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Biomedical subjects

S K Dwivedi

Publications and source records attributed to S K Dwivedi.

At least 37 records · Page 2Linked to original sources
PubMed1995

In vitro and in vivo antitrypanosomal activity of Xanthium strumarium leaves.

Antitrypanosomal activity of crude 50% ethanolic extract of Xanthium strumarium leaves was studied in vitro and in vivo. The extract exhibited trypanocidal activity at all four concentrations tested i.e. 5, 50, 500 and 1000 micrograms/ml, in vitro. In vivo trial revealed that the extract exerted antitrypanosomal effect at dosage of 100, 300 and 1000 mg/kg, intraperitoneally. At 100 and 300 mg/kg doses the survival period of the Trypanosoma evansi infected mice was significantly prolonged. However, the extract was found to be toxic to the animals at 1000 mg/kg dose.

Animals↗
PubMed1995

The effect of concurrent lead and cadmium exposure on the cell-mediated immune response in goats.

Cell-mediated immune response was monitored by cutaneous hypersensitivity reaction (CHR) to 2-4 dinitrochlorobenzene in goats given lead or cadmium alone or in combination. Twenty goats were divided into 4 groups of 5 animals each. Group A served as control whereas Groups B, C and D were given po doses of 50 mg lead acetate/kg body weight, 10 mg cadmium chloride/kg body weight or 50 mg lead acetate/kg body weight + 10 mg cadmium chloride/kg body weight, respectively, for 42 d. Primary sensitization was done on day 27 followed by a challenge dose after 14 d. Elicitation of CHR, as measured by average increase in skin thickness, was suppressed significantly in goats of all dosed groups. Suppression was more in the cadmium-dosed than in the lead or lead + cadmium dosed goats. Histopathology demonstrated reduced intensity of cellular reactions in the cadmium and lead + cadmium-dosed animals.

Animals↗
PubMed1995

Lead in blood and milk from urban Indian cattle and buffalo.

Lead levels were estimated in blood and milk collected from cattle and buffalo in 3 urban areas in India. Mean blood lead concentrations were above background levels. The highest mean blood lead was from Delhi/Ghaziabad (0.43 +/- 0.06) where 11.11% of the samples contained 0.80 ppm lead. Mean milk lead concentrations were 0.28 +/- 0.06 ppm in Ahmedabad, 0.28 +/- 0.05 ppm in Calcutta and 0.27 +/- 0.05 ppm in Delhi. More than 50% of the milk samples from these areas had higher lead concentrations than the background levels suggested for milk.

Animals↗
PubMed1995

In vitro and in vivo therapeutic activity of Parthenium hysterophorus against Trypanosoma evansi.

Crude 50% ethanolic extract of P. hysterophorus flowers exhibited trypanocidal activity in vitro at all the four concentrations tested i.e. 5, 50, 500 and 1000 micrograms/ml. In vivo trial revealed that the extract exerted antitrypanosomal effect at doses of 100 and 300 mg/kg body wt, i.p. as evidenced by significantly reduced (P < 0.01) mean parasitaemia on days 3, 4, 5 and 6 when compared with untreated control group. Further at 100 and 300 mg/kg, body wt doses, the survival period was significantly (P < 0.05) prolonged as compared to control group. The extract was, however, found toxic to the animals at 1000 mg/kg dose.

Animals↗
PubMed1992

Estimation of elastic recovery, work of decompression and Young's modulus using a rotary tablet press.

Capping and lamination occur when the bonds within a tablet cannot withstand the elastic recovery during decompression. To estimate tablet recovery, it is necessary to subtract the machine recovery from the total recovery during decompression. A direct relationship between the force and machine deformation is applied in a novel fashion to calculate in-die tablet recovery on a Manesty Betapress and to estimate the Young's modulus, E, of various solids from the recovery data. The E values of about twenty-five pharmaceutical solids were found to be in reasonable agreement with literature values. This procedure allows in-process analysis of tablet recovery and gives E without the use of specialized equipment.

Algorithms↗
PubMed1991

Biochemical alterations in serum and cerebrospinal fluid in experimental acidosis in goats.

Experimental acidosis was induced in six goats aged between one and two years by administration of whole wheat grain at 100 g kg-1 bodyweight given intraruminally. Blood and cerebrospinal fluid (CSF) samples were collected from these goats before administration of wheat grain (0 hour) and thereafter at 12, 24, 48, 72, 96 and 120 hour intervals. These were analysed for serum enzyme activities and physicochemical characters of CSF. Significantly (P less than 0.05) higher activities of amylase (at 12 hours), lactate dehydrogenase (12 to 48 hours), creatine phosphokinase (12 to 48 hours), aspartate aminotransferase (12 to 24 hours), and gamma-glutamyl transferase (12 to 96 hours) were found in serum samples of acidotic goats. Changes in CSF included decrease of pH and chloride content and higher glucose values. No difference was seen in the physical character of CSF collected at different time intervals from acidotic goats.

Acidosis↗
PubMed1991

Peak offset times as an indication of stress relaxation during tableting on a rotary tablet press.

During powder compaction on a Manesty Betapress, peak pressures, Pmax, are reached before the punches are vertically aligned with the centres of the upper and lower compression roll support pins. The interval between the time taken to reach this alignment and the time to reach Pmax is defined as the peak offset time, t(off). The duration of t(off) depends on the ability of the compacted powder to relieve stress and is an indication of the predominant mechanisms of particle deformation during consolidation. Thus, at a given Pmax, short t(off) values are characteristic of materials that consolidate mainly by brittle fracture while longer values indicate an increase in plastic flow. On the Betapress, the decrease in stress during t(off) occurs under conditions approaching constant strain and t(off) therefore, is an indirect measure of stress relaxation. Stress relaxation, and hence t(off), decreases with increase in Pmax due to the reduction in the porosity of the compact and consequent restriction of plastic flow into the void spaces. In addition to Pmax, the effects of variables such as punch head geometry, press speed and formulation on t(off) are reported.

Acetaminophen↗
PubMed1990

Diagnostic use of blood porphyrin and radiographic changes in lead exposure in goats.

Blood porphyrin, hematological examination and radiographic changes were evaluated for the detection of lead intoxication in goats given daily po doses of 10, 15 and 20 mg lead acetate (5.43, 8.15 and 10.86 mg lead)/kg body weight for 30, 30 and 31 days, or a total of 91 days. Blood porphyrin was found a sensitive indicator with direct correlation (r = 0.976) to blood lead concentration. Basophilic stippling was not seen in the lead-exposed goats. Radiopaque bands developed at the distal metaphysis of the radius in 7 of the 12 lead-exposed goats at day 30. The usefulness of this sign for the diagnosis of lead exposure in goats requires further investigation.

Animals↗
PubMedDate not supplied

Accelerated infusion of streptokinase in acute myocardial infarction results in better TIMI flow grade in infarct-related artery.

Bolus followed by rapid infusion of tissue plasminogen activator results in higher grade of TIMI flow in infarct-related artery as compared to slow infusion. In the present study, an accelerated regimen of streptokinase given over 15 minutes was compared with conventional infusion over one hour in 47 patients presenting within 12 hours of acute myocardial infarction. Forty-seven patients (44 males, 3 females; mean age 54.0 +/- 1.1 years) were randomly allocated to receive 1.5 million units of streptokinase either over 15 minutes (group 1, n = 24) or over one hour (group 2, n = 23) at a mean interval of 5.4 +/- 3.6 hours after onset of symptoms. All the patients received aspirin and intravenous heparin (1000 U/hr) for 96 hours after thrombolysis. Coronary angiography was performed in 43 patients (22 in group 1, 21 in group 2) prior to discharge from the hospital (mean 7 +/- 2.1 days after acute myocardial infarction) and patency of the infarct-related artery and grade of TIMI flow were determined. Infarct-related artery was patent (TIMI 2/3 flow) in 19 (86.4%) patients in group 1 as compared to 12 (57.1%) in group 2 (p < 0.05). TIMI grade 3 flow in the infarct-related artery was present in 13 (59.1%) in group 1 as compared to 7 (33.3%) in group 2 (p = 0.1). There was no significant difference between group 1 and 2 in time of presentation (mean 5.3 +/- 3.9 hrs vs 5.5 +/- 3.2 hrs), time to needle in hospital (25.6 +/- 11.2 min vs 26.3 +/- 6.2 min), site of infarct (anterior myocardial infarction 12 in group 1 vs 11 in group 2), relief of pain at 90 min (13 vs 12), more than 50 percent reduction of ST elevation at 90 minutes (17 vs 12) and left ventricular ejection fraction (48.8 +/- 9.1% vs 49.8 +/- 16.0%), respectively. Streptokinase was well tolerated in both the groups, although hypotension was more common with the accelerated regimen (5 in group 1 vs 3 in group 2; p = NS). Thus, 'accelerated' streptokinase given over 15 minutes in patients presenting within 12 hours of acute myocardial infarction is well tolerated and results in higher grades of TIMI flow in the infarct-related artery as compared to the "conventional" one-hour infusion regimen.

Adult↗
PubMedDate not supplied

Megadose heparin and streptokinase produce similar TIMI 3 flow at discharge in patients of acute myocardial infarction presenting between 7-12 hours.

The present study was undertaken to assess the impact of megadose heparin bolus on angiographic patency of infarct-related artery in patients of acute myocardial infarction presenting between 7-12 hours and to compare it with streptokinase. Forty-seven patients (27 males, mean age 58.1 +/- 9.6 years) of acute myocardial infarction between 7-12 hours of onset of chest pain were randomised to receive either megadose heparin bolus (300 IU/kg body weight, group 1, n = 24; or streptokinase 1.5 million units over one hour, group 2, n = 23). Parameters noted were: relief of pain at 90 minutes, 50 percent or more resolution of ST segment at 90 minutes, TIMI grade flow and left ventricular ejection fraction at discharge. Mean age (59.0 +/- 12.9 years in group 1; 57.2 +/- 8.1 years in group 2), mean time to drug (7.5 +/- 1.3 hours in group 1; 7.8 +/- 1.6 hours in group 2), site of anterior wall infarction (12 in group 1, 10 in group 2), relief of pain at 90 minutes (15 in group 1, 14 in group 2) and more than 50 percent resolution of ST segment elevation at 90 minutes (12 patients in each group) were similar. On coronary angiography performed in 42 patients (21 in each group) at a mean interval of 7.2 +/- 1.3 days after acute myocardial infarction, TIMI grade 3 flow was seen in 7 (33.3%) patients in each group and TIMI grade 2/3 flow was also similar in both the groups (p = NS). No major bleed occurred in either group. We conclude that heparin given as a megadose bolus produces similar TIMI 3 flow in infarct-related artery as compared to streptokinase in acute myocardial infarction patients presenting between 7-12 hours.

Aged↗
PubMedDate not supplied

Left ventricular pacing through coronary sinus tributaries: initial experience.

BACKGROUND: Left ventricular pacing is increasingly being used as a part of biventricular pacing in congestive heart failure but data on safety, feasibility, reliability and lead maturation are sparse. METHODS AND RESULTS: Seventeen patients (13 males and 4 females) with persistent symptomatic degenerative complete heart block underwent temporary left ventricular pacing by a left subclavian puncture through the coronary sinus to its tributaries using a unipolar permanent pacing lead connected to an external pulse generator. The left ventricular pacing was done for two weeks. Permanent right ventricular apical pacing was also done at the same time through a right cephalic vein cut-down or subclavian puncture and the pacing rate was kept below that of the initial left ventricular pacing rate. Pacing parameters of the left and right ventricles were assessed at the time of implantation and at two weeks. Out of 17 patients, left ventricular pacing was successful in 11 (67.7%) patients. The time taken for the total procedure was 56+/-18.1 min. Lead displacement was noted in one patient without loss of pacing. At the time of implant and after two weeks, left ventricular pacing threshold, impedance, R wave height and slew rate were not different as compared to right ventricular pacing. Holter recording for 24 hours revealed regular left ventricular pacing at the end of two weeks in all patients. CONCLUSIONS: The present study shows that left ventricular pacing through coronary sinus tributaries is feasible and reliable. Acute and subacute maturation of left ventricular pacing are similar to right ventricular apical pacing.

Aged↗
PubMedDate not supplied

Lipoprotein (a) and lipid levels in young patients with myocardial infarction and their first-degree relatives.

BACKGROUND: Studies among emigrant Indians have stressed the role of a powerful genetic factor, lipoprotein (a), in the causation of premature coronary artery disease. This study was carried out to assess lipoprotein (a) and lipid levels in 50 consecutive young north Indian patients (age less than 45 years, mean age 39+/-3.7 years) with myocardial infarction, their first-degree relatives (n=125, mean age 36+/-16 years), and age- and sex-matched controls (n=50, mean age 34+/-6.9 years). METHODS AND RESULTS: Blood samples for lipid estimation were taken within 24 hours of myocardial infarction and after overnight fasting for twelve hours. Lipoprotein (a) levels were estimated by the ELISA technique using preformed antibodies while lipid levels were estimated by kits using the colorimetric method. All were male patients. The mean lipoprotein (a) level was 22.28+5.4 mg/dl in patients, 13.88+5.19 mg/dl in their first-degree relatives and 9.28+22.59 mg/dl in controls. In addition, it was significantly higher in young patients with myocardial infarction and their relatives as compared to controls (p<0.001 for patients v. controls and p<0.05 for relatives v. controls). There was no significant difference in the levels of total cholesterol and low-density lipoprotein cholesterol among the three groups. High-density lipoprotein cholesterol was significantly lower in young patients with myocardial infarction (30.16+/-9.45 mg/dl) and their first-degree relatives (33.28+/-8.45 mg/dl) as compared to controls (46.8+/-8.04 mg/dl) (p<0.001 for patients v. controls and p<0.01 for relatives v. controls). Triglyceride levels were significantly higher in patients as compared to controls (202+/-76 mg/dl v. 149 + 82.99 mg/dl, p<0.05). Smoking was more prevalent in young patients with myocardial infarction as compared to controls (44% v. 36%, p<0.05). CONCLUSIONS: Smoking, high lipoprotein (a) and triglyceride levels and low high-density lipoprotein levels may be important risk factors for coronary artery disease in the younger population; also, there is familial clustering of high lipoprotein (a) levels in first-degree relatives of young patients with myocardial infarction.

Adult↗