[Ultrastructure of frozen and thawed ram sperm]. / Ultrastruktúra zmrazených a rozmrazených spermií barana.

With the aid of a transmission electron microscope we studied the ultrastructure of frozen and thawed ram sperm. The cryoprotective agents do not completely prevent the occurrence of structural changes in spermatozoa. The sperm membrane system is affected. The greatest and most frequent damage is to the acrosome, the cell membrane and mitochondria are less injured. We observed regional differences in the damage to the cell membrane. It is most damaged above the acrosome, least in the postacrosomal area and in the principal piece of the tail. We found considerable variability in the changes among individual spermatozoa from the same ejaculate. The changes are not in the nature of mechanical damage as a result of the occurrence of ice microcrystals. We therefore think that the occurrence of structural changes is dependent on damage at molecular level and consists of a change in the physical-chemical properties of membranes.

[The Oradea study regarding the epidemiology factors in ischemic cardiopathy]. / Studiul Oradea privind depistarea si epidemiologia factorilor de risc în cardiopatia ischemia. I) Hipercolesterolemia.

Cholesterolemia in a population of 100482 inhabitants of the Bihor district, subjected to screening for the risk factors in ischemic cardiopathy were studied. Together with hyperlipidemias other risk factors were detected: arterial hypertension, obesity, diabetes mellitus, smoking, ischemic alterations of the electrocardiogram, the influence of the noxious agents present at the working place, of the blood groups and disturbances of the menstrual cycle. The mean cholesteremia is of 205 ± 43.7 mgr% (M = 207 ± 43.7 mgr%; F = 204 ± 43.5 mgr%). The prevalence of cholesterolemia, in comparison with the higher normal limits in each age group over 15 years of age, is in the entire studied series, of 13.5%. The population in whom cholesterolemia exceeds 250 mgr% represents 13.92%.

[Agglutination and acrosome reaction of ram spermatozoa incubated in the bovine folicular fluid]. / Aglutinácia a akrozómová reakcia spermií barana, inkubovaných v bovinnej folikulárnej tekutine.

Fresh-ejaculated sperm of ram was incubated at a temperature of 38 degrees C in the bovine follicular fluid and homologous blood serum (blood plasma). The spermatozoa were studied in native state under a microscope with phase contrast and as ultra-thin sections under a transmission electron microscope. In the follicular fluid and in the blood serum, strong agglutination of spermatozoa occurred, with its maximum after about two hours. Only the heads of spermatozoa agglutinated, the flagella being loose were arranged parallelly. Although the progressive motility of spermatozoa was not observed, the motility of flagella was not affected. The investigation under the electron microscope showed that the agglutination occurred only in acrosomes of intact spermatozoa. It was also found out that the follicular fluid induced the acrosome reaction of spermatozoa. The course of the acrosome reaction is similar to that in the other mammals: first of all plasma membrane becomes undulated, then it fuses with the outer acrosome membrane, giving origin to vesicles within the entire acrosome, except the equatorial segment. The acrosome reaction was found in about 5% spermatozoa, and therefore it may be assumed that secretions of the oviduct and uterus play their role to induce the acrosome reaction.

[Ram sperm survival during the use of various solvents after deep freezing in liquid nitrogen]. / Prezivatel'nost spermií barana pri pouzití rôznych druhov riedidiel po hlbokom zmrazení v tekutom dusíku.

Suitability of three diluents for a deep-freezing of ram ejaculates and sperm survival after de-freezing and in the course of a six-hour incubation were investigated. The longest survival was found with the use of diluent containing Tris, fructose, and citric acid: 49.2% after de-freezing and 20.7% after six hours. The influence of the de-freezing procedure on the motility of spermatozoa can also be taken into consideration. The best proved rapid de-freezing without any diluent. The stated results serve for orientation only as the suitability of the diluents will be confirmed by the fertility of inseminated ewes.

[Variability of the thickness of the endometrium in sheep under the intravaginal effect of chlorsuperlutin]. / Variabilita hrúbky endometria u oviec pri intravaginálnom pôsobení chlórsuperlutinu

Variability of the endometrium thickness and surface epithelium in sheep after the effect of 20 mg of chlorsuperlutin (vaginal swabs soaked in this preparation) was studied. The results obtained demonstrate that at the estrus synchronization by means of the above mentioned preparation similar changes of the endometrium can be observed as those at the estrus without controlled sexual activity. It was found out that the variability of the endometrium thickness, both in cows and heifers, depended on the follicle-stimulating hormone evoking mucosal edematization in view of the phase of the cycle when the ovulation-inhibiting factor came into play. The endometrium thickness of 1499.5 mu on an average was found in sheep with synchronized estrus, and the epithelium thickness was, on an average, 24.7 mu. We observed, according to the results of the experiment, that the endometrium thickness varied even in a given animal; the changes were the same on the endometrium of both horns of uterus independent of the ovary showing cyclical changes. The endometrium gets thinner towards to oviduct, its thickness not being uniform in individual parts of uterus. The results can be distorted due to some artificial factors, e.g. the way of sampling, fixating media, etc. Nevertheless, an assessment of the variability of the endometrium thickness belongs to objective methods to examine the functional activity of ovaries and to find out the state of uterine mucosa.

[Dynamics of changes in the uterine glands of ewes during chlorsuperlutine-synchronized estrus]. / Dynamika zmien uterinných zliaz pri synchronizacii estru u oviec chlorsuperlutionom

Dynamics of uterine glands was studied in ewes after oestrus synchronization. Full-value oestrus was obtained in the ewes under study after the introduction of polyurethane vaginal tampons impregnated with 20 mg Chlorsuperlutine Spofa. Endometrium biopsy was used to collect samples after laparotomy. The number of uterine glands showed a significant increase, especially after the application of PMSG; the percentual proportion of glandular tissue in endometrium tree increases. There is an insular-type extension of glands. After ovulation there appear broadly luminized glands with numerous extension reaching up to the cellular layer of endometrium.