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Biomedical subjects

N C Jain

Publications and source records attributed to N C Jain.

155 records · Page 9Linked to original sources
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Identification of underivatized basic drugs in urine by capillary column gas chromatography.

A capillary column gas chromatographic (GC) method is described for detecting basic drugs of abuse and their metabolites in urine. One milliliter of urine, buffered with 400 microL Tris buffer (pH 9.5) containing 1.0 microgram/mL internal standard SKF 525A (proadifen hydrochloride), is extracted with 100 microL of 5% (v/v) isoamyl alcohol/hexane. The sample is vortexed for 30 sec and centrifuged for 10 min. The upper organic layer is directly injected into the GC, thus eliminating the need for an evaporation step. The GC is equipped with two DB-1701 fused silica capillary columns and nitrogen phosphorus detectors. The column oven is temperature programmed from 185 degrees to 265 degrees C at 8 degrees/min. Identification of the unknown drugs is accomplished by using retention time relative to that of a common internal standard.

Chromatography, Gas↗
PubMedDate not supplied

Simultaneous identification of cocaine and benzoylecgonine using solid phase extraction and gas chromatography/mass spectrometry.

A procedure for the simultaneous detection and quantitation of cocaine and benzoylecgonine from urine is described. Using solid phase extraction, cocaine, benzoylecgonine, deuterated cocaine, and deuterated benzoylecgonine (2 internal standards) are extracted from urine. Benzoylecgonine and the deuterated benzoylecgonine are derivatized to their trimethylsilyl esters. The underivatized cocaine and derivatized benzoylecgonine are detected by electron impact mass spectrometry in the selected ion monitoring mode. Both cocaine and benzoylecgonine are detected at concentrations of 50 ng/mL. In addition, the procedure is simple, rapid, and suitable for a large number of specimens.

Cocaine↗
PubMedDate not supplied

Simultaneous identification of amphetamine and methamphetamine using solid-phase extraction and gas chromatography/nitrogen phosphorous detection or gas chromatography/mass spectrometry.

A method for the simultaneous detection and quantitation of amphetamine and methamphetamine in urine is described. Using solid-phase extraction, amphetamine, methamphetamine, and n-propylamphetamine (internal standard) are extracted from urine samples. Drugs in their free form are identified using gas chromatography/nitrogen-phosphorous detection (GC/NPD), whereas their heptafluorobutyric anhydride derivatives are detected by gas chromatography/mass spectrometry (GC/MS) in the selected ion monitoring (SIM) mode. Limits of detection for both amphetamine and methamphetamine are approximately 35 ng/mL. The procedure is simple, rapid, and suitable for a large number of specimens (25 or more).

Amphetamine↗
PubMedDate not supplied

Evaluation of phencyclidine by EMIT d.a.u. utilizing the ETS analyzer and a 25-ng/mL cutoff.

This study evaluates the usefulness of the EMIT d.a.u. phencyclidine assay using the Syva ETS instrument to reliably detect phencyclidine in urine specimens at 25 ng/mL and above. More than 1600 urine specimens were screened over a one-month period. Fifty three (53) specimens screened positive (25 of these were previously tested positive by EMIT and GC/MS at or above the 25-ng/ml level and resubmitted as unknowns). Of the 53 specimens, 52 were confirmed positive by GC/MS. Reanalysis by EMIT of the one sample that was confirmed negative by GC/MS yielded a negative result. The absorbance difference between a negative sample and a sample containing 25 ng/mL of phencyclidine averaged 53 absorbance units with a standard deviation of 7.7 units. The absorbance difference between a negative sample and a sample containing 75 ng/mL of phencyclidine averaged 105 absorbance units with a standard deviation of 6.8 units.

Gas Chromatography-Mass Spectrometry↗
PubMedDate not supplied

Probable essential thrombocythemia in a dog.

Essential thrombocythemia (ET) in an 11-year-old dog was characterized by persistently high platelet counts (range, 4.19 X 10(6)/microliters to 4.95 X 10(6)/microliters, abnormal platelet morphology, marked megakaryocytic hyperplasia in the bone marrow, absence of circulating megakaryoblasts, and history of splenomegaly and gastrointestinal bleeding. Increased numbers of megakaryocytes and megakaryoblasts (15% to 20%) in the bone marrow were confirmed by a positive acetylcholinesterase reaction. Another significant finding was the presence of a basophilia in blood (4,836/microliters) and bone marrow. The marked persistent thrombocytosis, absence of reactive (secondary) thrombocytosis, abnormal platelet morphology, and quantitative and qualitative changes in the megakaryocytic series in the bone marrow suggested the presence of a myeloproliferative disease. Cytochemical and ultrastructural findings aided in the diagnosis of ET. The dog was treated with radiophosphorus. The results was a rapid decline in the numbers of megakaryoblasts and megakaryocytes in the bone marrow and platelets and basophils in the peripheral blood. The dog died unexpectedly of acute necrotizing pancreatitis and diabetes mellitus before a complete remission was achieved.

Animals↗
PubMedDate not supplied

Intravascular leukostasis and systemic aspergillosis in a horse with subleukemic acute myelomonocytic leukemia.

Leukemia is a neoplastic disease of one or more of the cell types of the hemopoietic system and is rarely diagnosed in the horse. This report describes a case of subleukemic acute myelomonocytic leukemia in an 11-year-old gelding. Preliminary cytological diagnosis was supported by two types of laboratory investigations. Cytochemical characterization of blood and bone marrow neoplastic cells was consistent with a myelomonocytic origin. Neoplastic blast cells in peripheral blood were labeled by monoclonal antibodies specific for cell surface molecules of horse granulocytes, but they were not labeled by antibodies to T- or B-lymphocytes or macrophages. Treatment was attempted but was unsuccessful. At necropsy, intravascular leukostasis was present in all tissues examined. Fungal hyphae were also found in lung interstitium and colonic submucosa, suggesting the presence of a systemic mycosis. Nucleated cells were isolated from peripheral blood and cultured in vitro; they survived for up to 2 weeks and had evidence of cell division that was not sustained. Frozen-thawed cells stored in liquid nitrogen were also successfully cultured in vitro, but no permanent cell lines could be established.

Animals↗
PubMedDate not supplied

Patterns of drug use among methadone maintenance patients in Los Angeles county.

Any evaluation of the effectiveness of methadone maintenance programmes in rehabilitating heroin addicts is inherently complex and subject to varied interpretations, both scientific and philosophical. From a scientific perspective, it is necessary to accumulate sufficient factual data to validate any hypothetical conclusions. A retrospective survey of drug-use patterns among the methadone maintenance population of Los Angeles County was undertaken in an effort to provide some such information. Over 5,000 urine samples from 730 paitients were analysed for eleven drugs over a two-month period in 1975. Over 23 per cent of these samples were found positive for a drug other than methadone and 80 per cent of these positives were attributed to illicitly used drugs. The opiates (codeine and morphine) comprised almost 74 per cent of the drugs found while barbiturates and amphetamine and/or methamphetamine contributed 16 per cent and 10 per cent to the total, respectively.

Adult↗
PubMedDate not supplied

Early hematologic changes in rhesus macaques (Macaca mulatta) infected with pathogenic and nonpathogenic isolates of SIVmac.

Early hematologic changes were studied over a 14 day period in three groups of six rhesus macaques intravenously infected with pathogenic and nonpathogenic isolates of SIVmac. Abnormalities in blood included a mild blood loss anemia, sporadic lymphopenia, and variable CD4+ and CD8+ T lymphocyte numbers. Prominent bone marrow findings in macaques inoculated with pathogenic uncloned SIVmac and molecularly cloned pathogenic SIVmac-239 were hypercellularity, myeloid and megakaryocytic hyperplasia, and lymphoid aggregates. Infrequent mild morphologic abnormalities were present in macaques infected with a nonpathogenic molecular clone, SIVmac-1A11.

Anemia↗