ABSTRACT. This work aimed to improve reproductive maturation in two penaeoid species (Artemesia longinaris and Pleoticus muelleri) by using carotenes added in artificial feeds and comparing antioxidant activity and carotenoids profiles. Immature females were kept for 45 days at salinity 33, temperature at 18°C, pH 7, 12:12 h photoperiod, ammonium <0.2mg L−1 and seawater exchanged at 100% per day. Feeding regimes consisted of 50% fresh frozen ingredients (clam muscle and squid mantle) and 50% dry pellets. For each species, three pelletized feeds were tested, one as a control (C) and two supplemented each one with 300 mg astaxanthin (A) and β-carotene (B) kg−1 of diet. At the end of the trials, ovaries, midgut gland, and integument were sampled. In both species, the addition of carotenoids improved ovarian development: 100% of females fed A or B diets were mature, but of the females fed with diet C only 75% (P. muelleri) and 64% (A. longinaris) matured. Ovaries of mature females exhibited the highest concentration of carotenoids. The abundance of free astaxanthin regarding total carotenes, suggests that excess of free astaxanthin could be biotransformed to esterified astaxanthin. The scavenging properties were evaluated against the stable 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical by electron resonance spectroscopy (EPR). For all feed treatments, the extracts exhibited strong DPPH scavenging activity, without significant differences among them.

Water-soluble extracts from seaweeds Macrocystis pyrifera (M) and Undaria pinnatifida (U) were prepared to use the polysaccharide bioactive fraction as functional food. Chemical analysis showed that the main components of both extracts were mannitol and fucoidans. Also in both cases minor amounts of rhamnose, glucose, xylose and arabinose were determine. Content of fucose+galactose was higher in U. pinnatifida (8.7%) than in M. pyrifera (5.9%). Extracts were used as feed additive to Artemesia longinaris at inclusion levels of 1 and 2% (M1 and M2; U1 and U2), a diet without extract was used as control. Radical scavenging activities were estimated for two extracts and for midgut gland samples of experimental animals. Scavenging activity was detected in both extracts, the signal decayed to 50 and 62% in 18 min for U. pinnatifida and M. pyrifera, respectively. After 30 days of feeding, results did not show variation of survival, but growth was improved in animals fed with U1 and U2. Supplementation with 1 and 2% of U. pinnatifida showed similar quenching capacity of homogenates than those fed with M2 with a rapid 1,1-diphenylpicrylhydrazyl (DPPH) decay at 2 min of reaction. Recommended concentration for culture A. longinaris is 2%, as it is that produce the best antioxidant capacity, although the growth performance was improved also significantly only with U. pinnatifida extract.

Apanteles nr. Aristoteliae (Viereck) (Hymenoptera: Braconidae) is an endoparasitoid of the leafroller Amorbia sp. (Lepdidoptera: Tortricidae) larvae. In this study, the life cycle, parasitism, sex ratio, and longevity of adults of this parasitoid were determined under laboratory conditions (22 ± 2 ºC, 60 ± 5% relative humidity, and a photoperiod of 16:8h [light:dark]). The life cycle of this parasitoid was 42.45 ± 0.76 days. The duration of development stages of egg-larva, pupa and adult was 14.04 ± 0.05, 9.22 ± 0.07, and 19.36 ± 0.74 days, respectively. Each A. nr. aristoteliae female parasitized 73.33 ± 7.55 Amorbia sp. larvae. The sex ratio of F1 generation was 95.1% males (n = 912). Longevity of adults was significantly different (U = 564, P = 0.01) between mated males (27 ± 2.55 days) and virgins (19.75 ± 0.70 days) but not (U = 182, P = 0.3) between mated females that were exposed to parasitization during all its life (26.4 ± 2.88 days), and virgins (23.13 ± 1.4 days). In order to obtain a better understanding about life parameters of A. nr. aristoteliae, future studies that include different rearing conditions (e.g., temperature and space) are needed.

Apanteles nr. aristoteliae (Viereck) (Hymenoptera: Braconidae) es un endoparasitoide de larvas del enrollador de las hojas Amorbia sp. (Lepidoptera: Tortricidae). En este estudio se determinó, bajo condiciones de laboratorio (22 ± 2 ºC, 60 ± 5% de humedad relativa y un fotoperiodo de 16:8 h [luz: oscuridad]) el ciclo de vida, parasitismo, proporción sexual y longevidad de adultos de este parasitoide. La duración del ciclo de vida fue de 42.45 ± 0.76 días. El tiempo de desarrollo de los estados de huevo-larva, pupa y adulto fue de 14.04 ± 0.05, 9.22 ± 0.07 y 19.36 ± 0.74 días, respectivamente. A lo largo de toda su vida, cada hembra de A. nr. aristoteliae parasitó 73.33 ± 7.55 larvas del enrollador de las hojas Amorbia sp. La proporción sexual de la generación F1 fue de 95.1% machos (n = 912). La longevidad de los adultos fue significativamente distinta (U = 564, P = 0.01) entre los machos apareados (27 ± 2.55 días) y vírgenes (19.75 ± 0.70 días), pero no (U = 182, P = 0.3) entre las hembras apareadas y que fueron sometidas a parasitación durante toda su vida (26.4 ± 2.88 días) y vírgenes (23.13 ± 1.4 días). Con el fin de obtener un mejor conocimiento de los parámetros de vida del parasitoide A. nr. aristoteliae, es necesario realizar futuros estudios que incluyan diferentes condiciones de cría (ej., temperatura y espacio).

We standardized a solid-phase enzyme-linked immunosorbent assay (ELISA) in order to study the presence of Trypanosoma cruzi antibodies in asymptomatic persons who live in an area of Nicaragua endemic for Chagas' disease. The test was standardized to analyze filter-paper blood samples, which are easy to transport. In the first phase of our investigation, ELISA was used to study 18 samples of total serum and 18 eluates of blood from patients with chronic Chagas' disease; 30 samples of serum and 30 eluates of blood from healthy people, used as negative controls; and 14 samples of serum and 14 eluates of blood from patients with cutaneous or visceral leishmaniasis, which were used to study cross-reactions. Both with the total-serum and the blood-eluate samples, the ELISA test provided 100% sensitivity and 90% specificity. Cross-reactions in the patient samples were observed only with visceral leishmaniasis. The second phase of our investigation was a population study that included eight rural communities in the area of Somoto, Nicaragua. Through random sampling, filter-paper blood samples were collected from 2 434 people (1 335 men and 1 099 women) from the communities of Aguas Calientes, El Brocal, La Manzana, Las Playas, Los Canales, Santa Isabel, Santa Rosa, and Santa Teresa. Studied by ELISA and by indirect immunofluorescence (IIF), the samples included 260 found seropositive by ELISA (10.7%), of which 207 were positive according to IIF (8.5%). With both techniques, the majority of seropositives were among women, but the difference between men and women was not statistically significant. There was a high level of agreement between the results obtained with the two techniques. There was an upward trend with age, with 5.4% of those found seropositive by ELISA being persons 10 years of age or younger and 42.7% of those found seropositive being older than 50. The vast majority of the individuals analyzed were asymptomatic.

Se estandarizó un inmunoensayo enzimático en fase sólida (ELISA) para estudiar la presencia de anticuerpos contra Trypanosoma cruzi en personas asintomáticas que viven en un área endémica de enfermedad de Chagas en Nicaragua. El ensayo fue estandarizado para el análisis de muestras de sangre colectadas en papel de filtro como método simple de transporte de muestras de sangre. Se realizó un estudio previo en el que se estudiaron por ELISA 18 muestras de suero total y 18 eluidos de sangre de pacientes con enfermedad de Chagas crónica, 30 muestras de suero y 30 eluidos de sangre de personas sanas que se utilizaron como controles negativos y 14 muestras de suero y 14 eluidos de sangre de pacientes con leishmaniasis cutánea o visceral que se utilizaron para los estudios de reacciones cruzadas. Tanto con el suero total como con los eluidos de sangre, la prueba de ELISA proporcionó una sensibilidad de 100% y una especificidad de 90%; solo se observaron reacciones cruzadas con las muestras de pacientes con leishmaniasis visceral. El estudio poblacional incluyó a ocho comunidades rurales de Somoto, Nicaragua. Mediante un muestreo al azar se colectaron muestras de sangre en papel de filtro a 2 434 personas (1 335 del sexo masculino y 1 099 del sexo femenino) de las comunidades de Aguas Calientes, La Manzana, Los Canales, Santa Rosa, Las Playas, El Brocal, Santa Isabel y Santa Teresa. Las muestras fueron estudiadas por ELISA e inmunofluorescencia indirecta (IFI) encontrándose un total de 260 seropositivos por ELISA (10,7%), 207 de los cuales fueron también positivos por IFI (8,5%). La mayoría de los sueros seropositivos correspondieron a personas del sexo femenino con ambas técnicas, pero la diferencia entre hombres y mujeres no fue estadísticamente significativa. Los resultados obtenidos con ambas técnicas mostraron una excelente concordancia. Con respecto a la edad se observó una curva ascendente, con 5,4% de seropositivos por ELISA en individuos de 0-10 años y 42,7% en mayores de 50 años. La vasta mayoría de los individuos analizados fueron asintomáticos.

This study describes which antigens of Fasciola hepatica are present in the feces of patients with chronic fascioliasis and in the feces of rats infected experimentally with F. hepatica metacercariae. Using a Western blot assay technique with hyperimmune serum obtained from excretory-secretory antigens of adult F. hepatica, we found in the patients' feces antigens of possible diagnostic interest, with molecular weights of 14, 19, 20, 23, 25, 32, 46, 51, and 62 kilodaltons (kDa). In addition, we showed that the peptides of 14, 20, 23, and 51 kDa are also recognized by the majority of the sera from chronic patients. We used affinity chromatography to purify the antigens present in the feces of rats that had been infected for 6 to 12 weeks, using ES78 monoclonal antibody bound to CNBr-activated Sepharose 4B. Through that approach, we identified six polypeptides, of 11, 14, 26, 32, 47, and 51 kDa; three more polypeptides, of 17, 24, and 66 kDa, could only be identified in the feces of rats that had been infected for 10 to 12 weeks. Our results suggest that these polypeptides could be antigens common to both parasitic stages. This is particularly true for the polypeptides of 14, 24, 26, and 51 kDa, because they reacted with the immune sera, the human sera, and the ES78 monoclonal antibody. These polypeptides could be important markers for acute and chronic fascioliasis.

En el presente estudio se describen cuáles son los antígenos de Fasciola hepatica que están presentes en las heces de pacientes con fascioliasis crónica y de ratas infectadas experimentalmente con metacercarias de F. hepatica. Mediante el empleo de la técnica de inmunoelectrotransferencia (Western blot) con un suero hiperinmune obtenido frente a antígenos de excreción/secreción de adultos de F. hepatica, se pudo demostrar que en las heces de los pacientes se encuentran antígenos de posible interés para el diagnóstico con masas moleculares de 14, 19, 20, 23, 25, 32, 46, 51 y 62 kilodaltons (kDa). Además, se comprobó que algunos de estos péptidos (los de 14, 20, 23 y 51 kDa) son reconocidos también por la mayoría de los sueros de pacientes crónicos. Después de purificar por cromatografía de afinidad los antígenos presentes en heces de ratas con 6 a 12 semanas de infección, empleando para ello el anticuerpo monoclonal ES78 acoplado a Sepharosa 4B-CNBr, se identificaron seis polipéptidos de 11, 14, 26, 32, 47 y 51 kDa; otros tres polipéptidos, de 17, 24 y 66 kDa, solo se pudieron identificar en heces de ratas con 10 a 12 semanas de infección. Nuestros resultados sugieren que estos polipéptidos pueden ser antígenos comunes a ambos estadios parasitarios y constituir importantes marcadores de la fascioliasis aguda y crónica, en particular los de 14, 24, 26 y 51 kDa, puesto que reaccionaron con el inmunosuero, los sueros humanos y el anticuerpo monoclonal ES78.

This paper was aimed at identifying the main components present in the excretory-secretory antigens of adult parasite which are recognized by the sera of rats experimentally infected with metacercariae of Fasciola hepatica, by using the Western Blot technique. The cynetics of antibodies was also determined with and indirect ELISA. The results obtained allowed to find 31 components with approximate mollecular weights from 11 to 136 kD. The predominant fractions were the following: 11-13 kD, 14-16 kD, 23-33 kD, 55-57 kD, 65-71 kD, and 86-136 kD. Antibodies were detected from the 2nd. week of infection in 80 % of the animals and from the 3rd. week in 100 % of them. There were no antibodies during the first week. The identification of these antibodies may contribute to a better understanding of the mechanisms of immunity linked with the infection by F. hepatica.

El objetivo de este estudio fue realizar la identificación de los principales componentes presentes en los antígenos de excreción-secreción de parásitos adultos que son reconocidos por los sueros de ratas infectadas experimentalmente con metacercarias de Fasciola hepatica, mediante la técnica de Western Blot. Además, se determinó la cinética de anticuerpos con un ELISA indirecto. Los resultados obtenidos permitieron identificar 31 componentes con pesos moleculares aproximados de 11 a 136 kD, donde las fracciones predominantes fueron: 11-13 kD, 14-16 kD, 23-33 kD, 55-57 kD, 65-71 kD y 86-136 kD. Se detectaron anticuerpos a partir de la 2da. semana de infección en el 80 % de los animales y en la 3ra. semana en el 100 % de ellos, no se detectaron en la 1ra. semana de la infección. La identificación de estos antígenos podría contribuir a una mejor comprensión de los mecanismos de la inmunidad vinculados a la infección por F.hepatica.