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Y Singh

Publications and source records attributed to Y Singh.

117 records · Page 7Linked to original sources

Characterization of ciprofibrate and clofibric acid as peroxisomal proliferators in primary cultures of rat hepatocytes.

We have determined the comparative activities of peroxisomal proliferators, ciprofibrate and clofibric acid on various hepatic parameters associated with endoplasmic reticulum, mitochondria and peroxisomes in primary cultures of rat hepatocytes. We have measured the activities of carnitine acetyltransferase and fatty acylCoA oxidase, and the amount of 60 and 80 kD polypeptides as biochemical markers of the peroxisomal function; laurate hydroxylase and cytochrome P-450 as markers of the endoplasmic reticulum; and carnitine palmitoyltransferase as a marker of mitochondria in primary cultures of hepatocytes. Ciprofibrate (0.01 to 0.3 mM) and clofibric acid (0.1 to 3 mM) produced similar changes in several components of cultured hepatocytes within 72 hr. Increases of protein (18 and 11%), carnitine palmitoyltransferase (23 and 97%), cytochrome P-450 (37 and 49%), carnitine acetyltransferase (484 and 614%), fatty acylCoA oxidase (529 and 931%) and laurate hydroxylase (624 and 671%) were obtained in hepatocytes after a 72-hr exposure to 0.1 mM ciprofibrate and 1.0 mM clofibric acid, respectively. In cultured hepatocytes, ciprofibrate was about 30-fold more active than clofibric acid for the stimulation of carnitine acetyltransferase, laurate hydroxylase and fatty acylCoA oxidase activities. Ciprofibrate was also more potent than clofibric acid as an inducer of the 60 and 80 kD proteins in hepatocytes. The maximal drug-induced increases in carnitine acetyltransferase activity were not additive, and the induction of carnitine acetyltransferase by ciprofibrate was blocked by addition (1 micrograms per ml) of cycloheximide or actinomycin D. Changes in protein and RNA synthesis preceded the drug-induced increases of carnitine acetyltransferase activity.(ABSTRACT TRUNCATED AT 250 WORDS)

Acetyltransferases↗

Venous thrombosis associated with the placement of peripherally inserted central catheters.

PURPOSE: Peripherally inserted central catheters (PICCs) have become an essential component of the management of an increasing number of patients, including patients who may require hemodialysis. Reported symptomatic venous thrombosis rates associated with PICC lines are based on clinical signs and symptoms and range from 1% to 4%. The purpose of this study is to evaluate the true rate of thrombosis of upper extremity veins after the placement of PICCs and the potential impact on future access in hemodialysis patients. MATERIALS AND METHODS: A retrospective analysis was performed. Patients who had (i) normal findings during initial venography, (ii) PICC placement, and (iii) who underwent subsequent repeated venography were included. Age, sex, vein cannulated, catheter size, location, and incidence of thrombosis were analyzed. RESULTS: Three hundred fifty-four PICCs were placed in 119 patients. Of the 144 extremities, 137 had normal findings during initial venography. Of the 137 extremities, 32 developed thrombosis of the cannulated vein (or central veins) after initial PICC placement (23.3%). When all extremities with multiple PICC lines placed were considered, 52 developed thrombosis, for an overall thrombosis rate of 38%. The incidence of thrombosis by site was cephalic 57%, basilic 14%, and brachial 10%. No significant differences were noted in the rates of thrombosis by age, sex, or catheter size. CONCLUSIONS: There is a relatively high rate of venous thrombosis associated with PICCs, particularly cephalic thrombus. Because of the high rate of thrombosis associated with these catheters, an alternative mode of access should be considered in current or potential hemodialysis patients. All patients with a history of PICC line placement requiring dialysis access should undergo upper extremity venography prior to the placement of permanent access.

Adolescent↗

Optimal prefixation of cells to demonstrate apoptosis by the TUNEL method.

OBJECTIVE: To determine the optimal fixation method for cultured human ovarian cancer cell line SHIN-3 to document cisplatin-induced apoptosis by the terminal deoxynucleotidyl transferase-mediated biotinylated dUTP nick end-labeling (TUNEL) assay. STUDY DESIGN: Cisplatin-treated cancer cell suspensions were (1) fixed in 4% buffered formalin for 10 minutes (BF group); (2) treated with 2% Carbowax in 50% ethanol (CW) for 10 minutes and then fixed in 100% ethanol for one hour (CW + ET); or (3) treated with CW for 10 minutes and then fixed in 4% buffered formalin for one hour (CW + BF). Cell morphology, adhesion to the glass slides and TUNEL reactivity were compared among the three groups. The effects of prolonged prefixation of cell suspensions in CW and of the postfixation of cell smears in BF for one, three and seven days were also examined. RESULTS: CW + BF treatment yielded satisfactory cell morphology, minimum cell loss and an excellent TUNEL reaction. However, prolonged prefixation in CW resulted in cell shrinkage. CONCLUSION: CW + BF treatment can be widely recommended for use with cytologic preparations for the TUNEL assay.

Antineoplastic Agents↗

Intra-abdominal needles: an enigma (a report of two cases).

Ingested sharp metallic bodies perforate the gut surprisingly rarely. Perforation and migration of such a foreign body may be silent. Patients may present with unrelated symptoms and the discovery of foreign body on radiological examination of the abdomen may come as a surprise. History of ingestion is usually difficult to obtain. Foreign bodies after perforation have been reported to migrate to almost any intraabdominal or rarely to even extra-abdominal sites. Migration to the liver, mesentery or the anterior abdominal wall, however, is extremely rare. We report two cases of young women with two ingested needles in each which perforated silently and in one case migrated to the liver and the anterior abdominal wall while in the other they migrated to the mesentery of the small intestine and the anterior abdominal wall.

Abdominal Pain↗

Experiences of identification and differentiation as functions of leprosy, personality and age.

It is a study of sociogenic need satisfactions that determines the homeostasis of 'being' by remaining contingent conditions of perpetuation or debasement of the social 'self'. The paper has a focus on identification satisfaction and differentiation experience of patients of the highly stigmatized leprosy. The study proceeds with an 'Experimental Group--Control-Group' randomized design. Experimental Groups are two, viz., those of Lepromatous and Non-lepromatous patients. 'Control Group' consists of 'disease-free' normal people. The three independent variables are disease types, age, personality factors. The dependent variables are two, viz., score of identification satisfaction and differentiation experience, measured by standardized tools. Each dependent variable has four '3 X 3 X 2' factorial experiments to test 56 'Null Hypotheses'. The sample consists of 360 elements for each one of the eight experiments. Leprosy elements are drawn from the Central JALMA Institute for Leprosy and the 'Kushta Seva Sadan' (Agra). The 'F' test is run for statistical verification of 'Null hypotheses'. Results show presence of 'role-reversion' and 'role negation' of age and personality factors. The disease possesses 'anti-roles'. It does not allow age and personality factors to promote identification satisfaction and to demote differentiation and experience. The disease actively promotes differentiation and demotes identification through its own 'alien system'. The senescents are the greatest sufferers. 'Social Stigma' works a 'social thanatos' and exposes senescents to substantial 'self-erosion'.

Adolescent↗

Lupus anticoagulant and anticardiolipin antibodies in systemic lupus erythematosus.

BACKGROUND: Lupus anticoagulant and anticardiolipin antibodies are antiphospholipid antibodies which have been independently associated with a high incidence of thrombotic diseases. However, the importance of their combined occurrence has not yet been examined. METHODS: We investigated 70 patients with systemic lupus erythematosus for the presence of anticardiolipin antibodies paying particular attention to a history of thrombosis and abortion. Lupus anticoagulant was detected using the kaolin clotting time, its mixing tests with normal plasma and the inosithin neutralization test. Anticardiolipin antibodies were detected using the ELISA technique. RESULTS: Lupus anticoagulant was detected in 11 patients (16%) and anticardiolipin antibodies in 13 (19%). Six patients were positive for both lupus anticoagulant and anticardiolipin antibodies. These patients had a higher incidence of thrombosis or recurrent abortion (5 of 6) compared to those with lupus anticoagulant (2 of 5) or anticardiolipin antibodies alone (1 of 7). The amount of inosithin required to neutralize lupus anticoagulant was greater [mean (SD) 27.5 (20.5) micrograms] in patients with both lupus anticoagulant and anticardiolipin antibodies than in patients with lupus anticoagulant alone [mean (SD) 4.0 (5.4) micrograms]. CONCLUSION: The presence of lupus anticoagulant is associated with thrombosis and recurrent abortion which are more frequent when both lupus anticoagulant and anticardiolipin antibodies are present and these patients probably have more severe disease as the amount of inosithin required to neutralize the lupus anticoagulant was greater.

Adolescent↗

Cytotoxicity of anthrax lethal factor microinjected into macrophage cells through Sendai virus envelopes.

Lethal toxin (LT) secreted by Bacillus anthracis consists of two proteins, protective antigen (PA) and lethal factor (LF). LT causes lysis of macrophages and derived cell lines at low concentrations. PA binds to the cell surface receptors and mediates translocation of LF into cytosol of mammalian cells. Internalization of LF into cytosol by osmotic lysis of pinocytic vesicles requires high concentration of LF for cell lysis. To examine the possible cell lysis by LF at low concentration, we introduced LF directly into cytosol of J774A.1 cells through reconstituted Sendai virus envelopes. The introduction of LF lysed J774A.1 cells in a concentration dependent manner. Internalization of PA alone through virosome had no toxic effect on J774A.1 cells. In the process of cytotoxicity LF was not cleaved by cellular proteases. Unlike many protein toxins, golgi was not involved in the expression of lethal toxin activity. These results indicate that LF is the toxic component of anthrax lethal toxin and prior proteolytic processing or trafficking through golgi is not required for its activity.

Animals↗

Factors related to axillary lymph node metastasis in T1 breast carcinoma.

The current study was performed on 38 cases of T1 breast cancers ( 2 cm in greatest diameter) to identify the factors related to recognition of axillary lymph node (AxLN) metastasis. Ten patients (26.3%) had lymph node metastases. Comparing the AxLN positive (+) group with the AxLN negative (-) group revealed that tumor size and hormone receptor status as well as age of the patients were not significantly different. However, the Ki-67 labeling index (22.2 +/- 5. 9% vs. 12.5 +/- 2.8%), the microvessel count (43.8 +/- 12.4/0.785 mm2 vs. 27.0 +/- 8.4/0.785 mm2) and bcl-2+ cases (70% vs. 29%) were significantly higher in the AxLN+ cases. These results suggest that the Ki-67 labeling index, microvessel count and Bcl-2 expression, especially when combined, are useful predictors of AxLN metastases in T1 breast cancers.

Adult↗