1976
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Richardson J, McGurgan P, Cheema S, Prasad R, Gupta S. Spinal endoscopy in chronic low back pain with radiculopathy. A prospective case series. Anaesthesia 2001; 56:454-60. [PMID: 11350333 DOI: 10.1046/j.1365-2044.2001.01524-3.x] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
All 38 patients listed for day-case spinal endoscopy over a 12-month period (April 1998 - April 1999), who had chronic severe low back pain with a radiculopathic element, were studied prospectively. The mean [range] pain duration before treatment was 10.9 [2-26] years and 50% had failed back surgery syndrome. In all patients in whom treatment was completed (n = 34), the pain-generating nerve roots were located through symptom interaction with the patient. All had epidural scar tissue, 14 (41%) having dense adhesions. Mobilisation of adhesions around the nerve root (neuroplasty) was performed so that a pocket was formed for the subsequent placement of bupivacaine, Depomedrone and clonidine. No intra-operative complications occurred and side-effects were minimal. Follow-up over a 12-month period showed statistically significant reductions in pain scores and disability. Spinal endoscopy may be the diagnostic method of choice for epidural fibrosis. It has substantial therapeutic and research potential. Prospective randomised studies are required.
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1977
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Gupta S, Piraka C, Jaffe M. Lamivudine in the treatment of polyarteritis nodosa associated with acute hepatitis B. N Engl J Med 2001; 344:1645-6. [PMID: 11374371 DOI: 10.1056/nejm200105243442118] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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1978
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Gupta S, Anthony A, Pernis AB. Stage-specific modulation of IFN-regulatory factor 4 function by Krüppel-type zinc finger proteins. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2001; 166:6104-11. [PMID: 11342629 DOI: 10.4049/jimmunol.166.10.6104] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Optimal humoral responses depend on the activation of Ag-specific B cells, followed by their progression toward a fully differentiated phenotype. Acquisition of stage-appropriate patterns of gene expression is crucial to this differentiation program. However, the molecular mechanisms used by B cells to modulate gene expression as they complete their maturation program are poorly understood. IFN-regulatory factor 4 (IRF-4) plays a critical role in mature B cell function. Using the transcriptional regulation of the human B cell activation marker CD23 as a model system, we have previously demonstrated that IRF-4 is induced in response to B cell-activating stimuli and that it acts as a transactivator of CD23 gene expression. We have furthermore found that IRF-4 function can be blocked by B cell lymphomas 6 (BCL-6) protein, a Krüppel-type zinc finger repressor normally expressed in germinal center B cells. However, CD23 expression is known to be down-regulated in plasma cells despite high level expression of IRF-4 and the lack of BCL-6, suggesting that in plasma cells the IRF-4-mediated induction of CD23 is prevented by its interaction with a distinct repressor. In this set of studies, we demonstrate that IRF-4 interacts with B lymphocyte-induced maturation protein/positive regulatory domain I-binding factor 1 (Blimp1/PRD1-BF1), a Krüppel-type zinc finger protein whose expression correlates with terminal B cell differentiation. Functional studies indicate that Blimp1, like BCL-6, can block IRF-4-transactivating ability. These findings thus support a model whereby IRF-4 function is modulated in a stage-specific manner by its interaction with developmentally restricted sets of Krüppel-type zinc finger proteins.
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1979
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Gupta S, Stravitz RT, Dent P, Hylemon PB. Down-regulation of cholesterol 7alpha-hydroxylase (CYP7A1) gene expression by bile acids in primary rat hepatocytes is mediated by the c-Jun N-terminal kinase pathway. J Biol Chem 2001; 276:15816-22. [PMID: 11278771 DOI: 10.1074/jbc.m010878200] [Citation(s) in RCA: 257] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Cholesterol 7alpha-hydroxylase (CYP7A1), the rate-limiting enzyme in the neutral pathway of bile acid biosynthesis, is feedback-inhibited at the transcriptional level by hydrophobic bile acids. Recent studies show that bile acids are physiological ligands for farnesoid X receptor (FXR). Activated FXR indirectly represses CYP7A1 transcription through induction of small heterodimer protein (SHP-1). In this study, we provide evidence that bile acids rapidly down-regulate CYP7A1 transcription via activation of the JNK/c-Jun pathway. Furthermore, we demonstrate that SHP-1 is also a direct target of activated c-Jun. In primary rat hepatocyte cultures, taurocholate (TCA) strongly activated JNK in a time- and concentration-dependent manner. Tumor necrosis factor-alpha, a potent activator of JNK, also rapidly activated JNK and down-regulated CYP7A1 mRNA levels. Overexpression of dominant-negative JNK1 or a transactivating domain mutant of c-Jun significantly blocked the ability of TCA to down-regulate CYP7A1 mRNA. In contrast, overexpression of wild-type c-Jun (c-Jun(wt)) enhanced the repression of CYP7A1 by TCA. Moreover, overexpression of c-Jun(wt) resulted in increased SHP-1 promoter activity. Mutation of a putative AP-1 (c-Jun) element suppressed c-Jun-mediated activation of the SHP-1 promoter construct. These results indicate that the bile acid-activated JNK pathway plays a pivotal role in regulating CYP7A1 levels in primary rat hepatocytes.
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1980
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Srivastava M, Ahmad N, Gupta S, Mukhtar H. Involvement of Bcl-2 and Bax in photodynamic therapy-mediated apoptosis. Antisense Bcl-2 oligonucleotide sensitizes RIF 1 cells to photodynamic therapy apoptosis. J Biol Chem 2001; 276:15481-8. [PMID: 11278320 DOI: 10.1074/jbc.m006920200] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Photodynamic therapy (PDT), a promising treatment modality, is an oxidative stress that induces apoptosis in many cancer cells in vitro and tumors in vivo. Understanding the mechanism(s) involved in PDT-mediated apoptosis may improve its therapeutic efficacy. Although studies suggest the involvement of multiple pathways, the triggering event(s) responsible for PDT-mediated apoptotic response is(are) not clear. To investigate the role of Bcl-2 in PDT-mediated apoptosis, we employed Bcl-2-antisense and -overexpression approaches in two cell types differing in their responses toward PDT apoptosis. In the first approach, we treated radiation-induced fibrosarcoma (RIF 1) cells, which are resistant to silicon phthalocyanine (Pc 4)-PDT apoptosis, with Bcl-2-antisense oligonucleotide. This treatment resulted in sensitization of RIF 1 cells to PDT-mediated apoptosis as demonstrated by i) cleavage of poly(ADP-ribose) polymerase, ii) DNA ladder formation, iii) terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL)-positive cells, and iv) DEVDase activity. This treatment also resulted in oligonucleotide concentration-dependent decrease in cell viability and down-regulation of Bcl-2 protein with a concomitant increase in apoptosis. However, the level of Bax, a pro-apoptotic member of Bcl-2 family, remained unaltered. In the second approach, an overexpression of Bcl-2 in PDT apoptosis-sensitive human epidermoid carcinoma (A431) cells resulted in enhanced apoptosis and up-regulation of Bax following PDT. In both the approaches, the increased Bax/Bcl-2 ratio was associated with an increased apoptotic response of PDT. Our data also demonstrated that PDT results in modulation of other Bcl-2 family members in a way that the overall ratio of pro-apoptotic and anti-apoptotic member proteins favors apoptosis.
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1981
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Gupta S. Upper gastrointestinal toxicity of rofecoxib and naproxen. N Engl J Med 2001; 344:1398; author reply 1398-9. [PMID: 11336057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
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1982
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Gupta S, Pasha S, Gupta YK, Bhardwaj DK. Effects of intracerebroventricularly administered chimeric peptide of metenkephalin and FMRFa--[D-Ala2]YFa-on antinociception and its modulation in mice. Brain Res Bull 2001. [PMID: 11427337 DOI: 10.1016/s0361-9230(01)00490-7]] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
An enzymatically stable analog of YGGFMKKKFMRFamide (YFa), a chimeric peptide of metenkephalin and FMRFa, was synthesised. The antinociceptive effects of intracerebroventricular injections of this analog-[D-Ala2)]YAGFMKKKFMRFamide ([D-Ala2]YFa)-was then investigated using the mouse radiant-heat tail-flick test. [D-Ala2]YFa produced modest to good antinociception at 1, 2, and 5 microg/mouse (0.64, 1.28, and 3.22 nmol, respectively). This antinociceptive effect was completely reversed by the opioid receptor antagonist naloxone (1.5 microg/mouse: 4.12 nmol, intracerebroventricular [i.c.v.]), administered 5 min prior. Pretreatment (5 min) with either neuropeptides FF (1 microg/mouse: 0.92 nmol, i.c.v.) or FMRFa (1 microg/mouse: 1.69 nmol, i.c.v.) significantly attenuated the antinociceptive effects induced by [D-Ala2]YFa (1 microg/mouse, i.c.v.). Intracerebroventricular administration of [D-Ala2]YFa at 1 microg/mouse dose with morphine (2 microg/mouse: 5.86 nmol, i.c.v.) produced an additive antinociceptive effect, suggesting that [D-Ala2]YFa may have a modulatory effect on opioid (morphine) analgesia. These results provide further support for a role of such amphiactive sequences in antinociception and its modulation.
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1983
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Gupta S, Arora K, Sampath A, Singh SS, Gupta A, Chaudhary VK. Mapping of hiv-1 Gag epitopes recognized by polyclonal antibodies using gene-fragment phage display system. Prep Biochem Biotechnol 2001; 31:185-200. [PMID: 11426705 DOI: 10.1081/pb-100103383] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Phage display has emerged as a powerful technique for mapping epitopes recognised by monoclonal and polyclonal antibodies. We have recently developed a simple gene-fragment phage display system and have shown its utility in mapping epitope recognised by a monoclonal antibody. In the present study, we have employed this system in mapping epitopes recognised by polyclonal antibodies raised against HIV-1 capsid protein, p24 which is derived from proteolytic cleavage of Gag polyprotein. HIV-1 gag DNA was fragmented by DNase I and the fragments (50-250 bp) were cloned into gene-fragment phage display vector to construct a library of phages displaying peptides. This phage library was used for affinity selection of phages displaying epitopes recognised by rabbit anti-p24 polyclonal antibodies. Selected phages contained sequences from two discrete regions of p24, demonstrating the presence of two antigenic regions. The DNA sequences encoding these regions were also cloned and expressed as GST fusion proteins. The immunoreactivity of these epitopes as GST fusion proteins, or as phage-displayed peptides, was comparable in ELISA system using same anti-p24 polyclonal antibodies. The results indicate that the gene-fragment based phage display system can be used efficiently to identify epitopes recognised by polyclonal antibodies, and phage displayed epitopes can be directly employed in ELISA to detect antibodies.
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1984
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Gupta S, Dash SC, Bhowmik D, Mohanty NK, Agarwal SK, Tiwari SC. Losartan use in mild to moderate hypertension--adverse effects in moderate to severe renal failure. THE JOURNAL OF THE ASSOCIATION OF PHYSICIANS OF INDIA 2001; 49:591. [PMID: 11361289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/16/2023]
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1985
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Gupta S, Pasha S, Gupta YK, Bhardwaj DK. Effects of intracerebroventricularly administered chimeric peptide of metenkephalin and FMRFa--[D-Ala2]YFa-on antinociception and its modulation in mice. Brain Res Bull 2001; 55:51-7. [PMID: 11427337 DOI: 10.1016/s0361-9230(01)00490-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
An enzymatically stable analog of YGGFMKKKFMRFamide (YFa), a chimeric peptide of metenkephalin and FMRFa, was synthesised. The antinociceptive effects of intracerebroventricular injections of this analog-[D-Ala2)]YAGFMKKKFMRFamide ([D-Ala2]YFa)-was then investigated using the mouse radiant-heat tail-flick test. [D-Ala2]YFa produced modest to good antinociception at 1, 2, and 5 microg/mouse (0.64, 1.28, and 3.22 nmol, respectively). This antinociceptive effect was completely reversed by the opioid receptor antagonist naloxone (1.5 microg/mouse: 4.12 nmol, intracerebroventricular [i.c.v.]), administered 5 min prior. Pretreatment (5 min) with either neuropeptides FF (1 microg/mouse: 0.92 nmol, i.c.v.) or FMRFa (1 microg/mouse: 1.69 nmol, i.c.v.) significantly attenuated the antinociceptive effects induced by [D-Ala2]YFa (1 microg/mouse, i.c.v.). Intracerebroventricular administration of [D-Ala2]YFa at 1 microg/mouse dose with morphine (2 microg/mouse: 5.86 nmol, i.c.v.) produced an additive antinociceptive effect, suggesting that [D-Ala2]YFa may have a modulatory effect on opioid (morphine) analgesia. These results provide further support for a role of such amphiactive sequences in antinociception and its modulation.
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1986
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Basu A, Mahata J, Gupta S, Giri AK. Genetic toxicology of a paradoxical human carcinogen, arsenic: a review. Mutat Res 2001; 488:171-94. [PMID: 11344043 DOI: 10.1016/s1383-5742(01)00056-4] [Citation(s) in RCA: 177] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Arsenic is widely distributed in nature in air, water and soil in the form of either metalloids or chemical compounds. It is used commercially, as pesticide, wood preservative, in the manufacture of glass, paper and semiconductors. Epidemiological and clinical studies indicate that arsenic is a paradoxical human carcinogen that does not easily induce cancer in animal models. It is one of the toxic compounds known in the environment. Intermittent incidents of arsenic contamination in ground water have been reported from several parts of the world. Arsenic containing drinking water has been associated with a variety of skin and internal organ cancers. The wide human exposure to this compound through drinking water throughout the world causes great concern for human health. In the present review, we have attempted to evaluate and update the mutagenic and genotoxic effects of arsenic and its compounds based on available literature.
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1987
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Samaiya A, Gupta S, Chumber S, Kashyap R, Dewanda NK, Vashisht S, Choudhry VP. Blunt abdominal trauma with delayed rupture of splenic haematoma in a haemophiliac patient. Haemophilia 2001; 7:331-4. [PMID: 11380639 DOI: 10.1046/j.1365-2516.2001.00499.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
A 13-year-old haemophilia A patient presented with pain in the abdomen, 4 days after a blunt abdominal trauma. The computed tomography scan of the abdomen showed a large splenic haematoma. The patient was initially managed with factor VIII replacement therapy, but 4 weeks later he had a delayed rupture of the splenic haematoma with haemoperitoneum and shock. An elective splenectomy under factor VIII therapy was successfully performed.
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1988
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Masand PS, Ashton AK, Gupta S, Frank B. Sustained-release bupropion for selective serotonin reuptake inhibitor-induced sexual dysfunction: a randomized, double-blind, placebo-controlled, parallel-group study. Am J Psychiatry 2001; 158:805-7. [PMID: 11329407 DOI: 10.1176/appi.ajp.158.5.805] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
OBJECTIVE The authors compared low-dose sustained-release bupropion with placebo for sexual dysfunction induced by selective serotonin reuptake inhibitors (SSRIs). METHOD Thirty adults who had received SSRIs for at least 6 weeks, who were euthymic, and who had sexual dysfunction as determined by a total score greater than 19 out of a possible 30 on the Arizona Sexual Experience Scale were randomly assigned to receive either 150 mg/day of sustained-release bupropion or placebo at 6:00 p.m. for 3 weeks. RESULTS There were no significant differences between the sustained-release bupropion and placebo groups as measured by change in Arizona Sexual Experiences Scale or Hamilton Depression Rating Scale scores or side effects. CONCLUSIONS Future studies should compare higher doses of bupropion for treating sexual dysfunction and should include a greater number of subjects.
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1989
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Gupta S, Kumar B. Intralesional cryosurgery using lumbar puncture and/or hypodermic needles for large, bulky, recalcitrant keloids. Int J Dermatol 2001; 40:349-53. [PMID: 11555001 DOI: 10.1046/j.1365-4362.2001.01117.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Keloids are notoriously difficult to treat. A variety of treatment modalities are currently in use, indicating that none is totally satisfactory. Surface cryosurgery is effective for smaller keloids, but not for larger ones. It often results in widespread depigmentation over the surface of the keloids, which may not be desirable, especially in patients with dark skin. OBJECTIVES To determine the efficacy of intralesional (IL) cryosurgery in large, bulky keloids unresponsive to IL steroids, and to observe the extent of depigmentation and other complications produced by the technique. METHODS Twelve patients with large, bulky, symptomatic keloids unresponsive to at least five injections of IL triamcinolone acetonide were included in the study. The age of the patients and the duration of the keloids were in the range 19-50 years and 1-12 years, respectively. The IL cryosurgery device was assembled using a small liquid nitrogen Dewar cylinder, a rubber and a plastic tube taken from a drip-set, adhesive tape, and hypodermic and lumbar puncture needles. The lumbar puncture or injection needle was introduced through the lesion until it appeared at the other side. Liquid nitrogen was then passed through the needle. The freezing time was between 20 and 30 s. The procedure was repeated for a second freeze-thaw cycle in the same session. RESULTS The patients underwent a minimum of five up to a maximum of 10 sessions of IL cryosurgery. Seven out of 12 patients showed > 75% flattening. Depigmentation was observed along the tracks of the needles in all the patients, which improved during follow-up due to pigment spread from the normally pigmented areas in between. At the end of follow-up, 1-25% of the area remained hypo- or depigmented in four patients, 26-50% in six patients, and 51-75% in the remaining two patients. CONCLUSIONS IL cryosurgery should be the preferred mode of therapy for large, bulky keloids, which are unresponsive to IL steroids.
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1990
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1991
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Reddy PR, Patni A, Sharma A, Gupta S, Tiwary AK. Effect of 2',4'-dichlorobenzamil hydrochloride, a Na(+)-Ca(2+) exchange inhibitor, on human spermatozoa. Eur J Pharmacol 2001; 418:153-5. [PMID: 11334878 DOI: 10.1016/s0014-2999(01)00892-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The present study is aimed to investigate the contact spermicidal efficacy of 2',4'-dichlorobenzamil hydrochloride (DBZ), a Na(+)-Ca(2+) exchange inhibitor, on ejaculated human spermatozoa. The drug produced a dose- and time-dependent spermicidal action on human spermatozoa. A concentration of 4 mM produced total loss of sperm viability within 1 min of addition to total semen. On the other hand, a similar action on spermatozoa separated from semen was noted at 0.5 mM concentration. The loss of spermatozoal viability was accompanied with an increase in intracellular Ca(2+). Sperm revival testing with glucose suggested a spermicidal rather than a spermiostatic action.
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1992
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Abstract
BACKGROUND Epidemiologic studies suggest that populations that consume large amounts of dietary fat are at greater risk for prostate carcinoma. Arachidonic acid and its precursor, linoleic acid, are major ingredients of animal fats and many vegetable oils that are used in the regions where prostate carcinoma is prevalent. The metabolism of arachidonic acid by either the cyclooxygenase pathway or the lipoxygenase pathway generates eicosanoids, which have been implicated in the pathogenesis of a variety of human diseases, including cancer, and are now believed to play important roles in tumor promotion, progression, and metastasis. Studying these pathways in specimens from patients with prostate carcinoma, the authors recently demonstrated the overexpression of cyclooxygenase-2 in prostate adenocarcinoma. In the current study, the authors report the overexpression of lipoxygenase-5 (5-LO) in samples from patients with prostate adenocarcinoma. METHODS Employing 22 pair-matched benign and malignant tissue samples that were obtained from the same patients with prostate carcinoma, the expression of 5-LO was determined using reverse transcriptase-polymerase chain reaction, immunoblotting, and immunohistochemistry and by measuring the levels of 5-hydroxyeicosatetraenoic acid (5-HETE) by radioimmunoassay. RESULTS The mean level of 5-LO mRNA was six-fold greater (P < 0.001) in malignant tissue compared with benign tissue. The immunoblot analysis demonstrated that, compared with benign tissue, 5-LO protein was overexpressed in 16 of 22 samples examined and was 2.6 fold greater (P < 0.001) in malignant tissue. Immunohistochemical studies further verified 5-LO up-regulation in malignant tissue that was not present in benign tissue. The levels of 5-HETE, which is a metabolic product of arachidonic acid, was found to be 2.2-fold greater (P < 0.001) in malignant tumor tissue compared with benign tissue. CONCLUSIONS To the authors' knowledge, this is the first in vivo study showing overexpression of 5-LO in patients with prostate carcinoma. This study suggests that inhibitors of arachidonic acid pathway in general and selective 5-LO inhibitors in particular may be useful for prevention or therapy in patients with prostate carcinoma.
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1993
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Abstract
BACKGROUND Epidemiologic studies suggest that populations that consume large amounts of dietary fat are at greater risk for prostate carcinoma. Arachidonic acid and its precursor, linoleic acid, are major ingredients of animal fats and many vegetable oils that are used in the regions where prostate carcinoma is prevalent. The metabolism of arachidonic acid by either the cyclooxygenase pathway or the lipoxygenase pathway generates eicosanoids, which have been implicated in the pathogenesis of a variety of human diseases, including cancer, and are now believed to play important roles in tumor promotion, progression, and metastasis. Studying these pathways in specimens from patients with prostate carcinoma, the authors recently demonstrated the overexpression of cyclooxygenase-2 in prostate adenocarcinoma. In the current study, the authors report the overexpression of lipoxygenase-5 (5-LO) in samples from patients with prostate adenocarcinoma. METHODS Employing 22 pair-matched benign and malignant tissue samples that were obtained from the same patients with prostate carcinoma, the expression of 5-LO was determined using reverse transcriptase-polymerase chain reaction, immunoblotting, and immunohistochemistry and by measuring the levels of 5-hydroxyeicosatetraenoic acid (5-HETE) by radioimmunoassay. RESULTS The mean level of 5-LO mRNA was six-fold greater (P < 0.001) in malignant tissue compared with benign tissue. The immunoblot analysis demonstrated that, compared with benign tissue, 5-LO protein was overexpressed in 16 of 22 samples examined and was 2.6 fold greater (P < 0.001) in malignant tissue. Immunohistochemical studies further verified 5-LO up-regulation in malignant tissue that was not present in benign tissue. The levels of 5-HETE, which is a metabolic product of arachidonic acid, was found to be 2.2-fold greater (P < 0.001) in malignant tumor tissue compared with benign tissue. CONCLUSIONS To the authors' knowledge, this is the first in vivo study showing overexpression of 5-LO in patients with prostate carcinoma. This study suggests that inhibitors of arachidonic acid pathway in general and selective 5-LO inhibitors in particular may be useful for prevention or therapy in patients with prostate carcinoma.
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1994
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Gupta S, Srivastava M, Ahmad N, Sakamoto K, Bostwick DG, Mukhtar H. Lipoxygenase-5 is overexpressed in prostate adenocarcinoma. Cancer 2001. [PMID: 11241241 DOI: 10.1002/1097-0142(20010215)91:4<737::aid-cncr1059>3.0.co;2-f] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
BACKGROUND Epidemiologic studies suggest that populations that consume large amounts of dietary fat are at greater risk for prostate carcinoma. Arachidonic acid and its precursor, linoleic acid, are major ingredients of animal fats and many vegetable oils that are used in the regions where prostate carcinoma is prevalent. The metabolism of arachidonic acid by either the cyclooxygenase pathway or the lipoxygenase pathway generates eicosanoids, which have been implicated in the pathogenesis of a variety of human diseases, including cancer, and are now believed to play important roles in tumor promotion, progression, and metastasis. Studying these pathways in specimens from patients with prostate carcinoma, the authors recently demonstrated the overexpression of cyclooxygenase-2 in prostate adenocarcinoma. In the current study, the authors report the overexpression of lipoxygenase-5 (5-LO) in samples from patients with prostate adenocarcinoma. METHODS Employing 22 pair-matched benign and malignant tissue samples that were obtained from the same patients with prostate carcinoma, the expression of 5-LO was determined using reverse transcriptase-polymerase chain reaction, immunoblotting, and immunohistochemistry and by measuring the levels of 5-hydroxyeicosatetraenoic acid (5-HETE) by radioimmunoassay. RESULTS The mean level of 5-LO mRNA was six-fold greater (P < 0.001) in malignant tissue compared with benign tissue. The immunoblot analysis demonstrated that, compared with benign tissue, 5-LO protein was overexpressed in 16 of 22 samples examined and was 2.6 fold greater (P < 0.001) in malignant tissue. Immunohistochemical studies further verified 5-LO up-regulation in malignant tissue that was not present in benign tissue. The levels of 5-HETE, which is a metabolic product of arachidonic acid, was found to be 2.2-fold greater (P < 0.001) in malignant tumor tissue compared with benign tissue. CONCLUSIONS To the authors' knowledge, this is the first in vivo study showing overexpression of 5-LO in patients with prostate carcinoma. This study suggests that inhibitors of arachidonic acid pathway in general and selective 5-LO inhibitors in particular may be useful for prevention or therapy in patients with prostate carcinoma.
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1995
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Ganapati U, Gupta S, Radha V, Sudhakar C, Manogaran PS, Swarup G. A nuclear protein tyrosine phosphatase induces shortening of G1 phase and increase in c-Myc protein level. Exp Cell Res 2001; 265:1-10. [PMID: 11281638 DOI: 10.1006/excr.2001.5158] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
PTP-S2 is a ubiquitously expressed nuclear protein tyrosine phosphatase which shows increased expression upon mitogenic stimulation in a variety of cells in vitro and in vivo. In order to understand the role of this enzyme in cell cycle progression, tetracycline-regulated HeLa clones expressing PTP-S2 were isolated and characterized. Tetracycline-controlled expression of PTP-S2 increased the rate of cell proliferation. An analysis of the distribution of cells in various phases of the cell cycle in an exponentially growing cell population showed that there was a large decrease in the percentage of cells in G1 phase in a PTP-S2-expressing population of cells compared to nonexpressing cells. This decrease in the percentage of cells in G1 was dependent on the level of PTP-S2 expression. There was a corresponding increase in the percentage of cells in G2/M but no significant increase in the percentage of cells in S phase. An analysis of the time course of cell cycle progression after release from double thymidine block showed that the duration of G1 phase was significantly shortened in cells induced to express exogenous PTP-S2. However, the duration of S phase was not significantly altered and the duration of G2 phase was increased to some extent. Induction of PTP-S2 expression was associated with an increase in c-Myc protein levels, although the c-Myc mRNA level was not changed. Our results suggest that overexpression of PTP-S2 promotes progression of cells through G1 to S phase and is associated with increased level of c-Myc protein through a posttranscriptional mechanism.
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1996
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Gupta S, Radha V, Furukawa Y, Swarup G. Direct transcriptional activation of human caspase-1 by tumor suppressor p53. J Biol Chem 2001; 276:10585-8. [PMID: 11278253 DOI: 10.1074/jbc.c100025200] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The tumor suppressor protein p53 is a sequence-specific DNA-binding protein, and its biological responses are very often mediated by transcriptional activation of various target genes. Here we show that caspase-1 (interleukin-1beta converting enzyme), which plays a role in the production of proinflammatory cytokines and in apoptosis, is a transcriptional target of p53. Caspase-1 mRNA levels increased upon overexpression of p53 by transfection in MCF-7 cells. Human caspase-1 promoter showed a sequence homologous to the consensus p53-binding site. This sequence bound to p53 in gel shift assays. A caspase-1 promoter-reporter construct was activated 6-8-fold by cotransfection with normal p53 but not by mutant p53 (His(273)) in HeLa, as well as MCF-7, cells. Mutation of the p53-binding site in caspase-1 promoter abolished transactivation by p53. Treatment of p53-positive MCF-7 cells with the DNA-damaging drug, doxorubicin, which increases p53 levels, enhanced caspase-1 promoter activity 4-5-fold, but similar treatment of MCF-7-mp53 (a clone of MCF-7 cells expressing mutant p53) and p53-negative HeLa cells with doxorubicin did not increase caspase-1 promoter activity. Doxorubicin treatment increased caspase-1 mRNA levels in MCF-7 cells but not in MCF-7-mp53 or HeLa cells. These results show that endogenous p53 can regulate caspase-1 gene expression.
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1997
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Gupta S, Arora K, Gupta A, Chaudhary VK. Gag-derived proteins of HIV-1 isolates from Indian patients: cloning, expression, and purification of p17 of B- and C-subtypes. Protein Expr Purif 2001; 21:378-85. [PMID: 11281711 DOI: 10.1006/prep.2001.1389] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A simple and efficient method for expression in Escherichia coli and purification of matrix protein, p17, of human immunodeficiency virus type 1 (HIV-1) of both B- and C-subtypes is described. DNA sequences encoding p17 of B- and C-subtype were cloned from respective gag sequences. The gag sequences were obtained by PCR amplification using DNA extracted from peripheral blood lymphocytes of an HIV-1 infected patient from India. A T7-promoter-based expression system was optimized for expression of p17 in soluble form. p17 (B- and C-subtype) was purified to near homogeneity using conventional chromatographic techniques. Purification of p17 (C-subtype) is described for the first time with yield of 7.7 mg from a 1-liter culture. The yield of p17 (B-subtype) is 14.7 mg from a 1-liter culture, which is severalfold better than that reported earlier. N-terminal sequencing and CD spectra of the purified proteins, p17B and p17C, show that the proteins are properly processed and well-folded. The immunoreactivity of both types of p17 to sera from HIV-infected individuals is comparable.
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1998
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Murthy GV, Ellwein LB, Gupta S, Tanikachalam K, Ray M, Dada VK. A population-based eye survey of older adults in a rural district of Rajasthan: II. Outcomes of cataract surgery. Ophthalmology 2001; 108:686-92. [PMID: 11297484 DOI: 10.1016/s0161-6420(00)00578-9] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE To assess the outcomes of cataract surgery in rural northwest India. DESIGN Population-based, cross-sectional study. PARTICIPANTS A total of 549 cataract-operated persons (723 operated eyes). METHODS Cluster sampling was used in randomly selecting a cross-sectional sample of persons 50 years of age or older for visual acuity measurement, refraction, and slit-lamp and direct ophthalmoscope examination early in 1999. Those operated on for cataract were queried as to the date and place of surgery. The principal cause of reduced vision was identified for all examined eyes with presenting visual acuity worse than 6/18. MAIN OUTCOME MEASURES Presenting and best-corrected visual acuity and cause of vision loss. RESULTS Presenting visual acuity was less than 6/60 in the better eye in 33.7% of cataract-operated persons and greater than or equal to 6/18 in both eyes in 8.2%; 31.7% were bilaterally operated on. Of cataract-operated eyes, 44.1% initially had visual acuity less than 6/60 and 31.5% greater than or equal to 6/18; with best correction, the corresponding percentages were 14.0% and 61.5%. Intracapsular cataract extraction was used in 92% of cases, and 66% had been operated on in surgery camps. Surgical complications were common and a major cause of vision impairment. In multiple logistic regression modeling, female gender and residence in a rural area were associated negatively with both presenting and best-corrected visual acuity outcomes, and surgery conducted before 1990 was associated negatively with best-corrected visual acuity. Place of surgery and subject schooling were not associated with vision outcomes. CONCLUSIONS Cataract surgery subjects in rural areas of India that are without adequately equipped facilities and skilled surgeons, and lack of availability of intraocular lenses, are not realizing the full sight-restoring potential of modern-day surgery. Emphasis on the quality of cataract surgery outcomes must be increased to keep pace with that being given to increasing surgical volume.
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1999
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Gupta S, Handa U, Handa S, Mohan H. The efficacy of electrosurgery and excision in treating patients with multiple apocrine hidrocystomas. Dermatol Surg 2001; 27:382-4. [PMID: 11298711 DOI: 10.1046/j.1524-4725.2001.00210.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Apocrine hidrocystomas are adenomatous cystic proliferations of the apocrine glands. They typically occur as solitary lesions, though rarely may occur as multiple lesions. Management of multiple hidrocystomas can be difficult, particularly if they are large. Surgical modalities may be required for effective therapy. OBJECTIVE To compare the results of electrosurgery and excision in treating multiple apocrine hidrocystomas. METHODS A 50-year-old man presented with multiple apocrine hidrocystomas ranging in size from 1 to 12 mm. The lesions were located over the periorbital skin, cheeks, and pinnae. Excision and electrodessication were utilized for therapy. At a 1-year follow-up, the patient was evaluated for recurrences and cosmetic result. RESULTS There were no recurrences until 1 year after surgery. In the areas treated with electrodessication, no visible scars were identified. In the areas treated with excision, localized scars were observed. CONCLUSIONS Both electrodessiation and excision are effective therapies for multiple apocrine hidrocystomas. We suggest that tumors less than 1 cm be treated with electrodessication and lesions greater than 1 cm with excision.
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2000
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Singh HP, Gupta S, Raju GM, Kochupillai V. Redefining 'self': the role of microflora (commensals) mismatch in the development of GvHD after allogeneic stem cell transplantation and some possible remedies. Med Hypotheses 2001; 56:448-50. [PMID: 11339845 DOI: 10.1054/mehy.2000.1197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The discovery of human leukocyte antigen (HLA) molecules and their role in allorecognition has facilitated the initiation of allogeneic stem cell transplantation in human beings. HLA mismatch to a large extent explains the phenomenon of graft rejection and graft versus host disease (GvHD). Incidence of GvHD even in syngeneic transplants suggests a role for extra genetic factors in the causation of GvHD. We hereby propose a hypothesis that the definition of 'self' (in the immunological sense) should be broadened to include both genetically determined molecules (e.g. HLA) and the microbial flora that colonize an individual. This hypothesis explains several observations about GvHD which can not fully be accounted for by the HLA mismatch theory and gives some clues towards circumventing GvHD.
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