Visual evoked potentials’ responses in hypothyroidism and hyperthyroidism

Background: Visual Evoked Potentials (VEP) provides important diagnostic and prognostic information regarding the functional integrity of the visual system. This study, describes the effects of less or excess thyroid hormones of adults in visual conduction that helps to know the progression to neurological functional defects.Methods: The study was done in 75 consenting subjects (hypothyroid = 24, hyperthyroid = 25, euthyroid = 26). The VEP parameters N75, P100, N145 latencies and its amplitudes within different thyroid status (hypothyroidism, hyperthyroidism and euthyroidism) were compared. One way ANOVA was used to compare VEP parameters among three groups and Pearson’s correlation to find relation between thyroid hormones and VEP parameters.Results: There was positive correlation of 0.335, 0.338 and 0.301 between amplitudes of N75, P100 and N145 waves and fT3 hormone respectively. Furthermore, fT4 showed a positive correlation of 0.186 and 0.185 with the wave amplitudes of N75 and N145 waves respectively and negative correlation of TSH levels of -0.492, -0.280, -0.397 with amplitudes of N75, P100, N145 waves respectively. Hyperthyroid group had higher in VEP latency than euthyroid group in N75 (73±5.77 vs. 68.54±4.32), P100 (106.42±9.74 vs. 100.94±8.17) and N145 (153.03±16.39 vs. 144.37±7.02) waves. Similarly, hypothyroid group had higher in VEP latency than euthyroid group in N75 (72.12±6.34 vs. 68.54±4.32) wave.Conclusions: Both hypothyroidism and hyperthyroidism led to conduction delay in adults, possibly adversely affecting function of myelin. The prominent visual evoked potential abnormalities in hyperthyroidism and less change in hypothyroidism show that the visual neuropathy is more common in hyperthyroidism.

Iodine Status among School Children of remote Hilly regions of Nepal.

A cross-sectional study was conducted in remote hilly areas (Shree Antu and Ranke) of eastern Nepal to assess iodine status among school children aged 6-12 years. Urinary iodine excretion was estimated in 292 urine samples. The median urinary iodine excretion was 187.52 μg/L, and 33.6% children have insufficient urinary iodine excretion.

Application of Liquid Chromatography-Mass Spectrometry for Detecting Terlipressin Levels in Rat Plasma.

This work describes a liquid chromatography– electrospray tandem mass spectrometry method for detection of terlipressin in Wistar rat plasma in the low nano-gram range. Terlipressin is a synthetic analogue of the antidiuretic hormone arginine vasopressin and it might be used when Arginine vasopressin (AVP) is not readily available. For experimental evaluation of the pharmacokinetics of terlipressin, rats can be injected 3.0 μg/kg or 6.0 μg/kg i.v. of terlipressin and blood can be collected for Mass spectrometry characterization of terlipressin which can be performed with a high-resolution Orbitrap-based mass spectrometer.

LH/FSH ratio: a better marker of secondary amenorrhea in patients from eastern Nepal.

FSH, LH and prolactin (PRL) levels were assessed by ELISA in 50 cases with secondary amenorrhea and 52 age and sex-matched healthy controls from eastern Nepal. Cases were diagnosed by differential diagnosis, and data were analyzed using standard statistical tools. Early stage (3-6 months) and long standing (> 6 months) secondary amenorrhea had no effect (p > 0.05) in hormonal parameters studied. Pulse, SBP, DBP, weight, height, age of menarche, cycle interval and duration of flows were homogenous (p > 0.05) in patients and controls. Median age of menarche, median cycle interval and median duration of flows in healthy subjects were 14 years, 30 and 4 days respectively. FSH in cases (15.38 +/- 7.24 mU/ml) was significantly elevated (p < 0.01) as compared to controls (9.38 +/- 6.34 mU/ml). LH in cases (35.44 +/- 24.35 mU/ml, median 36.5 mU/ml) was significantly (p < 0.01) elevated by almost 5 times of its mean value and 9 times of its median value as compared to that of controls (7.58 +/- 6.604 mU/ml, median 4.2 mU/ml). LH/ FSH ratio in cases (2.44 +/- 1.73, median 2.00) was significantly higher (p < 0.01) as compared to controls (0.82 +/- 0.42, median 0.76). FSH e"12 mU/ml, LH e"10 mU/ml and LH/FSH ratio e"1 cut offs were significantly associated (p = 0.000 in each) with the cases as revealed by chi-square analysis, and LH/FSH ratio e"1 (Sensitivity = 84.0%, specificity = 77.0%) was found to be a stronger marker of secondary amenorrhea. As the elevation of LH was more pronounced than that of FSH, this study hints towards possible LH receptor mutation, which is generally found in premature ovarian failure (POF). Diagnosis of cases in this region may need a new cut off level for POF, as the elevation of FSH itself was not as pronounced as reported by other workers.

An evaluation of training of teachers in medical education in four medical schools of Nepal.

Effective teaching is a concern of all teachers. Therefore, regular teachers' training is emphasized globally. B. P. Koirala Institute of Health Sciences (BPKIHS), a health science deemed university situated in eastern region of Nepal has an established Medical Education unit which attempts to improve teaching-learning skills by training faculty members through organizing regular medical education training programs. The aim of the present study was to assess the effectiveness of 3-day training workshop on "Teaching-learning methodology and Evaluation" held in four different medical colleges of Nepal. The workshop was targeted at middle and entry level of health profession teachers who had not been previously exposed to any teacher's training program. The various components, such as teaching-learning principles, writing educational objectives, organizing and sequencing education materials, teaching-learning methods, microteaching and assessment techniques, were incorporated in the workshop. A team of resource persons from BPKIHS were involved in all the four medical institutions. The collection data had two categories of responses: (1) a questionnaire survey of participants at the beginning and end of the workshop to determine their gain in knowledge and (2) a semi-structured questionnaire survey of participants at the end of workshop to evaluate their perception on usefulness of the workshop. The later category had items with three-point likert scale (very useful, useful and not useful) and responses to open-ended questions/ statements to document participants general views. The response was entered into a spreadsheet and analyzed using SPSS. The result showed that all participants (n = 92) improved their scores after attending the workshop (p < 0.001). Majority of respondents expressed that the teaching-learning methods, media, microteaching and evaluation techniques were useful in teaching-learning. The workshop was perceived as an acceptable way of acquiring teaching-learning skills but 39.4% participants expressed that the duration of the workshop was too short. The overall impression about trainers was very positive. Therefore, regular organization of such workshops with addition of new advances in medical education would be highly beneficial to improve teaching learning skill of medical teachers.

Evaluation of lipid peroxidation product, nitrite and antioxidant levels in newly diagnosed and two months follow-up patients with pulmonary tuberculosis.

This case-control study followed by a longitudinal cohort study was undertaken to evaluate the level of lipid peroxidation product malondialdehyde (MDA) and nitrite as an indirect measurement of nitric oxide vis-à-vis the levels of antioxidants vitamin C and vitamin E in pulmonary tuberculosis. Fifty-six sputum smear-positive cases of pulmonary tuberculosis based on Ziehl-Neelsen (ZN) staining and 50 healthy controls without any systemic disease were included in this study. Thirty-five cases were longitudinally followed up with standard antituberculosis chemotherapy (ATT) for two months. Serum levels of malondiadehyde (MDA), nitrite, and plasma levels of vitamins C and E were measured. The mean serum MDA level was significantly higher (8.1 +/- 1.61 nmoles/ml) in PTB patients before commencement of ATT as compared to healthy controls (3.45 +/- 1.7 nmoles/ml) (p=0.0001) and decreased significantly after 2 months of ATT (3.84 +/- 1.28 nmoles/ml) (p=0.0001). The mean serum nitrite level (47.19 +/- 18.44 micromol/l) was significantly elevated before ATT compared to healthy controls (32.89 +/- 11.94 micromoles/l) and decreased significantly after 2 months of ATT (27.71 +/- 11.97 micromoles/l) (p=0.0001). The mean plasma levels of vitamins C (0.88 +/- 0.33 mg/dl) and E (0.79 +/- 0.24 mg/dl) in PTB patients before commencement of ATT were lower than healthy controls (1.42 +/- 0.38 mg/dl) and (1.35 +/- 0.35 mg/dl), respectively (p=0.001). There was a significant increase in vitamin C levels after 2 months of ATT (1.19 +/- 0.40 mg/dl) compared to before ATT (0.83 +/- 0.31 mg/dl) (p=0.0001), but no significant change in mean plasma vitamin E level before and after 2 months on ATT was found. Elevated malondialdehyde and nitrite levels with concomitant depressed vitamin C and E levels are indicative of lipid peroxidation and oxidative stress. The decrease in levels of malondialdehyde and nitrite with subsequent increase in vitamin C levels after two months of follow-up indicate a good response to treatment with standard ATT. Hence, the extent of oxidative stress in PTB can be evaluated by analyzing lipid peroxidation product, antioxidant and nitric oxide levels.

Comparative study of cerebrospinal fluid adenosine deaminase activity in patients with meningitis.

Cerebrospinal fluid (CSF) adenosine deaminase (ADA) activity in tubercular meningitis (TBM) patients (n=20), non-tubercular meningitis (NTBM) patients (n=10) and non-tubercular non-meningitis (NTBNM) cases (n=15) were measured by the method based on Berthlot's reaction. The mean CSF ADA activity in TBM (13.62 +/- 8.45 IU/L) was found to be significantly higher as compared to NTBM (6.51 +/- 2.41 IU/ L, p<0.001) and NTBNM (2.35 +/- 1.16 IU/L, p<0.0001) respectively. The sensitivity and specificity of CSF ADA activity was 85.0% and 88.0% respectively at cut-off value of 6.97 IU/L to diagnose tubercular meningitis. The specificity and sensitivity of CSF ADA for TBM was found to be 85.0% and 70.0% as compared to NTBM and 85.0% and 100.0% as compared to NTBNM. We propose that estimation of that ADA activity in CSF of TBM patients, using a cut off value 6.97 IU/L can diagnose differentially tubercular meningitis. Since, most developing countries have the dubious distinction of having higher prevalence and incidence of tubeculosis and lack of well equipped laboratory services for proper diagnosis of tubercular meningitis, measurement of CSF ADA activity can be a better and reliable approach for the rapid diagnosis and management of tubercular meningitis vis a vis other types of meningitis.

Serum nitrite level and adenosine deaminase activity is altered in visceral leishmaniasis.

In this study we sought to determine if there is alteration in nitric oxide (NO) production and adenosine deaminase (ADA) activity among patients with visceral leishmaniasis (VL) and the effect of four weeks of chemotherapy on these levels. Fifty-three VL patients diagnosed clinically and by direct demonstration of the LD bodies in the bone marrow smear were studied. They were treated with Sodium Stibogluconate and sampled at the baseline and four weeks. Forty-three healthy individuals coming from the same endemic area were taken as control. Total nitrite (NO2- and NO3-) as an index of NO production and ADA activity was measured spectrophotometrically. Serum nitrite level decreased significantly in patients as compared to the healthy individuals but significantly increased following 4 weeks of chemotherapy. Conversely, Increased ADA activity was observed in the beginning of treatment and decreased significantly with successive 4 weeks of chemotherapy. It seems a negative correlation between NO level and ADA activity. This result indicates parasite induced evasion of NO and activation of T lymphocytes during immunopathogenesis of VL. Therefore, assessment of NO metabolites may be useful marker in the evaluation of the effector mechanism of macrophages and clinical manifestation of patients.

Diagnostic utility of adenosine deaminase (ADA) activity in pleural fluid and serum of tuberculous and non-tuberculous respiratory disease patients.

Adenosine deaminase activity (ADA) was assayed in pleural fluid and serum of 42 subjects with pleural effusion. Twenty-nine of them had TB pleural effusion and the remaining 13 had pleural effusion due to non-TB respiratory diseases. Serum adenosine deaminase activity were also measured in 32 pulmonary tuberculosis patients without pleural effusion and equal numbers of healthy controls without systemic diseases for comparative analysis. The patients attending the medicine out-patient department (MOPD) of the B. P. Koirala Institute of Health Sciences, Dharan, Nepal were taken as study subjects. Serum and pleural fluid ADA activities were assayed spectrophotometrically by the method of Guisti and Gallanti. The mean serum ADA activity was significantly increased in patients with tubercular pleural effusion (34.53 +/- 10.27 IU/l) compared to pulmonary tuberculosis patients without pleural effusion (26.54 +/- 4.76 IU/l), (p = 0.004), those with non-TB respiratory disease (16.71 +/- 5.16 IU/l), (p = 0.0001) and healthy controls (15.53 +/- 4.4 IU/l) (p = 0.0001). The mean ADA in the pleural fluid of tubercular pleural effusion patients (90.29 +/- 54.80 IU/l) was significantly higher compared to those with non-TB respiratory disease (24.43 +/- 9.28 IU/l) (p = 0.0001). Using the lowest cutoff value for enzyme activity in the serum of patients with TB pleural effusion (25 IU/l), a test sensitivity of 72.41% and specificity of 81.53% were obtained. Using the lowest cutoff value for enzyme activity in pleural fluid of patients with TB pleural effusion (45 IU/l) the sensitivity and specificity for diagnosis were 76.10% and 100%, respectively. Therefore, the measurement of ADA in tubercular pleural effusion has a utility in the diagnosis of tuberculosis when other clinical and laboratory tests are negative.

Age related changes in cholesterol level among the patients with subclinical hypothyroidism in eastern Nepal.

This study was undertaken at Biochemistry Department (BPKIHS) from 2001 to 2002. The aim of this study was to assess whether subclinical hypothyroidism is associated with abnormal cholesterol level in different age groups. Of the cases referred to the department, 398 euthyroid controls, 189 hypothyroid cases, 179 hyperthyroid cases and 181 subclinical hypothyroid cases were enrolled for further analyses. Both the sexes showed increased total cholesterol levels in hypothyroidism, and were not significantly changed in hyperthyroidism than in euthyroid controls. Female subclinical hypothyroid cases of age group 45-59 years and both the male and female cases of age group > or = 60 years had significantly (p < 0.01) elevated total cholesterol levels (196 +/- 37.36 mg/dl vs.169.37 +/- 29.12 mg/dl, 211.5 +/- 30.48 mg/dl vs. 151.54 +/- 55.84 mg/dl and 225 +/- 25.05 mg/dl vs. 181.73 +/- 32.95 mg/dl respectively) as compared to euthyroid controls. When data were analyzed at 33 and 45 years of age cut offs, the cases of > or = 33 years age in both hypothyroid male and female showed significantly (p < 0.01) elevated cholesterol levels (222.66 +/- 29.26 mg/dl vs. 156 +/- 37.09 mg/dl and 231.66 +/- 46.17 mg/dl vs 198.1 +/- 48.72 mg/dl respectively) where as subclinical hypothyroid female showed increased total cholesterol level (211 +/- 31.2 mg/dl vs. 157.95 +/- 45.92 mg/dl) at > or = 45 years age cut off. It is concluded that hypothyroidism not the hyperthyroidism is associated with increased total cholesterol level in the cases of this region, and we advise routine screening for cholesterol level in both the sexes of hypothyroid (for > or = 33 years) and female subclinical hypothyroid (for > or = 45 years) cases in this area, as they have high risk for higher cholesterol levels and developing related disorders.

Easy approach to DNA shuffling: its potential implication in health sciences.

Directed evolution experiments rely on the cyclical application of mutagenesis, screening and amplifications in a test tube. During the laboratory evolution of biological molecules, recombination has been used to generate novel sequences in a process known as DNA shuffling. DNA shuffling is a recently developed technique that allows accelerated and directed protein evolution for desired properties in vitro, which recombines and evolves genes to rapidly obtain molecules with improved biological activity and fitness. DNA shuffling is generally achieved by DNaseI treatment and by PCR. This has led to the creation of novel proteins for a wide range of applications. The use of improved enzymes for medical, industrial and environmental purposes is prevalent today, and will be expanding. New applications in vaccine development and disease diagnosis are among the key features of DNA shuffling. However, directed evolution currently requires an uncertain, typically large number of labor-intensive and expensive experimental cycles before proteins with improved function are identified. A simplified and low-cost DNA shuffling protocol for random recombination of homologous genes in vitro is described here.

De Ritis ratio as diagnostic marker of alcoholic liver disease.

Patients suffering from Alcoholic Liver Diseases (ALD) are often diagnosed by spectrum of physical manifestations and laboratories abnormalities. Among biochemical abnormalities De Ritis Ratio (AST/ALT ratio) is more sensitive during any phase of the disease. This ratio is based on common tests of liver function test and can be investigated in any laboratory and is more relevant in countries like Nepal where alcohol abuse is a major cause of liver disease. Clinically diagnosed 103 ALD cases and 73 healthy controls were enrolled for the study. Selected parameters of liver function tests were analyzed by Vitalab Selectra-2 autoanalyser using Merck diagnostic kits and statistically analyzed by student "t" test. The De Ritis ratio was calculated from serum AST and ALT values and was found 2. 30:1 in patients compared to of 1.10:1 in control group. AST and ALT value showed mild to moderate elevation as it was 124.80 +/- 86.24 IU/L and 54.21 +/- 39.72 IU/L in patients compared to 35.00 +/- 23.49 IU/L and 31.48 +/- 17.79 IU/L in controls. The increase in AST and ALT level in patients was statistically significant (p < 0.001) and (p < 0.01) respectively. > or = - Glutamyl Transferase showed 425.26 +/- 36.40 IU in alcoholics compared to 70.55 +/- 27.35 IU/L in controls, a significant increase observed (p<0.001) However Alkaline Phosphatase activity was observed within normal limit. Serum Total Protein (TPR) and Albumin (ALB) showed 6.86 +/- 1.01 g/dl and 2.71 +/- 0.78 g/dl in patients with Albumin: Globulin ratio of 0.61:1 compared to 7.51 +/- 1.74 g/dl and 4.03 +/- 0.61 g/dl in controls with the ration of 1.15:1, a significant decrease in albumin (p < 0.001) without alteration of Total Protein in patients. Total and Direct bilirubin showed 2.32 +/- 1.10 mg/dl and 1.26 +/- 0.88 mg/dl in alcoholics higher than the control of 1.06 +/- 0.60 mg/dl 0.38 +/- 0.31 mg/dl (p<0.001). Diagnosis of ALD is straight forward with history-and compatible clinical features but alcoholic's denial and under estimation of alcohol abuse becomes an obstacle in confirmation. A mild to moderate disproportionate elevation of AST than ALT activity making De Ritis Ratio > 2:1, supported by reversal of Albumin/globulin ratio facilitates the diagnosis.