Helicoverpa armigera: current status and future perspectives in Brazil.

The bollworm Helicoverpa armigera is a polyphagous pest first identified in the South American continent in Brazil during the 2012/13 crop season, worrying farmers across the country leading them to overuse insecticides in an attempt to control its outbreaks. However, it is essential to emphasize the importance of the adoption of Integrated Pest Management (IPM) philosophy, since improperly applied insecticides will exacerbate pest problem by eliminating the biological control agents and increase the production cost unnecessarily. Therefore, our work discusses, in more detail, the current status, recommended management, and future perspectives of this pest in Brazil. We conclude that, in spite of H. armigera infestation in Brazil, it will still be feasible for growers to adopt pestcontrol measures that have less impact on the environment in accordance with the standard principles of the IPM philosophy. Within this context, monitoring for pests and initiating control measures only when the pest populations reaches the economic thresholds (ET) recommended by research is crucial. These procedures protect crop sustainability, thus keeping growers competitive in the market while reducing costs and maximizing productivity. The arrival of H. armigera in Brazil has resulted in a national debate about the importance of IPM adoption. It is a chance to fully implement IPM in Brazil as it has never been done or seen before in the history of tropical agriculture. If IPM is successfully adopted in Brazil, the future perspective of H. armigera will be that of being a satisfactorily managed pest. In contrast, if only a simplified version of IPM is employed, H. armigera and many other pests will have a greater chance of surviving and causing severe damage to crops

Mortalidade do percevejo predador Podisus nigrispinus (Hemiptera, Pentatomidae) submetido a aplicações tópicas de fungicidas utilizados na cultura da soja.

Considerando a frequente utilização de fungicidas na cultura da soja para o controle da ferrugem-asiática (Phakopsora pachyrhizi) e a falta de informação sobre o impacto desses agroquímicos nos insetos predadores, estudou-se a influência de fungicidas utilizados na cultura da soja sobre a mortalidade do percevejo predador Podisus nigrispinus. O efeito de quatro fungicidas sobre percevejos adultos foi verificado por aplicação tópica de 2µl de cada produto diluído, nas doses recomendadas pelo fabricante em oncentrações equivalentes a um volume de aplicação de 200L de calda. ha -1 ,assim como concentrações 10 vezes superiores à recomendada. A aplicação foi realizada com microaplicador (Burkard Manufacturing Co. Ltd. Rickmansworth, Hertfordshire, England) em 20 insetos por tratamento em 3 repetições mais uma testemunha, posteriormente os insetos foram confinados em frascos de vidro tapados com filó. Lagartas da espécie Anticarsia gemmatalis serviam de alimento. Os insetos foram mantidos em BOD sob 25±1,5C° UR 70±5% e 12h de fotofase. Foram realizadas observações diárias durante 7 dias avaliando a mortalidade dos insetos. Os dados foram analisados pelo método de análise de variância, e as médias comparadas pelo teste de Tukey (P= 0,05). As aplicações com a dose recomendada do produto trifloxystrobina+ciproconazol (Sphere ® ) ocasionaram mortalidades médias de 48±1,6 e 50±2,8%, otetraconazol (Eminent 125EW®) provocou mortalidades de 45±5,7 e 71,5±6,6 %, nas doses recomendadas e 10 vezes maiores que a recomendada, respectivamente. Na testemunha observou-se uma mortalidade de 28±3,3% em média, mostrando diferença estatística em relação a esses produtos. Nos testes com os produtos metconazol (Caramba ®) e flutriafol+tiofanato-metílico (Celeiro®) observaram-se mortalidades de 41,5±3,3 e 30±2,8 % para a dose recomendada, e mortalidades de 35±2,8 e 40±2,8% nas doses 10 vezes maiores, respectivamente. Entretanto esses tratamentos não diferiram estatisticamente da testemunha

In vitro activities of amphotericin B, terbinafine, and azole drugs against clinical and environmental isolates of apergillus terreus Sensu Stricto

The antifungal susceptibilities of 40 clinical and environmental isolates of A. terreus sensu stricto to amphotericin B, terbinafine, itraconazole, and voriconazole were determined in accordance with CLSI document M38-A2. All isolates had itraconazole and voriconazole MICs lower than epidemiologic cutoff values, and 5% of the isolates had amphotericin B MICs higher than epidemiologic cutoff values. Terbinafine showed the lowest MICs. No significant differences were found when MICs of clinical and environmental isolates were compared.Fil: Fernández, Mariana Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Nordeste. Instituto de Medicina Regional; ArgentinaFil: Rojas, Florencia Dinorah. Universidad Nacional del Nordeste. Instituto de Medicina Regional; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Cattana, Maria Emilia. Universidad Nacional del Nordeste. Instituto de Medicina Regional; ArgentinaFil: Sosa, Maria de Los Angeles. Universidad Nacional del Nordeste. Instituto de Medicina Regional; Argentina. Universidad Nacional del Nordeste. Instituto de Medicina Regional; ArgentinaFil: Iovannitti, Cristina A.. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; ArgentinaFil: Lass Flörl, Cornelia. Medical University Of Innsbruck; AustriaFil: Giusiano, Gustavo Emilio. Universidad Nacional del Nordeste. Instituto de Medicina Regional; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Presenilin-1 regulates induction of hypoxia inducible factor-1α: altered activation by a mutation associated with familial Alzheimer's disease

<p>Abstract</p> <p>Background</p> <p>Mutations in presenilin-1 (<it>Psen1</it>) cause familial Alzheimer's disease (FAD). Both hypoxia and ischemia have been implicated in the pathological cascade that leads to amyloid deposition in AD. Here we investigated whether Psen1 might regulate hypoxic responses by modulating induction of the transcription factor hypoxia inducible factor 1-α (HIF-1α).</p> <p>Results</p> <p>In fibroblasts that lack Psen1 induction of HIF-1α was impaired in response to the hypoxia mimetic cobalt chloride, as well as was induction by insulin and calcium chelation. Reintroduction of human Psen1 using a lentiviral vector partially rescued the responsiveness of <it>Psen1-/- </it>fibroblasts to cobalt chloride induction. HIF-1α induction did not require Psen1's associated γ-secretase activity. In addition, the failure of insulin to induce HIF-1α was not explicable on the basis of failed activation of the phosphatidylinositol 3-kinase (PI3K/Akt) pathway which activated normally in <it>Psen1-/- </it>fibroblasts. Rather we found that basal levels of HIF-1α were lower in <it>Psen1-/- </it>fibroblasts and that the basis for lower constitutive levels of HIF-1α was best explained by accelerated HIF-1α degradation. We further found that Psen1 and HIF-1α physically interact suggesting that Psen1 may protect HIF-1α from degradation through the proteasome. In fibroblasts harboring the M146V Psen1 FAD mutation on a mouse Psen1 null background, metabolic induction of HIF-1α by insulin was impaired but not hypoxic induction by cobalt chloride. Unlike <it>Psen1-/- </it>fibroblasts, basal levels of HIF-1α were normal in FAD mutant fibroblasts but activation of the insulin-receptor pathway was impaired. Interestingly, in <it>Psen1-/- </it>primary neuronal cultures HIF-1α was induced normally in response to cobalt chloride but insulin induction of HIF-1α was impaired even though activation of the PI3K/Akt pathway by insulin proceeded normally in <it>Psen1-/- </it>neuronal cultures. Basal levels of HIF-1α were not significantly different in <it>Psen1-/- </it>neurons and HIF-1α levels were normal in <it>Psen1-/- </it>embryos.</p> <p>Conclusions</p> <p>Collectively these studies show that Psen1 regulates induction of HIF-1α although they indicate that cell type specific differences exist in the effect of Psen1 on induction. They also show that the M146V Psen1 FAD mutation impairs metabolic induction of HIF-1α, an observation that may have pathophysiological significance for AD.</p

Evaluation of Cytotoxicity and Genotoxicity of Acacia aroma Leaf Extracts

Acacia aroma, native plant from San Luis, Argentina, is commonly used as antiseptic and for healing of wounds. The present study was conducted to investigate the in vitro cytotoxicity and genotoxicity of hot aqueous extract (HAE) and ethanolic extract (EE) of A. aroma. The cytotoxic activity was assayed by neutral red uptake assay on Vero cell. Cell treatment with a range from 100 to 5000 g/mL of HAE and EE showed that 500 g/mL and 100 g/mL were the maximum noncytotoxic concentrations, respectively. The CC50 was 658 g/mL for EE and 1020 g/mL for HAE. The genotoxicity was tested by the single-cell gel electrophoresis comet assay. The results obtained in the evaluation of DNA cellular damage exposed to varied concentrations of the HAE showed no significant genotoxic effect at range of 1–20 mg/mL. The EE at 20 mg/mL showed moderate genotoxic effect related to the increase of the DNA percentage contained in tail of the comet; DNA was classified in category 2. At concentrations below 5 mg/mL, the results of cytotoxicity and genotoxicity of aqueous and ethanolic extracts of Acacia aroma guarantee the safety at cell and genomic level. However further studies are needed for longer periods including animal models to confirm the findings.Fil: Mattana, Claudia Maricel. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia; ArgentinaFil: Cangiano, Maria de Los Angeles. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Alcaraz, María Luciana. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Sosa, A.. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia; ArgentinaFil: Escobar, Franco Matias. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Sabini, C.. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales; ArgentinaFil: Sabini, Liliana Ines. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales; ArgentinaFil: Laciar, Analia Liliana. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia; Argentin

Life history of Megamelus scutellaris with description of immature stages (Hemiptera: Delphacidae)

The five immature stages of Megamelus scutellaris Berg (Hemiptera: Delphacidae) are described and illustrated. The main characters that distinguish the various stages are body size, number of tarsomeres and tibial spines, color, and number of teeth on the metatibial spur. New biological data based on laboratory rearing and field observations show that M. scutellaris can carry out its biological cycle successfully on water hyacinth, Eichhornia crassipes (Martius) Solms Laubach (Pontederiaceae). Mating occurs close to the water level and one to four eggs per scar are laid in apical portion of petiole and pseudolaminae. Ovipositional scars are recognized by three parallel marks. In addition, the efficient rearing in captivity, the high survivorship registered, and overwintering on only water hyacinth suggest M. scutellaris as a potential biocontrol agent of this invasive aquatic weed.Facultad de Ciencias Naturales y Muse

Life history of Megamelus scutellaris with description of immature stages (Hemiptera: Delphacidae)

The five immature stages of Megamelus scutellaris Berg (Hemiptera: Delphacidae) are described and illustrated. The main characters that distinguish the various stages are body size, number of tarsomeres and tibial spines, color, and number of teeth on the metatibial spur. New biological data based on laboratory rearing and field observations show that M. scutellaris can carry out its biological cycle successfully on water hyacinth, Eichhornia crassipes (Martius) Solms Laubach (Pontederiaceae). Mating occurs close to the water level and one to four eggs per scar are laid in apical portion of petiole and pseudolaminae. Ovipositional scars are recognized by three parallel marks. In addition, the efficient rearing in captivity, the high survivorship registered, and overwintering on only water hyacinth suggest M. scutellaris as a potential biocontrol agent of this invasive aquatic weed.Facultad de Ciencias Naturales y Muse

A general framework for nonholonomic mechanics: Nonholonomic Systems on Lie affgebroids

This paper presents a geometric description of Lagrangian and Hamiltonian systems on Lie affgebroids subject to affine nonholonomic constraints. We define the notion of nonholonomically constrained system, and characterize regularity conditions that guarantee that the dynamics of the system can be obtained as a suitable projection of the unconstrained dynamics. It is shown that one can define an almost aff-Poisson bracket on the constraint AV-bundle, which plays a prominent role in the description of nonholonomic dynamics. Moreover, these developments give a general description of nonholonomic systems and the unified treatment permits to study nonholonomic systems after or before reduction in the same framework. Also, it is not necessary to distinguish between linear or affine constraints and the methods are valid for explicitly time-dependent systems.Comment: 50 page