between ratios. RESULTS: The number of cigarettes smoked in males increases the likelihood of having a male offspring. The gender ratio in non-smokers was 1.11, while it was 1.15 in smokers. CONCLUSION: Paternal smoking increases the offspring sex ratio.

Protective role of ginger on lead induced derangement in plasma testosterone and luteinizing hormone levels of male Sprague Dawley rats.

BACKGROUND: Lead is one of the most serious environmental threats to human health especially in developing countries. It damages multiple body systems including the reproductive system. Ginger's antioxidant and androgenic activity is reported in multiple animal studies. The aim of this study was to investigate the ameliorative effect of Zingiber officinale (ginger) on lead induced derangement in plasma testosterone and luteinizing hormone (LH) levels of male rats. METHODS: Sixty adult male Sprague Dawley rats were used in this study in four groups. Group A served as normal control, Group B received 0.3% lead acetate in drinking water, Group C and group D received supplementary 0.5 and 1 gm/Kg bodyweight of ginger respectively along with lead acetate in drinking water. Five rats from each group were sacrificed at the end of 2nd, 4th and 6th weeks. Serum testosterone and LH levels were analysed using ELISA technique. RESULTS: After co administration with different doses of ginger, serum testosterone level which was significantly decreased in lead treated group, showed a significant rise as compared to lead treated group. LH levels which had exhibited no significant change by lead treatment, after co administration with different doses of ginger, again showed no significant change. CONCLUSION: Oral administration of ginger ameliorated lead induced testicular toxicity in male rats by increasing serum testosterone level at all durations which might be a product of both its androgenic and antioxidant properties.

Effects of simvastatin and alpha-tocopherol on disturbed nerve conduction in obese Sprague Dawley rats.

BACKGROUND: The incidence of obesity is increasing worldwide. The neuropathy associated with obesity, that is evident from disturbed nerve conduction, is one of the complications for which a number of treatment options are being considered. In this study, Simvastatin, a hydroxyl methyl glutaryl coenzyme A reductase inhibitor and alpha-tocopherol, a dietary antioxidant are compared for their effects on sciatic nerve conduction velocity. OBJECTIVES: To compare the effects of Simvastatin and alpha-tocopherol on sciatic nerve conduction velocity in obese rats. METHODS: The study was a Randomised control trial conducted from December 2008 to November 2009. One hundred and twenty adult male Sprague Dawley rats were divided into four groups with 30 rats in each group. One group of rats was taken as control with normal diet while other three groups were given high fat diet (HFD) for the whole study period. Along with the high fat diet, group III and group IV were given Simvastatin and alpha-tocopherol supplemented diet respectively. At the end of study, conduction velocity of sciatic nerve was determined with the help of PowerLab data acquisition system. RESULTS: The three groups with HFD showed more than 25% increase in weight at the end of study compared to control group. The control group with high fat diet (Group II) showed decreased sciatic nerve conduction velocity when compared with control (Group I). Both the groups that were given Simvastatin and alpha-tocopherol each showed improvement in sciatic nerve conduction velocity (p<0.001) after four weeks when compared with the group that was given HFD without any supplementation. However with alpha-tocopherol, the nerve conduction velocity was improved more significantly. CONCLUSIONS: Simvastatin and alpha-tocopherol both are effective for improving sciatic nerve conduction velocity in HFD induced obesity.

Effects of simvastatin on lipid profile and nerve conduction velocity in obese Sprague Dawley rats.

BACKGROUND: The incidence of obesity is increasing worldwide. The lipid derangements and decrease in nerve conduction velocity are important complications for which a number of treatment options are being considered. In this study, Simvastatin, a hydroxyl methyl glutaryl coenzyme A reductase inhibitor is studied for its effects on these complications of obesity. METHODS: The study was a randomised control trial conducted at Islamic International Medical College, Rawalpindi in collaboration with Railway General Hospital, Rawalpindi, and National Institute of Health, Islamabad. Ninety adult male Sprague Dawley rats were divided into three groups with thirty rats in each group. One group of rats was taken as control with normal diet while other two groups were given High Fat Diet (HFD) for the whole study period, i.e., 10 weeks. One of the HFD group was given Simvastatin along with high fat diet for four weeks. Lipid profile was done by enzymatic colorimetric method. Conduction velocity of sciatic nerve was determined with the help of PowerLab data acquisition system. RESULTS: The two groups with HFD showed more than 25% increase in weight at the end of study as compared to control group. HFD group showed significantly higher lipid profile and decreased sciatic nerve conduction velocity when compared with control. The group that was given Simvastatin showed significant improvement in lipid profile and increased sciatic nerve conduction velocity after 4 weeks when compared with the group that was given HFD without any intervention. CONCLUSIONS: Simvastatin is effective for improving the lipid profile and sciatic nerve conduction velocity in HFD induced obesity.

Effect of ascorbic acid on fatigue of skeletal muscle fibres in long-term cold exposed Sprague Dawley rats.

BACKGROUND: On exposure to prolonged cold temperature, the body responds for effective heat production both by shivering and non-shivering thermogenesis. Cold exposure increases the production of reactive oxygen species which influence the sarcoplasmic reticulum Ca++ release from the skeletal muscles and affect their contractile properties. The role of ascorbic acid supplementation on force of contraction during fatigue of cold exposed skeletal muscles was evaluated in this study. METHOD: Ninety healthy, male Sprague Dawley rats were randomly divided into three groups of control (I), cold exposed (II), and cold exposed with ascorbic acid 500 mg/L supplementation mixed in drinking water (III). Group II and III were given cold exposure by keeping their cages in ice-filled tubs for 1 hr/day for one month. After one month, the extensor digitorum longus muscle was dissected out and force of contraction during fatigue in the skeletal muscle fibres was analysed on a computerised data acquisition system. RESULTS: The cold exposed group showed a significant delay in the force of contraction during fatigue of skeletal muscle fibres compared to control group. Group III showed easy fatigability and a better force of contraction than the cold exposed group. CONCLUSIONS: Ascorbic acid increases the force of contraction and decreases resistance to fatigue in the muscles exposed to chronic cold.

Reliability of the neurological scores for assessment of sensorimotor neuropathy in type 2 diabetics.

OBJECTIVE: To check the reliability of the commonly used neurological scoring systems taking the nerve conduction studies as the reference. METHODS: Diagnosed diabetics (n=60) were selected by purposive sampi ng Detection and grading of neuropathy were done according to Diabetic Neuropathy Symptom Score (DrNS), modified Neuropathy Symptom Score (NSS), Diabetic Neuropathy Examination (DNE) and modified Neuropathy Disability Score (NDS). For the nerve conduction studies, amplitudes, velocities and latencies of minimum two (Sural, Peroneal) and maximum six, i.e., three sensory (Sural, Ulnar, Median) and three motor (Peroneal, Ulnar, Tibial) nerves were checked. If the patient had 2 or more than two abnormal findings in any of the nerve he was labeled to have peripheral sensorimotor neuropathy. Later the sensitivity, specificity and diagnostic efficacy of each neurological score was checked taking nerve conduction studies as the gold standard. RESULTS: Taking the NCS as gold standard DNS, DNE, NSS and NDS had 64.1%, 17.95%, 82.05%, 92.31% sensitivity and 80.95%, 100%, 66.67%, 47.62% specificity, respectively. Diagnostic efficacy of DNS was 70%, DNE was 47%, NSS was 77% and NDS was 77%. CONCLUSIONS: Combining different scores gives better sensitivity and specificity. NDS is the most reliable neurological test for detecting and grading DPN.

Short duration head-up tilt test: a comparison with conventional long protocol in patients of orthostatic intolerance.

BACKGROUND: Orthostatic intolerance is development of symptoms during upright standing relieved by recumbency. An individual's predisposition to orthostatic intolerance (development of symptoms during upright posture) can be identified by Head-up Tilt Test (HUT). The aim of the present study was to compare the diagnostic yield (Percentage of patients tested positive) of short duration with conventional HUT. METHODS: The study was conducted in Islamic International Medical College, Rawalpindi in collaboration with Armed Forces Institute of Cardiology/National Institute of Heart Diseases. A total number of 100 patients with orthostatic intolerance were studied. The conventional and short duration HUT protocols were compared. Conventional protocol had a passive tilt phase of 30 minutes and drug provocation phase of 20 minutes while the short duration protocol had both phases of 15 minutes, thereby reducing the test duration by 20 minutes. All patients underwent short duration HUT and patients with positive test were considered positive for conventional HUT as well. Patients having negative short duration HUT underwent conventional HUT after one week. Comparison was done using Chi-square statistics and p < 0.05 was considered significant. RESULTS: Diagnostic yield of short duration and conventional HUT was 53% and 63% respectively with no statistically significant difference between the two protocols (p = 0.15). CONCLUSIONS: Head-up tilt test (HUT) is an effective investigative tool for orthostatic intolerance with satisfactory diagnostic yield. Short duration HUT may be substituted for conventional HUT to save time and to accommodate more patients.

Comparison of nerve conduction studies with diabetic neuropathy symptom score and diabetic neuropathy examination score in type-2 diabetics for detection of sensorimotor polyneuropathy.

OBJECTIVE: To compare the nerve conduction studies in clinically undetectable and detectable sensorimotor polyneuropathy in type 2 diabetics. METHODS: Diagnosed diabetics (n = 60) were divided in two groups. Group 1 (n1 = 30) with clinically undetectable and group 2 (n2 = 30) with clinically detectable Diabetic Polyneuropathy. Detection of the sensorimotor neuropathy was done according to Diabetic Neuropathy Symptom Score and Diabetic Neuropathy Examination scores. The simplified nerve conduction studies protocol was followed in recording amplitudes, velocities and latencies of minimum two (Sural, Peroneal) and maximum six i.e. three sensory (Sural, Ulnar, Median) and three motor (Peroneal, Ulnar, Tibial) nerves. RESULTS: The comparisons were done between different parameters of nerve conduction studies with the neurological scores in undetectable and detectable groups using Pearson's chi square test. The amplitudes, velocities, latencies, outcome and grading of neuropathy in nerve conduction studies when compared with neurological detection scores showed a significant relation in each group regarding evaluation (p = 0.005, p = 0.004, p = 0.05, p = 0.00001, p = 0.003 respectively). CONCLUSIONS: Diabetic Neuropathy Symptom Score and Diabetic Neuropathy Examination Score together can help in prompt evaluation of the diabetic sensorimotor polyneuropathy though nerve conduction study is more powerful test and can help in diagnosing subclinical cases.

A cross-cultural comparison of British and Pakistani medical students' understanding of schizophrenia.

This study aimed to compare British, British Pakistani and Native Pakistani (from Pakistan) medical students' beliefs about the manifestation, causes and cures of schizophrenia, prior to any psychiatric training. A total of 305 participants completed a questionnaire on general beliefs about people with schizophrenia, causal explanations concerning the aetiology of schizophrenia and the role of hospitals and society in treating people with schizophrenia. It was predicted that compared with the British and British Pakistanis, the Pakistanis would have more negative beliefs and attitudes, considering people with schizophrenia to be more dangerous and unpredictable; they were also expected to use more superstitious beliefs to explain the cause of schizophrenia and its symptoms; as well as believe more in seeking help from God and faith healers. There was strong evidence to suggest that Pakistanis possessed more negative beliefs and attitudes about people with schizophrenia, but there was no evidence to indicate that Pakistanis believed more in superstitious causal explanations. Pakistanis were more likely to consider seeking help from faith healers, but not God, compared with British Pakistanis and the British. Results confirm previous European-Asian difference in the understanding of the cause, manifestation and cure of schizophrenia. The impact of traditional and Western cultural influences on British Pakistanis is considered.

Effect of beta adrenergic antagonist on the production of testosterone by rat's Leydig cells.

BACKGROUND: The Leydig cell is the source of the male sex steroids, or androgens, which are essential for the maintenance of the male phenotype, the male gonads. and spermatogenesis. It has been reported that patients taking beta-blockers experience sexual dysfunction. The purpose of this study was to explore the direct mechanism by which beta adrenergic antagonist exert its' effect on testosterone production by rat Leydig cells. METHODS: Enzymatic dispersion of rat Leydig cell was done. About 85000 cells per tube were taken. After removal of endogenous testosterone by preincubation, The rat Leydig cells were incubated with varying concentrations of Atenolol: [Selective Beta-Adrenergic Antagonist] (10(-6), 10(-7) and 10(-9) M) with or with out LH 250 IU for three hours to measure the testosterone release by RIA. RESULTS: Atenolol, in varying concentrations caused a significant (P<0.05) reduction in testosterone release by the rat Leydig cells as compared to the basal release of testosterone in a dose-dependent fashion. Atenolol decreased the testosterone release by LH stimulated Leydig cells more significantly (P<0.001) as compared to the effects of Atenolol produced on non-stimulated Leydig cells. CONCLUSION: The current data indirectly suggest that Atenolol inhibits testosterone releasee via mechanism involving decrease production of cAMP but not affecting the enzyme activities of steroidogenesis.

Frequency of snoring and symptoms of sleep apnea among Pakistani medical students.

BACKGROUND: Snoring and its related problem, sleep apnea, are very common. They occur in all ages and both sexes. Frequency varies in different communities therefore studies of other countries are invalid for Pakistan. The aim of this study is to assess the frequency of snoring and emergence of symptoms of sleep apnea among the affluent class young adult Pakistani population. METHODS: Subjects were evaluated through a questionnaire. Questions pertained to quality of sleep, intensity and frequency of snoring and presence of symptoms such as waking up choking, morning headaches and morning dry mouth. Data were collected for age, sex, height and weight. Subjects were also asked if they took alcohol or any drugs. RESULTS: A total of 111 subjects, M:F = 2:3, age range between 18-23 years, responded to the survey. The frequency of snoring was 27% in males and 12% in females, with males admitting to snoring more night in the week than the females. 92% of both males and females graded their snoring as being softer than the sound of talking. 15% of the males and 38% of the females said they snored in every body position. Percentages of male and female snorers exhibiting symptoms of sleep apnea were very similar, with choking arousals at 6% and 5% respectively. CONCLUSION: This study was done on the young Pakistani population for the determination of frequency of snoring and the emergence of symptoms of sleep apnea. The results are similar to studies done on the adult population with snoring more common and louder among the males.