Rafael Bustos-Saldaña

Distribution and infection of triatomines (Hemiptera: Reduviidae) by Trypanosoma cruzi in the state of Michoacán, Mexico

An entomological study of triatomine species was carried out to assess their prevalence in 10 localities of the state of Michoacán, Mexico. Entomological indices were calculated to estimate the risk for vector-borne transmission of Trypanosoma cruzi to the human population in this area. Four triatomine species (Triatoma barberi, Triatoma dimidiata, Meccus pallidipennis and Meccus longipennis) were collected from the study area. This is the first report of M. longipennis and T. dimidiata in Michoacán. M. pallidipennis was significantly (p < 0.05) more abundant than any of the other species collected in the study area. Infection indices were greater than 50% for each of the four collected triatomine species. Significantly more triatomines were collected from intradomiciliary areas than from peridomiciliary or sylvatic areas. Infestation, crowding and density indices were low, whereas colonisation indices were high in five localities. The current vectorial conditions in the study area require continuous entomological and serological surveillance to diminish the risk of T. cruzi transmission to human populations.

Bionomics of Populations of Meccus pallidipennis (Stål), 1872 (Hemiptera: Reduviidae) from Mexico

1Área de Entomología Médica, Centro Universitario del Sur, Universidad de Guadalajara, Ciudad Guzmán, Jalisco, México, aibarra@cusur.udg.mx 2COFAA Grant Fellow, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, México, D. F., México 3Departamento de Salud y Bienestar, Centro Universitario del Sur, Universidad de Guadalajara, Ciudad Guzmán, Jalisco, México 4Departamento de Desarrollo Regional, Centro Universitario del Sur, Universidad de Guadalajara, Ciudad Guzmán, Jalisco, México

Life history of two abundant populations of Dipetalogaster maximus (Uhler, 1894) (Hemiptera: Reduviidae: Triatominae) in northwestern Mexico

ABSTRACT: We focused on the analysis of biological parameters of two different abundant populations of Dipetalogaster maximus (Uhler) (Hemiptera: Reduviidae: Triatominae) from northwestern Mexico. The biological parameters were related to hatching of eggs, life cycle, and meal needed for molting by each instar of two populations from environmentally similar areas (El Fandango and San Dionisio) with a similar number of available hosts as blood meal sources. The D. maximus populations from the two locations were evaluated and compared. No significant differences (P>0.05) were recorded for the average hatching time of the two cohorts. The median egg-to-adult development time and the number of blood meals at each nymphal group were significantly shorter (P<0.05) for the El Fandango cohort. The number of obtained females at the end of the cycles, number of eggs laid, and rate of egg hatching were significantly higher (P<0.05) for the El Fandango cohort. These results contribute to the estimation of abundances of the studied populations of D. maximus in areas where many tourists go for camping and have an increased risk of being bitten and infected by this species.

Polimorfismo rs4285184 del gen MGAT1 como factor de riesgo de obesidad en la población mexicana

BACKGROUND AND OBJECTIVE Obesity is a factor that contributes to the morbidity of certain diseases and to worldwide mortality. MGAT1 is a glycosyltransferase involved in the synthesis of protein-bound and lipid-bound oligosaccharides and its polymorphisms are possibly involved in the etiology of obesity. We investigated the association of the rs4285184 polymorphism of the MGAT1 gene with obesity in adults in the State of Colima, Mexico. METHODS A case-control study was conducted that included 244 subjects. All of them were grouped according to their percentage of body fat, determined through bioelectrical impedance, and they were genotyped for the rs4285184 polymorphism of the MGAT1 gene through PCR-RFLP. The results were analyzed for their association with the percentage of body fat. RESULTS The G allele had a frequency of 49.19 and 38.75% for the cases and controls, respectively (P=.020) (OR 1.53; 95% CI 1.068-2.193). The frequency of the A/G+G/G genotype was 75% in the obese patients, which was significantly higher compared with the 57.5% of the control group (P=.004) (OR 2.217; 95% CI 1.287-3.821). CONCLUSIONS The presence of the rs4285184 polymorphism of the MGAT1 gene increased the risk for developing body fat associated with obesity in the Mexican population.