35 research outputs found
Información Investigador: Añez Reverol, Nestor Oswaldo
Doctorado1056IV - 2009; IV - 2003; II - 2000478 - 2009; 207 - 2005; 85 - 2003; 116 - 2001Bio-epidemiología de la enfermedad de Chagas y las Leishmaniasis.Diciembre de 2011Médico Veterinario+58 274 2401285Facultad de [email protected]
Supervivencia e infectividad de formas metacíclicas de Trypanosoma cruzi en alimentos experimentalmente contaminados
Publicado en el Boletín de Malariología y Salud Ambiental Vol. XLIX, Nº 1, Enero-Julio, 2009Se registra el tiempo de supervivencia de formas metacíclicas de Trypanosoma cruzi,
obtenidas del tracto digestivo de Rhodnius prolixus, sobre alimentos contaminados experimentalmente. Observaciones entre 1h y 18h post-contaminación revelaron la presencia de abundantes y activos
metacíclicos en los alimentos contaminados durante las primeras 6 horas, declinando la población de los mismos sobre la décima hora. La actividad de las formas metacíclicas no mostró diferencias
en alimentos contaminados en fase sólida o líquida. Asimismo, se demuestra la alta infectividad de metacíclicos de T. cruzi que sobreviven en alimento contaminado luego de ser ingeridos por un hospedador [email protected]
Supervivencia e infectividad de formas metacíclicas de Trypanosoma cruzi en alimentos experimentalmente contaminados
Se registra el tiempo de supervivencia de formas metacíclicas de Trypanosoma cruzi,
obtenidas del tracto digestivo de Rhodnius prolixus, sobre alimentos contaminados experimentalmente.
Observaciones entre 1h y 18h post-contaminación revelaron la presencia de abundantes y activos
metacíclicos en los alimentos contaminados durante las primeras 6 horas, declinando la población
de los mismos sobre la décima hora. La actividad de las formas metacíclicas no mostró diferencias
en alimentos contaminados en fase sólida o líquida. Asimismo, se demuestra la alta infectividad
de metacíclicos de T. cruzi que sobreviven en alimento contaminado luego de ser ingeridos por un
hospedador [email protected]@hotmail.co
Nuevos casos agudos de enfermedad de Chagas en el Occidente de Venezuela
Chagas en pacientes procedentes de regiones endémicas de
los estados Barinas (7) y Trujillo (2) al occidente de Venezuela,
2 de los cuales (22%) fueron fatales. Se dan detalles clínicos,
seroparasitológicos y moleculares en cada caso, y se discuten
aspectos ecoepidemiológicos. Se concluye sobre la
transmisión activa de Trypanosoma cruzi en estas regiones y
se clama por el establecimiento de una política de estado para
el control de la enfermedad de Chagas en [email protected]@hotmail.comNine new cases of acute Chagas disease in patients from
Barinas and Trujillo states in Western Venezuela are
presented. Two out of the 9 studied cases (22%) were fatal.
Clinical, sero-parasitologic, molecular and eco-epidemiologic
details are discussed. The present report allowed us to
conclude about the active Trypanosoma cruzi transmission in
Venezuela. Recommendation to establish control of Chagas
disease as a policy of state is given
Trypanosoma cruzi congenital transmission in wild bats
Trypanosoma cruzi congenital transmission in wild bats (Molossus molossus), associated with infected
Rhodnius prolixus in a natural habitat from a rural locality in western Venezuela, is reported. T. cruzi blood
circulating trypomastigotes in a pregnant batwere detected by parasitologicalmethods. Polymerase chain
reaction (PCR) assays carried out in samples from the heart and the fetus of the same infected female,
revealed the presence of T. cruzi-specific DNA in both of the tissues, demonstrating transmission of the
infection from the mother to the offspring. Eighty percent of the captured bats and 100% of the examined
fetuses frompregnant specimenswere shownto be infected by T. cruzi, indicating that M. molossus is a very
susceptible species for this parasite, and that T. cruzi congenital transmission is a common phenomenon in
nature. To our knowledge, this seems to be the first report on congenital T. cruzi transmission in wild bats
in Venezuela. The circulation of T. cruzi lineage I in the study areawas demonstrated by typing the isolates
from bats and triatomine bugs captured in the same habitat. The potential epidemiological implication of
these findings in areas where Chagas disease is endemic is discussed.78–[email protected]@[email protected]
Evaluation of conventional serological tests for the diagnosis of American cutaneous Leishmaniasis
Three serological tests (ELISA, IFAT, DAT) were evaluated using sera from selected
individuals with different American cutaneous leishmaniasis (ACL) clinical conditions. Reactivity in
at least 2 of the 3 named tests was established as a criterion for declaring a patient as sero-positive.
Prior to serological testing, people were diagnosed by clinical (presence of lesion = pl or scar=Sc),
parasitological (presence of parasites =pp), immunological (LST) and molecular (PCR) methods. For
a statistical comparison of the evaluated tests 4 groups of people were made up: 1) patients with
active leishmanial lesion (n=44; pl, pp, +LST, +PCR); 2) patients who had recovered from leishmanial
infection (n=43; Sc, +LST, +PCR); 3) asymptomatic individuals from endemic areas showing evidence
of having contacted Leishmania-parasites (n=40; +LST, +PCR) and 4) Leishmania-negative people
from the above localities where leishmaniasis is endemic and living under the same risk conditions,
considered as healthy controls (n=104; -LST, -PCR). Considering the above-established criteria
for sero-positives, the analysis of the results obtained with the 3 tests employed revealed very low
sensitivity values. Seropositive figures of 50% were recorded for the first group, 9% for the second
group, and 12.5% for the third group. Statistical analysis also revealed a low positive predictive value
(PPV=0.73), a low negative predictive value (NPV=0.49), and a low kappa coefficient value (k=0.114).
The present results raise questions about the use of the 3 conventional serological tests compared
here to detect ACL at any clinical [email protected]@[email protected]
Primoinfección por Trypanosoma cruzi previene re-infecciones severas en ratones
Publicado en el Boletín de Malariología y Salud Ambiental Vol. LI, Nº 2, Agosto-Diciembre, 2011Se evalúa el efecto de reinoculaciones por Trypanosoma cruzi en ratones experimentalmente infectados. De un total de 200 ratones que fueron infectados por vía intradérmica con un inóculo de 5x103 tripomastigotes metacíclicos provenientes de especimenes de Rhodnius prolixus, 52 sobrevivieron a la primo-infección luego de 23 semanas. De estos 45 fueron re-inoculados en la misma forma como en la infección primaria y siete fueron utilizados como controles infectados no re-inoculados. Observaciones sistemáticas llevadas a cabo en muestras de los ratones re-inoculados revelaron parasitemias significativamente menores que las detectadas durante la primo-infección. La evaluación serológica no mostró diferencias en los niveles de IgM e IgG entre ratones primo-infectados y los re-inoculados. Observaciones histopatológicas no mostraron cambios atribuibles al efecto de las re-inoculaciones en muestras de corazón y músculo esquelético. Una tasa similar de mortalidad fue observada en ratones primo-infectados, re-inoculados y controles infectados. Se concluye que re-inoculaciones con T. cruzi en ratones previamente infectados con el mismo parásito no producen reactivación de la infección similar al típico cuadro agudo. Asimismo, se sugiere que la primo-infección por T. cruzi previene una reinfección severa estableciendo un estado de protección y resistencia a subsecuentes infecciones. Se discuten las implicaciones epidemiológicas de los presentes [email protected] effect of Trypanosoma cruzi re-inoculations on experimentally infected mice was evaluated. Mice received a primary infection by intradermal inoculation of 5x103 T. cruzi metacyclic infective forms from laboratory infected Rhodnius prolixus. From 200 mice initially infected, 52 survived the course of the infection during 23 weeks. From these, 45 mice were re-inoculated and seven used as infected control. Two re-inoculations were performed using the same conditions as in the prime-infection. Observations on re-inoculated mice revealed a parasitemia level lower than that detected during the primary-infection. Serologic evaluation showed no variation in the immunoglobulin profile, maintaining similar IgM and IgG levels after re-inoculations. Similar mortality rates were observed in primary-infected, re-inoculated and infected control mice. No remarkable histopathological changes attributable to re-inoculation were detected. These results lead us to conclude that T. cruzi re-inoculation in mice previously infected with the same parasite does not produce a reactivation of infection similar to the typical acute clinical or immunological profiles. This also suggests that T. cruzi primary infection may prevent severe re-infection, establishing a protective stage making infected mice resistant to a second infection. Epidemiological implications of the present findings are discussed
Utilización de la Reacción en Cadena de la Polimerasa (PCR) para el diagnóstico de tripanosomiasis y anaplasmosis en muestras de sangre de animales domésticos
Taller teórico-práctico realizado del 26 al 29 de junio de [email protected]@[email protected]@ula.v
Análisis multivariante para discriminar especies de flebotominos (Diptera:Psychodidae). Lutzomyia cayennensis y Lutzomyia yencanensis
Editorial. Politica y Salud.Aniyar de Castro, LolitaLa inervación parasimpática cardíaca y su posible relación con el aneurisma apical ventricular izquierdo de los pacientes con Enfermedad de ChagasCardiac parasyimpathetic innervation and the apical left ventricular aneurysms of Chagas' heart disease.Dávila S., Diego F.Donis, José H.Torres M., ArgenisNavas, MaríaArata de Bellabarba, GabrielaVásquez, Carlos J.Figueroa, OrlandoNavarro, AlexisAmro, MarcialFaoddul; MerchedRossel R., OsmánGottberg, Carlos F.González G., José C.Correlación clínico-radiológica pulmonar en obreros de una fábrica de calPulmonary radiological clinical correlation in a lime factory workers.Calderón de Cabrera, LourdesCésaro de Castris, ElioSexualidad humana y causas de disfunciones sexualesHuman Sexuality and Sexual Dysfunction's Causes.Pérez Feo, MirnaRelación entre estado nutricional y características socioeconómicas en pre-escolares, Mérida, VenezuelaRelationship between nutritional status and socioeconomic characteristics in pre-school children, Mérida, VenezuelaHernández, MoreliaSalinas, Pedro JoséCambios motivacionales en pacientes afectados por infarto al miocardioMotivational changes in inpacients affected by a heart attack.Esqueda Torres, LuisMultivariate analysis to discriminate species of phlebotomine sandflies (Diptera:Psychodidae). Lutzomyia cayennensis and Lutzomyia yencanensisAnálisis multivariante para discriminar especies de flebotominos(Diptera:Psychodidae). Lutzomyia cayennensis y Lutzomyia yencanensisCazorla, DalmiroAñez Reverol, Nestor OswaldoMárquez, VíctorNieves, ElsaAlteraciones enzimáticas séricas en la hipervitaminosis K3 agudaSerum enzimatic alterations in the acute K3 hypervitaminosisVillavicencio M.,A.J.Somoza T., C.J.Tauil B.,E.Alarcón C.,O.M.Revisión de librosSalinas, Pedro JoséSemblanza. Dr. Eduardo Jorge Briese SerghieEscalante, [email protected]@ula.veNivel analíticosemestra
Update on Chagas disease in Venezuela - A review
The present article reviews the status of Chagas disease in Venezuela based on the detection of Trypanosoma cruzi infections both in referred patients with clinical presumptive diagnosis (1988-2002) and in individuals sampled from rural localities representative of the different geographical regions of the country (1995-2002). In the former group from 306 individuals examined, 174 (56.8%) were seropositive to T. cruzi; 73 (42%) in the acute phase with 52 (71%) showing blood circulating parasites, and from these 38% were children under 10 years old. The other 101 (58%) showed chronic infection at different degrees of cardiac complication. In addition, serologic examination of 3835 individuals from rural areas revealed 11.7% seroprevalence. From these, 8.5% (38/448) were children aged
from 0 to 10 years old. These figures suggest that Chagas disease may be re-emerging in Venezuela judging for the
active transmission detected during the last decade. The success of the Venezuelan anti-chagasic campaign during the last 40 years is evaluated in the frame of the present results. The epidemiological situation is discussed and recommendation to consider Chagas disease as a national priority is [email protected]@[email protected]