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Biomedical subjects

N C Jain

Publications and source records attributed to N C Jain.

At least 91 records · Page 5Linked to original sources
PubMed1977

Simultaneous determination of cocaine and benzoyl ecgonine in urine by gas chromatography with on-column alkylation.

A gas chromatographic procedure has been developed for the simultaneous determination of cocaine and benzoyl ecgonine in urine specimens. The two drugs are extracted by isopropanol/chloroform from urine samples saturated with a bisalt buffer. The organic extract is evaporated to dryness, and an aliquot of the residue is injected onto the gas chromatograph to determine the presence of cocaine and the location of any extraneous peaks. Benzoyl ecgonine is then analyzed as its particular alkyl ester subject to the least interference from extraneous peaks as observed in an initial underivatized injection. The reconstituted residue is co-injected with the appropriate dimethylformamide dialkyl acetal for on-column alkylation. The use of two columns or more than one benzoyl ecgonine alkyl ester gives positive identification, and the use of isopropyl benzoyl ecgonine as an internal standard allows accurate quantification.

Alkylation↗
PubMed1977

Experimental immunologic thrombocytopenia in dogs: a study of thrombocytopenia and megakaryocytopoiesis.

Immunologic thrombocytopenia was induced in dogs by intravenous or intraperitoneal injection of rabbit anti-canine platelet serum (APS) or by intraperitoneal injection of the IgG fraction of the APS. In contrast, dogs injected with normal rabbit serum (NRS) or the IgM fraction of the APS did not develop thrombocytopenia. Marrow samples obtained at 24-96 h after inoculation of the IgG fraction contained megakaryocytes giving a positive reaction with flurescein isothiocyanate or horseradish peroxidase-conjugated anti-rabbit globulin. In contrast, negative results were obtained with megakaryocytes in marrow samples collected before injection of the IgG fraction or after injection of the IgM fraction or NRS. The attachment of anti-platelet antibody to the surface of megakaryocytes was associated with appearance of morphologic abnormalities, particularly in mature megakaryocytes. Simultaneously, the number of immature megakaryocytes and acetylcholine esterase (AChE)-positive small cells (presumably megakaryocyte precursors) increased considerably. These changes coincided with the development of thrombocytopenia, and subsided as recovery ensued.

Acetylcholinesterase↗
PubMed1977

Fusiform erythrocytes resembling sickle cells in angora goats: light and electron microscopic observations.

Fresh blood from nine mature non-pregnant angora goats was found to contain a varying proportion of spindle-shaped, fusiform, triangular, pear-shaped, and other bizarre forms of erythrocytes in addition to normal discoid biconcave erythrocytes. The number of spindled and fusiform erythrocytes varied from 2 to 66 per cent, with two goats having such cells in excess of 50 per cent. Other aberrant forms of erythrocytes ranged from 3 to 54 per cent. Although the aberrant erythrocytes seemed to be present intravascularly, all goats studied were clinically normal and exhibited no other haematological abnormality. Light and electron microscopic observations indicated that polymerisation of haemoglobin in the form of longitudinal tubular fibres was responsible for conferring the fusiform and spindle shapes to erythrocytes, a phenomenon akin to that seen in sickle-shaped human and deer erythrocytes.

Anemia, Sickle Cell↗
PubMed1976

Rapid screening and confirmation of amphetamine, methamphetamine, methadone, and methadone metabolite in urine by gas/thin layer chromatography.

A method suitable for large scale screening and confirmation of urine speciments for amphetamine, methamphetamine, methadone, and its primary metabolite (2-ethylidene-1,5-dimethyl-3,3-diphenlypyrrolidine) is described. The drugs are extracted from alkaline urine into an organic solvent. The amphetamine drugs are then back-extracted into a small volume of acid and identified by gas chromatography both as free bases on a 10% Apiezon L-10% KOH column and as their trifluoracetamide derivatives on a 3% OV-17 column. The organic layer, which still contains methadone and its primary metabolite, is analyzed by split-sample thin-layer chromatography using two solvent systems: ethyl acetate: methylene cloride: concentrated ammonium hydroxide (90:10:0.7) and methanol: chloroform: concentrated ammonium hydroxide (74:25:0.8). These solvent systems separate methadone from its primary metabolite without interference from other drugs or urinary substances.

Amphetamine↗
PubMed1976

Mass screening and confirmation of barbiturates in urine by RIA/gas chromatography.

A rapid, sensitive and specific procedure is described for the mass screening and confirmation of barbiturates in urine specimens. The method is sensitive to 0.5 mug/ml levels of the commonly used barbiturates. The urine samples are screened by radioimmuno-assay. Specimens screened positive are confirmed by gas-liquid chromatography using a flame ionization detector. The barbiturates are analyzed as free acids on a 10% UC W-98 column and as their dimethyl derivatives on a 3% OV-17 column. This dual approach eliminates false positives caused by interfering substances which may be present in the urine, thus resulting in a method specific for the barbiturates.

Barbiturates↗
PubMed1976

Detection of antiplatelet antibody in serum and on megakaryocytes of dogs with autoimmune thrombocytopenia.

Blood and bone marrow samples from 13 thrombocytopenic dogs were examined to determine whether immunologic thrombocytopenia existed. Antiplatelet antibody was detected in serum of 8 of the dogs by platelet factor 3 test or its modification. Moderate to strong immunofluorescence of megakaryocytes was noticed in bone marrow smears stained with rabbit anticanine globulin conjugated with fluorescin isothiocyanate. Negative results were obtained with serum and bone marrow samples collected from 6 of the dogs during therapy for autoimmune thrombocytopenia. Clinical and laboratory findings varied in individual patients with circulating antiplatelet antibodies. Thrombocytopenia was present in all the dogs, with platelet counts ranging from less than 3,000 to 20,000/mu1 of blood. Signs of bleeding in tissues and body cavities were present in all dogs, but anemia was evidenced in only 3 dogs. Differential leukocyte counts were variable. Morphologic abnormalities such as vacuolation and reduced or absence of granulation of the cytoplasm and nuclear fragmentation were seen in some megakaryocytes.

Animals↗
PubMed1976

Conversion of chronic staphylococcal mastitis to acute gangrenous mastitis after neutropenia in blood and bone marrow produced by an equine anti-bovine leukocyte serum.

A stock strain of Staphylococcus aureus of mastitis origin, characterized by alpha-, beta-, and delta-toxins, was used to produce chronic mastitis of 20 to 300 days' duration in 6 lactating mammary quarters of 4 cows. Early acute Streptococcus agalactiae mastitis was produced in 1 additional mammary quarter of 1 cow. Equine anti-bovine leukocyte serum (EABLS) was administered to all cows by continuous intravascular drip for 12 to 32 hours. Neutropenia in blood and partial depletion of neutrophil reserve in bone marrow were produced. Chronic subclinical staphylococcal mastitis in 2 quarters of 1 cow changed to gangrenous mastitis by the 40th hour after EABLS administration and led to death of the cow. The disappearance of neutrophil leukocytes from the milk was followed by uninhibited multiplication of S aureus. Probably, staphylococcal leukocidins accelerated the destruction of neutrophils in the milk as S aureus multiplication became intensified. In another quarter of the same cow that was infected with Str agalactiae, neutrophil leukocytes were present in milk as long as 3 days after their disappearance from blood and bone marrow. This may give some indication of the extravascular life-span of the neutrophil in the udder in mastitis. The 2nd cow died at the 16th hour from the start of EABLS administration and at a time when gangrenous mastitis was in the initial stages of development. The S aureus-infected quarters of the 2 remaining cows did not become gangrenous. Administration of EABLS to these 2 cows did not significantly reduce the numbers of neutrophil leukocytes entering the milk of the 3 S aureus-infected quarters. It is concluded that continuous diapedesis of neutrophil leukocytes into the milk in chronic staphylococcal mastitis protects the gland against the development of gangrenous mastitis in the presence of a strain of S aureus capable of alpha-toxin production.

Agranulocytosis↗
PubMed1975

Thin-layer chromatographic screening and confirmation of basic drugs of abuse in urine.

Thin-layer chromatographic procedures are presented for the positive identification of methodone, primary metabolite of methodone (2-ethylidine-1,5-dimethyl-3,3-diphenylpyrrolidine), propoxyphene, norpropoxyphene, cocaine, benzoylecgonine, methoqualone, and phencyclidine from urine specimens. Initial screening of specimens is done by developing plates in ethyl acetate-methanol-diethylamine (90:10:1.6). Samples screened positive are confirmed in methylene chloride-methyl ethyl ketone-concentrated ammonium hydroxide (74:25:0.8), depending on the drug(s) indicated by the screening procedure. The method is quite sensitive, detecting most of the listed drugs at levels of 1.0 mug/ml or less.

Chromatography, Thin Layer↗
PubMed1975

A scanning electron microscopic study of platelets of certain animal species.

Comparative morphology of platelets of the dog, cat, cow, horse, sheep, and goat was studied with the scanning electron microscope and was found generally similar. Most of the platelets were slightly biconvex of flat with relatively smooth surface and even contour. Some of these platelets had few short marginal filaments, oriny protuberances on the surface. A small number of platelets exhibited surface irregularity and few long pseudopods which were thought to result from platelet activation during the processing of blood. The number os such irregular platelets increased in stored blood and in blood fixed at 4 degrees C.

Animals↗
PubMed1975

Rapid mass screening and confirmation of urinary amphetamine and methamphetamine by gas chromatography.

A rapid and simple procedure is described for the mass screening and confirmation of amphetamine and methamphetamine in urine using gas chromatography with flame ionization detector. The amphetamine drugs are screened as free drugs on a 10% Apiezon L-10% KOH column and confirmed as their trifluoroacetamide derivatives on a 3% OV-17 column. This dual approach eliminates false positives and interfering substances that may be present in the urine and is, therefore, specific for amphetamine and methamphetamine.

Amphetamine↗
PubMed1975

Gas chromatographic/thin-layer chromatographic analysis of acetylated codeine and morphine in urine.

This procedure positively identifies codeine and morphine in urine. Urine samples are hydrolyzed and extracted with organic solvent, and the extracts are evaporated and acetylated. The presence of codeine and morphine is ascertained by gas chromatography (3% OV-25 and 3% Poly-A 103 columns) and confirmed by thin-layer chromatography (system: ethyl acetate/acetone/concd ammonium hydroxide, 100/10/4.5 by vol; reagent: iodoplatinate). As little as 0.5 mg each of codeine and morphine per liter, in free and conjugated forms, is detectable by this method.

Acetylation↗