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[en] The rapid spread of highly aggressive arboviruses, parasites, and bacteria along with the development of resistance in the pathogens and parasites, as well as in their arthropod vectors, represents a huge challenge in modern parasitology and tropical medicine. Eco-friendly vector control programs are crucial to fight, besides malaria, the spread of dengue, West Nile, chikungunya, and Zika virus, as well as other arboviruses such as St. Louis encephalitis and Japanese encephalitis. However, research efforts on the control of mosquito vectors are experiencing a serious lack of eco-friendly and highly effective pesticides, as well as the limited success of most biocontrol tools currently applied. Most importantly, a cooperative interface between the two disciplines is still lacking. To face this challenge, we have reviewed a wide number of promising results in the field of green-fabricated pesticides tested against mosquito vectors, outlining several examples of synergy with classic biological control tools. The non-target effects of green-fabricated nanopesticides, including acute toxicity, genotoxicity, and impact on behavioral traits of mosquito predators, have been critically discussed. In the final section, we have identified several key challenges at the interface between "green" nanotechnology and classic biological control, which deserve further research attention.
[en] To assess the abnormalities of haemotological parameters associates to different types of malaria. Design: Observational study. Study Setting and Duration: Present study was carried out in the medicine department, of (LUH) Liaquat University Objective: To assess the abnormalities of haemotological parameters associates to different types of malaria. Design: Observational study. Study Setting and Duration: Present study was carried out in the medicine department, of (LUH) University of Medical and Health Sciences Hospital Hyderabad / Jamshoro from March 2013 to august 2013. Method: All the cases after diagnosis having, tuberculosis, hepatitis, typhoid, dengue fever, pregnancy and diagnosis of meningitis excluded from the present study. Blood sample of the patients for CBC were sent to the diagnostic and research laboratory of liaquat medical University Hospital Hyderabad. After reports all the hematological abnormalities was documented. Results: Total 200 patients were selected in this study, and mean age was found as; Mean +- SD 32.4 +- 5.6. Female were found in the majority 58%. Vivax was found most common in the cases with percentage of 68%. According to the haematological abnormalities, in the vivax infected patients abnormal Hb (g/dl) was found in (24.2%) cases and thrombocytopenia was found with the (20.4%) cases in the cases, while Falciparum infected patients mostly abnormal H,b (g/dl) was found in 27 (20.4%) and thrombocytopenia found most common 31 (45.5%) respectively. Conclusion: In the conclusion of this study, there are a big haematological disturbance are evaluated in the malarial affected patients, mostly thrombocytopenia and anemia. (author)
[en] In 2014, as an attempt to address the Zika health crisis by controlling the mosquito population, Brazil took the unprecedented action of applying a chemical larvicide, pyriproxyfen, to drinking water sources. The World Health Organization has established an acceptable daily intake of pyriproxyfen to be 100 μg per kg of body weight per day, but studies have demonstrated that at elevated doses (>5000 mg/kg), there are adverse effects in mice, rats and dogs. To better understand the potential developmental toxicity of pyriproxyfen, we utilized the embryonic zebrafish. Our results demonstrate that the concentration resulting in 50% of animals presenting adverse morphological effects (EC50), including craniofacial defects, was 5.2 μM for daily renewal exposure, and above this concentration, adverse behavioral effects were also observed in animals that followed a static exposure regimen. Thus, zebrafish data suggest that the developmental toxicity of pyriproxyfen may not be limited to insects. - Highlights: • Rapid 5-day zebrafish assay detected developmental and behavioral effects of pyriproxyfen. • 50% adverse effect (EC50) was 5.2 μM for daily renewal exposure. • Behavioral effects observed at concentrations higher than 6.4 μM. - In the zebrafish model, daily renewal of 5.2 μM pyriproxyfen resulted in 50% of the test subjects showing morphological defects and similar pyriproxyfen exposures resulted in adverse behavioral effects.
[en] Aedes albopictus (Skuse), the Asian Tiger Mosquito, has invaded several countries, during the last years, mainly due to the passive transportation in used tires. In Europe the species firstly arrived in Albany in 1979, then in Italy in 1990, in France in 1999 (Schaffner and Karch 1999), in Belgium in 2000, in Montenegro in 2001. Other countries have already been colonised or are under colonisation in Africa and the Americas. In Italy the colonisation process appears to be very quick mainly due to the passive transportation of adults inside vehicles, to be currently found in seven regions. In its original distribution, Ae. albopictus is known to be a very important vector of many arboviruses including yellow fever and dengue. Moreover it is also capable of transmitting indigenous arboviruses in newly colonised areas, as well as filariasis (Dirofilaria immitis Leidy and D. repens Railleiet and Henry) and other arboviruses like Sindbis, Chikungunya, West Nile and Rift Valley. Finally this species can also cause severe annoyance because of its anthropophily and painful bite. The species is mainly exploiting man-made containers showing an urban and periurban distribution. This 'island' distribution and the low active dispersal capability make it possible considering as convenient the application of SIT as a component of the IPM programmes already implemented. In 1999 we therefore started a project financed with local funds in order to investigate the feasibility of SIT application against Ae. albopictus in Italy
[en] An acceptable live-attenuated dengue virus vaccine candidate should have low potential for transmission by mosquitoes. We have identified and characterized a mutation in dengue virus type 4 (DEN4) that decreases the ability of the virus to infect mosquitoes. A panel of 1248 mutagenized virus clones generated previously by chemical mutagenesis was screened for decreased replication in mosquito C6/36 cells but efficient replication in simian Vero cells. One virus met these criteria and contained a single coding mutation: a C-to-U mutation at nucleotide 7129 resulting in a Pro-to-Leu change in amino acid 101 of the nonstructural 4B gene (NS4B P101L). This mutation results in decreased replication in C6/36 cells relative to wild-type DEN4, decreased infectivity for mosquitoes, enhanced replication in Vero and human HuH-7 cells, and enhanced replication in SCID mice implanted with HuH-7 cells (SCID-HuH-7 mice). A recombinant DEN4 virus (rDEN4) bearing this mutation exhibited the same set of phenotypes. Addition of the NS4B P101L mutation to rDEN4 bearing a 30 nucleotide deletion (Δ30) decreased the ability of the double-mutant virus to infect mosquitoes but increased its ability to replicate in SCID-HuH-7 mice. Although the NS4B P101L mutation decreases infectivity of DEN4 for mosquitoes, its ability to enhance replication in SCID-HuH-7 mice suggests that it might not be advantageous to include this specific mutation in an rDEN4 vaccine. The opposing effects of the NS4B P101L mutation in mosquito and vertebrate systems suggest that the NS4B protein is involved in maintaining the balance between efficient replication in the mosquito vector and the human host
[en] Gene transformation for the control of mosquito transmitted diseases is currently limited by the lack of an efficient method for the transfection and integration of exogenous DNA. The biolistic technique, which uses high velocity DNA coated microprojectiles, has been developed to introduce DNA into embryos of Anopheles gambiae. The biolistic parameters have been characterized and optimized on the basis of transient expression of the luciferase reporter gene placed under the control of the heat shock protein 70 promoter of Drosophila. High luciferase activities were observed for biolistic DNA introduction performed in the early embryonic stages. Because of the very large number of embryos which can easily be transfected biolistically, and because DNA is probably delivered directly into the nuclei, the biolistic method could be useful for obtaining insect genetic transformation, despite the low frequency of exogenous DNA integration. Moreover, this technique has already been proved suitable for embryo transfection in other invertebrates, such as crustaceans. (author). 8 refs
[en] Full text: stably inherited through successive generations. Progress in the transformation of non-drosophilid insect species, such as mosquitoes and true fruit flies, has resulted, in main part, from the identification and utilisation of new insect transposable elements. The hAT superfamily of transposable elements contains members from plants, fungi and animals and includes the active insect transposable elements hobo, Hermes and herves from Drosophila melanogaster, Musca domestica and Anopheles gambiae respectively. These three elements offer a unique system for study, since they are all active, yet show at some levels, significant sequence divergence. The central premise of our research is that the success with which transposable elements can be tamed and used as genetic tools in insects, particularly in field applications, is dependent on our knowledge of how they work in the nucleus. To this end we have undertaken a structure: function analysis of these three transposable elements as well as, in the case of herves, an analysis of its distribution in field populations of An. gambiae in regions of Africa. We will also discuss the possible roles that host factors may play in Hermes and herves element transposition and the implication that these might have for the use of transposable elements in genetic control programmes. Attempts at generating and testing hyperactive forms of the Hermes element transposase will also be discussed. (author)