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1.
Braz. j. biol ; 82: 1-8, 2022. graf, tab, ilus
Article in English | LILACS, VETINDEX | ID: biblio-1468449

ABSTRACT

Aedes aegypti is a culicide that has gained relevance over the years due to its ability to transmit various viruses that cause diseases in humans that all the years cause high mortality rates in the world population. The main problem is that Ae. aegypti has managed to establish and maintain a close relationship with humans and their habitat, which is why the search for alternatives to control vector populations becomes imperative. The objective of the present work was to study the effects of two Beauveria bassiana strains on Aedes aegypti. Third instar larvae of Ae. aegypti in 250 mL plastic containers were inoculated with the GHA and NB3 strains at different concentrations (1.5 × 104, 1.5× 105, 1.5 × 106 and 1.5 × 107 conidia/mL). The NB3 strain presented highest mortality values with 63% in the highest concentration i.e., 1.5 × 107, while for the GHA strain the highest mortality value was 30.7% at the same concentration. The results showed significant difference in mortality with respect to the strain and days post treatment (P = 0.0001), but not with respect to the conidial concentration (P = 0.634). The average mortality of larvae per day for the NB3 for different concentrations ranged from 20 to 25 larvae per day, while for the GHA daily mortality ranged from 5 to 12 larvae. In post-treatment mortality, the highest mortality was recorded in the third stage larvae for the NB3, while for GHA the highest percentage mortality was observed in individuals who managed to reach the adult state. The findings of the current research depicted the noteworthy role of B. bassiana for the management of an important vector of human disease.


O Aedes aegypti é um culicida que vem ganhando relevância ao longo dos anos devido à sua capacidade de transmitir diversos vírus causadores de doenças em humanos que ao longo dos anos ocasionam altas taxas de mortalidade na população mundial. O principal problema é que Ae. aegypti tem conseguido estabelecer e manter uma relação próxima com o homem e seu habitat, por isso a busca por alternativas para o controle das populações de vetores torna-se imperativa. O objetivo do presente trabalho foi estudar os efeitos de duas cepas de Beauveria bassiana sobre Ae. aegypti. Larvas de terceiro instar de Ae. aegypti em recipientes plásticos de 250 mL foram inoculados com as cepas GHA e NB3 em diferentes concentrações (1.5 × 104, 1.5 × 105, 1.5 × 106 e 1.5 × 107 conídios/mL). A cepa NB3 apresentou os maiores valores de mortalidade com 63% na concentração mais alta, ou seja, 1.5 × 107, enquanto para a cepa GHA o maior valor de mortalidade foi 30.7% na mesma concentração. Os resultados mostraram diferença significativa na mortalidade com relação à cepa e dias pós-tratamento (P = 0.0001), mas não com relação à concentração de conídios (P = 0.634). A mortalidade média de larvas por dia para o NB3 para diferentes concentrações variou de 20 a 25 larvas por dia, enquanto para o GHA a mortalidade diária variou de 5 a 12 larvas. Na mortalidade pós-tratamento, a maior mortalidade foi registrada nas larvas de terceiro estágio para o NB3, enquanto para o GHA o maior percentual de mortalidade foi observado em indivíduos que conseguiram atingir o estado adulto. Os resultados da pesquisa atual retratam o papel notável de B. bassiana no manejo de um importante vetor de doenças humanas.


Subject(s)
Animals , Aedes , Beauveria/pathogenicity , Pest Control/methods , Arbovirus Infections/veterinary
2.
Braz. j. biol ; 822022.
Article in English | LILACS-Express | LILACS, VETINDEX | ID: biblio-1468636

ABSTRACT

Abstract Aedes aegypti is a culicide that has gained relevance over the years due to its ability to transmit various viruses that cause diseases in humans that all the years cause high mortality rates in the world population. The main problem is that Ae. aegypti has managed to establish and maintain a close relationship with humans and their habitat, which is why the search for alternatives to control vector populations becomes imperative. The objective of the present work was to study the effects of two Beauveria bassiana strains on Aedes aegypti. Third instar larvae of Ae. aegypti in 250 mL plastic containers were inoculated with the GHA and NB3 strains at different concentrations (1.5 × 104, 1.5× 105, 1.5 × 106 and 1.5 × 107 conidia/mL). The NB3 strain presented highest mortality values with 63% in the highest concentration i.e., 1.5 × 107, while for the GHA strain the highest mortality value was 30.7% at the same concentration. The results showed significant difference in mortality with respect to the strain and days post treatment (P = 0.0001), but not with respect to the conidial concentration (P = 0.634). The average mortality of larvae per day for the NB3 for different concentrations ranged from 20 to 25 larvae per day, while for the GHA daily mortality ranged from 5 to 12 larvae. In post-treatment mortality, the highest mortality was recorded in the third stage larvae for the NB3, while for GHA the highest percentage mortality was observed in individuals who managed to reach the adult state. The findings of the current research depicted the noteworthy role of B. bassiana for the management of an important vector of human disease.


Resumo O Aedes aegypti é um culicida que vem ganhando relevância ao longo dos anos devido à sua capacidade de transmitir diversos vírus causadores de doenças em humanos que ao longo dos anos ocasionam altas taxas de mortalidade na população mundial. O principal problema é que Ae. aegypti tem conseguido estabelecer e manter uma relação próxima com o homem e seu habitat, por isso a busca por alternativas para o controle das populações de vetores torna-se imperativa. O objetivo do presente trabalho foi estudar os efeitos de duas cepas de Beauveria bassiana sobre Ae. aegypti. Larvas de terceiro instar de Ae. aegypti em recipientes plásticos de 250 mL foram inoculados com as cepas GHA e NB3 em diferentes concentrações (1.5 × 104, 1.5 × 105, 1.5 × 106 e 1.5 × 107 conídios/mL). A cepa NB3 apresentou os maiores valores de mortalidade com 63% na concentração mais alta, ou seja, 1.5 × 107, enquanto para a cepa GHA o maior valor de mortalidade foi 30.7% na mesma concentração. Os resultados mostraram diferença significativa na mortalidade com relação à cepa e dias pós-tratamento (P = 0.0001), mas não com relação à concentração de conídios (P = 0.634). A mortalidade média de larvas por dia para o NB3 para diferentes concentrações variou de 20 a 25 larvas por dia, enquanto para o GHA a mortalidade diária variou de 5 a 12 larvas. Na mortalidade pós-tratamento, a maior mortalidade foi registrada nas larvas de terceiro estágio para o NB3, enquanto para o GHA o maior percentual de mortalidade foi observado em indivíduos que conseguiram atingir o estado adulto. Os resultados da pesquisa atual retratam o papel notável de B. bassiana no manejo de um importante vetor de doenças humanas.

3.
Braz. j. biol ; 82: e237789, 2022. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1249272

ABSTRACT

Aedes aegypti is a culicide that has gained relevance over the years due to its ability to transmit various viruses that cause diseases in humans that all the years cause high mortality rates in the world population. The main problem is that Ae. aegypti has managed to establish and maintain a close relationship with humans and their habitat, which is why the search for alternatives to control vector populations becomes imperative. The objective of the present work was to study the effects of two Beauveria bassiana strains on Aedes aegypti. Third instar larvae of Ae. aegypti in 250 mL plastic containers were inoculated with the GHA and NB3 strains at different concentrations (1.5 × 104 , 1.5× 105 , 1.5 × 106 and 1.5 × 107 conidia/mL). The NB3 strain presented highest mortality values with 63% in the highest concentration i.e., 1.5 × 107 , while for the GHA strain the highest mortality value was 30.7% at the same concentration. The results showed significant difference in mortality with respect to the strain and days post treatment (P = 0.0001), but not with respect to the conidial concentration (P = 0.634). The average mortality of larvae per day for the NB3 for different concentrations ranged from 20 to 25 larvae per day, while for the GHA daily mortality ranged from 5 to 12 larvae. In post-treatment mortality, the highest mortality was recorded in the third stage larvae for the NB3, while for GHA the highest percentage mortality was observed in individuals who managed to reach the adult state. The findings of the current research depicted the noteworthy role of B. bassiana for the management of an important vector of human disease.


O Aedes aegypti é um culicida que vem ganhando relevância ao longo dos anos devido à sua capacidade de transmitir diversos vírus causadores de doenças em humanos que ao longo dos anos ocasionam altas taxas de mortalidade na população mundial. O principal problema é que Ae. aegypti tem conseguido estabelecer e manter uma relação próxima com o homem e seu habitat, por isso a busca por alternativas para o controle das populações de vetores torna-se imperativa. O objetivo do presente trabalho foi estudar os efeitos de duas cepas de Beauveria bassiana sobre Ae. aegypti. Larvas de terceiro instar de Ae. aegypti em recipientes plásticos de 250 mL foram inoculados com as cepas GHA e NB3 em diferentes concentrações (1.5 × 104, 1.5 × 105, 1.5 × 106 e 1.5 × 107 conídios/mL). A cepa NB3 apresentou os maiores valores de mortalidade com 63% na concentração mais alta, ou seja, 1.5 × 107, enquanto para a cepa GHA o maior valor de mortalidade foi 30.7% na mesma concentração. Os resultados mostraram diferença significativa na mortalidade com relação à cepa e dias pós-tratamento (P = 0.0001), mas não com relação à concentração de conídios (P = 0.634). A mortalidade média de larvas por dia para o NB3 para diferentes concentrações variou de 20 a 25 larvas por dia, enquanto para o GHA a mortalidade diária variou de 5 a 12 larvas. Na mortalidade pós-tratamento, a maior mortalidade foi registrada nas larvas de terceiro estágio para o NB3, enquanto para o GHA o maior percentual de mortalidade foi observado em indivíduos que conseguiram atingir o estado adulto. Os resultados da pesquisa atual retratam o papel notável de B. bassiana no manejo de um importante vetor de doenças humanas.


Subject(s)
Humans , Animals , Aedes , Beauveria , Disease Vectors , Mosquito Vectors , Larva
4.
Ludovica pediátr ; 24(1): 6-14, Ene.-Jul.2021.
Article in Spanish | LILACS, Redbvs, BINACIS | ID: biblio-1293217

ABSTRACT

Introducción:La transmisión congénita de Trypanosoma cruzi constituye, en la actualidad, la vía que genera mayor cantidad de nuevos casos de infección aguda. El diagnóstico y tratamiento temprano aseguran una elevada probabilidad de cura parasitológica. El objetivo del trabajo fue evaluar el seguimiento de potenciales casos de Chagas Congénito, estimar la tasa de transmisión materno-fetal y la capacidad diagnóstica del microhematocrito. Materiales y métodos: Se realizó un estudio descriptivo transversal sobre hijos de mujeres con Chagas, que concurrieron al Laboratorio Central del H.I.A.E.P. Sor María Ludovica durante abril 2013-febrero 2019. Los niños fueron estudiados por microhematocrito y pruebas serológicas. Los resultados se obtuvieron del Sistema Informático de Laboratorio de Wiener®. Resultados: En el período de tiempo evaluado, fueron estudiados por microhematocrito un total de 268 niños (edad promedio= 2,35 meses), obteniéndose 16 resultados positivos. De los 252 niños con microhematocrito negativo, 58 fueron seguidos por pruebas serológicas hasta el año de vida, obteniéndose 3 resultados positivos. Se evidenció una pérdida de seguimiento serológico del 77%. La tasa de transmisión congénita estimada fue del 6,9% y el porcentaje de detección diagnóstica de la técnica directa, del 84,2%. Conclusión: La búsqueda de infección congénita en hijos de mujeres con Chagas, y su seguimiento hasta el año de vida, resulta esencial para lograr la detección y tratamiento temprano de nuevos casos. Sin embargo, la pérdida de seguimiento de potenciales casos de Chagas Congénito resulta alarmante. Esto enfatiza la necesidad de plantear estrategias sólidas para mejorar la aplicación del algoritmo diagnóstico


Introduction:Congenital Trypanosoma cruzi transmission is currently the route that generates the largest number of new cases of acute infection. Early diagnosis and treatment ensure a high probability of parasitological cure. The aim of this article was to evaluate the follow-up of possible cases of Congenital Chagas, to estimate the maternal-fetal transmission rate and the diagnostic capacity of microhematocrit. Materials and methods: A cross-sectional descriptive study was carried out on children born from Chagasic women, who attended the Central Laboratory of the H.I.A.E.P Sor María Ludovica during April 2013-February 2019. The children were studied by microhematocrit and serological tests. The results were obtained from the Wiener® Laboratory Information System. Results: In the evaluated time period, a total of 268 children (mean age = 2.35 months) were studied by microhematocrit, obtaining 16 positive results. Among the 252 children with negative microhematocrit, 58 were followed by serological tests up to one year of life, obtaining 3 positive results. A 77% loss of serological follow-up was evidenced. The estimated congenital transmission rate was 6.9% and the percentage of diagnostic detection of the direct technique was 84.2%. Conclusion: The search for congenital infection in children born from Chagasic women, and its follow-up until one year of life, is essential to achieve the early detection and treatment of new cases. However, the loss of follow-up of potential cases of Congenital Chagas is alarming. This emphasizes the need to propose solid strategies to improve the application of the diagnostic algorithm


Subject(s)
Infant , Child, Preschool , Serologic Tests , Chagas Disease , Diagnosis
5.
Med. infant ; 22(3): 219-225, Sept.2015. tab, ilus
Article in Spanish | LILACS | ID: biblio-906643

ABSTRACT

Objetivos: 1) Analizar las reconsultas (RC) de pacientes a las 72 horas de su primera consulta en el Servicio de Emergencias Pediatría (SEP) de un hospital materno infantil del conurbano bonaerense. 2) Comparar las reconsultas entre dos periodos, luego de implementar mejoras en los procesos asistenciales y de contrarreferencia. Materiales y Metodos: Diseño: retrospectivo, observacional y transversal. Criterios de inclusión: pacientes de 30 días a 15 años de edad, que reconsultaron en el SEP del 01/01 al 31/03 de los años 2010 y 2014. Resultados: Las consultas que se atendieron en el periodo de estudio fueron: 14.003 en 2010 y 13.011 en 2014. Los diagnósticos más frecuentes fueron: infección respiratoria aguda alta (19.2%), fiebre (13%) y diarrea/ gastroenteritis (13.3%). Hubo 7.11% (n=966) de RC en el 2010 y 12.21% (n=1589) en el 2014. La mediana de edad de los pacientes con RC fue 24 meses en ambos años. Los motivos de RC más frecuentes fueron: persistencia de los síntomas (41% y 53.67%); progresión de la enfermedad (25% y 11.43%); otros diagnósticos nuevos (14.07% y 19.5%) y control (14% y 8.3%). Las RC de los domiciliados en San Isidro fueron 72.97% (n=694) en el 2010 y 69.32% (n=1071) en el 2014 del total de RC. La disminución de las RC observada al comparar ambos períodos es estadísticamente no significativa. (Pearson chi2 2.4506, p = 0.117). Conclusiones: 1) Los principales motivos de consulta fueron fiebre, diarrea y patología de la vía aérea superior. 2) Las RC dentro de las primeras 72 horas fueron 7% en 2010 y 12.9% en 2014. 3) La mayoría de los niños que concurren por RC lo hacen por la persistencia de síntomas de procesos que revisten poca gravedad. 4) Hubo una leve disminución, estadísticamente no significativa, de la RC de los pacientes domiciliados en San Isidro (AU)


Aims: 1) To analyze second consultations (SC) in patients within 72 hours of the first consultation at the Pediatric Emergency Department (PED) of a mother-and-child hospital in Greater Buenos Aires. 2) To compare SC between two time periods, after implementing a program of care and counter-referral. Material and Methods: Study design: a retrospective, observational, and cross-sectional study was conducted. Inclusion criteria: patients between 30 days of life and 15 years of age, who consulted at the PED between 01/01 and 31/03 from 2010 to 2014. Results: Patients seen during the study period were: 14,003 in 2010 and 13,011 in 2014. The most common diagnoses were: Acute upper respiratory infection (19.2%), fever (13%) and diarrhea/gastroenteritis (13.3%). SC were 7.11% (n=966) in 2010 and 12.21% (n=1589) in 2014. Median age of patients with a SC was 24 months in both years. Most common reasons for SC were persistent symptoms (41% and 53.67%); disease progression (25% and 11.43%); new diagnosis (14.07% and 19.5%) and control (14% and 8.3%). Home visits for SC in San Isidro were 72.97% (n=694) in 2010 and 69.32% (n=1071) in 2014 of all SC. The decrease in SC when comparing both periods was not statistically significant (Pearson chi2 2.4506, p = 0.117). Conclusions: 1) The main reasons for consult were fever, diarrhea, and upper airway infections. 2) SC within 72 hours were 7% in 2010 and 12.9% in 2014. 3) The majority of childrenwho were seen in a SC had persistent symptoms that were not severe. 4) A slight decrease, that was not statistically significant, was observed in SC of patients seen in the area of San Isidro (AU)


Subject(s)
Humans , Infant , Child, Preschool , Child , Adolescent , Emergency Service, Hospital , Patient Readmission , Quality Indicators, Health Care , Cross-Sectional Studies , Observational Study , Retrospective Studies
6.
Mem. Inst. Oswaldo Cruz ; 103(8): 839-842, Dec. 2008. tab
Article in English | LILACS | ID: lil-502307

ABSTRACT

Studies were carried out to evaluate the efficacy of the growth regulator, triflumuron (TFM) (Starycide® sc 480 Bayer), for disrupting the development of Rhodnius prolixus fifth-instar nymph by oral, topical or continuous treatment. All treatments were able to induce high levels of mortality, delay development and molt inhibition. Oral treatment induced molt inhibition in all insects that survived at doses of 0.25, 0.50 and 5.0 mg/mL of a blood meal. The highest levels of both mortality in 24 h and molt inhibition were always observed after topical treatment. The lowest doses needed to obtain considerable biological effects were always observed after continuous treatment. In this way, the highest levels of mortality within 30 days were detected after continuous treatment, which also induced an extended inter-molting period, a lower number of over-aged nymphs and the highest level of molting in nymphs that survived. Moreover, the effects of TFM on insects were often displayed in a dose response manner. These results indicate that TFM acts as a potent growth inhibitor of R. prolixus nymphs and has the potential to be used in integrated vector control programs against hematophagous triatomine species.


Subject(s)
Animals , Male , Benzamides/pharmacology , Insecticides/pharmacology , Rhodnius/drug effects , Dose-Response Relationship, Drug , Nymph/drug effects , Nymph/growth & development , Rhodnius/growth & development , Time Factors
7.
Mem. Inst. Oswaldo Cruz ; 99(8): 815-822, dez. 2004. ilus
Article in English | LILACS | ID: lil-393762

ABSTRACT

The effects of blood components, nerve-cord severance, and ecdysone therapy on the posterior midgut epithelial cells of 5th-instar Rhodnius prolixus nymphs 10 days after feeding were analyzed by transmission electron microscopy. Cutting the nerve-cord of the blood-fed insects partially reduced the development of microvilli and perimicrovillar membranes (PMM), and produced large vacuoles and small electrondense granules; insects fed on Ringer's saline diet exhibited well developed microvilli and low PMM production; swolled rough endoplasmatic reticulum and electrondense granules; Ringer's saline meal with ecdysone led to PMM development, glycogen particles, and several mitochondria in the cytoplasm; epithelial cells of the insects fed on Ringer's saline meal whose nerve-cord was severed showed heterogeneously distributed microvilli with reduced PMM production and a great quantity of mitochondria and glycogen in the cytoplasm; well developed microvilli and PMM were observed in nerve-cord severed insects fed on Ringer's saline meal with ecdysone; Ringer's saline diet containing hemoglobin recovered the release of PMM; and insects fed on human plasma showed slightly reduced PMM production, although the addition of ecdysone in the plasma led to a normal midgut ultrastructural organization. We suggest that the full development of microvilli and PMM in the epithelial cells depends on the abdominal distension in addition to ingestion of hemoglobin, and the release of ecdysone.


Subject(s)
Animals , Male , Blood , Ecdysone , Microvilli , Rhodnius , Intestines , Microscopy, Electron , Nymph
8.
Rev. bras. farmacogn ; 12(supl.1): 70-71, 2002. ilus
Article in Portuguese | LILACS | ID: lil-528757

ABSTRACT

Ácido oleanólico apresenta no barbeiro Rhodnius prolixus, vetor da doença de Chagas, toxicidade dosedependente e drástica inibição da muda nas doses de 1, 10 e 100 mg/ml. Eugenol induz uma letargia que persiste por vários dias, apresenta forte fagorrepelência, toxicidade média e inibição total da muda nas doses de 10 e 100 mg/ml.

9.
Biocell ; 25(1): 23-27, Apr. 2001.
Article in English | LILACS | ID: lil-335888

ABSTRACT

The ability of Triatoma infestans ovarian follicles to synthesize a very high-density lipoprotein (VHDL) has been examined by immunohistochemical methods. This kind of lipoprotein can be envisaged as a storage hexameric protein present in the hemolymph of some insect species. VHDL immunoreactivity is observed in oocytes at different stages of maturation. The antigen is present in the oocyte cytoplasm as well as in the follicular epithelial cells. The immunopositive reaction in the apical surface of follicle cells suggests both a VHDL synthesis and a secretion process. Furthermore, VHDL seems to be stored into oocyte in yolk granules. On the contrary, no immunopositive reaction is observed in the intracellular spaces between follicle cells, suggesting that VHDL is not incorporated from hemolymph into the oocyte.


Subject(s)
Animals , Female , Lipoproteins, HDL/analysis , Insect Proteins/analysis , Triatoma , Ovarian Follicle/chemistry , Ovarian Follicle/cytology , Hemolymph , Immunohistochemistry , Lipoproteins, HDL/isolation & purification , Oocytes
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