Biomedical subjects
K Chopra
Publications and source records attributed to K Chopra.
A study of neonatal diarrhoea.
Explore the source record for details and available documents.
Perinatal and neonatal mortality and morbidity in the hospital born babies.
Explore the source record for details and available documents.
Multi drug resistant tuberculosis.
Explore the source record for details and available documents.
Rhabdomyolysis.
Rhabdomyolysis is a condition caused by skeletal muscle injury and release of muscle cell contents into the circulation. It may result in myoglobinuria, the filtration of myoglobin into the urine, and is often associated with acute renal failure (ARF). Rhabdomyolysis may complicate many disease states. In some, such as crush injury, muscle injury is obvious; in others, such as drug overdose, it may never be apparent. It may occur in the setting of an altered mental status, and even in the conscious patient, it may occur with minimal symptoms or physical findings. Therefore, diagnosis requires a high level of suspicion and appropriate sensitivity to abnormal laboratory values. Many insults can precipitate rhabdomyolysis and myoglobinuria. Disruption of the muscle cell membrane may result from a direct mechanical or toxic insult to the membrane or an inability to maintain ionic gradients across the membrane (as in ischemia or extreme exertion). This article reviews the etiology, pathogenesis, clinical features, complications, and management of rhabdomyolysis, particularly crush injuries in the setting of a major disaster.
Pyopneumothorax associated with pneumopericardium.
An unusual association of pneumopericardium with pyopneumothorax is presented. Pneumopericardium responded after intercostal drainage.
Benzodiazepine inverse agonist FG-7142-induced delayed behavioral depression in mice.
Effect of acute administration of a benzodiazepine-inverse agonist, FG-7142, on forced swimming-induced depression was investigated in mice. A single injection of FG-7142 (40 mg/kg) showed a delayed increase in behavioral despair, the peak effect being observed on the 5th and 6th day of FG-7142 administration. beta-Adrenoceptor agonist isoprenaline significantly potentiated FG-7142-induced behavioral despair. FG-7142-induced depression was sensitive to reversal by chronic treatment with propranolol or desipramine. These observations suggest that the inverse agonist FG-7142 upregulates beta-adrenoceptor population leading to behavioral despair in mice.
Potentiation of dopamine receptor-mediated responses by B-HT 920 in mice.
The effect of B-HT 920, an alpha 2-agonist, on postsynaptic dopamine receptor-mediated stereotypic behaviour, was studied in mice. Apomorphine produced typical stereotypic responses in mice such as sniffing, rearing, biting, licking and grooming. B-HT 920, when given alone, produced mild stereotypy. Pretreatment with B-HT 920 significantly potentiated the stereotypic behaviour of apomorphine. The specific alpha 2-blockers, idazoxan and yohimbine, failed to block the potentiating effect of B-HT 920. The specific D2-receptor blockers haloperidol and molindone, completely blocked the stereotypic responses due to B-HT 920 and apomorphine. On reserpinization of animals there was a 5-fold increase in stereotypy induced by the combination of apomorphine and B-HT 920. B-HT 920 also potentiated amphetamine-induced locomotor responses in mice in a haloperidol-sensitive way. These data imply an interaction of B-HT 920 with postsynaptic dopamine receptors.
Role of percutaneous needle biopsy by Cope's needle in the diagnosis of pleural diseases.
Explore the source record for details and available documents.
Mediastinal space occupying lesions--a ten-year experience of forty-four cases with review of literature.
Explore the source record for details and available documents.
Serum immunoglobulins in cases of pulmonary tuberculosis.
Explore the source record for details and available documents.
Oxygen free radicals and protective effect of captopril on myocardial infarct size.
Captopril (0.25 mg/kg and 0.5 mg/kg, p.o.) decreased the myocardial infarct size and prevented the progressive decrease in voltage of the R wave in rats. It had no marked effect on systolic blood pressure at these dose levels but higher doses (1 mg/kg, p.o.) reduced systolic blood pressure. It also produced a concentration-dependent (50-700 ng/10(6) cells) decrease of chemiluminescence response from rat neutrophils and markedly reduced serum malonyldialdehyde levels, elevated as a consequence of left coronary artery ligation. It is suggested that the protective effect of captopril may be mediated through a decreased formation or scavenging of reactive oxygen species.
Effect of 7-oxo-PGI2 on myocardial infarct size and role of oxygen radicals in its protective effect.
The ability of the prostacyclin analogue 7-oxo-PGI2 to inhibit infarct size in in vivo rat heart was assessed. Anaesthetized rats were subjected to coronary artery ligation for 72 hours and infarct size was measured macroscopically using staining with triphenyl tetrazolium chloride. Systolic blood pressure and electrocardiogram were monitored. 7-oxo-PGI2 (50 micrograms/kg, i.p.), administered 30 minutes before or after coronary artery ligation, markedly reduced infarct size and loss of R wave. It did not, however, influence the changes of systolic blood pressure and heart rate in these animals. In addition, 7-oxo-PGI2, both in vitro and in vivo, inhibited rat PMN-evoked and luminol-enhanced chemiluminescence and markedly reduced the increase in serum malonyldialdehyde levels occurring after coronary artery ligation. The capacity of 7-oxo-PGI2 to impair the generation of oxygen free radicals from PMN cells, which reach the site of ischaemic injury through the limited collateral flow available in rat myocardium, may be responsible for its beneficial effect on ischaemic myocardial injury.