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U Surti

Publications and source records attributed to U Surti.

At least 73 records · Page 4Linked to original sources
PubMed1990

Genetics and biology of human ovarian teratomas. I. Cytogenetic analysis and mechanism of origin.

One hundred and two benign, mature ovarian teratomas and two immature, malignant teratomas were karyotyped and scored for centromeric heteromorphisms as part of an ongoing project to determine the chromosomal karyotype and the genetic origin of ovarian teratomas and to assess their utility for gene-centromere mapping. Karyotypic analysis of the benign cases revealed 95 46,XX teratomas and 7 chromosomally abnormal teratomas (47,XXX, 47,XX,+8 [two cases], 47,XX,+15, 48,XX,+7,+12 91,XXXX,-13 [mosaic], 47,XX,-15,+21,+mar). Our study reports on the first cases of tetraploidy and structural rearrangement in benign ovarian teratomas. The two immature cases had modal chromosome numbers of 78 and 49. Centromeric heteromorphisms that were heterozygous in the host were homozygous in 65.2% (n = 58) of the benign teratomas and heterozygous in the remaining 34.8% (n = 31). Chromosome 13 heteromorphisms were the most informative, with 72.7% heterozygosity in hosts. The cytogenetic data indicate that 65% of teratomas are derived from a single germ cell after meiosis I and failure of meiosis II (type II) or endoreduplication of a mature ovum (type III); 35% arise by failure of meiosis I (type I) or mitotic division of premeiotic germ cells (type IV).

Adolescent↗
PubMed1989

Deletion of terminal portion of 6q: report of a case with unusual malformations.

We present the necropsy findings of a 21-week-gestation male fetus with deletion of the terminal portion of long arm of chromosome 6 [46,XY,del(6)(q23----qter)]. Major anomalies include intrauterine growth retardation, facial anomalies, nuchal cyst, scoliosis, bilateral diaphragmatic hernias, persistent common atrioventricular canal, absent olfactory bulbs and agenesis of corpus callosum. In aberrations of chromosome 6q, patients usually have psychomotor retardation, somatic growth failure, and facial anomalies; nuchal cyst and bilateral diaphragmatic hernias have not yet been described.

Abnormalities, Multiple↗
PubMed1989

Chromosomal rearrangement in choriocarcinoma cell lines.

Malignant trophoblastic cells from four choriocarcinoma cell lines were evaluated in detail using Q, G, and C banding at various passages. The modal chromosome numbers for BeWo, DoSmi, ElFa, and Jar were 73, 71, 77, and 72, respectively. All the four tumor cell lines exhibited extensive chromosomal rearrangements with several consistent marker chromosomes in each. The majority of these markers have not been previously recognized in this malignancy. Rearrangements of chromosomes 1, 7, 9, 10, and 12 were noted in all four cell lines, but abnormalities of chromosomes 1 and 12 were not consistently present in ElFa and Jar, respectively. Telomeric associations were observed in two cell lines involving chromosomes 11 and 21 as well as chromosomes 3 and 12, resulting in two consistent marker chromosomes. A total of 86 breakpoints were involved in the consistent rearrangements observed in all four cell lines. Most of these breakpoints were located on chromosomes 1, 3, 9, 13, 12, 7, and 21, in order of frequency.

Choriocarcinoma↗
PubMed1988

Content and organization of the human Ig VH locus: definition of three new VH families and linkage to the Ig CH locus.

We present a detailed analysis of the content and organization of the human immunoglobulin VH locus. Human VH genes representing five distinct families were isolated, including novel members belonging to two out of three of the known VH gene families (VH1 and VH3) as well as members of three new families (VH4, VH5, and VH6). We report the nucleotide sequence of 21 novel human VH genes, many of which belong to the three new VH gene families. In addition, we provide a preliminary analysis of the organization of these gene segments over the full extent of the locus. We find that the five multi-segment families (VH1-5) have members interspersed over nearly the full 1500-2000 kb of the VH locus, and estimate that the entire heavy chain locus covers 2500 kb or less. Finally, we provide the first report of the physical linkage of the variable and constant loci of a human Ig gene family by demonstrating that the most proximal known human VH segments lie within 100 kb of the constant region locus.

Animals↗
PubMed1987

A hypervariable region at the D19S11 locus.

The polymorphic locus D19S11 consists of four closely linked RFLPs: alpha, beta, delta, and gamma on chromosome 19p13.2----19cen, revealed by subclones p13-1-82 and p13-2-21 from cosmid 1-13. Here, we report that p13-1-25, an additional subclone of c1-13, reveals three insertion/deletion RFLPs, alpha, epsilon, and phi, at the D19S11 locus. In situ hybridization of p13-1-25 to metaphase chromosomes from a carrier of a 19/X translocation with a breakpoint near the centromere confirms localization of D19S11 to 19p. Studies with hydatidiform moles have generated assignments of specific restriction fragments to these three loci, and genotypic studies in three-generation families have indicated that they are closely linked. Loci alpha (also detected by p13-1-82) and phi each have but two common alleles, whereas epsilon has at least 33 alleles, including a null allele. Fifty unrelated individuals tested displayed unique fragment patterns on Taq I blots probed with p13-1-25. Applications of this probe include monitoring loss of chromosome 19 during tumorigenesis, monitoring engraftment of donor bone marrow after transplantation, testing for paternity, and mapping disease genes on chromosome 19.

Chromosome Mapping↗
PubMed1987

Cytogenetics of trophoblasts from complete hydatidiform moles.

The risk of developing choriocarcinoma following a complete hydatidiform mole (CHM) is 2000-4000 times greater than the risk following a normal pregnancy. To understand more fully the increased susceptibility of the molar trophoblast to malignant transformation, we separated the trophoblastic cells from the stromal cells in 14 complete moles and cultured them for cytogenetic analysis. The numerical and structural abnormalities found were compared with those found in the trophoblasts from normal pregnancy and malignant choriocarcinoma cell lines. The percentage of polyploid cells was 2.8 times greater in molar trophoblasts than in normal trophoblasts. Although we found no consistent chromosomal abnormality in the molar trophoblasts, these cells were significantly more vulnerable to chromosomal breakage than the molar fibroblasts, normal trophoblasts, normal fibroblasts, and maternal decidual cells. Out of a total of 103 breakpoints observed in 338 cells, 42 coincided with known fragile sites, 18 with the location of protooncogenes, 27 with breakpoints reported in other neoplasia, and 18 with breakpoints found in four choriocarcinoma cell lines. The chromosomes in choriocarcinoma cell lines have hypotetraploid mode and many structural rearrangements. Our results suggest that the genetic instability found in the molar trophoblasts may be responsible for progressive karyotypic changes and greater susceptibility to malignant transformation.

Adolescent↗
PubMed1987

Hydatidiform mole: cytogenetically unusual cases and their implications for the present classification.

Unusual observations in hydatidiform moles are of clinical importance as well as of theoretical interest when the present subgrouping into partial or complete moles is evaluated, particularly in view of the more malignant potential of the latter. The purpose of the present review is to summarize, update, and evaluate information on moles with unusual karyotypes or origins. The important factor in the evolution of partial or complete moles appears to be the ratio of maternal to paternal chromosomes and not the ploidy of the tissue. Complete hydatidiform moles develop from androgenetic conceptions while partial hydatidiform moles develop from those conceptions in which the number of paternal sets of chromosomes exceeds the number of maternally derived sets. Rare cases inconsistent with this concept emphasize the value of examining morphologic features, cell ploidy, and genetic markers when one is attempting to classify hydatidiform moles.

Female↗
PubMed1987

Immunocytochemical localization of chorionic gonadotropin, placental lactogen, and placental alkaline phosphatase in the diagnosis of complete and partial hydatidiform moles.

Complete hydatidiform moles (CHMs) and partial hydatidiform moles (PHMs) represent different clinicopathologic entities with characteristic morphologic and cytogenetic findings. In the absence of cytogenetic data, the histologic distinction between these lesions and abortuses showing hydropic swelling (AHS) may be difficult. An immunocytochemical study analyzing the distribution of human chorionic gonadotropin (hCG), human placental lactogen (hPL), and placental alkaline phosphatase (PlAP) in CHMs, PHMs, and AHS was undertaken to determine whether the expression of these trophoblastic proteins might assist in the differential diagnosis. A total of 24 CHMs, 22 PHMs, and 13 AHS were selected on the basis of established morphologic criteria. Thirty-four specimens of abortuses without hydropic swelling and normal placentas, ranging from 6 to 24 weeks gestational age, were similarly analyzed. The immunocytochemical localization of the three trophoblastic proteins, predominantly in syncytiotrophoblast (ST), was scored using a semiquantitative scoring system. In CHMs hCG is widely distributed and PlAP is patchily distributed in ST regardless of the gestational age, whereas hPL tends to increase with increasing gestational age. In contrast, in PHMs hPL is more widely distributed in ST compared with CHMs regardless of gestational age, while PlAP increases with increasing gestational age; in PHMs the distribution of hCG is markedly less than in CHMs except early in the first trimester when the staining patterns are similar. The different patterns of distribution of hCG, hPL, and PlAP may reflect differences in the pathobiology of trophoblast in CHMs and PHMs and appear to be useful in the differential diagnosis of these conditions.

Abortion, Spontaneous↗
PubMed1987

Hydatidiform mole: parental chromosome aberrations in partial and complete moles.

The relationship between parental constitutional chromosome abnormalities and the development of hydatidiform mole was evaluated in series from four institutions. Karyotype analysis was performed on blood samples from 237 patients with a pathological diagnosis of complete mole and 217 of their spouses. One patient was found to have a constitutional balanced translocation, t(11;18), while one spouse was found to have a balanced translocation, t(4;20). Among 125 patients with partial mole and 106 of their spouses, one male was found to be a translocation carrier, t(13;14). No significant increase in the frequency of translocations in the parents of complete moles was found in any of the series considered separately or together. Data from the combined series show no evidence of constitutional parental chromosome aberrations as an aetiological factor in the development of molar pregnancies.

Chromosome Aberrations↗
PubMed1986

Tetraploid partial hydatidiform moles: two cases with a triple paternal contribution and a 92,XXXY karyotype.

In the course of a systematic study of cytogenetics, morphology, and clinical follow-up of hydatidiform moles we encountered two unusual cases of partial hydatidiform moles each with a 92,XXXY karyotype. Previously reported cases of tetraploidy, of 92,XXXX or 92,XXYY karyotype, resulted from a failure of the first mitotic division of a normal zygote. This is to our knowledge the first report of tetraploidy with XXXY sex chromosomes. Study of chromosomal heteromorphisms, isozymes, and restriction fragment length polymorphisms reveal that both present cases resulted from a combination of a haploid ovum with three haploid sets of paternal chromosomes either by the mechanism of trispermy (involving three separate haploid spermatozoa) or through dispermy (involving one haploid and one diploid sperm). Both cases resembled closely partial moles in their morphology; one gave a highly typical clinical picture while the other was recognized at an early voluntary abortion. Partial moles are ordinarily triploids of nearly always diandric constitution that evince focal villous swelling with cistern formation and focal trophoblastic hyperplasia. The findings here presented point to an association of molar phenotype with an excess of paternal over maternal haploid sets.

Adolescent↗
PubMed1985

Effect of hydatidiform molar vesicular fluid on blood coagulation.

The effect of fluids from both complete and partial hydatidiform moles on blood coagulation was determined. Coagulation was evaluated with use of the one-stage prothrombin time and the activated partial thromboplastin time. These studies demonstrated that the fluids shortened the activated partial thromboplastin time but not the prothrombin time. The use of plasmas deficient in factors V, VIII, IX, and X as substrate showed that the fluids shortened the activated partial thromboplastin time in the presence of plasmas deficient in factors VIII and IX but had no effect on the activated partial thromboplastin time in the presence of plasmas deficient in factors V and X. These data suggest that hydatidiform mole fluids possess procoagulant activity and that the activation of blood coagulation takes place at the level of factor X. These findings may have relevance to the placental and decidual focal necrosis seen in molar pregnancies, especially those of the complete variety.

Amniotic Fluid↗
PubMed1984

Human chorionic gonadotropin levels in complete and partial hydatidiform moles and in nonmolar abortuses.

The rates of regression of human chorionic gonadotropin (hCG) in patients with complete hydatidiform moles, partial hydatidiform moles, and nonmolar abortions were compared. No difference in rates of regression was found among the three groups, but levels of hCG immediately after uterine evacuation were significantly higher in the group with complete hydatidiform moles. Differences in the time required for hCG levels to become undetectable were attributed to the difference in the degree of initial elevation of hCG.

Abortion, Spontaneous↗
PubMed1983

Morphologic anomalies in triploid liveborn fetuses.

Analysis of the morphologic features of 43 complete and 11 mosaic triploid infants delivered at or after 22 weeks of gestation revealed, in addition to well-delineated gross features, a number of new or previously little emphasized histopathologic features. These included testicular Leydig cell hyperplasia, increased levels of hematopoiesis, and ovarian, adrenal, and pulmonary hypoplasia. Some of these findings appeared to be linked to partial hydatidiform mole replacing the normal placenta, which was present in about 70 per cent of the triploid cases. It is important to recognize the breadth of the triploidy spectrum, which ranges from near normalcy to multisystem involvement, and to pay special attention to the placenta. The importance of correct morphologic diagnosis of triploidy is stressed in view of the fact that its occurrence apparently does not prejudice the future reproductive performance of the parents.

Adolescent↗