Falconi C.E.,University las Fuerzas Armadas |
Yanez-Mendizabal V.,University of the Americas in Ecuador
Crop Protection | Year: 2016
The potential of dry heat treatment of Andean lupin seed to reduce seed–borne infection of the anthracnose pathogen, Colletotrichum acutatum, was investigated. First, the effect of dry heat (65 °C) over duration times of 0–96 h on germination and disease incidence after germination was evaluated for artificially– and naturally–infected seed. Dry heat treatment from 8 to 96 h reduced disease incidence after germination to undetectable levels in four cultivars compared with 7.5% disease incidence after germination in seed maintained at room temperature. Moreover, heat treatments of 4–12 h showed seed germination rates that were equivalent to the non–treated control. Under greenhouse conditions, dry heat treatments for 8 or 12 h reduced transmission of the pathogen from seed by 75 or 85%, respectively and dry heat treatment increased emergence of seedlings in comparison the non-treated control. Dry heat treatment is an environmentally friendly alternative for reducing anthracnose infections in Andean lupin seed. © 2016 Elsevier Ltd
Rodriguez-Pinto D.,Centro Internacional Of Entrenamiento E Investigaciones Medicas Cideim |
Rodriguez-Pinto D.,University of the Americas in Ecuador |
Saravia N.G.,Centro Internacional Of Entrenamiento E Investigaciones Medicas Cideim |
McMahon-Pratt D.,Yale University
BMC Infectious Diseases | Year: 2014
Background: An effective adaptive immune response requires activation of specific CD4 T cells. The capacity of B cells to activate CD4 T cells in human cutaneous leishmaniasis caused by Leishmania (Viannia) has not been evaluated.Methods: CD4 T cell activation by B cells of cutaneous leishmaniasis patients was evaluated by culture of PBMCs or purified B cells and CD4 T cells with Leishmania panamensis antigens. CD4 T cell and B cell activation markers were evaluated by flow cytometry and 13 cytokines were measured in supernatants with a bead-based capture assay. The effect of Leishmania antigens on BCR-mediated endocytosis of ovalbumin was evaluated in the Ramos human B cell line by targeting the antigen with anti-IgM-biotin and anti-biotin-ovalbumin-FITC.Results: Culture of PBMCs from cutaneous leishmaniasis patients with Leishmania antigens resulted in upregulation of the activation markers CD25 and CD69 as well as increased frequency of CD25hiCD127- cells among CD4 T cells. Concomitantly, B cells upregulated the costimulatory molecule CD86. These changes were not observed in PBMCs from healthy subjects, indicating participation of Leishmania-specific lymphocytes expanded in vivo. Purified B cells from these patients, when interacting with purified CD4 T cells and Leishmania antigens, were capable of inducing significant increases in CD25 and CD69 expression and CD25hiCD127- frequency in CD4 T cells. These changes were associated with upregulation of CD86 in B cells. Comparison of changes in CD4 T cell activation parameters between PBMC and B cell/CD4 T cell cultures showed no statistically significant differences; further, significant secretion of IFN-γ, TNF-α, IL-6 and IL-13 was induced in both types of cultures. Additionally, culture with Leishmania antigens enhanced BCR-mediated endocytosis of ovalbumin in Ramos human B cells.Conclusions: The capacity of B cells specific for Leishmania antigens in peripheral blood of cutaneous leishmaniasis patients to activate CD4 T cells and induce cytokine secretion is similar to that of all cell populations present in PBMCs. This capacity implicates B cells as a plausible target for modulation of the immune response to Leishmania infection as a therapeutic strategy. © 2014 Rodriguez-Pinto et al.; licensee BioMed Central Ltd.
Borchsenius F.,University of Aarhus |
Lozada T.,University of the Americas in Ecuador |
Knudsen J.T.,Lund University
Botanical Journal of the Linnean Society | Year: 2016
The evolution of a mechanism for attaining reproductive isolation between two diverging populations is a key step in the speciation process. We studied phenotypic variation, genetic differentiation, spatial distribution and reproductive ecology in two sympatric forms of the understorey palm Geonoma macrostachys in lowland tropical rainforest in Amazonian Ecuador. The two forms were morphologically and genetically distinct and differed in habitat preference, with one form being confined to moist flood plain habitats and the other occurring in terra firme and flood plain. Pollen transfer between the two forms was limited, but not totally prevented, by differences in flowering time, with flowers of the small form opening 2-3 h earlier than those of the large form. Differences in floral scent probably reduce the number of shared pollinators. A crossing experiment showed that pistillate flowers of either form produced fruit with pollen from the other form. We conclude that flowering biology may be a key factor in causing reproductive isolation between these closely related sympatric taxa. © 2016 The Linnean Society of London.
Pollination in the oil palms Elaeis guineensis, E. Oleifera and their hybrids (OxG), in tropical America [Polinização em palma azeiteira Elaeis guineensis, E. Oleifera e seus híbridos (OxG), na América tropical]
Melendez M.R.,University of the Americas in Ecuador |
Ponce W.P.,University of the Americas in Ecuador
Pesquisa Agropecuaria Tropical | Year: 2016
Oil palm (Elaeis guineensis) is very important in the Central and South American economies. Plants suffer from a devastating fungal disease known as “lethal decay” or “pudrición del cogollo”, in Spanish. Producer countries in Africa, Asia and tropical America have developed breeding programs that seek the tolerance of this disease by plants. The hybrids Elaeis guineensis x Elaeis oleifera (OxG) are resistant, but show physiological problems that affect commercial productivity. Natural pollination in these hybrids is low and manual pollination has high labor costs. The Coleoptera order is the most numerous and diverse natural pollinator, and the Elaeidobius genus has high efficiency and specificity to oil palm species. Elaeidobius kameronicus, Elaeidobius subvittatus and Mystrops costaricensis are the insects most commonly associated with oil palm inflorescences. Dynamics in insect populations change according to palm species and weather conditions. It is necessary to understand the insect behavior and population dynamics in OxG hybrids. Thus, recent studies on oil palm pollination, insect diversity and distribution in Latin America are discussed in this study. © 2016, Universidade Federal De Goias (UFG). All Rights Reserved.
Gonzalez-Andrade F.,Metropolitan Hospital |
Lopez-Pulles R.,Health Science University |
Espin V.H.,Hospital Carlos Andrade Marin |
Paz-Y-Mio C.,University of the Americas in Ecuador
Journal of Neonatal-Perinatal Medicine | Year: 2010
Objective: To examine the relationship between high altitude and microtia in Ecuador. Methods: We evaluated the epidemiological issues of 1298 cases of microtia reported in Ecuador from 2001 to 2007. It used data arising from the Vital Statistics National Reports: Annual Survey of Admissions and Discharges in this 7 year period. The register is national and population based, run and funded by the government. Results: It reported a total of 1298 cases of microtia out of 34654 cases of congenital malformations described in the registries. The overall prevalence was 2.38/10000 admissions/discharges calculated out of 5462263 admissions. An overall percentage (of 90.22%) were admitted before 19 years of age with the most prevalent group between 5 to 9 years of age (31.90%). There was progressive increase of cases every year; from 132 cases in 2001 to 304 in 2007. Total male cases in this study were 723 (55.70%) and female cases were 575 (44.30%). Tungurahua reported the highest prevalence of 18.31/10000 births, followed by Chimborazo, Azuay, Pichincha and Cotopaxi; all of them located over 2500 meters above sea level. It found that highest prevalence was 10.21 over 2700 meters above sea level followed by 8.28 over 2800 meters above sea level; with both having a cumulative prevalence of 8.81. Conclusion: There is a higher prevalence of microtia in patients living above 2500 meters above sea level. This study was not able to establish a clear relationship between microtia and different ethnic groups. © 2010 IOS Press and the authors.
Lopez-Cortes A.,University of the Americas in Ecuador |
Jaramillo-Koupermann G.,University of the Americas in Ecuador |
Munoz M.J.,University of the Americas in Ecuador |
Cabrera A.,University of the Americas in Ecuador |
And 4 more authors.
American Journal of the Medical Sciences | Year: 2013
INTRODUCTION:: The methylenetetrahydrofolate reductase (MTHFR), methionine synthase (MTR) and MTR reductase (MTRR) enzymes act in the folate metabolism, which is essential in methylation and synthesis of nucleic acids. The single nucleotide polymorphisms, MTHFR C677T, A1298C, MTR A2756G and MTRR A66G, cause alteration in the homocysteine levels and reduced enzymatic activity that generates deficiency in the assimilation of folates associated with DNA damage; that is, why it is important to know if the single nucleotide polymorphisms are associated with the pathological characteristics and development of prostate cancer, through a case-control retrospective study. METHODS:: DNA was extracted from 110 healthy and 104 affected men. The genotypes were determined by means of the polymerase chain reaction-restriction fragment length polymorphism and confirmed with genomic sequencing. RESULTS:: We found significant association between the genotypes of the MTHFR C677T polymorphism: C/T (odds ratio [OR] = 2.2; 95% confidence interval [CI] = 1.3-3.9; P = 0.008) and C/T + T/T (OR = 2.2; 95% CI = 1.3-3.9; P = 0.009) with the risk of prostate cancer development, and a slight association with MTRR A66G. Regarding pathological characteristics, we found significant risk between the C/T + T/T genotypes and the Gleason score (7-10) of poorly differentiated carcinoma (OR = 5.2; 95% CI = 1.7-16.2; P = 0.007). On the other hand, a significant association between A1298C, A66G, and A2756G with the pathological characteristics was not found (P > 0.05). CONCLUSIONS:: The MTHFR C677T polymorphism has significant effects on susceptibility to prostate cancer in Ecuadorian population, especially with the Gleason grade. © 2013 Lippincott Williams & Wilkins.
Francisco C.,University of the Americas in Ecuador |
Edwin T.,University of the Americas in Ecuador
Work | Year: 2012
The premise for this project is to implement an ergonomics program for the welding department of a car assembly company, considering that this area represents the highest occupational risk in relation to musculoskeletal injuries. The project also allows the demonstration of the different implementation processes of an ergonomics program; it also permits the determination of individual risks faced by workers of the welding department, and finally gives a chance of improving common injuries using the sentinel system. The main challenge is to reduce musculoskeletal injuries and absenteeism among welders through actions implemented by the ergonomics program. © 2012 - IOS Press and the authors. All rights reserved.
Alarcon F.,Hospital Eugenio Espejo |
Maldonado J.C.,University of the Americas in Ecuador |
Rivera J.W.,Hospital Eugenio Espejo
Neurologia | Year: 2011
Introduction: movement disorders have been associated with deep brain lesions. This study was performed to describe the frequency and characteristics of movement disorders in patients with intracranial tuberculomas. Methods: patients admitted consecutively between 1989 and 2004 to the Neurology Service of Eugenio Espejo Hospital (Quito, Ecuador), with a diagnosis of intracranial tuberculomas. All patients were examined clinically, and laboratory tests and imaging studies performed. Follow-up continued up to one year after the tuberculosis treatment was completed. A nested case-control analysis was performed to compare clinical characteristics, number and location of tuberculomas, between cases with movement disorders and controls. Results: forty-nine patients with tuberculomas (31.7 ± 20.5 years; males 53.1%) were studied. We found 16 cases (32.6%; 95%CI=19.9% - 47.5%) of movement disorders: chorea (n=7; 43.8%), tremor (n=5; 31.3%), dystonia (n=3; 18.8%) and myoclonus (n=1; 6.3%). Most cases (87.6%) developed early (10.4 ± 5.2 days of hospitalization). On admission, patients with movement disorders showed higher severity of the illness than controls (68.7 vs. 30.3%; p=.01), along with greater motor impairment (75.0 vs. 39.4%; p=.01) and sensitivity impairment (43.8 vs. 9.1%; p=.01). The cases showed higher frequency of multiple tuberculomas (68.7 vs. 36.4%), with deep brain deep (31.3 vs. 21.2%) and more severe motor impairment (25.0 vs. 12.1%). Conclusions: our results suggest a causal relationship between tuberculomas and movement disorders. Deep location and multiple tuberculomas may increase the risk of develop movement disorders. © 2010 Sociedad Española de Neurología.
Coral-Almeida M.,Institute of Tropical Medicine |
Coral-Almeida M.,Ghent University |
Coral-Almeida M.,International University of Ecuador |
Coral-Almeida M.,University of the Americas in Ecuador |
And 7 more authors.
PLoS Neglected Tropical Diseases | Year: 2015
Background Taenia solium cysticercosis is a zoonotic neglected disease responsible for severe health disorders such as seizures and death. Understanding the epidemiology of human cysticercosis (HCC) in endemic regions will help to expose critical information about the transmission of the disease, which could be used to design efficient control programs. This review gathered serological data on apparent prevalence of T. solium circulating antigens and/or seroprevalence of T. solium antibodies, apparent prevalence of human taeniasis and risk factors for HCC from endemic communities in order to understand the differences in exposure to the parasite and active infections with T. solium metacestodes in endemic areas around the world. Methods Three databases were used to search sero-epidemiological data from community-based studies conducted between 1989 and 2014 in cysticercosis endemic communities worldwide. The search focused on data obtained from T. solium circulating antigen detection by monoclonal antibody-based sandwich ELISA and/or T. solium antibody seroprevalence determined by Enzyme-linked Immunoelectrotransfer Blot (EITB). A meta-analysis was performed per continent. Principal Findings A total of 39,271 participants from 19 countries, described in 37 articles were studied. The estimates for the prevalence of circulating T. solium antigens for Africa, Latin America and Asia were: 7.30%(95% CI [4.23–12.31]), 4.08% (95% CI [2.77–5.95]) and 3.98% (95% CI [2.81–5.61]), respectively. Seroprevalence estimates of T. solium antibodies were 17.37% (95% CI [3.33–56.20]), 13.03% (95% CI [9.95–16.88]) and 15.68% (95% CI [10.25–23.24]) respectively. Taeniasis reported prevalences ranged from 0 (95% CI [0.00–1.62]) to 17.25% (95% CI [14.55–20.23]). Significance A significant variation in the sero-epidemiological data was observed within each continent, with African countries reporting the highest apparent prevalences of active infections. Intrinsic factors in the human host such as age and immunity were main determinants for the occurrence of infections, while exposure was mostly related to environmental factors which varied from community to community. © 2015 Coral-Almeida et al.
Paz-y-Mino C.,University of the Americas in Ecuador |
Beaty D.,University of the Americas in Ecuador |
Lopez-Cortes A.,University of the Americas in Ecuador |
Proano I.,Direccion Nacional de Articulacion de la Red Publica
International Journal of Pediatric Otorhinolaryngology | Year: 2014
Objective: The frequency of GJB2 mutations and of the del(GJB6-D13S1830) mutation has not been established among the Ecuadorian mestizo population diagnosed with autosomal recessive non-syndromic hearing loss. A genetic analysis was therefore designed in order to do so. Methods: The sample population included 111 subjects of which 26 were autosomal recessive non-syndromic hearing loss probands. Posterior to PCR amplification, sequencing analysis of exon 2 was used for mutational detection of the GJB2 gene; a multiplex PCR method was used for detection of the del(GJB6-D13S1830) mutation. The ratio of subjects with a certain state of the mutation (heterozygous/homozygous) is expressed as a percentage and significant differences between probands and controls were calculated using Fisher's exact test; P < 0.05 was considered significant. Results: A total of 104 mutations belonging to 8 allelic variations were identified. The most common being the V27I (58.9%); however, as this variation is a non-pathogenic polymorphism, Q7X, with a total of 19 mutated alleles, was the most frequent mutation (18.3%). The V27I polymorphism was the only variation distributed homogenously among probands and controls (P= 0.351). Based on physical analyses of multiple patients we confirm that Q7X causes a non-syndromic form of hearing loss and propose that it is a possible predominant mutation in the Ecuadorian population. Conclusions: This is the first study of its kind among the Ecuadorian population and a preliminary step in establishing GJB2 and del(GJB6-D13S1830) mutational frequencies in this population; it is also the first to report of such a high frequency of the Q7X mutation. The data presented here brings Ecuador a step closer to providing more efficient treatment for a broader number of patients; additionally, it contributes to a better understanding of the relationship between autosomal recessive non-syndromic hearing loss and mutations on the GJB2 gene. © 2014 Elsevier Ireland Ltd.