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Prasad, B K
- QTc Interval: Gender Difference and effect of Menstrual Cycle
Authors
1 Community Medicine Dept, SSIMS& RC, Davangere, Karnataka
Source
International Journal of Physiology, Vol 1, No 2 (2013), Pagination: 91-96Abstract
Context: Women are more predisposed to ventricular arrhythmias than men. The occurrence of Torsades-de-pointes is increased with the degree of QT interval prolongation, and female gender is a known risk factor for its occurrence. Drug induced QT prolongation are greater in women than in men. Sex hormones have potential role on the mechanisms involved in the cardiac repolarization
Aims: To note gender difference and menstrual cycle effect on cardiac electrophysiology
Settings and Design: Case-control study
Method and Material: Electrocardiogram (ECG) was recorded in randomly selected healthy 51 men and 51 women; aged between 17-20 yrs. ECG in women was taken during menstrual, proliferative and luteal phases of menstrual cycle. Basal body temperature throughout menstrual cycle was recorded in women to confirm that recordings were done in respective 3 phases of menstrual cycle. RR interval, QT interval and QTc interval were noted from Lead II recording of the subjects.
Statistical analysis used: Student's unpaired T test, Repeated measures ANOVA
Results: Study group was age matched. There was statistically highly significant gender difference during menstrual phase (p<0.001) and proliferative phase (p<0.001), and significant difference during secretory phase (p=0.008). Difference in mean QTc interval in women during different phases of menstrual cycle is statistically not significant (p=0.08).
Conclusions: There is gender difference in QTc interval of cardiac repolarization. There is no statistically significant difference in QTc interval in women during different phases of menstrual cycle. This difference is higher during menstrual phase in women
Keywords
QTc Interval, Gender Difference, Menstrual Cycle, Cardiac Repolarization, ECGReferences
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- Study of Diurnal Variation of Pulmonary Function Test
Authors
1 Dept of Physiology, SSIMS & RC Davangere
2 II Phase MBBS, SSIMS & RC Davangere, Karnataka
Source
Indian Journal of Public Health Research & Development, Vol 4, No 2 (2013), Pagination: 173-178Abstract
Pulmonary function has circadian rhythm in humans proven in diseased in conditions. These variations will contribute to better understanding the relationship between biorhythms and lung physiology for better management of pulmonary diseases.To study PFT in medical students during different time of the day and to study whether there is diurnal variation in PFT .The I MBBS students chosen as subjects were apparently normal and non-smokers. The study group included 113 students. They underwent PFT during different time of the day, i.e., at 6am, 11am, 4pm and 9pm. PFT was done using computerized Spirometer and the parameters studied were FEV1, FVC, FEV1/FVC, PEF, FEF25- 75% and FEF.2-1.2L. The data was tabulated and statistically analyzed. There were changes in all the PFT parameters recorded during different time of the same day. Mean of FEV1 and FVC were highest in the recording taken at 9:00pm. % change noted was 1.74% and 1.32% respectively, when compared to the recording at 6:00am. Mean of FEV1/FVC ratio also showed diurnal rhythm with highest % at 11:00am and lowest % at 6:00am. The % change noted was 0.76%. Mean of PEFR, FEF25-75% and FEF0.2-1.2L showed diurnal rhythm. They were high in the recording done at 4:00pm and low in the recording done at 6:00am. % change noted in PEFR, FEF25-75% and FEF.2-1.2L were 2.25%, 3.66% and 2.08% respectively. % change noted for each parameter was statistically not significant. The diurnal variation in PFT parameters is noted in healthy subjects. The % change noted is minimal in young healthy individuals. This diurnal rhythm amplitude increase in asthma and bronchitis patients.Keywords
PFT, Computerized Spirometer, Diurnal VariationReferences
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- Study of Effect of Smoking on Auditory Acuity
Authors
1 Dept. of Physiology, SSIMS & RC NH-4 Bypass Road, Davangere, Karnataka, IN
2 Dept of Physiology, SDUMC, Kolar, Karnataka, IN
Source
Indian Journal of Public Health Research & Development, Vol 4, No 4 (2013), Pagination: 162-167Abstract
Background: The relationship between smoking and hearing loss has been debated. Smoking appears to have an effect on auditory acuity and the proposed mechanisms are the direct oxidative damage on cochlea caused by toxic substances inhaled with the cigarette smoke or to the acceleration of the atherosclerotic process in the cochlear artery.
Objectives: To record the auditory thresholds of age matched male smokers and non-smokers of age group 20-40 yrs, using pure tone audiometer and compare the auditory thresholds between the groups.
Method: Age matched male 100 smokers and 100 non-smokers were subjected to pure tone audiometric assessment. The smoking history in terms of pack-years was also noted. The data was statistically analyzed.
Results: Smokers group were significantly hearing impaired than the non-smokers group. The hearing impairment was noted at all frequencies tested. Higher frequencies were more affected than the lower frequencies. The auditory thresholds of smokers had significant positive correlation with smoking history, indicating that auditory thresholds rise as the number of pack-years increase.
Conclusion: Smoking causes hearing impairment. The higher frequencies are more affected. The auditory thresholds rise as the number of pack-years increase.
Keywords
Smoking, Hearing Loss, Pure Tone Audiogram, Auditory Thresholds, Sensorineural Hearing LossReferences
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