A study of a population of Nyssomyia trapidoi (Diptera: Psychodidae) caught on the Pacific coast of Ecuador

Background

Cutaneous leishmaniasis is endemic to the Pacific coast of Ecuador, and Nyssomyia trapidoi is considered to be its main vector. Dujardin et al. [1] recorded some differences in body pigmentation and isoenzymatic profiles in sympatric populations of Ny. trapidoi from the Pacific coast of Ecuador and suggested the existence of two cryptic species.

Methods

Entomological collections were performed in November 2008 and March 2011 in the locality of Paraíso Escondido using CDC miniature light traps and human bait. Morphological, isoenzymatical and molecular (sequencing of cytochome b and cytochrome c oxidase 1 of the mitochondrial DNA) analyses, such as detection of Leishmania DNA and phlebovirus RNA in some females, were performed.

Results

Neighbor-joining trees from mitochondrial sequences grouped all of Ecuadorian Ny. trapidoi (including the two color variants) in one cluster, except for two specimens which clustered separately in both genes. Isoenzymatic characterization confirmed that the color variants belong to the same population. Additionally, 11.5% of females were found by PCR to contain Endotrypanum monterogeii kinetoplastid DNA. All pools of Ny. trapidoi were negative for phlebovirus RNA.

Conclusion

Analysis of mitochondrial gene sequences and isoenzymes was unable to support the existence of two sibling species within Ny. trapidoi, which is a probable vector of Endotrypanum monterogeii.

[Phenotypic characterisation of 35 Colombian children with an imaging diagnosis of schizencephaly]

INTRODUCTION

Schizencephaly is the most frequent neuronal migration disorder. It is classified according to the type of lip (closed or open). Clinical features vary from the asymptomatic patient to severe neurological compromise.

AIM

To describe the clinical characteristics of children who have been diagnosed with schizencephaly and their correlation with radiological findings.

PATIENTS AND METHODS

Thirty-five Colombian children (17 males and 18 females) with a neuroimaging diagnosis at a mean age of 20.2 months were characterised phenotypically.

RESULTS

A history of perinatal events such as neonatal asphyxia (21.6%) and meconium-stained amniotic fluid (10.8%) were detected, together with maternal histories of failure to attend prenatal check-ups (34.3%), risk of preterm labour (10.8%) and smoking (10.8%). Familial histories of neurological diseases included epilepsy (14.3%) and mental retardation (5.7%). The open-lip type was predominant (60%) and was twice a common as the closed-lip type. Unilateral cases accounted for 62.9% of the total number, with a distribution between the two hemispheres in the same proportion, and 37.1% of cases were bilateral. The frontal lobe that was the most commonly involved. The most frequent manifestations were delayed psychomotor development (80%) and infantile cerebral palsy (80%). Epilepsy was present in 37.1% of cases and the predominant type of seizure was complex focal.

CONCLUSIONS

Tendencies similar to those reported in other series were observed, although with some differences, such as the higher mean age at the time of diagnosis and the lower incidence of resistant epilepsy. Limited access to prenatal check-ups, open-lip presentation, associated malformations and poor response to treatment seem to exacerbate the prognosis.

PCR and DNA Hybridization Methods for Specific Detection of Bean-Infecting Begomoviruses in the Americas and Caribbean

Begomoviruses are a major problem for common bean production in the tropics and subtropics of the Americas and the Caribbean. Multiplex polymerase chain reaction (PCR) primer pairs and nucleic acid hybridization probes have been developed to differentiate five bean-infecting begomoviruses and were used to assay reference and field-collected bean samples from Florida, Mexico, Central America, the Caribbean, and Brazil. Bean golden mosaic virus was found in Brazil, Bean calico mosaic virus in Mexico, and Bean golden yellow mosaic virus in Central America, the Caribbean, and Florida. Bean dwarf mosaic virus was not detected in any of the field samples. Tomato yellow leaf curl virus was found only in tomato samples from the Caribbean. These detection methods will provide tools to assist in the understanding of the epidemiology and diversity of geminiviruses as well as to facilitate resistance breeding, cultivar selection, and development of strategies for control.

Lactose maldigestion and milk intolerance: a study in rural and urban Mexico using physiological doses of milk

Lactose digestion capacity after ingestion of physiological doses of milk and its effect on milk intolerance and consumption were studied in rural and urban populations from three regions of Mexico with different milk intakes. All subjects (n = 926) received two treatments: whole milk (240 mL for children and 360 mL for adults) and the same amount of 90% lactose-hydrolyzed milk; 72% of the subjects also received as a third treatment a water solution containing lactulose (8 g for children and 10 g for adults). Lactose maldigestion determined by a hydrogen breath test was detected in 2 to 43% of subjects (depending on age group) and was higher in subjects from central and southern Mexico than in subjects from northern Mexico (P < 0.01). Only the experience of major symptoms of intolerance affected milk consumption, and these symptoms were present in 0 to 11% of children > 4 y old and in 7 to 17% of the 13- to 60-y-old subjects. No significant differences were found in lactose maldigestion or milk intolerance between rural and urban populations, but milk consumption was higher in urban areas (P < 0.01). Milk consumption in our study was affected primarily by factors not related to the capacity to digest or tolerate the lactose in milk.