Search PubMed⌕ Search

Biomedical subjects

D Mohanty

Publications and source records attributed to D Mohanty.

At least 19 recordsLinked to original sources
PubMed2006

Flow cytometric quantification of antigen D sites on red blood cells of partial D and weak D variants in India.

The D antigenic sites are diminished in weak D and partial D variants. The aim of this study was to estimate D antigen on RBC in weak D and partial D variants in Indian population by using flow cytometric method. Blood samples of 42 cases of partial D, eight cases of weak D and 123 normal Rh phenotypes identified by serological methods were used in the study. An indirect immunofluorescence method was employed using 29 monoclonal anti-D as primary antibody. The D antigenic sites were calculated using control RBC as internal standard. The D antigenic sites in weak D and partial D variants are less than that found in normal Rh phenotypes. In weak D, the D antigenic sites were between 1500 and 7000 D antigens per cell. Among partial D variants, DVI had minimum and DVa had maximum number of D sites. Flow cytometry is a very good tool for demonstrating minor variation in D antigen when serological methods are inconclusive. The D antigenic sites per RBC in partial D variants identified in Indian population are reported for the first time.

Antibodies, Monoclonal↗
PubMed2006

Production of murine monoclonal anti-B.

BACKGROUND & OBJECTIVE: Monoclonal antibodies against red blood cell antigens used in research and as diagnostics in India are commercially procured from western countries. Indigenously generated potent clones are not available in India. Hence, the objective of the present study was to raise potent murine monoclonal antibodies against A, B and H blood group antigens indigenously and establish a stable clone of anti-B secreting cells. METHODS: Spleen cells of female BALB/c mice immunized with B group red blood cells were fused in presence of polyethylene glycol (PEG) 1500 with a mouse myeloma cell line Sp 2/0 Ag. 14 in hypoxanthine aminopterine thymidine (HAT) selective medium and incubated at 37 degrees C, 5 per cent CO(2) and 95 per cent humidity for a week. RESULTS: The culture supernatant of the wells showing anti-B activity, were further subcloned and a clone 2C4D5F10 was generated which showed a good potency, avidity and specificity. INTERPRETATION & CONCLUSION: The anti-B clones thus produced indigenously provided a useful reagent in blood group typing. The unlimited availability unlike polyclonal antisera makes this reagent more cost-effective. It also ensures a regular supply with the similar specificity.

ABO Blood-Group System↗
PubMed2005

Three novel polymorphisms in the beta globin gene.

We report on three novel polymorphisms in and around the beta globin gene. Two of them are intronic (IVS2) polymorphisms (IVS 2 nt 200-203 (-CTTT) and IVS2 82-83 (-AG)). The third is a novel G-->C substitution at nt +1707 related to the beta globin cap site. This +1707 G-->C polymorphism was detected in 23.5% of chromosomes among 140 samples from India. It seems to be a novel but common polymorphism among Indians. There was no linkage between these novel polymorphisms and any beta thalassemia mutation.

Adult↗
PubMed2005

Evaluation of markers of endothelial damage in cases of young myocardial infarction.

The pathogenesis of arterial thrombotic disease involves multiple genetic and environmental factors related to atherosclerosis and thrombosis. The endothelium is a monolayer of polygonal cells that extend continuously over the luminal surface of the entire vasculature. Injury to the endothelium leads to dysfunction. The causes of injury include lipids, immune complexes, microorganisms, smoking, hypertension, aging, diabetes mellitus and trauma. Studies have been done to evaluate the role of different adhesion molecules on the endothelial membrane in the pathogenesis of atherosclerosis. These molecules are intercellular adhesion molecule type-1 (ICAM-1), vascular cell adhesion molecule type-1 (VCAM-1), platelet/endothelial cell adhesion molecule-1 (PECAM-1), soluble P-selectin (sP-selectin) and soluble E-selectin (sE-selectin). One-hundred and twenty patients of myocardial infarction (age below 40 years) were recruited from the out-patients department of Department of Cardiology, KEM Hospital, Mumbai. All the patients were recruited 8-10 weeks after stabilization after MI. We estimated the levels of sP-selectin, sE-selectin, sPECAM-1 and serum homocysteine. Healthy age and sex-matched controls and family controls were also recruited in the present study. The levels of sP-selectin, sE-selectin and sPECAM-1 did not differ significantly in cases as compared to controls (p>0.05). Hyperhomocysteinemia was significantly associated with MI in comparison with controls (p<0.001) with an odds ratio of 6.26 (95% confidence limits 3.11-12.76). Folic acid was able to correct hyperhomocysteinemia in a large majority of the cases. Although the levels of sP-selectin, sE-selectin and sPECAM-1 decreased after folic acid therapy, it was only sE-selectin which was significantly reduced (p<0.05). Thus, folic acid had a dual effect in that it reduced hyperhomocysteinemia and sE-selectin which showed a significant reduction on folate supplementation for 15 days.

Adult↗
PubMed2005

Immunogenetic association in patients with antineutrophil cytoplasmic antibodies (ANCA) from Mumbai, Maharashtra, India.

Considerable genetic evidence exit for ANCA-associated vasculitis and pathogenesis. HLA A and B alleles identified serologically from 84 ANCA-positive patients were compared with 101 controls. Further subtyping were done in the 27 "pauci-immune" vasculitis patients using the polymerase chain reaction based PCR-SSOP technique and compared with controls (67). The results revealed that HLA A1 (OR=4.00; p value 2.72E-05), B17 (OR=3.38; p value 0.0008) and HLA B40 (OR=2.74; p value 0.001) were significantly increased among ANCA-positive patients when compared with the controls. Further, the molecular subtypes A*0101 (OR=5.04; p value 0.0005), B*5801 (OR=4.47; p value 0.0002) and haplotype A*0101-B*5801 (OR=4.47; p value 0.0001) were significantly increased among the autoimmune patients. The study revealed that HLA A1, B17 and B40 alleles are associated in production of antineutrophil autoantibodies and A*0101-B*5801 haplotype is significantly associated with autoimmune diseases and they may be invariably involved in disease pathogenesis in India.

Antibodies, Antineutrophil Cytoplasmic↗
PubMed2005

Co-existence of Bernard Soulier syndrome and factor XI deficiency in a family: a unified pathology?

Bernard Soulier syndrome (BSS) is an autosomal recessive disorder of platelet function. Factor XI deficiency leads to a variable bleeding tendency and the defect is also inherited in an autosomal recessive manner. In this paper we describe a case of BSS with severe deficiency of factor XI. The patient had both BSS and factor XI deficiency. The sister and both the parents were heterozygous for BSS and had factor XI deficiency. The brother is normal for both BSS and factor XI levels. Apart from the patient, no other family members had any history of bleeding in spite of having a deficiency of factor XI, which suggests that low level of factor XI in this family was not responsible for bleeding. Curiously, although the index patient inherited both Bernard Soulier syndrome and factor XI deficiency (FXI: C = 1.3%), he had mild bleeding symptoms restricted only to ecchymoses and petechiae. Detailed review of the pedigree showed that all the members who inherited the BSS phenotype, also inherited abnormal factor XI gene. Karyotype of the affected members of the family using standard Giemsa banding technique showed a normal picture. Considering the fact that the genes causing both BSS and factor XI are both on widely different chromosomes, their coinheritance in four members of the family without any unusual translocation suggest a unified pathology probably on the basis of a common transcription factor defect or a common post translational processing defect. This is the first case of coinheritance of BSS and factor XI deficiency reported in the English literature.

Bernard-Soulier Syndrome↗
PubMed2005

Frequency distribution of human platelet antigens in the Indian population.

This study was undertaken with an aim of establishing the frequency distribution of various human platelet antigens (HPA) in Indian populations by means of DNA-based technology. A total of 1164 people belonging to various population groups were studied for the frequency distribution of HPA. DNA extraction was performed from peripheral venous blood samples. Polymerase chain reaction allele-specific amplification technique was used for HPA genotyping. The HPA bands were visualized by using ethidium bromide-stained agarose gel, after electrophoresis. The homozygosity of the HPA-1b/1b genotype was found to be significantly higher (P < 0.05) in the Parsi population group and Vatalia Prajapati population group, compared to Maharashtrians. Frequency distribution of HPA-1b in our populations was found to be slightly lower than that reported in some western populations. This study has established a DNA technique to diagnose cases of NAITP definitively and to treat these cases during the neonatal period, and also gives the frequency distribution of HPA in some of the Indian population.

Antigens, Human Platelet↗
PubMed2005

Intracranial haemorrhage in severe haemophilia: prevalence and outcome in a developing country.

Intracranial haemorrhage (ICH) is a common cause of morbidity and mortality in haemophilic patients all over the world. From 1995 to 2004, we have investigated 37 patients with 43 episodes of ICH at our Comprehensive Haemophilia Care Center from a total of 600 registered patients. Diagnosis of ICH in the patients was confirmed by clinical, haematological and computed tomographic imaging data. Three patients died despite replacement therapy while one child who had a ventriculo-atrial shunt for acute hydrocephalus also died before further intervention. One of the four patients who died also had severe aplastic anaemia for 6 years in addition to severe haemophilia. Detailed history obtained from 143 families with haemophilia attending the Genetic Diagnosis Clinic at our Center showed a positive history of cerebral bleed in 39 episodes in 37 patients. Sixteen families gave a history of death in the family of haemophilic patients due to ICH, while in the remaining 21 families, the patients had survived the episode after treatment elsewhere. However, the ICH was not confirmed by image data in these cases. The treatment protocols were also not available in these cases. Conservative factor replacement therapy 100% correction for 3 days followed by 50-60% correction for 7 days) coupled with the epsilon amino caproic acid, the antifibrinolytic agent at least for 30 days led to a mortality (10.8%) similar to that of the western countries and almost no morbidity. Surgery was not required in any of these patients except in one elderly patient with HIV infection on antiretroviral therapy.

Adolescent↗
PubMed2005

The Duffy blood groups of Jarawas - the primitive and vanishing tribe of Andaman and Nicobar Islands of India.

Andaman and Nicobar Islands, union territory of India were inhabited by 14 aboriginal tribes. Some of these tribal populations have already become extinct, and the numbers of the existing ones are also dwindling. This group of islands being highly endemic for malaria, it was considered worthwhile to study the hunter-gatherer primitive tribe, Jarawas, for their Duffy blood group phenotype. Jarawas, the primitive tribe of Andaman Islands, inhabit the three jungle areas of South and one jungle area of Middle Andaman. Blood samples of 116 Jarawas were collected and tested for Duffy blood group and malarial parasite infectivity. The Duffy blood grouping was performed as per standard serological techniques, and peripheral smears were screened for malarial parasite and if present parasite density count was performed and the species identified. The results showed a total absence of both Fy(a) and Fy(b) antigens in two areas (Kadamtala and R.K. Nallah) and low prevalence of Fy(a) antigen in another two areas (Jirkatang and Tirur). There was absence of malarial parasite Plasmodium vivax infection though Plasmodium falciparum infection was present in 27.59% of cases. A very high frequency of Fy (a-b-) in the Jarawa tribe from all the four jungle areas of Andaman Islands along with total absence of P. vivax infections suggests the selective advantage offered to Fy (a-b-) individuals against P vivax infection.

Duffy Blood-Group System↗
PubMed2005

Mutations in GPIIIa molecule as a cause for Glanzmann thrombasthenia in Indian patients.

BACKGROUND: Glanzmann thrombasthenia (GT) results from a quantitative or qualitative defect of GPIIb-IIIa complex, the fibrinogen receptor on platelets, which plays a very important role in platelet aggregation. In this report we describe the molecular studies on 22 patients with Glanzmann Thrombasthenia at our institute. OBJECTIVES: The main objective was to identify the mutations present in our GT population in order to establish a strategy for genetic counseling and antenatal diagnosis. METHODS: Twenty-two patients with GT were included in the present study. Complete blood count (CBC), platelet aggregation, flow cytometry, Western blot, single strand conformation polymorphism (SSCP) and denaturing gradient gel electrophoresis (DGGE) were performed in all the patients. The patients showing an abnormal migration pattern in SSCP or DGGE were sequenced further on an automated sequencer. RESULTS: Of the 22 patients studied, mutations were detected in 12 individuals. Of these, 11 were novel mutations and one mutation Y115C was reported earlier. Flow cytometric analysis showed the absence of receptors in type I GT, highly reduced levels in type II GT and normal levels in type III GT. The DGGE analysis and SSCP analysis of the patients showed different migration patterns. Sequencing was performed in all patients showing an abnormal migration pattern. Of the 22 cases studied mutations could be detected in 12 cases of GT. We could detect six patients with point mutations, four patients with insertions and five patients with deletion mutations. Exon 4 has been found to be the most common site for mutations in our patients. CONCLUSION: This study has shown a wide array of mutations present in our GT patients which would be extremely useful in genetic counseling and prenatal diagnosis, essential in preventing these disorders in succeeding generations.

DNA Mutational Analysis↗
PubMed2005

Molecular diversity of HLA-Cw alleles in the Maratha community of Mumbai, Maharashtra, western India.

Recent advances suggest a significant role for the HLA-C locus as a target of alloreactions after bone marrow transplantation. The biological importance of products of the HLA-C locus, both as transplant antigens and as ligands for natural killer (NK) cells, is well established. A total of 10 different serologically defined HLA-Cw antigen specificities (Cw1-Cw10) are encoded by the C locus; however, there are now 151 different alleles that can be identified by molecular methods. Serological definition of Cw alleles therefore includes 20-50% blanks, which cannot be detected by the available antisera. We used the molecular method of polymerase chain reaction (PCR)-based sequence-specific amplification and probe hybridization to define Cw alleles in 91 individuals from the Maratha community, and compared the data with data for 92 serologically typed Maratha individuals from India. We identified Cw*12, Cw*14, Cw*15, Cw*16 and Cw*18, along with the serologically identified Cw*01, Cw*02, Cw*03, Cw*04, Cw*06 and Cw*07 alleles. The HLA-Cw blank allele frequency in the Maratha was reduced from 0.5706 to 0.00. Furthermore, by using a molecular technique, it was possible to identify novel allele subtypes, such as Cw*0104, Cw*0203 and Cw*0707, and a high frequency of Cw* 1801 in the Maratha community compared with other Indian and world populations. Our results will have clinical implications in related and unrelated HLA-matched bone marrow transplantation in India.

Alleles↗
PubMed2005

Megaloblastosis: from morphos to molecules.

OBJECTIVE: Megaloblastosis (i.e., megaloblastic transformation of erythroid precursor cells in the bone marrow) is the cytomorphological hallmark of megaloblastic anemia resulting from vitamin B12 and folate deficiency. It is characterized by a finely stippled lacy pattern of nuclear chromatin, which is believed to be an expression of deranged cellular DNA synthesis. However, the molecular basis of these cytomorphological aberrations still remains obscure. The current presentation describes the results of our studies on some molecular events associated with the development of megaloblastosis. METHODS: Transmission electron microscopy was used to study megaloblasts as well as DNA fibers extracted from megaloblastic and normoblastic bone marrows with and without treatment with proteinase K during the extraction procedure; cellular DNA synthesis in bone marrow cultures was studied by incorporation of 3H-thymidine and deoxyuridine suppression test, while histone biosynthesis in bone marrow cells was studied by in vitro incorporation of 3H-tryptophan, 3H-lysine and 3H-arginine into histones. RESULTS: Derangement of DNA synthesis occurred due to an impaired de novo pathway of thymidylate synthesis in both vitamin-B12- and folate-deficient human megaloblastic bone marrows as well as in the bone marrows of rhesus monkeys and rats with experimentally induced folate deficiency. Interestingly, folate-deficient monkeys developed frank megaloblastic bone marrows, but folate-deficient rats did not. On the other hand, megaloblastic changes in the bone marrow of human patients with myelodysplastic syndrome and erythroleukemia were not associated with this DNA synthetic abnormality. Biosynthesis of predominantly arginine-rich histones in megaloblastic bone marrows was markedly reduced as compared to normoblastic bone marrows, which was consistently associated with elongation and despiralization of chromosomes and finely stippled nuclear chromatin in megaloblasts. CONCLUSION: The impaired biosynthesis of predominantly arginine-rich nuclear histones appeared to be a common molecular event (a denominator) underlying the development of megaloblastosis with or without abnormal DNA synthesis.

Adolescent↗
PubMed2005

Maternal origin of extra marker chromosome 1Q31.1-qter and 13pter-q12.12 in a child with dysmorhic features.

Maternal origin of extra marker chromosome Iq31.l-qter and 13pter-q12.12 in a child with dysmorphic features: We describe a twenty-days-old female child with dysmorphic features and chromosomal analysis with GTG-banding revealed an extra marker chromosome. Fluorescence in situ hybridization (FISH) study of extra marker chromosome confirmed to be maternal der(13) chromosome, contained 1q31.1-qter and 13pter-q11 chromosomal material and resulted from a maternal balanced translocation t(1;13)(q31.1; q12.12). The child had the majority of trisomy 1q clinical features: dysmorphic features, micropthalmia, high arched palate, long philthrum, micrognathia, hypertelorism, low set ears, short sternum, overlapping fingers, valgus of wrists, right knee and ankle joints were in flexion contractures. This is the first case of trisomy 1q with an extra marker chromosome which also contained chromosome 13pter-q12.12 material.

Abnormalities, Multiple↗
PubMed2004

Role of epsilon amino caproic acid in the management of haemophilic patients with inhibitors.

We managed bleeding crisis in 10 consecutive severe haemophilic patients with inhibitors (eight had an inhibitor level of >5 BU mL(-1)) mainly with the antifibrinolytic agent, i.e. epsilon amino caproic acid (EACA). EACA was used by local, oral or intravenous routes either in combination or separately. Five patients developed inhibitors postoperatively and among the remaining five, four had recurrent haemarthrosis or soft tissue bleeds and one patient presented with severe gastrointestinal bleeding without demonstrable lesion. In all the patients, addition of EACA to their management protocol resulted in stoppage and/or reduced frequency of bleeding. In six of 10 patients, the results were excellent; of these six patients, five developed inhibitors postoperatively. Although a reduction in the frequency of bleeding was observed in patients with haemarthrosis and soft tissue bleed, it was not spectacular and the patients required additional therapy. Hence the results could be described as poor. No patient needed to stop the medicine because of the side-effect of EACA. Symptoms like mild nausea and vertigo were seen as the side-effects of this medicine when high intravenous dosage was administered. EACA thus appears to be an excellent adjuvant therapy for haemophilic patients with inhibitors. Besides its well-recognized antifibrinolytic activity, EACA may have additional mechanisms of action in haemophilic patients with inhibitors. More extensive use of this cheap and safe product is warranted in haemophilic patients with inhibitors. If larger studies confirm this observation, then using antifibrinolytics will allow substantial reduction of FEIBA or activated prothrombin complex (APCC) usage in such patients without necessarily increasing the thrombotic complications or reduction of the clinical efficacy, when compared with higher dosage of FEIBA or APCC alone. This will lead to substantial financial savings in countries where up to 35% of severe haemophilia A patients develop inhibitors.

Adolescent↗
PubMed2004

An interplay of alleviating mutations in the clinical phenotype of beta-thalassaemia intermedia.

Prediction of a beta-thalassaemia major phenotype from the beta-genotype is generally relatively straightforward. However, despite the ability to accurately define the beta-thalassaemia mutations, prediction of a beta-thalassaemia intermedia phenotype from the genotype sometimes remains problematic and this has important implications in genetic counselling and prenatal diagnosis. We report a 11-year-old Indian male child with a thalassaemia intermedia phenotype. beta-Globin gene analysis of the family showed that he was a compound heterozygote with the -88 (C-->T) beta+-mutation and the IVS1 nt 130 (G-->C) beta0-mutation. Both these mutations are rare among Indians. The propositus was also found to be heterozygous for the XmnI polymorphism and had a normal alpha-genotype. In this family interplay of two alleviating mutations (a milder promoter mutation along with a gene for raised HbF) might have synergistically compensated for lack of globin chains in the patient. Hence, the nature of the beta-genotype as well as the knowledge of the presence or absence of alleviating factors will help the clinician to decide whether early commencement of a regular transfusion regime is necessary.

Child↗
PubMed2004

Thrombophilia in coronary artery disease: a double jeopardy.

Thrombophilia can be defined as an increased risk of thrombosis. The central event to the pathogenesis of any thrombotic episode is the perturbation of haemostasis, the cause of which may be genetic or environmental. The clinical manifestations of the chronic development of coronary artery atheroma are angina and acute myocardial infarction. In recent years literature is emerging on the role of different factors of blood coagulation in arterial thrombosis. Different coagulation factors, natural anticoagulants, platelet antigens and other factors such as homocysteine, lipoprotein (a), have been studied as risk factors for coronary artery disease (CAD). The results of many of these studies are contradictory. In India, there is an alarming rise in the number of young patients with myocardial infarction (MI) and an interesting feature is that a large majority of these patients lack the conventional risk factors. There have been scattered studies on the thrombophilia status among Indians. The management of thrombophilia can be done by a regimen of different drugs which has been evaluated in different clinical trials. Since the cost of thrombophilia investigations is quite phenomenal for a developing country like India, the selection of these investigations assumes an utmost importance.

Biomarkers↗