30 research outputs found
Incidencia de malaria en una región endémica del estado Amazonas, Venezuela
This study was carried out to determine the incidence of malaria in an endemic region of Amazonas State, Venezuela. For this, 200 random samples were collected from symptomatic and asymptomatic individuals from San Fernando de Atabapo and Santa Barbara. Epidemiological factors were related to malaria infection, which was diagnosed by microscopy observation and amplification of the 18S rDNA sequence by PCR. Malaria prevalence in these populations was 28.5%, whilst P. vivax and P. falciparum prevalences were 12 and 17%, respectively. No infection by P. malariae was found. A mixed infection was found on an asymptomatic individual. Prevalence patterns differed between age groups depending on the Plasmodium species. We found that 34.8% of the P. vivax and 15.2% of the P. falciparum infections were asymptomatic. The use of nets was helpful to prevent P. vivax infection, but did not protect against P. falciparum infection. The results suggest the presence of more than one mosquito vector in the area, displaying a differential pattern of infection for each Plasmodium species. There appear to be risk factors associated with malaria infections in some individuals. The population based approach and PCR diagnosis improved the accuracy of the statistical analysis in the study.Este estudio fue llevado a cabo para determinar la incidencia de malaria en una región endémica del estado Amazonas, Venezuela. Doscientas muestras tomadas al azar fueron colectadas de individuos sintomáticos y asintomáticos de San Fernando de Atabapo y Santa Bárbara. Factores epidemiológicos fueron relacionados con la infección de malaria, diagnosticada por observación microscópica y por la amplificación por PCR de la secuencia del ADNr 18S. La prevalencia de malaria en estas poblaciones fue 28.5%, en tanto que las prevalencias para P. vivax y P. falciparum fueron 12 y 17%, respectivamente. No se encontró infección por P. malariae. Se encontró una infección mixta en un individuo asintomático. Los patrones de prevalencia difirieron entre los grupos de edades, dependiendo de la especie de Plasmodium. Se encontró una frecuencia de infecciones asintomáticas de 34.8% y 15.2% para P. vivax y P. falciparum, respectivamente. El uso de mosquiteros fue útil para prevenir infecciones por P. vivax, pero no protegió de infecciones por P. falciparum. Los resultados sugieren la presencia de mas de un mosquito vector en el área, mostrando patrones diferenciales de infección para cada especie de Plasmodium. Pareciera existir factores de riesgo asociados con la infección de malaria en algunos individuos. El estudio a nivel poblacional y el diagnóstico por PCR mejoró la exactitud del análisis estadístico en este estudio
AMINOGLYCOSIDE RESISTANCE GENES IN Pseudomonas aeruginosa ISOLATES FROM CUMANA, VENEZUELA
The enzymatic modification of aminoglycosides by aminoglycoside-acetyltransferases (AAC), aminoglycoside-adenyltransferases (AAD), and aminoglycoside-phosphotransferases (APH), is the most common resistance mechanism in P. aeruginosa and these enzymes can be coded on mobile genetic elements that contribute to their dispersion. One hundred and thirty seven P. aeruginosa isolates from the University Hospital, Cumana, Venezuela (HUAPA) were evaluated. Antimicrobial susceptibility was determined by the disk diffusion method and theaac, aadB and aph genes were detected by PCR. Most of the P. aeruginosa isolates (33/137) were identified from the Intensive Care Unit (ICU), mainly from discharges (96/137). The frequency of resistant P. aeruginosaisolates was found to be higher for the aminoglycosides tobramycin and amikacin (30.7 and 29.9%, respectively). Phenotype VI, resistant to these antibiotics, was the most frequent (14/49), followed by phenotype I, resistant to all the aminoglycosides tested (12/49). The aac(6´)-Ib,aphA1 and aadB genes were the most frequently detected, and the simultaneous presence of several resistance genes in the same isolate was demonstrated. Aminoglycoside resistance in isolates ofP. aeruginosa at the HUAPA is partly due to the presence of the aac(6´)-Ib, aphA1 andaadB genes, but the high rates of antimicrobial resistance suggest the existence of several mechanisms acting together. This is the first report of aminoglycoside resistance genes in Venezuela and one of the few in Latin America
New Perspectives Related to the Bioluminescent System in Dinoflagellates: Pyrocystis lunula, a Case Study
Pyrocystis lunula is considered a model organism due to its bioluminescence capacity linked to circadian rhythms. The mechanisms underlying the bioluminescent phenomenon have been well characterized in dinoflagellates; however, there are still some aspects that remain an enigma. Such is the case of the presence and diversity of the luciferin-binding protein (LBP), as well as the synthesis process of luciferin. Here we carry out a review of the literature in relation to the molecular players responsible for bioluminescence in dinoflagellates, with particular interest in P. lunula. We also carried out a phylogenetic analysis of the conservation of protein sequence, structure and evolutionary pattern of these key players. The basic structure of the luciferase (LCF) is quite conserved among the sequences reported to date for dinoflagellate species, but not in the case of the LBP, which has proven to be more variable in terms of sequence and structure. In the case of luciferin, its synthesis has been shown to be complex process with more than one metabolic pathway involved. The glutathione S-transferase (GST) and the P630 or blue compound, seem to be involved in this process. In the same way, various hypotheses regarding the role of bioluminescence in dinoflagellates are exposed
Virulence factors and integrons are associated with MDR and XDR phenotypes in nosocomial strains of Pseudomonas aeruginosa in a Venezuelan university hospital
Multidrug resistance (MDR), virulence and transferable elements potentiate Pseudomonas aeruginosa’s role as an opportunistic pathogen creating a high risk for public health. In this study, we evaluated the possible association of multidrug resistance, virulence factors and integrons with intrahospital P. aeruginosa strains isolated from patients at Cumana hospital, Venezuela. Relevant clinical-epidemiological data were collected to study 176 strains (2009-2016) isolated from different hospital units. Bacterial resistance was classified as susceptible, low-level resistant (LDR), multidrug resistant (MDR) and extensively drugresistant (XDR). Most strains produced pyoverdine, DNase, gelatinase and hemolysin. Around 73% of the strains showed some type of movement. MDR and XDR strains increased from 2009 (24.2% and 4.8%, respectively) to 2016 (53.1% and 18.8%); while LDR decreased from 64.5% to 6.3%. The exoU and exoS genes were found in a significant number of strains (38.1 and 7.4%, respectively). Class I integrons were detected in 35.8% of the strains and the frequency was associated with resistance (42.9, 22.4, 41.4 and 61.9%, for susceptible, LDR, MDR and XDR, respectively). The MDR/XDR strains were positively associated with hemolysins and exoU, but negatively associated with bacterial twitching. MDR/XDR phenotypes were also associated with the Intensive Care Unit (ICU), septicemia, bronchial infection and diabetic foot ulcers, as well as long hospital stay (≥10 days) and previous antimicrobial treatment. High frequency of MDR/XDR strains and their association with classI integrons and virulence factors can increase the infection potential, as well as morbidity and mortality of patients attending this hospital and could spread infection to the community, creating a health risk for the region
Identificación de Escherichia coli enteropatógena en niños con síndrome diarreico agudo del Estado Sucre, Venezue
Introduction: Diarrheagenic Escherichia coli is an important causative agent of acute diarrheic syndrome. Objective: To identify clonal groups of enteropathogenic E. coli (EPEC), in 485 children with acute diarrhea aged 0 to 10 years attending health care centers in Arismendi, Benítez and Sucre municipalities, Sucre state, Venezuela, from March to December, 2011. Materials and methods: After obtaining the informed consent, stool samples were collected. Escherichia coli was identified using standard coproculture methods and serology with polyvalent and monovalent antisera. DNA was isolated, and eae (intimin) and bfpA (bundlin) genes were amplified through two multiplex polymerase chain reactions (PCR). Results: The presence of bacterial infection was determined in 39.6% of coprocultures. The prevalence of E. coli was 54.7%; 82.9% of these isolates were positive by serology for the evaluated serogroups and serotypes, which were mostly identified in children between 0 and 2 years (37.9%); 48.6% of E. coli strains amplified the eae gene; of these, 58.8% were classified as typical EPEC (eae+ y bfp+). EPEC II was the most common serogroup (38.7%), with predominance of typical EPEC (60%). In positive strains for eae gene, the β intimin allele was the most frequently identified (74.5%). Only four strains with O157:H7 serotype were identified, which showed no PCR amplification of the eae and bfpA genes. Conclusion: This study showed the importance of molecular tests to identify diarrheagenic E. coli strains causing clinical conditions of varying severity.Introducción. Escherichia coli es uno de los principales agentes causales del síndrome diarreico agudo.Objetivo. Identificar grupos clonales de E. coli enteropatógena en 485 casos de diarrea aguda en niños entre 0 y 10 años de edad atendidos en centros de salud de los municipios de Arismendi, Benítez y Sucre del estado Sucre, Venezuela, entre marzo y diciembre de 2011.Materiales y métodos. Previo consentimiento informado, se recolectaron muestras fecales y se identificó E. coli mediante coprocultivo estándar y serología con antisueros polivalentes y monovalentes. Se aisló el ADN y se amplificaron los genes eae (intimina) y bfpA (bundlina) mediante dos pruebas de reacción en cadena de la polimerasa (PCR) múltiples.Resultados. En 39,6 % de los coprocultivos se determinó la presencia de infección bacteriana. La prevalencia de E. coli fue de 54,7 %; 82,9 % de estas cepas fue positivo por serología para los serogrupos y el serotipo evaluados, principalmente en niños entre los 0 y los 2 años (37,9 %). El 48,6 % de las cepas de E. coli amplificaron para el gen eae y, de estas, 58,8 % se clasificó como cepas de E. coli enteropatógena típica (eae+ y bfp+). El ECEP II fue el serogrupo más frecuente (38,7 %), con predominio de bacterias E. coli enteropatógenas típicas (60 %). El alelo β de la intimina fue el más identificado (74,5 %) en las cepas positivas para el gen eae. Solo se identificaron cuatro cepas con el serotipo O157:H7 utilizando antisueros, las cuales no amplificaron mediante PCR para los genes eae y bfpA.Conclusiones. Este estudio demostró la importancia de aplicar pruebas moleculares en la identificación de las cepas de E. coli causantes de diarrea de diversa gravedad
Primer reporte de cepas de Enterobacter spp productoras de metalobetalactamasas de Venezuela
Clinical strains of Enterobacter were isolated from Cumana's Central Hospital in Venezuela, and classified as E. cloacae (21), E. aerogenes (7), E. intermedium (1), E. sakazakii (1) and three unclassified. The strains showed high levels of resistance, especially to SXT (58.1%), CRO (48.8%), CAZ (46.6%), PIP (46.4%), CIP (45.2%) and ATM (43.3%). This is the first report for South America of blaVIM-2 in two E. cloacae and one Enterobacter sp., which also showed multiple mechanisms of resistance. Both E. cloacae showed blaTEM-1, but only one showed blaCTX-M-15 gene, while no blaSHV was detected.Cepas clínicas de Enterobacter fueron aisladas del Hospital central de Cumaná en Venezuela, y se clasificaron como E. cloacae (21), E. aerogenes (7), E. intermedium (1), E. sakazakii (1) y 3 sin clasificar. Las cepas mostraron altos niveles de resistencia, especialmente a SXT (58.1%), CRO (48.8%), CAZ (46.6%), PIP (46.4%), CIP (45.2%) and ATM (43.3%). Este es el primer reporte de América del Sur de blaVIM-2 en dos cepas de E. cloacae y una de Enterobacter sp., las cuales también mostraron múltiples mecanismos de resistencia. Ambas especies de E. cloacae mostraron genes blaTEM-1, pero solo una mostro el gen blaCTX-M-15, mientras que blaSHV no fue detectado
Population Structure Shapes Copy Number Variation in Malaria Parasites.
If copy number variants (CNVs) are predominantly deleterious, we would expect them to be more efficiently purged from populations with a large effective population size (Ne) than from populations with a small Ne. Malaria parasites (Plasmodium falciparum) provide an excellent organism to examine this prediction, because this protozoan shows a broad spectrum of population structures within a single species, with large, stable, outbred populations in Africa, small unstable inbred populations in South America and with intermediate population characteristics in South East Asia. We characterized 122 single-clone parasites, without prior laboratory culture, from malaria-infected patients in seven countries in Africa, South East Asia and South America using a high-density single-nucleotide polymorphism/CNV microarray. We scored 134 high-confidence CNVs across the parasite exome, including 33 deletions and 102 amplifications, which ranged in size from <500 bp to 59 kb, as well as 10,107 flanking, biallelic single-nucleotide polymorphisms. Overall, CNVs were rare, small, and skewed toward low frequency variants, consistent with the deleterious model. Relative to African and South East Asian populations, CNVs were significantly more common in South America, showed significantly less skew in allele frequencies, and were significantly larger. On this background of low frequency CNV, we also identified several high-frequency CNVs under putative positive selection using an FST outlier analysis. These included known adaptive CNVs containing rh2b and pfmdr1, and several other CNVs (e.g., DNA helicase and three conserved proteins) that require further investigation. Our data are consistent with a significant impact of genetic structure on CNV burden in an important human pathogen
Detection of the infectious hypodermal and hematopoietic necrosis virus (IHHNV) in asymtomatic cultured white shrimp, litopenaeus vannamei (boone), in Venezuela
CONTENIDO
Editorial.
El Zauahre, Maziad
Fauna Silvestre / Wild Life
Detección del virus de la necrosis infecciosa hipodérmica y hematopoyética (IHHNV) en camarones blancos cultivados asintomáticos, Litopenaeus vannamei (boone), en Venezuela.
Detection of the infectious hypodermal and hematopoietic necrosis virus (IHHNV) in asymtomatic cultured white shrimp, litopenaeus vannamei (boone), in Venezuela.
Boada, Mélida; De Donato, Marcos y Rodulfo, Hectorina
Medicina Veterinaria/ Veterinary Medicine
Eficacia antihelmíntica de doramectina 1%, ivermectina 1% y ricobendazol 15% frente a nematodos gastrointestinales en ovinos de pelo.
Anthelmintic efficacy of doramectin 1%, ivermectin 1% and ricobendazol 15% against gastrointestinal nematodes in hair ovines.
Muñoz, Jesús A.; Angulo Cubillán, Francisco; Ramírez, Roger; Vale O., Oswaldo; Chacín, Evert; Simoes, David y Atencio, Arnoldo
Correlación entre PCR en exudado nasal y la reacción de tuberculina para la detección de organismos del complejo Mycobacterium tuberculosis en bovinos.
Correlation between PCR and tuberculin test for detection of Mycobacterium tuberculosis complex organisms in bovine cattle.
Morales Loredo, Alberto; Peñuelas Urquides, Katia; Álvarez Ojeda, Genoveva; Martínez Vázquez, Irma O.; Maldonado, Jesús; Mendoza Dávila, Gerardo y Milián Suazo, Feliciano
Expression and distribution of the complement receptor gC1qR in bovine sperm.
Expresión y distribución del receptor de complemento gC1qR en los espermatozoides bovinos.
Valeris, Robert; Villamediana, Patricia; Quintero, Armando; Parra, Omaira; Sandoval, Jorge and Ghebrehiwet, Berhane
Pathological anatomy study of a hemorrhagic disease in four (4) pigs.
Estudio anatomopatológico de una enfermedad hemorrágica en cuatro (4) cerdos.
Vale-Echeto, Oswaldo E.; Vásquez, Donitzi P.; Camacho Bracho, Jesús E.; Vale-Oviedo, Oswaldo R. and Oviedo de Vale, María G.
Parasitología / Parasitology
Studies on the life cycle of Haplorchis pumilio (Looss, 1896) (Trematoda: Heterophyidae) in Venezuela.
Estudios del ciclo de vida de Haplorchis pumilio (Loos, 1896) (Trematoda: Heterophyidae) en Venezuela.
Díaz, Marcos T.; Hernández, Luis Elena and Bashirullah, Abul K.
Producción Animal / Animal Production
Sustainable rural development: that distinguished stranger (a review).
El desarrollo rural sustentable: ese ilustre desconocido (una revisión).
Bustillo García, Lissette; Martínez Dávila, Juan Pablo and Gallardo López, Felipe
Efecto del extracto de Yucca schidigera en el perfil bioquímico y hemático de cerdos en crecimiento y engorde.Effects of yucca schidigera extract on biochemical and hematological profiles of growing and fattening pigs.
Espinosa Muñoz, Verónica; García Contreras, Adelfa del C.; Herrera Haro, José G.; Álvarez Macías, Adolfo G.; Estrada Barrón, Silvia G. y Meza Cortes, Miriam
Efecto de concentraciones crecientes de fósforo fítico sobre la actividad de las enzimas fitasa y fosfatasa alcalina en el Epitelio intestinal de ovinos jóvenes.
Effect of incresing concentrations of phytic phosphorus on the activity of the phytase and alkaline phosphatase enzymes in the intestinal epithelium of young sheep.
Pizzani, Pablo; Godoy, Susmira; León, Milagro; Rueda, Emma; Castañeda, María Virginia y Arias, Adelis
Efecto de la suplementación estratégica, régimen de implantes y condición sexual sobre la composición proximal y mineral de carne de bovinos cruda y cocida.
Effect of strategic supplementation, implant regime and gender on the proximate and mineral composition of raw and cooked bovine meat.
Arenas de Moreno, Lilia; Giuffrida-Mendoza, María; Bulmes, Lorelys; Uzcátegui-Bracho, Soján; Huerta-Leidenz, Nelson y Jerez’Timaure, Nancy
Tecnología de Alimentos / Food Science and Technology
Cuantificación de las concentraciones de metales pesados en tejidos de peces y crustáceos de la laguna de unare, estado Anzoátegui, Venezuela.Quantification of the concentrations of heavy metals in tissues of fish and crustaceans of the unare lagoon, Anzoátegui state, Venezuela.
Márquez, Aristide; Senior, William; Fermín, Ivis; Martínez, Gregorio; Castañeda, Julián y González, Ángel
Funcionalidad de una mezcla de gomas de Acacia glomerosa, Enterolobium cyclocarpum e Hymenaea courbaril en la preparación de helados de bajo contenido calórico.Functionality of a mixture of gums from Acacia glomerosa, Enterolobium cyclocarpum and Hymenea courbaril in the low fat ice-cream preparation.
Rincón, Fernando; León de Pinto, Gladys; Beltrán, Olga; Clamens, Carmen y Guerrero, Rocío
Efecto del consumo de cultivo de levaduras Saccharomyces cerevisiae y/o selenio en pollos de engorde expuestos a bajos niveles de aflatoxina B1 en la dieta. 2: morfología hepática.Effect of Saccharomyces cerevisiae culture and/or selenium intake on broiler exposed to low levels of aflatoxin B1 in the ration. 2: hepatic morphology.
Arrieta, Darwuin; Pérez, María L.; Hernández-Fonseca, Juan; Oviedo, María G.; Miranda, Silvio y Luengo, [email protected] analíticobimestra