Association of leptin receptor expression in placenta and peripheral blood mononuclear cell with maternal weight in birth outcomes.

INTRODUCTION: The pregnancy period represents the most intense period of growth and development. Pre-pregnancy weight influences weight gain during pregnancy. Leptin is a hormone mainly derived from white adipose tissue, during pregnancy leptin is also produced by the placenta. It has been suggested that the effects of placental leptin on the mother may contribute to endocrine-mediated alterations in energy balance; a dysregulation in leptin levels or its receptors may lead to poor birth outcomes. Therefore, the main goal of the present study was to analyze the differences in birth outcomes by maternal weight with the expression level of leptin receptor in maternal peripheral blood mononuclear cell (PBMC) and placental tissue. METHODS: Women with full-term gestation and its offspring were enrolled. Total RNA from maternal PBMC and placenta was obtained to perform the analysis of expression of the leptin receptor (LEPR) gene trough real-time PCR technique. Data were analyzed using one-way ANOVA or Mann-Whitney u test when applicable. Pearson correlation coefficient was used to determine the relationship between continuous variables (Stata v.13); p ≤ 0.05 was considered statistically significant. RESULTS: No statistically significant differences were found between LEPR expression level and the BMI studied groups in maternal PBMC and placental tissue. Interaction between gestational weight gain (GWG) and LEPR in maternal PBMC explain in a 32% the variability of the newborn weight. CONCLUSIONS: LEPR expression level in maternal PBMC correlates with newborn measurements independent from sex. GWG can affect fetal development by increasing fetal birth weight.

Pregnancy rates in hair sheep after Ovsynch synchronization and a combined intracervical fixed-time artificial insemination and 10-day mating period.

AIM: This study aimed to evaluate the pregnancy rates in hair ewes using an Ovsynch synchronization protocol under a breeding system that combines fixed-time insemination plus a 10-day mating period as an alternative. MATERIALS AND METHODS: Through an experimental study (n=27), ewes were randomly located into one of three treatments: (1) Pre-synch (n=9): Prostaglandin F2α (PGF2α)+Gonadotropin-releasing hormone (GnRH)+PGF2α+GnRH; (2) Ovsynch (n=9): GnRH+PGF2α+GnRH; and (3) control: Ewes bred by natural mating (NM) (n=9). Ewes were fixed-time inseminated (fixed-time artificial insemination [FTAI]) with fresh semen, collected just before the insemination time through vaginoscopy at 16 h after the second GnRH (gonadorelin) injection. Each experimental group was placed separately during 15 days and, after this time, fertile rams were allowed back with ewes for a 10-day mating period. Control group ewes remained with the rest of the herd suitable for breeding and were bred under NM. Pregnancy diagnosis was performed by ultrasound at 28-, 56-, and 84-day post-breeding to differentiate between FTAI and NM pregnancies. Total (FTAI±NM) pregnancy rates at 56-day post-breeding were used to compared Pre-synch, Ovsynch, and control. For this purpose, two-tailed proportions comparison z-test was used with a 95% confidence level, for testing as the null hypothesis whether two proportions were equal. RESULTS: Pregnancy rates were higher in control ewes (66.4%) than FTAI (46.6%). When pregnancy rates after a 10-day mating period (40%) were added, the final rate (86.6%) was significantly (p<0.05) higher in Ovsynch-based protocols. The pregnancy rate was significantly lower in FTAI ewes compared to FTAI +10-day mating group (p<0.05). The overall pregnancy rate was 88.0, 85.7, and 67.0 (p>0.05) for Pre-synch, Ovsynch, and control ewes, respectively. CONCLUSION: These results provide evidence on the benefits of combined FTAI protocols for improving the reproductive efficiency of sheep.

Histopathological changes in the liver and stomach of Didelphis virginiana (Didelphimorphia: Didelphidae) during natural infection with Gnathostoma turgidum (Nematoda: Gnathostomidae).

Gnathostoma turgidum is a nematode parasite that exploits the stomach of Virginian opossums, Didelphis virginiana, in Latin America. The opossum is the definitive host of G. turgidum in the wild. Intrahepatic growth and maturation of the parasite, subsequent migration to the stomach and spontaneous expulsion are common. However, the histopathological lesions caused by G. turgidum are poorly described. A better understanding of the life cycle of this parasite and the pathological changes in natural host-parasite interactions could help to clarify the progression of human infections caused by Gnathostoma binucleatum. The aim of this work was to study morphological changes in the liver and stomach of D. virginiana during natural infection and adult worm expulsion. Three opossums naturally infected with G. turgidum were captured from an endemic area of gnathostomosis. Three uninfected opossums captured from a non-endemic area were used as controls. The opossums were sacrificed at different stages of infection (March, May and December), and a histopathological study of their livers and stomachs was conducted. Injuries in livers were observed by histopathology - areas of necrosis and collagen septa were identified. Parasites caused nodules with necrosis on the periphery of lesions, and collagen fibres were also observed in stomachs. Collagen septa may be caused by antigenic remains of the parasite. Further immunological studies are necessary to verify that stimulation is caused by these factors.

Selected heavy metals and selenium in the blood of black sea turtle (Chelonia mydas agasiizzi) from Sonora, Mexico.

The concentration of heavy metals (Zn, Cd, Ni, Cu, Mn) and selenium (Se) was analyzed in blood collected from 12 black turtles (Chelonia mydas agasiizzi) captured in Canal del Infiernillo, Punta Chueca, Mexico. The most abundant metals were Zn (63.58 µg g(-1)) and Se (7.66 µg g(-1)), and Cd was the lower (0.99 µg g(-1)). The sequential concentrations of trace metals were Zn > Se > Cu > Mn > Ni > Cd. In conclusion, this information is important as a baseline when using blood as tissue analysis of heavy metals; however, these levels could represent recent exposure in foraging grounds of black turtles in the Sea of Cortez.

Non-typhi Salmonella serovars found in Mexican zoo animals.

The aim of the present study was to determine the bacteriological prevalence of subclinical non-typhi Salmonella infections in zoo animals and to determine the most frequently isolated serovars of the bacteria. A total of 267 samples were analyzed, including fecal samples from zoo animals and rodents, insects (Musca domestica and Periplaneta americana) and samples of the zoo animal's food. Salmonella was detected in 11.6% of the samples analyzed. Characterization of the isolates was performed with serotyping and pulsed-field gel electrophoresis. The following serovars were isolated: S. San Diego, S. Oranienburg, S. Weltevreden, S. Braenderup, S. Derby, S. 6,7, H:en x:- and S. 3,10, H:r:-. The isolates showed seven pulsed-field gel electrophoresis patterns with a Jaccard coefficient≥0.75 indicating a possible common origin. The prevalence of asymptomatic infections caused by Salmonella spp. in zoo animals was high. These findings demonstrate the diversity of Salmonella serovars in several captive wild animal species.

Trichomonas vaginalis: in vitro phagocytosis of lactobacilli, vaginal epithelial cells, leukocytes, and erythrocytes.

This paper explores the interaction of two strains of Trichomonas vaginalis, of high and low virulence, with the cell types present in the microenvironment of the parasite during human infections. With the use of transmission and scanning electron microscopy the sequence of internalization by T. vaginalis of Döderlein's lactobacilli, and of vaginal epithelial cells, leukocytes, and erythrocytes was documented. Furthermore, the degradation of ingested material by colocalization of acid phosphatase activity in phagocytic vacuoles was demonstrated. Phagocytosis of all cell types analyzed was found in both strains studied, although the highly virulent strain internalized target cells more rapidly than the less virulent one. Ultrastructural evidence indicated that phagocytosis takes place through two distinct mechanisms, only one involving the formation of a phagocytic stoma, characteristic of professional phagocytes. T. vaginalis phagocytosis may be both an efficient means of obtaining nutrients for the parasite and a significant factor in the pathogenesis of trichomonal infections of the human genitourinary tract.

Is the immune system necessary for placental reproduction? A hypothesis on the mechanisms of alloimmunotherapy in recurrent spontaneous abortion.

Recurrent spontaneous abortion is being treated with alloimmunotherapy which consists of the inoculation of allogeneic mononuclear cells. However the mechanisms explaining the benefits of this therapy are not clear yet. Taking the immunotrophic hypothesis as the paradigm of the field of reproductive immunology, hereby we present a hypothesis to propose a role for the immune system in reproduction and at the same time to explain how alloimmunotherapy may work. We base our view on several facts: first, immunodeficient mice reproduce--albeit their progeny may not be as robust and numerous as that from normal individuals. Second, maternal lymphocytes cross the placenta and may induce graft versus host disease. Third, graft versus host disease in newborn F1 mice inoculated with paternal lymphocytes can be prevented by inoculation of the mother with the same paternal lymphocytes before and during pregnancy. We propose that: 1) the immune system by itself is not necessary for placental reproduction; 2) the immune system plays its major role in reproduction by counteracting the allogeneic response generated against the fetus; 3) recurrent spontaneous abortion represents a type of graft versus host disease induced by maternal cells infiltrating the fetus; and 4) alloimmunotherapy induces an antiidiotypic response necessary to counteract the graft versus host reaction in the fetus.