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Changes of HCO3-/Cl- exchanger activity during meiotic maturation in Balb/c strain mouse oocytes and zygotes.

Intracellular pH-regulatory mechanisms are acquired by growing mouse oocytes with meiotic competence, and these mechanisms become fully active when the oocytes develop to the germinal vesicle (GV) stage as shown in CF1 and Balb/c strains mice. On the other hand, there is some evidence showing that intracellular pH-regulatory mechanisms are inhibited at the stages of Metaphase I (MI) and II (MII) oocytes in the CF1 strain mouse and hamster. Since it has been shown that the intracellular pH regulatory mechanism can be functionally different among mouse strains (e.g., CF1, Balb/c), the aim of thi…

Identification and characterization of an Xp22.33;Yp11.2 translocation causing a triplication of several genes of the pseudoautosomal region 1 in an XX male patient with severe systemic lupus erythematosus.

The X;Y translocation break point sequence in an XX male patient with prepubertal systemic lupus erythematosus (SLE) was characterized with the intention of identifying a predisposing gene(s) for SLE. Spectral karyotyping of the patient's metaphase chromosomes showed normal autosomes and 2 X chromosomes, one of which displayed a small portion of the Y chromosome. Using a Y chromosome polymerase chain reaction (PCR) walking strategy and inverse PCR, we found that the abnormal recombination occurred between retroviral long terminal repeats located at Xp22.33 (position 0.95 Mb; inside the pseudoa…

Additional Cyclin D(1) gene copies associated with chromosome 11 aberrations in cutaneous malignant melanoma.

Cyclin D1 (CCND1, PRAD1, bcl-1) is associated with progression through G1 and entry into S phase of the cell cycle, as a partner of cyclin-dependent kinases (CDKs). The aim of this study was to evaluate cytogenetic aberrations of the gene locus at chromosome 11q13 in cutaneous malignant melanoma. Fluorescence in situ hybridisation (FISH) was applied on metaphase spreads of short-term primary cell cultures as well as on 5 microm paraffin tissue sections of primary melanomas and melanoma metastases, and on melanoma cell lines (C32, WM 266-4, HT 144, RPMI 7951, SK MEL 28). For FISH analysis DNA p…

Cytogenetic aberrations in perineurioma: variation with subtype.

Only two karyotypes of perineurioma have previously been reported, 46XX,del(10)(q22q24),der(10),del(22)(q11-12q?)/47, idem,+der(10) (in a sc … add(2)(q11.2),add(3)(q12); and the abdominal soft tissue perineurioma showed 46,XX,t(8;9)(q13;q22). Metaphase FISH analysis for an ALK gene rearrangement in the sclerosing perineurioma with t(2;10) was negative; the ALK signal remained on the der(2). We conclude that perineuriomas display mostly simple karyotypes, characterized by one or few chromosomal rea …

AML1 gene over-expression in childhood acute lymphoblastic leukemia.

The present study was conducted on a series of 41 Egyptian children with newly diagnosed acute lymphoblastic leukemia (ALL) to investigate T … whereas in the remaining four cases they were due to tandem AML1 copies on der(21), as evidenced by metaphase FISH. Unexpectedly however, enhanced AML1 expression levels were seen by real-time quantitative RT-PCR in 18 out of the 41 ALL patients (43.9%). This high level of AML1 expression could be an important factor contributing to the pathogenesis and pro …

Production of nuclear transfer horse embryos by Piezo-driven injection of somatic cell nuclei and activation with stallion sperm cytosolic extract.

We investigated the use of direct nuclear injection using the Piezo drill and activation by injection of stallion sperm cytosolic extract for production of cloned equine embryos. When metaphase II horse oocytes were injected with either of two dosages of sperm extract and cultured 20 h, similar activation rates (88% vs. 90%) and cleavage rates (49% vs. 46%) were obtained. The successful reconstruction rate of horse oocytes with horse somatic cell donor nuclei after direct injection using the Piezo drill was 82%. Four dosages of sperm extract (containing 59, 176, 293, or 1375 microg/ml protein)…

Abnormal nuclear shape in solid tumors reflects mitotic instability.

Abnormalities in nuclear morphology are frequently observed in malignant tissues but the mechanisms behind these phenomena are still poorly understood. In this study, the relation between abnormal nuclear shape and chromosomal instability was explored in short-term tumor cell cultures. Mitotically unstable ring and dicentric chromosomes were identified by fluorescence in situ hybridization at metaphase and subsequently localized in interphase nuclei from five malignant soft tissue tumors. The vast majority (71 to 86%) of nuclear blebs, chromatin strings, and micronuclei contained material from…

Characterization of a highly complex region in Xq13 and mapping of three isodicentric breakpoints associated with preleukemia.

The chromosomal abnormality represented by an isodicentric X chromosome [idic(X)(q13)] is associated with a subset of acute myeloid leukemia … icated in isodicentric chromosome formation and other Xq13 chromosome aberrations. FISH analysis of metaphase chromosomes from two previously unpublished AML patients and one preleukemic patient using cosmid clones and selected subclones allowed mapping of the idic(X)(q13) breakpoints to a 100-kb interval, consistent with the involvement of an X-linked gene …

Detection of inv(16) and t(16;16) by fluorescence in situ hybridization in acute myeloid leukemia M4Eo.

BACKGROUND AND OBJECTIVE: It has been established that cytogenetic findings at the time of diagnosis of acute myeloid leukemia (AML) are powerful prognostic indicators. Pericentric inversion of chromosome 16 and translocation t(16;16) resulting in chimeric fusion of CBFB and MYH11 genes are typically seen in the M4-Eo FAB classification subset of AML and are associated with low-risk disease. These subtle chromosomal abnormalities may be difficult to detect in poor-quality metaphase preparations and if missed could lead to incorrect assignment to risk groups and influence the therapy decision-m…

Cytogenetic diagnosis of fragile X syndrome: study of 305 suspected cases in Saudi Arabia.

BACKGROUND: Fragile X syndrome is the most common cause of inherited mental retardation. Patients with fragile X syndrome show variable mental disability, typical long and narrow facial appearance with large ears and prominent fontanelle and frequent macro-orchidism. It is generally associated with a fragile site at Xq 27.3, which can be observed in the metaphase chromosome following selective culture conditions. At the molecular level, the fragile X syndrome is associated with an amplification of CGG repeat sequence of the FMR1 gene. The prevalence estimates are reported as one per 1500 males…

Symmetric replication of an unstable isodicentric Xq chromosome derived from isolocal maternal sister chromatid recombination.

An amniocyte culture was found to be mosaic for 45,X/46,X, idic(X)(p11.2)/ 47,X, idic(X)(p11.2),idic(X)(p11.2) cell lines, reflecting mitotic nondisjunction of the idic(X)(p11.2) chromosome. Upon learning of abnormal karyotype and ultrasound findings, the parents decided to discontinue the pregnancy. Subsequent cultures of fetal skin, kidney, and lung were mosaic 45,X/46,X,idic(X)(p11.2) reflecting mitotic loss of the unstable idic(X)(p11.2) chromosome. C-banding and in situ hybridization of X chromosome-specific alpha-satellite probe to metaphase fetal cells confirmed two centromeres on the i…

Разработка мини-герпесвируса в качестве общей стратегии по доведению до 180 кБ функциональных самовоспроизводящих мини-хромосом человека.

Для разработки терапевтических искусственных хромосом для человека (HAEC) требуется разработка стратегий, позволяющих получить большую функциональную самовоспроизводящуюся экстрахромосомную ДНК в целевых клетках. Члены герпесвильского семейства относятся к числу самых крупных эписомальных двухструнных вирусов ДНК. В качестве образцовых систем этого семейства эндемических инфекционных агентов были построены векторы, полученные из вируса 4 Epstein-Barr (EBV), которые перевели до 180 кБ ДНК, упакованных как инфекционные вироны. Такая стратегия трансдукции основывалась на некогенном мини-ЭБВ, имею

Совпадение в аннотации оригинала
The engineering of therapeutic human artificial episomal chromosomes, HAECs, requires the development of strategies to deliver large functio … es. Direct visualization of the therapeutic mini-EBV by fluorescent in situ hybridization (FISH) on metaphase and interphase nuclei indicated that 99% (556/563) of the transduced mini-EBV DNA was episomal with an average copy number of one to two per nucleus. This system should allow the delivery of large genes in common diseases such as hemophilia A and co …

Multicolor FISH mapping of YAC clones in 3p14 and identification of a YAC spanning both FRA3B and the t(3;8) associated with hereditary renal cell carcinoma.

Human chromosome band 3p14 contains two tightly linked cytogenetic markers of broad interest, FRA3B and the t(3;8) breakpoint associated wit … he t(3;8) breakpoint, we have used multicolor fluorescence in situ hybridization analysis (FISH) on metaphase spreads and interphase nuclei to order 14 yeast artificial chromosomes (YACs) in 3p14. The YACs used in this study were identified by a group of unordered lambda clones that had been previously localized to the 3p14 region and mapped proximal or dis …

Structural analysis of alpha-satellite DNA and centromere proteins using extended chromatin and chromosomes.

Human centromeres are characterized by distinct subsets of alpha-satellite DNA and by a number of centromeric proteins (CENPs) at least one of which, CENP-B, binds specifically to alpha-satellite DNA sequences. When the centromeres of metaphase chromosomes are mechanically stretched to five to 20 times their normal length, CENPs specifically recognized by CREST autoantibodies extend over the entire length of the linear alpha-satellite array. For higher resolution analysis we spread interphase chromatin across a slide resulting in highly extended chromatin fibers. By fluorescence in situ hybrid…

The development of chromosome-specific composite DNA probes for the mouse and their application to chromosome painting.

The speed and ease of human cytogenetic analysis has been greatly enhanced by the technique of fluorescence in situ hybridization (FISH). Non-radioactive fluorescently tagged complex DNA probes specific for individual chromosomes can be hybridized to conventionally obtained metaphase chromosome spreads. Several chromosomes may be "painted" concurrently by using combinations of different labeled probes. Surveys of chromosome breakage and rearrangement may be performed very quickly by avoiding the time consuming process of GTG-banding. The application of FISH to mouse cytogenetics would allow la…

Effect of sustained serum prolactin elevation on breast epithelial and myoepithelial cell proliferation.

Oral administration of the dopamine antagonist perphenazine (0.01% in drinking water) to adult female Sprague-Dawley rats led to a three- to fourfold increase in serum prolactin by the first time point sampled (day 2) and a sustained fourfold elevation from day 4 of treatment to the end of the experiment (day 54). In response, five- to sixfold (day 7) and three- to fourfold (day 4) peak elevations in the epithelial cell metaphase indices were seen in the breast lobular and ductular compartments respectively. Both indices fell to basal levels on day 14 but returned to a second, but diminished, …

[Repair of chromosomal aberrations in a human peripheral blood lymphocyte system after single and split-dose x-irradiation].

Whole human peripheral blood was exposed either acutely to 125 or 250 R X-rays or in fractions to 125+125 R X-rays at varying cell cycle times, namely, 0, 2, 4, 6, 8, 12, 16, 24, 30, 40 or 45 hours after culture initiation. Well spread metaphase chromosomes were examined for the following types of structural chromosome aberrations: dicentrics, rings, interstitial deletions, symetrical translocations, chromatid and chromosome fragments. Most noteworthy were found to be the polycentric + ring data. With acute radiation given at any of the times over the presynthetic period, the yields of these a…

Altered gene expression profile in cumulus cells of mature MII oocytes from patients with polycystic ovary syndrome.

STUDY QUESTION: Oocyte developmental competence is altered in patients with polycystic ovary syndrome (PCOS); is gene expression in cumulus cells (CCs) from mature metaphase II oocytes of patients with PCOS altered as well? SUMMARY ANSWER: Compared with CCs from non-PCOS patients, the gene expression profile of CCs isolated from mature oocytes of patients with PCOS present alterations that could explain the abnormal folliculogenesis and reduced oocyte competence in such patients. WHAT IS KNOWN ALREADY: Abnormal mRNA expression of several members of the insulin-like growth factor (IGF) family…

Fluorescent in situ hybridization and cytogenetic studies of trisomy 12 in chronic lymphocytic leukemia.

Cytogenetic studies (CG) of 475 chronic lymphocytic leukemia (CLL) cases showed trisomy 12 in 6.1% or 26% of patients with abnormal karyotypes. Fluorescence in situ hybridization (FISH) detected trisomy 12 in 35% of 117 CLL patients. Only 34.6% of cases detected by FISH were detected by CG. Twelve patients had low levels of trisomic cells (4% to 11%) relative to clonal B cells (47.5% to 86%), suggestive of clonal evolution. Untreated patients with trisomy 12 were predominantly male (P < .05) and had an increased incidence of splenomegaly (P < .03). Patients with trisomy 12 were more likely to

Abnormal chromosomes in histocytic lymphoma.

Five of six diffuse histocytic lymphoma patients had chromosomal abnormalities. Four had abnormal clones; three, a large acrocentric chromosome (LAC); and one, an abnormal large submetacentric chromosome (LSC). The LAC was a 14q+ and the LSC, a 4q+. Although no cytogenetic abnormality was found in a normal lymph node of a patient whose diseased lymph node had an LAC, abnormal chromosomes were seen in three patients with normal morphological bone marrow and in two peripheral blood specimens with a normal differential count. Since staging is important in aiding the clinician to select the type o