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V Chowdhury

Publications and source records attributed to V Chowdhury.

At least 19 recordsLinked to original sources
PubMed2002

An unusual presentation of the Papillon-Lefevre syndrome as recurrent liver abscesses.

The Papillon-Lefevre syndrome is a rare genetic disorder with a predisposition to severe infections. We describe Papillon-Lefevre syndrome in a 17 year old boy from a family where four out of eight siblings were affected with this disease and who presented with recurrent pyogenic liver abscesses over a period of 9 years, an association never previously reported.

Adolescent↗
PubMed1999

Profuse variceal hemorrhage as a presenting feature of pancreatic adenocarcinoma in a young non-icteric patient.

Pancreatic adenocarcinoma can present with a vast spectrum of rare manifestations. It usually occurs after the age of 50 years, the peak incidence being in sixth and seventh decades. We report a previously asymptomatic subject of pancreatic adenocarcinoma who presented for the first time with massive upper gastrointestinal hemorrhage. Endoscopy revealed ruptured esophageal varices which were secondary to tumour-induced thrombosis of the portal vein. Besides the uncommon mode of presentation, the patient was unusual because of his young age. Further, he was non-icteric at the time of presentation and remained so throughout the clinical course despite having a large lesion in the head of the pancreas.

Adenocarcinoma↗
PubMed1997

Fine-needle aspiration diagnosis of carotid body tumor: report of a case and review of experience with cytologic features in four cases.

A 45-yr-old female presented with a left upper cervical swelling of 4 yr duration. The clinical suspicion of carotid body tumor (CBT) was confirmed by imaging findings, fine-needle aspiration (FNA) cytology, and histology of the resected tumor. Review of our experience with four cases including the present one during 10 yr (1984-1994) showed that the age of the patients ranged from 35 to 45 yr with a mean of 40.8 yr. All four cases were females and had left-sided upper cervical swelling. Clinically one case was diagnosed as cervical lymphadenopathy and there was clinical suspicion of CBT in two cases. Findings of digital subtraction angiogram in four cases and ultrasonography including Doppler ultrasound vascular imaging in three cases were consistent with CBT. The cytodiagnosis was CBT in three cases and inadequate (blood only) in one case. The analysis of detailed cytologic features in three cases revealed blood-rich aspirate with poor to moderate cellularity, indistinct cell outline, and acinar formation. Giant bare nuclei, spindle-shaped tumor cells, and cytoplasmic granulations were observed in two cases each. Histopathology of the resected tumors in two cases confirmed the cytodiagnosis of CBT. FNA cytology played a useful role in arriving at a tissue diagnosis of this rare neoplasm.

Adult↗
PubMed1996

Factor V Leiden (FV R506Q) in families with inherited antithrombin deficiency.

We investigated the presence of the gene mutation of factor V, FV R506Q or factor V Leiden, responsible for activated protein C resistance, in DNA samples of 127 probands and 188 relatives from 128 families with antithrombin deficiency. The factor V mutation was identified in 18 families. Nine families were available to assess the mode of inheritance and the clinical relevance of combined defects. The factor V and antithrombin genes both map to chromosome 1. Segregation of the defects on opposite chromosomes was observed in three families. Co-segregation with both defects on the same chromosome was demonstrated in four families. In one family a de novo mutation of the antithrombin gene and in another a crossing-over event were the most likely explanations for the observed inheritance patterns. In six families with type I or II antithrombin deficiency (reactive site or pleiotropic effect), 11 of the 12 individuals with both antithrombin deficiency and the factor V mutation developed thrombosis. The median age of their first thrombotic episode was 16 years (range 0-19); this is low compared with a median age of onset of 26 years (range 20-49) in 15 of 30 carriers with only a defect in the antithrombin gene. One of five subjects with only factor V mutation experienced thrombosis at 40 years of age. In three families with type II heparin binding site deficiencies, two of six subjects with combined defects experienced thrombosis; one was homozygous for the heparin binding defect. Our results show that, when thrombosis occurs at a young age in antithrombin deficiency, the factor V mutation is a likely additional risk factor. Co-segregation of mutations in the antithrombin and factor V genes provides a molecular explanation for severe thrombosis in several generations. The findings support that combinations of genetic risk factors underly differences in thrombotic risk in families with thrombophilia.

Adolescent↗
PubMed1995

Antithrombins Southport (Leu 99 to Val) and Vienna (Gln 118 to Pro): two novel antithrombin variants with abnormal heparin binding.

We report the characterization of three variant antithrombins with reduced heparin binding as the primary abnormality. Two of these variants, antithrombin Southport (Leu 99 to Val, 2759 C to G) and antithrombin Vienna (Gln 118 to Pro, 5349 A to C) were novel, whereas the third, Pro 41 to Leu, has been previously described as antithrombin Basel. All three variants exhibited reduced binding for heparin on crossed immunoelectrophoresis and in a quantitative monoclonal antibody-based assay. The mutations were characterized by direct sequence analysis of enzymatically amplified genomic DNA and all affected individuals were heterozygous for the mutations. These three mutations do not occur at the sites of the basic amino acids directly involved in heparin binding nor do they result in a change in charge of the affected residue. It seems probable that they reduce heparin affinity either by perturbing the initial contact site involved in the heparin-binding domain (Arg 47, Arg 129 and possibly Arg 24), or by preventing the subsequent heparin-induced conformational change.

Adult↗
PubMed1994

(ATT) trinucleotide repeats in the antithrombin gene and their use in determining the origin of repeated mutations.

Two (ATT) trinucleotide repeat polymorphisms have been identified in the tails of Alu repeat elements in intron 5 of the antithrombin gene. The frequency and distribution of allele sizes for the Alu 5 and Alu 8 tail polymorphisms have been defined in a sample Caucasian population. The Alu 5 polymorphism has two alleles while that of Alu 8 has 10 alleles with a heterozygosity of 0.83. These polymorphisms have been used in combination with four previously described polymorphisms within the antithrombin gene to construct antithrombin gene haplotypes in the sample Caucasian population. Twenty-two different haplotypes were observed, with the Alu 8 polymorphism being particularly useful in subdividing the core haplotype based on the previously identified polymorphisms. The haplotype data were used to investigate the origin of repeat mutations within the antithrombin locus. We compared the haplotypes associated the mutant antithrombin genes in five families with the mutation 2759C-->T (L99F) and five families with the mutation 5381C-->T (R129Stop). The mutation 2759C-->T (L99F), which occurs within a non-CpG dinucleotide, was carried on a gene associated with an identical haplotype in each of the five families. The mutation 5381C-->T (R129Stop), a single base substitution within a CpG dinucleotide, was associated with at least two different haplotypes. The findings suggest a founder effect in the five families sharing the 2759C-->T (L99F) and at least two independent origins for the CpG dinucleotide mutation 5381C-->T (R129Stop).

Antithrombins↗
PubMed1994

Homozygous antithrombin deficiency: report of two new cases (99 Leu to Phe) associated with arterial and venous thrombosis.

Inherited antithrombin deficiency is associated with an increased risk of thrombosis, primarily venous rather than arterial. Most affected individuals have inherited only a single copy of an abnormal antithrombin (AT) gene. Homozygously affected individuals, although rare, have a severe thrombotic history of early onset and often affecting the arteries. We report two new cases of type II HBS (heparin binding site) deficiency in which the propositi are homozygous for the previously reported mutation 99 Leu to Phe, and who have a severe thrombotic history. These cases are considered alongside existing homozygote and compound heterozygote cases.

Antithrombins↗
PubMed1994

Norms for renal parenchymal volume in Indian children.

Seventy-seven clinically normal children with kidneys of normal size were examined sonographically. Renal parenchymal volumes were calculated and related to age, height, body weight and body surface area; growth charts were constructed. A significant correlation was found between the renal parenchymal volume and the body somatometric parameters. The present report thus provides norms for renal parenchymal volume in Indian children.

Anthropometry↗
PubMed1993

Complete nucleotide sequence of the antithrombin gene: evidence for homologous recombination causing thrombophilia.

Antithrombin is the principle regulator of thrombin and other blood coagulation proteinases. It is a member of the serpin family of proteinase inhibitors. The genomic sequence of the antithrombin locus has been completed, revealing a gene spanning 13,477 base pairs from the transcription start site to the poly(A) addition signal. Nine complete and one partial Alu repeat elements were identified within the introns of the gene, with all but one orientated in the reverse direction. Inherited deficiency of antithrombin is associated with a venous thrombotic tendency. Restriction fragment mapping of the antithrombin genes in an individual with type I antithrombin deficiency identified an intragenic deletion in one allele. Localization of the deletion breakpoints involved restriction analysis and direct sequencing of amplified DNA spanning the deletion site. The deletion removed 2761 base pairs, affecting exon 5 and flanking introns, with the deletion ends contained within the left components of two Alu elements. It is likely, therefore, that the deletion arose by homologous recombination between the two Alu elements.

Adolescent↗
PubMed1993

Identification of nine novel mutations in type I antithrombin deficiency by heteroduplex screening.

We have utilized DNA heteroduplex detection as a method for screening sequences of the antithrombin (AT) gene for the presence of mutations. Affected individuals from 41 kindreds with type Ia antithrombin deficiency were investigated. Heteroduplexes were detected in 12 cases; direct sequencing of the appropriate exons revealed nine cases with novel mutations, and two with previously described mutations. In addition, a new polymorphism in the 5' untranslated region was characterized. The defects included minor insertions and deletions which lead to the removal of intact codons or premature termination, and single base substitutions leading to premature termination or amino acid substitution. In all cases, the affected individuals were heterozygous for the defect and variant AT protein was not detected. In keeping with previous reports the defects associated with type Ia AT deficiency are extremely heterogeneous, the vast majority being point mutations. This study also demonstrates the efficiency of hydrolink gel electrophoresis as a method of screening for unknown mutations by heteroduplex detection.

Antithrombins↗
PubMed1992

Inversion of chromosome 16 with the Philadelphia chromosome in acute myelomonocytic leukemia with eosinophilia. Report of two cases.

Two cases are described with the rare combination of inv(16)(p13q22), strongly associated with acute myelomonocytic leukemia with eosinophilia, M4Eo, and the Philadelphia translocation, t(9;22)(q34;q11), hallmark of chronic myeloid leukemia (CML) and rarely found, (less than 1%), in acute nonlymphocytic leukemia. The patients were: case 1, a 9-year-old girl presenting with a white blood cell count (WBC) 42 x 10(9)/L with 32% blasts and bone marrow with blasts and eosinophil precursors consistent with M4Eo, and case 2, a 25-year-old man with WBC 34.7 x 10(9)/L with 13% blasts and bone marrow with features of M4Eo and basophilia. Both patients achieved remission but died following bone marrow transplantation in first remission (case 1) or in relapse (case 2). Cytogenetic findings were: case 1, at diagnosis, 46,XX,inv(16)(p13q22)(21)/46,XX,t(9;22) (q34;q11),inv(16)(8)/46,XX(10), and case 2, at diagnosis, 46,XY,t(9;22) (q34;q11),inv(16)(p13q22) (16) and in remission, 46,XY,t(9;22)(q34;q11) (1)/46,XY (24). Investigation of the breakpoint on 22 in case 1 with Southern blotting and the polymerase chain reaction demonstrated the presence of a p190 mRNA and a breakpoint typical of acute leukemia. Thus a diagnosis of M4Eo was supported by clinical and cytogenetic sequelae in each case; the Ph in case 1 was apparently secondary to inv(16), in case 2 the Ph probably preceded inv(16) in the etiology of the leukemia.

Adult↗
PubMed1992

Autoimmune hemolytic anemia associated with anti-Sc1.

A case of autoimmune hemolytic anemia (AIHA) in a young child is described. The hemolysis was resistant to steroid therapy but responded to splenectomy and intravenous immunoglobulin. The autoantibody was shown to be anti-Sc1 by both serologic and immunoblotting techniques. This seems to be the first report of an autoanti-Sc1 detected by immunoblotting and the first example of AIHA in a child caused by autoanti-Sc1.

Anemia, Hemolytic, Autoimmune↗
PubMed1992

Computed tomography evaluation of esophageal carcinoma.

Forty patients of histologically proven esophageal carcinoma were subjected to computed tomography (CT) with the objective to assess its reliability in preoperative evaluation of these patients. The findings were confirmed on surgery in twenty five of these patients, thought to be resectable. Bronchoscopy was performed to evaluate bronchial tree in cases of tumor of upper and middle third of esophagus. CT was found to be sensitive in predicting the location and size of tumor, in assessing invasion of tracheo-bronchial tree, spread to liver, celiac and left gastric nodes. However, it was not successful in picking up metastatic spread to local periesophageal nodes in five cases and celiac in one case. The study concluded CT should be carried out for preoperative evaluation of esophageal carcinoma to select operable cases and avoid unnecessary radicle surgery in advanced cases.

Adult↗