1/92. Maternal uniparental disomy of chromosome 21 in a normal child.Maternal uniparental disomy of chromosome 21 [upd(21)mat] was found previously in a normal female and in 2 cases of early embryonic failure. We present a phenotypically normal child with upd(21)mat due to a de novo der(21;21)(q10;10). This finding suggests that chromosome 21 is not imprinted in the maternal germline.- - - - - - - - - - ranking = 1keywords = embryo (Clic here for more details about this article) |
2/92. Embryonal rhabdomyosarcoma with only numerical chromosome changes. Case report and review of the literature.An embryonal rhabdomyosarcoma, presenting as a retroperitoneal mass in a 15-year-old girl, is reported. The histological and immunohistochemical picture was typical, except for the presence of focal chondroid differentiation. Interestingly, expression of the "muscle markers" desmin and alpha-sarcomeric actin was present in the latter areas. cytogenetic analysis showed a hyperdiploid karyotype without structural chromosome changes. The pertinent literature on the subject is reviewed. Hyperdiploidy of the clonal type seems to occur frequently, but no characteristic karyotype is so far emerging.- - - - - - - - - - ranking = 1keywords = embryo (Clic here for more details about this article) |
3/92. trisomy/tetrasomy 21 mosaicism in CVS: interpretation of cytogenetic discrepancies between placental and fetal chromosome complements.trisomy/tetrasomy 21 mosaicism was found in chorionic villi (semidirect preparation) obtained from a 40 year old pregnant woman. Since both cell lines were abnormal, the couple elected for pregnancy termination. placenta and fetal tissue samples were obtained for cytogenetic study. Long term cultured villi showed a non-mosaic trisomy 21 karyotype, while other tissues showed either a normal karyotype or normal/trisomy21 mosaicism. These discrepancies could be explained by a modified "bottle neck" embryogenic model with a trisomic zygote and a non-disjunction event taking place in one of the first divisions. Our case emphasises the need for confirmatory studies in other tissues when mosaicism is encountered in chorionic villi, even if all cell lines are abnormal.- - - - - - - - - - ranking = 1keywords = embryo (Clic here for more details about this article) |
4/92. Maternal uniparental isodisomy for chromosome 14 detected prenatally.Maternal uniparental disomy (UPD) for chromosome 14 (upd(14)mat) has been associated with a distinct phenotype. We describe the first case of maternal uniparental isodisomy for chromosome 14 detected prenatally, in a pregnancy with mosaicism for trisomy 14 observed in both a chorionic villus sample (CVS) and in amniocytes. Detailed analysis of polymorphic microsatellites showed that the fetus was essentially isodisomic for one of the mother's chromosomes 14 and that recombination had introduced a mid-long arm region of heterodisomy. The fetus, which died in utero at 18 weeks, showed no apparent pathological features. The case demonstrates for the first time a maternal meiosis II non-disjunction of chromosome 14 leading to a trisomic conception which has been incompletely corrected by 'rescue' in the early embryo.- - - - - - - - - - ranking = 1keywords = embryo (Clic here for more details about this article) |
5/92. Patient with a 22q11.2 deletion with no overlap of the minimal digeorge syndrome critical region (MDGCR).The apparent lack of genotype/phenotype correlation in patients with the DiGeorge anomaly and velocardiofacial syndrome (DGA/VCFS; the "22q11 deletion syndrome") indicates a complex genetic condition. Most cases, whatever the phenotype, have a 1.5-3 Mb chromosomal deletion that includes the minimal DiGeorge critical region (MDGCR). Another potential critical region on 22q11 has been suggested based on two patients with distal deletions outside the MDGCR. We report on a patient with a VCFS phenotype who has a deletion, mapped by short tandem repeat polymorphic loci and fluorescence in situ hybridization analysis, distal to and not overlapping the MDGCR. This patient is deleted for several genes, including the T-box 1 gene (TBX1; a transcription regulator expressed early in embryogenesis) and catechol-O-methyltransferase (COMT; involved in neurotransmitter metabolism). We discuss the role these two genes may play in the clinical phenotype of the patient.- - - - - - - - - - ranking = 1keywords = embryo (Clic here for more details about this article) |
6/92. Karyotypic analyses of hepatoblastoma. Report of two cases and review of the literature suggesting chromosomal loci responsible for the pathogenesis of this disease.Two cases of fetal hepatoblastoma with unique karyotypic changes are described. One was a 17-month-old boy with multiple unbalanced chromosomal translocations, resulting in four types of derivative chromosomes involving chromosomal loci at 1q21, 1q32, 2q23, 6q27, 7p22, and 21p12, partial tetrasomy of 1q, partial trisomy of 2q, and partial monosomy of 21p. The clonal karyotype of this tumor was 46,XY,der(2)t(1;2)(q32;q37), der(6)t(1;6)(q12;q27), der(7)t(2;7)(q23;p22), der(21)t(2;21) (q23;p12). In the other case, a 4-year-old girl, karyotypic analyses revealed trisomy 2 and 8, and the clonal karyotype of this case was 48,XX, 2, 8. review of these cases together with previous reports suggested the significance of chromosomal changes including numerical abnormalities of 1q, 2(or 2q), 20, and 8 (or 8q), and breakage of 1q and 2q in the development of hepatoblastoma. The results presented herein underscore the significance of numerical abnormalities of chromosomal regions 1q and 2q and of chromosome 8 in the development of hepatoblastoma, in addition to abnormalities of 6q27, 7p22, and 21p12-13 as other chromosomal loci that may be responsible for the pathogenesis of this embryonal type of tumor.- - - - - - - - - - ranking = 1keywords = embryo (Clic here for more details about this article) |
7/92. Sperm quality may adversely affect the chromosome constitution of embryos that result from intracytoplasmic sperm injection.OBJECTIVE: To determine whether the high rate of chromosomal abnormalities in the embryos of an infertile couple were caused by a paternal factor that may have involved the sperm centriole. DESIGN: Case report. SETTING: Private IVF program. PATIENT(S): An infertile couple who underwent IVF-ET because of severe male factor infertility and endometriosis. INTERVENTION(S): Preimplantation genetic diagnosis of chromosomal abnormalities in embryos derived from two cycles of ICSI in which the husband's sperm was used and one in which donor sperm was used. MAIN OUTCOME MEASURE(S): Preimplantation genetic diagnosis with fluorescence in situ hybridization using probes for chromosomes X, Y, 13, 16, 18, and 21, and determination of hCG levels. RESULT(S): Most of the embryos derived from the cycles in which the husband's sperm was used were chromosomally abnormal (82%), whereas all the embryos derived from the cycle in which donor sperm was used were chromosomally normal. The cycle in which donor sperm was used resulted in an ongoing pregnancy. CONCLUSION(S): Paternal factors, which most likely derive from the centrosome, can contribute to numerical chromosomal abnormalities, which in turn may predispose to implantation failure.- - - - - - - - - - ranking = 8keywords = embryo (Clic here for more details about this article) |
8/92. Solid and cystic tumor of the pancreas: clinicopathologic and genetic studies of four cases.BACKGROUND: Solid and cystic tumor (SCT) of the pancreas can be distinguished from other pancreatic neoplasms by its nearly exclusive occurrence in young women, and its favorable prognosis after complete resection. methods: We experienced four cases with SCT of the pancreas, and analyzed these tumors by immunohistochemical and electron microscopic studies, as well as genetic analysis of ras oncogene mutation. RESULTS: The presented cases expressed the neuron-specific enolase in two cases, alpha1-antitrypsin and alpha1-antichymotrypsin in two cases, and vimentin in one case, which indicated that this tumor originates from pleuripotential embryonic stem cells. No patients had mutations of K-ras gene in codon 12, and further genetic analysis is required to predict the malignant potential. CONCLUSION: SCT of the pancreas appears to have limited malignant potential and the metastatic ratio is not high, although the tumor has local invasion. Therefore, an aggressive surgical approach seems fully justified.- - - - - - - - - - ranking = 1keywords = embryo (Clic here for more details about this article) |
9/92. A new human pleomorphic rhabdomyosarcoma cell-line, HS-RMS-1, exhibiting MyoD1 and myogenin.A number of human cell lines derived from alveolar or embryonal rhabdomyosarcoma (RMS) have been described. To our knowledge, however, no cell line established from pleomorphic RMS has been reported. We describe here the establishment and characterization of a new human cell line, HS-RMS-1, which originated from a typical pleomorphic RMS arising in the gluteal muscle of a 26-year-old man. HS-RMS-1 cells had pseudotetraploid complex karyotypes with no specific abnormalities. Both in vitro and in vivo the cells on light microscopic examination exhibited pleomorphic features with immunopositive reaction for myogenic antigens including MyoD1 and myogenin, although no Z band-like structures were detected electron-microscopically. RT-PCR demonstrated the expression of MyoD1 and myogenin in HS-RMS-1 cells at the mRNA level, and direct sequencing analysis revealed cDNAs of MyoD1 and myogenin identical to those previously reported. This cell line, HS-RMS-1, established from pleomophic RMS will be useful for further studies including the molecular aspects of human RMS.- - - - - - - - - - ranking = 1keywords = embryo (Clic here for more details about this article) |
10/92. Outcome of preimplantation genetic diagnosis of translocations.OBJECTIVE: To review 35 cases of preimplantation genetic diagnosis (PGD) of translocations with several methods, including telomeric probes. DESIGN: Retrospective study. SETTING: Clinical IVF laboratory. PATIENT(s): Thirty-five couples with one partner carrying a chromosomal translocation. INTERVENTION(s): PGD of translocation after polar-body or embryo biopsy. MAIN OUTCOME MEASURE(s): pregnancy outcome. RESULT(s): Several trends were observed. First, PGD can achieve a statistically significant reduction in spontaneous abortion, from 95% to 13%. Second, the chances of achieving pregnancy are correlated with 50% or more of the embryos being chromosomally normal. Third, patients with robertsonian translocations produced fewer abnormal gametes and more pregnancies than did patients with reciprocal translocations. Fourth, a new fluorescence in situ hybridization protocol for PGD of translocations, which involves applying telomeric probes, has proved adequately reliable with a 6% average error rate. CONCLUSION(s): PGD of translocations achieves a statistically significant reduction in spontaneous abortion, both for polar-body and blastomere biopsy cases. pregnancy outcome depended on the number of normal embryos available for transfer, with patients having <50% abnormal embryos achieving the most pregnancies. Because robertsonian translocations caused fewer abnormal embryos than reciprocal translocations, they also resulted in higher rates of implantation.- - - - - - - - - - ranking = 117.15063070094keywords = preimplantation, embryo (Clic here for more details about this article) |
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