Avtor/Urednik		Kovačič, Borut
Naslov		Konfiguracija mikrotubulov in kromosomov v neoplojenih človeških jajčnih celicah po intracitoplazmatskem injiciranju semenčice
Prevedeni naslov		Configuration of microtubules and chromosomes in human oocytes failed to fertilize after intracytoplasmic sperm injection
Tip		monografija
Kraj izdaje		Ljubljana
Založnik		Medicinska fakulteta
Leto izdaje		1999
Obseg		str. 59
Jezik		slo
Abstrakt		The configuration of microtubules and chromosomes of 180 human oocytes failing to fertilize after intracytoplasmic sperm injection (ICSI) was observed in order to establish at which stages fertilization is most frequently arrested. In 134 (74%) unfertilized cells the injected sperms started to decondense chromatin, but in 53 (40%) cells the decondensation was arrested already after sperm swelling while in 51 (38%) cells the sperm chromosomes were decondensed prematurely (G1-PCC). The G1-PCC phenomenon was most often (in 85%) seen in unactivated oocytes. In 43 (73%) cases of G1-PCC a bipolar meiotic spindle was found instead of sperm astral microtubules. From this we conclude that unactivated oocytes contain active factors causing chromatin condensation as well as factors responsible for duplication of sperm centrosome. Failure of oocyte actovation was the most frequent cause of fertilization failure. As many as 125 (69%) of unfertilized oocytes remained in MII. In one fourth of these we noted damages of the second meiotic spindle. More rarely (in 11%) the arrest of the cell cycle was noted in anaphase II. Activation and gynogenetic oocyte development was discovered in 36 (20%) analyzed cases. Among more frequent fertilization defects in activated oocytes, asynchrony in male and female pronucleus development (in 18% of activated oocytes) was prevailing. In 601 ICSI cycles we found only one case of recurrent fertilization failure of all oocytes after ICSI due to the absence of sperm astral microtubules. SImultaneous observation of chromatin and microtubules in unfertilized oocytes is a method suitable for detecting the possible of oocyte fertilization failure.
Deskriptorji		OOCYTES MICROTUBULES CHROMOSOMES, HUMAN SPERMATOZOA SPERM-OVUM INTERACTIONS CHROMATIN OVULATION INDUCTION MICROSCOPY, FLUORESCENCE FERTILIZATION IN VITRO CELL DIVISION