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مرکز اطلاعات علمی SID1
اسکوپوس
دانشگاه غیر انتفاعی مهر اروند
ریسرچگیت
strs
Issue Info: 
  • Year: 

    2015
  • Volume: 

    9
  • Issue: 

    3
  • Pages: 

    346-353
Measures: 
  • Citations: 

    0
  • Views: 

    67692
  • Downloads: 

    64962
Abstract: 

Background: Selecting the best embryo for transfer, with the highest chance of achieving a vital pregnancy, is a major goal in current in vitro fertilization (IVF) technology. The high rate of embryonic developmental arrest during IVF treatment is one of the limitations in achieving this goal. CHROMOSOMAL abnormalities are possibly linked with CHROMOSOMAL arrest and selection against abnormal fertilization products. The objective of this study was to evaluate the frequency and type of CHROMOSOMAL abnormalities in preimplantation embryos with developmental arrest.Materials and Methods: This cohort study included blastomeres of embryos with early developmental arrest that were biopsied and analyzed by fluorescence in-situ hybridization (FISH) with probes for chromosomes 13, 16, 18, 21 and 22. Forty-five couples undergoing IVF treatment were included, and 119 arrested embryos were biopsied. All probes were obtained from the Kinderwunsch Zentrum, Linz, Austria, between August 2009 and August 2011.Results: Of these embryos, 31.6% were normal for all chromosomes tested, and 68.4% were abnormal. Eleven embryos were uniformly aneuploid, 20 were polyploid, 3 were haploid, 11 displayed mosaicism and 22 embryos exhibited chaotic CHROMOSOMAL complement. Conclusion: Nearly 70% of arrested embryos exhibit CHROMOSOMAL errors, making CHROMOSOMAL abnormalities a major cause of embryonic arrest and may be a further explanation for the high developmental failure rates during culture of the embryos in the IVF setting.

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Issue Info: 
  • Year: 

    2014
  • Volume: 

    8
  • Issue: 

    1
  • Pages: 

    35-42
Measures: 
  • Citations: 

    0
  • Views: 

    92218
  • Downloads: 

    108708
Abstract: 

Background: CHROMOSOMAL abnormalities and Y chromosome microdeletions are regarded as two most frequent genetic causes associated with failure of spermatogenesis in the Caucasian population.Materials and Methods: To investigate the distribution of genetic DEFECTS in the Romanian population with azoospermia or severe oligozoospermia, karyotype analysis by G-banding was carried out in 850 idiopathic infertile men and in 49 fertile men with one or more children. Screening for microdeletions in the azoospermia factor (AZF) region of Y chromosome was performed by multiplex polymerase chain reaction (PCR) on a group of 67 patients with no detectable CHROMOSOMAL abnormality. The results of the two groups were compared by a two-tailed Fisher’s exact test.Results: In our study CHROMOSOMAL abnormalities were observed in 12.70% and 8.16% of infertile and fertile individuals respectively.Conclusion: Our data suggests that infertile men with severe azoospermia have higher incidences of genetic DEFECTS than fertile men and also patients from any other group. Infertile men with normal sperm present a higher rate of polymorphic variants. It is important to know whether there is a genetic cause of male infertility before patients are subjected to intracytoplasmic sperm injection (ICSI) or testicular sperm extraction (TESE) /ICSI treatment.

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Journal: 

NATURE

Issue Info: 
  • Year: 

    2004
  • Volume: 

    428
  • Issue: 

    -
  • Pages: 

    77-81
Measures: 
  • Citations: 

    464
  • Views: 

    31748
  • Downloads: 

    29822
Keywords: 
Abstract: 

Yearly Impact:

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گارگاه ها آموزشی
Author(s): 

ANDERSON C.L. | BROWN C.E.

Issue Info: 
  • Year: 

    2009
  • Volume: 

    79
  • Issue: 

    2
  • Pages: 

    117-123
Measures: 
  • Citations: 

    466
  • Views: 

    22830
  • Downloads: 

    30210
Keywords: 
Abstract: 

Yearly Impact:

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Author(s): 

VISOOTSAK J. | GRAHAM J.M.JR.

Issue Info: 
  • Year: 

    2006
  • Volume: 

    1
  • Issue: 

    -
  • Pages: 

    0-0
Measures: 
  • Citations: 

    465
  • Views: 

    28794
  • Downloads: 

    30016
Keywords: 
Abstract: 

Yearly Impact:

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Issue Info: 
  • Year: 

    2012
  • Volume: 

    15
  • Issue: 

    4
  • Pages: 

    232-234
Measures: 
  • Citations: 

    0
  • Views: 

    118233
  • Downloads: 

    81718
Abstract: 

BACKGROUND: Secondary amenorrhea is a condition in which there is cessation of menses after at least one menstruation. It is a symptom of different diseases, such as hormonal disturbances which range from pituitary to ovarian origin, as well as CHROMOSOMAL abnormalities. Knowledge of the distinct cause of secondary amenorrhea is of tremendous benefit for the management and monitoring of patients. In this study, we determine the CHROMOSOMAL abnormalities in patients with secondary amenorrhea in Southwest Iran.METHODS: We selected 94 patients with secondary amenorrhea who referred to our Cytogenetic Ward from 2004 until 2009. For karyotyping, peripheral blood lymphocyte cultures were set up by conventional technique.RESULTS: In this study, 5.3% (n=5) of patients with secondary amenorrhea presented with CHROMOSOMAL abnormalities, of which all contained an X element. The CHROMOSOMAL abnormalities were:i) 45, X (n=1), ii) 47, XXX (n=1), iii) 45, X [13]/ 45, Xi(X)q[17] (n=1), iv) 45, X[12]/46,X,+mar[12] (n=1), and v) 46,X,del(Xq)(q23q28) (n=1).CONCLUSION: Our study revealed that some causes of secondary amenorrhea could be due to CHROMOSOMAL abnormalities. Therefore, cytogenetic studies should be important tests in the evaluation of patients with secondary amenorrhea.

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strs
Author(s): 

PELLESTOR F. | ANAHORY T.

Issue Info: 
  • Year: 

    2011
  • Volume: 

    17
  • Issue: 

    4
  • Pages: 

    476-494
Measures: 
  • Citations: 

    477
  • Views: 

    30437
  • Downloads: 

    32295
Keywords: 
Abstract: 

Yearly Impact:

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Author(s): 

AMINI F. | HEMATZADEH A.

Issue Info: 
  • Year: 

    2012
  • Volume: 

    67
  • Issue: 

    3
  • Pages: 

    291-296
Measures: 
  • Citations: 

    1
  • Views: 

    851
  • Downloads: 

    243
Abstract: 

BACKGROUND: Zagros Pupfish (Aphanius vladykovi) is a native fish of Iran which is found in basins of Chahar Mahal & Bakhtiari province. OBJECTIVES: In this study, the chromosome number and karyotype of Zagros Pupfish were investigated. METHODS: To obtain metaphase chromosome spreadsin vivo, 1.2-5.4 g fish were injected intraperitoneally by 0.1-0.15 mg/g of 1% colchicine and were humanely killed after being incubated in a well-aerated tank for 4-5 hours at 22-23oC. Hematopoietic, testis or ovary, gill, spleen and liver tissues were isolated from the fish and were fixed with cold Carnoy's solution after being hypotonized in 0.075 M KCl. Chromosome spreads were prepared by either splashing of cell suspension or stamping of whole tissues onto slides. Slides were then stained by 10% Giemsa followed by microscopic observation. Suitable metaphase plates were digitally microphotographed and chromosomes were counted and karyotyped. RESULTS: Diploid chromosome number ranged from 42 to 49 with the modal number (2n) of 48. Based on the prepared karyotype, chromosome formula for this species was 12st+36 a/t and the number of chromosome arms (FN) was calculated 60. No heteromorphic sex chromosomes could be recognized in this species. CONCLUSIONS: The diploid chromosome number of Zagros Pupfish is similar to other species of the same genus so far investigated.

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Issue Info: 
  • Year: 

    2006
  • Volume: 

    16
  • Issue: 

    51
  • Pages: 

    43-50
Measures: 
  • Citations: 

    0
  • Views: 

    1257
  • Downloads: 

    508
Abstract: 

Background and purpose: It is clearly shown that ionising radiations induce various kinds of DNA damages majority of which as sub-lethal damages, are repaired but still some of them are left urepaired and lead to CHROMOSOMAL aberrations. These CHROMOSOMAL aberrations in radiation workers, who are occupationally exposed to radiation,could be assayed with cytogenetic evaluation methods.These cytogenetic assessments are good indicators for evaluating the health of radiation workers as well as radiation protection quality in medical radiation centers. The aim of the present study was to determine the frequency of the CHROMOSOMAL aberrations using analysis of metaphase amethod in radiation workers of radiology departments in Babol.Materials and methods: Heparinized venous blood samples were prepared from 62 radiology workers and 29 individuals as control population whose duties did not expose them to radiation sources. Lymphocytes were cultured in culture medium consisting of RPMI-1640 supplemented with L-glutamine, 15% fetal calf serum (FCS) and antibiotics. PHA at a concentration of 5 μg/ml was used to stimulate division of lymphocytes in culture. Blood cultures were incubated at 37°C for 48 hours and 2 hours prior to harvesting; colcemid was added to cultures at a final concentration of 0.1 μg/ml to arrest the dividing lymphocytes in mitosis. At hour 50 the cells were collected, washed and fixed on the slides followed by staining. One hundred mitoses were analyzed for each sample and CHROMOSOMAL aberrations were scored and statistically analyzed.Results: Results showed that the mean frequencies of the total CHROMOSOMAL aberrations in radiation workers is significantly higher than controls (p=0.014). It was also shown that there is no significant correlation between the frequency of CHROMOSOMAL aberration and age, sex and smoking of individuals in both groups. Also no significant correlation was noted between the frequency of CHROMOSOMAL aberrations in radiation workers and the years of work as well as history of over dose.Conclusion: The higher frequency of CHROMOSOMAL aberration in lymphocytes of radiation workers compared to non exposed controls is in full agreement with other reports and could be due to the accumulative effect of radiation induced initial DNA damage in individuals exposed to chronic and low doses of radiation which, finally leads to detectable CHROMOSOMAL aberrations. Results showed that the frequency of CHROMOSOMAL aberrations were age, sex and smoking independent and it was not also a function of years of work and unusual exposure. Regarding the controversy over this issue in the literature, further researches are needed to be done.

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Author(s): 

FAGHRI J. | SALEHI MANSOUR

Issue Info: 
  • Year: 

    2007
  • Volume: 

    25
  • Issue: 

    8 (SUPPLEMENT)
  • Pages: 

    6-9
Measures: 
  • Citations: 

    0
  • Views: 

    55359
  • Downloads: 

    30797
Abstract: 

Background: In all types of malignant lymphoma, non-random and significant CHROMOSOMAL abnormalities have been reported. Some studies clearly demonstrated that the karyotypic patterns are important prognostic factors in non-Hodgkin's lymphoma (NHL).Methods: Cytogenetic investigations were attempted on 21 biopsies from lymphomapatients. The samples were minced and cultured to produce metaphasic cells. Two cases did fail to produce metaphases and two others were reactive lymph nodes. The karyotypes of 15NHL biopsy samples were determined by G-banding method.Findings: By collecting data on numerical and structural CHROMOSOMAL changes, it was demonstrated that all chromosomes, except Y, were involved in numerical abnormalities. Most of the chromosomes, other than chromosomes 9, 10, 19 and Y, exhibited structural rearrangements.Complex rearrangements and unidentifiable markers were documented in most samples.Conclusion: Cytogenetic studies might contribute to an increased understanding of malignant lymphoma progression and may refine patient diagnosis.

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