Comparison of semen characteristics and histological structure of the testis from transgenic and non-transgenic rabbits

[EN] The aim of this study was to compare semen characteristics including sperm quantity, quality, and abnormalities, as well as histological structure of the testis of three-year old transgenic (human clotting factor, hFVIII, gene) and nontransgenic rabbits. For the experiment, 10 transgenic rabbits of F2 and F3 generations and 10 randomly selected non-transgenic males of the same breed and age were used as controls. All males were housed in individual cages, under a the same environmental conditions: photoperiod (14L:10D), temperature (18-20°C), and humidity (65-70%). Semen samples, collected once a week for 20 wk from each control and transgenic male, were analyzed by computer assited semen analysis within a few minutes following natural ejaculation into an artificial vagina. Concentration of spermatozoa was higher in the transgenic than in the non-transgenic group (P<0.001; 316.6±148.8 and 126.7±64.4¿106/ mL, respectively). Significant differences (P<0.1) between transgenic and non-transgenic males were observed also in spermatozoa motility (63.08 vs. 32.60%). Significantly higher (P<0.05) relative volume (8.08±2.89%) and diameter of testicular lumen (36.89±23.11 ¿m) were found in the transgenic animals compared to control animals (16.69±4.70%, 53.89±25.42 ¿m). Our results show that spermatozoa parameters and histological structure of the testis can be used for the characterization of male reproductive traits of older transgenic rabbits.This work was supported by the grant No: 2003 SP51/028 09 00/028 09 03 coordinated by the Slovak Academy of Science and by the grant of Ministry of Agriculture Slovak Republic (RÚVV 07-012). All experiments were approved according to ethical permission No. SK P 28004. We are grateful to Dr. Shoubadeep Roychoudhury for the English correction.Lukac, N.; Massanyi, P.; Flesarova, S.; Danko, J.; Makarevich, A.; Chrenek, P. (2009). Comparison of semen characteristics and histological structure of the testis from transgenic and non-transgenic rabbits. World Rabbit Science. 17(4):221-226. https://doi.org/10.4995/wrs.2009.64722122617

The camp analogue, dbcAMP can stimulate rabbit reproductive functions: I. Effect on ovarian folliculogenesis, ovulation and embryo production

The aim of our study was to examine the influence of administration of N6,2’-dibutyryladenosine 3’5’-cyclic monophosphate (dbcAMP), a cAMP agonist, on ovarian folliculogenesis and atresia, as well as on reproductive efficiency in rabbits, whose ovarian cycle and ovulation was induced by gonadotropins. Ovarian cycle and ovulation of control rabbits were induced by 20 IU/kg PMSG followed by 35 IU/kg hCG administration. Experimental animals received PMSG and hCG together with dbcAMP (at 5, 25 or 50 μg/animal). After ovulation and insemination, the animals were sacrificed. Ovaries were weighted, histological sections of ovaries were prepared, and the presence of ovulated and not ovulated follicles and different stages of atresia was evaluated by light microscopy. The eggs were flushed from the oviducts after insemination and cultured up to blastocyst cell stage. Numbers of ovarian Corpora lutea, ovulated oocytes and oocyte-derived zygotes and embryos reaching hatched blastocyst stage were determined. Administration of dbcAMP (at doses 25 or 50 μg/animal, but not at 5 μg/animal) was able to increase the proportion of follicles with cystic and luteinization-related atresia. Furthermore, dbcAMP (50 μg/animal, but not lower doses) increased the ovarian mass, number of Corpora lutea, number of harvested oocytes, zygotes and embryos at blastocyst stage derived from these zygotes after culture. These data demonstrate that dbcAMP can stimulate rabbit ovarian follicle atresia, ovulation, oocyte, zygote and embryo yield and development. Furthermore, they confirm in the involvement of cyclic nucleotide-dependent intracellular mechanisms in the control of rabbit reproductive functions and potential practical usefulness of dbcAMP in improving animal reproduction and fertility

“Cell-Free Therapeutics” from Components Secreted by Mesenchymal Stromal Cells as a Novel Class of Biopharmaceuticals

Regenerative medicine is a fast growing multidisciplinary field aiming at the regeneration or replacement of damaged cells, tissues, or organs. Adult multipotent mesenchymal stromal cells (MSCs) are often used as a principal therapeutic tool in this field. Along with differentiation potency, MSCs secrete a wide spectrum of paracrine factors and extracellular vesicles participating in tissue repair and regeneration. Thus, for injuries that require trophic stimulation, cell survival support, and/or resident stem cells activation to be restored, one can apply MSC-conditioned medium, a combination of products and extracellular vesicles in cell culture growth medium, secreted by MSC. It could mediate most of beneficial regenerative effects of MSC without possible side effects of using MSC themselves. However, before the clinical application of this promising biopharmaceutical, several issues such as manufacturing protocols, quality control, and others must be addressed. Subsequently, we highlight the questions considering donor material variability, manufacturing, cell culture medium and auxiliary components selection, and potency tests development

Effect of Nickel Administration in vivo on the Testicular Structure in Male Mice

The aim of this study was to describe the effects of nickel (NiCl2) on murine testicular structure. Experimental animals were injected intraperitoneally with a single dose of 20 mg NiCl2 per kg of body mass (group A, n = 5) and 40 mg NiCl2 per kg b. m. (group B, n = 5). The group without injection (n = 5) was the control (C). Animals were killed 48 hours after administration of nickel. The body mass of animals, the mass of testes and the testes : body mass ratio were not significantly affected. In both experimental groups a significant (p p p < 0.05 - 0.001) after nickel administration. Evaluation of the lumen diameter in the seminiferous tubule showed a significant increase in both experimental groups. The data of the perimeter of seminiferous tubules corresponded with those of the seminiferous tubule diameter. TUNEL assay detected a higher frequency of localized apoptosis in the interstitium of nickel-administered animals compared to control group. Our findings clearly suggest a negative effect of nickel on the structure as well as on the function of the seminferous epithelium at the site of spermatozoa production

Observations of high-velocity SAPS-like flows with the King Salmon SuperDARN radar

In this study, a focused investigation of the potential for the King Salmon (KS) SuperDARN HF radar to monitor high-velocity flows near the equatorial edge of the auroral oval is undertaken. Events are presented with line-of-sight velocities as high as 2km/s, observed roughly along the L-shell. Statistically, the enhanced flows are shown to be typical for the dusk sector (16:00&amp;ndash;23:00&amp;nbsp;MLT), and the average velocity in this sector is larger (smaller) for winter (summer) conditions. It is also demonstrated that the high-velocity flows can be very dynamical with more localized enhancements existing for just several minutes. These short-lived enhancements occur when the luminosity at the equatorial edge of the auroral oval suddenly decreases during the substorm recovery phase. The short-lived velocity enhancements can be established because of proton and ion injections into the inner magnetosphere and low conductance of the ionosphere and not because of enhanced tail reconnection. This implies that some KS velocity enhancements have the same origin as subauroral polarization streams (SAPS)

First E region observations of mesoscale neutral wind interaction with auroral arcs

We report the first observations of E region neutral wind fields and their interaction with auroral arcs at mesoscale spatial resolution during geomagnetically quiet conditions at Mawson, Antarctica. This was achieved by using a scanning Doppler imager, which can observe thermospheric neutral line-of-sight winds and temperatures simultaneously over a wide field of view. In two cases, the background E region wind field was perpendicular to an auroral arc, which when it appeared caused the wind direction within ∼50 km of the arc to rotate parallel along the arc, reverting to the background flow direction when the arc disappeared. This was observed under both westward and eastward plasma convection. The wind rotations occurred within 7–16 min. In one case, as an auroral arc propagated from the horizon toward the local zenith, the background E region wind field became significantly weaker but remained unaffected where the arc had not passed through. We demonstrate through modeling that these effects cannot be explained by height changes in the emission layer. The most likely explanation seems to be the greatly enhanced ion drag associated with the increased plasma density and localized ionospheric electric field associated with auroral arcs. In all cases, the F region neutral wind appeared less affected by the auroral arc, although its presence is clear in the data

Формирование температурного поля грунтов у здания

Applying numerical methods an equation of heat transfer in the soil bonding with floors and building buried parts. Factors influencing on heat transfer have been investigated. New engineering technique for heat loss calculation through floor and buried wall parts has been elaborated. The obtained results have been used as a basis for preparation of a new building normative document.С использованием численных методов решено уравнение теплопроводности массива грунта, сопрягающегося с полами и заглубленными частями зданий. Проведено исследование влияния определяющих факторов на процессы теплопередачи. Предложена новая инженерная методика расчета потерь теплоты через полы по грунту и заглубленные части стен. Полученные данные использованы в качестве основы для разработки нового нормативного документа для строительства

СОПРОТИВЛЕНИЕ СДВИГУ ГРУНТА, АРМИРОВАННОГО ОБЪЕМНОЙ ГЕОРЕШЕТКОЙ

The method for determining ultimate resistance to shift of soils reinforced with a solid geolattice is developed. The condition of strength, being analogous to Mohr – Coulomb theory and with account of new coefficient values of an internal friction and bonding a «soil – geolattice» composite is worked out. The influence of a geolattice on the strength of a reinforced layer is estimated by the coefficient of reinforcement.Разработана методика определения предельного сопротивления сдвигу грунта, армированного объемной георешеткой. Получено условие прочности, аналогичное теории Мора – Кулона, с учетом новых значений коэффициента внутреннего трения и сцепления для композита «грунт – георешетка». Влияние георешетки на прочность армированного слоя оценивается коэффициентом армирования