Biomedical subjects

F Koppitch

Publications and source records attributed to F Koppitch.

8 recordsLinked to original sources

PubMed1997

Cytogenetic aberrations and DNA ploidy in soft tissue sarcoma. A Southwest Oncology Group Study.

We performed cytogenetic analysis and determined DNA content by flow cytometry (FCM) on freshly disaggregated tumor biopsies from 45 patients with soft tissue sarcomas (STS). Cytogenetically aberrant clones characterized 30 (67%) tumors, with the remaining 15 yielding normal karyotypes with or without nonclonal aberrations. No tumors with multiple unrelated clones were observed. Among the 30 tumors with clonally abnormal karyotypes, 21 (70%) had near-diploid stemlines, six were near-triploid and three were near-tetraploid. Ten of the clonally aberrant tumors contained nonrandom chromosomal translocations characteristic of histologic subtypes. Overrepresentation of chromosomes 7 and 8 were common numerical aberrations. Structural aberrations most often involved chromosomes 1, 7, 9, 12, and 14. Clustering of breaks in 9p resulting in partial loss of the short arm was frequent. Unstable aberrations including rings, dicentrics, large markers, small numbers of double minutes, and telomeric associations were seen in nine tumors. With FCM, 27 (60%) tumors had aneuploid DNA content and 18 (40%) were DNA diploid. Of those 18 DNA diploid tumors, 11 showed clonal karyotypic aberrations. In addition, apparent discrepancies between the results of the cytogenetics and FCM with respect to ploidy pattern were seen in 13 samples; 11 had DNA content in the peritriploid to peritetraploid range but the corresponding karyotype was normal or near-diploid. When the findings of the cytogenetics and DNA content analyses were combined, an abnormal cell population by one or both methods was detected in 38 (84%) tumors. The concurrent application of standard cytogenetics and DNA ploidy by FCM provide complementary information confirming a high incidence of genetic alterations in STS.

Adolescent↗

PubMed1995

A haploid expressed gene cluster exists as a single chromatin domain in human sperm.

Mammalian spermiogenesis is marked by the initial disruption of the nuclear-histone-DNA complex by the transition proteins for ultimate replacement with protamines. The genes for three of these low molecular weight basic nuclear proteins exist as a single linear array of PRM1, PRM2, and TNP2 on human chromosome 16p13.2. To begin to address the mechanism governing their transcriptional potentiation, a region of approximately 40 kilo-bases of the human genome encompassing these genes was introduced into the germ line of mice. Fluorescence in situ hybridization and Southern analysis showed that this segment of the human genome integrated into independent chromosomal sites while maintaining its fidelity. Transcript analysis demonstrated that the expression of the endogenous mouse protamine Prm1 and Prm2 genes as well as the mouse transition protein Tnp2 gene were expressed along with their human transgene counterparts. The pattern of expression of these transgenic human genes within this multigenic cluster faithfully represented that observed in vivo. In addition, all members of this transgenic gene cluster were expressed in proportions similar to those in human testis. Copy number-dependent and position-independent expression of the transgenic construct demonstrated that the corresponding biological locus was contained within this segment of the human genome. Furthermore, DNase I sensitivity established that in sperm the human PRM1-->PRM2-->TNP2 genic domain was contained as an approximately 28.5-kilobase contiguous segment bounded by an array of nuclear matrix associated topoisomerase II consensus sites. This is the first description of a multigenic male gamete-specific domain as a fundamental gene regulatory unit. A model of haploid-specific gene determination is presented.

Amino Acid Sequence↗

PubMed1995

BCR/ABL fusion located on chromosome 9 in chronic myeloid leukemia with a masked Ph chromosome.

A reciprocal translocation, t(10;22)(q22;q11), resulting in a masked Ph chromosome was identified in a patient diagnosed with chronic myeloid leukemia (CML). Both homologs of chromosome 9 were of the normal pattern. Two signals for the ABL probe, both of them hybridized to chromosome 9, were demonstrated via fluorescence in situ hybridization (FISH). Furthermore, cohybridization with two differently labeled BCR/ABL translocation DNA probes indicated a BCR/ABL fusion apparently located on 9q34. Molecular studies revealed a rearrangement of the BCR region and expression of a chimeric BCR/ABL mRNA of CML configuration. These findings indicate that the BCR/ABL fusion resulted from an unusual relocation of the BCR gene from its normal position on 22q11 to 9q34 adjacent to the ABL gene.

Chromosomes, Human, Pair 9↗

PubMed1991

Transabdominal chorionic villus sampling for rapid karyotyping in advanced gestation.

Late pregnancy fetal karyotyping is not employed often because a clinical decision about labor and delivery may be required before the results would be available. However, percutaneous umbilical blood sampling (PUBS) has been used recently to obtain fast karyotypes. We have extended our chorionic villus sampling (CVS) procedure to the second and third trimesters and compared the results obtained with late CVS and PUBS. CVS karyotypes were obtained faster and may be technically easier to perform.

Chorionic Villi Sampling↗

PubMed1987

Trisomy 21 in acute promyelocytic leukemia.

We present a case of a 64-year-old male, diagnosed to have acute promyelocytic leukemia with trisomy 21. He came to the hospital with bleeding secondary to disseminated intravascular coagulation. Promyelocytes in the blood and bone marrow contained abundant, prominent azurophilic granules. Cytogenetic studies revealed trisomy 21. The karyotypic abnormality reverted back to normal 46,XY, pattern after chemotherapy. The typical morphologic and cytogenetic features of acute promyelocytic leukemia are briefly discussed.

Bone Marrow↗

PubMed1984

Acute basophilic leukemia.

Acute basophilic leukemia was diagnosed in a 61-year-old black woman on the basis of 85 to 90 percent basophils in the peripheral blood as well as bone marrow and very high serum histamine level (more than 10,000 ng/ml). These complications occurred as a transformation from essential thrombocythemia. Accompanying this transformation, there was also cytogenetic change from 46XX karyotype to 46XX 2p+ in 66 to 90 percent of cells in the bone marrow. This may be the first reported occurrence of transformation of essential thrombocythemia into acute basophilic leukemia.

Acute Disease↗

PubMed1982

Karyotypic polymorphism in acute myelofibrosis.

Acute myelofibrosis (AMF) was diagnosed in a 59-yr-old black male in September 1978, on the basis of pancytopenia, lack of hepatosplenomegaly, fibrosis of the marrow, and paucity of teardrop red blood cells in the peripheral blood. Since then the patient has demonstrated an unusually long survival of 36 mo with a changing cytogenetic course. His initial 46, XY normal karyotype changed in 20 mo to trisomy 8, followed 1 yr later by 1:4 translocation in peripheral blood. Simultaneously with these changes, the fibrosis in the bone marrow progressively decreased, ultimately terminating in chronic granulocytic leukemia-like presentation with reversal to 46, XY karyotype. Fibroblast culture failed to show any evidence of cytogenetic abnormalities. The disappearance of fibrosis confirmed by trichrome and reticulin stains and lack of cytogenetic abnormalities in fibroblasts confirms the secondary role of fibrosis.

Acute Disease↗

PubMedDate not supplied

Chorionic villi sampling changes maternal serum alpha-fetoprotein.

Second trimester amniocentesis has traditionally been utilized for prenatal genetic diagnosis. Chorionic villi sampling (CVS) is presently offered as an alternative. The occurrence of fetomaternal bleed (FMB) during CVS could increase the rate of post sampling abortion and, additionally, be of significance in patients at risk for isoimmunization. Detection and quantitation of FMB can be accomplished by the determination of changes in maternal serum alpha-fetoprotein (MSAFP) before and after CVS.

Biopsy↗