Frequency of aneuploidy in in vitro–matured MII oocytes and corresponding first polar bodies in two dairy cattle (Bos taurus) breeds as determined by dual-color fluorescent in situ hybridization

Vibrio parahaemolyticus is a human food-borne pathogen with the ability to enter the food chain. It is able to acquire a viable, non-cultivable state (VBNC), which is not detected by traditional methods. The combination of the direct viable count method and a fluorescent in situ hybridization technique (DVC-FISH) makes it possible to detect microorganisms that can present VBNC forms in complex samples The optimization of the in vitro DVC-FISH technique for V. parahaemolyticus was carried out. The selected antibiotic was ciprofloxacin at a concentration of 0.75 μg/mL with an incubation time in DVC broth of 5 h. The DVC-FISH technique and the traditional plate culture were applied to detect and quantify the viable cells of the affected pathogen in artificially contaminated food matrices at different temperatures. The results obtained showed that low temperatures produced an important logarithmic decrease of V. parahaemolyticus, while at 22 °C, it proliferated rapidly. The DVC-FISH technique proved to be a useful tool for the detection and quantification of V. parahaemolyticus in the two seafood matrices of oysters and mussels. This is the first study in which this technique has been developed to detect viable cells for this microorganism.

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Chromatin Quality as a Crucial Factor for the Success of Fluorescent in Situ Hybridization Analyses of Unfertilized Oocytes, Polar Bodies and Arrested Zygotes

Balkan Journal of Medical Genetics ◽

10.2478/v10034-010-0012-x ◽

2010 ◽

Vol 13 (1) ◽

pp. 1-8

Author(s):

R Zhivkova ◽

S Delimitreva ◽

D Toncheva ◽

I Vatev

Keyword(s):

Fluorescent In Situ Hybridization ◽

Sperm Chromatin ◽

Fish Analysis ◽

Premature Chromosome Condensation ◽

Related Research ◽

The Third ◽

Polar Bodies ◽

Cell Fixation

Chromatin Quality as a Crucial Factor for the Success of Fluorescent in Situ Hybridization Analyses of Unfertilized Oocytes, Polar Bodies and Arrested ZygotesMaterial that is supernumerary or unsuitable for in vitro fertilization (IVF) procedures is used for basic and for IVF-related research. Despite the disadvantages of such cells, they have contributed much to our understanding of the mechanisms and prevalence of different abnormalities.Fifty-four human unfertilized oocytes, 34 arrested bipronuclear zygotes and 15 polar bodies were fixed for analysis on the third day after in vitro insemination and were subjected to fluorescent in situ hybridization (FISH) with probes for chromosomes 18, 21, X and Y (centromere for 18, X, Y and locus-specific for 21). The aim of the study was the comparison of FISH efficiency in differently condensed chromatin.The success of FISH analysis was over 60% of analyzed cells and it was dependent on the chromatin changes (condensation and/or fragmentation) during the culture period before cell fixation. Chromatin ageing was the crucial factor for the reduced success of FISH in both oocyte chromosomes (60.0%) and pronuclei (61.76%). The chromatin of second polar bodies (PBII), and premature chromosome condensation (PCC) of the sperm chromatin in oocytes was more suitable for FISH analysis (FISH success 75.0% in PBII and 64.29% in PCC) with both centromere and locus-specific probes.These results revealed the significance of early signs of in vitro cell ageing for the success of FISH analysis and for the interpretation of results in case of analysis of unfertilized human ova, polar bodies and arrested zygotes.

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