Effect of heat treatment on oxalate and hydrocyanic acid levels of malanga corms of two cultivars (Xanthosoma sagittifolium and Colocasia esculenta) in a murine model.

Xanthosoma sagittifolium and Colocasia esculenta contain high levels of nutrients; but have naturally toxic compounds, oxalates and hydrocyanic acid (HCN). The objective of this work was to evaluate the effect of heat treatment on the concentration of antinutrients in malanga corms and its effect on mice. Malanga samples were heated to a boil for 0 to 120 min; oxalates and HCN were determined by spectrophotometry, at 710 and 510 nm, respectively. Pellets were prepared from raw malanga flour (15 and 50%), cooked malanga (15 and 50%) and wheat flour (control) and fed for nine weeks to five groups of six mice each. Cooking of X. sagittifolium corms for 80 min reduced oxalates present by 75% (143 to 35.6 mg/100 g sample), while oxalates in C. esculenta were reduced by 83% (345 to 57.8 mg/100 g sample). HCN levels became negligible after 20 min of cooking. During the nine weeks of feeding the different mice groups showed no significant difference (p > 0.05) between initial and final weight, with respect of the control; mice did not lose their appetite. The results indicate that the consumption of cooked malanga does not pose an evident risk to health, assessed by the reduced level of antinutrients, being an excellent alternative for feeding people in communities with prevalence of food insecurity.

What Do You Need to Know before Studying Chagas Disease? A Beginner's Guide.

Chagas disease is one of the most important tropical infections in the world and mainly affects poor people. The causative agent is the hemoflagellate protozoan Trypanosoma cruzi, which circulates among insect vectors and mammals throughout the Americas. A large body of research on Chagas disease has shown the complexity of this zoonosis, and controlling it remains a challenge for public health systems. Although knowledge of Chagas disease has advanced greatly, there are still many gaps, and it is necessary to continue generating basic and applied research to create more effective control strategies. The aim of this review is to provide up-to-date information on the components of Chagas disease and highlight current trends in research. We hope that this review will be a starting point for beginners and facilitate the search for more specific information.

Identification of Discrete Typing Units of Trypanosoma cruzi Isolated from Domestic Environments in Southeastern Mexico.

Background: The Trypanosoma cruzi parasite is the causal agent of Chagas disease, recognized by the World Health Organization as a neglected tropical disease. Currently there are seven discrete typing units (DTUs) of T. cruzi distributed in America, but there are still gaps about its distribution in some endemic regions. Materials and Methods: Seventeen units isolated from Chiapas and Oaxaca in Mexico were identified by amplification of the C-5 sterol desaturase gene. Results: Three DTUs of T. cruzi, TcI (6), TcII (10), and TcIV (1) were detected by comparing polymorphic sites in specific regions. Conclusions: New DTUs are reported for both states, where TcII was the most common DTU. The genetic characterization of the isolates can help to understand the epidemiology of Chagas disease.

Mini-exon gene reveals circulation of TcI Trypanosomacruzi (Chagas, 1909) (Kinetoplastida, Trypanosomatidae) in bats and small mammals in an ecological reserve in southeastern Mexico.

A wide variety of mammals are involved in the sylvatic cycle of Trypanosomacruzi, the causative agent of Chagas disease. In many areas in Latin America where T.cruzi is endemic, this cycle is poorly known, and its main reservoirs have not been identified. In this study we analyzed T.cruzi infection in bats and other small mammals from an Ecological Reserve in southeastern Mexico. From January through March 2021, we captured wild individuals to extract cardiac and peripheral blood, and infection was detected by PCR of the mini-exon gene. In bats, the prevalence of infection was 16.36%, while in small mammals the prevalence was 28.57%. All of the samples that were positive for T.cruzi were identified as the TCI genotype. Our findings suggest that this zone, situated at the periphery of urban zones might have epidemiological relevance in the sylvatic cycle of T.cruzi and needs to be monitored. The infection of bats in this area is particularly concerning since the flight pattern of this populations overlaps with human settlements. Despite being subject to conservation protections, there continue to be anthropogenic actions that disturb the study area, which could exacerbate risks to public health.

Trypanosoma cruzi: A review of biological and methodological factors in Mexican strains.

Trypanosoma cruzi, responsible for Chagas disease, is a serious public health problem in Latin America with eight million people infected in the world. Clinical manifestations observed in humans due to T. cruzi infection are largely associated with the wide biological and genetic heterogeneity of the parasite. This review presents an overview of the parasitological aspects of various strains of T. cruzi isolated mainly in Mexico, as well as an analysis of the methodological processes used to determine their virulence that could be influencing their biological characterization. We emphasize the importance of using uniform protocols to study T. cruzi virulence, taking into account factors related to: strain (i.e. developmental stage, lineage, biological origin, genetic variability), animal model used (i.e. role of hormones, host immune response, age) and methodology (i.e. inoculum size, inoculation route, and laboratory conditions used during strain maintenance). These uniform protocols will then allow proposing elements for understanding clinical evolution and management of the disease, for providing adequate treatment, and for developing tools for future vaccines against Chagas disease.