51
|
Nigam S, Dhingra KK, Gulati A. Ectomesenchymal chondromyxoid tumor of the hard palate - a case report. J Oral Pathol Med 2006; 35:126-8. [PMID: 16430745 DOI: 10.1111/j.1600-0714.2006.00368.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Ectomesenchymal chondromyxoid tumor (ECMT) is a rare tumor. Only 26 cases of ECMT have been reported, all occurred in the anterior tongue. We present a case of a 30-year-old male with a nodule in the hard palate, which was reported as ECMT on histopathology. The differential diagnosis considered included are extraskeletal myxoid chondroma, ECMT, pleomorphic adenoma, oral focal mucinosis, chondroid choristoma, and ossifying fibromyxoid tumor. After serial sections no other component was observed and a diagnosis of ECMT was made by exclusion. The patient is asymptomatic on follow up. A review of existing literature is also presented here.
Collapse
|
52
|
Leeuw NJ, Kock JLF, Pohl CH, Bareetseng AS, Sebolai OM, Joseph M, Strauss CJ, Botes PJ, van Wyk PWJ, Nigam S. Oxylipin covered ascospores of Eremothecium coryli. Antonie van Leeuwenhoek 2005; 89:91-7. [PMID: 16328860 DOI: 10.1007/s10482-005-9012-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2005] [Accepted: 09/06/2005] [Indexed: 11/25/2022]
Abstract
Eremothecium coryli is known to produce intriguing spindle-shaped ascospores with long and thin whip-like appendages. Here, ultra structural studies using scanning electron microscopy, indicate that these appendages serve to coil around themselves and around ascospores causing spore aggregation. Furthermore, using immunofluorescence confocal laser scanning microscopy it was found that hydrophobic 3-hydroxy oxylipins cover the surfaces of these ascospores. Using gas chromatography-mass spectrometry, only the oxylipin 3-hydroxy 9:1 (a monounsaturated fatty acid containing a hydroxyl group on carbon 3) could be identified. Sequential digital imaging suggests that oxylipin-coated spindle-shaped ascospores are released from enclosed asci probably by protruding through an already disintegrating ascus wall.
Collapse
|
53
|
Abstract
Adenomatoid odontogenic tumor (AOT) is an uncommon tumor of odontogenic origin, characterized histologically by the formation of ductlike structures with amyloid-like deposits. Histogenesis of AOT is still uncertain and it is often considered as a hamartomatous lesion rather than a true neoplasm. AOT has a benign behavior and conservative surgical enucleation or curettage is sufficient. We report a case of AOT in a 15-year-old female who presented with left-sided jaw swelling with tooth resorption. Histopathology revealed intraosseus follicular variant of AOT. A brief review of literature is also discussed.
Collapse
|
54
|
Gupta R, Nigam S, Arora P, Khurana N, Batra S, Mandal AK. Clinico-pathological profile of 12 cases of chorangiosis. Arch Gynecol Obstet 2005; 274:50-3. [PMID: 16208478 DOI: 10.1007/s00404-005-0076-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2005] [Accepted: 09/01/2005] [Indexed: 11/24/2022]
Abstract
Chorangiosis is one of the vascular lesions that involves terminal chorionic villi. It is commonly associated with various feto-maternal conditions like pre-eclampsia, diabetes etc. However, the clinical significance of this pathological finding has not been studied extensively. The aim of this study was to identify the various conditions associated with chorangiosis and to determine its clinical significance. A retrospective study to identify the cases of placentas diagnosed with chorangiosis was carried out and the clinical and morphological details of these cases were reviewed. Immunostaining for CD34 and muscle-specific actin was also performed to confirm chorangiosis and to exclude chorangiomatosis. A total of 12 cases of chorangiosis were retrieved, most of them were of term gestation. Five of these 12 cases were associated with various maternal conditions including syphilis (2 cases) and single cases of pre-eclampsia, diabetes and jaundice. One case in each had abruptio placenta and non-immune hydrops. Of these 12 cases, seven were stillborn. Microscopically, all 12 cases showed extensive chorangiosis involving terminal villi. In addition, two cases showed focal infarction and one had extensive calcification. Immunostaining for CD34 confirmed increased number of capillaries while muscle-specific actin was negative, excluding chorangiomatosis. The clinico-pathological profile presented in this study suggests that chorangiosis has characteristic pathological features for its recognition and needs to be differentiated from similar conditions like chorangioma and chorangiomatosis. Also, chorangiosis has potential clinical significance and should be mentioned in the pathology report and the patient should be investigated for associated conditions like syphilis, pre-eclampsia, diabetes etc.
Collapse
|
55
|
Abstract
BACKGROUND Skin involvement in Hodgkin's disease is rare, can be seen in advanced stages of the disease and indicates a poor prognosis. CASE A young male presented with multiple nodular lesions on the chest wall and matted cervical lymph nodes. Aspiration smears from skin lesions showed atypical mononuclear cells with a prominent nucleolus, many lymphocytes and plasma cells. Smears from the lymph nodes showed classical Reed-Sternberg cells in a polymorphous background. The cytologic diagnosis of Hodgkin's lymphoma was entertained and later confirmed on skin biopsy. Past history revealed that the patient had been diagnosed with Hodgkin's disease and treated for it 2 years earlier, but had been lost to follow-up during treatment. CONCLUSION Cutaneous Hodgkin's disease should always be considered in smears from skin lesions showing atypical mononuclear cells in a polymorphous background, even in the absence of a definitive clinical diagnosis at the time of presentation.
Collapse
|
56
|
Sharma P, Chaturvedi KU, Gupta R, Nigam S. Leiomyomatosis peritonealis disseminata with malignant change in a post-menopausal woman. Gynecol Oncol 2005; 95:742-5. [PMID: 15581996 DOI: 10.1016/j.ygyno.2004.09.007] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2004] [Indexed: 12/19/2022]
Abstract
BACKGROUND Leiomyomatosis peritonealis disseminata (LPD) is a rare condition characterized by multiple subperitoneal nodules of benign smooth muscle. The lesion usually occurs in women of childbearing age. CASE A 55-year-old woman with a history of panhysterectomy 8 years ago presented with an abdominal lump. Ultrasonographic and peroperative finding of multiple omental nodules led to a clinical impression of disseminated malignancy. Only the largest nodule was excised, histopathology of which revealed a cellular leiomyoma. Seven months later, she developed an omental leiomyosarcoma. An omentectomy was done and the multiple smaller nodules were all confirmed to be composed of benign leiomyocytes. CONCLUSION Malignant transformation in LPD in post-menopausal patients is an exceptional event that has been documented only twice previously in English literature.
Collapse
|
57
|
Sharma K, Nigam S, Khurana N, Chaturvedi KU. Unilateral gestational macromastia--a rare disorder. THE MALAYSIAN JOURNAL OF PATHOLOGY 2004; 26:125-8. [PMID: 16329566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Macromastia is the massive enlargement of the breast, unilateral or bilateral, disproportionate to the growth of the rest of the body. It is called gravid macromastia or gigantomastia of pregnancy when it occurs during pregnancy. It may or may not regress following parturition. Gestational macromastia is exceptionally rare. We report a 28-year-old female with gigantomastia of the left breast. She presented at four months post-partum with painful massive enlargement of the left breast since the third month of pregnancy. The overlying skin was stretched out and showed multiple ulcers with foul smelling discharge. The nipple and areola were unremarkable. Simple mastectomy was done, as fine needle aspiration cytology was suggestive of phylloides tumour. The breast specimen measured 30 x 30 x 9 cm and was replaced totally by grey-white tissue involving all the resection margins. No normal breast tissue or fat was identified. Histopathology showed periductal as well as diffuse fibrosis, adenosis and lactational changes. No features of phylloides tumour or carcinoma were present and it was diagnosed as unilateral gestational macromastia.
Collapse
|
58
|
Nigam S, Gupta V, Sarda AK. Testicular tumour with features of sex cord tumor with annular tubules associated with cryptorchidism and infertility--a case report. INDIAN J PATHOL MICR 2004; 47:549-51. [PMID: 16295394] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/05/2023] Open
Abstract
Sex cord tumor with annular tubules (SCTAT) is a rare tumor seen in the ovary usually associated with Peutz-Jeghers syndrome. Testicular SCTAT are more infrequent and only four such cases have been reported in the literature. A 28-year-male presented with infertiliy. He had a history of orchiopexy 10 years back for right-sided inguinal testes. A right testicular biopsy done to investigate the cause of infertility revealed testicular atrophy with a focus suspicious of SCTAT. The right-sided orchiectomy revealed two firm nodules of 0.5 and 0.2 cms of SCTAT and sertoli cell nodule (SCN) respectively on microscopy. He did not have any features of Peutz-Jeghers or any other dysgenetic syndrome. He is asymptomatic after follow up of 26 months. This is the fifth case of testicular SCTAT and the first with SCN.
Collapse
|
59
|
Nigam S, Singh T, Singh S. Stromal changes in marrow metastasis. INDIAN J PATHOL MICR 2004; 47:449-50. [PMID: 16295457] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/05/2023] Open
|
60
|
Pahwa R, Gupta SK, Singh T, Nigam S. Acute fulminant visceral leishmaniasis in children--a report of two cases. INDIAN J PATHOL MICR 2004; 47:428-30. [PMID: 16295448] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/05/2023] Open
Abstract
Kala-azar usually presents in older children and young adults with insidious onset of fever, splenomegaly and pancytopenia. Characteristic L.D. bodies in bone marrow or splenic aspirates are diagnostic of kala-azar. We report two cases of visceral leishmaniasis in children-1 1/2 and 10 year old with unusual presentation and fulminant course. In case 1 a female presented with fever, jaundice and bleeding manifestations. Peripheral smear revealed L.D. bodies in neutrophils as well as monocytes. The liver function tests were deranged. The child died within three days due to respiratory arrest. Case 2 was a boy who presented with fever and altered sensorium with deranged liver function tests. The patient expired within three days due to hepatic encephalopathy. Thus, it is important to consider the diagnosis of Kala-azar even when the presenting complaints are atypical and institute diagnostic and therapeutic measures early to prevent mortality.
Collapse
|
61
|
Abstract
OBJECTIVE To delineate the cytomorphologic features of carcinoma ex pleomorphic adenoma (CPA) and identify the diagnostic pitfalls. STUDY DESIGN Smears of 14 cases suspected as CPA on fine needle aspiration over a period of 15 years were reviewed. Cytohistologic correlation was done in 10 cases. RESULTS All cases had a salivary gland mass of 1-16 years' duration, with a rapid increase in size in 10 cases. Epithelial cells predominated over stroma in 11 of 14 cases. Group I showed unequivocal malignant cells admixed with benign epithelial and stromal components of pleomorphic adenoma (PA), which were considered diagnostic of CPA on review. The cytologic differential diagnosis in these cases included mucoepidermoid carcinoma, carcinosarcoma and metastatic adenocarcinoma. Group II comprised 7 cases suspected to be cellular PA with atypia or CPA. These showed mild to moderate degrees of pleomorphism, absence of unequivocal malignant cells, and a variable proportion of benign epithelial and stromal components. Four of them were histologically confirmed as CPA. CONCLUSION Sampling error is an important cause of diagnostic pitfalls. Correlation with clinical data is essential in diagnosis of CPA on cytology. In a proper clinical setting, extensive fine needle aspiration sampling should be done initially. Any degree of nuclear atypia in PA should be documented, alerting the clinician and histopathologist to the possibility of CPA.
Collapse
|
62
|
Nigam S, Singhal N, Kumar Gupta S, Chhabra D, Manaktala U. Placental site trophoblastic tumor in a postmenopausal female—A case report. Gynecol Oncol 2004; 93:550-3. [PMID: 15099979 DOI: 10.1016/j.ygyno.2004.01.045] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2003] [Indexed: 10/26/2022]
Abstract
BACKGROUND Placental site trophoblastic tumor (PSTT) is tumor of intermediate trophoblast, seen commonly in reproductive age group. CASE A 63-year-old postmenopausal woman presented with vaginal discharge, occasional bleeding and a large uterine mass suspicious of malignancy. The uterus ruptured during hysterectomy. A large, necrotic and hemorrhagic tumor was seen in the endometrial cavity infiltrating through the myometrium into serosa. The tumor cells were large pleomorphic, polygonal with variable mitosis. The histological differential diagnosis included choriocarcinoma, epithelioid trophoblastic tumor, epithelioid leiomyosarcoma and poorly differentiated carcinoma. The tumor cells were positive for cytokeratin and beta-hCG and negative for smooth muscle antigen and HMB-45. The final histological diagnosis was PSTT. CONCLUSION PSTT is rare in postmenopausal females. It is difficult to diagnose clinically as well as histologically.
Collapse
|
63
|
Nigam S, Sharma D, Manaktala U, Chaturvedi KU. Lymphangioma of the fallopian tube--a case report. INDIAN J PATHOL MICR 2004; 47:225-6. [PMID: 16295476] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/05/2023] Open
Abstract
Lymphangioma of the fallopian tube is very rare. Only one such case has been reported. A 30-years-old female with lymphangioma of the left fallopian tube is described here. She presented with fever, vaginal bleeding and foul smelling discharge. A mass was felt in left fornix. On exploratory laparotomy, a left tubo-ovarian mass adherent to the surrounding structures was seen. Clinical diagnosis was septic abortion with adhesions. Left-sided partial tubectomy was performed. Histology of the left tube revealed large dilated channels containing lymph in the submucosa. Lymphocytes were also seen in some channels. Histogenesis of lymphangioma remains uncertain. Presence of adhesions in this case suggests a reactive origin. Histopathology is confirmatory for diagnosis.
Collapse
|
64
|
Bareetseng AS, Kock JLF, Pohl CH, Pretorius EE, Strauss CJ, Botes PJ, van Wyk PWJ, Nigam S. Mapping 3-hydroxy oxylipins on ascospores of Eremothecium sinecaudum. Antonie van Leeuwenhoek 2004; 86:363-8. [PMID: 15702389 DOI: 10.1007/s10482-004-0620-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
3-Hydroxy oxylipins were uncovered on ascospores of Eremothecium sinecaudum using immunofluorescence microscopy. This was confirmed by gas chromatography mass spectrometry. These oxylipins were observed only on ascospore parts characterised by nano-scale surface ornamentations simulating a corkscrew as demonstrated by scanning electron microscopy. Conventional ascospore staining further confirms its hydrophobic nature. Using confocal laser scanning microscopy we found that the corkscrew part with spiky tip of needle-shaped ascospores may play a role in rupturing the ascus in order to affect its release. Through oxylipin inhibition studies we hypothesise a possible role for 3-hydroxy oxylipins in facilitating the rupturing process.
Collapse
|
65
|
Singh S, Nigam S, Khurana N, Agarwal SK, Mandal AK. Congenital cystic adenomatoid malformation of lung--report of three cases. INDIAN J PATHOL MICR 2004; 47:29-32. [PMID: 15471120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/30/2023] Open
Abstract
Congenital cystic adenomatoid malformation (CCAM) of the lung is a rare anomaly of fetal development of terminal respiratory structures. We report three cases of congenital cystic adenomatoid malformation (CCAM) of lung Stocker's type I. All the cases presented with progressive neonatal respiratory distress. One case developed hyaline membrane because of ventilator therapy. No other congenital malformation was found in any of our cases. Two of our cases were suspected on antenatal ultrasonography. Routine prenatal ultrasonography has increased the frequency of prenatal diagnosis of congenital cystic lung malformation including CCAM. The pathogenesis, management and prognosis of CCAM are discussed along with a review of literature.
Collapse
|
66
|
Sharma K, Nigam S, Khurana N, Chaturvedi KU. Sclerosing mucoepidermoid carcinoma with eosinophilia of the thyroid--a case report. INDIAN J PATHOL MICR 2003; 46:660-1. [PMID: 15025372] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/29/2023] Open
Abstract
We report a 55-year old female who presented with thyroid swelling for six months. She was clinically asymptomatic with normal thyroid functions. Thyroidectomy revealed the left lobe totally replaced by a well-circumscribed grey white homogenous tumor. Microscopically, the tumor comprised of cells arranged in adenoid pattern along with nests of cohesive intermediate cells, some also forming keratin pearls in a sclerotic and inflammatory background. The thin rim of thyroid at the periphery showed features of lymphocytic thyroiditis. No other associated malignancy was seen on thorough screening. The tumor cells were negative for thyroglobulin and calcitonin. The patient was thus diagnosed with Sclerosing mucoepidermoid carcinoma with eosinophilia, thyroid.
Collapse
|
67
|
Smith DP, Kock JLF, van Wyk PWJ, Pohl CH, van Heerden E, Botes PJ, Nigam S. Oxylipins and ascospore morphology in the ascomycetous yeast genus Dipodascus. Antonie Van Leeuwenhoek 2003; 83:317-25. [PMID: 12777067 DOI: 10.1023/a:1023340900369] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Immunofluorescence microscopy was used to assess members of the yeast genus Dipodascus for the presence of 3-hydroxy oxylipins. Fluorescence was associated with the aggregating ascospores in all species tested, thus suggesting the association of 3-hydroxy oxylipins with these cells, especially the surrounding slime sheaths. An ultrastructural study of the ascospores revealed sheaths with indentations, probably caused by the close packing of the ascospores to form clusters. In addition, an increase in the neutral and glycolipid fractions as well as a decrease in the phospholipid fraction during ascosporogenesis in D. ambrosiae was found.
Collapse
|
68
|
Nanda S, Reddy BSN, Nigam S. Painless sessile swellings on the tongue of a 7-year-old boy. Pediatr Dermatol 2003; 20:361-3. [PMID: 12869164 DOI: 10.1046/j.1525-1470.2003.20420.x] [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: 11/20/2022]
|
69
|
|
70
|
Sarin H, Nigam S, Chaturvedi UK, Tripathi V, Raj A. Malignant nasal paraganglioma: a case report and review of the literature. INDIAN J PATHOL MICR 2003; 46:97-9. [PMID: 15027743] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/29/2023] Open
Abstract
A rare case of malignant nasal paraganglioma is described. A 30 year old female patient presented with a one year history of bilateralnasal obstruction, nasal deformity and recurrent epistaxis. CT scan demonstrated an enhancing mass occupying both nasal cavities, right maxillary antrum and anterior ethmoid sinus. Histopathologic diagnosis was malignant paraganglioma. A total maxillectomy with excision of growth was performed. Post-operative radiotherapy and chemotherapy was given but patient expired before the completion of therapy. Nose being a rare site for paragangliomas, these lesions present a diagnostic challenge to histopathologists and clinicians alike. A review of the four previously described malignant nasal paragangliomas is also presented.
Collapse
|
71
|
Nigam S, Chaturvedi UK. Lingual cysticercosis. INDIAN J PATHOL MICR 2003; 46:148. [PMID: 15027761] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/29/2023] Open
|
72
|
Nigam S, Sarma PV, Ghosh PC, Sarma PU. Characterization of Aspergillus fumigatus protein disulfide isomerase family gene. Gene 2001; 281:143-50. [PMID: 11750136 DOI: 10.1016/s0378-1119(01)00794-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Aspergillus fumigatus is an opportunistic fungus which causes pulmonary complications in humans and animals. The clinical spectrum observed with A. fumigatus is attributed to the multifunctional nature of its antigens. Lack of understanding on the molecular processes and complexity of the fungus have spurred interest in the identification and characterization of its antigens/allergens with biological activities and virulence functions. For identification of some of these antigens/allergens, a cDNA library of A. fumigatus was screened with antibodies of allergic bronchopulmonary aspergillosis (ABPA) patients. One of the reactive clones was sequenced and observed to have an open reading frame of 1095 nucleotides corresponding to a polypeptide of 364 amino acids. The nucleotide and deduced amino acid sequence showed significant homology with the protein disulfide isomerase (PDI) superfamily. The expressed recombinant fusion protein exhibited specific IgG and IgE binding with antibodies present in ABPA patients' sera. The recombinant protein in vitro catalyzed folding of scrambled RNase. The probable epitopic regions of the deduced amino acid sequence were mapped by algorithmic analysis. This is the first report of isolation of a gene encoding a member of the PDI family from A. fumigatus. The PDI superfamily of proteins may play an important role in the protein folding mechanisms of A. fumigatus antigens/allergens for their interaction with the host.
Collapse
|
73
|
Sebolai O, Kock JL, Pohl CH, Smith DP, Botes PJ, Pretorius EE, Van Wyk PW, Nigam S. Bioprospecting for novel hydroxyoxylipins in fungi: presence of 3-hydroxy palmitic acid in Saccharomycopsis malanga. Antonie Van Leeuwenhoek 2001; 80:311-5. [PMID: 11827217 DOI: 10.1023/a:1013089817318] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Electron microscopy studies indicated that the major oxylipin 3-hydroxy palmitic acid (16:0) was associated with aggregating vegetative cells and formed a web-like structure around these cells. Cross sections through this structure showed a hydrophilic outer layer and a more hydrophobic inner layer suggesting that the web-like structure is in fact tube-like micelles. This information sheds more light on the role of these hydroxyoxylipins in fungi.
Collapse
|
74
|
Shankaranarayanan P, Chaitidis P, Kühn H, Nigam S. Acetylation by histone acetyltransferase CREB-binding protein/p300 of STAT6 is required for transcriptional activation of the 15-lipoxygenase-1 gene. J Biol Chem 2001; 276:42753-60. [PMID: 11509556 DOI: 10.1074/jbc.m102626200] [Citation(s) in RCA: 107] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Interleukin-4 (IL-4) induces expression of reticulocyte-type 15-lipoxygenase-1 (15-LOX-1) in various mammalian cells via the Janus kinase/signal transducer and activator of transcription 6 (STAT6) signaling system. We studied the mechanism of 15-LOX-1 induction in A549 lung epithelial cells and found that genistein, a potent tyrosine kinase inhibitor, prevented phopsphorylation of STAT6, its binding to the 15-LOX-1 promoter, and the expression of catalytically active enzyme. In contrast, cycloheximide did not prevent 15-LOX-1 induction. Surprisingly, we found that IL-4 up-regulated the histone acetyltransferase activity of CREB-binding protein (CBP)/p300, which is responsible for acetylation of nuclear histones and STAT6. The acetylation of both proteins appears to be essential for the IL-4-induced signal transduction cascade, because inhibition of CBP/p300 by the viral wild-type E1A oncoprotein abrogated acetylation of both histones and STAT6 and strongly suppressed transcriptional activation of the 15-LOX-1 gene. Moreover, we found that the inhibition by sodium butyrate of histone deacetylases, which apparently suppress 15-LOX-1 gene transcription, synergistically enhanced the IL-4-stimulated 15-LOX-1 expression. These data suggest that both phosphorylation and acetylation of STAT6 as well as acetylation of nuclear histones are involved in transcriptional activation of the 15-LOX-1 gene, although these reactions follow differential kinetics. STAT6 phosphorylation proceeds within the first hour of IL-4 stimulation. In contrast, CBP/p300-mediated acetylation requires 9-11 h, and similar kinetics were observed for the expression of the active enzyme. Thus, our results suggest that in the absence of IL-4, nuclear histones may be bound to regulatory elements of the 15-LOX-1 gene, preventing its transcription. IL-4 stimulation causes rapid phosphorylation of STAT6, but its binding to the promoter appears to be prevented by nonacetylated histones. After 9-11 h, when histones become acetylated, STAT6 binding sites may be demasked so that the phosphorylated and acetylated transcription factor can bind to activate gene transcription.
Collapse
|
75
|
Karihaloo A, Karumanchi SA, Barasch J, Jha V, Nickel CH, Yang J, Grisaru S, Bush KT, Nigam S, Rosenblum ND, Sukhatme VP, Cantley LG. Endostatin regulates branching morphogenesis of renal epithelial cells and ureteric bud. Proc Natl Acad Sci U S A 2001; 98:12509-14. [PMID: 11606725 PMCID: PMC60084 DOI: 10.1073/pnas.221205198] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Endostatin (ES) inhibits endothelial cell migration and has been found to bind to glypicans (Gpcs) on both endothelial cells and renal epithelial cells. We examined the possibility that ES might regulate epithelial cell morphogenesis. The addition of ES to cultured epithelial cells causes an inhibition of both hepatocyte growth factor- and epidermal growth factor-dependent process formation and migration. In contrast, ES does not inhibit epidermal growth factor-dependent morphogenesis in renal epithelial cells derived from Gpc-3 -/mice, whereas expression of Gpc-1 in these cells reconstitutes ES responsiveness. Gpc-3 -/mice have been shown to display enhanced ureteric bud (UB) branching early in development, and cultured UB cells release ES into the media, suggesting that ES binding to Gpcs may regulate UB branching. The addition of ES inhibits branching of the explanted UB, whereas a neutralizing Ab to ES enhances UB outgrowth and branching. Thus, local expression of ES at the tips of the UB may play a role in the regulation of UB arborization.
Collapse
|
76
|
Kock JL, Strauss T, Pohl CH, Smith DP, Botes PJ, Pretorius EE, Tepeny T, Botha A, Nigam S. Bioprospecting for novel oxylipins in fungi: the presence of 3-hydroxy oxylipins in Pilobolus. Antonie Van Leeuwenhoek 2001; 80:93-9. [PMID: 11761371 DOI: 10.1023/a:1012200119681] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
As previously found in various members of the Mucorales, 3-hydroxy oxylipins in Mucor genevensis are associated with the sporangia, i.e. mainly the columella structure and between aggregating sporangiospores. To determine if this phenomenon is also true in distantly related members, the mucoralean fungus Pilobolus was examined. This fungus is characterized by relatively large sub sporangial-columella structures which actively eject sporangia in a sticky liquid for attachment onto herbage surrounding its growth medium--in this case horse dung. Strikingly, this fungus produced a novel oxylipin i.e. a 3-hydroxy monounsaturated fatty acid, possibly a nonenoic acid, which is mainly associated with the sub sporangial-columella structure and aggregating sporangiospores. The specificity of the antibody against 3-hydroxy oxylipins used in immunofluorescence mapping of the mucoralean fungi, was further confirmed in the yeast, Saccharomycopsis malanga which produces 3-hydroxy palmitate in crystal form. These crystals occur between aggregating yeast cells. On the basis of the available data, we hypothesize that 3-hydroxy oxylipins probably function as adhesives, attaching fungal cells to each other or to other surfaces through entropic based hydrophobic forces and/or hydrogen bonds.
Collapse
|
77
|
Deva R, Ciccoli R, Kock L, Nigam S. Involvement of aspirin-sensitive oxylipins in vulvovaginal candidiasis. FEMS Microbiol Lett 2001; 198:37-43. [PMID: 11325551 DOI: 10.1111/j.1574-6968.2001.tb10616.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
3(R)-Hydroxyoxylipins are produced via an aspirin-sensitive pathway in Candida albicans, an abundant pathogen in vulvovaginal candidiasis. In the present study, we have investigated the effect of aspirin on vaginal isolates of C. albicans from patients with recurrent candidiasis. Aspirin alone and with clotrimazole, a commonly used drug, strongly suppressed growth of C. albicans. 3(R)-Hydroxyoxylipins, which were selectively located in hyphae and other filamentous structures, but not in free blastospores, were almost totally suppressed by aspirin. Moreover, C. albicans stimulated prostaglandin E(2) (PGE(2)) production in HeLa cells. PGE(2) is a stimulus for germ tube formation in C. albicans. We conclude therefore that the administration of aspirin should be beneficial in the treatment of vulvovaginal candidiasis by dual ways: (i) by inhibition of 3(R)-hydroxyoxylipin formation, and (ii) by inhibition of PGE(2) formation in the infected host tissue.
Collapse
|
78
|
Nigam S, Rani S, Singh T, Gupta S, Rakheja D, Gaiha M. Clinical, hematological and histomorphological profile of myelodysplastic syndrome. THE JOURNAL OF THE ASSOCIATION OF PHYSICIANS OF INDIA 2001; 49:430-4. [PMID: 11762613] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
AIM The present study was designed to analyse clinical, haematological and histomorphogical features in 37 cases of myelodysplasic syndrome (MDS). MATERIAL AND METHODS FAB criteria was used to diagnose MDS in 37 patients. Clinical details, peripheral blood findings, bone marrow aspirate and biopsy were reviewed. RESULTS Of 37 cases, there were 25 females and 12 males in age range of 2 years to 75 years. There were three children. There were nine cases of refractory anaemia (RA), 18 of refractory anaemia with excess blasts (RAEB), nine of refractory anaemia with excess blasts in transformation (RAEB-t) and one of chronic myelomonocytic leukemia (CMML). All were denovo MDS. All patients had pallor. Hepato and/or splenomegaly was seen in 15 cases. Anemia, leukopenia and thrombocytopenia was seen in 37, 6 and 23 cases respectively. Bone marrow aspiration (BMA) was hyper to normo cellular in 35 cases. Dyshemopoiesis was seen in one or more cell lines in all cases. Bone marrow biopsy (BMB) was available in 16 cases. Abnormal localisation of immature precursors (ALIP) was seen in 11/12 biopsies of RAEB and 3/4 of RAEB-t. BMB was helpful in diagnosis of 3 doubtful cases (one RAEB and two RAEB-t), and upgrading of 2 cases of RAEB to RAEB-t. On follow up, 1 case of RA, 3 of RAEB, 1 of RAEB-t developed AML. One case of RAEB developed ALL and 2 progressed to RAEB-t. CONCLUSION Primary MDS is seen in all age groups. Pallor is commonest presentation. RAEB was commonest subgroup seen. BMB is helpful in diagnosis of doubtful cases. ALIP is a reliable diagnostic feature of MDS. BMB is a diagnostic as well as prognostic tool in MDS cases which should be taken as a mandatory investigation.
Collapse
|
79
|
Goswami D, Sharma K, Zutshi V, Tempe A, Nigam S. Nongestational pure ovarian choriocarcinoma with contralateral teratoma. Gynecol Oncol 2001; 80:262-6. [PMID: 11161870 DOI: 10.1006/gyno.2000.6043] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
BACKGROUND Nongestational pure ovarian choriocarcinoma is a rare malignancy with only 29 cases described to date. CASE We describe a case associated with mature cystic teratoma of the contralateral ovary. Details of all 30 cases including clinical features, associations, surgicopathological findings, operative procedures, postoperative chemotherapy, and outcome are summarized. CONCLUSION This rare malignancy responds well to surgery and postoperative chemotherapy including the methotrexate-based regimes.
Collapse
|
80
|
Nigam S, Stephens M, de Juan A, Rutan SC. Characterization of the polarity of reversed-phase liquid chromatographic stationary phases in the presence of 1-propanol using solvatochromism and multivariate curve resolution. Anal Chem 2001; 73:290-7. [PMID: 11199980 DOI: 10.1021/ac000836k] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
This work characterizes solvation effects in reversed-phase liquid chromatography in the presence of 1-propanol. The solvatochromic method combined with a multivariate curve resolution-alternating least-squares analysis method has been used to characterize two modified silica surfaces--phenyl bonded and C18 bonded silica in mobile-phase mixtures of methanol--water and acetonitrile--water in the presence of 1-propanol. The presence of a small amount of 1-propanol has been shown to affect mainly the polarity properties of the stationary phases while the mobile-phase properties are largely unaffected. The chain collapse mechanism for the C18 stationary phase at higher concentrations of water seems to be inhibited in the presence of 1-propanol, and partitioning is the predominant solute retention mechanism. The phenyl-based phase shows considerably different behavior from that of the C18 phase, and propanol appears to disrupt the pi-stacking interactions between the solute and the phenyl rings anchored to the silica support.
Collapse
|
81
|
Bhatnagar S, Nigam S, Mandal AK. Inflammatory pseudotumour of lung. THE INDIAN JOURNAL OF CHEST DISEASES & ALLIED SCIENCES 2001; 43:55-7. [PMID: 11370509] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/16/2023]
Abstract
Inflammatory pseudotumour of lung is a rare benign lung tumour of uncertain aetiology. It is difficult to distinguish clinically as well as histologically from inflammatory lesions, hamartomas and neoplasms. Only two such cases have been reported from India earlier. We report one such case, that was clinically misdiagnosed as neuroblastoma.
Collapse
|
82
|
Sutherland M, Shankaranarayanan P, Schewe T, Nigam S. Evidence for the presence of phospholipid hydroperoxide glutathione peroxidase in human platelets: implications for its involvement in the regulatory network of the 12-lipoxygenase pathway of arachidonic acid metabolism. Biochem J 2001; 353:91-100. [PMID: 11115402 PMCID: PMC1221546] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
The 12-lipoxygenase pathway of arachidonic acid metabolism in platelets and other cells is bifurcated into a reduction route yielding 12-hydroxyeicosatetraenoic acid (12-HETE) and an isomerization route forming hepoxilins. Here we show for the first time the presence of phospholipid hydroperoxide glutathione peroxidase (PHGPx) protein and its activity in platelets. The ratio of the activity of PHGPx to that of cytosolic glutathione peroxidase (GPx-1) was consistently found to be approx. 1:60 in platelets and UT7 megakaryoblasts. Moreover, short-lived PHGPx mRNA was detected in megakaryocytes but not in platelets. Carboxymethylation of selenium-containing glutathione peroxidases by iodoacetate, which results in the inactivation of PHGPx and GPx-1 without inhibition of 12-lipoxygenase, markedly altered the pattern of arachidonic acid metabolism in human platelets. Whereas the formation of 12-HETE was inhibited by 80%, a concomitant accumulation of 12-hydroperoxyeicosatetraenoic acid (12-HpETE) by two orders of magnitude as well as the formation of hepoxilins A(3) and B(3) were observed. The formation of hepoxilins also occurred when 12-HpETE was added to untreated platelets. In selenium-deficient UT7 cells, which were devoid of GPx-1 but not of PHGPx, the reduction of 12-HPETE was retained, albeit with a lower rate than in control cells containing GPx-1. We therefore believe that both GPx-1 and PHGPx are involved in the regulatory network of the 12-lipoxygenase pathway in platelets and other mammalian cells. Moreover, the diminution of hydroperoxide tone in platelets incubated with arachidonic acid leads primarily to the formation of 12-HETE, whereas the increase in hydroperoxide tone (a situation found under oxidative stress or selenium deficiency or on incubation with 12-HPETE) partly diverts the 12-lipoxygenase pathway from the reduction route to the isomerization route, thus resulting in the formation of hepoxilins.
Collapse
MESH Headings
- 8,11,14-Eicosatrienoic Acid/analogs & derivatives
- 8,11,14-Eicosatrienoic Acid/chemistry
- 8,11,14-Eicosatrienoic Acid/metabolism
- Arachidonate 12-Lipoxygenase/genetics
- Arachidonate 12-Lipoxygenase/metabolism
- Arachidonic Acid/metabolism
- Blood Platelets/cytology
- Blood Platelets/drug effects
- Blood Platelets/enzymology
- Blood Platelets/metabolism
- Blotting, Western
- Cell Line
- Chromatography, High Pressure Liquid
- Cytosol/enzymology
- Erythrocytes/enzymology
- Gas Chromatography-Mass Spectrometry
- Glutathione Peroxidase/genetics
- Glutathione Peroxidase/metabolism
- Humans
- Iodoacetates/pharmacology
- Megakaryocytes/drug effects
- Megakaryocytes/enzymology
- Megakaryocytes/metabolism
- Phospholipid Hydroperoxide Glutathione Peroxidase
- RNA Stability
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Reverse Transcriptase Polymerase Chain Reaction
- Selenium/deficiency
- Selenium/metabolism
Collapse
|
83
|
Abstract
BACKGROUND Cysticercosis cellulosae rarely involves the oral region in humans. METHODS Six cases of oral cysticercosis were diagnosed, three each in lips and buccal mucosa. Diagnosis was made by characteristic gross and histopathologic appearances. RESULTS Of 146 cases of cysticercosis, 6 (4.1%) were of the oral cavity. All 6 cases were initially seen with painless swellings. Clinical differential diagnosis ranged from retention cyst, lipoma, fibroma, neurofibroma, and angular stomatitis. Histopathologic examination revealed cysticercus larvae. CONCLUSIONS The oral cavity is a rare site of involvement by cysticercosis, even in an endemic area. Histopathologic findings of the excised cyst are diagnostic of the lesion.
Collapse
|
84
|
Abstract
Lipid peroxidation of membrane phospholipids can proceed both enzymatically via the mammalian 15-lipoxygenase-1 or the NADPH-cytochrome P-450 reductase system and non-enzymatically. In some cells, such as reticulocytes, this process is biologically programmed, whereas in the majority of biological systems lipid peroxidation is a deleterious process that has to be repaired via a deacylation-reacylation cycle of phospholipid metabolism. Several reports in the literature pinpoint a stimulation by lipid peroxidation of the activity of secretory phospholipase A(2)s (mainly pancreatic and snake venom enzymes) which was originally interpreted as a repair function. However, recent experiments from our laboratory have demonstrated that in mixtures of lipoxygenated and native phospholipids the former are not preferably cleaved by either secretory or cytosolic phospholipase A(2)s. We propose that the platelet activating factor (PAF) acetylhydrolases of type II, which cleave preferentially peroxidised or lipoxygenated phospholipids, are competent for the phospholipid repair, irrespective of their role in PAF metabolism. A corresponding role of Ca(2+)-independent phospholipase A(2), which has been proposed to be involved in phospholipid remodelling in biomembranes, has not been addressed so far. Direct and indirect 15-lipoxygenation of phospholipids in biomembranes modulates cell signalling by several ways. The stimulation of phospholipase A(2)-mediated arachidonic acid release may constitute an alternative route of the arachidonic acid cascade. Thus, 15-lipoxygenase-mediated oxygenation of membrane phospholipids and its interaction with phospholipase A(2)s may play a crucial role in the pathogenesis of diseases, such as bronchial asthma and atherosclerosis.
Collapse
|
85
|
Deva R, Ciccoli R, Schewe T, Kock JL, Nigam S. Arachidonic acid stimulates cell growth and forms a novel oxygenated metabolite in Candida albicans. BIOCHIMICA ET BIOPHYSICA ACTA 2000; 1486:299-311. [PMID: 10903481 DOI: 10.1016/s1388-1981(00)00073-1] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Infection of human tissues by Candida albicans has been reported to cause the release of arachidonic acid (AA), eicosanoids and other proinflammatory mediators from host cells. Therefore, we investigated the interaction of this pathogen with AA. AA stimulated cell growth at micromolar concentrations when used as a sole carbon source. Moreover, it selectively inhibited the antimycin A-resistant alternative oxidase. [1-(14)C]AA was completely metabolised by C. albicans. Only one-seventh of the radioactivity metabolised was found in CO(2), whereas two-thirds occurred in carbohydrates suggesting a predominant role of the glyoxalate shunt of citrate cycle. About 1% of radioactivity was found in polar lipids including eicosanoids. A novel AA metabolite, which revealed immunoreactivity with an antibody against 3(R)-hydroxy-oxylipins, was identified as 3, 18-dihydroxy-5,8,11,14-eicosatetraenoic acid. Using immunofluorescence microscopy, endogenous 3(R)-hydroxy-oxylipins were found in hyphae but not in yeast cells. Such compounds have recently been shown to be connected with the sexual stage of the life cycle of Dipodascopsis uninucleata. Together, we propose that infection-mediated release of AA from host cells may modulate cell growth, morphogenesis and invasiveness of C. albicans by several modes. A better understanding of its role is thus promising for novel approaches towards the treatment of human mycoses.
Collapse
|
86
|
Strauss T, Botha A, Kock JL, Paul I, Smith DP, Linke D, Schewe T, Nigam S. Mapping the distribution of 3-hydroxylipins in the Mucorales using immunofluorescence microscopy. Antonie Van Leeuwenhoek 2000; 78:39-42. [PMID: 11016694 DOI: 10.1023/a:1002757628619] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The distribution of endogenous 3-hydroxylipins (3-OH oxylipins) in representatives of the Mucorales was mapped using immunofluorescence microscopy. Strains of each of the following genera were examined: Absidia, Actinomucor, Cunninghamella, Mortierella (subgenus Micromucor), Mortierella (subgenus Mortierella), Mucor and Rhizomucor. Immunofluorescence microscopy was carried out using an antibody that was raised against 3R-hydroxy-5Z,8Z, 11 Z, 14Z-eicosatetraenoic acid (3R-HETE), which cross-reacts with other 3-OH oxylipins. Subsequently, the occurrence and distribution of the antibody on the various reproductive stages of each fungus was noted. In Absidia, Actinomucor, Mortierella (subgenus Micromucor), Mucor and Rhizomucor, 3-OH oxylipins were found to be associated with the columellae and/or wall of the sporangium. In the representative of Cunninghamella, the 3-OH oxylipins were associated with the single-spored sporangiola. No 3-OH oxylipins were detected in the strains representing Mortierella (subgenus Mortierella).
Collapse
|
87
|
Smith DP, Kock JL, Motaung MI, van Wyk PW, Venter P, Coetzee DJ, Nigam S. Ascospore aggregation and oxylipin distribution in the yeast Dipodascopsis tothii. Antonie Van Leeuwenhoek 2000; 77:389-92. [PMID: 10959568 DOI: 10.1023/a:1002789025872] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Upon cultivation of the yeast Dipodascopsis tothii in its sexual stage, small ascospores are released individually from the ascus tip, which then assemble in sheathed cluster balls. In contrast to Dipodascopsis uninucleata, this yeast produced smooth bean shaped ascospores with sheath-like appendages that assemble in a disordered sheathed ball of ascospores outside the ascus. Strikingly, upon release, the ascus tip contained 3-hydroxy oxylipins, while the released ascospore clusters contained little or no 3-hydroxy oxylipins as indicated by immunofluorescence microscopy. In D. uninucleata, these oxylipins are concentrated on the spore surface and interspore matrix, but not on the ascus tip.
Collapse
|
88
|
Kock JL, Venter P, Smith DP, Van Wyk PW, Botes PJ, Coetzee DJ, Pohl CH, Botha A, Riedel KH, Nigam S. A novel oxylipin-associated 'ghosting' phenomenon in yeast flocculation. Antonie Van Leeuwenhoek 2000; 77:401-6. [PMID: 10959570 DOI: 10.1023/a:1002735216303] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Research on the distribution of oxylipins (3-hydroxy fatty acids) in flocculant strains of the yeast Saccharomyces cerevisiae led to the uncovering of a novel 'ghosting' phenomenon observed during assumed lectin-mediated aggregation. We found that intracellular oxylipin-containing osmiophilic layers migrate through yeast cell walls in a 'ghostlike' fashion without visually affecting the cell wall structure or the layers. This migration resulted in the binding of these layers to cell walls of adjacent cells. Consequently, 'ghosting' seems a prerequisite for flocculation to occur. However, 'ghosting' alone may not be sufficient to ensure flocculation.
Collapse
|
89
|
Nigam S, Schewe T, Kock JL. (3R)-hydroxy-oxylipins--a novel family of oxygenated polyenoic fatty acids of fungal origin. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2000; 469:663-8. [PMID: 10667396 DOI: 10.1007/978-1-4615-4793-8_95] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
|
90
|
Kock JL, Venter P, Botha A, Coetzee DJ, van Wyk PW, Smith DP, Schewe T, Nigam S. Production of 3-hydroxy fatty acids by the yeast Dipodascopsis uninucleata. Biological implications. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2000; 469:675-7. [PMID: 10667398 DOI: 10.1007/978-1-4615-4793-8_97] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
|
91
|
Sutherland M, Schewe T, Nigam S. Biological actions of the free acid of hepoxilin A3 on human neutrophils. Biochem Pharmacol 2000; 59:435-40. [PMID: 10644052 DOI: 10.1016/s0006-2952(99)00345-7] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
In earlier reports and reviews, it was suggested that unlike its methyl ester, the free acid form of the 12-lipoxygenase-derived eicosanoid hepoxilin A3 (HXA3) does not enter neutrophils and other cells. Therefore, in the past, most studies on the biological activities of HXA3 on human neutrophils were conducted with its methyl ester. Here, we present evidence that free HXA3 is biologically active towards human neutrophils at submicromolar concentrations, which may occur under certain circumstances in vivo. Thus, HXA3 caused chemotaxis at concentrations as low as 30-40 nM, an effect which was attenuated at higher concentrations of this eicosanoid. Its chemotactic potency proved to be comparable to that of leukotriene B4, but higher than that of the chemotactic peptide formyl-methionyl-leucyl-phenylalanine (fMLP), and greatly exceeded that of the other 12-lipoxygenase metabolite, 12(S)-hydroxy-5,8,10,14-eicosatetraenoic acid, which was inactive at comparable concentrations. The chemotactic activity of HXA3 was not abolished by serum albumin, but it was suppressed by pertussis toxin. Unlike fMLP, at this concentration range HXA3 did not cause respiratory burst or aggregation of the neutrophils or activation of protein kinase C. These observations suggest a remarkably selective and specific receptor-mediated process. At concentrations higher than 1 microM, HXA3 gives rise to an instantaneous release of calcium from intracellular stores which causes, however, only a slight, if any, liberation of arachidonic acid. On the other hand, pretreatment of the neutrophils with submicromolar concentrations of HXA3 significantly blunts the liberation of arachidonic acid caused by fMLP.
Collapse
|
92
|
Roux-Van Der Merwe M, Kockz J, Nigam S. Ingestion of repeatedly heated edible oil activates phospholipase A2 and protein kinase C in rat liver, kidney and colonic mucosa. Prostaglandins Other Lipid Mediat 1999. [DOI: 10.1016/s0090-6980(99)90425-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|
93
|
Strunck AC, Sutherland M, Schewe T, Nigam S. Studies on the liberation of arachidonic acid and leukotriene B synthesis in fMLP-challenged human neutrophils: Interaction Between cytosolic phospholipase A2 and phospholipase D. Prostaglandins Other Lipid Mediat 1999. [DOI: 10.1016/s0090-6980(99)90426-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
94
|
Nigam S, Kumar G, Sutherland M, Schewe T, Ikawa H, Yamasaki Y, Ueda N, Yamamoto S. Suppression of platelet-type 12-lipoxygenase in uterine cervix of patients with invasive carcinoma. Prostaglandins Other Lipid Mediat 1999. [DOI: 10.1016/s0090-6980(99)90424-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
95
|
Nigam S, Kumar GS, Sutherland M, Schewe T, Ikawa H, Yamasaki Y, Ueda N, Yamamoto S. Metabolic suppression of platelet-type 12-lipoxygenase in human uterine cervix with invasive carcinoma. Int J Cancer 1999; 82:827-31. [PMID: 10446449 DOI: 10.1002/(sici)1097-0215(19990909)82:6<827::aid-ijc10>3.0.co;2-q] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Several types of lipoxygenases with various functions occur in mammalian cells. Although the presence of 12-lipoxygenase activity has been reported in uterine tissues, neither its type nor its biological functions have yet been established. Moreover, the putative role of uterine 12-lipoxygenase in cervical cancer has not been addressed before. Homogenates of uterine tissues from women without cancer and from patients with invasive cervical carcinoma were incubated with (1-(14)C)-arachidonic acid under various conditions and the labelled reaction products were analyzed both by thin-layer chromatography and by high-pressure liquid chromatography. 12-Lipoxygenase protein was estimated by Western blot using anti-serum against recombinant human platelet-type 12-lipoxygenase. Highest concentrations and activities of 12-lipoxygenase were found in the exocervix. The formation of 12S-hydroxy-5Z,8Z,10E, 14Z-eicosatetraenoic acid (12-HETE) was stimulated by micromolar concentrations of 13S-hydroperoxy-9Z,11E-octadecadienoic acid, suggesting metabolic control of the 12-lipoxygenase activity via the hydroperoxide tone. Immunohistochemical investigation revealed that the enzyme is mainly located in the squamous epithelium, and is of platelet-type. Significantly lower values for the 12-HETE formation were found in samples from patients with invasive cervical carcinoma, whereas the amount of immunochemically detectable 12-lipoxygenase protein was unaltered. At the same time the expression levels of the bcl-2 gene were enhanced. Thus, it is concluded that during carcinogenesis the hydroperoxide-reducing capacity of the uterine cervix tissue is enhanced, possibly mediated by bcl-2 protein, and in turn metabolically suppresses the 12-lipoxygenase activity. Furthermore, the data suggest an anti-carcinogenic action of 12-lipoxygenase in human cervix, in contrast to its reported pro-carcinogenic action in breast cancer.
Collapse
|
96
|
Elimian A, Figueroa R, Nigam S, Verma U, Tejani N, Kirshenbaum N. Perinatal outcome of triplet gestation: does prophylactic cerclage make a difference? THE JOURNAL OF MATERNAL-FETAL MEDICINE 1999; 8:119-22. [PMID: 10338066 DOI: 10.1002/(sici)1520-6661(199905/06)8:3<119::aid-mfm9>3.0.co;2-o] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECTIVE To compare the perinatal outcome of triplet gestations with and without prophylactic cerclage. METHODS A retrospective chart review of all triplet gestations delivered between January 1988 and June 1997 was performed. Only women initiating prenatal care before 15 weeks gestation were included. The cerclage group was compared to the no-cerclage group for maternal and perinatal outcome variables. Student t-test, Chi-square, and Fisher's exact test were used for analysis. RESULTS Twenty of the 59 (33.8%) sets of triplet gestations had prophylactic cerclage. There were no differences between groups when compared for maternal age, parity, preterm labor rate, gestational diabetes, anemia, antenatal steroid use, histologic chorioamnionitis, and postoperative endometritis. In addition, there were no differences in mean birth weight, Apgar scores, respiratory distress syndrome (RDS), intraventricular hemorrhage/periventricular leucomalacia (IVH/PVL), and neonatal mortality. Although the mean gestational age at delivery for the cerclage group (32.8+/-2.4 weeks) was not different from the no-cerclage group (31.5+/-3.6 weeks), the proportion of pregnancies delivered at 31 weeks or more, and at 32 weeks or more, was significantly higher in the cerclage group (90 vs. 62%, P = .02; 80 vs. 54%, P = .05), respectively. In addition, the incidence of extremely low birth weight (LBW) was significantly decreased in the cerclage compared with the no-cerclage group (1.7 vs. 15.4%, P = .005). CONCLUSIONS Prophylactic cerclage decreased significantly the incidence of extremely LBW neonates in triplet pregnancies. The proportion of neonates delivered at 31 weeks or more, and at 32 weeks or more was higher in the cerclage group.
Collapse
|
97
|
Kock JL, van Wyk PW, Venter P, Coetzee DJ, Smith DP, Viljoen BC, Nigam S. An acetylsalicylic acid-sensitive aggregation phenomenon in Dipodascopsis uninucleata. Antonie Van Leeuwenhoek 1999; 75:261-6. [PMID: 10427416 DOI: 10.1023/a:1001869410323] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Aggregation of ascospores has been discovered in the yeast Dipodascopsis uninucleata. When this yeast is cultivated to reach the sexual reproductive stage, small ascospores are individually released from the tip of a sac-like ascus which then aggregate in orderly clusters. Acetylsalicylic acid (ASA) inhibited ascospore release and subsequent ordered aggregation process. We suggest that novel ASA-sensitive oxidised fatty acids (3R-hydroxy-oxylipins) and small hooks located on the surface of these ascospores, are involved.
Collapse
|
98
|
O'Rourke DA, Sakurai H, Spokes K, Kjelsberg C, Takahashi M, Nigam S, Cantley L. Expression of c-ret promotes morphogenesis and cell survival in mIMCD-3 cells. THE AMERICAN JOURNAL OF PHYSIOLOGY 1999; 276:F581-8. [PMID: 10198418 DOI: 10.1152/ajprenal.1999.276.4.f581] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
c-Ret, a protein tyrosine kinase receptor, and its ligand glial-derived neurotropic factor (GDNF) are critical for early regulation of ureteric bud development and nephrogenesis. To address whether c-ret directly initiates epithelial cell morphogenesis, the c-ret receptor was expressed in murine inner medullary collecting duct cells (mIMCD-3, a cell line of ureteric bud origin, which has no detectable endogenous c-ret expression). Stable expression of wild-type c-ret was found to yield a constitutively tyrosine-phosphorylated receptor, with no change after the addition of GDNF. Examination of mRNA from these cells demonstrated the message for endogenous GDNF, suggesting that c-ret was potentially being constitutively activated by an autocrine mechanism. When mIMCD-3 cells stably expressing the phosphorylated c-ret receptor were cultured in a type I collagen matrix, they exhibited little GDNF-independent or -dependent branching process formation at early time points compared with the known morphogen hepatocyte growth factor (HGF) (48 h; control, 0.33 +/- 0.33; GDNF, 1.0 +/- 0.58, P = nonsignificant; and HGF, 6.33 +/- 0.33 processes/20 cell clusters, P < 0.001), whereas extended culture (7 days) under serum-free conditions revealed a marked increase in cell survival and the spontaneous development of rudimentary branching process formation. Extended culture (7 days) of c-ret-expressing clones in type I collagen with the epithelial morphogens HGF and/or epidermal growth factor (EGF) resulted in the development of complex three-dimensional spiny cysts, whereas parental mIMCD-3 cells died under these conditions. We conclude that activated c-ret appears to mediate epithelial morphogenesis by prolonging cell survival and, in conjunction with activation of the morphogenic receptors c-met and the EGF receptor, initiates the events required for very early branching morphogenesis.
Collapse
|
99
|
Pace-Asciak CR, Reynaud D, Demin P, Nigam S. The hepoxilins. A review. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1999; 447:123-32. [PMID: 10086189] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
This manuscript reviews the literature on hepoxilins to date. It affords a review of the structures, nomenclature, biosynthesis, catabolism and biological actions of the hepoxilins and some of their chemical analogs. Some unpublished data are also presented. The primary biological action of the hepoxilins appears to relate to their ability to release calcium from intracellular stores through a receptor-mediated action. The receptor is intracellular, and appears to be G-protein coupled. The conversion of hepoxilin into its omega-hydroxy catabolite has recently been demonstrated through the action of an omega-hydroxylase. This enzyme is different from that which oxidizes leukotriene B4, as the former activity is lost when the cell is disrupted, while leukotriene B4-catabolic activity is recovered in both the intact and disrupted cell. Additionally, hepoxilin catabolism is inhibited by CCCP, a mitochondrial uncoupler, while leukotriene catabolism is unaffected. As hepoxilins cause the translocation of calcium from intracellular stores in the endoplasmic reticulum to the mitochondria, it is speculated that hepoxilin omega-oxidation takes place in the mitochondria, and the omega-oxidation product facilitates accumulation of the elevated cytosolic calcium by the mitochondria. The biological activity of stable analogs of the hepoxilins is also described which inhibit the calcium-releasing actions of neutrophil inflammatory mediators.
Collapse
|
100
|
Schewe T, Petrich K, Ludwig P, Kühn H, Nigam S. Effect of 15-HETE on the 5-lipoxygenase pathway in neutrophils. Genuine inhibitor or alternative substrate? ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1999; 447:95-105. [PMID: 10086186 DOI: 10.1007/978-1-4615-4861-4_9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
|