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Biomedical subjects

F Hecht

Publications and source records attributed to F Hecht.

349 records · Page 20Linked to original sources
PubMedDate not supplied

Bone marrow monosomy 7: hematologic and clinical manifestations in childhood and adolescence.

The hematologic manifestations and clinical course are described for six children and adolescents with bone marrow monosomy 7. One child with secondary acute myelogenous leukemia had monosomy 7 plus a marker chromosome; the remaining patients had marrow monosomy 7 as the only karyotypic abnormality. The hematologic abnormalities were diverse, but the majority of patients had a smoldering preleukemic or myeloproliferative phase. Leukemic blasts were either undifferentiated or demonstrated evidence of myeloid differentiation. All patients responded poorly to antileukemic therapy. Bone marrow monosomy 7 was observed in one patient with severe marrow hypoplasia. Antileukemic therapy in another patient with greater than 30 per cent marrow blasts was associated with the development of a bone marrow myeloproliferative disorder with persistence of the monosomy 7 karyotype. We speculate that monosomy 7 may be a specific marker for a pluripotent hematopoietic stem cell abnormality that is associated with either blastic leukemia or a myeloproliferative disorder.

Acute Disease↗
PubMedDate not supplied

Construction of long-range restriction maps in human DNA using pulsed field gel electrophoresis.

Pulsed field gel electrophoresis (PFGE) is a powerful new tool for genetic analysis that can be applied to a variety of problems concerning genome structure and organization. This technique uses an agarose gel matrix to separate DNA molecules in a size range from 40 kb to 2,000 kb, molecules far larger than the maximum separable using standard agarose gel electrophoresis. The PFGE method can be used to separate the intact chromosomes from lower eukaryotes or to separate very large DNA fragments from higher eukaryotes generated by digestion with restriction endonucleases whose cleavage sites are rare. This paper describes the use of PFGE for construction of long-range restriction maps in the human genome and includes detailed methods for all steps. A pulsed field gel device that utilizes a rotating platform for altering the applied electric field is also described. Map construction is illustrated using a cloned DNA fragment (D3S2) from human chromosome 3. Several technical problems specific for mammalian genomes are discussed.

Blotting, Southern↗
PubMedDate not supplied

Mutations of the Kirsten-ras proto-oncogene in human preleukaemia.

The myelodysplastic syndrome (MDS) or preleukaemia is a haematological disorder characterized by low blood counts, bone marrow cells of abnormal appearance and progression to acute leukaemia in as many as 30% of patients. The distinctive preleukaemic and leukaemic phases of this disease make it an attractive model for neoplastic progression in human tumours. We reasoned that, because dominantly transforming genes (such as mutant alleles of ras proto-oncogenes) are found so frequently in acute leukaemia, the search for these genetic lesions during the clinical course of patients with MDS might give us insight into the function of oncogenes in leukaemogenesis. We report here that bone marrow cells from two of four patients with preleukaemia, and from one patient who progressed to acute leukaemia from MDS, contained a transforming allele of the Ki-ras proto-oncogene. In one preleukaemic patient, a novel mutation in codon 13 of this ras gene was detected in bone marrow cells harvested 1.5 years before the acute leukaemia developed. Our findings provide evidence that ras mutations may be involved in the early stages of human leukaemia.

Adult↗