376
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Chakrabarti S, Komatireddy S, Mandal AK, Balasubramanian D. Gene symbol: CYP1B1. Disease: glaucoma, primary congenital. Hum Genet 2003; 113:556. [PMID: 14640114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/27/2023]
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377
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Chakrabarti S, Keeton BR, Salmon AP, Vettukattil JJ. Acquired combined immunodeficiency associated with protein losing enteropathy complicating Fontan operation. Heart 2003; 89:1130-1. [PMID: 12975395 PMCID: PMC1767867 DOI: 10.1136/heart.89.10.1130] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
It is vitally important that the immunological aspect of protein losing enteropathy following Fontan procedures is highlighted, in order to decrease significant morbidity and mortality
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378
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Dharmaraj N, Reddy A, Kiran V, Mandal A, Panicker S, Chakrabarti S. PAX6 gene mutations and genotype-phenotype correlations in sporadic cases of aniridia from India. Ophthalmic Genet 2003; 24:161-5. [PMID: 12868034 DOI: 10.1076/opge.24.3.161.15607] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
In order to understand the underlying molecular genetic defect causing aniridia in India, eight probands from sporadic cases were screened for all 14 exons of the PAX6 gene using polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP). Direct sequencing of the SSCP variants revealed a nonsense mutation (R317X) in the eleventh exon leading to a premature termination of the PAX6 protein in the proline-serine-threonine (PST)-rich domain in two probands. Another proband exhibited an intronic polymorphism (IVS 9-12 C-T). The mutation resulted in loss of function of the PAX6 protein along with variable phenotypic manifestations in the probands. This is the first report describing a PAX6 gene mutation in aniridia cases from India and highlights the variable expressivity in phenotypes due to haploinsufficiency.
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379
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Chakrabarti S, Tsao S, Vettukattil JJ, Gnanapragasam JP. Pulmonary vein stenosis mimicking chronic lung disease. Acta Paediatr 2003; 92:857-8. [PMID: 12892169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 03/04/2023]
Abstract
UNLABELLED The presence of recurrent respiratory symptoms and right heart enlargement in an ex-premature infant is suggestive of chronic lung disease. Pulmonary vein stenosis is a rare, progressive disorder that produces similar symptoms and signs. A case is reported in which pulmonary vein stenosis was revealed by Doppler echocardiography, and this application is recommended in similar cases. Pulmonary vein stenosis is an extremely rare and progressive disorder, which, if left untreated, is usually fatal. The possibility of this diagnosis may not be considered during clinical examination and may be overlooked during routine echocardiography. CONCLUSION This report describes a patient with pulmonary vein stenosis in whom the diagnosis was delayed as she had symptoms and signs more commonly associated with chronic lung disease.
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380
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Chakrabarti S, Brown J, Guttridge M, Pamphilon DH, Lankester A, Marks DI. Early lymphocyte recovery is an important determinant of outcome following allogeneic transplantation with CD34+ selected graft and limited T-cell addback. Bone Marrow Transplant 2003; 32:23-30. [PMID: 12815474 DOI: 10.1038/sj.bmt.1704082] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
We evaluated the outcome of 29 patients (age 22-60 years), who received a CD34+selected related (n=16) or unrelated graft (n=13) with limited T-cell addback (TCAB) (median 5.9 x 10(4)/kg) following full-intensity conditioning for haematological malignancies. In all, 16 patients (55%) had either advanced disease or previous transplants. The cumulative incidences of grade 2-4 acute GVHD were 15.4 and 19.2% and that for chronic extensive GVHD were 35 and 37% in related and unrelated graft recipients, respectively. The strongest predictor of nonrelapse mortality and overall survival was the absolute lymphocyte count (ALC) at 30 days; patients with ALC<0.35 x 10(9)/l having an NRM and OS of 59.2 and 24.7%, compared to 10 and 90% in those with a higher ALC. Patients with acute leukaemia had poorer survival and this was associated with a lower ALC as well. Thus, TCAB with a CD34+ selected graft resulted in a comparable outcome in both older and younger patients, but the survival was strongly influenced by early lymphocyte recovery.
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381
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Jhirwal OP, Chakrabarti S. Somatoform pain disorder: a valid diagnosis? Acta Psychiatr Scand 2003. [PMID: 12807381 DOI: 10.1034/j.1600-0447.2003.00160.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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382
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Abstract
Although dilated coronary arteries are uncommon in children, three cases are presented which, even more unusually, were not associated with Kawasaki's disease
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383
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Chakrabarti S, Osman H, Collingham K, Milligan DW. Polyoma viruria following T-cell-depleted allogeneic transplants using Campath-1H: incidence and outcome in relation to graft manipulation, donor type and conditioning. Bone Marrow Transplant 2003; 31:379-86. [PMID: 12634729 DOI: 10.1038/sj.bmt.1703847] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Haemorrhagic cystitis (HC) is an important cause of morbidity following stem cell transplantation (SCT) and has been associated with polyoma virus infection. We studied the incidence and outcome of polyoma virus infection in 58 T-cell-depleted SCT patients. T-cell depletion was carried out using Campath-1H, either 10 or 20 mg in vitro (n=33) or 50 or 100 mg in vivo (n=25) following conventional (n=35) or nonmyeloablative conditioning (n=23). A total of 21 patients (36%) had polyoma viruria at a median of 35 days (5-114); 30% among patients receiving Campath in vitro and 44% among those given in vivo. The only risk factor for polyoma viruria was graft-versus-host disease GVHD grade >or=2. The onset of polyoma viruria coincided with Cytomegalovirus (CMV) reactivation in all six patients who reactivated both viruses. Prolonged viruria (defined as polyoma viruria >2 weeks) was documented in 10 patients (17%) and this was associated with GVHD >or=grade 2. HC occurred in four patients. Prolonged viruria was associated with HC only in patients receiving unrelated donor grafts following conventional conditioning. HC was not observed following nonmyeloablative conditioning despite a higher incidence of prolonged viruria. Thus, HC was uncommon in patients with polyoma viruria following T-cell depletion with Campath, particularly after reduced intensity conditioning.
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384
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Komatireddy S, Chakrabarti S, Mandal AK, Reddy ABM, Sampath S, Panicker SG, Balasubramanian D. Mutation spectrum of FOXC1 and clinical genetic heterogeneity of Axenfeld-Rieger anomaly in India. Mol Vis 2003; 9:43-8. [PMID: 12592227] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/01/2023] Open
Abstract
PURPOSE Axenfeld-Rieger anomaly (ARA) is a form of anterior segment dysgenesis of the eye, mainly caused by mutations in the FOXC1 gene. We had earlier reported a novel mutation in the wing region of FOXC1 in an autosomal dominant family. The present study was aimed to identify the spectrum of mutations in the FOXC1 gene in a cohort of Indian ARA patients from different ethnic backgrounds, and to understand its role in the disease pathogenesis. METHODS Two new autosomal dominant families and seven sporadic cases of ARA from different ethnic backgrounds were screened for mutations by direct sequencing of the coding region of the FOXC1 gene. Another autosomal dominant ARA family that was previously reported by us was also included for comparative analysis of clinical genetic parameters. The segregation of the mutations in the autosomal dominant families was analyzed by haplotype and restriction analysis. Genotype-phenotype correlation were also undertaken to study the role of FOXC1 in phenotypic manifestation in the patient cohort. RESULTS Three of the nine ARA cases harbored mutations in FOXC1, of which two novel nonsense mutations Q2X and Q123X, resulted in haploinsufficiency of the gene product. The missense mutation (M161K) that we previously reported in an autosomal dominant family was also found in another family. Haplotype analysis of these two families suggested multiple founders in the same ethnic group. The mutations resulted in variable expressions of phenotype among the patients as assessed from their prognosis based on visual outcomes. CONCLUSIONS Significant genetic heterogeneity of FOXC1 was observed in a multi-ethnic population studied in this region of India resulting in variable ARA phenotypes. The different visual outcome seen in the patients suggest a variable expression of FOXC1 and also provide some insight for understanding the gene functions in this population.
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385
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Cane PA, van den Hoogen BG, Chakrabarti S, Fegan CD, Osterhaus ADME. Human metapneumovirus in a haematopoietic stem cell transplant recipient with fatal lower respiratory tract disease. Bone Marrow Transplant 2003; 31:309-10. [PMID: 12621469 DOI: 10.1038/sj.bmt.1703849] [Citation(s) in RCA: 115] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Respiratory viruses are increasingly recognized as a cause of pneumonitis following haematopoietic stem cell transplantation (HSCT). However, frequently, no pathogen is identified in cases of suspected viral pneumonia. Recently, a previously undescribed paramyxovirus, designated 'human metapneumovirus' (hMPV), was isolated from children with respiratory illness. We have detected hMPV as the sole pathogen in the nasopharyngeal aspirate of an HSCT recipient who succumbed to progressive respiratory failure following an upper respiratory prodrome. This report highlights the importance of further studies to elucidate the role of hMPV in causing respiratory illnesses in the HSCT population.
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386
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Chakrabarti S. Non-herpes virus infections after stem cell transplantation and anti-viral immunity. Transplant Proc 2003; 35:509-10. [PMID: 12591508 DOI: 10.1016/s0041-1345(02)03871-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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387
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Chakrabarti S, Mackinnon S. The relevance of nonmyeloablative transplants in developing countries: lessons from the UK experience. Transplant Proc 2003; 35:172-3. [PMID: 12591353 DOI: 10.1016/s0041-1345(02)03870-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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388
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Chakrabarti S, Reddy A, Duncan A. The use of the vacuum extractor at Northampton General Hospital: a review and critique. J OBSTET GYNAECOL 2003. [DOI: 10.1080/718591760] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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389
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Ragothaman M, Sarangmath N, Chaudhary S, Khare V, Mittal U, Sharma S, Komatireddy S, Chakrabarti S, Mukerji M, Juyal RC, Thelma BK, Muthane UB. Complex phenotypes in an Indian family with homozygous SCA2 mutations. Ann Neurol 2003; 55:130-3. [PMID: 14705123 DOI: 10.1002/ana.10815] [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: 11/08/2022]
Abstract
We describe a consanguineous Indian family having spinocerebellar ataxia type 2 (SCA2) expansions with complex phenotypes (early-onset, dopa-responsive parkinsonism, ataxia and retinitis pigmentosa). The two probands having homozygous SCA2 mutations presenting with early-onset dopa-responsive parkinsonism without ataxia develop dyskinesias within a year of starting levodopa. Their siblings, heterozygous for SCA2 mutations, had retinitis pigmentosa with or without ataxia. Approximately 38% of family members with SCA2 mutations were asymptomatic.
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390
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Kottaridis PD, Milligan DW, Chopra R, Chakraverty RK, Chakrabarti S, Robinson S, Peggs K, Verfuerth S, Pettengell R, Marsh JC, Schey S, Mahendra P, Morgan GJ, Hale G, Waldmann H, Ruiz de Elvira MC, Williams CD, Devereux S, Linch DC, Goldstone AH, MacKinnon S. In vivo CAMPATH-1H prevents GvHD following nonmyeloablative stem-cell transplantation. Cytotherapy 2002; 3:197-201. [PMID: 12171726 DOI: 10.1080/146532401753174025] [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: 10/27/2022]
Abstract
BACKGROUND We have investigated a novel nonmyeloablative conditioning regimen in 44 patients with hematological malignancies. The median patient age was 41 years. Many of the patients had high-risk features, including 19 patients with a previous failed transplant. METHODS Recipient conditioning consisted of CAMPATH-1H 20 mg/day on Days -8 to -4, fludarabine 30 mg/m(2) on Days -7 to -3 and melphalan 140 mg/m(2) on Day -2. Thirty-six recipients received unmanipulated G-CSF mobilized PBSC from HLA identical siblings and eight received unmanipulated BM from MUD. GvHD prophylaxis was with CYA alone for 38 patients and CYA plus MTX for six sibling recipients. RESULTS Forty-two of the 43 evaluable patients had sustained engraftment. Results of chimerism analysis using microsatellite PCR indicate that 18 of 31 patients studied were full donor chimeras, while the other patients were mixed chimeras in one or more lineages. At a median follow-up of 9 months (range, 3-29 months) 33 patients remain alive in CR, or with no evidence of disease progression. Seven patients relapsed or progressed post-transplant and four of them subsequently died. Four patients died from regimen-related complications. There were no cases of Grades III-IV acute GvHD. Only two patients developed Grade II acute GvHD and only one had chronic GvHD. The estimated probability of non-relapse mortality at 1 year was 11%.Results: Although longer follow-up is needed to establish the long-term remission rates, this study demonstrates that this nonmyeloablative preparative regimen is associated with durable engraftment, minimal toxicity and low incidence of GvHD.
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MESH Headings
- Adolescent
- Adult
- Alemtuzumab
- Antibodies, Monoclonal/immunology
- Antibodies, Monoclonal/therapeutic use
- Antibodies, Monoclonal, Humanized
- Antibodies, Neoplasm/immunology
- Antibodies, Neoplasm/therapeutic use
- Antineoplastic Agents, Alkylating/therapeutic use
- Drug Therapy, Combination
- Female
- Graft Survival/drug effects
- Graft Survival/immunology
- Graft vs Host Disease/drug therapy
- Graft vs Host Disease/immunology
- Graft vs Host Disease/prevention & control
- Hematologic Neoplasms/immunology
- Hematologic Neoplasms/physiopathology
- Hematologic Neoplasms/therapy
- Humans
- Immunosuppression Therapy/methods
- Immunosuppression Therapy/trends
- Immunosuppressive Agents/therapeutic use
- Male
- Melphalan/therapeutic use
- Middle Aged
- Recurrence
- Stem Cell Transplantation/adverse effects
- Stem Cell Transplantation/methods
- Survival Rate
- Transplantation Chimera/immunology
- Transplantation Conditioning/methods
- Transplantation Conditioning/trends
- Transplantation, Homologous/adverse effects
- Transplantation, Homologous/methods
- Treatment Outcome
- Vidarabine/analogs & derivatives
- Vidarabine/therapeutic use
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391
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392
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Kaur I, Roy S, Chakrabarti S, Sarhadi VK, Majumder PP, Bhanwer AJS, Singh JR. Genomic diversities and affinities among four endogamous groups of Punjab (India) based on autosomal and mitochondrial DNA polymorphisms. Hum Biol 2002; 74:819-36. [PMID: 12617491 DOI: 10.1353/hub.2003.0007] [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: 11/11/2022]
Abstract
Nineteen insertion/deletion and restriction site polymorphisms on autosomal and mitochondrial genomes and mitochondrial DNA hypervariable segment 1 sequences were used to study genetic diversities and affinities among four endogamous groups of Punjab, India. High values of heterozygosity were noted in all four groups, both in the autosomal and mitochondrial genomes. The coefficient of gene differentiation among the groups, however, was found to be low. Genetic distance and phylogenetic analyses based on these data indicated that inferences on affinities among the populations were different when the two sets of loci (autosomal and mitochondrial) were considered separately. We have interpreted these results on the basis of some known historical data on migrations into this region. The results of this study when compared with the findings of some previous studies indicate that there are regional differences in the patterns of correlation between genomic and sociocultural affinities within India.
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393
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Chakrabarti S, Chand PK. Lithium - induced tardive dystonia. Neurol India 2002; 50:473-5. [PMID: 12577099 DOI: pmid/12577099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Tardive dystonia is an uncommon form of chronic dystonia, which usually develops on exposure to neuroleptics. Tardive dystonia (Tdt) following lithium therapy has not been previously reported. The case of 38 year old man with bipolar affective disorder who developed tardive dystonia while on maintenance lithium treatment is described. Presentation of Tdt in this patient was fairly characteristic although there was no suggestion of recent neuroleptic exposure. Tdt known to have poor treatment response, responded very well to clozapine, a novel anti-psychotic, in this case. To conclude, Tdt may develop on exposure to drugs other than neuroleptics. An adequate trial to clozapine can prove to be a useful treatment option.
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394
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Chakrabarti S, Chen S, Evans T, Karmazyn M. Endothelins in the microvasculature and heart in diabetes. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2002; 498:97-108. [PMID: 11900407 DOI: 10.1007/978-1-4615-1321-6_13] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
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395
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Chakrabarti S, Garvie D, RayChaudhuri K, Rao GG. Rationalizing the use of polymerase chain reaction based tests for diagnosis of common viral infections of the central nervous system. J Clin Pathol 2002; 55:560. [PMID: 12101216 PMCID: PMC1769697 DOI: 10.1136/jcp.55.7.560] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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396
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397
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Rymes NL, Lester W, Connor C, Chakrabarti S, Fegan CD. Outpatient management of DVT using low molecular weight heparin and a hospital outreach service. CLINICAL AND LABORATORY HAEMATOLOGY 2002; 24:165-70. [PMID: 12067281 DOI: 10.1046/j.1365-2257.2002.00440.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
In recent years there have been several studies comparing the efficacy and safety of low molecular weight (LMW) and unfractionated heparin for the treatment of deep venous thrombosis (DVT), showing them in the clinical trial setting to be equal in these regards. LMWH has the advantage of once daily subcutaneous injection and daily monitoring of levels is not usually required. This has led many centres to develop outpatient treatment strategies for these patients but evidence for the safety of this approach is scarce. In 1997 we developed a hospital outreach service for the treatment of patients with DVT and, in a retrospective study, have compared the outcome in 172 patients treated at home with 172 age, sex and thrombotic risk factor matched inpatients treated at our institution with unfractionated heparin. Five patients in the home treatment group suffered a haemorrhagic event, compared with six patients in the hospital group. One patient in the home treatment group had a recurrent DVT within the first 3 months of treatment; in the hospital-treated group, six patients had recurrent DVTs and nine developed pulmonary emboli. At 3 months, there were three deaths in the home treatment group, compared with five deaths in the hospital group. There was no difference in re-admission rate at 3 months: 23 in the home treatment group, 24 in the hospital-treated group. Average length of hospital stay for the home-treatment group was 2.1 days and 12 days for the hospital group. Warfarin control was found to be significantly better in those patients treated at home, and only 18% of patients treated in hospital received heparin according to hospital guidelines. In conclusion, outpatient management of patients with DVT using LMWH is as safe as hospitalization and continuous infusion of unfractionated heparin. The complication rate was lower in the home treatment group and, in particular, the incidence of recurrent thrombosis was significantly less in the home treatment group. In addition, warfarin control was better when managed by specialist nurses. Patients expressed a preference for home treatment.
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398
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Malhotra S, Chakrabarti S, Nehra A. Psychological intervention with parents of autistic children. Indian J Psychiatry 2002; 44:108-17. [PMID: 21206555 PMCID: PMC2954337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
An important component of management of autism is the role played by parents as active collaborators in the process. The case histories of 5 children with autism are described in this report. Psychological intervention carried out with parents of these children is detailed. The treatment package included a mix of behavioural, supportive and educational techniques, delivered in 3-6 sessions of 45- 60 minute each, in the setting of a child psychiatric clinic. Results showed that on the whole parents found this brief contact helpful. They rated emotional aspects of the support offered to be the most helpful. Child psychiatric clinics are often the first point of contact for parents with autistic children, and may have an important, primarily supportive role to play at this early stage of treatment.
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399
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Chakrabarti S, Bhattacharyya D, Dasgupta D. Structural basis of DNA recognition by anticancer antibiotics, chromomycin A(3), and mithramycin: roles of minor groove width and ligand flexibility. Biopolymers 2002; 56:85-95. [PMID: 11592055 DOI: 10.1002/1097-0282(2000)56:2<85::aid-bip1054>3.0.co;2-7] [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: 11/09/2022]
Abstract
Anticancer antibiotics, chromomycin A(3) (CHR) and mithramycin (MTR), inhibit cellular processes like transcription and replication, by binding reversibly to double-stranded DNA via minor groove, in the presence of bivalent metal ions like Mg(2+) with GC base specificity. Here, we have attempted to assess the roles of two parameters-namely DNA groove dimension and flexibility of the ligand-in the structural recognition between the ligands, (drug)(2)Mg(2+) and DNA. For the purpose we have employed three synthetic oligonucleotides with minor groove width lying between B- and A-type structures as model DNA sequences: d(GCGCGCGC)(2) in B-form, d(CCGGCGCCGG)(2) in B-form with unusual wide minor groove, and (GGGGCCCC)(2) in A-form. Association of the (drug)(2)Mg(2+) with the oligomers have been probed using spectroscopic techniques like absorbance, fluorescence, and CD. The binding and thermodynamic parameters for the different association processes have also been characterized. Major conclusions from the above studies are as follows. Groove size of the oligomers influences the conformation of the bound ligand. A saccharide dependent variation in structural rigidity of the ligands, (MTR)(2)Mg(2+) and (CHR)(2)Mg(2+), has been observed that leads to differences in the energetics of recognition of the same DNA sequence by the two ligands. In contrast to (CHR)(2)Mg(2+), higher flexibility in (MTR)(2)Mg(2+) makes its conformation in the DNA bound form less sensitive to the groove dimension of DNA.
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400
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Khetawat D, Dutta P, Gupta S, Chakrabarti S. Emergence of rotavirus G4P8 strain among children suffering from watery diarrhea in Calcutta, India. Intervirology 2002; 44:306-10. [PMID: 11684892 DOI: 10.1159/000050062] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Rotavirus RNAs from the fecal samples were hybridized with cDNAs specific for G1 and G2 genotypes. 59 out of 138 samples (42.7%) did not hybridize with either probe. The cDNAs coding for VP7 and VP4 from one such sample, SC134, were synthesized by combined reverse transcriptase/polymerase chain reaction (PCR) using specific oligonucleotide primers and were used as probes to screen those local isolates which did not hybridize with either G1 or G2. 26/59 (44%) of fecal RNA hybridized with these cDNAs indicating a possible emergence of this strain in this part of India. The VP7 and VP4 genotype specificity of SC134 was found to be G4P8 by multiplex PCR. The VP7 gene of SC134 was cloned and characterized in detail by restriction enzyme digestion and DNA sequence analysis. Comparison of nucleotide and predicted amino acid sequence of the VP7 gene of SC134 with other serotypes revealed that the VP7 gene of SC134 was closely related to G4. However, amio acids within the VP7 sequence differed in seven positions with that of both the subtype 'A' and 'B' of the G4 serotype. To establish the relation of this emerging strain with the other reported G4 strains, a phylogenetic tree was constructed and SC134 was found to be more closely related to the ST3 strain isolated in England and included in the tetravalent vaccine formulation along with two Japanese strains, although all four were distinct and did not form any cluster as was evident by the horizontal distance separating them. The VP7 gene sequence of SC134 was submitted to EMBL and was assigned the accession number AJ278217.
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