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Pruthi N, Devi BI, Shivshankar JJ, Pandey P. Abscess-a rare fourth ventricular mass. Acta Neurochir (Wien) 2007; 149:1179-81; discussion 1181. [PMID: 17906968 DOI: 10.1007/s00701-007-1238-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2007] [Accepted: 05/22/2007] [Indexed: 10/22/2022]
Abstract
Midline posterior fossa mass lesions in young adults are usually medulloblastomas, pilocytic astrocytomas, haemangioblastomas or ependymomas. We present clinical, imaging and intraoperative findings of an abscess occurring within the fourth ventricle which was associated with right chronic suppurative otitis media and right transverse sinus thrombosis. The possible pathogenesis is discussed.
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77
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Prasad GK, Mahato TH, Singh B, Ganesan K, Pandey P, Sekhar K. Detoxification reactions of sulphur mustard on the surface of zinc oxide nanosized rods. JOURNAL OF HAZARDOUS MATERIALS 2007; 149:460-4. [PMID: 17499919 DOI: 10.1016/j.jhazmat.2007.04.010] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2007] [Revised: 04/02/2007] [Accepted: 04/03/2007] [Indexed: 05/15/2023]
Abstract
Detoxification reactions of sulphur mustard, a deadliest chemical warfare agent were studied on the surface of zinc oxide nanorods at room temperature (32+/-2 degrees C) and the data was compared with that of the bulk ZnO. Prior to the reaction, the nanorods of zinc oxide were synthesized by the hydrothermal method and subsequently characterized by XRD, SEM, TG, N(2) BET, FT-IR. The data revealed the formation of nanorods with diameter ranging from 100 nm to 500 nm with length in microns. Obtained nanomaterial along with bulk ZnO were tested as reactive sorbent for the detoxification of sulphur mustard. Reaction was monitored by GC-FID technique and the reaction products were characterized by GC-MS. Data explores the role of hydrolysis and elimination reactions in the detoxification of sulphur mustard and it also reveals that zinc oxide nanorods and bulk ZnO show the half lives of 8.48 h, 24.75 h in the first 12h and 122.47 h, 177.29 h from 12h to 48 h of the reaction.
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78
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Pandey P, Chaudhary R, Tondon R, Khetan D. Predictable and avoidable human errors in phlebotomy area ? an exclusive analysis from a tertiary health care system blood bank. Transfus Med 2007; 17:375-8. [PMID: 17903139 DOI: 10.1111/j.1365-3148.2007.00793.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Error is a direct reflection of system deficiency. Errors occurring in the phlebotomy area are grossly unreported. Though most of these errors does not lead to catastrophic outcome yet indicate system failure. The aim of the study was to identify errors that took place in phlebotomy area, analysing and classifying them. A prospective audit was conducted during an observational period of 8 months, in an overall cohort of 11 260 donors. The incidence of errors was 3.1%. Fifty-five percent errors were technical and remaining 44.9% were clerical. Of all the technical errors, 57.7% were classified as minor, whereas remaining 42.3% were of major category. Similarly, majority of clerical errors (89.9%) were of minor category. The trained staff accounted for all major events (27.8%). In the minor category, technical errors (73.2%) were more commonly done by trained staff, whereas for clerical errors (58.5%), newly recruited staff was responsible. Errors in phlebotomy area are benign but can compromise donor safety. The study helped to develop a consistent and straightforward classification system for errors and to reduce them by basic interventions. Errors committed mostly by our trained staff indicate the need of regular competency testing and an active system for detection of these deviations.
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79
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Singh KD, Sharma S, Dwivedi A, Pandey P, Thakur RL, Kumar V. Microbial decolorization and bioremediation of melanoidin containing molasses spent wash. JOURNAL OF ENVIRONMENTAL BIOLOGY 2007; 28:675-677. [PMID: 18380094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Molasses spent wash from cane-molasses based distilleries contains a brown coloured recalcitrantpolymer melanoidin, which if disposed untreated poses a great threat to environment. Microbial decolorization and chemical oxygen demand (COD) reduction was found to be dependent on specific carbon and nitrogen source. Under optimal condition of pH, carbon and nitrogen concentration for each treatment, it was found that Bacillus sp isolated from soil was capable of removing COD (85. 35%) and colour (81.10%) from distillery waste to the maximum extent after 9 days atpH 7 in the medium containing 0.5% peptone, 2% glucose and 10% (v/v), followed by Phanerochaete chrysosporium and lowest reduction was obtained by using native microbial consortium.
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80
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Arivazhagan A, Garg N, Devi BI, Dawn BR, Pandey P. Complete ophthalmoplegia associated with clival fracture following trauma: Case report and clinicoanatomical correlation. INDIAN JOURNAL OF NEUROTRAUMA 2007. [DOI: 10.1016/s0973-0508(07)80012-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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81
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Gupta R, Pandey P, Choudhry R, Kashyap R, Mehrotra M, Naseem S, Nityanand S. A prospective comparison of four techniques for diagnosis of paroxysmal nocturnal hemoglobinuria. Int J Lab Hematol 2007; 29:119-26. [PMID: 17474884 DOI: 10.1111/j.1751-553x.2006.00838.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired clonal stem cell disorder with altered expression of glycosylphosphatidylinositol (GPI)-anchored proteins, resulting in the increased susceptibility of erythrocytes to complement-mediated lysis. This study compared the available laboratory methods for detection of PNH cells and evaluated their utility in routine clinical practice. Fifty patients were evaluated by flow cytometric immunophenotyping (FCMI) using CD55 and CD59 monoclonal antibodies, PNH gel card test (GCT), Ham test and sucrose lysis test (SLT). A PNH clone was detectable in erythrocytes in 14 (28%) patients by FCMI, 13 (26%) by GCT and 10 (20%) by Ham test and SLT. The GCT and lytic tests showed 100% specificity and sensitivity was 92.8% and 71.1%, respectively. The GCT results correlated with type III cells (positive for > or =3.21% type III cells) and lytic test results correlated with CD59(-) type III cells (positive for > or =5% CD59(-) type III cells). The GCT and lytic tests were comparable in their sensitivity to detect type II cells (positive for > or =18.5% type II cells). Among the available methods, FCMI is most sensitive, can quantify and delineate PNH cells with differential expression of GPI-anchored proteins. The GCT is a useful screening tool as it is fairly sensitive, easy to perform and interpret. Well-standardized lytic tests are fairly reliable as screening tests.
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82
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Sharma B, Sinha S, Pandey P, Sarkar C, Mehta V. Treatment Strategies for the Treatment of Giant Pituitary Adenomas. Skull Base 2007. [DOI: 10.1055/s-2006-958324] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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83
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Prasad GK, Mahato TH, Singh B, Pandey P, Rao AN, Ganesan K, Vijayraghavan R. Decontamination of sulfur mustard on manganese oxide nanostructures. AIChE J 2007. [DOI: 10.1002/aic.11182] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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84
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85
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Ahmad FU, Pandey P, Sharma BS, Garg A. Foot drop after spinal anesthesia in a patient with a low-lying cord. Int J Obstet Anesth 2006; 15:233-6. [PMID: 16798451 DOI: 10.1016/j.ijoa.2005.11.002] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2005] [Revised: 11/01/2005] [Accepted: 11/01/2005] [Indexed: 11/27/2022]
Abstract
Damage to the spinal cord/conus medullaris due to incorrect identification of the lumbar space is a known complication of lumbar puncture. However, damage to a low-lying cord using an appropriate interspace is extremely rare. We describe a 26-year-old woman who underwent emergency caesarean section under spinal anesthesia. She developed right foot drop immediately after surgery, which gradually recovered over the next 10 months. Magnetic resonance imaging revealed a low lying cord with a fatty filum terminale and intramedullary T2 hyperintensity, suggestive of needle damage.
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86
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Abstract
Pituitary adenomas are uncommon in childhood. This report describes the presentation, endocrinological profile, management and outcome of 42 children with pituitary adenomas. The majority of the tumors were functioning adenomas (40/42, 95.2%). Only two patients (4.8%) had non-functioning tumors. Amongst the functioning tumors, there were 20 patients (47.6%) with prolactinomas, 11 patients (26.2%) with Cushing's disease and nine patients (21.4%) with growth hormone (GH)-secreting adenomas. The most common presenting features were endocrinopathy and visual disturbances. The majority of tumors were macroadenomas, with only eight patients (all with Cushing's disease) having a microadenoma. Transsphenoidal tumor decompression was performed in most cases (71.4%). Complications following transcranial surgery were more frequent when compared to transsphenoidal surgery. There was one death following surgery. Response to radiotherapy was satisfactory. Overall, 67.6% of patients achieved endocrinological remission. Of these, 89% of the children with GH-secreting tumors and 100% of the children with Cushing's disease achieved remission. We conclude that the transsphenoidal approach is effective and safe in surgery for pituitary adenomas in children and is the procedure of choice if there is no contraindication. The combination of surgery and radiotherapy, as well as medical therapy with bromocriptine, achieves good results in the management of these uncommon tumors.
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87
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Rao VK, Sharma MK, Pandey P, Sekhar K. Comparison of different carbon ink based screen-printed electrodes towards amperometric immunosensing. World J Microbiol Biotechnol 2006. [DOI: 10.1007/s11274-006-9154-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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88
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89
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Pandey P, Suri A, Singh AK, Mahapatra AK. Brain abscess--an unusual complication of ventriculo-peritoneal shunt. Indian J Pediatr 2003; 70:833-4. [PMID: 14649482 DOI: 10.1007/bf02723809] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
The authors report a case of a 10-year-old boy, who was operated for a craniopharyngioma with hydrocephalus. He succumbed to delayed development of brain abscess and its consequence, secondary to incompletely treated shunt tract infection. This unfortunate complication developed, despite the fact that conventional steps (removal of VP shunt and intravenous antibiotics) recommended for the treatment of VP shunt infection were adopted. The pathogenesis, management and review of literature of this extremely rare clinical entity is presented.
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90
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Deshwal VK, Pandey P, Kang SC, Maheshwari DK. Rhizobia as a biological control agent against soil borne plant pathogenic fungi. INDIAN JOURNAL OF EXPERIMENTAL BIOLOGY 2003; 41:1160-4. [PMID: 15242282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/30/2023]
Abstract
Rhizobia promote the growth of plants either directly through N2 fixation, supply of nutrients, synthesis of phytohormones and solubilization of minerals, or indirectly as a biocontrol agent by inhibiting the growth of pathogens. The biocontrol effect of rhizobia is due to the secretion of secondary metabolites such as antibiotics and HCN. Siderophore production in iron stress conditions provides rhizobia an added advantage, resulting in exclusion of pathogens due to iron starvation.
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91
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Suri A, Pandey P, Mehta VS. Subarachnoid hemorrhage and intracereebral hematoma following lumboperitoneal shunt for pseudotumor cerebri: a rare complication. Neurol India 2002; 50:508-10. [PMID: 12577109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
Placement of lumboperitoneal (LP) shunt as a surgical treatment for benign intracranial hypertension (BIH) is generally a safe procedure, with complications like mechanical failure, overdrainage and infections. Subarachnoid hemorrhage and intracerebral hematoma were seen after lumboperitoneal shunt in a patient having BIH. These complications were the cause of the patient's deterioration. After removal of the hematoma and performing a decompressive procedure, patient's neurological condition improved. The clinical features, investigations and clinical course are described and the literature reviewed.
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92
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93
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Pandey P. Tetraphenylborate doped polyaniline based novel pH sensor and solid-state urea biosensor. Talanta 2001; 55:773-82. [DOI: 10.1016/s0039-9140(01)00505-7] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2001] [Revised: 07/02/2001] [Accepted: 07/03/2001] [Indexed: 11/30/2022]
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94
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Pandey P, Tripathi M, Chandra PS, Singh VP, Mehta VS. Spontaneous decompression of a posterior fossa arachnoid cyst: a case report. Pediatr Neurosurg 2001; 35:162-3. [PMID: 11641628 DOI: 10.1159/000050413] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The authors present a case of spontaneous regression of a posterior fossa, supracerebellar arachnoid cyst causing hydrocephalus in a 7-month-old male child. The patient presented with macrocrania, bulging fontanelle and upgaze paresis of the eyes. There was complete improvement of these symptoms on the morning of the day of surgery without any obvious precipitating factors, including trauma. CT scan showed complete resolution of the cyst and hydrocephalus. The child was doing well at 1 year of follow-up. To the best of our knowledge, this is the first case report of spontaneous resolution of a posterior fossa arachnoid cyst.
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95
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Ito Y, Pandey P, Mishra N, Kumar S, Narula N, Kharbanda S, Saxena S, Kufe D. Targeting of the c-Abl tyrosine kinase to mitochondria in endoplasmic reticulum stress-induced apoptosis. Mol Cell Biol 2001; 21:6233-42. [PMID: 11509666 PMCID: PMC87342 DOI: 10.1128/mcb.21.18.6233-6242.2001] [Citation(s) in RCA: 109] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The ubiquitously expressed c-Abl tyrosine kinase localizes to the nucleus and cytoplasm. Using confocal microscopy, we demonstrated that c-Abl colocalizes with the endoplasmic reticulum (ER)-associated protein grp78. Expression of c-Abl in the ER was confirmed by immunoelectron microscopy. Subcellular fractionation studies further indicate that over 20% of cellular c-Abl is detectable in the ER. The results also demonstrate that induction of ER stress with calcium ionophore A23187, brefeldin A, or tunicamycin is associated with translocation of ER-associated c-Abl to mitochondria. In concert with targeting of c-Abl to mitochondria, cytochrome c is released in the response to ER stress by a c-Abl-dependent mechanism, and ER stress-induced apoptosis is attenuated in c-Abl-deficient cells. These findings indicate that c-Abl is involved in signaling from the ER to mitochondria and thereby the apoptotic response to ER stress.
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96
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Ito Y, Pandey P, Sathyanarayana P, Ling P, Rana A, Weichselbaum R, Tan TH, Kufe D, Kharbanda S. Interaction of hematopoietic progenitor kinase 1 and c-Abl tyrosine kinase in response to genotoxic stress. J Biol Chem 2001; 276:18130-8. [PMID: 11278340 DOI: 10.1074/jbc.m007294200] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The c-Abl protein tyrosine kinase is activated by certain DNA-damaging agents and regulates induction of the stress-activated protein kinase/c-Jun N-terminal kinase (SAPK/JNK). The hematopoietic progenitor kinase 1 (HPK1) has also been shown to act upstream to the SAPK/JNK signaling pathway. We report here that exposure of hematopoietic Jurkat T cells to genotoxic agents is associated with activation of HPK1. The results demonstrate that exposure of Jurkat cells to DNA-damaging agents is associated with translocation of active c-Abl from nuclei to cytoplasm and binding of c-Abl to HPK1. Our findings also demonstrate that c-Abl phosphorylates HPK1 in cytoplasm and stimulates HPK1 activity. The functional significance of the c-Abl-HPK1 interaction is supported by the demonstration that this complex regulates SAPK/JNK activation. Overexpression of c-Abl(K-R) inhibits HPK1-induced activation of SAPK/JNK. Conversely, the dominant negative mutant of HPK1 blocks c-Abl-mediated induction of SAPK/JNK. These findings indicate that activation of HPK1 and formation of HPK1/c-Abl complexes are functionally important in the stress response of hematopoietic cells to genotoxic agents.
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97
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Ito Y, Pandey P, Sporn MB, Datta R, Kharbanda S, Kufe D. The novel triterpenoid CDDO induces apoptosis and differentiation of human osteosarcoma cells by a caspase-8 dependent mechanism. Mol Pharmacol 2001; 59:1094-9. [PMID: 11306692 DOI: 10.1124/mol.59.5.1094] [Citation(s) in RCA: 106] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The oleanane triterpenoid 2-cyano-3,12-dioxoolean-1,9-dien-28-oic acid (CDDO) is a multifunctional molecule that induces monocytic differentiation of human myeloid leukemia cells and inhibits proliferation of diverse human tumor cell lines. The present studies on human osteosarcoma cells demonstrate that CDDO induces mitochondrial cytochrome c release, caspase-3 activation, and internucleosomal DNA fragmentation. Overexpression of the caspase-8 inhibitor CrmA blocked CDDO-induced cytochrome c release and apoptosis. By contrast, overexpression of the antiapoptotic Bcl-x(L) protein blocked CDDO-induced cytochrome c release, but only partly inhibited caspase-3 activation and apoptosis. In concert with these findings, we demonstrate that CDDO: 1) activates caspase-8 and thereby caspase-3 by a cytochrome c-independent mechanism and 2) induces cytochrome c release by caspase-8-dependent cleavage of Bid. The results also demonstrate that treatment of osteosarcoma cells with CDDO induces differentiation, as assessed by alkaline phosphatase activity and osteocalcin production, and that this response is abrogated in cells that overexpress CrmA. These findings demonstrate that CDDO induces both osteoblastic differentiation and apoptosis by caspase-8-dependent mechanisms.
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98
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Cherian SM, Bobryshev YV, Liang H, Inder SJ, Wang AY, Lord RS, Tran D, Pandey P, Halasz P, Farnsworth AE. Immunohistochemical and ultrastructural evidence that dendritic cells infiltrate stenotic aortocoronary saphenous vein bypass grafts. CARDIOVASCULAR SURGERY (LONDON, ENGLAND) 2001; 9:194-200. [PMID: 11250191 DOI: 10.1016/s0967-2109(00)00102-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
We earlier speculated that antigen-presenting dendritic cells may be involved in the immune reactions leading to saphenous vein bypass graft failure. The purpose of this study was to confirm whether dendritic cells are present in stenotic human saphenous vein bypass grafts. Segments of stenotic saphenous vein grafts were explanted from 14 patients at re-do bypass operation and ten normal saphenous veins were harvested during femoro-popliteal grafting. Sections of specimens were analysed using cell type specific antibodies to identify dendritic cells (CD1a, S-100), T-lymphocytes (CD3), macrophages (CD68), smooth muscle cells (alpha-SMA) and endothelial cells (FVIII). Dual immunostaining, confocal immunofluorescent laser scanning microscopy and electron microscopy were used. Stenotic grafts showed structural alterations of intimal hyperplasia and varying degrees of atherosclerotic degeneration. No cells expressing CD1a and S-100 were observed in the intima and media of normal saphenous veins. Cells expressing these antigens were present around areas of medial neovascularization and within intimal atherosclerotic lesions in saphenous vein bypass grafts. Electron microscopy demonstrated the presence of cells containing a well-developed tubulovesicular system which is unique to cells from the dendritic cell family. Double immunohistochemistry and confocal immunofluorescent microscopy revealed the co-localization of T-lymphocytes with dendritic cells. Dendritic cells are present in stenotic saphenous vein bypass grafts. Dendritic cells may be responsible for antigen presentation and modulation of immune reactions in accelerated graft atherosclerosis through their interaction with T-lymphocytes.
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99
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Cave WK, Pandey P. The limitations of learning from a clinical diagnosis of "probable high-altitude pulmonary edema". Wilderness Environ Med 2001; 11:296-7. [PMID: 11199539] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
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100
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Datta R, Yoshinaga K, Kaneki M, Pandey P, Kufe D. Phorbol ester-induced generation of reactive oxygen species is protein kinase cbeta -dependent and required for SAPK activation. J Biol Chem 2000; 275:41000-3. [PMID: 11042219 DOI: 10.1074/jbc.m009322200] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Treatment of human U-937 myeloid leukemia cells with 12-O-tetradecanoylphorbol-13-acetate (TPA) is associated with protein kinase C (PKC) betaII-mediated activation of the stress-activated protein kinase (SAPK) pathway. The present studies demonstrate that the TPA response of U-937 cells includes the generation of reactive oxygen species (ROS). By contrast, the TPA-resistant U-937 cell variant (TUR), which is deficient in PKCbetaII expression, failed to respond to TPA with the induction of ROS. Moreover, we show that TPA-induced ROS production is restored in TUR cells stably transfected to express PKCbetaII. The results also demonstrate that TPA-induced ROS production is required for activation of the MEK kinase-1 (MEKK-1)--> SAPK pathway. In concert with this observation, treatment of U-937 with H(2)O(2) as a source of ROS is associated with activation of the MEKK-1-->SAPK cascade. These findings indicate that PKCbetaII is required for TPA-induced ROS production and that the MEKK-1-->SAPK pathway is activated by a ROS-mediated mechanism.
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