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O P Tandon

Publications and source records attributed to O P Tandon.

At least 19 recordsLinked to original sources
PubMed2006

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.

Adolescent↗
PubMed2004

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.

Adult↗
PubMed2003

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.

Anemia, Iron-Deficiency↗
PubMed2003

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.

Adolescent↗
PubMed2003

Neurophysiology of pain: insight to orofacial pain.

This is a very exciting time in the field of pain research. Major advances are made at every level of analysis from development to neural plasticity in the adult and from the transduction of a noxious stimulus in a primary afferent neuron to the impact of this stimulus on cortical circuitry. The molecular identity of nociceptors, their stimulus transduction processes and the ion channels involved in the generation, modulation and propagation of action potentials along the axons in which these nociceptors are present are being vigorously perused. Similarly tremendous progress has occurred in the identification of the receptors, transmitters, second messenger systems, transcription factors, and signaling molecules underlying the neural plasticity observed in the spinal cord and brainstem after tissue or nerve injury. With recent insight into the pharmacology of different neural circuits, the importance of descending modulatory systems in the response of the nervous system to persistent pain after injury is being reevaluated. Finally, imaging studies revealed that information about tissue damage is distributed at multiple forebrain sites involved in attentional, motivational, and cognitive aspects of the pain experience.

Animals↗
PubMed2003

Effects of iron therapy on cognition in anemic school going boys.

The present study was conducted on 18 anemic and 34 control subjects (mean age 9.26 +/- 0.26 years) to observe the effect of anemia on cognition and to see effect of 3 months of iron therapy on it. Anemia was defined on the basis of hematological values and peripheral smear examinations. Cognitive data consisted of the recording of the P300 wave of Auditory Event Related Potentials (AERP), Ravens Progressive Matrices Test (RPMT), and Digit Span Attention Test (DSAT) under standard test conditions. RPMT scores were then converted to the intelligence quotient (IQ) scores for comparison. Both anemic and control boys were dewormed after recording pretreatment values and then anemic boys were given iron therapy for 3 months, after which the recordings were taken again. Pretreatment, anemic boys showed significantly lower hematological values, delayed P300 latency, and lower RPMT scores as compared to controls. Post therapy the hematological profile of anemic boys though significantly improved as compared to the pretreatment values, was still significantly lower than that of control boys. The P300 latency values of anemic boys showed improvement but were still significantly delayed than the control group. RPMT values and derived IQ scores of anemic boys were similar to control boys after therapy suggesting that though the 3 months iron therapy regime resulted in improvement in psychometric cognitive tests in anemic boys, the basic P300 defects persisted. This suggests that the P300 component of AERP in anemic children is relatively refractory to 3 months of iron therapy.

Anemia↗
PubMed2003

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.

Adult↗
PubMed2003

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.

Acoustic Stimulation↗
PubMed2003

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.

Acoustic Stimulation↗
PubMed2003

Mid latency and slow vertex responses during pregnancy.

Central auditory pathways picked up electro-physiologically as mid latency responses (MLRs) and slow vertex responses (SVRs) have been studied least in women during their critical periods of life although auditory brainstem responses (ABRs) have been studied by many researchers. In the present study MLRs and SVRs were recorded in 20 pregnant women of age group 18-28 years. Their period of gestation ranged between 26-40 weeks and pregnancy had been uneventful and normal. MLRs and SVRs were recorded from Cz-A1 and Cz-A2 positions with alternating 90 dB sound pressure click stimuli delivered at 5 Hz and 0.5 Hz respectively. 256 stimuli for mid-latency and 64 stimuli for slow vertex responses were averaged and analyzed. Different waves of these auditory evoked responses were compared with 20 age matched non-pregnant females. The data obtained was analyzed for each variable by using unpaired student's T test. Present study did not reveal any difference in MLR waves during pregnancy when compared with the non-pregnant females whereas all the SVR waves were found to be significantly delayed in pregnant females. As SVR generators are found in different cortical areas, it can be said that auditory information processing at the higher centers is slow during pregnancy which in turn could be due to elevated levels of sex hormones specially estrogen and progesterone during pregnancy.

Acoustic Stimulation↗
PubMed2003

Lipid peroxidation and antioxidant enzymes in gestational diabetics.

The exact pro-oxidant and antioxidant status in gestational diabetes is still unclear. To add new insight to the question, changes in the lipid peroxidation products (MDA) and activities of antioxidant enzymes: superoxide dismutase (SOD) and catalase in red blood cell hemolysates were evaluated in 20 women with gestational diabetes. 20 healthy pregnant women served as the control group. Statistical analysis was done using unpaired Student' t - test. Pregnant women with gestational diabetes showed an increase in lipoperoxidation products (P < 0.001) and a decrease in SOD activity (P < 0.01) as compared to normal pregnant women while no significant change was observed in catalase activity. These findings suggest increased oxidative stress and decreased detoxification or free radical scavenging capacity in pregnancy complicated by diabetes.

Adult↗
PubMed2002

Event related evoked potentials in dementia: role of vitamin E.

Dementia is a common cognitive syndrome reflecting a wide spread chronic progressive disease as an extension to normal aging process. Oxidative stress has been implicated in dementia and antioxidants have become attractive therapeutic agents. Among the antioxidants vitamin E is the most potent in the treatment of dementia. Study was conducted in 20 patients suffering from dementia in the age group of 66-74 and in 20 age and sex matched controls. Latency of the P3 component of event related evoked potential (ERP) showed an increase from 338.65 +/- 42.22 msec in control group to 348.9 +/- 46.38 msec in patients of dementia. In control group P3 latency decreased from 338.65 +/- 42.22 msec to 331.6 +/- 38.75 msec after Vitamin E therapy. In patients of dementia latency decreased significantly from 348.9 +/- 46.38 msec to 324.62 +/- 44.25 msec after vitamin therapy for one month. P3 amplitude in controls and demented was 7.2 +/- 3.62 mu v and 7.07 +/- 3.73 mu v respectively. After vitamin E therapy a statistically significant increase in amplitude (P < 0.05) was observed in controls (9.34 +/- 5.04 mu v) and in patients of dementia (9.58 +/- 5.24 mu v). The study suggests that the latency and amplitude of P3 were not significantly different in control and dementia patients, while vitamin E supplementation (oral 800 mg per day for 30 days) decreased the latency and increased the P3 amplitude in both the control and dementia patients. Our study further supports that Vitamin E supplementation, because of its antioxidant property might be decreasing oxidative stress, which may lead to improvement in cognitive pool of generator neurons of P3.

Aged↗
PubMed2002

Effect of Yoga asanas on nerve conduction in type 2 diabetes.

Twenty Type 2 diabetic subjects between the age group of 30-60 years were studied to see the effect of 40 days of Yoga asanas on the nerve conduction velocity. The duration of diabetes ranged from 0-10 years. Subject suffering from cardiac, renal and proliferative retinal complications were excluded from the study Yoga asanas included Suryanamskar. Tadasan, Konasan, Padmasan Pranayam, Paschimottansan Ardhmatsyendrasan, Shavasan, Pavanmukthasan, Sarpasan and Shavasan. Subjects were called to the cardio-respiratory laboratory in the morning time and were given training by the Yoga expert. The Yoga exercises were performed for 30-40 minutes every day for 40 days in the above sequence. The subjects were prescribed certain medicines and diet. The basal blood glucose, nerve conduction velocity of the median nerve was measured and repeated after 40 days of Yogic regime. Another group of 20 Type 2 diabetes subjects of comparable age and severity, called the control group, were kept on prescribed medication and light physical exercises like walking. Their basal & post 40 days parameters were recorded for comparison. Right hand and left hand median nerve conduction velocity increased from 52.81 +/- 1.1 m/sec to 53.87 +/- 1.1 m/sec and 52.46 +/- 1.0 to 54.75 +/- 1/1 m/sec respectively. Control group nerve function parameters deteriorated over the period of study, indicating that diabetes is a slowly progressive disease involving the nerves. Yoga asanas have a beneficial effect on glycaemic control and improve nerve function in mild to moderate Type 2 diabetes with sub-clinical neuropathy.

Adult↗
PubMed2002

Study of yoga asanas in assessment of pulmonary function in NIDDM patients.

Certain yoga asanas if practiced regularly are known to have beneficial effects on human body. These yoga practices might be interacting with various, somato-neuro-endocrine mechanisms to have therapeutic effects. The present study done in twenty four NIDDM patients of 30 to 60 year old, provides metabolic and clinical evidence of improvement in glycaemic control and pulmonary 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 pulmonary function studies. The expert gave these patients training in yoga asanas and were pursed 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. The results indicate that there was significant decrease in fasting blood glucose levels (basal 190.08 +/- 90.8 in mg/dl to 141.5 +/- 79.8 in mg/dl). The postprandial blood glucose levels also decreased (276.54 +/- 101.0 in mg/dl to 201.75 +/- 104.1 in mg/dl), glycosylated hemoglobin showed a decrease (9.03 +/- 1.4% to 7.83 +/- 2.6%). The FEV1, FVC, PEFR, MVV increased significantly (1.81 +/- 0.4 lt to 2.08 +/- 0.4 lt, 2.20 +/- 0.6 lt to 2.37 +/- 0.5 lt, 3.30 +/- 1.0 lt/s to 4.43 +/- 1.4 lt/s and 64.59 +/- 25.7 lt min to 76.28 +/- 28.1 lt/min respectively). FEV1/FVC% improved (85 +/- 0.2% to 89 +/- 0.1%). These findings suggest that better glycaemic control and pulmonary functions can be obtained in NIDDM 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 pulmonary functions remains to be worked out.

Adult↗
PubMed2002

Effect of partial ileal bypass on the lipid profile in the hyperlipedemic rabbits.

The hypocholesterolemic effect of partial ideal bypass was studied in two groups of healthy albino rabbits. Both groups of rabbits were made hypercholesterolemic by feeding them cholesterol suspended in groundnut oil (1 ml/kg bw) at a dose of 100 ml/kg bw/day for one week. Group I rabbits were subjected to partial ileal bypass and group II rabbits were sham operated. Weekly estimation of serum lipid profiles were done for four more weeks while continuing cholesterol feed. After end of 5th week, it was found that partial ileal bypass not only prevented but also brought down its level from 132.8 mg% to 44.8 + 2.24 mg%, as compared to sham operates group where cholesterol level was 279 + 5.84 mg%. There was improvement in other parameters of lipid profiles namely HDL-C & LDL-C + VLDL-C and TAG.

Animals↗
PubMed2002

Pain measurement: a formidable task.

Pain is defined as unpleasant sensory and emotional experience, associated with actual or impending tissue damage. It consists of multi-dimentional phenomenon having sensory discriminative, cognitive-evaluative and effective motivational components. Though the technology has advanced, still it is very difficult to objectively assess all the attributes of pain, including alteration in cognitive behaviour. However, subjective methods like Visual Analog Scale rating (VAS) and preliminary objective methods like pain evoked responses, behaviral monitoring and event related evoked potentials for cognition are currently in vogue. It will take some more time and effort to evolve yet other newer and sophisticated techniques to measure all aspects of pain in human beings.

Animals↗
PubMed2002

Auditory evoked responses during different phases of menstrual cycle.

The electrophysiological correlates of changes in sensory function during menstrual cycle has already been studied and attributed to the hormonal influence. Effects of estrogen and progesterone on waves of auditory brainstem responses (ABR) have been reported and a hypothesis has been proposed that sex steroids have more influence on central auditory pathways. As mid-latency responses (MLRs) and slow vertex responses (SVRs) are better indicators of central auditory pathways, so MLRs and SVRs were also recorded besides ABRs in the present study. Waves of ABRs, MLRs & SVRs were recorded in 20 normal cycling females in 4 different phases of menstrual cycles from Cz-A1 and Cz-A2 position with alternating 90dB sound pressure click stimuli. Contralateral ear was masked with a white noise of -40 dBHL. With the same setting by changing the number of click stimuli, intervals of stimuli and filter bandpass the above 3 recordings were taken. The evoked responses in females having ovulatory cycles were compared within the four phases using ANOVA test. There is a trend of increase in peak latencies of ABR waves III and V and IPL I-V in estrogen-peak midcycle while decrease in latencies in progesterone-peak (interpeak latency) midluteal phase. Peak latencies of MLR waves No, Po, Na, Pa and Pb also show a same trend. SVR waves P2 and N2 are significantly delayed in mid-cycle (178.80 +/- 20.49, 276.65 +/- 18.32) while conduction is faster in midluteal phase (166.45 +/- 17.41, 261.95 +/- 21.07). Smallest latencies of all the waves are occurring during menstruation. These findings are suggesting that normal cyclical variations in the levels of estrogen and progesterone during menstrual cycle do affect the auditory pathways and effects are better seen on the central component.

Acoustic Stimulation↗