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Torres O.A.,Institute Parasitologia y Biomedicina Lopez Neyra | Calzada J.E.,Instituto Conmemorativo Gorgas Of Estudios Of La Salud Icges | Beraun Y.,Institute Parasitologia y Biomedicina Lopez Neyra | Morillo C.A.,Fundacion Cardiovascular de Colombia | And 3 more authors.
Infection, Genetics and Evolution

Genetic susceptibility to Trypanosoma cruzi infection and the development of cardiomyopathy is complex, heterogeneous, and likely involves several genes. Previous studies have implicated cytokine and chemokine genes in susceptibility to Chagas disease. Here we investigated the association between the interferon-gamma gene (IFNG) +874T/A polymorphism and Chagas disease, focusing on susceptibility and severity. This study included 236 chagasic patients (asymptomatic, n=116; cardiomyopathic, n=120) and 282 healthy controls from a Colombian population where T. cruzi is highly endemic. Individuals were genotyped for functional single nucleotide polymorphism (SNP; rs2430561; A/T) of the IFNG gene by amplification refractory mutational system PCR (ARMS-PCR). Moreover, clinical manifestations of Chagas in patients were analyzed. We found a significant difference in the distribution of the IFNG +874 "A" allele between patients and healthy controls (P=0.003; OR = 1.46, 95% CI, 1.13-1.89). The frequency of the IFNG +874 genotype A/A, which is associated with reduced production of interferon-gamma, was increased in the patients relative to controls (38.1% vs. 26.6%). We compared the frequencies of IFNG alleles and genotypes between asymptomatic patients and those with chagasic cardiomyopathy and found no significant difference. Our data suggest that the IFNG +874T/A genetic polymorphism may be involved in susceptibility but not in the progression of Chagas disease in this Colombian population. © 2010 Elsevier B.V. Source

Futami K.,Nagasaki University | Valderrama A.,Instituto Conmemorativo Gorgas Of Estudios Of La Salud Icges | Baldi M.,National University of Costa Rica | Minakawa N.,Nagasaki University | And 3 more authors.
Journal of Economic Entomology

The Asian tiger mosquito, Aedes albopictus (Skuse) (Diptera: Culicidae), is a vector of several human pathogens. Ae. albopictus is also an invasive species that, over recent years, has expanded its range out of its native Asia. Ae. albopictus was suspected to be present in Central America since the 1990s, and its presence was confirmed by most Central American nations by 2010. Recently, this species has been regularly found, yet in low numbers, in limited areas of Panamá and Costa Rica (CR). Here, we report that short sequences (∼558 bp) of the mitochondrial cytochrome oxidase subunit 1 (COI) and NADH dehydrogenase subunit 5 genes of Ae. albopictus, had no haplotype diversity. Instead, there was a common haplotype for each gene in both CR and Panamá. In contrast, a long COI sequence (∼1,390 bp) revealed that haplotype diversity (±SD) was relatively high in CR (0.72 ± 0.04) when compared with Panamá (0.33 ± 0.13), below the global estimate for reported samples (0.89 ± 0.01). The long COI sequence allowed us to identify seven (five new) haplotypes in CR and two (one new) in Panamá. A haplotype network for the long COI gene sequence showed that samples from CR and Panamá belong to a single large group. The long COI gene sequences suggest that haplotypes in Panamá and CR, although similar to each other, had a significant geographic differentiation (Kst = 1.33; P < 0.001). Thus, most of our results suggest a recent range expansion in CR and Panamá. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. Source

Saldana A.,Instituto Conmemorativo Gorgas Of Estudios Of La Salud Icges | Saldana A.,University of Panama | Chaves L.F.,National University of Costa Rica | Chaves L.F.,Hokkaido University | And 4 more authors.
American Journal of Tropical Medicine and Hygiene

American cutaneous leishmaniasis (ACL) transmission patterns have been increasingly associated with domestic and peridomestic environments. Here, we present results from an epidemiological survey of 94 people from 24 households in Trinidad de Las Minas, western Panama. We studied the role of sand fly abundance, housing quality, peridomicile landscape matrix, and vegetation structure on shaping household clinical ACL rate patterns at Trinidad de Las Minas. We found that sand fly abundance was significantly associated with household clinical ACL rates, with a 6% rate increase for each additional Lutzomyia gomezi sand fly found inside a domicile. Copyright © 2013 by The American Society of Tropical Medicine and Hygiene. Source

Torres O.A.,Institute Parasitologia y Biomedicina Lopez Neyra | Calzada J.E.,Instituto Conmemorativo Gorgas Of Estudios Of La Salud Icges | Beraun Y.,Institute Parasitologia y Biomedicina Lopez Neyra | Morillo C.A.,Fundacion Cardiovascular de Colombia | And 3 more authors.
Tissue Antigens

The aim of this study was to investigate the role of the IL-6 -174G/C gene polymorphism in susceptibility/resistance to Trypanosoma cruzi infection in two independent cohorts from Colombia and Peru. We determined the IL-6 -174G/C genotypes in a sample of 399 seronegative individuals and 317 serologically positive patients from Colombia and Peru. All individuals are from regions where T. cruzi infection is endemic. No statistically significant differences in the frequency of IL-6 -174G/C gene polymorphism between chagasic patients and controls or between asymptomatic and individuals with cardiomyopathy were observed. Our results do not support an evidence for a major role contribution of this IL-6 gene polymorphism in the susceptibility to or clinical manifestations of Chagas disease in these studied cohorts. © 2010 John Wiley & Sons A/S. Source

Silva Galdino T.,Instituto Oswaldo Cruz IOC | Menna-Barreto R.F.S.,Instituto Oswaldo Cruz IOC | Britto C.,Instituto Oswaldo Cruz IOC | Samudio F.,Instituto Oswaldo Cruz IOC | And 3 more authors.
Analytical Biochemistry

We have developed a cell disruption method to produce a protein extract using Trypanosoma cruzi cells based on a straightforward hypoosmotic lysis protocol. The procedure consists of three steps: incubation of the cells in a hypoosmotic lysis buffer, sonication in a water bath, and centrifugation. The final protein extract was designated TcS12. The stages of cell disruption at different incubation times were monitored by differential interference contrast microscopy. After 30 min of incubation in lysis buffer at 4 C, the T. cruzi epimastigote forms changed from slender to round-shaped parasites. Nevertheless, cell disruption took place following sonication of the sample for 30 min. The efficiency of the methodology was also validated by flow cytometry, which resulted in 72% of propidium iodide (PI)-labeled cells. To estimate the protein extraction yield and the differential protein expression, the proteomics profile of four T. cruzi strains (CL-Brener, Dm28c, Y, and 4167) were analyzed by liquid chromatography tandem mass spectrometry (LCMS/MS) on a SYNAPT HDMS system using the label-free MSE approach. ProteinLynx Global Server (version 2.5) with ExpressionE analysis identified a total of 1153 proteins and revealed 428 differentially expressed proteins among the strains. Gene ontology analysis showed that not only cytosolic proteins but also nuclear and organellar ones were present in the extract. © 2013 Elsevier B.V. All rights reserved. Source

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