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1.
Environ Sci Pollut Res Int ; 27(24): 29867-29899, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32500500

RESUMO

We present a synthetic review and expert consultation that assesses the actual risks posed by arthropod pests in four major crops, identifies targets for integrated pest management (IPM) in terms of cultivated land needing pest control and gauges the implementation "readiness" of non-chemical alternatives. Our assessment focuses on the world's primary target pests for neonicotinoid-based management: western corn rootworm (WCR, Diabrotica virgifera virgifera) in maize; wireworms (Agriotes spp.) in maize and winter wheat; bird cherry-oat aphid (Rhopalosiphum padi) in winter wheat; brown planthopper (BPH, Nilaparvata lugens) in rice; cotton aphid (Aphis gossypii) and silver-leaf whitefly (SLW, Bemisia tabaci) in cotton. First, we queried scientific literature databases and consulted experts from different countries in Europe, North America, and Asia about available IPM tools for each crop-pest system. Next, using an online survey, we quantitatively assessed the economic relevance of target pests by compiling country-level records of crop damage, yield impacts, extent of insecticide usage, and "readiness" status of various pest management alternatives (i.e., research, plot-scale validation, grower-uptake). Biological control received considerable scientific attention, while agronomic strategies (e.g., crop rotation), insurance schemes, decision support systems (DSS), and innovative pesticide application modes were listed as key alternatives. Our study identifies opportunities to advance applied research, IPM technology validation, and grower education to halt or drastically reduce our over-reliance on systemic insecticides globally.


Assuntos
Inseticidas , Praguicidas , Animais , Ásia , Europa (Continente) , Neonicotinoides , América do Norte
2.
Expert Rev Pharmacoecon Outcomes Res ; 13(3): 293-311, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23763528

RESUMO

Community services comprise an important part of a country's HIV response. English language cost and cost-effectiveness studies of HIV community services published between 1986 and 2011 were reviewed but only 74 suitable studies were identified, 66% of which were performed in five countries. Mean study scores by continent varied from 42 to 69% of the maximum score, reflecting variation in topics covered and the quality of coverage: 38% of studies covered key and 11% other vulnerable populations - a country's response is most effective and efficient if these populations are identified given they are key to a successful response. Unit costs were estimated using different costing methods and outcomes. Community services will need to routinely collect and analyze information on their use, cost, outcome and impact using standardized costing methods and outcomes. Cost estimates need to be disaggregated into relevant cost items and stratified by severity and existing comorbidities. Expenditure tracking and costing of services are complementary aspects of the health sector 'resource cycle' that feed into a country's investment framework and the development and implementation of national strategic plans.


Assuntos
Serviços de Saúde Comunitária/organização & administração , Infecções por HIV/terapia , Avaliação de Resultados em Cuidados de Saúde/métodos , Serviços de Saúde Comunitária/economia , Análise Custo-Benefício , Custos e Análise de Custo , Infecções por HIV/economia , Infecções por HIV/fisiopatologia , Humanos , Índice de Gravidade de Doença
3.
Appl Environ Microbiol ; 72(2): 1595-603, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16461715

RESUMO

The effect of Cry proteins of Bacillus thuringiensis on the green lacewing (Chrysoperla carnea) was studied by using a holistic approach which consisted of independent, complementary experimental strategies. Tritrophic experiments were performed, in which lacewing larvae were fed Helicoverpa armigera larvae reared on Cry1Ac, Cry1Ab, or Cry2Ab toxins. In complementary experiments, a predetermined amount of purified Cry1Ac was directly fed to lacewing larvae. In both experiments no effects on prey utilization or fitness parameters were found. Since binding to the midgut is an indispensable step for toxicity of Cry proteins to known target insects, we hypothesized that specific binding of the Cry1A proteins should be found if the proteins were toxic to the green lacewing. In control experiments, Cry1Ac was detected bound to the midgut epithelium of intoxicated H. armigera larvae, and cell damage was observed. However, no binding or histopathological effects of the toxin were found in tissue sections of lacewing larvae. Similarly, Cry1Ab or Cry1Ac bound in a specific manner to brush border membrane vesicles from Spodoptera exigua but not to similar fractions from green lacewing larvae. The in vivo and in vitro binding results strongly suggest that the lacewing larval midgut lacks specific receptors for Cry1Ab or Cry1Ac. These results agree with those obtained in bioassays, and we concluded that the Cry toxins tested, even at concentrations higher than those expected in real-life situations, do not have a detrimental effect on the green lacewing when they are ingested either directly or through the prey.


Assuntos
Proteínas de Bactérias/toxicidade , Toxinas Bacterianas/toxicidade , Endotoxinas/toxicidade , Insetos/efeitos dos fármacos , Controle Biológico de Vetores , Animais , Bacillus thuringiensis , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias/administração & dosagem , Proteínas de Bactérias/metabolismo , Toxinas Bacterianas/administração & dosagem , Toxinas Bacterianas/metabolismo , Sistema Digestório/efeitos dos fármacos , Sistema Digestório/metabolismo , Endotoxinas/administração & dosagem , Endotoxinas/metabolismo , Proteínas Hemolisinas , Insetos/fisiologia , Microvilosidades/efeitos dos fármacos , Microvilosidades/metabolismo
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