Oogenic development and gonotrophic cycle of Aedes aegypti and Aedes albopictus in laboratory / Desarrollo oogénico y ciclo gonotrófico de Aedes aegypti y Aedes albopictus en laboratorio

Abstract: Objective: To determine the time of oogenic development and the length of the gonotrophic cycle of Ae. aegypti and Ae. albopictus in laboratory. Materials and methods: Bloodfed females of Ae. aegypti and Ae. albopictus were dissected every 4 h to determine the development status of the follicles according to the Christophers' stages. Results: The minimum time of oocyte maturation in Ae. aegypti and Ae. albopictus was 64-82 h and 52-64 h post-feeding, respectively. We found that the gonotrophic cycle of Ae. aegypti (3.7-4.2 d) is longer than that of Ae. albopictus (3.2-3.7 d). The follicle length showed significant differences between species at Christophers' stages 2" and 5, whereas follicle amplitude was different between the two mosquitoes at stages 2", 3 and 4. Conclusions: The study provided new evidence on the reproductive strategies of Ae. aegypti and Ae. albopictus females that coexist in the Neotropical region of Mexico.

Resumen: Objetivo: Determinar el tiempo de desarrollo oogénico y del ciclo gonotrófico de Aedes aegypti y Aedes albopictus en laboratorio. Material y métodos: Hembras de Ae. aegypti y Ae. albopictus alimentadas con sangre fueron disecadas cada cuatro horas para determinar el estado de desarrollo folicular, según los estadios de Christophers. Resultados: El tiempo mínimo de maduración del oocito en Ae. aegypti y Ae. albopictus fue de 64-82 h y 52-64 h post-alimentación, respectivamente. El ciclo gonotrófico de Ae. aegypti (3.7-4.2 d) fue mayor que el de Ae. albopictus (3.2-3.7 d). La longitud folicular presentó diferencias significativas entre las especies en los estadios de Christophers 2" y 5, mientras que la amplitud folicular fue diferente entre ambos mosquitos en los estadios 2", 3 y 4. Conclusiones: El estudio proporcionó nueva evidencia sobre la estrategia reproductiva de las hembras de Ae. aegypti y Ae. albopictus que coexisten en la región neotropical de México.

recuencia y características demográficas de pacientes con diagnóstico de trombosis de stents coronarios implantados en un hospital universitario entre enero de 2011 a diciembre de 2012 / Frequency and demographic characteristics of patients diagnosed thrombosis coronary stent implantation in a university hospital from January 2011 to December 2012

Objetivo: Establecer la frecuencia y las características demográficas de pacientes con diagnóstico de trombosis de stent coronario atendidos en el Hospital Universitario Clínica San Rafael, de Bogotá, durante un periodo de 24 meses. Métodos: Estudio descriptivo retrospectivo en el que se revisaron las historias clínicas de pacientes mayores de 18 años con diagnóstico de trombosis de stent coronario confirmado mediante arteriografías realizadas en dicha institución en un lapso de 24 meses, atendidos de forma ambulatoria, en los departamentos de urgencias y/o hospitalización. Resultados Se realizaron 890 arteriografías con angioplastia e implante de stent, en las que se encontró un 2,7% de frecuencia de trombosis del stent; en el 70% los hombres presentaron un promedio de edad menor respecto a las mujeres (63,0 vs. 70,3 años). Las comorbilidades más frecuentes fueron: hipertensión arterial en el 65%, diabetes mellitus en el 25% y enfermedad renal crónica en el 10% de los casos. El promedio de fracción de eyección del ventrículo izquierdo fue del 38,7%. Incidentalmente, durante el análisis de datos se encontró fenómeno de reestenosis del stent en el 14,5% (n = 36) entre quienes se les hizo angioplastia más implante de stent. Conclusiones: La frecuencia de trombosis del stent coronario en la población analizada es similar a la reportada en la literatura mundial. Es más común en el sexo masculino, a una edad de aparición más temprana asociada con un deterioro marcado de la función ventricular izquierda. La alta frecuencia de evento de reestenosis del stent requiere más estudios en el futuro.

Objective: Establish frequency and demographic characteristics of patients with diagnosis of coronary stent thrombosis into Hospital Universitario Clínica San Rafael (HUCSR) over a time period of 24 months. Methods: Retrospective and descriptive Study. Clinical records were reviewed for patients older 18 with diagnosis of coronary stent thrombosis, confirmed through coronary arteriography made in HUCSR-Hemodinamics department on urgency, inpatient or outpatient, on a 24-month time period. Results: 890 arteriography and angioplasty plus stent implantation were performed. Frequency of coronary stent thrombosis was of 2.7%, in 70% of the cases male patients were younger on average than women (63.0 years old vs 70.3 years old). Most commonly described associated diseases were arterial hypertension (65%), diabetes mellitus (25%), and chronic kidney disease (10%). The average left ventricular ejection fraction was 38.7%. Incidentally, while data were being recollected, the stent stenosis was found in too many patients, with a frequency of 14.5% (n = 36) on patients who underwent angioplasty and stent implantation. Conclusions: Coronary stent thrombosis frequency is similar to reports around the world. This complication is more frequent in male patients, onset age was younger and associated with worse left ventricular function. High coronary stent stenosis frequency required more studies.

Color preference of Anastrepha obliqua (Diptera, Tephritidae) / Preferência de cor por Anastrepha obliqua (Macquart) (Diptera, Tephritidae)

The color preference of A. obliqua was evaluated in two-choice tests. The results showed that both sexes were attracted to wavelengths ranging from 340 nm to 670 nm, although the broad major peak of attraction occurred between 380 and 570 nm.

A preferência de cor por A. obliqua foi avaliada em testes de dupla escolha. Os resultados mostraram que ambos os sexos foram atraídos aos comprimentos de onda que variam de 340 nm a de 670 nm, embora o principal pico da atração de A. obliqua tenha ocorrido entre 380 e 570 nm.

Ecological control of Triatoma dimidiata (Latreille, 1811): five years after a Costa Rican pilot project

An ecological pilot project for the control of Triatoma dimidiata allowed a new evaluation four and five years after environmental modifications in the peridomestic areas of 20 households. It was verified that the two groups of houses, 10 case-houses and 10 control-houses, were free of insects after those periods of time. In the first group, the owners started a chicken coop in the backyard and a colony of bugs was found there without infesting the house. In the second group, the inhabitants of one house once again facilitated the conditions for the bugs to thrive in the same store room, reaffirming that man-made ecotopes facilitates colonization. This ecological control method was revealed to be reliable and sustainable and it is recommended to be applied to those situations where the vectors of Chagas disease can colonize houses and are frequent in wild ecotopes.

Behavioral and olfactory antennal responses of Solenopsis geminata (Fabricius) (Hymenoptera: Formicidae) workers to their dufour gland secretion

Behavioral and electrophysiological tests were performed to evaluate the responses of workers of the ant Solenopsis geminata (Fabricius) from different size categories to Dufour gland extracts. Morphometric measures based in head widths across eyes were used to determine worker sizes. Trail following response of different worker sizes to Dufour gland extract from workers of different sizes was assessed. For each worker size category olfactory responses to Dufour gland extracts were determined using electroantennography (EAG). Gas chromatography and mass spectrometry (GC-MS) were used to determine the chromatographic profile of Dufour gland secretion for each worker size. Morphometric measures permitted to classify the workers of S. geminata as large, medium and small workers. Medium S. geminata workers displayed a significantly higher behavioral response to Dufour gland extracts produced by medium size workers. Similarly, medium workers showed a significantly higher EAG response to Dufour gland extracts produced by medium sized workers. Chromatographic profile of Dufour gland secretions produced by workers showed that each size category exhibited a characteristic profile of the three main components considered as potential trail pheromone constituents. This work showed that medium workers of S. geminata exhibited a high trail-following behavior as well as a high antennal response to Dufour gland secretion. This and their relative abundance in field foraging areas, suggest that medium-sized workers are specialized in foraging activities.

Se efectuaron pruebas comportamentales y electrofisiológicas para evaluar las respuestas de obreras de Solenopsis geminata (Fabricius) de diferentes tamaños a extractos de la glándula de Dufour. Se usaron medidas del ancho de la cabeza para determinar el tamaño de las obreras. Se evualuó la respuesta de seguimiento de ruta de obreras de diferentes tamaños a extractos de la glándula de Dufour proveniente de obreras de diferentes tamaños. Para cada grupo de obrera de determinado tamaño se le determinó la respuesta olfatoria por medio de electroantenografía (EAG). Se utilizó Cromatografía de Gases acoplada a Espectrometría de Masas (GC-EM) para determinar el perfil cromatográfico de la secreción de la glándula de Dufour para cada grupo de obreras. Las medidas morfométricas permitieron clasificar a las obreras de acuerdo a su tamaño en grandes, medianas y pequeñas. Las obreras medianas de S. geminata exhibieron una respuesta comportamental alta a los extractos glandulares de hormigas medianas. Las obreras medianas mostraron también una alta respuesta antenal a los extractos de obreras medianas. El perfil cromatográfico de la secreción de la glándula de Dufour producida por obreras muestra que cada tamaño exhibió un perfil característico de los tres componentes potenciales como feromona de ruta. Concluimos que las obreras de tamaño mediano exhibieron altas respuestas tanto comportamentales como olfatorias a la secreción de la glándula de Dufour. Lo anterior y el hecho de que sean las más abundantes en el área de forrajeo sugieren que este grupo de obreras está especializado en actividades de forrajeo.

Environmental management for the control of Triatoma dimidiata (Latreille, 1811), (Hemiptera: Reduviidae) in Costa Rica: a pilot project

An ecological control method, using environmental management operations, based on biological and behavioral characteristics of Triatoma dimidiata (Latreille, 1811), was implemented as a pilot project in an area of Costa Rica where the bug is prevalent. The sample was represented by 20 houses with peridomestic colonies (two also had indoor infestation), divided in two equivalent groups of 10 each. In one group we intervened the houses, i.e. all objects or materials that were serving as artificial ecotopes for the bugs were removed, and the second group was used as control houses. After a year of periodic follow up, it became evident that in those houses with a modified environment the number of insects had decreased notoriously even after the first visits and this was more evident after a period of 12.5 to 13.5 months in which no insects were detected in eight of the houses. It also became clear that in this group of houses, recolonization by wild bugs from the surrounding areas, became more difficult, probably due to the absence of protection from bug predators. In the control houses, with the exception of three in which the inhabitants decided to intervene on their own, and another house with a peculiar situation, the insect populations remained the same or even showed a tendency to increase, as confirmed at the end of the experiment. We believe that the method is feasible, low costing and non contaminating. It could be used successfully in other places where T. dimidiata is common and also in countries where other species colonize peridomestic areas of homes. Environmental management of this kind should seek the participation of the members of the communities, in order to make it a more permanent control measure.

Life cycle and influence of age and feeding on the first mating of Triatoma mazzottii (Hemiptera: Reduviidae)

A cohort of 100 eggs of Triatoma mazzottii Usinger was studied to obtain information on its life cycle. Egg incubation took 24 days; mean duration of 1st, 2nd, 3rd, 4th, and 5th instar nymphs was 27, 36, 39, 46 and 64 days respectively; mean time from egg to adult was 236 days. The total duration of the nymphal stages was 212 days. The total nymph mortality in cohort was 16.3% and the embryonic egg mortality was 14.0%. The grater mortality occured in the 2nd instar. The average number of eggs/female/week was 9.8 during 15 weeks of observation. Of the total eggs laid (2,514), only 58.7% hatched. The total of insects that achieved the adult stage (72), 38 were females (52.8%), and 34 were males (47.2%). The influence of age and feeding on the first mating of T. mazzottii were also studied. It was found that the first mating depended on the male's age and it was on the average 30 days after the last imaginal molt. The female could be mating since 2nd days after the imaginal life. The nutritional status did not play an important role in the capacity of the insect for the first mating