Oestrus synchronization treatment induces histomorphological changes on the uterine tube epithelium of the gilt.

The aim of this study was to determine the histomorphological changes that occurred in response to two treatments for oestrus synchronization in three different regions of the gilt's uterine tubes epithelium: the ampulla (AMP), ampulla-isthmic junction (AIJ) and isthmus (IST). Nine prepuberal gilts were divided into three groups (n = 3): (1) eCG 400 IU and hCG 200 IU (eCG/hCG), (2) progesterone agonist (P4) and (3) control group. The number of secretory cells (stained with periodic acid-Schiff reaction or PAS-positive cells) decreased in the AMP in the P4 treated group when compared to the control group, whereas, no difference was observed in the number of PAS-negative cells in the AMP of the three groups. A significant decrease in the number of PAS-positive cells was observed in the AIJ and IST of the P4 treated group when compared to the eCG/hCG and control groups. An increase in the number of PAS-negative cells was observed in the AIJ and IST in the P4 treated group. The epithelium height in the AMP and AIJ was increased in the eCG/hCG group when compared to the control and P4 groups. In this last group, we observed a reduced height compared with the other two groups for the AIJ. In the IST, there were no significant changes in the epithelium height of the control or the other two groups (eCG/hCG and P4). The epithelial cells of the P4 treated group had the least amount of cytoplasmic granules and the lowest intensity of PAS staining in the AMP, AIJ and IST. Animals treated with eCG/hCG showed an intermediate number of cytoplasmic granules and intensity in all regions evaluated. These data show that P4 treatment for synchronization induces a significant (P < 0.001) decrease of PAS-positive cells and staining intensity of cytoplasmic granules in the different regions studied and an increased number of PAS-negative cells in the AIJ and IST epithelium. Moreover, eCG/hCG treatment increased the height of the epithelium in the AMP and AIJ, while in this last region, the P4 treatment decreased the epithelium height. These results show that synchronization treatments with P4 and in a smaller proportion with eCG/hCG can modify the amount of PAS-positive and PAS-negative cells, and the epithelium height. This has influence in the secretory activity of the epithelium and possibly alters the fluid microenvironment of the gilt's uterine tube. The biological impact of regional variations in the epithelial cells of the gilt's uterine tube needs further investigation to understand the implications that the reproductive processes can have in the uterine tube.

A study of the process of apoptosis in animals infected with the contagious ecthyma virus.

Contagious ecthyma virus (CEV) is a disease caused by a parapoxvirus, also is a potent genetic carrier with the capacity for regulating apoptosis in the cells of infected skin, a mechanism that serves for evading the immune response of the host. It has been suggested that the virus may remain in the skin and be able to cause repeated infections in the same flock. The effect of infection as well as the presence of contagious ecthyma virus was evaluated in terms of lesions and apoptosis in the skin of animals, infected both naturally and experimentally. Samples used were obtained from a naturally infected sheep, 5 goats inoculated with CEV and a negative control. Samples obtained were longitudinally sectioned and processed using photon and electron microscopy, and embedded in paraffin and araldite. Samples embedded in paraffin were sectioned in 5 microm of thickness and dyed with orange eosin-hematoxilin G and Gomori's trichrom stain, apoptosis was demonstrated by the TUNEL assay, the viral antigen was revealed using polyclonal antibodies, and the presence of lymphocytes CD4+ and CD8+, with monoclonal antibodies. The samples processed in resin were cut to obtain semi-fine sections and dyed with toluidine blue-borax, and the ultra-fine sections were impregnated with lead citrate and uranyl acetate. Observations were similar in both, the natural infected animal and the experimental group. Infiltration was observed as well as images suggestive of a process of apoptosis. The TUNEL assay demonstrated that the number of epithelial cells undergoing apoptosis diminished during the process and increased among defense cells, until they almost disappeared at the beginning of healing. Cells undergoing apoptosis were located near the sebaceous glands and pilose follicles. The infiltrated lymphocytes gradually diminished. The viral antigen was observed in cells with morphology suggestive of apoptosis, located in sebaceous glands and pilose follicles. Using electron microscopy, cells with morphology compatible with that of lymphocytes were observed to be undergoing apoptosis, but there was little evidence of viral particles.

Rat embryo quality and production efficiency are dependent on gonadotrophin dose in superovulatory treatments.

The present study was performed to optimize a superovulation protocol in rats in order to produce a large number of good-quality embryos suitable to develop rat embryonic stem (rES) cells. We first evaluated the ovulation kinetics of three rat strains: Wistar, Fisher and ACI/N. Animals (n=30 per strain) were treated with 50 IU of pregnant mare serum gonadotrophin (PMSG), and ovulation was induced with 50 IU of human chorionic gonadotrophin (hCG) 50 h apart. Next, we evaluated the dose-response curves of PMSG and hCG in Wistar rats in order to obtain the highest number of embryos. The parameters evaluated for superovulation efficiency were: percentage of mated females, percentage of pregnant females and the average number of embryos collected per female. The results of these experiments suggested that the best dose combination was 50 IU for each hormone. Subsequent experiments, again with Wistar rats, were designed to test which of four hormonal combination treatments (30/30, 30/50, 50/30, and 50/50 IU of PMSG/hCG) will produce the largest numbers of good-quality embryos. Embryo quality was evaluated by embryo development uniformity, embryo morphology, embryo survival in an in vitro culture and embryo ability to generate rES-like cells. Results from these experiments showed that 30/50 IU of PMSG/hCG was the treatment that induced the best embryo quality. In conclusion, our results indicated that, in Wistar rats, the most appropriate hormonal combination dose for superovulation protocols with high number of good-quality embryos was 30 IU of PMSG and 50 IU of hCG given 50 h apart. We are performing further studies with rES-like cells produced with the present methodology to evaluate if they are able to participate in the production of germ-line chimeras.

CD16+ and CD16- human blood monocyte subsets differentiate in vitro to dendritic cells with different abilities to stimulate CD4+ T cells.

Experimental protocols for cancer immunotherapy include the utilization of autologous monocyte-derived dendritic cells (moDC) pulsed with tumor antigens. However, disease can alter the characteristics of monocyte precursors and some patients have increased numbers (up to 40%) of the minor CD16(+) monocyte subpopulation, which in healthy individuals represent 10% of blood monocytes. At the present, the capacity of CD16(+) monocytes to differentiate into DC has not been evaluated. Here, we investigated the ability of CD16(+) monocytes cultured with granulocyte- macrophage colony-stimulating factor, IL-4 and tumor necrosis factor-alpha to generate DC in vitro, and we compared them to DC derived from regular CD16(-) monocytes. Both monocyte subsets gave rise to cells with DC characteristics. They internalized soluble and particulate antigens similarly, and both were able to stimulate T cell proliferation in autologous and allogeneic cultures. Nevertheless, CD16(+) moDC expressed higher levels of CD86, CD11a and CD11c, and showed lower expression of CD1a and CD32 compared to CD16(-) moDC. Lipopolysaccharide-stimulated CD16(-) moDC expressed increased levels of IL-12 p40 mRNA and secreted greater amounts of IL-12 p70 than CD16(+) moDC, whereas levels of transforming growth factor-beta1 mRNA were higher on CD16(+) moDC. Moreover, CD4(+) T cells stimulated with CD16(+) moDC secreted increased amounts of IL-4 compared to those stimulated by CD16(-) moDC. These data demonstrate that both moDC are not equivalent, suggesting either that they reach different stages of maturation during the culture or that the starting monocytes belong to cell lineages with distinct differentiation capabilities.

[Identification of caprine arthritis encephalitis virus using histopathological, immunohistochemica, and ultrastructural examination of tissues from seropositive goats in Mexico]. / Identificación del virus de la artritis encefalitis caprina mediante el estudio histopatológico, inmunohistoquímico y ultraestructural, en tejidos de cabras seropositivas en México.

This study demonstrated the presence of viral particles suggestive of arthritis-encephalitis virus through the clinic, serologic, pathologic, immunohistochemic and ultrastructural studies in dairy goats. In the postmortem studies the tissues used were: synovial membrane, lungs and mammary gland from goats with clinical signs characteristic of the disease and positive for serum antibodies to the virus.