Search PubMed⌕ Search

Biomedical subjects

K Kaur

Publications and source records attributed to K Kaur.

86 records · Page 5Linked to original sources
PubMed1983

Genetic studies on the role of the nucleoside transport function in nucleoside efflux, the inosine cycle, and purine biosynthesis.

A mutant clone (AU-100) which is 90% deficient in adenylosuccinate synthetase activity was characterized from wild-type murine S49 T-lymphoma cells. This AU-100 cell line and its hypoxanthine-guanine phosphoribosyltransferase-deficient derivative, AUTG-50B, overproduce purines severalfold and excrete massive amounts of inosine into the culture medium (Ullman et al., Proc. Natl. Acad. Sci. U.S.A. 79:5127-5131, 1982). We introduced a mutation into both of these cell lines which make them incapable of taking up nucleosides from the culture medium. The genetic deficiency in nucleoside transport prevents the adenylosuccinate synthetase-deficient AU-100 cells from excreting inosine. Because of an extremely efficient intracellular inosine salvage system, the nucleoside transport-deficient AU-100 cells also no longer overproduce purines. AUTG-50B cells which have been made genetically deficient in nucleoside transport still overproduce purines but excrete hypoxanthine rather than inosine. These studies demonstrate genetically that nucleoside transport and nucleoside efflux share a common component and that nucleoside transport has an important regulatory function which profoundly affects the rates of purine biosynthesis and purine salvage.

Adenylosuccinate Synthase↗
PubMed1981

Perforation of a suppurative solitary renal cyst.

A fatal case of rupture of a large infected renal cyst is presented. Antibiotic therapy is indicated after aspiration of a suppurative renal cyst, and recurrence, particularly if large, is an indication for prompt surgical intervention.

Female↗
PubMed1981

Selective area tuberculosis surveys in Singapore 1978.

A random population sample survey in Singapore 1975 revealed that a relatively high proportion of active pulmonary tuberculosis patients remained undiagnosed, mainly in the older age groups. Previous studies disclosed the cause to the lack of symptoms of concern in these patients. A new programme was devised to discover hidden elderly patients by mass chest X-ray screening of population aged 45 years and older living in areas with known high incidence of tuberculosis. The yield of cases was less than expected mainly due to the dislocation and dispersion of population from recent extensive urban re-development in Singapore. Nevertheless the results were comparable to the most productive case finding programme carried out in this department.

Aged↗
PubMedDate not supplied

Immunochemical evidence supporting 2-pentylpyrrole formation on proteins exposed to 4-hydroxy-2-nonenal.

Previous model studies suggested the formation of lysine-based 2-pentylpyrroles as novel late adduction products formed upon exposure of proteins to the lipid peroxidation product 4-hydroxy-2-nonenal (HNE). Two 2-pentylpyrrole immunogens were prepared, one by treating keyhole limpet hemocyanin (KLH) directly with 4-oxononanal and the other by preformation of 6-(2-pentylpyrrol-1-yl)hexanoic acid from 6-aminocaproic acid and 4-oxononanal, followed by carbodiimide coupling to KLH. Pyrrole content and lysine modification in KLH were assayed independently. Following immunization of rabbits, antibody titer increased and plateaued over a 4 month period. The structural specificity of the IgG fractions of the antisera was evaluated through comprehensive competitive ELISA studies. These antibodies were used to verify the time-dependent appearance of the 2-pentylpyrrole epitope in protein exposed to HNE. Potential advantages of antibodies recognizing "advanced lipid peroxidation end products" over those recognizing "early" HNE adduction products are discussed.

Aldehydes↗
PubMedDate not supplied

Diagnosing ascitic etiology on a biochemical basis.

BACKGROUND/AIMS: The analysis of ascitic fluid has been complicated by several new tests. To simplify its assessment, we evaluated ascitic fluid pH with six other parameters prospectively and simultaneously in blood and ascitic fluid in sixty patients with ascites. METHODOLOGY: Sixty patients were selected on whom abdominal paracentesis was performed in order to determine which tests were the most reliable for the etiological diagnosis of ascites. Their ascitic fluid pH, cholesterol, albumin, and total proteins were analyzed to distinguish between malignant and cirrhotic ascites. The diagnosis of cirrhosis was based on histological findings, and/or clinical, biochemical, and endoscopic/ultrasonographic findings in whom percutaneous liver biopsy was contraindicated. RESULTS: The serum-ascites albumin gradient was higher (p<0.001) in cirrhotic as compared to tubercular, malignant or cardiac ascites. We discovered that ascitic fluid lactate dehydrogenase and cholesterol were best for diagnosing malignant ascites, ascitic fluid glucose and ascitic fluid/blood glucose ratio were perfect for diagnosing tubercular ascites, and ascitic fluid pH and lactate dehydrogenase were suitable for diagnosing spontaneous bacterial peritonitis. Correspondingly, ascitic fluid albumin, ascitic fluid/serum albumin, total proteins, and serum ascites albumin gradient were best for diagnosing sterile cirrhotic ascites. CONCLUSIONS: Diagnostic paracentesis is a useful procedure. The practice of ordering a battery of tests on every ascitic fluid specimen should be abandoned. Rather, an algorithm approach should be adopted in which the results of initial analysis guide us to further relent tests that help in arriving at the etiology of ascites.

Albumins↗