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Mammen Chandy

Publications and source records attributed to Mammen Chandy.

25 records · Page 2Linked to original sources

Arsenic trioxide in the treatment of newly diagnosed acute promyelocytic leukemia: a single center experience.

Arsenic trioxide (As(2)O(3)) has been found effective in the treatment in the treatment of acute promyelocytic leukemia (APML). Most studies with As(2)O(3) involve patients with APML who have relapsed following standard therapy. Between January 1998 and July 2000, 14 patients were recruited for an ongoing trial of As(2)O(3) in the treatment of newly diagnosed APML. Arsenic trioxide was administered at a dose of 10 mg/day until complete remission (CR) was achieved. Afterward, a consolidation course and a maintenance schedule consisting of As(2)O(3) as a single agent were administered over 6 months. There were 3 early deaths related to intra-cerebral hemorrhage: two on day 3 and one on day 4. Of the 11 evaluable patients, one died on day 21 secondary to uncontrolled sepsis, while the remaining 10 (91%) have attained CR. The average time to CR was 52.3 days (range: 34-70 days). One patient developed an isolated central nervous system (CNS) relapse and subsequently went into a second CR following therapy with triple intrathecal chemotherapy, cranial irradiation, and an additional 4-week course of systemic As(2)O(3). This patient, as well as the remaining nine, has continued to remain in CR at a median follow up of 15 months (range: 2-33 months). Eight out of 10 patients achieved molecular remission at variable periods during their consolidation and maintenance schedules. One patient developed an ATRA syndrome and was administered daunorubicin (40 mg/day) for 2 days. The side effects with this therapy were minimal and did not require cessation of therapy in any patient. There was no significant hepatic toxicity. In our experience, arsenic trioxide is effective in inducing and maintaining remission in patients with APML with minimal side effects. The optimal regimen and total dose required need to be defined.

Adolescent↗

A complex karyotype involving chromosomes 3, 6, 11, 12, and 22 in adult acute lymphoblastic leukemia.

Complex chromosomal abnormalities are rare in adult patients with acute lymphoblastic leukemia (ALL). Using molecular methods, we characterized a complex karyotype involving chromosomes 3, 6, 11, 12, and 22 in a 38-year-old man with ALL. Cytogenetic analysis revealed the following karyotype: 46,XY,der(3)t(3;?6)(q22;?p21), - 6,add(11)(q23),add(12)(p13), + mar[10]/46,XY[19]. Because patients with 11q23 abnormalities have a poor prognosis and require aggressive treatment, we used fluorescence in situ hybridization (FISH) to fully characterize the abnormalities. FISH analysis showed no rearrangement of the MLL or ETV6-CBFA2 (TEL-AML1) genes; the wild-type ETV6 allele was deleted in most cells. The revised karyotype after the FISH analysis was as follows: 46,XY,der(3)t(3;12)(p13;p?13)del(3)(q21),der(6)inv(6)(p21q21)ins(6;3)(q21;q21q25),der(11)t (3; 11)(q25;q23),der(12)t(11; 12)(q23;p?12),t(12;22)(p13;q13). Although structural abnormalities involving 11q23 and 12p13 bands were identified by conventional cytogenetics, this report clearly demonstrates that molecular assays are needed to fully characterize gene rearrangements, complex translocations as well as to assign patients to the appropriate treatment group.

Adult↗

A novel beta-thalassemia mutation in an Asian Indian.

A novel 7 bp deletion in exon 2 of the beta-globin gene in a 9-year-old boy originating from the eastern part of India is described. This deletion causes a shift in the reading frame of the beta-globin coding sequences, and consequently, a premature translation termination due to the creation of a stop codon at position 86. A slipped strand mispairing during DNA replication repair is proposed as the potential mechanism in generating this small deletion.

Adult↗

Coexistence of a novel beta-globin gene deletion (codons 81-87) with the codon 30 (G-->C) mutation in an Indian patient with beta0-thalassemia.

We identified and characterized a novel beta0-thalassemia mutation due to the deletion of 22 bases from codons 81 through 87, found in a compound heterozygous state with codon 30 (G-->C) in a patient originating from West Bengal State, India. The deletion causes a shift in the reading frame of the coding sequence and creates a stop codon at position 81. Direct and inverted repeat sequences present in the deleted region might be involved in the origin of this mutation. The patient had moderate anemia and did not require blood transfusions (thalassemia intermedia).

Base Sequence↗

Prenatal diagnosis of Glanzmann thrombasthenia.

BACKGROUND: Glanzmann thrombasthenia (GT) is an autosomal recessive disorder of platelet function, which results in major morbidity due to persistent, spontaneous, mucocutaneous bleeding and menorrhagia in women. Platelet transfusions are often needed to control the bleeding. Glanzmann thrombasthenia results from mutations in the genes located on chromosome 17q21-23, encoding the platelet glycoprotein (GP) IIb/IIIa receptor. METHODS: This report describes, for the first time in India, the prenatal diagnosis performed in a family who had a child with GT. As the molecular defect had not been identified at the time of chorionic villus sampling (CVS), prenatal diagnosis was done by linkage assessment. Haplotype analysis was performed using polymorphic markers on chromosome 17q 12-21, which included the dinucleotide repeat polymorphisms (CA)n in BRCA1 gene and locus D17S579 and (CT)n within GP IIIa intron 6, and the known restriction fragment length polymorphism (RFLP) markers Fok I (GP IIb exon 26), Taq I (GP IIIa exon 8) and Sma I (GP IIIa exon 9). The specific mutation in this family was subsequently confirmed. RESULTS: Both parents and the foetus were heterozygous for all the dinucleotide repeat polymorphisms and the affected child was homozygous. Both parents and the affected child were homozygous for Fok I RFLP. The father was heterozygous, and the mother, affected child and foetus were homozygous for Taq I and Sma I. The Fok I RFLP was identical for all the family members and hence did not provide any information for haplotype analysis (foetus not tested). CONCLUSION: The findings from dinucleotide repeat polymorphisms in BRCA1, D17S579, and GP IIIa intron 6 and the Sma I and Taq I RFLPs in GP IIIa strongly suggested that the foetus had inherited the father's mutant and the mother's normal alleles. Hence, the foetus was diagnosed to be a heterozygous carrier of GT by haplotype analysis. A private sequence alteration was later identified in the affected child in GP IIIa IVS1 (-14C --> A). The parents and foetus were heterozygous for this mutation. This confirmed the findings of the haploytpe analysis.

Adult↗