International Physiology

  Ageing/ Aging is the process of becoming older. Ageing can refer to single cells within an organism which have ceased dividing (cellular senescence) or tothe population of a species (population ageing). Aging occurs due to accumulation of physical, psychological, and social changes in a human being over time. Ageing is one of the risk factors for most human diseases. Approximately two thirds of the 150,000 of total deaths occurring globally per day is due to age related factors. Aging is characterized by a progressive, generalized impairment of function, resulting in an increasing vulnerability to environmental challenge and a growing risk of disease and death. Ageing and mortality started with evolution of sexual reproduction and emergence of the fungal/animal kingdoms approximately a billion years ago. Normal human cells die after about 50 cell divisions known as Hayflick Limit. There are several theories postulated for the cellular mechanism of ageing. They are broadly divided into two main categories: Programmed and Damage­related. Cellular senescence has been attributed to the shortening of telomeres at each cell division. DNA damage theory forms the common basis of both cancer and ageing. Intrinsic causes of DNA damage are the most important drivers of ageing. According to Free radical theory oxidative reaction leads to the formation of molecular species with unpaired electrons which makes them highly reactive known as Free radicals. Ageing affects the various systems of our body. Prevention and delay of ageing can be done by lifestyle modification. The amount of sleep has great impact on mortality. Physical exercises may also increase life expectancy. Avoidance of chronic stress slows loss of telomeres and decreases cortisol levels. Caloric restriction also delays ageing. 

Keywords: Ageing; Hayflick Limit; Telomere; Free Radicals; Caloric Restriction.

Background: Yoga is a physical, mental, and spiritual discipline that began in India. Since its inception, around the 5th or 6th century BC, yoga has attained lot of importance as far as the physical and mental health of a common man is concerned. The most common parameter to assess the physical fitness is cardiovascular function usually blood pressure; more the stress, high the blood pressure. The young generation is facing more stress in present scenario in all walks of life and medical students are not exceptions. Objective: To study the effect of short-term yogic practices on blood pressure in young healthy medical students. Methodology: The study was conducted on 36 healthy medical students (21 males and 15 females) in the age group of 17-21 years in the Department of Physiology, M.G.M. Medical College, and Maharaja Yashwantrao Hospital, Indore. An informed consent was taken after fulfilling the inclusion and exclusion criteria. Blood pressure was measured by using mercury sphygmomanometer before the participants started yoga practices. The participants performed yoga practices in the morning for one hour daily, six days in a week, for four weeks under the guidance of yoga teacher. The yoga practices consisted of Prayer, Omkar recitation, asana, Pranayama, and breathing exercises. Blood pressure was again measured after the completion of yoga session. Data thus collected compiled, tabulated, and analyzed statistically by using students’‘t’ test. Observation and Result: There was significant reduction in both systolic and diastolic blood pressure. The reduction in systolic blood pressure was more marked in males (p value 0.006) while reduction in diastolic blood pressure was more marked in females (p value 0.015). Conclusion: On the basis of these results we can conclude that yogic practices lowers blood pressure; which can be useful not only therapeutically but also as a preventive measure.

Keywords: Yoga; Blood Pressure; Syphygmomanometer; Students ‘t’ Test.

  Introduction: Hypertension is an iceberg disease which is a risk factor for cardiovascular mortality. 45% of children with hypertensive parents have got a possibility of developing hypertension. HRV is a tool to identify autonomic dysfunction. Materials and Methods: 50 normotensive male cases with the parental history of hypertension and 50 age­matched healthy male controls were selected for the study. ECG was digitally recorded using BPL Cardiart 1087 ECG machine & Analog Digital Converter (NI­DAQ 7.5) and analyzed for SDNN, LF, HF, LF/HF ratio and E: I ratio. Results & Conclusion: SDNN, E: I ratio, HFnu were significantly reduced and LFnu & LF/HF ratio was significantly increased in cases. This indicated a reduced parasympathetic activity and increased sympathetic activity. 

Keywords: Heart Rate Variability; Cardiac Autonomic Activity; Hypertension; Sympathetic Overactivity; Parasympathetic Withdrawa

  Introduction: Reaction time (RT) denotes time taken by an individual to react to external stimulus. RT plays a very important role in our lives as its practical implications may be of great consequences. Fast RTs can give rewards (e.g. in sports), whereas slow RT can lead to grave consequences (e.g. driving and road safety matters). Factors that can affect the human auditory and visual reaction time include age, gender, left or right hand, practice, fatigue, exercise etc. The present study was conducted, which was aiming to find out immediate effect of exercise on auditory and visual reaction time in medical students. Material and Methods: For determination of VRT(Visual Reaction Time) and ART(Auditory Reaction Time) we have used reaction time apparatus designed by Anand agency pune.VRT and ART were determined in 120 healthy medical students in the age group of 17 to 25 years before exercise. All the subjects were asked to perform 5 minute warm up followed by 15­20 minutes exercise on the stationary bicycle (Body Gym Stamina Air Bike) at the speed of less than 5 mph. Data was analyzed by unpaired “t” test. We found both ART and VRT was significantly decreased immediately after physical exercise (p<0.05). Conclusion: Thus our study showed both VRT and ART was significantly decreased in medical students immediately after physical exercise on stationary bicycle. 

Keywords: Auditory Reaction Time; Physical Exercise; Reaction Time; Visual Reaction Time.

  Context: Patients with diabetes have more number of coronary risk factors. Early identification of these risk factors is essential to prevent morbidity and mortality among them. Aims: To study prevalence of coronary risk factors in patients with type II diabetes. Settings and design: hospital based cross sectional study carried out at Department of Physiology Gandhi Medical College, Bhopal. Methods and material: 60 patients of type II diabetes were included as per criteria of World Health Organization (1999). All patients were examined for presence of coronary risk factors like age, BMI, waist circumference, waist hip ratio, smoking, physical activity, hypertension, and dyslipidemia. Statistical analysis: The data was presented as mean and standard deviation and proportions. Results: Prevalence of overweight and obesity was equal among both the sexes. Higher waist circumference prevalence was more in males but central obesity was equal in both the sexes. Prevalence of smoking or tobacco use was very high in males. Overall physical inactivity prevalence was more in females. Prevalence of hypertension as well as that of dyslipidemia was also more in females. As the BMI increased, as the waist circumference increased, and as the duration of disease increased, the prevalence of coronary risk factors increased. Conclusion: Prevalence of coronary risk factors was very high in the present study.

Keywords: Smoking; Hypertension; Dyslipidemia; Diabetes; Risk Factors; BMI; Waist Circumference.

  Background: Blood grouping, Bleeding and Clotting time are routinely performed useful hematological tests, mainly done before blood transfusion and any surgery in hospitals. Aims and Objectives: To determine the blood group and to evaluate the association of ABO blood groups with BT and CT among medical students. Materials and Methods: This study was conducted on medical students, in the Department of Physiology at Karwar Institute of Medical Sciences (KRIMS), Karwar. Total of 299 medical students participated. Out of which 161 were males and 138 females. Blood was collected by finger prick method. Blood grouping was done with the standard anti sera technique. BT and CT were determined by the Duke’s filter paper method and Wright’s capillary glass tube method respectively. Blood group distribution was expressed in percentage and their correlation with BT, CT was analyzed by Chi­square analysis and Z­test. Results: In our study it was found that the percentage distribution of ‘ABO’ blood group showed predominance of blood group ‘O’ followed by ‘B’, ‘A’ & ‘AB’. Our study also shows that bleeding and clotting times are influenced by blood group and gender. Bleeding time was more in females than males and it was statistically significant (p<0.0180). Bleeding time was more in females of blood group O and B, but it was statistically significant only in O blood group (p<0.0016). Clotting time was more in females than males and it was statistically significant (p<0.0118). Clotting time was more in ‘O’, ‘B’ & ‘AB’ blood group in females as compared to males & it was statistically significant (p<0.05). Conclusion: In our study, O was the most common while blood group AB was the least. Bleeding time was more in females of blood group O and B, but it was statistically significant only in O blood group. Clotting time was more in ‘O’, ‘B’ & ‘AB’ blood group in females as compared to males and the difference was statistically significant. 

Keywords: ABO Blood Group; Bleeding Time; Clotting Time; Medical Students.

  Background: Conjugate Lateral Eye Movements (CLEMs) may determine the extent of the relative activity of the two cerebral hemispheres during an on­going cognitive task. Several studies have documented more rightward CLEMs for verbal questions with left hemispheric activity and more leftward CLEMs for spatial questions with right hemispheric activity, while others have suggested CLEMs to be individualspecific independent of the questions. Thus previous findings are mixed and uncertain. This study questions the validity of CLEMs as a measure of functional laterality. Methods: The subjects were 400 healthy students in the age group 10­19 years. The subjects were required to orally respond to 10 verbal and 10 spatial questions. During each on­going cognitive process, the first observable CLEM direction was noted and categorised into rightward or leftward CLEM. Then whether this dependent on the type of question or was it an individual­specific stable trait was established. Results: In this study, majority of the subjects exhibited CLEMs pattern independent of the type of question (indicating subjects as either right­ or left­movers) and was statistically significant. There was no statistical significant difference between genders for the CLEMs pattern. Discussion: This suggests that the direction of gaze shift when people are thinking during different types of questions does not reflect the lateralization of underlying cerebral activity. This reflects that during an on­going cognitive task, CLEMs do not depend on preferential hemispheric activation, are independent of question type and is subjectspecific stable trait. Thus concluding that though CLEMs may have other neurophysiological implications, is not a valid index of functional laterality. The CLEMs pattern in future studies should be evaluated along with cerebral blood flow, positron emission tomography, etc.
Keywords: Conjugate Lateral Eye Movements; CLEMs; Functional Laterality; Verbal Questions; Spatial Questions; Cerebral Hemispheric Activation.

  The present study was carried out in the Department of Physiology, Mahatma Gandhi Memorial Medical College, Indore (M.P.). It is a type of cross­sectional study. Study was performed after taking permission from the Ethics and Scientific Review Committee M.G.M. Medical College M.Y. Hospital, Indore and permission letter from the Head of Department of Physiology MGM Medical College, Indore and from respective school authorities. The period of study was from March 2015 to February 2016. We had selected 100 school bus drivers of age group 20­50 years. Conclusion: With increase in BMI auditory reaction time also increases but the data obtained were statistically not significant (p>0.05). So from above findings we can conclude that shorter auditory reaction time in drivers makes important sense for safe driving and it can prevent road traffic accidents as well. Study Design: Cross­sectional Study.

Keywords: Auditory Reaction Time; High & Low Pitch; BMI & Bus Drivers.

  Context: Hypertension is a multifactorial disease and is a leading cause of cardiovascular morbidity. Depression is the most common psychiatric disorder in practice. Different studies have contradictory opinions about effect of depression on blood pressure. So, this study was planned to assess the association of depression scores and 24 hours ambulatory BP parameters. Aims: 1. To compare Beck’s depression score with day and night blood pressure load. 2. To compare Beck’s depression score in dippers and non­dippers. Methods and Material: The study included 60 healthy young adults of age between 20 to 35 years. Their day & night BP load and dipper state was assessed by 24 hours Ambulatory blood pressure measurement done by Contec Ambulatory Blood Pressure Monitor. Beck’s Depression Inventory­II (BDI­II) was used to calculate the depression scores in them. Independent T test was used to compare the depression scores and dipper state & BP load. Results: The mean BDI II scores of non­dippers were significantly higher than dippers [10.11±4.22 vs 6.14±4.21; p = 0.02]. Similarly, the mean BDI II scores of subjects with increased systolic day and night BP load were significantly higher than normal BP load [13.0±3.39 vs 6.2±3.86; p< 0.01 for day] and [12.0±3.85 vs 6.17±3.95; p< 0.01 for night]. Conclusions: As subjects with higher systolic BP load had more depression scores and also depression scores were higher in non­dippers. So, depression can lead to future cardiovascular morbidity and mortality. 

Keywords: Beck’s Depression Score; Dipper State; BP Load.  

  Introduction: Medical and dental students during their course of education may experience stress when their curricular demands tends to exceed their resources to deal with them, and they have been also reported to suffer from higher perceived stress compared to the general population and students in other academic fields. Current study aims to compare the level of stress in first year medical and dental students. Objective: To assess the perceived stress levels in first year medical and dental students. Method: A cross­sectional study was conducted among first year medical students of Al­Azhar medical college and super specialty hospital and first year dental students of al azhar dental college. Where, perceived stress scale ­ 10(PSS­10) was used for assessing the perceived stress levels. The data was entered in Microsoft excel and analyzed using SPSS version 16. Results: Of the 250 first year medical and dental students. Students reported PSS­10 mean score of 23.83(SD 7.08) scores ranging from 7­28. The mean PSS­10 for the medical students was 24.56(SD 7.24) and scores ranging from 8­38 and the mean PSS­10 score of the dental students was 24.66 (SD 7.27) and scores ranging from 7­37. There was no difference in stress levels between the two groups and gender. Conclusion: The study reported that there is a higher level of stress among the medical and dental student than compared to the general population. Also there is no difference in stress level between the two groups. 

Keywords: First Year Medical Students; First year Dental Students; Perceived Stress; South India

  The present study was carried out in the Department of Physiology, Mahatma Gandhi Memorial Medical College, Indore (M.P.). It is a type of cross­sectional study. Study was performed after taking permission from the Ethics and Scientific Review Committee M.G.M. Medical College M.Y. Hospital, Indore and permission letter from the Head of Department of Physiology MGM Medical College, Indore and from respective school authorities. The period of study was from March 2015 to February 2016. We had selected 100 school bus drivers of age group 20­50 years. Study Design: Cross­sectional Study. 

Keywords: Auditory Reaction Time; High & Low Pitch; BMI & Normal Population.