PubMed Health⌕ Search

Biomedical subjects

P K Sidhu

Publications and source records attributed to P K Sidhu.

7 recordsLinked to original sources

Pharmacokinetic and pharmacodynamic interactions of tolfenamic acid and marbofloxacin in goats.

Pharmacokinetic and pharmacodynamic properties in goats of the non-steroidal anti-inflammatory drug tolfenamic acid (TA), administered both alone and in combination with the fluoroquinolone marbofloxacin (MB), were established in a tissue cage model of acute inflammation. Both drugs were injected intramuscularly at a dose rate of 2 mg kg(-1). After administration of TA alone and TA+MB pharmacokinetic parameters of TA (mean values) were Cmax=1.635 and 1.125 microg ml(-1), AUC=6.451 and 3.967 microgh ml(-1), t1/2K10=2.618 and 2.291 h, Vdarea/F=1.390 and 1.725Lkg(-1), and ClB/F=0.386 and 0.552 L kg(-1) h(-1), respectively. These differences were not statistically significant. Tolfenamic acid inhibited prostaglandin (PG)E2 synthesis in vivo in inflammatory exudate by 53-86% for up to 48 h after both TA treatments. Inhibition of synthesis of serum thromboxane (Tx)B2 ex vivo ranged from 16% to 66% up to 12h after both TA and TA+MB, with no significant differences between the two treatments. From the pharmacokinetic and eicosanoid inhibition data for TA, pharmacodynamic parameters after dosing with TA alone for serum TxB2 and exudate PGE2 expressing efficacy (Emax=69.4 and 89.7%), potency (IC50=0.717 and 0.073 microg ml(-1)), sensitivity (N=3.413 and 1.180) and equilibration time (t1/2Ke0=0.702 and 16.52 h), respectively, were determined by PK-PD modeling using an effect compartment model. In this model TA was a preferential inhibitor of COX-2 (COX-1:COX-2 IC50 ratio=12:1). Tolfenamic acid, both alone and co-administered with MB, did not affect leucocyte numbers in exudate, transudate or blood. Compared to placebo significant attenuation of skin temperature rise over inflamed tissue cages was obtained after administration of TA and TA+MB with no significant differences between the two treatments. Marbofloxacin alone did not significantly affect serum TxB2 and exudate PGE2 concentrations or rise in skin temperature over exudate tissue cages. These data provide a basis for the rational use of TA in combination with MB in goat medicine.

Animals↗

Influence of marbofloxacin on the pharmacokinetics and pharmacodynamics of tolfenamic acid in calves.

Pharmacokinetic and pharmacodynamic properties of tolfenamic acid (TA) in calves were determined in serum and fluids of inflamed (carrageenan administered) and non-inflamed subcutaneously implanted tissue cages after intramuscular administration both alone and in combination with marbofloxacin (MB). MB significantly altered the pharmacokinetics of TA: mean values were Cmax = 2.14 and 1.64 microg/mL, AUC = 27.38 and 16.80 microg.h/mL, Vd(area)/F = 0.87 and 1.17 L/kg, and ClB/F = 0.074 and 0.128 L/kg/h, respectively, after administration of TA alone and TA + MB. T(1/2)K10 and MRT were not significantly different for the two treatments. The pharmacodynamic properties of TA were not influenced by MB co-administration, in spite of the alterations in some TA pharmacokinetic parameters. TA inhibited prostaglandin E2 (PGE2) synthesis in vivo in inflammatory exudate by 50-88% for up to 48 h after both TA treatments. Inhibition of synthesis of serum thromboxane B2 (TxB2) ex vivo ranged from 40 to 85% up to 24 h after both TA and TA + MB. From the derived pharmacokinetic and eicosanoid inhibition data for TA, pharmacodynamic parameters for serum TxB2 and exudate PGE2 inhibition expressing efficacy (Emax = 78.1 and 97.5%), potency (IC50 = 0.256 and 0.265 microg/mL), sensitivity (N = 1.96 and 2.29) and the pharmacokinetic parameter equilibration time (t(1/2)K(e0) = 0.695 and 24.0 h), respectively, were determined. In this model TA was a nonselective inhibitor of cyclo-oxygenase (COX) (COX-1:COX-2 IC50 ratio = 1.37). TA, both alone and co-administered with MB, did not affect leucocyte numbers in exudate, transudate or blood. Partial attenuation of skin temperature rise over inflamed tissue cages and reduction of zymosan-induced skin swelling were recorded after administration of TA and TA + MB with no significant differences between the two treatments. These data provide a basis for the rational use of TA in combination with MB in calf medicine.

Animals↗

Efficacy of abamectin against ivermectin-resistant strain of Trichostrongylus colubriformis in sheep.

The efficacy of two formulations of abamectin, i.e. oral and injectable was determined against ivermectin-resistant strain of T. colubriformis in sheep. Twenty-four lambs were infected with 10,000 third stage larvae of ivermectin-resistant strain of T. colubriformis. Twenty-four days post-infection, the lambs were divided randomly into four groups of six animals each according to egg counts. The first group was left untreated and kept as a control. The second group was treated with ivermectin (oral) at 0.2mg kg(-1) body weight. The third group was treated with oral formulation of abamectin at 0.2mg kg(-1) body weight. The fourth group was treated with injectable formulation of abamectin at 0.2mg kg(-1) body weight. Fecal egg count and controlled slaughter tests were employed to determine the efficacy of abamectin (oral and injection) against ivermectin-resistant strain of T. colubriformis in sheep. Reduction in arithmetic mean fecal egg counts achieved by ivermectin (oral), abamectin (oral) and abamectin (injection) was 66, 98 and 76%, respectively 10 days after treatment. Ivermectin (oral), abamectin (oral) and abamectin (injection) reduced arithmetic mean worm burden by 63, 97 and 74%, respectively. The findings demonstrated that abamectin oral formulation was more effective than abamectin injection against ivermectin-resistant strain of T. colubriformis in sheep.

Administration, Oral↗

Serological analysis of patients treated with a new surgical hemostat containing bovine proteins and autologous plasma.

A randomized, controlled clinical study of the management of diffuse bleeding with CoStasis surgical hemostat, a new hemostat containing bovine thrombin and collagen with the patient's own plasma, included patients undergoing cardiac, hepatic, iliac, and general surgery. Sera from 92 patients treated with CoStasis and 84 control patients were collected preoperatively and at a post surgical follow-up of 8 weeks. Among the control group, 57 patients were treated with Instat collagen sponge in noncardiac indications. Results showed that antibody responses in the CoStasis clinical study were similar to the reported literature for all antigens screened and were not associated with any adverse reactions. The bovine thrombin preparations in CoStasis and other commercially available thrombins were compared with the use of SDS-PAGE and Western blot analyses. Within this clinical study, CoStasis was shown to be a safe and effective hemostatic product containing bovine thrombin and bovine collagen and no pooled human blood products.

Animals↗

Glucose-6-phosphate dehydrogenase deficiency in blood donors: screening by micromethaemoglobin reduction test.

500 blood donors were screened for G6PD deeiciency using micromethaemoglobin reduction (microMRT) test. Most of the blood donors were young adult males (95.8%). The overall incidence of G6PD deficiency was found to be 0.8%. There, was apparently decreased frequency of G6PD deficient blood donors with increasing age, and no relation could be ascertained between G6PD) deficiency and blood groups.

Adult↗