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Pokharna RK, Garg PK, Gupta SD, Dutta U, Tandon RK. Primary epithelioid haemangioendothelioma of the liver: case report and review of the literature. J Clin Pathol 1997; 50:1029-31. [PMID: 9516888 PMCID: PMC500387 DOI: 10.1136/jcp.50.12.1029] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
A 31 year old female patient presented with a one and a half year history of pain in the upper abdomen. The pain was mild, constant, dull aching, and increased with change in posture or sudden movements. There was no definite relation to meals. She also had a lump in the right upper quadrant, which had been gradually increasing in size over three months. She had mild anorexia and reported a 5 kg weight loss over one year. She had no history of intake of oral contraceptive drugs, exposure to vinyl chloride, thorotrast or any other industrial toxin. Ultrasonography of the abdomen revealed multiple space occupying lesions of altered echotexture in both lobes of the liver. The portal venous system and hepatic vascular system were normal. Computed tomography of the abdomen confirmed the ultrasound findings. Histopathology was diagnostic for primary epithelioid haemangioendothelioma; the first such case reported from India. The patient has been put on a waiting list for a liver transplant.
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Gupta SD, Wu HC, Rick PD. A Salmonella typhimurium genetic locus which confers copper tolerance on copper-sensitive mutants of Escherichia coli. J Bacteriol 1997; 179:4977-84. [PMID: 9260936 PMCID: PMC179352 DOI: 10.1128/jb.179.16.4977-4984.1997] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Three distinct clones from a Salmonella typhimurium genomic library were identified which suppressed the copper-sensitive (Cu(s)) phenotype of cutF mutants of Escherichia coli. One of these clones, pCUTFS2, also increased the copper tolerance of cutA, -C, and -E mutants, as well as that of a lipoprotein diacylglyceryl transferase (lgt) mutant of E. coli. Characterization of pCUTFS2 revealed that the genes responsible for suppression of copper sensitivity (scs) reside on a 4.36-kb DNA fragment located near 25.4 min on the S. typhimurium genome. Sequence analysis of this fragment revealed four open reading frames (ORF120, ORF627, ORF207, and ORF168) that were organized into two operons. One operon consisted of a single gene, scsA (ORF120), whereas the other operon contained the genes scsB (ORF627), scsC (ORF207), and scsD (ORF168). Comparison of the deduced amino acid sequences of the predicted gene products showed that ScsB, ScsC, and ScsD have significant homology to thiol-disulfide interchange proteins (CutA2, DipZ, CycZ, and DsbD) from E. coli and Haemophilus influenzae, to an outer membrane protein (Com1) from Coxiella burnetii, and to thioredoxin and thioredoxin-like proteins, respectively. The two operons were subcloned on compatible plasmids, and complementation analyses indicated that all four proteins are required for the increased copper tolerance of E. coli mutants. In addition, the scs locus also restored lipoprotein modification in lgt mutants of E. coli. Sequence analyses of the S. typhimurium scs genes and adjacent DNAs revealed that the scs locus is flanked by genes with high homology to the cbpA (predicted curved DNA-binding protein) and agp (acid glucose phosphatase) genes of E. coli located at 22.90 min (1,062.07 kb) and 22.95 min (1,064.8 kb) of the E. coli chromosome, respectively. However, examination of the E. coli chromosome revealed that these genes are absent at this locus and no evidence has thus been obtained for the occurrence of the scs locus elsewhere on the genome.
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78
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Gupta SD, Khanna N, Rathi S, Shantharaman R. Extensive keloidal healing of pemphigus vulgaris. Indian J Dermatol Venereol Leprol 1997; 63:199-200. [PMID: 20944325] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Bullae of pemphigus vulgaris heal without scarring. We here report a patient of pemphigus vulgaris whose lesions healed with a one-month history of extensive flaccid bullae and uninfected erosions on the trunk and extremities along with superficial erosions in the oral mucosa. The clinical suspicion of pemphigus vulgaris was confirmed by histopathological and immunohistological examination. Pulse therapy with monthly parenteral dexamethasone and cyclophosphamide pulse was instituted. The cutaneous lesions on healing formed extensive keloidal scars despite high dose of monthly corticosteroid therapy.
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Nunna SV, Sharma R, Goyal M, Berry M, Gupta SD, Deshpande V. Unusual computed tomography appearance of Castleman disease. AUSTRALASIAN RADIOLOGY 1997; 41:193-5. [PMID: 9153824 DOI: 10.1111/j.1440-1673.1997.tb00629.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
A case is presented here of Castleman disease in an uncommon location. Ultrasonography demonstrated a large hypoechoic mass with multiple vascular channels. On computed tomography, the lesions with a nodular contour were located lateral to the carotid sheath on the right side, and demonstrated a variegated enhancement pattern.
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Abstract
The authors report the case of a 6-year-old boy admitted for surgical removal of a 5- x 4-cm neurofibroma over the left wrist. On routine clinical examination a mobile firm, nodular, central abdominal mass was discovered. At laparotomy a tumor (measuring 7 x 5 x 3 cm) arising from the ileal mesentery was found. Complete excision of the mass together with a segment of ileum, followed by end-to-end bowel anastomosis was performed. Histological examination showed that the main elements of the mass consisted of wavy, long-spindled cells that crossed irregularly (pallisading negative). Special stains and immunocytochemistry for S-100 protein confirmed the mass to be a neurofibroma of the mesentery. The patient had an uneventful postoperative course and no signs of recurrence or fresh tumor have been recognized in the 4 years since his operation.
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Mohan A, Sharma SK, Guleria R, Pande JN, Gupta SD. Recurrent hemoptysis in a young male. THE INDIAN JOURNAL OF CHEST DISEASES & ALLIED SCIENCES 1997; 39:47-50. [PMID: 9100409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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82
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Bhattacharya S, Dhillon AP, Winslet MC, Davidson BR, Shukla N, Gupta SD, Al-Mufti R, Hobbs KE. Human liver cancer cells and endothelial cells incorporate iodised oil. Br J Cancer 1996; 73:877-81. [PMID: 8611399 PMCID: PMC2074253 DOI: 10.1038/bjc.1996.156] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Iodised oil (lipiodol) administered via the hepatic artery localises selectively in primary liver cell cancers (hepatocellular carcinomas or HCCs) for prolonged periods and has been used as a vehicle for cytotoxic agents. Despite clinical use, the mechanism of lipiodol retention by tumours has remained unclear, embolisation of oil droplets in the tumour vasculature being the prevailing hypothesis. We have investigated the role of tumour and endothelial cells in lipiodol retention. Human liver tumour (Hep G2) cells and human umbilical vein endothelial cells in culture were exposed to lipiodol. Light microscopy using selective silver impregnation stains and transmission electron microscopy revealed lipiodol incorporation by both cell types, probably by pinocytosis. This was not associated with cellular injury in terms of cell lysis, cell replication or radio-labelled leucine uptake. Histological analysis of 24 HCCs either surgically resected or discovered incidentally at liver transplantation (with prior arterial injection of lipiodol) revealed vesicles of lipiodol in the cytoplasm of tumour cells and endothelial cells lining tumour vessels. Thus, lipiodol is likely to deliver cytotoxic agents directly into tumour cells and endothelial cells, both in vitro and in vivo. This may also apply to other lipids and to other human tumours. These findings have significant therapeutic implications.
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83
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Arora NK, Nanda SK, Gulati S, Ansari IH, Chawla MK, Gupta SD, Panda SK. Acute viral hepatitis types E, A, and B singly and in combination in acute liver failure in children in north India. J Med Virol 1996; 48:215-21. [PMID: 8801280 DOI: 10.1002/(sici)1096-9071(199603)48:3<215::aid-jmv1>3.0.co;2-b] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The aetiological agents responsible for, and the outcome of, acute liver failure were investigated prospectively in 44 children (29 males, 15 females) attending a tertiary health care facility in India. The children were between the ages of 2 months and 13 years. Studies for viral infections and other etiologies could be carried out in 40 patients. Specific aetiological labels were possible in 35 (87.5%) patients. Thirty (75%) had evidence of acute viral hepatitis. Acute hepatitis E virus (HEV) infection was found in a total of 18 children, with hepatitis A (HAV) in 16, hepatitis B in 5, and C in 1. Seven had isolated infection with hepatitis E, five with A, and four with B. Nine had both E and A infection. Superinfection of HEV was observed in a child with Indian childhood cirrhosis (ICC). Acute HEV infection was confirmed by immunoblot assay in all the patients and in eight of these, HEV-RNA was also detected in the serum. HAV was involved in 37.5% of cases with isolated infection in 10% (4 of 40). The aetiological factors associated with acute liver failure, apart from HAV and HEV, were other hepatotropic viruses (22.5%), Wilson's disease (5%), ICC (5%), and hepatotoxic drugs (7.5%). In five patients, no serological evidence of acute viral hepatitis could be found, neither did the metabolic screen yield any result. It was observed that enterically transmitted hepatitis viruses (HAV and HEV) were associated with 60% of acute hepatic failure in children. Mixed infection of HAV and HEV formed the single largest aetiological subgroup. In developing countries, where hepatitis A and E infections are endemic, severe complications can arise in the case of mixed infection. This may contribute to most of the mortality from acute liver failure during childhood.
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Duggal B, Khilnani GC, Ramamurthy S, Misra A, Gupta SD, Pande JN. Unusual presentation of two rare cases of systemic amyloidosis-- a case report. THE JOURNAL OF THE ASSOCIATION OF PHYSICIANS OF INDIA 1996; 44:65-6. [PMID: 8773102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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85
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Babu M, Mathur M, Gupta SD, Chattopadhyay TK. Prognostic significance of argyrophilic nucleolar organizer regions (AGNOR) in oesophageal cancer. TROPICAL GASTROENTEROLOGY : OFFICIAL JOURNAL OF THE DIGESTIVE DISEASES FOUNDATION 1996; 17:57-60. [PMID: 8693588] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
AgNOR (Argyrophilic nucleolar organiser region) has been shown in recent times, to have value in knowing the prognosis of carcinoma oesophagus. We have evaluated the significance of AgNOR in oesophageal cancer with reference to prognosis following treatment. Fifty patients of histologically proven squamous cell carcinoma of the oesophagus were studied. Following oesophagectomy the specimens removed were evaluated for AgNOR number. Of the resected specimens, 25 (50%) had an AgNOR count < or = 3.0, 18 (36%) had an AgNOR count of more than 3 per nucleus and in the remaining 7 cases, AgNOR number was not quantifiable due to the total absence of tumour tissue in the postoperative specimen due to preoperative radiotherapy. When followed up for an average period of 25 months (3 to 47 months), it was seen that patients with AgNOR count of < or = 3.0 per nucleous had a similar mean survival (30.39 +/- 3.29 months) as those with counts > 3.0 per nucleus (27.80 + 3.33 months). The survival in the seven patients in whom no tumour was present following preoperative radiotherapy, was 30.30 +/- 2.42 months. An analysis was done for the presence of change in the AgNOR count before and after radiotherapy in twenty eight case of carcinoma oesophagus treated with preoperative radiotherapy. It was found that the counts on an average were lower in patients after radiotherapy (2.89 +/- 1.04 per nucleus), than before radiotherapy (3.17 +/- 9.69). This was found in 24 cases, while the remaining 4 cases showed no change in count after radiotherapy. This suggested that radiotherapy caused a reduction in AgNOR counts. Mean survival in those with decreased count after radiotherapy was 33.65 (+/- 3.35) months. Since the AgNOR counting is a simple method and can be applied to paraffin embedded section, estimation of the AgNOR number may help in determination of prognosis in patients with oesophageal carcinoma. Preoperative radiotherapy seems to decrease AgNOR count with improved survival. These observations need however, to be reproduced with a larger sample size.
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Dasarathy S, Pandey GK, Bhargava DK, Gupta SS, Gupta SD. Gastrointestinal leiomyomas in a developing country. TROPICAL GASTROENTEROLOGY : OFFICIAL JOURNAL OF THE DIGESTIVE DISEASES FOUNDATION 1995; 16:43-46. [PMID: 8854956] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Twenty one consecutive patients with leiomyoma of the gastrointestinal tract were studied. Recurrent gastrointestinal bleeding was found in 18 (85.7%) and recurrent intestinal obstruction in 3 (14.3%) patients. The commonest site of the lesion was the stomach followed by ileum, jejunum and duodenum. Barium meal examination and gastrointestinal endoscopy were suggestive of the diagnosis in 8 and angiography in 2 patients. The remaining patients were diagnosed peroperatively. All patients underwent excision and remained asymptomatic on follow up except two patients who had a recurrence of the tumor as leiomyosarcoma.
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87
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Ben-Ari Z, Booth JD, Gupta SD, Rolles K, Dhillon AP. Morphometric image analysis and eosinophil counts in human liver allografts. Transpl Int 1995; 8:346-52. [PMID: 7576015 DOI: 10.1007/bf00337165] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Histology of liver allografts is the gold standard for diagnosis of acute cellular rejection. However, scoring the severity of rejection and distinguishing it from other infiltrations is not easy. Only one group has evaluated biopsies morphometrically and also suggested that eosinophils are a specific diagnostic feature. We quantitated eosinophil count in 92 biopsies in a group of 25 patients and, in another group of 30 patients, used morphometric image analysis to measure the cross-sectional area and cell density in each portal tract in day 5 protocol liver biopsies. Rejection was diagnosed by pathological evaluation confirmed with clinical and biochemical graft dysfunction graded histologically into mild or moderate-to-severe. The control groups were five patients with no rejection, nine patients with CMV infection, and eight biopsies in eight patients for whom the cause of the liver dysfunction was obscure. The cross-sectional area, the inflammatory cell count of each portal tract and the mean portal tract inflammatory cell density (cells/mm2) increased with the severity of rejection. In each case the regression coefficient was statistically significant. Correlating the mean of the total inflammatory cell count with the mean of the portal inflammatory cell density (cell/mm2) gave far better separation of the mild rejection and moderate-to-severe rejection groups. Eosinophils were specific for the presence of acute cellular rejection and increased with the severity of rejection. They were absent in the no rejection group, in the CMV group and in those with obscure liver dysfunction. The eosinophil count fell markedly following treatment of rejection.(ABSTRACT TRUNCATED AT 250 WORDS)
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88
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Gupta SD, Lee BT, Camakaris J, Wu HC. Identification of cutC and cutF (nlpE) genes involved in copper tolerance in Escherichia coli. J Bacteriol 1995; 177:4207-15. [PMID: 7635807 PMCID: PMC177164 DOI: 10.1128/jb.177.15.4207-4215.1995] [Citation(s) in RCA: 84] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
It has been suggested previously that copper transport in Escherichia coli is mediated by the products of at least six genes, cutA, cutB, cutC, cutD, cutE, and cutF. A mutation in one or more of these genes results in an increased copper sensitivity (D. Rouch, J. Camakaris, and B. T. O. Lee, p. 469-477, in D. H. Hamer and D. R. Winge, ed., Metal Ion Homeostasis: Molecular Biology and Chemistry, 1989). Copper-sensitive cutC and cutF mutants were transformed with a genomic library of E. coli, and copper-tolerant transformants were selected. Two distinct clones were identified, each of which partially restores copper tolerance in both the cutC and cutF mutants of E. coli. Subcloning, physical mapping, and sequence analysis have revealed that the cutC gene is located at 42.15 min on the E. coli genome and encodes a cytoplasmic protein of 146 amino acids and that the cutF gene is located at 4.77 min on the E. coli genome and is allelic to the nlpE gene independently identified by Silhavy and coworkers (W. B. Snyder, L. J. B. Davis, P. N. Danese, C. L. Cosma, and T. J. Silhavy, J. Bacteriol. 177:4216-4223, 1995). Results from the genetic mapping of the copper-sensitive mutations in the cutF mutant and sequencing of the cutC and cutF (nlpE) alleles from both cutC and cutF mutants indicate that both the cutC and cutF mutants are in fact double mutants altered in these two genes, and mutations in both the genes appear to be required for the copper-sensitive phenotype in each mutant.
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89
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Gupta NP, Singh BP, Raina V, Gupta SD. Primitive neuroectodermal kidney tumor: 2 case reports and review of the literature. J Urol 1995; 153:1890-2. [PMID: 7752342 DOI: 10.1016/s0022-5347(01)67342-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Peripheral neuroectodermal tumors are uncommon cancers arising from outside the central nervous system. The urinary system is rarely involved. The differentiation of these tumors from other small cell cancer and neuroblastoma is based on immunohistochemical differences. We report 2 cases of such tumors arising from the renal parenchyma. Tumor behavior and treatment modalities are discussed.
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90
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Pan J, Gupta SD. Unified description for the nuclear equation of state and fragmentation in heavy-ion collisions. PHYSICAL REVIEW. C, NUCLEAR PHYSICS 1995; 51:1384-1392. [PMID: 9970190 DOI: 10.1103/physrevc.51.1384] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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91
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92
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Kidwai M, Negi N, Gupta SD. Synthesis and antifertility activity of 1,5-diaryl-3-(3'-indolyl)formazans. Chem Pharm Bull (Tokyo) 1994; 42:2363-4. [PMID: 7859335 DOI: 10.1248/cpb.42.2363] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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93
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Kumar P, Flora SJ, Pant SC, Sachan AS, Saxena SP, Gupta SD. Toxicological evaluation of 1-chloroacetophenone and dibenz[b,f]-1,4-oxazepine after repeated inhalation exposure in mice. J Appl Toxicol 1994; 14:411-6. [PMID: 7884145 DOI: 10.1002/jat.2550140605] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Toxicological evaluation was made on the effects of two peripheral sensory irritants (tear gases): 1-chloroacetophenone (CN) and dibenz[b,f]-1,4-oxazepine (CR). Animals had a 15-min daily inhalation exposure to average vapour concentrations of 87.6 mg CN m-3 or 1008 mg CR m-3 (both equal to 0.05 LC50) for 5 or 10 days and were sacrificed 24 h after the last exposure, when biochemical and histopathological observations were made. Both chemicals caused a significant decrease in body weight gain. Histological changes in lung, liver and kidneys were more severe after 10 than after 5 days of exposure and were more severe in CN-exposed than in CR-exposed mice. Organ weight to body weight ratios remained normal except for the spleen to body weight ratio, which decreased in CN-exposed mice after both 5 and 10 days of exposure. Biochemical indicators showed a toxic response only in CN-exposed mice, but the only consistent change was an increase in blood glucose. Hepatic alkaline phosphatase was not influenced, malondialdehyde concentration and acid phosphatase activity were increased only after 5 days of exposure and liver GSH concentration decreased after 10 days of exposure. Results indicate that CN is not only more toxic than CR in absolute terms but is also more toxic at the 5% level of their LC50.
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94
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Rao PV, Bhattacharya R, Gupta SD. Isolation, culture, and toxicity of the cyanobacterium (blue-green alga) Microcystis aeruginosa from a freshwater source in India. BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 1994; 52:878-885. [PMID: 8019082 DOI: 10.1007/bf00200697] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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95
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Agarwal GS, Gupta SD. Filtering of two-photon quantum correlations by optical cavities: Cancellation of dispersive effects. PHYSICAL REVIEW. A, ATOMIC, MOLECULAR, AND OPTICAL PHYSICS 1994; 49:3954-3957. [PMID: 9910692 DOI: 10.1103/physreva.49.3954] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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96
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Gupta SD, Gan K, Schmid MB, Wu HC. Characterization of a temperature-sensitive mutant of Salmonella typhimurium defective in apolipoprotein N-acyltransferase. J Biol Chem 1993; 268:16551-6. [PMID: 8344936] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
On screening 440 temperature-sensitive (ts) mutants of Salmonella typhimurium, a mutant strain SE5312 which accumulated apolipoprotein (ALP) at 42 degrees C was identified. In vitro assay of apolipoprotein N-acyltransferase activity indicated that the mutant cell envelope contained reduced activity as compared to the wild-type strain. Transduction with a Mud-P22 mapping set placed the ts mutation to 14-17 min region of the S. typhimurium chromosome. P22 transduction using transposon insertions in this region revealed a linkage of the ts mutation to cobD (6%), nag (8%), and corC68 (99%). The ts phenotype was complemented by a 2.3-kilobase EcoRI subclone derived from lambda-phage 170 of Kohara's bank of Escherichia coli. Restriction enzyme analysis of the cloned DNA revealed that this 2.3-kilobase EcoRI fragment included the copper transport (cutE) gene in E. coli. The mutant strain SE5312 was copper-sensitive at 30 degrees C, and the complementing clone conferred copper resistance and restored the ALP N-acyltransferase activity in the mutant cell. Wild-type strain of S. typhimurium harboring this clone exhibited elevated levels of ALP N-acyltransferase activity. These results suggest that the cloned gene encodes the ALP N-acyltransferase. Upon shift to the non-permissive temperature, the viability of the mutant cells decreased, and the mutant cells assumed anomalous morphology. Temperature-resistant revertants could be readily isolated, and a subset of tr revertants contained no detectable lipoprotein. A lpp::Tn10 derivative of the mutant SE5312 was also temperature-resistant. These observations suggest that ALP N-acyltransferase is essential for the growth and viability of S. typhimurium, and this requirement is decreased in the absence of major outer membrane lipoprotein.
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97
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Gan K, Gupta SD, Sankaran K, Schmid MB, Wu HC. Isolation and characterization of a temperature-sensitive mutant of Salmonella typhimurium defective in prolipoprotein modification. J Biol Chem 1993; 268:16544-50. [PMID: 8344935] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
A temperature-sensitive (ts) mutant of Salmonella typhimurium that accumulated unmodified murein prolipoprotein at 42 degrees C but not at 30 degrees C was identified. In vivo and in vitro studies of the biosynthesis of Braun's lipoprotein revealed that this mutant (SE5221) was defective in the glyceryl modification of prolipoprotein. The ts mutation was mapped to 60.6 min of the S. typhimurium chromosome and was linked to argA and cysH. A clone with a 1.4-kilobase S. typhimurium DNA insert that complemented the ts mutation and restored the prolipoprotein modification activity both in vivo and in vitro was isolated. DNA sequencing of the complementing region revealed an open reading frame encoding a protein with 291 amino acids lacking NH2-terminal signal sequence. This open reading frame is immediately 5' to the thyA gene and is allelic to umpA of Escherichia coli. Wild-type strains harboring the cloned gene exhibited elevated levels of prolipoprotein modification activity. At the non-permissive temperature, the mutation affected both growth and viability, and the mutant cells exhibited anomalous cell morphology. The ts phenotype was suppressed by the introduction of a lpp::Tn10 mutation. These results suggest that the cloned gene encodes prolipoprotein glyceryl transferase (lgt), and in the wild-type background, this prolipoprotein modification enzyme is essential for the growth and viability of S. typhimurium.
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98
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Mathur M, Gupta SD, Bajpai M, Rohatagi M. Histochemical pattern in alimentary tract duplications of children. Am J Gastroenterol 1991; 86:1419-23. [PMID: 1928031] [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
Detailed histological and histochemical studies using PAS, AB-PAS, and high-iron diamine-AB were done on 12 alimentary tract duplication cysts in children. Nine of these were thoracic and three were abdominal in location. A total of 11 cysts (nine thoracic and two abdominal cysts) were lined by gastric mucosa seen in varying stages of maturation. One triloculated cyst had, in addition, small intestinal mucosa and bronchial wall mucosa. One intra-mucosal rectal cyst was lined exclusively with primitive rectal mucosa. The cysts showed a variable pattern of mucin histochemistry. In three cysts, the gastric mucosa showed neutral mucins. In another three cysts, in addition to neutral mucins, focal positivity for sulphomucins was observed in the apical region of the surface epithelial cells. In the remaining five cysts, the gastric mucosa showed neutral mucins along with a variable mixture of sulpho- and sialomucins. A correlation was seen between mucin histochemistry and the age of the patient. Neutral mucins or focal positivity for sulphomucins was seen in patients aged 7 months or more, whereas a mixture of sulpho-, sialo-, and neutral mucins was identified in patients who were 1 month old, or less.
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99
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Gupta SD, Dowhan W, Wu HC. Phosphatidylethanolamine is not essential for the N-acylation of apolipoprotein in Escherichia coli. J Biol Chem 1991; 266:9983-6. [PMID: 2033085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
It has been postulated that the N-acyl fatty acid attached to the amino terminus of the major Escherichia coli lipoprotein is derived from the fatty acid at the 1-position of phosphatidylethanolamine (PtdEtn) (Jackowski, S., and Rock, C.O. (1986) J. Biol. Chem. 261, 11328-11333). To ascertain the role of PtdEtn in the conversion of apolipoprotein to the mature lipoprotein, the lipoprotein from E. coli strain AH930 (pss::kan) containing a null mutation in the phosphatidylserine synthase gene (pss) was studied. Pulse labeling with [35S]methionine for 30 s or 5 min revealed the formation of mature lipoprotein in both wild-type (W3110) and mutant (AH930) cells. [3H]Palmitate-labeled lipoproteins from both the mutant and wild-type cells were found to contain nearly identical amounts of alkali-resistant (amide-linked, 41-42%) and alkali-labile (ester-linked, 58-59%) fatty acids. Edman degradation and dansylation of the immuno-affinity-purified [35S]cysteine-labeled lipoprotein showed that the NH2 terminus of the lipoprotein in the mutant was blocked as in the wild type. In vitro assay of apolipoprotein N-acyltransferase using membranes either from the mutant or the wild-type strain as the source of both the enzyme and the acyl donor revealed that both membranes were equally active in the conversion of [35S]methionine-labeled apolipoprotein to lipoprotein. These data strongly suggest that PtdEtn is not essential for the N-acylation of apolipoprotein to form lipoprotein, and other major phospholipids such as phosphatidylglycerol and cardiolipin can serve as the donor of fatty acid in the N-acylation of apolipoprotein.
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Gupta SD, Wu HC. Identification and subcellular localization of apolipoprotein N-acyltransferase in Escherichia coli. FEMS Microbiol Lett 1991; 62:37-41. [PMID: 2032623 DOI: 10.1016/0378-1097(91)90251-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Apolipoprotein N-acyltransferase, the enzyme catalyzing the conversion of apolipoprotein to mature lipoprotein, was detected by an in vitro assay using [35S]methionine-labeled apolipoprotein as the substrate. Triton X-100 solubilized the enzyme, and was required for its activity. The enzyme showed a broad pH optimum (pH 6.5-7.5). N-Acylation of apolipoprotein with ethanol-washed membranes was dependent on exogenous phospholipids, with phosphatidylethanolamine, phosphatidylglycerol and cardiolipin all showing about 10- to 20-times enhancement of the enzyme activity in the delipidated membranes. Incubation of apolipoprotein with [3H]palmitate-labeled membranes resulted in the incorporation of [3H]palmitate into lipoprotein. The enzyme was found to be enriched in the inner membrane and in the inner membrane/outer membrane mixed fractions of the E. coli cell envelope.
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