Effect of yoga practices on pulmonary function tests including transfer factor of lung for carbon monoxide (TLCO) in asthma patients.

Prana is the energy, when the self-energizing force embraces the body with extension and expansion and control, it is pranayama. It may affect the milieu at the bronchioles and the alveoli particularly at the alveolo-capillary membrane to facilitate diffusion and transport of gases. It may also increase oxygenation at tissue level. Aim of our study is to compare pulmonary functions and diffusion capacity in patients of bronchial asthma before and after yogic intervention of 2 months. Sixty stable asthmatic-patients were randomized into two groups i.e group 1 (Yoga training group) and group 2 (control group). Each group included thirty patients. Lung functions were recorded on all patients at baseline, and then after two months. Group 1 subjects showed a statistically significant improvement (P<0.001) in Transfer factor of the lung for carbon monoxide (TLCO), forced vital capacity (FVC), forced expiratory volume in 1st sec (FEV1), peak expiratory flow rate (PEFR), maximum voluntary ventilation (MVV) and slow vital capacity (SVC) after yoga practice. Quality of life also increased significantly. It was concluded that pranayama & yoga breathing and stretching postures are used to increase respiratory stamina, relax the chest muscles, expand the lungs, raise energy levels, and calm the body.

Antagonism of stimulation-produced analgesia by naloxone and N-methyl-D-aspartate: role of opioid and N-methyl-D-aspartate receptors.

The present study aims to investigate the influence of electrical stimulation of periaqueductal gray (PAG) following peripheral nerve injury and its modulation by naloxone and N-methyl-D-aspartate (NMDA). Chronic neuropathic pain was induced by chronic constriction injury of the sciatic nerve, and subsequently a cannula was implanted in the PAG area for the purpose of electrical stimulation and intra-PAG drug administration. Intra-PAG administration of morphine, ketamine, and their combination were found to elicit antinociceptive response on hot-plate test. Electrical stimulation of PAG was also observed to demonstrate decreased pain response on hot-plate test, and this effect was reversed by the administration of naloxone, NMDA, and their combination, when injected into the PAG area. These findings suggest that apart from the opioid receptors, probably NMDA receptors also have a role to play in stimulation-produced analgesia.

Event related potentials in anemic school--going girls of age group 8 to 10 years.

In the present study the effects of anemia on cognitive functions were studied in school going girls aged 8-10 years. The cognitive functions were assessed by Event Related Potentials (P300) and by the psychometric tests, i.e., Raven's progressive matrices test and Digit span attention test. The girls with Hb < 12 g/dl were classified into anemic and Hb > 12 g/dl into control group. Hematological values of the control group were significantly better than anemic group. P300 latency in the anemic girls was delayed as compared to control group but, no statistically significant difference was observed for P300 latency and P300 amplitude between the control group and the anemic group. The psychometric test scores for intelligence quotient and transformed quotient were also better but not statistically significant in control group of girls as compared to anemic girls. However, the hematocrit values showed a significant correlation with the P300 wave latency showing that the hematological status is associated with some effects on cognition.

Effect of pranayama & yoga-asana on cognitive brain functions in type 2 diabetes-P3 event related evoked potential (ERP).

BACKGROUND & OBJECTIVES: Electrophysiological evidence of delayed cognition as measured by P300, an evoked potential is observed in Diabetes mellitus. P300 (or P3) is a component of endogenous cerebral evoked response that assesses higher functions of the brain. Our study aims to see the role of pranayama and yoga-asana on P300 latency and amplitude in type 2 diabetic patients. METHODS: Sixty patients of type 2 diabetes were recruited from diabetic clinic and divided into two groups - control group on only conventional medical therapy and yoga-group on conventional medical therapy along with pranayama and yoga-asana. Basal recordings of P300 and blood glucose were taken at the time of recruitment and second recordings repeated after forty five days for both the groups. P300 was recorded on Nihon Kohden Neuropack mu MEB 9100 using auditory "odd-ball paradigm". The data were analysed using repeated measures analysis of variance (ANOVA) followed by Tukey's test at 5 per cent level of significance. RESULTS: Statistically significant improvement in the latency and the amplitude of N200, P300 was observed in the yoga group as compared to the control group. INTERPRETATION & CONCLUSION: Our data suggest that yoga has a beneficial effect on P300 and thus can be incorporated along with the conventional medical therapy for improving cognitive brain functions in diabetes.

Cognitive status in hypothyroid female patients: event-related evoked potential study.

AIM: Higher brain functions are adversely affected in hypothyroid patients. The central nervous system features of hypothyroidism include mental retardation, various cognitive and memory deficits that have been evaluated by different neuropsychological tests. In the present study event-related potentials (ERPs) have been used to assess the cognitive status of hypothyroid patients before and after treatment. METHODS: Twenty-six newly diagnosed hypothyroid female patients with a mean age of 31.85 +/- 8.57 years and 26 female controls with a mean age of 30.92 +/- 7.24 years were the subjects of the study. The ERPs were recorded on a computerized evoked potential recorder using the 10-20 system of electrode placement and the standard auditory 'oddball' paradigm. The first recording of ERPs was done at the time of diagnosis and the second recording was done 3 months after the start of treatment in a euthyroid state. RESULTS: Prolongation of latencies was found in the early ERP components (N100, P200 and N200) in hypothyroid patients compared to controls, while no significant group differences were found on P300. In the hypothyroid group all the ERP latencies decreased significantly after attainment of euthyroidism compared to pretreatment values. ERP amplitudes revealed no significant group differences between hypothyroid patients and controls, but significant amplitude increases were found on the waves of N200 and P300 after treatment compared with pretreatment values in the hypothyroid group. CONCLUSIONS: Hypothyroid patients showed prolongation of latencies only in the early ERP components compared to controls. In hypothyroid patients, ERP findings indicate a speeding of sensory and cognitive processing in a state of euthyroidism compared to the pretreatment condition.

Influence of pranayamas and yoga-asanas on serum insulin, blood glucose and lipid profile in type 2 diabetes.

A distinguishable feature of type 2 diabetes besides hyperglycemia and deranged lipid profile is an impaired insulin secretion, peripheral insulin resistance and obesity which has become a major health concern worldwide. India with an estimated 31million diabetics in 2000 and 79mllions by the yr 2030 has the highest number of type 2 diabetics in the world. In this study, we aimed to see if yoga-asanas and pranayamas have any influence in modifying certain biochemical parameters. Sixty patients of uncomplicated type 2 diabetes (age 35-60 yrs of 1-10 yrs duration) were divided into two groups: Group 1 (n=30): performed yoga along with the conventional hypoglycemic medicines and group 2 (n=30): patients who only received conventional medicines. Duration of the study was 45 days. Basal recordings of blood glucose (fasting and post-prandial), lipid profile and serum insulin were taken at the time of recruitment and the second reading after forty five days. Results showed a significant improvement in all the biochemical parameters in group 1 while group 2 showed significant improvement in only few parameters, thus suggesting a beneficial effect of yoga regimen on these parameters in diabetic patients.

Pulmonary functions in petrol pump workers: a preliminary study.

Occupational exposures to petrol/diesel vapors have been shown to affect functioning of different systems of the body. The present study was planned to assess the pulmonary functions in petrol pump workers (filling attendants) who are continuously exposed to petrol/diesel vapors during duty hours. Thirty healthy non-smoker males working in petrol pump for more than one year formed the study group, while thirty healthy non-smoker males from hospital staff served as control group. The pulmonary functions were assessed using computerized spirometer. The FVC and FEV1 were decreased in the study group while their ratio did not differ much. Both the inspiratory and expiratory flow rates were also decreased in the study group. These findings point towards adverse effects of petrol/diesel fumes mainly on lower airways with restrictive pattern of disease.

Evaluation of cognitive brain functions in caffeine users: a P3 evoked potential study.

Caffeine is one of the most widely consumed stimulant drugs of the modern world. It brings about a feeling of well-being, relaxation, increased alertness and concentration. Its effects have been studied on brain function and behavior using mood questionnaires, reaction time tests, memory tests, EEG and of late Event Related Potentials (ERPs). This study evaluates the response of caffeine on ERPs and Reaction Time (RT) using auditory "oddball" paradigm. Forty undergraduate medical students volunteered for the study and their ERPs and RT were recorded before and after 40 minutes of ingestion of caffeine. There was a non-significant decrease in latency of N1, P2, N2 and P3 and a significant decrease in Reaction Time after caffeine consumption. The amplitude of P3 showed a significant increase after intake of caffeine. The results of this study indicate that caffeine leads to facilitation of information processing and motor output response of the brain.

Effect of caffeine on central auditory pathways: an evoked potential study.

Caffeine is consumed in various forms like tea, coffee, chocolates and colas. The present study evaluated the effect of caffeine on auditory brainstem response (ABR), mid latency response (MLR) and slow vertex response (SVR) in 40 male volunteers. The recordings were done using a computerized evoked potential recorder by 10-20 electrode placement system. The subjects consumed 3mg/kg body weight of caffeine after 12h abstinence from caffeine in any form. The data obtained revealed that latencies of waves IV and V along with I-V interpeak interval of ABR decreased significantly. This was accompanied with significant increase in amplitude of wave V. MLR latencies and latency of P1 wave of SVR was significantly decreased following caffeine ingestion. The results indicated that caffeine improves transmission in the peripheral and central brain auditory pathways.

Auditory evoked potential responses in chronic malnourished children.

Auditory evoked potential responses were recorded in 20 chronic malnourished children in age group 3-6 years and in 20 healthy age and sex matched controls using an 5200 Neuropack plus ( Nihon Koden, Japan) evoked potential recorder. The absolute peak latencies, inter peak latencies and amplitude of waves I-V of brainstem auditory evoked potentials (BAEPs) were analyzed. The mid latency responses (MLRs) were also studied in these children. Malnutrition was characterized by stunting, which indicated chronicity of nutritional deprivation. The children with chronic Protein energy malnutrition (PEM) had prolonged peak latencies of waves I, II, III and IV. The interpeak latencies I-III and III-V were also prolonged. The amplitude of wave I and V did not show any significant difference as compared to controls. The middle latency responses were not significantly different from the controls. Thus malnutrition affects the peripheral developmental process of auditory pathways only in the brainstem and the central thalamocortical projections of these pathways are spared.

Pulmonary functions in air conditioner users.

Air conditioning may affect human health since it has profound effect on our environment, than just lowering temperature. The present study was planned to assess the effect of air conditioners (AC) on pulmonary functions in young healthy non-smoker males. The study group comprised of ten subjects who were using AC's in their cars for at least 1 hr daily since last 6 months. While ten subjects who did not use AC at all served as controls. The pulmonary functions were assessed using PK Morgan 232 spirometer in a closed room. The peak expiratory flow rate (PEFR) and Forced expiratory flow between 25-75% of vital capacity (FEF25-75) were significantly reduced in subjects using car AC's. Inspiratory flow rates also showed a trend towards decline in AC users but could not reach the level of significance. The lung volumes and capacities were not significantly different in the two groups except for forced expiratory volume in 0.5 sec (FEV 0.5 sec), which also decreased in AC users. The airway resistance and lung compliance did not show significant change. In the presence of normal FEV1, reduced FEF25-75% which is the flow rate over the middle half of vital capacity, is an evidence of mild airflow limitation. The result is suggestive of predisposition of AC users towards respiratory disorders in form of mild airflow restriction.

Cerebellar control of visceral responses-possible mechanisms involved.

It seems reasonable to assume that cerebellar autonomic control operates according to similar principles as those utilized in the somatomotor coordination. The unique and very uniform neuronal architecture throughout the cerebellum speaks in favour of such a view.

Functional status of auditory pathways in hypothyroidism: evoked potential study.

Hypothyroidism is known to be associated with mental retardation, motor dysfunction, memory deficits and hearing impairment. In the present study, the functional integrity of the thalamocortical projections to the primary auditory cortex and association cortex has been assessed by using Auditory Evoked Responses i.e Auditory Brainstem (ABR), Mid Latency Response (MLR) and Slow Vertex Response (SVR). Thirty newly diagnosed hypothyroid patients and thirty healthy controls were taken for the study and ABR, MLR and SVR were recorded on computerized evoked potential recorder using 10-20 system of electrode placement. The second recordings for the hypothyroid patients were done 3 months after treatment with attainment of euthyroid states. The present study revealed a slight increase in absolute latency of wave III of ABR in hypothyroid patients and significant decrease in absolute latency of wave III and interpeak latency of I-III after treatment. There was a significant decrease in amplitude of wave V in hypothyroid patients and significant increase in amplitudes of ABR wave I and wave V after treatment. There was a significant increase in latency of wave Na of MLR and wave P2 of SVR in hypothyroid patients. The latencies of waves Na, Pa, Nb of MLR and waves PI and N2 of SVR showed significant improvement with thyroid hormone treatment. The results of the present study indicates that in hypothyroid state there might be slow conduction at the periphery and with treatment there is better recruitment of neuronal pool of the generators of the waves of ABR in the brainstem. We can also conclude that the thalamocortical projections of the auditory pathways are adversely affected in the hypothyroid state and this improves after treatment.

Introducing problem-based learning in physiology in the conventional Indian medical curriculum.

BACKGROUND: Problem-based learning (PBL) is a widely acclaimed student-centred learning method. However, there are few reports of its use in the traditional lecture-practical-tutorial model of learning. We used PBL for teaching one module of Physiology to first-year medical undergraduate students who had no prior exposure to PBL. METHODS: One hundred first-year medical undergraduates enrolled in a medical college, which follows the traditional teaching-learning methods, participated in the exercise. The scheduled classes on 'Physiology of the thyroid gland' were converted into a PBL block to be covered over a week. An orientation of the teachers and students to PBL was done, clinical cases selected and tutor guides prepared before the actual PBL week. During the PBL week, students were exposed to small group discussions and Interactive resource sessions, and were given time for self-study. The PBL week concluded with a review session and evaluation of the PBL block using questionnaires. RESULTS: A comparison of the pre- and post-PBL questionnaire showed a clear preference for PBL over the conventional curriculum for the interactive resource sessions and group discussions. Both students and teachers found PBL rewarding. CONCLUSION: Implementation of PBL is feasible even in a traditional set-up despite limited resources, rigid time schedules and little interaction among various disciplines. We hope our experience would encourage other teachers to introduce appropriately modified PBL in their ongoing curriculum.

Role of yoga in modifying certain cardiovascular functions in type 2 diabetic patients.

OBJECTIVES: 1. To study the effect of forty days of Yogic exercises on cardiac functions in Type 2 Diabetics. 2. To study the effect of forty days of Yogic exercises on blood glucose level, glycosylated hemoglobin. METHODS: The present study done in twenty-four Type 2 DM cases provides metabolic and clinical evidence of improvement in glycaemic control and autonomic functions. These middle-aged subjects were type II diabetics on antihyperglycaemic and dietary regimen. Their baseline fasting and postprandial blood glucose and glycosylated Hb were monitored along with autonomic function studies. The expert gave these patients training in yoga asanas and they pursued those 30-40 min/day for 40 days under guidance. These asanas consisted of 13 well known postures, done in a sequence. After 40 days of yoga asanas regimen, the parameters were repeated. RESULTS: The results indicate that there was significant decrease in fasting blood glucose levels from basal 190.08 +/- 18.54 in mg/dl to 141.5 +/- 16.3 in mg/dl after yoga regimen. The post prandial blood glucose levels decreased from 276.54 +/- 20.62 in mg/dl to 201.75 +/- 21.24 in mg/dl, glycosylated hemoglobin showed a decrease from 9.03 +/- 0.29% to 7.83 +/- 0.53% after yoga regimen. The pulse rate, systolic and diastolic blood pressure decreased significantly (from 86.45 +/- 2.0 to 77.65 +/- 2.5 pulse/min, from 142.0 +/- 3.9 to 126.0 +/- 3.2 mm of Hg and from 86.7 +/- 2.5 mm of Hg to 75.5 +/- 2.1 mm of Hg after yoga regimen respectively). Corrected QT interval (QTc) decreased from 0.42 +/- 0.0 to 0.40 +/- 0.0. CONCLUSION: These findings suggest that better glycaemic control and stable autonomic functions can be obtained in Type 2 DM cases with yoga asanas and pranayama. The exact mechanism as to how these postures and controlled breathing interact with somato-neuro-endocrine mechanism affecting metabolic and autonomic functions remains to be worked out.

Effect of iron on growth in iron deficient anemic school going children.

Iron deficiency anemia (IDA) in children has been associated with retardation in growth and the cognitive development. In the ongoing study on the effects of IDA in school going children, the effects on anthropometric parameters such as height (Ht), Weight (Wt), head circumference (HC), body mass index (BMI) and the mid arm circumference (MAC) were studied along with the hematological parameters such as hemoglobin (Hb), hematocrit (Hct), MCV, MCH, serum iron (SI), total iron binding capacity (TIBC) and % saturation. The pre-supplementation values of all these parameters were taken in anemic and control groups of girls and boys. After deworming all the children with albendazole (400 mg), the anemic group was put on iron supplementation (Ferrous iron 3-4 mg/kg body weight/day) along with vitamin C (100 mg OD) and the control children were given vitamin C (100 mg OD), for 90 days. Pre-supplementation values of IDA children were significantly lower for MAC and HC in girls and for Ht and MAC in boys, when compared to the control group. After the therapy both the groups of girls showed improvement in the hematological parameters though it was greater in the anemic girls. Ht and Wt of both groups also improved significantly but the anemic girls showed increase in BMI also. Both the control and anemic boys showed gain in weight. Post therapy, improvement in hematological parameters for both the anemic girls and boys were greater than their respective control groups. The MAC value for anemic girls were in the control range but those of anemic boys remained lesser than the control boys. So, it can be concluded from the present study that the IDA children lagged behind the control children in terms of anthropometric parameters and they benefited relatively more in terms of anthropometric improvement and hematological improvement after iron supplementation.

Auditory evoked responses in gestational diabetics.

Electrophysiological correlates of sensory function in diabetic pregnancy have not been documented. Present study reports changes in Auditory evoked responses (AER) in gestational diabetics when compared with normal pregnant controls. Human AER are generally classified into early Auditory brainstem responses (AER), Mid latency responses (MLR) and late Slow vertex responses (SVR). These potentials were recorded in 20 women with diabetic pregnancy using Ag/AgCl electrodes from Cz-A1 and Cz-A2 position on MEB 5200 Neuropack II ... plus (Nihon Kohden, Japan) Evoked Potential Recorder. The evoked potentials in gestational diabetics were compared with 20 age matched normal pregnant women using Student's t-test. Absolute latencies of waves I to V, Inter peak latencies I-III and I-V of ABR were significantly increased whereas amplitude of wave V decreased in diabetic pregnant women. No significant change in latency of any component of MLR was observed between the two groups whereas significant prolongation of latencies of all components of SVR was observed in diabetic pregnant women as compared to normal control group. These findings indicate prolongation of both peripheral transmission time (PTT) and central transmission time (CTT) in diabetic pregnant females. Prolongation of latencies of SVR components in this study implicates cortex in the central diabetic neuropathy in women with gestational diabetes.

Correlation of autonomic indices with thyroid status.

The autonomic status in female thyroid patients was compared with healthy, age matched normal females taken as controls. The patients (29 +/- 7 years) were categorised into two groups: hyperthyroid and hypothyroid. The valsalva manoeuvre, standing to lying ratio (S/L ratio) and immediate heart rate response to standing (30:15 ratio) to assess the parasympathetic status while the galvanic skin response (GSR) was recorded to assess the sympathetic status. Statistical analysis was done using Student's t-test for comparing between the different groups and regression analysis were performed between autonomic indices and thyroid hormone levels. Although the mean values were not significantly different in hypothyroid and hyperthyroid patients, yet the correlation between autonomic function and thyroid hormone levels indicates a statistically significant difference (P-value<0.05), with the S/L ratio. The correlation was negative for log [T3] and log [T4], while it was positive for log [TSH]. This indicates that there is decreased parasympathetic activity with increased T3 and T4, which is in agreement earlier reports. The GSR, which is one of the measures of sympathetic activity, was found to be unaffected.

Long latency auditory evoked responses in ovulatory and anovulatory menstrual cycle.

Central nervous system pathways get influenced by the changing hormonal levels across the menstrual cycle. In an effort to see the effects on the conduction in central auditory pathways we recorded long latency auditory evoked potentials (LLAEPs) across the 4 different phases of the menstrual cycle. 20 females having normal ovulatory menstrual cycles were tested 4 times in a single cycle and LLAEPs were recorded from Cz-A1 and Cz-A2 position with alternating 90 dB sound pressure click stimuli. Twenty age matched control females having anovulatory menstrual cycles were also tested on the corresponding days. All control females were taking oral contraceptive (O.C.) pills. The LLAEPs were compared inter-group wise as well as inter-phase wise for each parameter by using hierarchal ANOVA design and Tukey test was applied to find out the significance level. Peak latencies of waves P2 and N2 were found to be delayed during mid-cycle and relatively reduced mid-luteal phase in ovulatory menstrual cycles. No such response was noticed in oral contraceptive using group. This indicates that normal cyclic variations of female sex hormones especially estrogen and progesterone modify the central processing of the auditory information. Estrogen may be responsible for delaying the conduction by influencing GABA release at the level of polysensory association areas of the brain.

Auditory evoked responses in postmenopausal women on hormone replacement therapy.

The effect of hormone replacement therapy (HRT) was studied in 32 postmenopausal women on their auditory Evoked Potentials i.e. auditory brainstem response (ABR), Middle latency response (MLR) & slow vertex response (SVR). Recordings were done on computerized evoked potential recorder using 10/20 system of electrode placement and standard click stimuli. A significant improvement in neural transmission was observed as was evidenced by decrease in the ABR wave latencies I, III, IV & V and interpeak latency III-V and I-V after 6 months of HRT. A similar significant decrease was observed in MLR wave latencies of Po, Na & Pa. The SVR wave latencies although found to be decreased after HRT, could not reach the level of statistical significance. There was a significant inverse correlation obtained between latencies of wave I in ABR, Po in MLR and serum estradiol. The results indicate the effect of sex hormone in improving transmission in auditory pathway from periphery through brainstem, thalamus upto cortex. However slow vertex responses indicate that auditory association areas are not much affected. This might have bearing on improvement of neuropsychological functions in postmenopausal women on HRT.