PubMed Health⌕ Search

Biomedical subjects

Indu Taneja

Publications and source records attributed to Indu Taneja.

8 recordsLinked to original sources
PubMed2007

A randomized, double-blind, crossover trial of modafinil on mood.

Modafinil, a medication for the excessive sleepiness associated with narcolepsy, has been hypothesized to improve not just alertness but mood as well. The purpose of this study was to determine how treatment with modafinil affects mood in healthy volunteers. Normal healthy volunteers (n = 12, 10 men and 2 women; 30-44 years) underwent a 3-day, counterbalanced, randomized, crossover, inpatient trial of modafinil (400 mg daily) versus placebo with 4-day washout period between 2 treatments. Mood was assessed daily using both the Positive and Negative Affect Schedule and a general mood scale, which consisted of 10 bipolar adjective ratings based on a severity scale ranging from 1 to 10. Modafinil increased general mood and Negative Affect scales relative to placebo and had a significant effect on Positive Affect scales. These results suggest that modafinil may have general mood-elevating effects accompanied by increased negative affect (anxiety). The findings may have implications for clinical practice, in particular for the adjunctive use of modafinil in treatment-resistant depression.

Administration, Oral↗
PubMed2006

Differential effects of lower body negative pressure and upright tilt on splanchnic blood volume.

Upright posture and lower body negative pressure (LBNP) both induce reductions in central blood volume. However, regional circulatory responses to postural changes and LBNP may differ. Therefore, we studied regional blood flow and blood volume changes in 10 healthy subjects undergoing graded lower-body negative pressure (-10 to -50 mmHg) and 8 subjects undergoing incremental head-up tilt (HUT; 20 degrees , 40 degrees , and 70 degrees ) on separate days. We continuously measured blood pressure (BP), heart rate, and regional blood volumes and blood flows in the thoracic, splanchnic, pelvic, and leg segments by impedance plethysmography and calculated regional arterial resistances. Neither LBNP nor HUT altered systolic BP, whereas pulse pressure decreased significantly. Blood flow decreased in all segments, whereas peripheral resistances uniformly and significantly increased with both HUT and LBNP. Thoracic volume decreased while pelvic and leg volumes increased with HUT and LBNP. However, splanchnic volume changes were directionally opposite with stepwise decreases in splanchnic volume with LBNP and stepwise increases in splanchnic volume during HUT. Splanchnic emptying in LBNP models regional vascular changes during hemorrhage. Splanchnic filling may limit the ability of the splanchnic bed to respond to thoracic hypovolemia during upright posture.

Adolescent↗
PubMed2006

Sodium paradoxically reduces the gastropressor response in patients with orthostatic hypotension.

Orthostatic hypotension (OH) can cause syncope that is difficult to treat. We have found that 473 mL (16 oz) of water can increase systolic blood pressure (SBP) by > 30 mm Hg in many OH patients (the gastropressor response). OH patients are routinely advised to increase their sodium intake to augment their blood volume. We tested the hypothesis that the ingestion of salt with water would increase the magnitude of the acute pressor response compared with water alone in patients with OH. Patients with OH (n = 9; female = 5; 65+/-3 years) underwent a randomized crossover trial of drinking water (H2O) and salt water (NaCl-H2O). Noninvasive heart rate and BP were measured with the patient seated for > or = 60 minutes after ingestion. The area under the curve for SBP was greater with H2O than NaCl-H2O for the 30 minutes (714+/-388 mm Hg x min versus 364+/-369 mm Hg x min; P = 0.002) and 60 minutes (1454+/-827 mm Hg x min versus 812+/-734 mm Hg x min; P = 0.048) after ingestion. The increase in SBP with H2O was greater than with NaCl-H2O at 30 minutes (37+/-6 versus 18+/-5 mm Hg; P = 0.006) but not at 60 minutes (17+/-6 versus 10+/-6 mm Hg; P = 0.4). Norepinephrine increased after H2O (P = 0.018) but not after NaCl-H2O (P = 0.195). Both oral water and salt water increase BP in patients with OH. Instead of augmenting the gastropressor response, the additional salt paradoxically attenuates the pressor response to water. These data suggest a potentially important role for gastrointestinal osmolality in the activation of the sympathetic nervous system leading to cardiovascular reflexes responsible for the gastropressor response.

Aged↗
PubMed2005

Modafinil elicits sympathomedullary activation.

The autonomic effects of modafinil (Provigil), a psychostimulant widely used to attenuate fatigue and promote wakefulness, are currently unexplored. We assessed the effect of modafinil on autonomic nervous system. We compared oral modafinil (400 mgx1) versus placebo in 12 healthy hospitalized normal subjects in a randomized double-blind, placebo-controlled cross-over study for 3 days each with subjects in 150 mEq sodium, 70 mEq potassium balance at the Vanderbilt General Clinical Research Center. Modafinil increased resting heart rate (9.2+/-2.0 bpm; mean [+/-SE]; 95% confidence interval [CI], 4.7 to 13.6; P=0.001), resting systolic blood pressure (7.3+/-3.2 mm Hg; 95% CI, 0.2 to 14.4; P=0.044), and resting diastolic blood pressure (5.3+/-1.7 mm Hg; 95% CI, 1.4 to 9.1 mm Hg; P<0.012). Modafinil elicited a 42% higher orthostatic increase in plasma norepinephrine (0.8+/-0.3 nmol/L; 95% CI, 0.2 to 1.3; P=0.01), and caused a 33% increase in urine norepinephrine (5.1+/-1.1 nmol/L creatinine per day; 95% CI, 2.7 to 7.4, P=0.001), and an 81% increase in urine epinephrine (1.3+/-0.2 nmol/L creatinine per day; 95% CI, 1 to 2; P<0.001). The peroneal microneurographic sympathetic activity was attenuated by modafinil during orthostatic tilt (P<0.001). alpha1-Adrenoreceptor function was maintained. Modafinil substantially perturbs autonomic cardiovascular regulation by increase in heart rate and blood pressure. Autonomic changes of this magnitude encourage caution in use of modafinil in patients with cardiovascular disease.

Adrenal Medulla↗
PubMed2004

Yogic versus conventional treatment in diarrhea-predominant irritable bowel syndrome: a randomized control study.

This study was conducted to evaluate the comparative effect of yogic and conventional treatment in diarrhea-predominant irritable bowel syndrome (IBS) in a randomized control design. The patients were 22 males, aged 20-50 years, with confirmed diagnosis of diarrhea-predominant IBS. The conventional group (n = 12, 1 dropout) was given symptomatic treatment with loperamide 2-6 mg/day for 2 months, and the yogic intervention group (n = 9) consisted of a set of 12 asanas (yogic poses, i.e., Vajrasana, Shashankasana, Ushtrasana, Marjariasana, Padhastasana, Dhanurasana, Trikonasana in two variations, Pawanmuktasana, and Paschimottanasana) along with Surya Nadi pranayama (right-nostril breathing) two times a day for 2 months. All participants were tested at three regular intervals, at the start of study--0 month, 1 month, and 2 months of receiving the intervention--and were investigated for bowel symptoms, autonomic symptoms, autonomic reactivity (battery of five standard tests), surface electrogastrography, anxiety profile by Spielberger's Self Evaluation Questionnaire, which evaluated trait and state anxiety. Two months of both conventional and yogic intervention showed a significant decrease of bowel symptoms and state anxiety. This was accompanied by an increase in electrophysiologically recorded gastric activity in the conventional intervention group and enhanced parasympathetic reactivity, as measured by heart rate parameters, in yogic intervention group. The study indicates a beneficial effect of yogic intervention over conventional treatment in diarrhea-predominant IBS.

Adult↗
PubMed2004

Aortic stenosis and autonomic dysfunction: co-conspirators in syncope.

Autonomic dysfunction and aortic stenosis share several clinical characteristics, including, in severe cases, syncope. Both illnesses tend to manifest later in life, and most cases are idiopathic in origin. In a short period of 4 weeks, the authors noted that three patients out of 36 referrals for autonomic dysfunction also had histories of aortic valve replacement due to stenosis. In each case, similar presenting symptoms of fatigue, light-headedness, and syncope were attributed to aortic stenosis without mention of autonomic failure as a possible contributor. The authors propose that patients for whom symptoms of aortic valve stenosis are not relieved by surgical intervention may have concomitant autonomic dysfunction contributing significantly to their symptoms. Furthermore, the two conditions may comprise a dangerous combination, aortic stenosis causing physical obstruction of ventricular outflow, and autonomic dysfunction causing decreased venous return and insufficient cardiac filling. It may be beneficial for patients with aortic stenosis who present with syncope to be considered for possible autonomic dysfunction to address both potential pathophysiologies contributing to the syncope.

Aged↗
PubMed2003

Genetic basis of autonomic dysfunction.

The human genome has become a roadmap for elucidation of the pathophysiology of disease. It is likely that mutations in more than 1000 of the approximately 30,000 human genes will lead to autonomic abnormalities, either directly or indirectly. This review highlights some of these, which exert major effects on catecholamine metabolism and relate specific catecholaminergic phenotypes to neurogenetic disorders. Distinctive catecholamine patterns in several neurogenetic conditions may reflect direct or indirect effects of gene mutations. These neurochemical patterns can provide potentially important clues to the diagnosis, treatment, and pathophysiology of neurogenetic disorders.

Animals↗