Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0029713 (immaturity)
 4,335 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Cytogenetic analysis of bone marrow cells of a 63-year-old male Caucasian patient with polycythemia vera (PV) who developed anemia, thrombocytopenia, and increased granulocytic immaturity revealed a 47, X,der(Y) t(Y;1)(q12;q12),+9 karyotype. The breakpoint in chromosome 1 appeared to map to q12 and not to q21, as has been described in previous reports without FISH confirmation. In the 4 years before this transition the patient was polycythemic and, accordingly, treated with phlebotomy and three short courses of busulfan. The cytogenetic picture observed has been described before in seven patients: three with PV, three with myelodysplasia, and one with Fanconi anemia. In 5/7 cases, like in our patient, the abnormality was observed during transition of the disease into either myelodysplasia or AML.
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PMID:Derivative (y)t(Y;1)(q12;q12),+9 in a patient with polycythemia vera during transition into myelodysplasia. 863 Sep 87

We examined cytological and cytogenetic parameters of 1076 oocytes and 385 zygotes that failed to develop post in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI). Out of 1076 oocytes, 894 (83%) arrested oocytes showed a first polar body and were thus assumed arrested at metaphase II while the remainder showed no polar body. In the group of oocytes with a polar body, 20.5% had an abnormal karyotype. Cytologically, premature sperm chromosome condensation was noted in 28.3% of uncleaved oocytes. This high PCC can be explained by the different grades of oocyte maturity from one center to another. Oocytes from older women showed no increased aneuploidy but did show increased premature chromosome condensation. Analysis by classical technique of 220 uncleaved zygotes showed 91 with highly condensed chromosomes, 53 with asynchrony of condensation, 31 with pulverized chromosomes, and 45 arrested at the first somatic metaphase. Out of 385 arrested zygotes, 165 were explored by in situ hybridization. FISH using a set of 7 chromosome-specific probes showed aneuploidy in the chromosomes analyzed (13, 16, 18, 21, 22, X, Y) in 21.8% of blocked zygotes (19-25% depending on morphology). Extrapolating to other chromosomes, we expect that a vast majority of blocked zygotes and oocytes probably carry chromosome abnormalities. These data demonstrate the contributions of chromosome disorder in early embryo development blocking and implantation failure. Certainly, the issue of cytoplasm and nuclear immaturity and their relation to each other and to chromosome abnormalities provides a fertile area for future investigation in ART.
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PMID:Morphological and cytogenetic analysis of intact oocytes and blocked zygotes. 1274 38

Chromosome number abnormalities are remarkably common in human reproduction. Most are caused by chromosomal non-disjunction and premature chromatid separation in oocyte meiosis I. Pooled data from previous studies showed that one in five oocytes that failed to fertilize after in vitro insemination was abnormal when analysed by conventional cytogenetics. Preconception genetic diagnosis, carried out on the first and second polar bodies by FISH, using 5 chromosome-specific probes (13, 16, 18, 21 and 22), showed that the rate of aneuploidy is higher in women aged 35 or over (52.1 per cent). Oocyte dysmorphy seems to have little effect on the rate of aneuploidy except for giant oocytes, which are usually diploid and may cause triploidy after fertilization. Intra- and extrafollicular influences (perifollicular microvasculature, oxygenation, the presence of residues from cigarette smoke) may disturb maturation, leading to immaturity and aneuploidy. Thus, oocyte meiosis is very sensitive to endogenous and exogenous factors that may cause the production of oocytes with chromosomal abnormalities and therefore, of abnormal zygotes.
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PMID:Genetic analysis of the oocyte--a review. 1455 33