Wyniki wyszukiwania - Biblioteka Nauki

1

Double aneuploidy with karyotype 48,XXY,+18 in first trimester fetus - case report

100%

Dudarewicz L. , Wysocka U. , Jakubowski L.

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tom 4

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nr 2

24-28

EN

Double anueploidy, involving both trisomy 18 and Klinefelter syndrome at the same time, is a rare event, in which the features of Edwards syndrome dominate the clinical picture. We describe a patient, who was diagnosed in the 8th gestational week with a seemingly normal intrauterine pregnancy with “chorionic bump”. In the 12th week the following abnormalities were diagnosed by ultrasound: Increased nuchal translucency (4.7 mm), increased anteroposterior diameter of the fourth ventricle and increased diameter of the third ventricle of the brain, mesocardia and cardiomegaly. The CVS karyotype revealed 48,XXY,+18 karyotype. In our opinion, the increased anteroposterior diameter of the fourth ventricle of the brain in this fetus was probably an early manifestation of the Dandy-Walker malformation (unproven because of early pregnancy termination), which is typical of Edwards syndrome fetuses. We consider the increased anteroposterior diameter of the fourth ventricle of the brain in the first trimester fetus as an indication for fetal karyotyping and further detailed imaging studies.

2

Rola aneuploidów i niektórych mutacji chromosomowych w praktycznej hodowli roślin zbożowych

88%

Nalepa S.

Zeszyty Problemowe Postępów Nauk Rolniczych

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1972

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tom 125

3

DNA aneuploidia in cells of acute leukemia non B non T type on children

88%

Krygier-Stojalowska A. , Zwierzykowska A. , Rakowska-Plusser M. , Urasinski T. , Osipowicz E. , Gapski Z. , Wozniak B.

Folia Histochemica et Cytobiologica

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1986

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tom 24

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nr 3

4

Cytogenetyka aneuploidalnych roślin Triticale 6x. Cz. I Aneuploidalność

88%

Gruszecka D.

Annales Universitatis Mariae Curie-Skłodowska. Sectio E. Agricultura

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1982

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tom 37

5

Studies on the influence of aneuploidy of spermatozoa obtained from patients with oligozoospermia on their structure

88%

Stecewicz D. , Warchol J. B.

Folia Histochemica et Cytobiologica

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2001

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tom 39

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nr 1

6

Cytogenetyka aneuploidalnych roślin Triticale 6x. Cz. II. Identyfikacja chromosomów

75%

Gruszecka D.

Annales Universitatis Mariae Curie-Skłodowska. Sectio E. Agricultura

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1982

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tom 37

7

Molecular methods for rapid detection of aneuploidy

75%

Dudarewicz L. , Holzgreve W. , Jeziorowska A. , Jakubowski L. , Zimmermann B.

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tom 46

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nr 2

EN

Rapid molecular biological methods for prenatal diagnosis of the most common aneuploidies, collectively known as rapid aneuploidy testing, are compared in this review. We discuss methodological problems and limitations of these various methods. All these techniques are believed to be accurate and carry a low risk of misdiagnosis, but they differ in terms of labour-intensity and amenability to automation and high throughput testing. The question how to apply them safely and economically in a clinical setting has not been answered yet. The discussed techniques are so far not used as stand-alone tests, but some of them are routinely applied as a preliminary test that shortens the waiting time for classic cytogenetic karyotyping. In the future, mainly because of economical reasons, these methods may replace cytogenetics in the category of patients who make up the majority of those currently offered prenatal karyotyping: patients with moderately increased risk and no abnormalities detected by ultrasound.

8

Influence of a heavy-metal-polluted environment on Viola tricolor genome size and chromosome number

63%

Slomka A. , Siwinska D. , Wolny E. , Kellner K. , Kuta E.

Acta Biologica Cracoviensia. Series Botanica

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2011

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tom 53

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nr 1

EN

Intraspecific changes in genome size and chromosome number lead to divergence and species evolution. Heavy metals disturb the cell cycle and cause mutations. Areas contaminated by heavy metals (metalliferous sites) are places where microevolutionary processes accelerate; very often only a few generations are enough for a new genotype to arise. This study, which continues our long-term research on Viola tricolor (Violaceae), a species occurring on both metalliferous (Zn, Pb, Cd, Cu) and non-metalliferous soils in Western and Central Europe, is aimed at determining the influence of environments polluted with heavy metals on genome size and karyological variability. The genome size of V. tricolor ranged from 3.801 to 4.203 pg, but the differences between metallicolous and non-metallicolous populations were not statistically significant. Altered chromosome numbers were significantly more frequent in material from the polluted sites than from the non-polluted sites (43% versus 28%). Besides the standard chromosome number (2n = 26), aneuploid cells with lower (2n = 18–25) or higher (2n = 27, 28) chromosome numbers were found in plants from both types of site, but polyploid (2n = 42) cells were observed only in plants from the metalliferous locality. The lack of correlation between chromosome variability in root meristematic cells and genome size estimated from peduncle cells can be attributed to elimination of somatic mutations in generative meristem, producing chromosome-stable non-meristematic tissues in the peduncle.

9

Reduced fertility and meiotic abnormalities in late generations of telomerase-deficient Arabidopsis thaliana

63%

Puizina J. , Samanic I.

Acta Biologica Cracoviensia. Series Botanica

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2013

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tom 55

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nr 1

EN

Here we report the consequences of telomere erosion in Arabidopsis thaliana, studied by examining seed and pollen production and the course of male meiosis through the last five generations (G5–G9) of telomerase-deficient Arabidopsis mutants. We used a previously described mutant line in which telomerase activity was abolished by T-DNA insertion into the TERT gene encoding telomerase reverse transcriptase. Reduced fertility accompanied by morphological abnormalities occurred in G6, which produced on average 35 seeds per silique (vs. 43 in wild type) and worsened in G7 (30 seeds) and G8 (14 seeds), as did the morphological abnormalities. The last generation of tert mutants (G9) did not form reproductive organs. Analysis of meiosis indicated that the main cause of reduced fertility in the late generation tert mutants of Arabidopsis was the numerous chromosomal end-to-end fusions which led to massive genome rearrangements in meiocytes. Fusion of meiotic chromosomes began in G5 and increased in each of the next generations. Unpaired chromosomes (univalents) were observed in G7 and G8. The study highlights some differences in the meiotic consequences of telomere shortening between plant and animal systems.

10

Aneuploids in the shrub birch Betula humilis populations in Poland

63%

Jadwiszczak K. , Jablonska E. , Klosowski S. , Banaszek A.

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2011

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tom 80

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nr 3

EN

Shrub birch (Betula humilis Schrk.) is endangered glacial relict growing in natural and drained fens and transitional mires. At present study we examined karyotypes of 103 individuals of B. humilis, collected in six populations from eastern and northeastern Poland. We found 60% of diploid individuals with 2n = 28. The rest of studied plants were aneuploids with 26, 27, 29, 30 and 31 chromosomes in their karyotypes. High frequencies of aneuploids in Polish populations of B. humilis could be a consequence of: (i) hybridization with congeneric species, (ii) stress resulting from range fragmentation, (iii) karyotype instability of individuals with 2n ≠ 28, or (iv) vegetative reproduction.

11

Karyology of the genus Agrostis [Poaceae] - a review

63%

Frey L.

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nr 2

12

Ciprofloxacin inhibits proliferation and promotes generation of aneuploidy in Jurkat cells

51%

Koziel R. , Szczepanowska J. , Magalska A. , Piwocka K. , Duszynski J. , Zablocki K.

Journal of Physiology and Pharmacology

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2010

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tom 61

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nr 2

EN

Ciprofloxacin is widely used in antimicrobial therapy. However it also inhibits mitochondrial topoisomerase II and therefore affects cellular energy metabolism. At a concentration exceeding 80 µg/ml ciprofloxacin induces apoptosis, while at 25 µg/ml it inhibits proliferation of Jurkat cells without any symptoms of cell death. The aim of this study was to explain the mechanisms of ciprofloxacin-evoked perturbations of the cell cycle. Human lymphoidal cells (Jurkat) were exposed to ciprofloxacin (25 µg/ml) for 4-11 days and effects of the drug on cell proliferation (light microscopy), cell cycle (flow cytometry), cell size and morphology (confocal microscopy) as well as number of chromosomes (chromosomal spread analysis) were investigated. Exposition of Jurkat cells to ciprofloxacin inhibited cell proliferation, increased proportion of cells in the G2/M-phase of the cell cycle, compromised formation of the mitotic spindle and induced aneuploidy. These observations indicate that ciprofloxacin applied at concentrations insufficient for induction of apoptosis may stop cell proliferation by inhibition of mitosis. Chromosomal instability of such cells may, at least potentially, increase a risk of cancer development.

13

Utilization of the probe generated by chromosome microdissection, for detection of equine X chromosome aneuploidy

51%

Bugno M. , Pienkowska-Schelling A. , Schelling C. , Wlodarczyk N. , Slota E.

Annals of Animal Science

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2006

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tom 06

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nr 2

14

Aneuploidy, chromosomal missegregation, and cell cycle reentry in Alzheimer's disease

51%

Zekanowski C. , Wojda U.

Acta Neurobiologiae Experimentalis

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2009

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tom 69

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nr 2

232-253

EN

Alzheimer's disease (AD) is a neurodegenerative disorder with a complex etiology and pathogenesis. Chromosome missegregation was proposed two decades ago to be responsible for neurodegeneration in AD patients. It was speculated that the aneuploidy is a result of aberrant cell cycle of neuronal progenitors during adult neurogenesis and/or of mature neurons. There is mounting evidence of increased rate of general aneuploidy and cell cycle reentry in the AD patients' brains, with area-specific pattern. In this review, we discuss the involvement of chromosome instability, genome damage and cell cycle impairment in AD pathology.

15

Cytological changes in tissue culture of Allium sibiricum L.

51%

Golczyk H.

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tom 36

EN

Cytological studies have been performed on Allium sibiricum L. callus culture. Interesting cytological changes observed during callus growth included polyploidy, aneuploidy and structural aberrations of chromosomes (ring-chromosomes, deletions, formation of dicentric and tricentric chromosomes). The rate of these changes increased with the time of culture.

16

Karyology of bryophytes

44%

Przywara L. , Kuta E.

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tom 09

17

Somaclonal selection of physiological mutants and several problems related to rice cell breeding

44%

Kinoshita T. , Mori K.

Journal of Applied Genetics

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1998

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tom 39

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nr 1

EN

Tolerance to a new herbicide, pyributycarb, was evaluated both at the plant and cellular levels. Several highly or moderately tolerant strains chosen at the plant level, showed a parallel relation of to tolerance at the cellular level. However, on the whole, correlation between total tolerance indices and survival rates of calli was not significant in 18 out of the 80 studied strains. As a result of somaclonal selection for two herbicides, lines NB-200 and NM-100 were regenerated from the tolerant calli screened with benthiocarb at 200 ppm, and molinate at 100 ppm, respectively. In the R₂ generation, both the lines displaned a stable tolerance both at the plant and cellular levels. Thus the highly tolerant mutant lines were developed from a moderately tolerant line, N-61, via in vitro selection. To achieve a short-cut method in the interspecific genetic exchange, a series of techniques related to cell fusion were established in rice and related species. Two kinds of somatic hybrids between the cultivar Kitaake and tetraploid Oryza species, O. punctata and O. officinalis, were successfully produced. Among the somatic hybrid plants, a wide range of chromosomal variation was observed. Aneuploid plants with a chromosome number around 2n = 72 (hexaploid), which are expected from a symmetric fusion between diploid and tetraploid strains, were obtained showing mixoploidy within a plant. Most of the somatic hybrids were characterized by intermediate features of plant-type showing high sterility, shattering of spikelets and reduced plant height. As an exception, a diploid plant, which was identified by RFLP analysis using the rDNA gene probe, closely resembled Kitaake and produced viable seeds. A tetraploid hybrid plant was also promising for the introduction of economically important characters through the reduction of chromosome numbers by doubled haploids. Gametoclonal variation and gamma radiation was applied to Kitaake. The mutation frequency was prominently increased by gamma ray treatment, especially at high doses of 200 Gy or 300 Gy. In the M₃R₂ or M₄R₃ generations, most of the variants showed unfavourable characters. Most of the mutant characters were governed by single or double recessive genes. Several mutants such as short culm and early flowering time might be used for rice breeding.