Biological effects of Lippia alba essential oil against Anopheles gambiae and Aedes aegypti.

The management of mosquito resistance to chemical insecticides and the biting behaviour of some species are motivating the search for complementary and/or alternative control methods. The use of plants is increasingly considered as a sustainable biological solution for vector control. The aim of this study was to evaluate the biological effects of the essential oil (EO) of Lippia alba harvested in Abidjan (Côte d'Ivoire) against Anopheles gambiae and Aedes aegypti mosquitoes. Phytochemical compounds were identified by GC-MS. Knockdown and mortality were determined according to the WHO test tube protocol. Contact irritancy was assessed by observing the movement of mosquitoes from a treated WHO tube to a second untreated tube. Non-contact repellency was assessed using a standardised high-throughput screening system (HITSS). Blood meal inhibition was assessed using a membrane feeding assay treated with EO. The EO was identified as the citral chemotype. The EO gave 100% KD60 in both species at a concentration of 1%. Mortalities of 100% were recorded with An. gambiae and Ae. aegypti at concentrations of 1% and 5% respectively. The highest proportions of females escaping during the contact irritancy test were 100% for An. gambiae at 1% concentration and 94% for Ae. aegypti at 2.5% concentration. The 1% concentration produced the highest proportions of repelled mosquitoes in the non-contact repellency tests: 76.8% (An. gambiae) and 68.5% (Ae. aegypti). The blood meal inhibition rate at a dose of 10% was 98.4% in Ae. aegypti but only 15.5% in An. gambiae. The citral chemotype of L. alba EO has promising biological effects in both species that make it a potentially good candidate for its use in mosquito control. The results obtained in this study encourage the further evaluation of L. alba EOs from other localities and of different chemotypes, under laboratory and field conditions.

The Use of Chemoprophylaxis after Floods to Reduce the Occurrence and Impact of Leptospirosis Outbreaks.

Record-breaking and devastating rainfall events have occurred in the past decade. Rain and floods are considered the main risk factors for leptospirosis and several outbreaks have been reported following extreme weather events. In such situations, one possible intervention to prevent leptospirosis cases in high-risk groups is the use of chemoprophylaxis. However, not enough evidence of its effect is available. The objectives of this study were to review the literature on the current practices of chemoprophylaxis for leptospirosis and to explore, using a mathematical model, how various chemoprophylaxis scenarios may affect the progression of a leptospirosis outbreak. Twenty-six peer-reviewed publications were selected (10 quantitative studies, two systematic reviews and 14 articles of other types). Oral doxycycline was the most used antibiotic for chemoprophylaxis of leptospirosis. Post-exposure prophylaxis was assessed in four studies following a natural disaster. Although evidence of the effectiveness of post-exposure prophylaxis is inconsistent, the direction of association supported a protective effect for morbidity and mortality. The theoretical model showed how the assumed benefit of chemoprophylaxis was influenced by the time and rate of administration. Future models should consider the heterogeneity of affected communities, improved estimates of the effect of chemoprophylaxis on leptospirosis infection and disease, as well as potential detrimental impacts. Additional research is critical to provide clear evidence-based recommendations for leptospirosis control during an outbreak. The results of this study suggest that chemoprophylaxis may provide some protection in reducing the number of leptospirosis cases after a high-risk exposure; however, the effective benefit may depend on a variety of factors such as the timing and coverage of prophylaxis. The information summarized can be used to support decision-making during a high-risk event.

Esterilización tubaria transvaginal: Experiencia en el Hospital Universitario de Caracas

Objetivo: Evaluar las ventajas de la técnica de esterilización tubaria por vía vaginal en pacientes que acudieron al servicio de Ginecología del Hospital Universitario de Caracas y Ambulatorio del IVSS Patrocino Peñuela Ruíz, de enero a noviembre de 2014. Métodos: Investigación tipo ensayo clínico multicéntrico, en 49 mujeres no puérperas en edad fértil que solicitaron la esterilización quirúrgica. Se realizó la técnica de colpotomía posterior para localizar las trompas y realizar la esterilización. Resultados: La edad promedio fue de 32,5 años. El 80 % tenía de 1 a 3 partos. El 12,2 % tenía una cesárea previa y dos el 16, 3 %. El tiempo promedio de intervención fue de 22,8 minutos y de pérdida sanguínea de 32,5 cm³, sin necesidad de hemoderivados. Las complicaciones intraoperatorias se presentaron en 6 % de los casos, ameritando laparotomía 2 casos. Se pudo demostrar que las adherencias retrasan el tiempo quirúrgico. Según la escala visual análoga (EVA), 53,1 % de las pacientes a las seis horas no tenía dolor y a las 12 horas había disminuido notoriamente en el 85,7 %. Conclusión: La esterilización quirúrgica por colpotomía es beneficiosa porque el tiempo quirúrgico es corto, el sangrado escaso, el dolor leve y las complicaciones bajas.

Objective: To evaluate the advantages of tubal ligation by colpotomy incision in patients who assisted to the Gynecology Unit of University Hospital of Caracas and Patrocino Peñuela Ruíz Hospital form January to November 2014. Methods: Multicentric clinical assay, performed in 49 patients of reproductive age who demanded tubal ligation. Posterior colpotomy was performed to access the Fallopian tubes. Results: Mean age was 32,5 years. Eighty percent had 1 to 3 vaginal deliveries. One previous C section was reported in 12 %, and 2 in 16, 3 %. Mean surgery time was 22,8 minutes, and the mean blood loss 32,5 cc; blood transfusión was not required. Intraoperatory complications were present in 6 % of cases, 2 of them required laparotomy. The presence of adherences was related to longer surgical time. According to the Visual Analogue Scale (VAS), 53,1 % of the patients had no pain 6 hours after the surgery, and pain decreased significantly in 85. 7 % of the patients 12 hours after the procedure. Conclusion: Tubal ligation by colpotomy is highly recommended due to the short surgical time and low rate of complications, blood loss and pain.

'Do you remember the first time?' Host plant preference in a moth is modulated by experiences during larval feeding and adult mating.

In insects, like in other animals, experience-based modulation of preference, a form of phenotypic plasticity, is common in heterogeneous environments. However, the role of multiple fitness-relevant experiences on insect preference remains largely unexplored. For the multivoltine polyphagous moth Spodoptera littoralis we investigated effects of larval and adult experiences on subsequent reproductive behaviours. We demonstrate, for the first time in male and female insects, that mating experience on a plant modulates plant preference in subsequent reproductive behaviours, whereas exposure to the plant alone or plant together with sex pheromone does not affect this preference. When including larval feeding experiences, we found that both larval rearing and adult mating experiences modulate host plant preference. These findings represent the first evidence that host plant preferences in polyphagous insects are determined by a combination of innate preferences modulated by sensory feedback triggered by multiple rewarding experiences throughout their lifetime.

Oral surgery in patients under antithrombotic therapy / Cirugía bucal en pacientes con terapia antitrombótica: revisión narrativa

Population aging and the increasing rates of cardiovascular diseases have raised the number of patients receiving antithrombotic therapy in elective or emergency dental care, including surgical procedures. The aim of this article is to review the evidence and clinical guidelines for management of patients on antithrombotic therapy published in the past five years. TheAmerican Antithrombotic Therapy Guideline - 2012 - generally recommends not to suspend antiplatelet or anticoagulant treatment in dental procedures since they are considered to have low bleeding risk and easy resolution. In the dental field, there is ample published evidence regarding oral surgical procedure management, especially by maxillofacial surgeons, showing a low number of complications associated with extractions or other minor oral surgical procedures without suspending antithrombotic drugs and only taking some minimum safeguards, such as healing by first intention or the use of some local hemostatic agents. In general, patients under chronic antithrombotic therapy should keep their medication when undergoing low and medium complexity dental procedures, since complications are minor and easy to handle. Due to interactions between them, particular care should be taken with patients using more than one drug...

El envejecimiento poblacional y el aumento patologías cardiovasculares ha aumentado la cantidad de pacientes bajo terapia antitrombótica que reciben atención dental electiva o de urgencia, incluidos los procedimientos quirúrgico. El objetivo de este artículo es revisar la evidencia y las guías clínicas publicadas en los últimos 5 anos respecto al manejo odontológico de pacientesbajo terapia antitrombótica. La guía clínica americana de terapia antitrombótica del ano 2012 recomienda en general no suspender la terapia antiplaquetaria ni anticoagulante, en los procedimientos dentales ya que son considerados como de bajo riesgo de sangrado y de fácil resolución. En el área odontológica existe amplia evidencia publicada respecto al manejo de procedimientos quirúrgicos bucales, especialmente por cirujanos maxilofaciales, que ha demostrado la baja cantidad de complicaciones asociadas a exodoncias u otras cirugías menores de la cavidad bucal; sin la necesidad de suspender los medicamentos antitrombóticos y tomando algunos resguardos mínimos como la cicatrización por primera intención o el uso de algunos agentes hemostáticos locales. En términos generales los pacientes bajo terapia antitrombótica crónica deben mantener sus medicamentos cuando son sometidos a procedimientos dentales de baja y mediana complejidad, ya que las complicaciones son menores y de sencillo manejo. Se debe poner especialatención en pacientes con más de un medicamento, por las interacciones entre ellos...

Insect host plant selection in complex environments.

Selection of suitable host plants is essential for the development and survival of herbivorous insects. Here we address behavioural mechanisms and the role of olfactory cues governing host choice, and their adaptive significance in complicated ecological contexts, with a focus on polyphagous insects. We also consider how recent developments in the study of olfactory systems of insects can provide a functional description of physiological mechanisms behind host plant choice. This may apply from the broader evolutionary history and local adaptations of olfactory receptor genes, to the underlying neural mechanisms behind innate host preferences and experience-based plasticity in host plant choice.