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P B Parab

Publications and source records attributed to P B Parab.

30 records · Page 2Linked to original sources

Brugia malayi: serum dependent cell-mediated reactions to microfilariae.

Sheathed and exsheathed microfilariae of Brugia malayi are killed by normal rat cells in the presence of immune serum in vitro. Immune serum heated at 56 degrees C for 1 hour lost this activity which was largely restored by the addition of fresh normal rat serum. EDTA but not EGTA abolished this activity indicating the operation of complement by alternate pathway. Fresh normal rat serum alone promoted cellular adherence without exerting cytotoxicity to the microfilariae. The activity in the immune serum could be removed with Staphylococcus aureus cells containing Protein A or anti-IgG antiserum. The activity could also be absorbed to and eluted from Protein A--sepharose CL-4B suggesting the involvement of IgG. Neutrophils and macrophages participate in the antibody dependent cell-mediated cytotoxicity phenomenon. Eosinophils while adhering to the microfilariae exert cytotoxicity only to the exsheathed parasites.

Animals↗

The effect of p-aminobenzoic acid and folic acid on the development of infective larvae of Brugia malayi in Aedes aegypti.

Adult Aedes aegypti mosquitoes, infected with the subperiodic Brugia malayi, were found to enhance the development of the filarial parasites to the infective stage when they were exposed to a cotton pad soaked in 10% sucrose solution containing p-aminobenzoic acid (PABA) in 0.001, 0.005, 0.01, 0.05 and 0.1% concentrations. Similarly, larval development increased when the mosquitoes were fed with folic acid at 0.001, 0.01 and 0.1% concentrations. This stimulation was more when PABA or folic acid was given prior to the infected blood meal through the developmental period of the larvae. The data thus suggest that PABA and folic acid are nutrients for the development of B. malayi-microfilariae to the infective stage in A. aegypti.

4-Aminobenzoic Acid↗

Hepatobiliary kinetics of 113mIn-phenolphthalexon.

Phenolphthalexon, a compound with iminodiacetic acid as a functional group, has been labelled with 113mIn to high chemical purity and its usefulness in studies of biliary excretion patency has been studied. Organ distribution of 113mInphenolphthalexon in mice was characterized by high liver uptake (50.8% of the administered dose after 5 min) and rapid clearance through the gall bladder. An animal model for studying obstruction of biliary excretion has been developed. Data on the kinetics of the radiopharmaceutical were obtained by collecting in-vivo data through an on-line computer.

Animals↗

Labeling of red blood cells with Tc-99m after oral administration of SnCl2: concise communication.

In vivo labeling of red blood cells with Tc-99m was possible after prior oral administration of SnCl2, both in rats and human volunteers. Absorption of oral SnCl2 was low but sufficient for more than 95% labeling efficiency. Prior i.v. administration of stannous chloride is known to induce in vivo labeling of red blood cells with pertechnetate. We have observed that such labeling is possible even after oral administration of stannous chloride. Nearly 95% of the circulating radioactivity and 93.7% of the administered radioactivity was in RBCs 30 min after i.v. injection of 99mTcO4- in rats that were fed 5 mg of stannous chloride (3.13 mg Sn2+ ion) 2 hr before injection. Red blood cells from four human volunteers could bind pertechnetate, both in vitro and in vivo, after oral administration of 100 mg of SnCl2. We have obtained a blood-pool image of the human heart by labeling the RBCs in vivo by this method. We have also studied various parameters affecting the in vivo binding of RBCs with Tc-99m--such as the amount of orally administered SnCl2, the time of injection of radionuclide after oral SnCl2, and the optimum time for the imaging.

Administration, Oral↗

Analysis of B. malayi microfilarial antigens by immunoblotting.

BALB/C mice were immunized with heavy or low infection of live B. malayi microfilariae or immunised with different fractions of the microfilarial antigens. Antibody levels and antibody dependent macrophage mediated cytotoxicity to B. malayi microfilariae were determined in the immunized sera. Antigens responsible for induction of antibodies were recognised in B. malayi microfilarial extract by immunoblotting. Appearance of cytotoxic antibodies correlates with recognition of certain common antigens in microfilarial extract such as 45, 54, 62, 66 and 76 KDa mol. wt. proteins.

Animals↗