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Axonal projection is controlled by discrete regions localized at the neuroepithelium, guiding the neurite growth during embryonic development. These regions exert their effect through the expression of a family of chemotropic molecules, which actively participate in the formation of neuronal connections of the central nervous system in vertebrates. Previous studies describe prosomere 1 (P1) as a possible organizer of axonal growth of the rostral rhombencephalon, contributing to the caudal projection of reticulospinal rhombencephalic neurons. This work studies the contribution of chemotropic signals from P1 or pretectal medial longitudinal fascicle (MLF) neurons upon the caudal projection of the interstitial nuclei of Cajal (INC). By using in ovo surgeries, retrograde axonal labeling, and immunohistochemical techniques, we were able to determine that the absence of P1 generates a failure in the INC caudal projection, while drastically diminishing the reticulospinal rhombencephalic neurons projections. The lack of INC projection significantly decreases the number of reticulospinal neurons projecting to the MLF. We found a 48.6% decrease in the projections to the MLF from the rostral and bulbar areas. Similarly, the observed decrease at prosomere 2 was 51.5%, with 61.8% and 32.4% for prosomeres 3 and 4, respectively; thus, constituting the most affected rostral regions. These results suggest the following possibilities: i, that the axons of the reticulospinal neurons employ the INC projection as a scaffold, fasciculating with this pioneer projection; and ii, that the P1 region, including pretectal MLF neurons, exerts a chemotropic effect upon the INC caudal projection. Nonetheless the identification of these chemotropic signals is still a pending task.

Immunological diagnostic methods for Trypanosoma cruzi depend specifically on the presence of antibodies and parasitological methods lack sensitivity during the chronic and “indeterminate” stages of the disease. This study performed a serological survey of 1,033 subjects from 52 rural communities in 12 of the 18 municipalities in the state of Queretaro, Mexico. We detected anti-T. cruzi antibodies using the following tests: indirect haemagglutination assay (IHA), indirect immunofluorescence assay (IFA), ELISA and recombinant ELISA (rELISA). We also performed Western blot (WB) analysis using iron superoxide dismutase (FeSOD), a detoxifying enzyme excreted by the parasite, as the antigen. Positive test results were distributed as follows: ELISA 8%, rELISA 6.2%, IFA and IHA 5.4% in both cases and FeSOD 8%. A comparative study of the five tests was undertaken. Sensitivity levels, specificity, positive and negative predictive values, concordance percentage and kappa index were considered. Living with animals, trips to other communities, gender, age, type of housing and symptomatology at the time of the survey were statistically analysed using SPSS software v.11.5. Detection of the FeSOD enzyme that was secreted by the parasite and used as an antigenic fraction in WBs showed a 100% correlation with traditional ELISA tests.

Plants that are traditionally used by the Mexican population, including Calendula officinalis Linn., Salvia officinalis and Hypericum perforatum, possess important nutraceutical properties and have been empirically tested as treatments for diverse diseases and inflammation. Infusions prepared with these plants at 1% (w/v) were tested for their phenolic compound content and in vitro antioxidant activity and administered to rats fed high fructose and saturated fat diets for 12 weeks. The total phenol and flavonoid content and DPPH and ABTS+ antioxidant activity were higher for the H. perforatum infusion group. Body weight gain was prevented by all of the infusion treatments, and a significant reduction in adipocyte volume and fat content was observed only after treatment with H. perforatum and S. officinalis; both infusions improved the glycaemic state and insulin resistance. Only the H. perforatum infusion enhanced adiponectin levels and decreased serum leptin and TNF-α levels. In conclusion, infusions prepared with certain plants could be useful to treat obesity, insulin resistance and systemic inflammation.

Diabetes is a disease characterized by a hyperglycemic stage that leads to a chronic inflammatory state. We evaluated the in vivo effect of a diet supplemented with 25 % cooked black bean cultivar Negro 8025 (N8025) flour in streptozotocin-induced diabetic rats. The effect was assessed before (preventive-treatment) and after (treatment) the onset of diabetes. There is a significant decrease of total phenolic, tannins and anthocyanins content after cooking, and the concentration of most of the single phenols analyzed are only slightly decreased. The treatment group showed a significant reduction of glucose (22.8 %), triglycerides (21.9 %), total cholesterol (29.9 %) and LDL (56.1 %) that correlates with a protection of pancreatic s-cells. The diet with N8025 flour before the induction of diabetes did not exert a protective effect (glucose levels are similar to the diabetic control) but they have low levels of total cholesterol (47.5 %) and LDL (56.1 %). The preventive-treatment group did not inhibit the increase of TNF-α and IL-1β, whereas the treatment group did, compared to the diabetic control. Therefore, N8025 bean supplementation can be recommended to control diabetes.

Increased retinal vasopermeability contributes to diabetic retinopathy, the leading cause of blindness in working-age adults. Despite clinical progress, effective therapy remains a major need. Vasoinhibins, a family of peptides derived from the protein hormone prolactin (and inclusive of the 16-kDa fragment of prolactin), antagonize the proangiogenic effects of VEGF, a primary mediator of retinal vasopermeability. Here, we demonstrate what we believe to be a novel function of vasoinhibins as inhibitors of the increased retinal vasopermeability associated with diabetic retinopathy. Vasoinhibins inhibited VEGF-induced vasopermeability in bovine aortic and rat retinal capillary endothelial cells in vitro. In vivo, vasoinhibins blocked retinal vasopermeability in diabetic rats and in response to intravitreous injection of VEGF or of vitreous from patients with diabetic retinopathy. Inhibition by vasoinhibins was similar to that achieved following immunodepletion of VEGF from human diabetic retinopathy vitreous or blockage of NO synthesis, suggesting that vasoinhibins inhibit VEGF-induced NOS activation. We further showed that vasoinhibins activate protein phosphatase 2A (PP2A), leading to eNOS dephosphorylation at Ser1179 and, thereby, eNOS inactivation. Moreover, intravitreous injection of okadaic acid, a PP2A inhibitor, blocked the vasoinhibin effect on endothelial cell permeability and retinal vasopermeability. These results suggest that vasoinhibins have the potential to be developed as new therapeutic agents to control the excessive retinal vasopermeability observed in diabetic retinopathy and other vasoproliferative retinopathies.