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Mathew R, Raj S, Iype T. P1.212 Primary progressive freezing gait – A clinical study from South India. Parkinsonism Relat Disord 2009. [DOI: 10.1016/s1353-8020(09)70334-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Mathew R, Dhillon V, Shepherd P. Systemic mastocytosis presenting as osteoporosis—a case report. Clin Rheumatol 2009; 28:865-6. [DOI: 10.1007/s10067-009-1165-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2009] [Accepted: 03/09/2009] [Indexed: 10/21/2022]
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Mathew R, Abdullah S, Renfrew I. Massive abdominal wall haematoma and haemothorax due to spontaneous rupture of an intercostal artery. Emerg Med J 2008; 25:608. [DOI: 10.1136/emj.2007.057497] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Barry RJ, Sutcliffe N, Isenberg DA, Price E, Goldblatt F, Adler M, Canavan A, Hamburger J, Richards A, Regan M, Gadsby K, Rigby S, Jones A, Mathew R, Mulherin D, Stevenson A, Nightingale P, Rauz S, Bowman SJ. The Sjögren's Syndrome Damage Index--a damage index for use in clinical trials and observational studies in primary Sjögren's syndrome. Rheumatology (Oxford) 2008; 47:1193-8. [PMID: 18524804 DOI: 10.1093/rheumatology/ken164] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
OBJECTIVE To validate a tool for assessment of accumulated damage in patients with Primary SS (PSS). METHODS Of the total 114 patients fulfilling American-European Consensus Group (AECG) criteria for PSS 104 were included in the study and assessed by rheumatologists at T (time) = 0 months and T = 12 months. On each occasion, damage and activity data, and autoantibody status were collected. SF-36 and Profile of Fatigue and Discomfort-Sicca Symptoms Inventory (PROFAD-SSI) questionnaires were completed. Cross-sectional analysis of this data was subject to a process of expert validation by 11 ophthalmologists, 14 oral medicine specialists and 8 rheumatologists. Items were removed from the index if >or= 50% of respondents recommended exclusion. Statistical validation was performed on remaining items. Spearman's rank analysis was used to investigate associations between damage scores and other disease status measures and Wilcoxon matched-pair analysis to assess sensitivity to change in the damage score. RESULTS Based on the expert validation, a 29-item damage score was agreed incorporating ocular, oral and systemic domains. Total damage score correlated with disease duration at study entry (r = 0.436; P < 0.001), physical function as measured by SF-36 (r = 0.250, T = 0 months; r = 0.261 T = 12 months) and activity as measured by the Sjögren's Systemic Clinical Activity Index (r = 0.213, T = 0 months; r = 0.215, T =12 months). Ocular damage score correlated with the 'eye dry' domain of PROFAD-SSI (r = 0.228, T = 0 months; r = 0.365, T = 12 months). Other associations not present on both assessments were considered clinically insignificant. On Wilcoxon analysis, the index was sensitive to change over 12 months (z = -3.262; P < 0.01). CONCLUSION This study begins validation of a tool for collection of longitudinal damage data in PSS. We recommend further trial in both the experimental and clinical environment.
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Mathew R, Mathuranath PS. Issues in evaluation of cognition in the elderly in developing countries. Ann Indian Acad Neurol 2008; 11:82-8. [PMID: 19893644 PMCID: PMC2771956 DOI: 10.4103/0972-2327.41874] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Revised: 06/03/2008] [Accepted: 06/03/2008] [Indexed: 11/11/2022] Open
Abstract
BACKGROUND Developing regions of the world host the majority of elderly subjects who are at risk for dementia. Reliable epidemiological data from these countries is invaluable in tackling this global problem. Scarcity of such data in literature is largely attributable to problems that are unique to developing communities worldwide. OBJECTIVE To classify and describe the problems that interfere with the collection of reliable epidemiological data on cognitive impairment in the elderly in developing communities, and to suggest practical solutions for some of them. METHODS Inferring from the experiences of a large, ongoing, population-based study on the cognitive impairments in the elderly in South India and from the review of literature. CONCLUSION A fatalistic attitude regarding aging in the communities, significant heterogeneity in educational abilities and activities of daily living, high illiteracy among rural subjects, and lack of an organized health care system and updated demographic figures are some of the major factors that contribute to technical, namely, methodology-related problems and practical, namely, subject-related problems in such epidemiological studies.
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Mardikar M, Deo D, Deshpande NV, Khanolkar U, Mathew R, Khan A, Bhagwat A, Sahoo P, Prasad N, Mardikar HM. Indo Heart Survey on latent abnormal glucose regulation in patients with coronary artery disease without diabetes across India. Indian Heart J 2008; 60:113-118. [PMID: 19218719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023] Open
Abstract
BACKGROUND The Euro Heart Survey on diabetes and heart has demonstrated high prevalence of latent glucose abnormalities in non-diabetic patients with coronary artery disease (CAD) in the European population. The aim of our survey was to assess the prevalence of latent abnormal glucose regulation in adult non-diabetic CAD patients in India. METHODS AND RESULTS Seven centers distributed across India recruited 350 patients. The diagnosis of CAD was done by coronary angiography showing >50% stenosis in any major epicardial coronary artery or its branches. Oral glucose tolerance test (OGTT) and fasting glucose levels were used to characterize glucose metabolism. Venous plasma glucose was measured before (fasting) and 2 hours after ingestion of glucose. Impaired fasting glucose (IFG) was defined as OGTT (0 minute)>or=100 mg/dl but <126 mg/dl and OGTT (2 hours)<140 mg/dl. Impaired glucose tolerance (IGT) was defined as OGTT (0 minute)<126 mg/dl and OGTT (2 hours)>or=140 mg/dl but <200 mg/dl. Of the 350 patients studied, 176 (50.28%) had impaired glucose regulation (IFG-28 [8%]; IGT-148[42.28%]) and 75 (21.42%) had newly detected Diabetes. In all 251 (71.7%) patients with CAD had previously undetected abnormal glucose regulation. CONCLUSION This survey demonstrates the presence of abnormal glucose regulation in almost three quarters of the non-diabetic Indian CAD patients. OGTT should be recommended as routine screening test for detecting latent glucose abnormalities in all CAD patients.
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Bowman SJ, Sutcliffe N, Isenberg DA, Goldblatt F, Adler M, Price E, Canavan A, Hamburger J, Richards A, Rauz S, Regan M, Gadsby K, Rigby S, Jones A, Mathew R, Mulherin D, Stevenson A, Nightingale P. Sjogren's Systemic Clinical Activity Index (SCAI) a systemic disease activity measure for use in clinical trials in primary Sjogren's syndrome. Rheumatology (Oxford) 2007; 46:1845-51. [DOI: 10.1093/rheumatology/kem280] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Srinivasan S, Sheela D, Mathew R, Bazroy J, Kanungo R. Risk factors and associated problems in the management of infections with methicillin resistant Staphylococcus aureus. Indian J Med Microbiol 2006; 24:182-5. [PMID: 16912437] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
PURPOSE It is necessary to define the problem of methicillin resistant Staphylococcus aureus (MRSA) in every hospital to evolve control strategies. The objectives of this study were to determine factors influencing the persistence of MRSA in patients with hospital acquired infection and to identify alternate cost effective antibiotics. METHODS A six month study was carried out for 50 patients with MRSA infection. Treatment modalities and risk factors were determined by a preset protocol. Minimum inhibitory concentration of commonly used antibiotics was determined. RESULTS The risk factors were prolonged postoperative morbidity, prior antibiotic therapy and emergency admissions. Seventy percent of the isolates were from postoperative cases undergoing emergency surgeries. Isolation was highest during the second week of hospital stay. Emergency admissions had a significantly higher chance of early isolation. Prior treatment with multiple antibiotics in 38% was found to be another major risk factor. Ofloxacin was seen to be efficacious in a small percentage of cases. Rifampicin in combination with ofloxacin and clindamycin were found to be other good alternatives. Ofloxacin was found to be the cheapest and vancomycin the most expensive, for a full course of treatment. CONCLUSIONS Minimizing risk factors and attention to alternate cost effective combination therapy may ease the problem of management of infections with MRSA.
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Mathew R, Rajalakshmi A, Grillet D, Krishnan VS, Madhusudhananan S. Acute axonal polyneuropathy in an unventilated patient with sepsis. THE JOURNAL OF THE ASSOCIATION OF PHYSICIANS OF INDIA 2006; 54:235-7. [PMID: 16800351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Critical Illness Polyneuropathy (CIP) represents an acute axonal neuropathy that develops during treatment of severely ill patients and remits spontaneously once the critical condition is under control. Except for differences in the predisposing causes, it is difficult to distinguish CIP from axonal Guillain-Barré Syndrome (GBS) on purely clinical grounds. We describe a 70 years lady who developed acute axonal polyneuropathy two weeks following snakebite. She developed this in the background of sepsis but never required ventilatory support. The difficulties in differentiating CIP from axonal GBS are discussed. The hypothesized overlap between both these syndromes is also reviewed.
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Mathuranath PS, George A, Mathew R, Cherian PJ. Profiles of language impairment in progressive nonfluent aphasia. Ann Indian Acad Neurol 2006. [DOI: 10.4103/0972-2327.22818] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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Mathuranath PS, George A, Mathew R, Cherian PJ. Authors′ reply. Ann Indian Acad Neurol 2006. [DOI: 10.4103/0972-2327.25990] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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Kanungo R, Srinivasan S, Mathew R, Kannan M. Unusual morphological forms of Cryptococcus neoformans in cerebrospinal fluid. Indian J Med Microbiol 2004; 22:188-90. [PMID: 17642731] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Cryptococcal meningitis is recognized as one of the AIDS defining conditions. It acts as a diagnostic marker for further investigations to establish the retroviral infection. Cryptococcus neoformans can be readily identified by its characteristic capsulated morphology. But rarely variations in morphology may be seen. We report a case of chronic meningitis in an AIDS patient whose cerebrospinal fluid (CSF) stained with India ink showed elliptical, peanut shaped and pseudomycelial large yeast cells with thick capsules. The organism was cultured and identified as Cryptococcus neoformans var neoformans. Unusual morphological forms may create diagnostic dilemma in the rapid diagnosis of cryptococcal meningitis.
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Shashikala, Kanungo R, Srinivasan S, Mathew R, Kannan M. UNUSUAL MORPHOLOGICAL FORMS OF CRYPTOCOCCUS NEOFORMANS IN CEREBROSPINAL FLUID. Indian J Med Microbiol 2004. [DOI: 10.1016/s0255-0857(21)02835-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Mathew R, Raj RS, Sudha P. Late postpartum eclampsia without prodroma. Neurol India 2003; 51:539-40. [PMID: 14742943] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/28/2023]
Abstract
Late postpartum eclampsia is an increasingly recognized entity. We describe a patient who developed postpartum eclampsia on the 6th day of delivery without any preceding pre-eclampsia. A high index of suspicion and close follow-up will help in the early detection of this condition. Awareness of this condition will also save the patient from unnecessary investigations. This may be all the more relevant in developing countries where eclampsia contributes to one-third of maternal mortality and the resources for patient investigation and management are limited.
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Sudha G, Nirupa C, Rajasakthivel M, Sivasusbramanian S, Sundaram V, Bhatt S, Subramaniam K, Thiruvalluvan E, Mathew R, Renu G, Santha T. Factors influencing the care-seeking behaviour of chest symptomatics: a community-based study involving rural and urban population in Tamil Nadu, South India. Trop Med Int Health 2003; 8:336-41. [PMID: 12667153 DOI: 10.1046/j.1365-3156.2003.01010.x] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Our aim was to identify the factors that influence the care-seeking behaviour of chest symptomatics in urban and rural areas in South India. We conducted in-depth interviews with 649 participants: 80% of 310 urban residents and 63% of 339 rural people had sought care (P < 0.01), 93% within 1 month of onset of symptoms. Private health care facilities were the first and preferred point of contact for 57% of urban and 48% of rural participants; the major reasons were proximity to residence and their perception that good-quality care would be available there. Symptomatics who did not seek care attributed their inaction to insufficient severity of symptoms (51%), unaffordability (46%) and lack of time due to work pressures (25%). Socio-economic factors such as literacy and family income significantly influenced care-seeking behaviour. Our results indicate that most chest symptomatics seek care promptly; their initial response is to go to the nearest private health care facility, shifting to another if they are dissatisfied. Fifty per cent of the participants who did not seek care felt that their symptoms were not severe.
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Chaudhuri KR, Pal S, DiMarco A, Whately-Smith C, Bridgman K, Mathew R, Pezzela FR, Forbes A, Högl B, Trenkwalder C. The Parkinson's disease sleep scale: a new instrument for assessing sleep and nocturnal disability in Parkinson's disease. J Neurol Neurosurg Psychiatry 2002; 73:629-35. [PMID: 12438461 PMCID: PMC1757333 DOI: 10.1136/jnnp.73.6.629] [Citation(s) in RCA: 445] [Impact Index Per Article: 20.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BACKGROUND No formal instruments are available for quantifying sleep problems in Parkinson's disease. OBJECTIVE To develop a new sleep scale to quantify the various aspects of nocturnal sleep problems in Parkinson's disease, which may occur in up to 96% of affected individuals. METHODS Employing a multidisciplinary team approach, a visual analogue scale was devised addressing 15 commonly reported symptoms associated with sleep disturbance in Parkinson's disease-the Parkinson's disease sleep scale (PDSS). In all, 143 patients with Parkinson's disease completed the PDSS, covering the entire spectrum of disease from newly diagnosed to advanced stage. As controls, 137 age healthy matched subjects also completed the scale. Test-retest reliability was assessed in a subgroup of subjects. The Epworth sleepiness scale was also satisfactorily completed by 103 of the patients with Parkinson's disease. RESULTS PDSS scores in the Parkinson group were significantly different from the healthy controls. Patients with advanced Parkinson's disease had impaired scores compared with early/moderate disease. Individual items of the scale showed good discriminatory power between Parkinson's disease and healthy controls. Relevant items of the PDSS correlated with excessive daytime sleepiness. The scale showed robust test-retest reliability. CONCLUSIONS This appears to be the first description of a simple bedside screening instrument for evaluation of sleep disturbances in Parkinson's disease. A combination of subitems may help identify specific aspects of sleep disturbance, which in turn may help target treatment.
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Ahmed B, al-Howiriny TA, Mathew R. Antihepatotoxic activity of Phyllanthus fraternus. DIE PHARMAZIE 2002; 57:855-6. [PMID: 12561252] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
Different fractions of alcoholic extracts of aerial parts and roots of Phyllanthus fraternus Webster (Euphorbiaceae) were screened for antihepatotoxic activity on carbon tetrachloride induced liver damage in albino rats. The degree of protection was measured using biochemical parameters like serum glutamic oxaloacetic transaminase (SGOT), serum glutamic pyruvate transaminase (SGPT), total protein (TP) and total albumin (TA). The methanol fraction was found to be the most active, which was further supported by a significant recovery of hepatocytes in the histopathological study of the liver showing almost complete normalization of the tissues as neither the fatty accumulation nor the necrosis was observed.
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Nirmala R, Mathew R, Narayanan PR. Reduced cytokine secretions by LAK cells of pulmonary tuberculosis patients in response to tumor targets in vitro. J Interferon Cytokine Res 2002; 22:617-20. [PMID: 12162871 DOI: 10.1089/10799900260100097] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Activation of macrophages and other immune components to release a series of proinflammatory cytokines is one of the first events in innate resistance to intracellular infections. Severe manifestations of tuberculosis (TB) could be caused by alterations in the balance of these cytokines. In this study, lymphokine-activated killer (LAK) cells of TB patients and normal individuals were generated by stimulation with cytokines in vitro. The LAK cells of both groups were further triggered with allogeneic tumor targets. Cytokines interferon-gamma (IFN-gamma), tumor necrosis factor-alpha (TNF-alpha), and granulocyte-macrophage colony-stimulating factor (GM-CSF) were estimated in the supernatants generated in the two groups. The aim was to see if infection with TB influenced the secretory capacity of the immune cells in vitro. Reduced cytokine profiles were observed in TB patients, indicating defective interactions between patient effector cells with allogeneic transformed cells compared with normal individuals. Partial restoration of IFN-gamma production was seen with a combination of cytokines interleukin-2 (IL-2) and IL-12 in TB patients. Based on the in vitro observations, we hypothesize that in vivo also there is diminished immune cell activation of effector cells in response to the presence of infected macrophages. This probably leads to a diminished secretory function that can be corrected by the use of such cytokines as IL-2 and IL-12. The effector populations of TB patients are probably in a state of target-induced anergy, allowing the bacteria to thrive, and immunomodulatory cytokines that improve the host immune response toward countering mycobacterial infection.
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Mathew R, Arora S, Khanna R, Mathur M, Shukla NK, Ralhan R. Alterations in p53 and pRb pathways and their prognostic significance in oesophageal cancer. Eur J Cancer 2002; 38:832-41. [PMID: 11937319 DOI: 10.1016/s0959-8049(02)00007-2] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The pRb (p16-pRb-cyclin D1) and p53 (p53-MDM2-p21) pathways play a critical role in tumorigenesis. To evaluate which of these cell cycle regulatory proteins are related to patients' prognosis, a comprehensive analysis of alterations in these components was carried out in 100 ESCCs (oesophageal squamous cell carcinoma) using immunohistochemistry and correlated with clinicopathological parameters by univariate analysis. Overexpression of p53, MDM2 and cyclin D1 proteins was observed in 73, 42 and 67% of the cases, respectively, while loss of expression of p21, p16 and pRb was observed in 36, 45 and 75% of the cases, respectively. Multiple logistic regression analysis revealed that loss of p16 immunoreactivity was a significant risk factor for tumour stage (pT) (Odds Ratio (OR)=3.3), whereas the loss of pRb was a significant risk factor for nodal metastasis (pN) (OR=8.8). MDM2 overexpression emerged as the most significant risk factor for distant organ metastasis (pM) (OR=4.6). Of the ESCC patients who underwent oesophagectomy, 50 cases were followed-up for a maximum period of 44 months and median of 16 months. Survival analysis revealed that Cyclin D1 overexpression is an adverse prognosticator for disease-free survival, as well as overall survival, and tumour stage (pT) is an adverse prognosticator for disease-free survival. In conclusion, these data support a model of oesophageal cancer pathogenesis in which both the pRb and p53 pathways are inactivated and suggests an in-depth evaluation of the clinical utility of these putative markers is warranted.
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Nirmala R, Narayanan PR, Mathew R, Maran M, Deivanayagam CN. Reduced NK activity in pulmonary tuberculosis patients with/without HIV infection: identifying the defective stage and studying the effect of interleukins on NK activity. Tuberculosis (Edinb) 2002; 81:343-52. [PMID: 11800585 DOI: 10.1054/tube.2001.0309] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
SETTING A study was undertaken to understand the non-major histocompatibility restricted cytotoxicity in order to delineate the role of natural killer (NK) cells towards the development of host immunity to tuberculosis. OBJECTIVE (a) Enumeration of NK cell numbers and activity in normal individuals (35), pulmonary tuberculosis patients (32), HIV-infected TB patients (20) and patient contacts (10), (b) effect of treatment on NK status, (c) enumeration of effector-target conjugates and (d) effect of in vitro cytokine stimulation on NK activity. DESIGN NK cells were enumerated by flow cytometry. NK activity was assessed by chromium release assay before and after treatment for tuberculosis and after stimulation with IL-2/IL-12. Novel flow cytometric method was standardized to enumerate effector-target conjugates. RESULTS No changes were seen between different groups as far as number of NK cells and relative proportions of different conjugate types were concerned, but there was a decrease in NK activity in TB patients which increased after treatment. Augmentation of NK activity was observed after cytokine stimulation. CONCLUSION Lowered NK activity during tuberculosis infection is probably the 'effect' and not the 'cause' for the disease as demonstrated by the follow-up study. Similar number of conjugates in both groups indicates no defect in the recognition/binding step but probably at subsequent steps of the cytotoxic process. Augmentation of NK activity with cytokines implicates them as potential adjuncts to tuberculosis chemotherapy.
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Chalmers JM, Hodge C, Fuss JM, Spencer AJ, Carter KD, Mathew R. Opinions of dentists and directors of nursing concerning dental care provision for Adelaide nursing homes. Aust Dent J 2001; 46:277-83. [PMID: 11838875 DOI: 10.1111/j.1834-7819.2001.tb00292.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND The complex oral health problems of nursing home residents have been well documented. However, the influences on residents' oral health status, including opinions and experiences of dental professionals and nursing home staff, have not yet been adequately investigated. METHODS The baseline questionnaire component of this longitudinal study was mailed to all registered dentists practising in Adelaide and Adelaide nursing home directors of nursing (DONs). RESULTS 413 dentists and 97 DONs indicated that Adelaide dentists' interest and training in nursing home dentistry was low. Dental service provision for nursing home residents was very low and dentists preferred to provide treatment at their dental practices. Few dental hygienists were working in nursing homes and dental professionals provided little educational assistance for nursing home staff. Dentists and DONs held several common and many varying perceptions of the problems associated with dental care provision in nursing homes. Both identified a group of nursing home environmental constraints and a lack of portable dental equipment. DONs further identified a group of resident related problems, and dentists a group of dental practice-related problems. CONCLUSIONS These study results provide important information concerning problems with nursing home dentistry for dental service providers, educators, policy-makers, administrators and nursing home staff.
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Kindo AJ, Mathew R, Ravi A, Varadrajan M. Rare co-existence of Salmonella typhi and mycobacteria tuberculosis in a psoas abscess--a case report. INDIAN J PATHOL MICR 2001; 44:493-4. [PMID: 12035378] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2023] Open
Abstract
We report a rare case of dual infection in a psoas abscess. Pus from the abscess grew Salmonella typhi and the abscess wall showed epitheloid granulomas giant cells, which we confirmed as tuberculosis by PCR. Such dual infection cases may be missed unless looked for since both these infections are common in our country.
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Mathew R, Arora S, Mathur M, Chattopadhyay TK, Ralhan R. Esophageal squamous cell carcinomas with DNA replication errors (RER+) are associated with p16/pRb loss and wild-type p53. J Cancer Res Clin Oncol 2001; 127:603-12. [PMID: 11599796 DOI: 10.1007/s004320100249] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
PURPOSE Microsatellite instability (MSI) as a determinant of propensity to esophageal squamous cell carcinoma (ESCC) at seven microsatellite markers at 2p (2p15-16), 3p (3p13, 3p14.1-3, 3p25, and 3p26) and 16q (16q12.1-3) was investigated to analyze their putative role as indicators of predisposition to esophageal malignancies. METHODS Seven microsatellite loci were amplified by polymerase chain reaction, from surgically resected tumor tissues from 30 ESCC patients from Indian population, to assess the loss of heterozygosity (LOH) and replication error repeats (RER) and to correlate these alterations with aberrations in major cell cycle regulatory proteins and histopathological parameters. RESULTS LOH and RER analyses at these loci demonstrated moderate microsatellite alterations, suggesting the involvement of MSI in esophageal tumorigenesis in a subset of the Indian population. MSI, defined as RER in at least two or more of the loci studied, was observed in ten of 30 (33%) patients. Twenty-two of 30 patients (73%) showed LOH at one or more loci, while 17 of the 30 patients (60%) showed RER in at least one of the loci studied. RER-positive patients showed a trend towards better prognosis when compared to RER-negative patients. MSI demonstrated a significant association with concomitant loss of p16 and pRb (p16-/pRb- phenotype) (P=0.046). Interestingly, we observed an inverse correlation between MSI and p53 mutations (P=0.03) suggesting that MSI may provide a p53-independent pathway for esophageal tumorigenesis in RER+ patients. MSI showed a trend towards longer survival and absence of distant organ metastasis (P=0.06). CONCLUSIONS The present study demonstrates the probable role of MSI in esophageal squamous cell carcinoma in the Indian population. Instability associated with the repetitive sequences--the revealing marks of loss of DNA replication fidelity may serve as an indicator of predisposition to esophageal cancer.
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Lutzker SG, Mathew R, Taller DR. A p53 dose-response relationship for sensitivity to DNA damage in isogenic teratocarcinoma cells. Oncogene 2001; 20:2982-6. [PMID: 11420711 DOI: 10.1038/sj.onc.1204394] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2000] [Revised: 02/07/2001] [Accepted: 02/13/2001] [Indexed: 11/09/2022]
Abstract
Teratocarcinomas are tumors that arise from primordial germ cells and are readily curable with DNA-damaging chemotherapeutic drugs. Teratocarcinoma cells ex vivo in tissue culture are also relatively chemosensitive and undergo apoptotic death in response to DNA damage. We have previously hypothesized that the observed sensitivity of this tumor type to DNA damage is related to high basal expression of wild-type p53 protein. We have now addressed this issue by characterizing the DNA damage response of isogenic teratocarcinoma cells that differ only in their level of expression of wild-type p53 protein. We find a clear p53 dose-response relationship in these cells for rapid apoptosis following DNA damage that correlates with diminished colony formation in clonogenic survival assays. These results suggest that strategies to increase basal wild-type p53 protein expression prior to treatment with DNA-damaging drugs may improve curability in other tumor types.
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Sood A, Mathew R, Trachtman H. Cytoprotective effect of curcumin in human proximal tubule epithelial cells exposed to shiga toxin. Biochem Biophys Res Commun 2001; 283:36-41. [PMID: 11322764 DOI: 10.1006/bbrc.2001.4749] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We conducted the following experiments to determine whether curcumin, an antioxidant compound extracted from the spice tumeric, inhibits cell death induced by Shiga toxin (Stx) 1 and 2 in HK-2 cells, a human proximal tubule cell line. Cells were incubated for 24-48 h with Stx1 or Stx2, 0-100 ng/ml. Test media contained either no further additives or 10-50 microM curcumin. Exposure to Stx1 and Stx2, 100 ng/ml, reduced cell viability to approximately 25% of control values after 24 h and 20 microM curcumin restored viability to nearly 75% of control. Cell staining confirmed that Stx1 and Stx2-induced damage in HK-2 cells involved a combination of apoptosis and necrosis. Thus, Stx1 caused apoptosis and necrosis in 12.2 +/- 2.2 and 12.7 +/- 0.9% of HK-2 cells, respectively. Similarly, Stx2 caused apoptosis and necrosis in 13.4 +/- 2.1 and 9.0 +/- 0.5% of HK-2 cells, respectively. Addition of 20 microM curcumin decreased the extent of apoptosis and necrosis to 2.9 +/- 2.0 and 3.8 +/- 0.2%, respectively in the presence of Stx1 and to 3.0 +/- 2.1 and 3.9 +/- 0.3%, respectively, for Stx2 (P < 0.01). Stx-induced apoptosis and its inhibition by curcumin were confirmed by DNA gel electrophoresis and by an assay for fragmentation. The protective effect of curcumin against Stx1 and Stx2-induced injury to HK-2 was not related to its antioxidant properties. Instead, curcumin enhanced expression of heat shock protein 70 (HSP70) in HK-2 cells under control conditions and after exposure to Stx1 or Stx2. No injury was detectable after incubation of LLC-PK(1) or OK cells, non-human proximal tubule cell lines, with Stx1 or Stx2. Thus, curcumin inhibits Stx-induced apoptosis and necrosis in HK-2 cells in vitro. The cytoprotective effect of curcumin against Stx-induced injury in cultured human proximal tubule epithelial cells may be a consequence of increased expression of HSP70.
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Mathew R, Kalyani J, Bibi R, Mallika M. Prevalence of bacterial vaginosis in antenatal women. INDIAN J PATHOL MICR 2001; 44:113-6. [PMID: 11883123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023] Open
Abstract
Bacterial vaginosis is an established risk factor in pregnant women for premature rupture of membranes and preterm delivery. This study was carried out to find out the prevalence of Bacterial Vaginosis (BV) in antenatal women with vaginal discharge and the effect of treatment with Metronidazole gel on pregnancy outcome. One hundred and fifty symptomatic and fifty asymptomatic women in second trimester of pregnancy in the age group of 20-30 years were included in the study. Gram stained smears of vaginal discharge were examined for evidence of BV with a scoring system by Nugent et al and was found to be positive in 38.5% in symptomatic antenatal women. Intravaginal metronidazole gel application was found to be an effective therapeutic option. Incidence of preterm labour was more in untreated cases.
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Mathew R, Arora S, Khanna R, Shukla NK, Mathur M, Ralhan R. Alterations in cyclin D1 expression in esophageal squamous cell carcinoma in the Indian population. J Cancer Res Clin Oncol 2001; 127:251-7. [PMID: 11315260 DOI: 10.1007/s004320000185] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
PURPOSE The p16/cyclin D1/pRb pathway plays a critical role in tumourigenesis. We recently reported alterations in expression of tumour suppressor gene products, p16 and pRb in esophageal cancer. Knowledge of alterations in cyclin D1, a vital component of this pathway in esophageal carcinomas from the Indian subcontinent, where the etiology and pathogenesis may be confounded by various unique dietary and environmental factors, is presently scanty. In order to bridge the gap between the accentuating incidence of esophageal cancer and aberrations in the components of this vital pathway, we analysed cyclin D1 expression in esophageal squamous cell carcinoma in the Indian population. METHOD Immunohistochemical analysis of cyclin D1 expression was carried out in paraffin-embedded sections of surgically resected esophageal squamous cell carcinomas (ESCC) (70 patients) and matched with histopathologically normal esophageal tissues from a distant site. The findings were correlated with clinicopathological parameters. RESULTS Overexpression of cyclin D1 was observed in the tumour nuclei in 41 out of 70 (59%) patients. We found concomitant alterations in 16 and cyclin D1 (p16-/CycD1+ phenotype) in 16 of the 70 patients (23%), while alterations of pRb and cyclin D1 (pRb-/CycD1+) were observed in 36 of the 70 (51%) patients of ESCCs. Cyclin D1 overexpression was significantly associated with the loss of p16 immunoreactivity (P = 0.005). The pRb- and p16-/pRb-/Cyc D+ phenotypes showed significant association with differentiation of the tumour (P = 0.005, 0.05, respectively). Kaplan-Meier analysis for disease recurrence showed increased disease recurrence in cyclin D1 overexpressed patients. Median time to disease recurrence in the cyclin D1+ group was 15 months as against 18 months observed in the cyclin D1- patients (P = 0.067; log-rank test). CONCLUSION Alterations in at least one of the components of the p16/cyclin D1/pRb pathway in majority of the 70 patients analysed herein, and concomitant alterations in all the three proteins in 19 patients (35%) underscore the critical role of this pathway in esophageal tumourigenesis. The results of the present study taken together with our previous findings on p16 and pRb alterations in ESCCs suggest that these alterations are not mutually exclusive and may cooperatively provide greater tumour growth advantage. The prognostic significance of alterations in the expression of these components cyclin D1, p16, and pRb remains to be established in a larger cohort.
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Arora S, Mathew R, Mathur M, Chattopadhayay TK, Ralhan R. Alterations in MDM2 expression in esophageal squamous cell carcinoma: relationship with p53 status. Pathol Oncol Res 2001; 7:203-8. [PMID: 11692147 DOI: 10.1007/bf03032350] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
In view of the significance of MDM2 as a regulator as well as critical target of wild type p53, this study was undertaken to determine the alteration in MDM2 expression in esophageal squamons cell carcinoma (ESCC) and its relationship to clinicopathological parameters as well as p53gene and protein status. Immunohistochemical analysis of MDM2 and p53 proteins on paraffin embedded sections from 64 surgically resected ESCCs and matched histologically normal tissues showed overexpression of MDM2 protein in 23/64 (36%) ESCCs, while the histopathologically normal esophageal tissues did not show detectable level of MDM2 immunoreactivity. Interestingly, MDM2 /p53 + phenotype was observed in 37/64 (58%) cases. None of the cases with p53 mis-sense mutations (12/30, 40%) showed detectable level of MDM2 protein. Missense p53 mutations were significantly associated with discordant p53 + /MDM2 immunophenotype (p= 0.004). The most intriguing feature of the study was accumulation of MDM2 in the absence of detectable p53 in 11% of and overexpression of MDM2 and p53 in 25% of ESCCs, suggesting a p53-independent role for MDM2 in a subset of tumors. These results underscore the involvement of MDM2 in p53-dependent and -independent pathways in the pathogenesis of esophageal cancer in the Indian population.
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Bhandari R, Mathew R, Vijayachandra K, Visweswariah S. Tyrosine phosphorylation of the human guanylyl cyclase C receptor. J Biosci 2000; 25:339-46. [PMID: 11120586 DOI: 10.1007/bf02703787] [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: 11/25/2022]
Abstract
Tyrosine phosphorylation events are key components of several cellular signal transduction pathways. This study describes a novel method for identification of substrates for tyrosine kinases. Co-expression of the tyrosine kinase EphB1 with the intracellular domain of guanylyl cyclase C (GCC) in Escherichia coli cells resulted in tyrosine phosphorylation of GCC, indicating that GCC is a potential substrate for tyrosine kinases. Indeed, GCC expressed in mammalian cells is tyrosine phosphorylated, suggesting that tyrosine phosphorylation may play a role in regulation of GCC signalling. This is the first demonstration of tyrosine phosphorylation of any member of the family of membrane-associated guanylyl cyclases.
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Kapoor S, Mathew R, Huilgol NG, Kagiya TV, Nair CK. Redox reactions of sanazole (AK-2123) in aqueous solutions: a pulse radiolysis study. JOURNAL OF RADIATION RESEARCH 2000; 41:355-366. [PMID: 11329884 DOI: 10.1269/jrr.41.355] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The redox chemistry of sanazole, an efficient hypoxic cell radiosensitizer, generally referred to as AK-2123, was studied by pulse radiolysis with eaq-, CO2-., 2-propanol radicals and CH2OH radicals. AK-2123 reacts with eaq-, CO2-. and 2-propanol radicals at almost diffusion-controlled rates, producing a nitro radical anion (lambda max = 290 nm) within a few microseconds. The decay kinetics of the radical anion was independent of the pH. The radical anion reacts with oxygen with a rate constant of 3.4 x 10(6) dm3 mol-1 s-1. An electron-transfer reaction was observed from the thymine radical anion to AK-2123. From redox equilibria with methyl viologen, the one-electron reduction potential of AK-2123 in aqueous solution, determined by pulse radiolysis, was estimated to be -0.33 +/- 0.02 V vs. NHE. Depletion of intracellular nonprotein thiols did not mitigate the radiosensitizing affect of the hypoxic radiosensitizer, AK-2123.
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Kane GR, Keshavamurthy CB, Sethi RB, Mathew R. Troponin-T in unstable angina--a clinical and angiographic study. THE JOURNAL OF THE ASSOCIATION OF PHYSICIANS OF INDIA 2000; 48:1074-7. [PMID: 11310384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
OBJECTIVE To examine the prognostic significance of Troponin-T in patients admitted with unstable angina and to study their angiographic morphology. DESIGN Single centre, prospective study of in hospital events. SETTING Intensive coronary care unit of a large municipal general hospital. SUBJECTS 128 consecutive patients admitted with a diagnosis of unstable angina (Braunwald's classification). METHODS Measurement of Troponin-T by qualitative assay at admission, coronary angiography between 5th to 7th day. MAIN OUTCOME MEASURES In hospital adverse cardiac events--recurrent angina, new myocardial infarction or cardiac deaths. RESULTS Fifty six (43.7%) patients had a positive test. The incidence of recurrent angina was significantly higher in the Trop-T positive group (57.1% vs 11.1%, p < 0.001). Six patients of this developed acute myocardial infarction subsequently whereas none of the patients in the Trop-T negative group developed acute MI (10.7% v/s 0%, p = 0.05). There were two deaths in the Trop-T positive group and none in the Trop-T negative group. 44 (78.5%) patients of the Trop-T positive group and 60 patients in the Trop-T negative group underwent coronary angiography. There was no significant difference in the incidence of single vessel disease (27.2% v/s 20%, p = NS) or multivessel disease (72.7% v/s 69.9%, p = ns). None of the patients with a positive Trop-T had normal coronary angiography whereas 6 patients in the Trop-T negative group had a normal coronary angiography (0% v/s 10%, p < 0.05). Patients with a positive troponin T test had a significantly higher incidence of type B lesions and a higher incidence of intracoronary thrombus. CONCLUSIONS The in hospital outcome of Trop-T positive patients was significantly worse than patients with a negative test. Patients with a positive troponin T test had more complex coronary morphology and a higher incidence of intracoronary thrombus. We conclude that troponin-T can be used as a prognostic marker in patients with unstable angina.
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Ralhan R, Mathew R, Arora S, Bahl R, Shukla NK, Mathur M. Frequent alterations in the expression of tumor suppressor genes p16INK4A and pRb in esophageal squamous cell carcinoma in the Indian population. J Cancer Res Clin Oncol 2000; 126:655-60. [PMID: 11079730 DOI: 10.1007/s004320000147] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
PURPOSE Alterations in the cell cycle regulatory p16INK4a/Cyclin D1/pRb pathway play a pivotal role in tumorigenesis. Knowledge of alterations in the tumor suppressor protein pRb and its negative regulator, p16CDKN2/MTS1/INK4a in esophageal squamous cell carcinoma (ESCC) from the Indian subcontinent is meager. To gain insight into the mechanisms underlying tumorigenesis and to search for diagnostic molecular markers for ESCC, we analyzed the expression of p16INK4a and pRb in ESCCs in the Indian population. METHODS Immunohistochemical analysis of pRb and p16INK4a proteins was carried out in paraffin-embedded sections from 61 surgically resected ESCCs and matched normal tissues, and the results correlated with clinicopathological parameters using chi square and Fisher's exact tests. Dual immunohistochemical analysis has been carried out to demonstrate the concomitant loss of expression of p16INK4a and pRb. RESULTS Fifty-nine of 61 (97%) cases showed aberration(s) in either or both of these proteins confirming their critical role in esophageal tumorigenesis. Loss of pRb was observed in 51 of the 61 (84%) and loss of p16INK4a was observed in 35 of 61 (57%) cases. Loss of pRb showed significant association with dedifferentiation of the tumor (P = 0.004). p16-/pRb-, and p16+/pRb- phenotypes were significantly associated with nodal metastasis (P = 0.017 and 0.027, respectively), while p16-/pRb+ phenotype was associated with dedifferentiation of the tumor (P = 0.012). CONCLUSION pRb/p16INK4a pathway plays a critical role in esophageal tumorigenesis in the Indian population. The dual hits (concomitant loss) of pRb and p16INK4a expression suggest that these two components are not mutually exclusive, and can both be altered in a significant proportion of primary ESCCs serving as putative diagnostic markers for esophageal cancer. However, the impact of dual hit on tumor behavior and disease prognosis remains to be determined.
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Salvino JM, Kumar NV, Orton E, Airey J, Kiesow T, Crawford K, Mathew R, Krolikowski P, Drew M, Engers D, Krolikowski D, Herpin T, Gardyan M, McGeehan G, Labaudiniere R. Polymer-supported tetrafluorophenol: a new activated resin for chemical library synthesis. JOURNAL OF COMBINATORIAL CHEMISTRY 2000; 2:691-7. [PMID: 11126297 DOI: 10.1021/cc0000491] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A new tetrafluorophenol activated resin that facilitates the use of 19F NMR to quantitate loading is presented. This new resin provides a useful tool for acylation, and a novel activated polymeric sulfonate ester to generate sulfonamides. This activated resin reacts with a wide scope of N-nucleophiles including primary and secondary amines, and anilines. This new activated resin methodology provides a powerful tool for pure single-compound library synthesis.
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Mathew R, Gewitz MH. Pulmonary hypertension in infancy and childhood. HEART DISEASE (HAGERSTOWN, MD.) 2000; 2:362-8. [PMID: 11728283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/17/2023]
Abstract
Abnormalities of pulmonary artery pressure and resistance continue to complicate many varieties of cardiovascular problems in childhood. Much recent effort has been devoted to understanding the cellular mechanisms underlying the pathophysiology of pulmonary hypertension, centering on endothelial cell dysfunction as a principal factor. Defects in the vasodilation machinery of the endothelial cell, such as overexpression of vasoconstrictor elements, have been implicated in various forms of pulmonary hypertension. This includes pulmonary hypertension that is secondary to congenital heart disease, and the primary forms that occur in older children and in neonates. In addition, experimental methods assessing cyclic adenosine monophosphate-mediated and cyclic guanosine monophosphate-mediated vasoreactivity suggest a possible genetic basis in the responses of the pulmonary microvasculature. This article reviews some of the current information that has been developed along these lines, and explores the implications of these data for therapeutic strategies to treat this complex problem.
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Mathew R, Santha T. The treatment of WHO Category 1 tuberculosis with 2HRZE/6HE is indeed defensible. Int J Tuberc Lung Dis 2000; 4:795. [PMID: 10985647] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023] Open
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Parris KD, Lin L, Tam A, Mathew R, Hixon J, Stahl M, Fritz CC, Seehra J, Somers WS. Crystal structures of substrate binding to Bacillus subtilis holo-(acyl carrier protein) synthase reveal a novel trimeric arrangement of molecules resulting in three active sites. Structure 2000; 8:883-95. [PMID: 10997907 DOI: 10.1016/s0969-2126(00)00178-7] [Citation(s) in RCA: 188] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND Holo-(acyl carrier protein) synthase (AcpS), a member of the phosphopantetheinyl transferase superfamily, plays a crucial role in the functional activation of acyl carrier protein (ACP) in the fatty acid biosynthesis pathway. AcpS catalyzes the attachment of the 4'-phosphopantetheinyl moiety of coenzyme A (CoA) to the sidechain of a conserved serine residue on apo-ACP. RESULTS We describe here the first crystal structure of a type II ACP from Bacillus subtilis in complex with its activator AcpS at 2.3 A. We also have determined the structures of AcpS alone (at 1.8 A) and AcpS in complex with CoA (at 1.5 A). These structures reveal that AcpS exists as a trimer. A catalytic center is located at each of the solvent-exposed interfaces between AcpS molecules. Site-directed mutagenesis studies confirm the importance of trimer formation in AcpS activity. CONCLUSIONS The active site in AcpS is only formed when two AcpS molecules dimerize. The addition of a third molecule allows for the formation of two additional active sites and also permits a large hydrophobic surface from each molecule of AcpS to be buried in the trimer. The mutations Ile5-->Arg, Gln113-->Glu and Gln113-->Arg show that AcpS is inactive when unable to form a trimer. The co-crystal structures of AcpS-CoA and AcpS-ACP allow us to propose a catalytic mechanism for this class of 4'-phosphopantetheinyl transferases.
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Salvino JM, Mathew R, Kiesow T, Narensingh R, Mason HJ, Dodd A, Groneberg R, Burns CJ, McGeehan G, Kline J, Orton E, Tang SY, Morrisette M, Labaudininiere R. Solid-phase synthesis of an arylsulfone hydroxamate library. Bioorg Med Chem Lett 2000; 10:1637-40. [PMID: 10937713 DOI: 10.1016/s0960-894x(00)00285-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Synthesis of an arylsulfone hydroxamate lead optimization library is presented. Biological activity of representative examples is given to demonstrate the value of this approach for lead optimization.
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Kane GR, Patil CV, Sahoo PK, Bhatnagar D, Mathew R, Sethi RB. Coronary stenting in diabetics: six months clinical and angiographic outcome. Indian Heart J 2000; 52:416-20. [PMID: 11084782] [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] Open
Abstract
The aim of this study was to assess the clinical and angiographic outcome of coronary stenting in diabetics as compared to non-diabetic patients. A total of 114 patients undergoing coronary angioplasty with stenting were prospectively evaluated. There were 30 diabetic (group A) and 84 non-diabetic (group B) patients. There were no significant differences in both the groups with respect to other risk factors and clinical characteristics. Both the groups were also comparable in terms of lesion morphology and stent types. The clinical endpoints were recurrent angina, reinfarction, cardiac death and need for target vessel revascularisation. The angiographic endpoint was angiographic restenosis at six months. There were 70 males and 44 female patients with a mean age of 55 +/- 12 years. Angiographic follow-up was completed in 85 (74.7%) patients which included 25 (83.3%) patients in group A and 60 (71.4%) in group B. Among clinical events at 30 days, the incidence of recurrent angina was 10.0 percent versus 8.3 percent (group A and B; p = NS) and incidence of reinfarction was 6.6 percent versus 5.9 percent (group A and B; p = NS), respectively. At six months, recurrent angina was seen in 16.6 percent versus 15.4 percent (p = NS) and reinfarction was seen in 10.0 percent versus 8.3 percent (p = NS) in group A and B, respectively. There were no deaths in either group. The angiographic restenosis rate was significantly higher in diabetics compared to non-diabetics (40.0% vs 23.3%; p = 0.02). The need for target vessel revascularisation was higher in diabetics as compared to non-diabetics (16.0% vs 6.6%; p = 0.03). We conclude that in spite of using coronary stents, the diabetics have higher restenosis rate and higher target vessel revascularisation rate than the non-diabetic patients.
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Wilson W, Mathew R, Turkington T, Hawk T, Coleman RE, Provenzale J. Brain morphological changes and early marijuana use: a magnetic resonance and positron emission tomography study. J Addict Dis 2000; 19:1-22. [PMID: 10772599 DOI: 10.1300/j069v19n01_01] [Citation(s) in RCA: 174] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
BACKGROUND The focus of this report is on the possible role that the age of first use of marijuana may play on brain morphology and function. METHODS Magnetic resonance imaging (MRI) and positron emission tomography (PET) were utilized to study 57 subjects. Brain volume measures (whole brain, gray matter, white matter and lateral ventricle volumes), global cerebral blood flow (CBF) and body size were evaluated. RESULTS There are three primary findings related to age of first use of marijuana. Subjects who started using marijuana before age 17, compared to those who started later, had smaller whole brain and percent cortical gray matter and larger percent white matter volumes. Functionally, males who started using marijuana before 17 had significantly higher CBF than other males. Both males and females who started younger were physically smaller in height and weight, with the effects being greater in males. CONCLUSIONS These findings suggest that the age at which exposure to marijuana begins is important. Early adolescence may be a critical period for effects that are not present when exposure begins later. These results are discussed in light of reported effects of marijuana on gonadal and pituitary hormones.
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Mathew R, Fan NY, Yuan N, Chander PN, Gewitz MH, Stier CT. Inhibition of NOS enhances pulmonary vascular changes in stroke-prone spontaneously hypertensive rats. Am J Physiol Lung Cell Mol Physiol 2000; 278:L81-9. [PMID: 10645894 DOI: 10.1152/ajplung.2000.278.1.l81] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
To determine the effects of chronic nitric oxide (NO) blockade on the pulmonary vasculature, 58-day-old spontaneously hypertensive rats of the stroke-prone substrain (SHRSP) and Wistar-Kyoto rats (WKY) received N(omega)-nitro-L-arginine (L-NNA; 15 mg. kg(-1). day(-1) orally for 8 days). Relaxation to acetylcholine (ACh) in hilar pulmonary arteries (PAs), the ratio of right ventricular (RV) to body weight (RV/BW) to assess RV hypertrophy (RVH), and the percent medial wall thickness (WT) of resistance PAs were examined. L-NNA did not alter the PA relaxation, RV/BW, or WT in WKY. Although the PA relaxation and RV/BW in control SHRSP were comparable to those in WKY, the WT was increased (31 +/- 2 vs. 19 +/- 1%). L-NNA-treated SHRSP showed two patterns: in one group, the relaxation, RV/BW, and WT were comparable to those in the control SHRSP; in the other, impaired relaxation (36 +/- 7 vs. 88 +/- 4% for WKY) was associated with an increase in WT (37 +/- 1%) and RV/BW (0. 76 +/- 0.05). Thus the abnormal pulmonary vasculature in SHRSP at <10 wk of age is not accompanied by impaired relaxation in PAs or RVH; however, impaired relaxation is associated with increased WT and RVH.
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Mathew R, Ranjit MS, Rajamani MR. Postoperative endocarditis due to Candida tropicalis. THE JOURNAL OF THE ASSOCIATION OF PHYSICIANS OF INDIA 1999; 47:921-2. [PMID: 10778665] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
In conclusion, we emphasize the importance of isolating the fungal agent from repeated blood cultures, particularly in infective endocarditis following heart surgeries.
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Bhargava A, Kumar A, Yuan N, Gewitz MH, Mathew R. Monocrotaline induces interleukin-6 mRNA expression in rat lungs. HEART DISEASE (HAGERSTOWN, MD.) 1999; 1:126-32. [PMID: 11720614] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
Monocrotaline-induced pulmonary hypertension (PH) in rats is preceded by an inflammatory response in the lungs, and interleukin-6 (IL-6) is expressed in response to inflammation. To evaluate the role of IL-6 in monocrotaline-induced PH, rats received a single subcutaneous injection of monocrotaline (60 mg/kg) or an equivalent amount of normal saline. Pulmonary artery pressure (Ppa), right ventricular hypertrophy (RVH), expression of IL-6 mRNA, and bioactivity of IL-6 in the lungs of these rats were examined 48 hours and 1 and 2 weeks after administration of monocrotaline. The effects of dexamethasone treatment on monocrotaline-induced PH also were evaluated. Two weeks after administration of monocrotaline, significant PH and RVH developed in these rats. Reverse transcription-polymerase chain reaction (RT-PCR) revealed expression of IL-6 mRNA in the lungs 48 hours and 1 and 2 weeks after administration of monocrotaline. This was confirmed using ribonuclease protection assay. The bioactivity of IL-6 in lung extracts progressively increased. Dexamethasone markedly inhibited expression of IL-6 mRNA and IL-6 bioactivity in the lungs, with concomitant attenuation of monocrotaline-induced PH and RVH. Our data show that monocrotaline induces expression of IL-6 mRNA in rat lungs and that inhibition of IL-6 results in attenuation of PH. These findings indicate that IL-6 may play a role in the pathogenesis of PH.
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Dent A, Evans J, Newton M, Corker J, Russell A, Abdul Rahman MB, Fiddy S, Mathew R, Farrow R, Salvini G, Atkinson P. High-quality energy-dispersive XAFS on the 1 s timescale applied to electrochemical and catalyst systems. JOURNAL OF SYNCHROTRON RADIATION 1999; 6:381-383. [PMID: 15263315 DOI: 10.1107/s0909049599002150] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/1998] [Accepted: 02/02/1999] [Indexed: 05/24/2023]
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Arnsten AF, Mathew R, Ubriani R, Taylor JR, Li BM. Alpha-1 noradrenergic receptor stimulation impairs prefrontal cortical cognitive function. Biol Psychiatry 1999; 45:26-31. [PMID: 9894572 DOI: 10.1016/s0006-3223(98)00296-0] [Citation(s) in RCA: 193] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
BACKGROUND Many neuropsychiatric disorders are associated with high levels of noradrenergic turnover, and most antipsychotic medications have alpha-1 adrenoceptor blocking properties, yet little is known about alpha-1 influences on higher cortical function. METHODS The alpha-1 adrenergic agonist, phenylephrine, was infused into the prefrontal cortex (PFC) of rats (0.1 microgram/0.5 microL) performing a spatial working memory task, delayed alternation. The phenylephrine response was challenged with coinfusion of the alpha-1 adrenergic antagonist, uripidil (0.01 microgram), or with a dose of lithium chloride (4 mEq/kg, i.p., 18 hours) known to suppress phosphotidylinositol (PI) turnover, the second messenger pathway coupled to alpha-1 adrenoceptors. RESULTS Phenylephrine infusions in PFC markedly impaired delayed alternation performance. The phenylephrine response was reversed by coinfusion of uripidil, or by pretreatment with lithium, consistent with actions at alpha-1 adrenoceptors coupled to a PI pathway. CONCLUSIONS These findings demonstrate that alpha-1 adrenoceptor stimulation in the PFC impairs cognitive function. Excessive stimulation of alpha-1 adrenoceptors may contribute to PFC deficits (e.g., distractibility, impulsivity) in disorders such as mania, dementia, and anxiety associated with high noradrenergic turnover.
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Hulme C, Mathew R, Moriarty K, Miller B, Ramanjulu M, Cox P, Souness J, Page KM, Uhl J, Travis J, Labaudiniere R, Huang F, Djuric SW. Orally active indole N-oxide PDE4 inhibitors. Bioorg Med Chem Lett 1998; 8:3053-8. [PMID: 9873675 DOI: 10.1016/s0960-894x(98)00572-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This communication describes the synthesis and in vitro and in vivo evaluation of a novel potent series of phosphodiesterase type (IV) (PDE4) inhibitors. Several of the compounds presented possess low nanomolar IC50's for PDE4 inhibition and excellent in vivo activity for inhibition of TNF-alpha levels in LPS challenged mice (mouse endotoxemia model). Emesis studies (dog) and efficacy in a SCW arthritis model for the most potent PDE4 inhibitors are presented.
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98
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Hulme C, Moriarty K, Miller B, Mathew R, Ramanjulu M, Cox P, Souness J, Page KM, Uhl J, Travis J, Huang FC, Labaudiniere R, Djuric SW. The synthesis and biological evaluation of a novel series of indole PDE4 inhibitors I. Bioorg Med Chem Lett 1998; 8:1867-72. [PMID: 9873449 DOI: 10.1016/s0960-894x(98)00324-2] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
This communication describes the synthesis and in vitro evaluation of a novel potent series of phosphodiesterase type (IV) (PDE4) inhibitors. The compounds described contain an indole moiety which replaces the 'rolipram-like' 3-methoxy-4-cyclopentoxy motif. Several of the compounds presented possess low nanomolar IC50's for PDEIV inhibition. In vivo activities determined from measurement of serum TNF-alpha levels in LPS challenged mice (mouse endotoxemia model) are also reported.
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99
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Kane GR, Mathew R, Chakrapani BS, Waykole M, Sahu P. Thrombotic complications during coronary angiography associated with use of non-ionic contrast media. Indian Heart J 1998; 50:433-5. [PMID: 9835205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023] Open
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100
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Mathew R, Kacew S, Khan SU. Bioavailability in rats of bound pesticide residues from tolerant or susceptible varieties of soybean and canola treated with metribuzin or atrazine. CHEMOSPHERE 1998; 36:589-96. [PMID: 9451811 DOI: 10.1016/s0045-6535(97)00367-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Susceptible or tolerant varieties of soybean treated with metribuzin, or canola treated with atrazine were grown in a controlled environment. Shoots and fruits were harvested at maturity and extracted exhaustively with methanol. The extracted materials containing bound 14C residues were subsequently fed to rats for two days. The elimination of 14C in urine and feces was monitored for 4 days and the distribution of radioactivity in liver, kidney and heart was studied. Higher 14C residues in urine were present in animals fed fruits compared to shoots of soybean or canola of both susceptible and tolerant varieties. The bound atrazine residues from the pods of Atr Tower (tolerant variety of canola) were more bioavailable than Tower (susceptible variety of canola). Bioavailability of bound atrazine from the shoots of canola in both varieties was very low. In soybean fed animals, bound metribuzin derived 14C from the susceptible variety (Maple Amber) was more bioavailable than from the resistant variety (Maple Arrow). However, feeding the animals with susceptible or tolerant varieties of soybean or canola containing bound residues of 14C metribuzin or 14C atrazine for two days did not result in the accumulation of radioactivity in the body organs studied. Thus our data show that the bioavailability of these bound pesticides was dependent on the type of plant parts ingested and the variety of plant species.
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