Resistencia de Aedes aegypti (diptera: culicidae) a insecticidas organofosforados y piretroides en la localidad de Orotina, Alajuela, Costa Rica / Resistance of Aedes aegypti (Diptera: Culicidae to organophosphate and pyrethroid insecticides in Orotina, Alajuela, Costa Rica

Objetivos: Determinar la resistencia de una cepa de Aedes. aegypti de Orotina a insecticidas organofosforados (temefós y malatión), y a piretroides (deltametrina, lambda cialotrina y cipermetrina). Métodos: La evaluación de la resistencia se efectuó mediante bioensayos larvarios. A partir de cada uno de los insecticidas se calculó la concentración letal 50% (CL50). También se calculó el factor de resistencia 50% (FR50) con respecto a la cepa Rockefeller, que sirvió como control susceptible. En casos de resistencia, la evaluación se repitió exponiendo previamente las larvas a butóxido de piperonilo (BP), S, S, S tributilfosforotritionato (DEF) y ácido etacrínico (AE) para establecer los mecanismos de detoxificación asociados con la resistencia. En cada caso se calculó un factor de sinergismo 50% (FS50). Resultados: La cepa Orotina mostró susceptibilidad a temefós, malatión, deltametrina y lambda cialotrina, pero mostró resistencia incipiente a cipermetrina (CL50= 0,01103 mg/L, FR50 = 5,32). Sólo el BP revertió la resistencia a este insecticida (FS50 =10,92), lo que representa un mecanismo de detoxificación asociado con el sistema citrocromo P450 monooxigenasa. Discusión: Aunque la cepa de Ae. aegyptide Orotina mostró resistencia a cipermetrina, existen otros insecticidas para los cuales fue susceptible, que brindan opciones a las autoridades de salud para su implementación en el control químico del vector. Conclusiones: El monitoreo de la resistencia es requerido para asegurar la efectividad de los insecticidas que se utilizan en el control químico.

Abstract Objectives: To determine the resistance to organophosphate (temephos and malathion) and pyrethroid (deltamethrin, lambda cyhalothrin, and cypermethrin) insecticides in a strain of Aedes aegypti from Orotina. Methods: The evaluation of the resistance was carried out by larval bioassays. Lethal concentration 50% (LC50) was calculated for each insecticide. A factor of resistance 50% (FR50) was also calculated with respect to the Rockefeller strain, which served as susceptible control. In cases of resistance, the evaluation was replicated by exposing the larvae to piperonyl butoxide (PB), S, S, S tributylphosphorotritionate (DEF), and ethacrynic acid (AE), in order to establish the detoxification mechanisms associated with the resistance. In these cases, a factor of synergism 50% (FS50) was also calculated. Results: The Orotina strain of Ae. aegyptiwas susceptible to temephos, malathion, deltamethrin and lambda cyhalothrin, but showed incipient resistance to cypermethrin (LC50 = 0.01103 mg/L, FR50 = 5.32). Only PB reversed the state of resistance (FS50 = 10.92), which suggests a detoxification mechanism associated with the citochrome P450 monooxygenase system. Discussion: Although the Ae. aegyptistrain from Orotina showed resistance to cypermethrin, it was susceptible to other insecticides, which can be used as alternative options for chemical control of the vector. Conclusions: Monitoring of resistance is required to ensure the effectiveness of insecticides used in chemical control.

Forage production and mineral composition of cactus intercropped with legumes and fertilized with different sources of manure / Produção de forragem e composição mineral da palma consorciada com leguminosas e adubada com diferentes fontes de esterco

ABSTRACT: The objective of this study was to evaluate the productive potential and mineral composition of the forage cactus IPA-Sertânia (Nopalea cochenillifera Salm Dyck). This species was analyzed both in monoculture and intercropped with leucaena [Leucaena leucocephala (Lam.) De Wit.] and gliricidia [Gliricidia sepium (Jacq. Steud.], and was assessed with different sources of manure (cattle, sheep, goat, and broiler litter) serving as fertilizer. The experiment was conducted at the Experimental Station of the Instituto Agronômico de Pernambuco in Caruaru, PE, Brazil. Treatments were allocated in a split-plot arrangement in a randomized complete block design, with four replications. Main plots consisted of cropping systems, while the split-plots were dedicated to manure sources. Cactus harvest was carried out after two years of regrowth. Response variables included both production and nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg) concentrations. No differences were observed for cactus production between the cropping systems, with an average value of 22.1Mg dry matter ha-1 2 years-1. In the intercropped systems, greater proximity to the legumes increased the production of the cactus in the treatments with the cattle and sheep manure, and increased the concentrations of P, K, and Mg, but not of N. The introduction of tree legumes, along with the application of manure, contributes to an increase in production and nutrient concentration of IPA-Sertânia cactus.

RESUMO: Objetivou-se avaliar o potencial produtivo e a composição mineral da palma forrageira IPA-Sertânia (Nopalea cochenillifera Salm Dyck), em cultivo isolado e consorciada com leucena [Leucaena leucocephala (Lam.) de Wit.] ou gliricídia [Gliricidia sepium (Jacq.) Steud.], e adubada com as fontes de esterco bovino, ovino, caprino e cama de frango. O experimento foi conduzido na Estação Experimental do Instituto Agronômico de Pernambuco - IPA, em Caruaru. O delineamento foi casualizado em blocos, em parcelas subdivididas, com quatro repetições. As parcelas foram representadas pelos sistemas de cultivo e as subparcelas pelas fontes de esterco. A colheita da palma foi realizada aos dois anos de crescimento e analisada quanto à produção e aos teores de nitrogênio (N), fósforo (P), potássio (K), cálcio (Ca) e magnésio (Mg). Não foram observadas diferenças de produção da palma entre os sistemas de cultivo, atingindo valor médio de 22,1t ha-1 2 anos-1 de matéria seca (MS). Nos sistemas consorciados, a maior proximidade com as leguminosas incrementou a produção da palma, nos tratamentos com os estercos bovino e ovino, e elevou os teores de P, K e Mg, mas não os teores de N. A introdução de leguminosas arbóreas, juntamente com a aplicação dos estercos, contribui para elevar a produção e os níveis de nutrientes da palma IPA-Sertânia.

Different resistance patterns of reference and field strains of Brucella abortus

The aim of this study was to evaluate the growth of the B. abortus reference strains and field isolates on media containing different inhibitor agents. Reference strains were seeded on tryptose agar containing: i-erythritol (1.0 mg/mL), fuchsin (20 μg/mL and 80 μg/mL), thionin (2.5 μg/mL and 10 μg/mL), rifampicin (200 μg/mL) and safranin O (200 μg/mL). Field isolates were tested only on media containing i-erythritol, rifampicin and thionin. Furthermore, each suspension was also inoculated on tryptose agar incubated in air, to test its ability to grow without CO2. Sensitivity to fuchsin was similar among reference strains evaluated. Growth of S19, 544 and 2308 but not RB51 were inhibited on media containing rifampicin. Medium with safranin O showed no inhibition for RB51, 544 and 2308, but it partially inhibited the S19 growth as well as medium containing i-erythritol. Treatment/control growth ratio for 2308 on tryptose agar containing thionin (2.5 μg/mL) was approximatelly 1.0, whereas S19 and RB51 showed 0.85 and 0.89 ratios, respectively. Growth of 544, S19 and RB51 but not 2308 was completely inhibited on medium with thionin (10 μg/mL). All field strains grew on medium containing i-erythritol, but were completelly inhibited by rifampicin. With exception of A1 (B. abortus biovar 3) all field isolates grew on medium with thionin, although some strains showed a treatment/control growth ratio of 0.75–0.80 (10 μg/mL). These results showed that tryptose agar with thionin, i-erythritol or rifampicin could be useful for differentiating vaccine, challenge and field strains of B. abortus.

Sobrecarga, apoyo social y autocuidado en cuidadores informales / Burden, social support and self-care in informal caregivers

Objetivo: Conocer el nivel de sobrecarga, el apoyo social percibido, la capacidad de agencia de autocuidado y otros factores relacionados, en cuidadores/as informales de pacientes dependientes de la comuna de Tomé, Chile. Material y método: estudio descriptivo. Muestra probabilística, sistemática y estratificada estuvo compuesta por 30 cuidadores/as informales, a quienes se les aplicaron cuatro instrumentos por medio de visitas domiciliarias: cuestionario de evaluación biosociodemográfica del cuidador informal principal, escala de sobrecarga de Zarit, Escala Multidimensional de Apoyo Social Percibido de Zimet y Escala de Apreciación de Agencia de Autocuidado (ASA). Resultados: Los cuidadores/as informales son: mujeres, adultas, con pareja, con educación básica incompleta, sin trabajo ni participación social y con percepción económica insuficiente, dedicando gran parte del día a cuidar, sin ayuda de terceros, con niveles de sobrecarga leve, escasa percepción de apoyo social y desarrollo de moderada capacidad de agencia de autocuidado. Conclusión: Los resultados emanados de esta investigación permiten colaborar en la generación de políticas públicas que apoyen a este grupo de interés vulnerable desde el punto de vista social y sanitario.

Objective: Knowing the level of burden, perceived social support, the ability of self-care agency and other factors related, in informal caregiver of dependant patients in the city of Tomé, Chile. Methods: Descriptive study. The systematic stratifed probabilistic sample consisted of 30 informal caregivers to whom four instruments were applied through home visits: bio sociodemographic questionnaire for the principal informal caregiver, Zarit Burden Scale, Multidimensional Scale of Perceived Social Support by Zimet and Appraisal of Self-care Agency Scale (ASA). Results: the informal caregivers are adult women, with partners, with incomplete primary education, no work or social participation and insufficient economic perception, devoting much of their day to care, without assistance from others, with levels of mild overload, poor perception of social support and moderate capacity of self-care. Conclusions: Results emerging from this research can cooperate in the generation of public policies to support this vulnerable group of interest from a social and health standpoint.

Uso do ensaio imunoenzimático e imunoblotting para detecção de imunoglobulinas contra Campylobacter fetus em muco cérvico-vaginal de fêmeas bovinas / The use of enzyme-linked immunosorbent assay and immunoblotting for the detection of Campylobacter fetus immunoglobulins in the cervico-vaginal mucus of female cattle

Foi padronizado um ensaio imunoenzimático do tipo indireto para detecção de imunoglobulina A (ELISA IgA) anti- Campylobacter fetus subp. venerealis em muco cérvico- vaginal bovino utilizando um extrato protéico de Campylobacter fetus subsp. venerealis produzido pelo método de extração ácida pelo tampão de glicina (0,2M; pH2,2). A média dos valores de densidade ótica (DO450) foi de 0,143±0,09. As bandas protéicas dos antígenos de Campylobacter fetus subsp. venerealis e de Campylobacter fetus subsp. fetus melhor reconhecidas pela IgA do muco cérvico- vaginal migraram em 42,6 kDa mas a proteina evidenciada em 93 kDa foi reconhecida exclusivamente pelo Campylobacter fetus subsp. venerealis. Os anticorpos presentes na amostra de muco vaginal testada no “immunoblotting” que apresentou resultado positivo no ELISA IgA, reconheceu antígenos de C. jejuni subsp. jejuni e C. fetus subsp. fetus.

An indirect enzyme-linked immunosorbent assay was developed to detect antigenspecific secretory IgA antibodies to Campylobacter fetus subsp. venerealis in bovine vaginal mucus with a protein extract of the Campylobacter fetus subsp. venerealis by the acid glycine extraction method. Mean optical density measurement (λ=450 nm) was 0.143±0.9. The most immunoreactive protein bands of the Campylobacter fetus subsp. venerealis or Campylobacter fetus subsp. fetus recognized by IgA in immunoblotting, using bovine vaginal mucus samples, migrate at 42.6 kDa. The protein that migrates at 93 kDa was recognized exclusively for C. fetus subsp. venerealis. A positive vaginal mucus sample of a cow from negative herd recognized antigens of C. jejuni subsp. jejuni e C. fetus subsp. fetus.

Antimicrobial susceptibility of Campylobacter sp strains isolated from calves with and without diarrhea in Minas Gerais state, Brazil

The antimicrobial susceptibility of 25 Campylobacter sp strains isolated from calves with and without diarrhea - 7 C. coli, 16 C. fetus and 2 C. jejuni was studied by the disk diffusion method. Eleven antimicrobial agents were tested amikacin, ampicillin, kanamycin, chloramphenicol, erythromycin, gentamicin, neomycin, nitrofurantoin, penicillin G, tetracycline and sulfamethoxazole-trimethoprim. All Campylobacter sp strains were susceptible to amikacin, ampicillin, chloramphenicol, erythromycin, gentamicin, neomycin and nitrofurantoin. Three strains were moderately susceptible to kanamycin (2 C. coli and 1 C. fetus). All the strains were resistant to penicillin G. Two C. fetus strains were moderately susceptible to sulfamethoxazole-trimethoprim and 1 C. coli, 9 C. fetus and 2 C. jejuni strains were resistant. Two C. fetus strains were moderately susceptible to tetracycline and 3 C. coli, 2 C. fetus and 1 C. jejuni strains were resistant. Eleven strains showed multidrug resistance (2 C. coli, 8 C. fetus and 1 C. jejuni). There was no correlation between resistance of Campylobacter sp strains to antimicrobials and the occurrence of diarrhea in calves. The frequency of resistance and, most importantly, multi drug resistance found among Campylobacter sp strains isolated from calves in Minas Gerais, Brazil, were high and the patterns of resistance observed are related to the antimicrobials agents most largely used in cattle in Brazil.

Foi estudado o perfil de susceptibilidade aos antimicrobianos de 25 amostras de Campylobacter sp isoladas de bezerros com e sem diarréia (7 C. coli, 16 C. fetus e 2 C. jejuni). Foram testados pelo método de difusão 11 agentes antimicrobianos: amicacina, ampicilina, canamicina, cloranfenicol, eritromicina, gentamicina, neomicina, nitrofurantoína, penicilina G, tetraciclina e sulfametoxazole-trimetoprim. Todas as amostras de Campylobacter sp foram susceptíveis a amicacina, ampicilina, cloranfenicol, eritromicina, gentamicina, neomicina e nitrofurantoína. Três amostras foram moderadamente sensíveis à canamicina (2 C. coli e 1 C. fetus). Todas as amostras foram resistentes à penicilina G. Duas amostras de C. fetus foram moderadamente sensíveis a sulfametoxazole-trimetoprim e 1 C. coli, 9 C. fetus e 2 C. jejuni foram resistentes. Duas amostras de C. fetus foram moderadamente sensíveis à tetraciclina e 3 de C. coli, 2 de C. fetus e 1 de C. jejuni foram resistentes. Onze amostras apresentaram multirresistência (2 C. coli, 8 C. fetus e 1 C. jejuni). Não houve correlação entre resistência de amostras de Campylobacter sp aos antimicrobianos e a ocorrência de diarréia nos bezerros. A frequência de resistência e, principalmente, a multirresistência encontradas nas amostras Campylobacter sp isoladas de bezerros em Minas Gerais, Brasil, foram altas. O perfil de resistência de amostras de Campylobacter sp observado está relacionado aos agentes antimicrobianos mais utilizados em bovinos no Brasil.

Experiencia en estudios de SPECT de perfusión miocárdica en población pediátrica / Experience in studies of myocardial perfusion SPECT in the pediatric population

Los estudios isotópicos cardíacos en niños tienen distinto enfoque que en adultos, en quienes la pesquisa y el seguimiento de la enfermedad coronaria (EC) juegan un papel importante y bien reconocido. En general, las causales de solicitud corresponden principalmente a patología de tipo congénito o inflamatorio. La enfermedad de Kawasaki (EK) (vasculitis) que produce alteraciones coronarias severas puede ser fácilmente evaluada no invasivamente con los marcadores de perfusión. En esta presentación se discuten las principales causas de requerimiento de estudios de perfusión y viabilidad miocárdica en pediatría y se presenta la experiencia en este campo del Hospital Clínico de la Universidad de Chile, con 18 exámenes SPECT en 13 niños entre 9 meses y 14 años, durante los últimos 6 años.