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Abstract
BACKGROUND Congenital hepatic fibrosis (CHF) is an uncommon cause of portal hypertension in children. So far, there is no report of this from the subcontinent. We have studied the clinical spectrum of CHF in North Indian children. METHODS Fifteen children were diagnosed with CHF on the basis of their liver histology over a period of 6.5 years. Their clinical details were recorded. Oesophagogastroduodenoscopy and abdominal ultrasonography were performed in all cases. All siblings were examined clinically; and ultrasonography, endoscopy and liver biopsy were performed if there was firm hepatomegaly. Children with variceal bleeding were managed by endoscopic sclerotherapy. The median age of these children was 8 years with a male to female ratio of 1.5:1. RESULTS Only one sibling (of 33) was diagnosed as having CHF. The predominant presentations were variceal bleeding in six, abdominal distension in seven and incidental detection of organomegaly in two. Hepatomegaly was present in all patients and splenomegaly in all but one. Liver function and renal function tests were normal in all children, except for a raised serum alkaline phosphatase in six. Two children had associated renal cysts, two had choledochal cysts, one each had Caroli's disease and biliary atresia and two children had portal vein thrombosis. Variceal obliteration was achieved in five children after an average 4.8 sclerotherapy sessions and one required a mesocaval shunt. On follow up (median 41 months, range 1-80 months) all are doing well. CONCLUSIONS Congenital hepatic fibrosis is mainly sporadic in India and associated renal lesions are uncommon. Endoscopic sclerotherapy is effective in controlling variceal bleed and the prognosis is universally good in the absence of renal diseases.
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Abstract
Fine-needle aspiration was performed on an orbital mass in a 53-yr-old woman. The cytologic diagnosis was meningioma, which was later confirmed by histologic study of biopsy material. The cytologic features of the aspirated material (nuclear pseudoinclusions, psammoma bodies, and cells arranged in syncytial sheets and whorls) allowed a rapid, reliable, outpatient diagnosis to be formulated. The cytologic features are discussed and the literature is reviewed. Diagn. Cytopathol. 1999;21:402-404.
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653
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Communal C, Singh K, Sawyer DB, Colucci WS. Opposing effects of beta(1)- and beta(2)-adrenergic receptors on cardiac myocyte apoptosis : role of a pertussis toxin-sensitive G protein. Circulation 1999; 100:2210-2. [PMID: 10577992 DOI: 10.1161/01.cir.100.22.2210] [Citation(s) in RCA: 380] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
BACKGROUND beta-Adrenergic receptor (beta-AR) stimulation increases apoptosis in adult rat cardiac (ventricular) myocytes (ARVMs) via activation of adenylyl cyclase. beta(2)-ARs may couple to a G(i)-mediated signaling pathway that can oppose the actions of adenylyl cyclase. METHODS AND RESULTS In ARVMs, beta-AR stimulation for 24 hours increased the number of apoptotic cells as measured by flow cytometry. beta-AR-stimulated apoptosis was abolished by the beta(1)-AR-selective antagonist CGP 20712A (P<0.05 versus beta-AR stimulation alone) but was potentiated by the beta(2)-AR-selective antagonist ICI 118,551 (P<0.05 versus beta-AR stimulation alone). The muscarinic agonist carbachol also prevented beta-AR-stimulated apoptosis (P<0.05 versus beta-AR stimulation alone), whereas pertussis toxin potentiated the apoptotic action of beta-AR stimulation (P<0.05 versus beta-AR stimulation alone) and prevented the antiapoptotic action of carbachol. CONCLUSIONS In ARVMs, stimulation of beta(1)-ARs increases apoptosis via a cAMP-dependent mechanism, whereas stimulation of beta(2)-ARs inhibits apoptosis via a G(i)-coupled pathway. These findings have implications for the pathophysiology and treatment of myocardial failure.
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MESH Headings
- Adenylate Cyclase Toxin
- Adrenergic beta-Agonists/pharmacology
- Adrenergic beta-Antagonists/pharmacology
- Animals
- Apoptosis/drug effects
- Carbachol/pharmacology
- Cardiotonic Agents/pharmacology
- Cyclic AMP/metabolism
- GTP-Binding Protein alpha Subunits, Gi-Go/antagonists & inhibitors
- Heart/drug effects
- Imidazoles/pharmacology
- Isoproterenol/pharmacology
- Male
- Muscarinic Agonists/pharmacology
- Myocardium/cytology
- Pertussis Toxin
- Prazosin/pharmacology
- Propanolamines/pharmacology
- Rats
- Rats, Sprague-Dawley
- Receptors, Adrenergic, beta-1/drug effects
- Receptors, Adrenergic, beta-1/physiology
- Receptors, Adrenergic, beta-2/drug effects
- Receptors, Adrenergic, beta-2/physiology
- Second Messenger Systems/drug effects
- Virulence Factors, Bordetella/pharmacology
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654
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Deakin AM, Singh K, Crowe JS, Ellis JH, Dalgleish A, Leicester RJ, Finlayson CJ, Miles WF, Life PF. A lack of evidence for down-modulation of CD3 zeta expression in colorectal carcinoma and pregnancy using multiple detection methods. Clin Exp Immunol 1999; 118:197-204. [PMID: 10540179 PMCID: PMC1905430 DOI: 10.1046/j.1365-2249.1999.01044.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/14/1999] [Indexed: 11/20/2022] Open
Abstract
Loss of the T cell receptor-associated CD3 zeta chain has been proposed as a possible mechanism of the acquired immunosuppression in both tumour-bearing hosts, and in symptomatic patients with HIV infection. However, other reports suggest that the zeta-chain loss may in part be caused by protease activity of contaminating phagocytes ex vivo. Using flow cytometry and Western blot analysis on highly purified T cells, and ensuring adequate addition of protease inhibitors, we have studied the expression of CD3zeta on peripheral blood T cells from patients with colorectal carcinoma, and compared these with normal controls, and pregnant donors, as a further example of an immunocompromised state. Immunohistochemistry was performed on tumour sections from patients with colorectal carcinoma to measure CD3zeta expression in tumour infiltrating T cells, and compared with normal mucosa and tonsil. Using these three approaches, our data provide no evidence for downregulation of CD3zeta chain expression either in colorectal carcinoma or pregnancy and suggest that this explanation is unlikely to fully account for the reduced T cell function associated with these conditions in all patients.
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655
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Singh K, Chakrabarti A, Narang A, Gopalan S. Yeast colonisation & fungaemia in preterm neonates in a tertiary care centre. Indian J Med Res 1999; 110:169-73. [PMID: 10680302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023] Open
Abstract
Seventy consecutive preterm neonates who stayed in the hospital for more than seven days between March and October 1996, were studied for colonisation at oral, umbilical, groin, and rectal areas and for fungaemia. Overall, 71.4 per cent of the neonates were colonised and colonisation occurred within 24 h in 38 per cent preterm neonates. Neonates weighing less than 1500 g were colonised more frequently at more than one site and had higher load of yeast. Candida albicans (19%), Pichia (Hansenula) anomala (17.5%), C. tropicalis (13.2%), C. parapsilosis (12.3%) and Trichosporon cutaneum (10.0%) were the predominant colonising yeasts. Fungaemia was detected in 22.8 per cent of preterm neonates with predominance of P. anomala fungaemia (62.5%). Prematurity, male sex, broad spectrum antibiotic therapy, intubation and higher colonising rate were identified as significant risk factors for development of fungaemia. Except one strain of C. tropicalis, all yeast strains were sensitive to commonly used systemic antifungal agents. Study highlights the importance of routine surveillance of yeast colonisation of preterm neonates with identifying possible risk factors.
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656
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Ho BC, Lee EH, Singh K. Epidemiology, presentation and management of congenital muscular torticollis. Singapore Med J 1999; 40:675-9. [PMID: 10709403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
AIM OF STUDY Congenital muscular torticollis is a condition of debatable aetiology and management. Untreated, cervical function and facial cosmesis may be severely compromised. The aim of this study was to establish the epidemiology, presentation and management of congenital muscular torticollis in Singapore. PATIENTS Ninety-one patients with torticollis were seen at the National University Hospital (NUH) from January 1994 to December 1997. Torticollis was first noted at a median age of 2 months with the median age of presentation being 6 months. At presentation, a sternomastoid tumour was noted in 33 patients and 62 patients had facial asymmetry. Thirteen of 22 patients with neonatal records available had mandibular hypoplasia at birth on the side where the sternomastoid was affected. Half of the patients (45) had a right sided lesion, with 46 being left sided. The rates of assisted breech delivery, instrumental deliveries (forceps and vacuum) and Caesarean section were higher in the study group. Nine (59.1%) of 13 patients with vertex presentation, had a lesion on the side of the presenting shoulder. Forty-eight of 72 patients responded well to therapy with improvement; 20 underwent surgery and the median age of presentation of 19.5 months in this group was significantly later than that of 4 months in the group which responded to physiotherapy alone. CONCLUSION Birth trauma appears to be the main aetiological factor in congenital muscular torticollis. Patients generally respond well to physiotherapy. This study revealed 2 findings hitherto unreported: (1) mandibular hypoplasia may be an useful early sign of this condition, and (2) the side affected may depend on the side of shoulder delivered first. More studies, however, are required to confirm these findings.
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657
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Melzer D, Watters L, Paykel E, Singh K, Gormley N. Factors explaining the use of psychiatric services by general practices. Br J Gen Pract 1999; 49:887-91. [PMID: 10818654 PMCID: PMC1313559] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023] Open
Abstract
BACKGROUND Referral rates from general practitioners to hospital services vary up to 25-fold, and several studies have sought reasons for this apparent inconsistency in clinical practice. However, few studies have concentrated on, or indeed included, psychiatric patients or psychiatric referral rates. AIM To determine the effect of population, general practice, and mental health service factors on use of specialist mental health services by general practices. METHOD Cross-sectional data from computerized records used in managing clinical care on all patients aged 16 to 64 years who had been in contact with any mental health service staff over a two-year period. Twenty-three practices in Huntingdon Health District were studied, with a list population of 87,643 patients aged 16 to 64 years, served by one inpatient ward and three community mental health teams. The main outcome measures were the relation between age-standardized utilization ratio and markers of morbidity, deprivation, community mental health provision, and practice prescribing. RESULTS Variation between practices in the use of mental health services was relatively limited, especially compared with the use of other secondary medical and surgical services. Three factors together explained 60.8% of the variance in use between practices: a census-based index of long-term limiting illness in females registered with the practice, use of one of the three community mental health teams, and average quarterly defined daily doses of hypnotics prescribed per practice population. Relatively high prescribing of hypnotics was associated with lower service use. CONCLUSION Population morbidity and factors in the mental health service explain a substantial part of the variation in the use of mental health services between practices. Further work is needed to replicate these findings and explore why team factors and prescribing patterns influence utilization ratios. This study underlines the importance of examining population, practice, and specialist service factors in explaining variation in the use of secondary care by general practices.
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658
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Singh K, Khanna AK, Chander R. Hepatoprotective activity of ellagic acid against carbon tetrachloride induced hepatotoxicity in rats. INDIAN JOURNAL OF EXPERIMENTAL BIOLOGY 1999; 37:1025-6. [PMID: 10783760] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
Administration of CCl4 to normal rats and consequent oral feeding with ellagic acid (50 mg/kg) provided a significant protection against the biochemical alterations in serum and liver produced by CCl4. In vitro experiments showed that liver microsomes from animals treated with ellagic acid and CCl4, decreased lipid peroxidation compared to microsome prepared from rats exposed to CCl4 alone.
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659
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Singh K. Healthy ageing. Indian J Psychiatry 1999; 41:381-3. [PMID: 21430817 PMCID: PMC2963849] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
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660
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Singh K, Fong YF, Prasad RN, Dong F. Evacuation interval after vaginal misoprostol for preabortion cervical priming: a randomized trial. Obstet Gynecol 1999; 94:431-4. [PMID: 10472873 DOI: 10.1016/s0029-7844(99)00272-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
OBJECTIVE To determine the optimal interval for evacuation after preabortion cervical priming with vaginal misoprostol. METHODS One hundred eighty healthy nulliparas requesting legal termination of pregnancy between 6 and 11 weeks' gestation were assigned randomly to receive 400, 600, or 800 microg of intravaginal misoprostol. Vacuum aspiration was done after 3 hours in the 400-microg group and after 2 hours in the 600- and 800-microg groups. The degree of cervical dilatation before operation was measured with a Hegar dilator. Preoperative and intraoperative blood loss and associated side effects were also assessed. RESULTS Eleven (18.3%) and 15 (25.0%) women in the 600-and 800-microg groups, respectively, had cervical dilatation of at least 8 mm after an interval of 2 hours; 55 (91.7%) women who received 400 microg for a 3-hour interval had similar cervical dilatation. Using 400 microg as a baseline, the odds ratio (OR) was 0.02; 95% confidence interval (CI) was 0.01, 0.06 for 600 microg and OR 0.03; 95% CI 0.01, 0.09 for 800 microg for achieving successful preabortion cervical dilatation of at least 8 mm. The mean cervical dilatation of 6.7 mm and 6.8 mm for the higher doses was also significantly less than that of 8.1 for the 400-microg dose (P<.001). The mean preoperative and intraoperative blood loss was only statistically different when the 400- and 800-microg groups were compared (P = .03). There were also significantly more side effects, namely abdominal pain and fever above 38.0 C, in the 600- and 800-microg groups (P<.001), compared with the 400-microg group. When the 600- and 800-microg groups were compared, there were still significantly more women complaining of abdominal pain (P<.001). None of the women in the study required analgesics for pain or antipyretics for fever. CONCLUSION The minimal evacuation interval should be at least 3 hours for successful preabortion cervical priming.
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661
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Singh K, Singh R, Parija SC. Unusual presentation of tuberculosis in an infant. Indian J Pediatr 1999; 66:813-4. [PMID: 10798144 DOI: 10.1007/bf02726276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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662
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Fong YF, Singh K. Medical treatment of a grossly enlarged adenomyotic uterus with the levonorgestrel-releasing intrauterine system. Contraception 1999; 60:173-5. [PMID: 10640162 DOI: 10.1016/s0010-7824(99)00075-x] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Adenomyosis is an important cause of menorrhagia. Besides hysterectomy, the treatment options for adenomyosis have been limited. Presented here is the successful treatment of adenomyosis in a woman presenting with menorrhagia, dysmenorrhea, and an enlarging uterus, for whom conservative therapy initiated with mefenamic acid was unsatisfactory. The patient had insertion of the levonorgestrel-releasing intrauterine system (LNG-IUS). A marked decrease in uterine size occurred within 12 months of insertion accompanied by resolution of the menorrhagia and dysmenorrhea. Thus, the LNG-IUS is a viable option and represents a real advance in the treatment of adenomyosis.
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663
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Singh K, Khanna AK, Visen PK, Chander R. Protective effect of ellagic acid on t-butyl hydroperoxide induced lipid peroxidation in isolated rat hepatocytes. INDIAN JOURNAL OF EXPERIMENTAL BIOLOGY 1999; 37:939-40. [PMID: 10687292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
Ellagic acid, a plant polyphenol, showed protective effect on isolated rat hepatocytes against destruction due to lipid peroxide formation induced by t-butyl hydroperoxide in vitro. Ellagic acid inhibited the generation of superoxide anions and hydroxyl radicals both in enzymic and non enzymic systems, thus providing protection against oxidative damage.
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664
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Singh K, Bahadur D. Characterization of SiO2-Na2O-Fe2O3-CaO-P2O5-B2O3 glass ceramics. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 1999; 10:481-484. [PMID: 15348116 DOI: 10.1023/a:1008949025635] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Bioactivity and magnetic properties were investigated in glass and glass ceramics based on the SiO2-Na2O-Fe2O3-CaO-P2O5-B2O3 system to find their suitability as thermoseed for hyperthermia treatment of cancer. The effect of change in compositions on bioactivity was examined in simulated body fluids. The glass ceramic samples exhibit Na3CaSi3O8 and Na3-XFeXPO4 phases. After dipping the glass ceramic samples in simulated body fluids silica hydrogel first forms, followed by an amorphous calcium phosphate layer. Magnetic and microwave resonance experiments further demonstrate the potential of these glass ceramics for possible use in hyperthermia.
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665
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Katyal R, Rana SV, Vaiphei K, Ohja S, Singh K, Singh V. Effect of rotavirus infection on small gut pathophysiology in a mouse model. J Gastroenterol Hepatol 1999; 14:779-84. [PMID: 10482428 DOI: 10.1046/j.1440-1746.1999.01948.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
AIM To study the effect of rotavirus infection on amino acid uptake in the small intestine in an experimental mouse model. METHODS Infant mice (7-8 days of age) were orally infected with the EB serotype 3 strain of rotavirus and animals (both infected and control) were killed on days 0, 1, 3, 5, 7 and 10 post inoculation (PI) after recording their bodyweights. Gamma-glutamyltranspeptidase (GGT), leucine amino peptidase (LAP), glutathione (GSH) and leucine amino acid uptake in the jejunum and ileum were assessed. RESULTS Infected animals showed significant reduction in their bodyweights and intestinal lengths on the third day PI compared with controls. Leucine amino peptidase, GGT, GSH and leucine uptake were significantly reduced in the ileum on the third and fifth day PI compared with controls while uptake in the jejunum was only reduced on third day PI. The LAP, GGTP, GSH and leucine uptake attained normal levels on the seventh day when diarrhoea stopped. Histology showed damage to the villi in the jejunum and prominent cytoplasmic vacuolation in the ileum of infected animals on the third and fifth day PI. CONCLUSION Rotavirus affects amino acid uptake in the small intestine at the time of peak infection.
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666
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Singh K, Phadke SR, Agarwal SS. Mandibulo-acral dysplasia: Indian patient with severe bony changes. THE JOURNAL OF THE ASSOCIATION OF PHYSICIANS OF INDIA 1999; 47:833-4. [PMID: 10778637] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
We report an Indian patient with mandibulo-acral dysplasia. This patient had absence of spinous processes of 4th and 5th cervical vertebrae and very severe bony changes but no loss of teeth.
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667
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Siwik DA, Tzortzis JD, Pimental DR, Chang DL, Pagano PJ, Singh K, Sawyer DB, Colucci WS. Inhibition of copper-zinc superoxide dismutase induces cell growth, hypertrophic phenotype, and apoptosis in neonatal rat cardiac myocytes in vitro. Circ Res 1999; 85:147-53. [PMID: 10417396 DOI: 10.1161/01.res.85.2.147] [Citation(s) in RCA: 191] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Oxidative stress has been implicated in the pathophysiology of myocardial failure. We tested the hypothesis that inhibition of endogenous antioxidant enzymes can regulate the phenotype of cardiac myocytes. Neonatal rat ventricular myocytes in vitro were exposed to diethyldithiocarbamic acid (DDC), an inhibitor of cytosolic (Cu, Zn) and extracellular superoxide dismutase (SOD). DDC inhibited SOD activity and increased intracellular superoxide in a concentration-dependent manner. A low concentration (1 micromol/L) of DDC stimulated myocyte growth, as demonstrated by increases in protein synthesis, cellular protein, prepro-atrial natriuretic peptide, and c-fos mRNAs and decreased sarcoplasmic reticulum Ca(2+)ATPase mRNA. These actions were all inhibited by the superoxide scavenger Tiron (4,5-dihydroxy-1,3-benzene disulfonic acid). Higher concentrations of DDC (100 micromol/L) stimulated myocyte apoptosis, as evidenced by DNA laddering, characteristic nuclear morphology, in situ terminal deoxynucleotidyl transferase-mediated nick end-labeling (TUNEL), and increased bax mRNA expression. DDC-stimulated apoptosis was inhibited by the SOD/catalase mimetic EUK-8. The growth and apoptotic effects of DDC were mimicked by superoxide generation with xanthine plus xanthine oxidase. Thus, increased intracellular superoxide resulting from inhibition of SOD causes activation of a growth program and apoptosis in cardiac myocytes. These findings support a role for oxidative stress in the pathogenesis of myocardial remodeling and failure.
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668
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Jin J, Kaushik N, Singh K, Modak MJ. Analysis of the role of glutamine 190 in the catalytic mechanism of murine leukemia virus reverse transcriptase. J Biol Chem 1999; 274:20861-8. [PMID: 10409628 DOI: 10.1074/jbc.274.30.20861] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
To determine the catalytic role of Gln(190), a member of the highly conserved LPQG motif in Moloney murine leukemia virus reverse transcriptase, we carried out site-directed mutagenesis of this residue to generate Q190N and Q190A. Both mutant proteins exhibited a significant loss in their polymerase and pyrophosphorolysis activities with a more pronounced effect noted with the Gln --> Asn substitution. The catalytic efficiencies of the mutants exhibited a 40-70-fold reduction with poly(rC) and poly(dC) templates in the presence of Mg(2+) and a 10-20-fold reduction with poly(rA) template in the presence of Mn(2+). Interestingly, the K(m) for NTP exhibited only a moderate 3-10-fold increase irrespective of the template-primer and the metal ion. Photoaffinity labeling of both the mutant and the WT enzymes exhibited an identical affinity for RNA.DNA and DNA.DNA template-primers. However, unlike the WT enzyme, the mutant enzymes exhibited a significantly reduced ability to catalyze the nucleotidyltransferase reaction on the covalently immobilized template-primer. An examination of the rate constants for the first and the second nucleotide for the mutant enzymes indicated dissimilar rates, indicating that Gln(190) may be involved in a rate-limiting, conformational change step both before and after the phosphodiester bond formation. Furthermore, the processivity of DNA synthesis by the mutant enzymes was decreased severely, which may result from the lower catalytic efficiency as well as translocation defect.
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669
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Singh K, Vinayak VK, Bhasin DK, Ganguly NK. A monoclonal antibody-based test system for detection of Entamoeba histolytica-specific coproantigen. Indian J Gastroenterol 1999; 18:104-8. [PMID: 10407562] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND Diagnosis of amebiasis based on stool microscopy or demonstration of anti-amebic antibodies has limitations. A diagnostic system based on demonstration of the parasite product in clinical specimens holds promise. METHODS Murine monoclonal antibodies were developed against an Entamoeba histolytica-specific coproantigen. A monoclonal antibody (MoAb) 3D10 was employed in a double-antibody sandwich microELISA system for the detection of amebic coproantigen in fecal specimens. The system was evaluated in three groups of subjects: 63 patients with intestinal amebae, 27 with non-amebic parasitosis, and 57 apparently healthy controls. RESULTS The MoAb 3D10 belonged to IgG1 isotype and recognized three antigens, with mol. wt. 36, 25 and 17 kDa in the crude extract of E. histolytica (HM1-IMSS), and an amebic coproantigen with MW 36 kDa in the stool supernatant from patients with intestinal amebae. The coproantigen was detected in the stool eluates of 56 (89%) patients with intestinal amebae and in none of the stool eluates from other subjects, thereby giving this system a sensitivity of 89% and specificity of 100% for the detection of intestinal amebae. CONCLUSIONS This monoclonal antibody recognizes as intact epitope on the E. histolytica-specific coproantigen. The validity of the MoAb-based microELISA system needs to be established.
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670
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Fong YF, Singh K. Effect of the levonorgestrel-releasing intrauterine system on uterine myomas in a renal transplant patient. Contraception 1999; 60:51-3. [PMID: 10549453 DOI: 10.1016/s0010-7824(99)00061-x] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The levonorgestrel-releasing intrauterine system (LNG-IUS) has been used in the treatment of both idiopathic menorrhagia and adenomyosis. An electronic search of the on-line medical literature revealed no reports of its use for menorrhagia secondary to uterine myomas. Presented here is the successful treatment of uterine myomas with menorrhagia in a woman with a renal transplant. There was a significant reduction in menorrhagia, dysmenorrhea, and uterine and myoma size with the use of the LNG-IUS. We believe that this system provides an alternative to conventional hysterectomy and gonadotrophin-releasing hormonal analog medical treatment for uterine myomas, with a possibly inhibitory effect on myoma growth.
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671
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Sharma BC, Bhasin DK, Sethi A, Vashishta RK, Gupta NM, Singh K. Extended survival of carcinoma head of pancreas following palliative treatment. TROPICAL GASTROENTEROLOGY : OFFICIAL JOURNAL OF THE DIGESTIVE DISEASES FOUNDATION 1999; 20:140-1. [PMID: 10695425] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/14/2023]
Abstract
A 48 year old woman presented with obstructive jaundice 10 years back. Upper gastrointestinal endoscopy revealed a growth infiltrating the ampulla of Vater, which was confirmed to be adenocarcinoma on cytology. At laparotomy, a large nodular growth was seen in the head of pancreas. Surgical resection could not be done because of encasement of superior mesenteric vessels, hence a cholecystojejunostomy was performed. The patient remained asymptomatic for 9 years, when she developed cholangitis. Duodenoscopy at this stage revealed an ulcerated growth at the ampulla and biopsy from the growth confirmed a well differentiated adenocarcinoma. A straight flap 10 F stent was placed in the common bile duct. Thereafter the patient has remained asymptomatic for more than a year.
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672
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Singh K. Depressive disorder in the elderly. Indian J Psychiatry 1999; 41:264. [PMID: 21455402 PMCID: PMC2963004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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673
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Kochhar R, Kumar S, Goel RC, Sriram PV, Goenka MK, Singh K. Pregnancy and its outcome in patients with noncirrhotic portal hypertension. Dig Dis Sci 1999; 44:1356-61. [PMID: 10489918 DOI: 10.1023/a:1026687315590] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
There is paucity of data in the literature on the occurrence of pregnancy and its outcome in patients with noncirrhotic portal hypertension. The present study was undertaken to assess the fertility pattern, fetal loss, and consequences of variceal bleeding during pregnancy in these patients. Fifty-five women of child-bearing age with a diagnosis of noncirrhotic portal hypertension (including 32 with noncirrhotic portal fibrosis and 23 with extrahepatic portal venous obstruction) and 44 age-matched controls were studied. A detailed history of obstetric events and bleeding episodes was recorded in all patients. Any complication of portal hypertension was managed accordingly. Patients were classified into three groups for analysis: group 1-obstetric events after the diagnosis of portal hypertension in patients; group II-obstetric events before the diagnosis of portal hypertension in patients; and group III-obstetric events in controls. A total of 116 pregnancies took place in 44 patients. Of these, 36 occurred after and 80 before the diagnosis of portal hypertension was made. In the 44 controls, 118 pregnancies took place. The mean fertility rates of groups I, II and III were 0.20+/-0.24, 0.18+/-0.21, and 0.22+/-0.12 pregnancies per year, respectively, which were not statistically different (P>0.05). The numbers of fetal losses in groups I, II and III were 3/36 (8.3%), 6/80 (7.5%), and 12/118 (10.17%) pregnancies, respectively. Menstrual irregularities were found in 7/55 (12.72%) patients and 6/44 (13.6%) controls (P>0.05). Five episodes of variceal bleeding occurred in 36 pregnancies after the diagnosis of portal hypertension (13.88%). All five were successfully managed with endoscopic sclerotherapy. In conclusion, noncirrhotic portal hypertensive patients have normal fertility and outcome of pregnancy. Variceal bleeding episodes are not common and endoscopic sclerotherapy is safe and effective in pregnancy.
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Singh K, Fong YF, Prasad RN, Dong F. Does an acidic medium enhance the efficacy of vaginal misoprostol for pre-abortion cervical priming? Hum Reprod 1999; 14:1635-7. [PMID: 10357990 DOI: 10.1093/humrep/14.6.1635] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Absorption pharmacokinetics reveal a relationship between plasma concentrations of misoprostol and its therapeutic effect. To achieve a constant plasma profile and optimal efficacy, it is important to develop a medium that ensures complete dissolution of vaginal misoprostol tablets. Vaginal misoprostol is said to liquefy better in an acidic medium; thus, the aim of this study was to determine whether a 200 microg misoprostol tablet dissolved in acetic acid would be more efficacious than 200 microg misoprostol dissolved in water for pre-abortion cervical priming. A total of 120 healthy nulliparous women requesting legal termination of pregnancy between 6-12 weeks gestation were allocated randomly to either of the study groups. Vacuum aspiration was performed 3-4 h after insertion of the misoprostol tablet. Using Hegar's dilator, the degree of cervical dilatation before operation was measured. Of 60 women, 14 (23%) achieved a cervical dilatation of >/=8 mm when the misoprostol dose was dissolved in acetic acid; 12 (20%) achieved a similar cervical dilatation when the dose was dissolved in water. The mean cervical dilatation for the acid and water media used was 6.3 mm and 6.2 mm respectively; these differences were not statistically significant, neither were pre-operative and intra-operative blood losses statistically different between the two groups. Twenty-four (40%) and four (7%) respectively of women in whom a water medium was used experienced vaginal bleeding and abdominal pain; 20 (33%) and 0 women respectively among those in whom an acetic acid medium was used experienced vaginal bleeding and abdominal pain. These differences in side effects were not statistically significant. Our study shows that the use of acetic acid to dissolve vaginal misoprostol does not improve the efficacy in achieving successful cervical dilatation for pre-abortion cervical priming.
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Bhasin DK, Sharma BC, Sinha SK, Ray P, Vaiphei K, Singh K. Helicobacter pylori eradication: comparison of three treatment regimens in India. J Clin Gastroenterol 1999; 28:348-51. [PMID: 10372934 DOI: 10.1097/00004836-199906000-00013] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/09/2022]
Abstract
Conventional bismuth-based triple therapy has multiple problems, such as inadequate drug compliance, side effects, and drug resistance. Combination of omeprazole and clarithromycin with or without combination with antibiotics like amoxycillin has been shown to be effective in eradication of Helicobacter pylori. Reports from India are few on the efficacy of clarithromycin-based drug combinations. Therefore, we evaluated efficacy of omeprazole and clarithromycin with or without amoxycillin for treating H. pylori infection. Sixty-four consecutive patients with upper gastrointestinal symptoms and having H. pylori infection were included. In every patient, complete upper gastrointestinal endoscopy was done. H. pylori infection was diagnosed by identification of organism on antral biopsies and positive rapid urease test. Patients were treated with omeprazole 40 mg/day + clarithromycin 250 mg twice daily (group I, n = 22), or omeprazole 40 mg/day + clarithromycin 250 mg twice daily + amoxycillin 500 mg three times daily (group II, n = 20), or bismuth subcitrate 120 mg four times daily + amoxycillin 500 mg three times daily + metronidazole 400 mg three times daily (group III, n = 22) for 2 weeks. H. pylori status was reevaluated 1 month after completion of treatment. One patient in each group stopped drugs due to side effects. Eradication rate was not significantly different in group I (15/22, 68%), group II (14/20, 70%), and group III (13/22, 59%). Of those completing therapy, side effects were observed in three patients in group III (nausea, skin rash, metallic taste), whereas none of the patients in group I and group II had any side effects. Addition of amoxycillin did not appear to improve efficacy of dual omeprazole and clarithromycin therapy and appeared to be no different than bismuth, metronidazole, and amoxycillin triple therapy. Overall, none of regimens was particularly good.
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