101
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Juneja MS, Arunkumar N, Srinivas CN, Rajan S, Ajit M. Right atrial myxoma arising from the inferior vena cava. Indian Heart J 2006; 58:356-358. [PMID: 19039156] [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
A middle-aged man presented with recent-onset dyspnea and recurrent syncopal attacks at our institute. Echocardiography revealed a large mass arising from the inferior vena cava and prolapsing into the right atrium and ventricle. Histopathologic examination revealed the classic features of a myxoma. This report is of a rare case of a cardiac myxoma arising from the inferior vena cava.
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102
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Zhu YB, Rajan S, Kurian VM, Liu ZY. Surgical outcomes and strategy of hypertrophic obstructive cardiomyopathy. J Zhejiang Univ Sci B 2006; 7:148-53. [PMID: 16421972 PMCID: PMC1363760 DOI: 10.1631/jzus.2006.b0148] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
OBJECTIVE To evaluate the surgical clinical results of hypertrophic obstructive cardiomyopathy. METHODS We retrospectively collected data on 24 patients who underwent surgical management in the past ten years in two hospitals in China and Madras Medical Mission in India. Myomectomy was carried out on all patients. Among them 3 patients underwent mitral valve replacement; 2 patients underwent mitral valve repair (anterior mitral leaflet plication); 2 patients underwent aortic valve replacement; 1 patient underwent aortic valve repair; 2 patients underwent aortic root replacement; 1 patient underwent Bentall's procedure and 1 patient underwent coronary artery bypass grafting because of a breached muscle bridge. RESULTS One patient died of post-operative heart failure. The mean follow-up time was 4.3 years. There was significant improvement in the symptomatic status. Sixteen patients were asymptomatic with good effort tolerance and only four patients had New York heart association (NYHA) Classes I-II due to associated valvular lesions. CONCLUSION Our experience proved that symptomatic hypertrophic obstructive cardiomyopathy or non-symptomatic hypertrophic obstructive cardiomyopathy with combined heart disease is indication for surgery as surgical intervention could get better clinical results in this kind of patients compared with other non-surgical method because it beneficially reduces the systolic anterior motion (SAM) of the mitral valve leaflet, which could not be avoided by other non-surgical treatment.
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Rosemary J, Surendiran A, Rajan S, Shashindran CH, Adithan C. Influence of the CYP2C9 AND CYP2C19 polymorphisms on phenytoin hydroxylation in healthy individuals from south India. Indian J Med Res 2006; 123:665-70. [PMID: 16873909] [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] Open
Abstract
BACKGROUND AND OBJECTIVES Phenytoin, a widely used anti-epileptic drug, is metabolized mainly by CYP2C9 (90%) and partly by CYP2C19 (10%) to its major metabolite 5-(para-hydroxyphenyl)-5- phenylhydantoin (p-HPPH). The CYP2C9 and CYP2C19 genes encoding these enzymes are polymorphically expressed and most of the variants result in decreased metabolism of the respective substrates. The present study was undertaken to investigate the influence of the CYP2C9*2 and *3 as well as CYP2C19*2 and *3 variant genotypes on phenytoin hydroxylation in healthy subjects from south India. METHODS A total of 27 healthy, unrelated, subjects were administered a single oral dose of 300 mg phenytoin. Four hours later, 5 ml of blood was collected and genotyped for CYP2C9*1, *2, *3, CYP2C19*1, *2 and *3 by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Phenytoin and the major metabolite p-HPPH were estimated by reverse phase HPLC. The metabolic ratio was calculated as concentration of phenytoin/p-HPPH. RESULTS A significant correlation was observed between the CYP2C9 genotype and metabolic ratio of phenytoin/p-HPPH (r = 0.472, 95% CI 0.100 to 0.728; P = 0.01). While no association was found with CYP2C19 alone, a significant correlation was observed between the combined CYP2C9 and CYP2C19 genotypes and phenytoin metabolic ratio (r = 0.507, 95% CI 0.146 to 0.749; P< 0.01). INTERPRETATION AND CONCLUSION CYP2C9*2 and *3 mutant alleles caused decreased hydroxylation of phenytoin in vivo, whereas the mutant alleles of CYP2C19 played only a minor role in the metabolism of phenytoin in subjects of our study. The results of present preliminary study needs to be confirmed with a larger sample.
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Rajan S, Ahn J, Balasubramaniam VM, Yousef AE. Combined pressure-thermal inactivation kinetics of Bacillus amyloliquefaciens spores in egg patty mince. J Food Prot 2006; 69:853-60. [PMID: 16629029 DOI: 10.4315/0362-028x-69.4.853] [Citation(s) in RCA: 109] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Bacillus amyloliquefaciens is a potential surrogate for Clostridium botulinum in validation studies involving bacterial spore inactivation by pressure-assisted thermal processing. Spores of B. amyloliquefaciens Fad 82 were inoculated into egg patty mince (approximately 1.4 x 10(8) spores per g), and the product was treated with combinations of pressure (0.1 to 700 MPa) and heat (95 to 121 degrees C) in a custom-made high-pressure kinetic tester. The values for the inactivation kinetic parameter (D), temperature coefficient (zT), and pressure coefficient (zP) were determined with a linear model. Inactivation parameters from the nonlinear Weibull model also were estimated. An increase in process pressure decreased the D-value at 95, 105, and 110 degrees C; however, at 121 degrees C the contribution of pressure to spore lethality was less pronounced. The zP-value increased from 170 MPa at 95 degrees C to 332 MPa at 121 degrees C, suggesting that B. amyloliquefaciens spores became less sensitive to pressure changes at higher temperatures. Similarly, the zT-value increased from 8.2 degrees C at 0.1 MPa to 26.8 degrees C at 700 MPa, indicating that at elevated pressures, the spores were less sensitive to changes in temperature. The nonlinear Weibull model parameter b increased with increasing pressure or temperature and was inversely related to the D-value. Pressure-assisted thermal processing is a potential alternative to thermal processing for producing shelf-stable egg products.
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105
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Shuvalova L, Minasov G, Rajan S, Brunzelle JS, Yang X, Anderson WF. When structures of unknown proteins are determined, what is next? Acta Crystallogr A 2005. [DOI: 10.1107/s0108767305089002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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106
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Leong SS, Wee J, Rajan S, Poon D, Toh CK, Lim D, Tay MH, Foo KF, Tan EH. Triplet combination of gemcitabine, paclitaxel, and carboplatin followed by maintenance 5-fluorouracil and leucovorin in patients with metastatic nasopharyngeal carcinoma. J Clin Oncol 2005. [DOI: 10.1200/jco.2005.23.16_suppl.5572] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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107
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Aggarwal BK, Rajan S, Aggarwal A, Gothi R, Sharma R, Tandon V. CT diagnosis of Meckel diverticulum in a paracolic internal hernia. ACTA ACUST UNITED AC 2005; 30:56-9. [PMID: 15759325 DOI: 10.1007/s00261-004-0200-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The autopsy incidence of internal hernia has been reported to be between 0.2% and 0.9%, and these hernias are usually diagnosed on imaging due to their complications or at surgery. Meckel diverticulum is the most common congenital anomaly of the gastrointestinal tract, occurring in 1% to 3% of the population according to autopsy studies. The condition also is usually diagnosed at surgery, by barium studies or scintigraphy, or on cross-sectional imaging due to complications. We present an unusual case of a large Meckel diverticulum in a right paracolic hernia diagnosed on multidetector computed tomography. This diagnosis was made after attacks of subacute intestinal obstruction with the aid of multiplanar reconstructions. This case emphasizes the role of multidetector computed tomography and postprocessing techniques such as multiplanar reconstruction in the diagnosis of bowel pathology.
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108
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Gothi R, Kapur R, Rajan S, Aggarwal A, Aggarwal B. Radiological quiz - musculoskeletal. Indian J Radiol Imaging 2005. [DOI: 10.4103/0971-3026.29169] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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109
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Aggarwal BK, Panwar S, Rajan S, Aggarwal A, Ahlawat K. Varied appearances & signal characteristics of leiomyomas on MR imaging. Indian J Radiol Imaging 2005. [DOI: 10.4103/0971-3026.28820] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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110
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Lim ST, Tao M, Cheung YB, Rajan S, Mann B. Can patients with early-stage diffuse large B-cell lymphoma be treated without bone marrow biopsy? Ann Oncol 2005; 16:215-8. [PMID: 15668272 DOI: 10.1093/annonc/mdi050] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Data on the incidence of bone marrow (BM) involvement in early-stage diffuse large B-cell lymphoma (DLBCL) are lacking. Although BM biopsy is a safe procedure, it is often poorly tolerated. This analysis aims to assess the incidence of BM involvement and to identify parameters predicting BM involvement in early-stage DLBCL. PATIENTS AND METHODS One hundred and ninety-two patients with radiological stages 1 and 2 disease were analysed. The data collected were age, sex, presence of B symptoms, white blood cell (WBC) count, platelet count, haemoglobin (Hb), serum lactate dehydrogenase level, serum beta(2)-microglobulin level, presence of extranodal disease, and the presence of bulky disease (defined as >7 cm). RESULTS Overall incidence of BM involvement was 3.6%. Hb < 10 g/dl (P=0.02), WBC count < 4 x 10(9)/l (P=0.007) and bulky disease (P=0.06) were found to be predictive of BM involvement. Among the 120 patients without any of these three factors, only one patient had BM involvement (0.83%; 95% confidence interval 0.02% to 4.6%). The absence of all three factors gave a negative predictive value of 99.2%. Overall 3-year survival for patients without all three risk factors was 80%. CONCLUSIONS BM biopsy may be safely omitted in selected patients with early-stage DLBCL.
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Powers SW, Patton SR, Rajan S. A comparison of food group variety between toddlers with and without cystic fibrosis. J Hum Nutr Diet 2004; 17:523-7. [PMID: 15546429 DOI: 10.1111/j.1365-277x.2004.00560.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVES To compare the food group variety and nutritional adequacy of the diet between toddlers with cystic fibrosis (CF) and age-matched controls. Subjects A clinical sample of 22 toddlers with CF (mean age=21.3 +/- 7.2 months) matched to a community sample of 22 healthy peers. MAIN OUTCOME MEASURES The variety index for toddlers (VIT) and the mean adequacy ratio (MAR). RESULTS Fruit group scores were highest for children with CF (0.95 +/- 0.13; possible range 0.00-1.00), and dairy group scores were highest for controls (0.90 +/- 0.18). All children earned the lowest scores for vegetables (CF: 0.15 +/- 0.12; controls: 0.26 +/- 0.22). No significant differences were found when comparing VIT and MAR scores by sample (P >0.05). A moderate positive relationship was found between total VIT scores and MAR scores for all children (r=0.38, P <0.05). Toddlers with CF did not achieve the 120-150% of Recommended Dietary Allowance (RDA) for energy. CONCLUSIONS Toddlers with CF are consuming diets that are varied and nutritionally adequate for a healthy child. To optimize nutritional status and growth, current recommendations for toddlers with CF to eat a well-balanced diet and to exceed daily RDA for energy requirements remain key dietary issues.
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Modi R, Ram R, Keshavamurthy S, Sankar VM, Kurian M, Rajan S. Postmyocardial infarction ventricular septal defect—Clinical profile and management. Indian J Thorac Cardiovasc Surg 2004. [DOI: 10.1007/s12055-004-0325-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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113
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Madhu Sankar N, Kurian VM, Rajan S, Ninan B, Ajit M, Cherian KM. Heart-lung transplantation in India: initial experience. Indian Heart J 2003; 55:185-7. [PMID: 12921339] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/04/2023] Open
Abstract
Heart-lung transplantation is a well accepted and standard form of therapy for the surgical management of patients with end-stage cardiopulmonary disorders. The first heart-lung transplant in India was performed at our institution on May 3, 1999 and, subsequently, 2 more patients have undergone this procedure. The initial experience is encouraging and heralds a new era of thoracic organ transplantation in India.
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114
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Badami S, Rai SR, Moorkoth S, Rajan S, Suresh B. Pharmacognostical Evaluation of Caesalpinia sappan Heartwood. Anc Sci Life 2003; 23:100-7. [PMID: 22557119 PMCID: PMC3330961] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2003] [Accepted: 07/27/2003] [Indexed: 11/01/2022] Open
Abstract
Caesalpinia span heartwood is used in folklore in India. The present work attempts to summarize the pharmacognostical characters of the heartwood of this plant. Ash and extractive values, phytochemical tests, HPTLC and fluorescence analysis were carried out. The present work contributes for the standardization of this medicinal heat wood.
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Badami S, Aneesh R, Sankar S, Sathishkumar MN, Suresh B, Rajan S. Antifertility activity of Derris brevipes variety coriacea. JOURNAL OF ETHNOPHARMACOLOGY 2003; 84:99-104. [PMID: 12499083 DOI: 10.1016/s0378-8741(02)00288-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Traditional physicians in and around Kotagiri village near Ootacamund, use a mixture of powdered roots of Cassia occidentalis, Derris brevipes variety coriacea and Justicia simplex to control female fertility. A mixture of powdered roots of these three plants, powdered root of Derris brevipes variety coriacea and its ethanolic extract were screened for antifertility activity in proven fertile female rats at 200 and 600 mg/kg body weight, respectively and given orally on D(1-7) of pregnancy. Both doses of the root powder of Derris brevipes variety coriacea showed 50% anti-implantation activity and also a significant reduction in the number of litters born. The ethanolic extract exhibited 40% anti-implantation activity when given orally at 600 mg/kg body weight. The rats, which continued their pregnancy, did not deliver any litters after their full term. Hence, the combined antifertility (anti-implantation and abortifacient) activity of the ethanolic extract was 100%. The results suggest that the ethanolic extract possesses more abortifacient type effect than the anti-implantation activity. The ethanolic extract also exhibited weak estrogenic activity when given alone and tested in immature ovariectomised female albino rats. But, when given along with ethinyl estradiol, it exhibited slight antiestrogenic activity. Histological and biochemical estimations were carried out to confirm this.
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116
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Rajan S, Ramesh D. Photochemical oxidation of alcohols by iron(3+), copper(2+) and silver(1+) ions. J Org Chem 2002. [DOI: 10.1021/jo01315a031] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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117
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Abstract
The Nilgiri is a popular massif towering high in the Western Ghats in South India with an altitude of 2623 m. Nature has been magnanimous in bestowing Nilgiri district with rich evergreen temperate to tropical forests. A high degree of biodiversity, marked by varied flora and fauna of good therapeutic potential as well as the varied number of indigenous groups of people in this area, makes it very popular among herbalists. The district has six anthropologically well defined ethnic groups namely Todas, Kotas, Kurumbas, Irulas, Paniyas and Kattunayakas living here possibly since 1200 B.C. The present review highlights the ethnobiological profile of six indigenous populations and their dependence on ambient flora and fauna for traditional health care needs. It has been observed that about 2700 therapeutically potent plant species are available in this hill station of which almost all have come from local medicine. Some have been explored scientifically. However, about 150 plant species are still to be explored for their therapeutic potential. The ethnography, phytochemical and therapeutic uses as well as the anthropological perspectives of the local medicines have been discussed in this review.
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118
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Karschin C, Wischmeyer E, Preisig-Müller R, Rajan S, Derst C, Grzeschik KH, Daut J, Karschin A. Expression pattern in brain of TASK-1, TASK-3, and a tandem pore domain K(+) channel subunit, TASK-5, associated with the central auditory nervous system. Mol Cell Neurosci 2001; 18:632-48. [PMID: 11749039 DOI: 10.1006/mcne.2001.1045] [Citation(s) in RCA: 105] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
TWIK-related acid-sensitive K(+) (TASK) channels contribute to setting the resting potential of mammalian neurons and have recently been defined as molecular targets for extracellular protons and volatile anesthetics. We have isolated a novel member of this subfamily, hTASK-5, from a human genomic library and mapped it to chromosomal region 20q12-20q13. hTASK-5 did not functionally express in Xenopus oocytes, whereas chimeric TASK-5/TASK-3 constructs containing the region between M1 and M3 of TASK-3 produced K(+) selective currents. To better correlate TASK subunits with native K(+) currents in neurons the precise cellular distribution of all TASK family members was elucidated in rat brain. A comprehensive in situ hybridization analysis revealed that both TASK-1 and TASK-3 transcripts are most strongly expressed in many neurons likely to be cholinergic, serotonergic, or noradrenergic. In contrast, TASK-5 expression is found in olfactory bulb mitral cells and Purkinje cells, but predominantly associated with the central auditory pathway. Thus, TASK-5 K(+) channels, possibly in conjunction with auxiliary proteins, may play a role in the transmission of temporal information in the auditory system.
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119
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Rajan S, Liebman HA. Treatment of hepatitis C related thrombocytopenia with interferon alpha. Am J Hematol 2001; 68:202-9. [PMID: 11754404 DOI: 10.1002/ajh.1180] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Thrombocytopenia is a common extrahepatic manifestation of hepatitis C (HCV) infection. Treatment with steroids may be effective, but can exacerbate the viral infection. Interferon alpha (INF) has documented efficacy in the treatment of HCV, but its use in the treatment of HCV thrombocytopenia is controversial. We treated eight patients with HCV-related thrombocytopenia, who had platelet counts of fewer than 50 x 10(9)/l (range: 16 to 46 x 10(9)/L) with INF 3 MU SQ three times a week. Planned duration of treatment was 24 weeks. Five patients had no evidence of hepatic cirrhosis, three had cirrhosis, and two had palpable splenomegaly. Only three patients tolerated the full course of treatment, and all three had improvement in their platelet counts to greater than 50 x 10(9)/l. Two other patients had improvement in platelet counts to more than 50 x 10(9)/l with shorter duration of treatment (six and 16 weeks, respectively). The mean increase in platelet count in the five responders was 44 x 10(9)/lL (range: 28 to 90 x 10(9)/l). The average peak platelet count in the responders was 81 x 10(9)/l (range: 62 to 136 x 10(9)/l). Duration of response ranged from four to 18+ months, with the shortest responses observed in the two patients treated with a shorter course of INF. Response was independent of the presence of cirrhosis. Responding patients had improvement in hepatic transaminases, reduction in cryoglobulin and anticardiolipin antibodies, and HCV plasma RNA when tested. Relapse was associated with an increase in these laboratory markers of HCV infection. We conclude that INF can be an effective treatment in patients with HCV-related thrombocytopenia.
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Hosseinpour AR, Rajan S, Nashef SA. A technique to control bleeding from an inaccessible part of an aortic end-to-end anastomosis. Ann R Coll Surg Engl 2001; 83:383-5. [PMID: 11777130 PMCID: PMC2503692] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023] Open
Abstract
A simple technique is presented for the control of bleeding from the posterior aspect of an aortic end-to-end anastomosis.
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121
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Kumar K S, Venugopal M, Rajan S. Middle ear malignancy masquerading as csom. Indian J Otolaryngol Head Neck Surg 2001; 53:135-7. [PMID: 23119776 DOI: 10.1007/bf02991508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
Malignant transformation in middle ear cleft is an extremely rare phenomenon, squamous cell carcinoma being the most likely neoplasm. Classical hallmarks of otologic haemorrage, facial palsy and inner ear damage may not be evident in a few cases though a long history of CSOM provides accolade. We present a young male operated upon for a seemingly benign otologic supprative illness where an extensively destructive malignant disease with intracranial extension was unveiled.
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122
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Rajan S, Wischmeyer E, Karschin C, Preisig-Müller R, Grzeschik KH, Daut J, Karschin A, Derst C. THIK-1 and THIK-2, a novel subfamily of tandem pore domain K+ channels. J Biol Chem 2001; 276:7302-11. [PMID: 11060316 DOI: 10.1074/jbc.m008985200] [Citation(s) in RCA: 133] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Two cDNAs encoding novel K(+) channels, THIK-1 and THIK-2 (tandem pore domain halothane inhibited K(+) channel), were isolated from rat brain. The proteins of 405 and 430 amino acids were 58% identical to each other. Homology analysis showed that the novel channels form a separate subfamily among tandem pore domain K(+) channels. The genes of the human orthologs were identified as human genomic data base entries. They possess one intron each and were assigned to chromosomal region 14q24.1-14q24.3 (human (h) THIK-1) and 2p22-2p21 (hTHIK-2). In rat (r), THIK-1 (rTHIK-1) is expressed ubiquitously; rTHIK-2 expression was found in several tissues including brain and kidney. In situ hybridization of brain slices showed that rTHIK-2 is strongly expressed in most brain regions, whereas rTHIK-1 expression is more restricted. Heterologous expression of rTHIK-1 in Xenopus oocytes revealed a K(+) channel displaying weak inward rectification in symmetrical K(+) solution. The current was enhanced by arachidonic acid and inhibited by halothane. rTHIK-2 did not functionally express. Confocal microscopy of oocytes injected with green fluorescent protein-tagged rTHIK-1 or rTHIK-2 showed that both channel subunits are targeted to the outer membrane. However, coinjection of rTHIK-2 did not affect the currents induced by rTHIK-1, indicating that the two channel subunits do not form heteromers.
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MESH Headings
- Amino Acid Sequence
- Anesthetics, Inhalation/pharmacology
- Animals
- Anions
- Arachidonic Acid/pharmacology
- Base Sequence
- Brain/metabolism
- Chromosome Mapping
- Chromosomes, Human, Pair 14
- Chromosomes, Human, Pair 2
- Cloning, Molecular
- DNA, Complementary/metabolism
- Electrophysiology
- Gastric Mucosa/metabolism
- Green Fluorescent Proteins
- Halothane/pharmacology
- Humans
- Hydrogen-Ion Concentration
- In Situ Hybridization
- Introns
- Kidney/metabolism
- Liver/metabolism
- Luminescent Proteins/metabolism
- Microscopy, Confocal
- Molecular Sequence Data
- Phylogeny
- Potassium/metabolism
- Potassium Channels/biosynthesis
- Potassium Channels/chemistry
- Potassium Channels/genetics
- Potassium Channels, Tandem Pore Domain
- Rats
- Recombinant Proteins/metabolism
- Reverse Transcriptase Polymerase Chain Reaction
- Sequence Homology, Amino Acid
- Tissue Distribution
- Xenopus/metabolism
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Derst C, Karschin C, Wischmeyer E, Hirsch JR, Preisig-Müller R, Rajan S, Engel H, Grzeschik K, Daut J, Karschin A. Genetic and functional linkage of Kir5.1 and Kir2.1 channel subunits. FEBS Lett 2001; 491:305-11. [PMID: 11240146 DOI: 10.1016/s0014-5793(01)02202-5] [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: 11/25/2022]
Abstract
We have identified several cDNAs for the human Kir5.1 subunit of inwardly rectifying K(+) channels. Alternative splicing of exon 3 and the usage of two alternative polyadenylation sites contribute to cDNA diversity. The hKir5.1 gene KCNJ16 is assigned to chromosomal region 17q23.1-24.2, and is separated by only 34 kb from the hKir2.1 gene (KCNJ2). In the brain, Kir5.1 mRNA is restricted to the evolutionary older parts of the hindbrain, midbrain and diencephalon and overlaps with Kir2.1 in the superior/inferior colliculus and the pontine region. In the kidney Kir5.1 and Kir2.1 are colocalized in the proximal tubule. When expressed in Xenopus oocytes, Kir5.1 is efficiently targeted to the cell surface and forms electrically silent channels together with Kir2.1, thus negatively controlling Kir2.1 channel activity in native cells.
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Waidmann TA, Rajan S. Race and ethnic disparities in health care access and utilization: an examination of state variation. Med Care Res Rev 2001; 57 Suppl 1:55-84. [PMID: 11092158 DOI: 10.1177/1077558700057001s04] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Health disparities among racial and ethnic groups have a long history and continue to exist in the United States. The U.S. government has established as a goal for the year 2010 the elimination of racial/ethnic health differences in six areas. This article examines disparities in one of those areas: access to high-quality health care. Several measures of access to and use of health care services are studied both nationally and in 13 diverse states. The authors find that both the magnitude of racial and ethnic disparity and the reasons behind it depend significantly on the state, the ethnic group, and the type of outcome measure being studied. Such information can be valuable for state and national policy makers in targeting resources and in designing effective strategies for the elimination of racial and ethnic disparities.
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125
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Rajan S, Zuckerman S, Brennan N. Confirming insurance coverage in a telephone survey: evidence from the National Survey of America's families. INQUIRY : A JOURNAL OF MEDICAL CARE ORGANIZATION, PROVISION AND FINANCING 2001; 37:317-27. [PMID: 11111288] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
Until recently, most surveys of insurance coverage have classified people as uninsured if they have not been assigned some coverage in response to one of a series of questions about specific types of insurance. This "residual" approach to measuring uninsurance rates has not required respondents to either verify their insurance status or confirm that they are uninsured. Using the 1997 National Survey of America's Families, this paper examines the impact of a question confirming whether individuals for whom no insurance coverage is reported are, in fact, uninsured. The results of our analysis suggest that a confirmation question as part of a telephone-based survey works to lower estimates of the uninsured.
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