Suscetibilidade de Spodoptera Frugiperda a isolados geográficos de um vírus de poliedrose nuclear

O presente trabalho objetivou verificar a suscetibilidade de larvas de segundo ínstar de Spodoptera frugiperda (Smith, 1797) a sete isolados geográficos de um vírus de poliedrose nuclear (VPN), conduzindo-se sete bioensaios no Laboratório de Patologia de Insetos da Embrapa-Centro Nacional de Pesquisa de Soja, Londrina. Para cada isolado preparou-se dieta artificial contendo 0, 2x10³, 4x10³, 8x10³, 16x10³, 32x10³ e 64x10³ corpos poliédricos de inclusão (CPI)/mL. Cada dose foi oferecida às larvas em copos de plástico de 50 mL, sob condições controladas (temperatura: 26±2ºC; umidade relativa: 60±10%; fotófase:14 horas). A análise (Probits) realizada sobre o somatório de larvas mortas (contadas, diariamente, do quinto ao décimo quarto dia após a inoculação) mostrou, com base na ausência de sobreposição das amplitudes dos intervalos de confiança das concentrações letais médias (CL50), que: o isolado de Sertaneja, PR (5.631 CPI/mL), foi o mais virulento; o da Guatemala (11.520 CPI/mL) equivaleu aos de Ponta Grossa, PR (14.184 CPI/mL), Argentina (15.891 CPI/mL) e Alabama, EUA (17.558 CPI/mL), mas foi superior aos isolados de Louisiana, EUA (19.325 CPI/mL) e Sete Lagoas, MG (25.310 CPI/mL). A variação do tempo letal médio, de 8,3 a 10 dias, não foi significativa em relação aos isolados.

Efeito do tamanho do folículo na maturação nuclear e citoplasmática de ovócitos de fêmeas zebuínas

Este estudo avaliou o efeito do tamanho do folículo na capacidade dos ovócitos de sofrerem maturação nuclear e citoplasmática. Ovários de vacas Nelore (Bos indicus) foram coletados logo após o abate, e os complexos cúmulus-ovócitos foram aspirados de folículos de diferentes categorias, e classificados de acordo com seus diâmetros em: 1-2 mm, 3-5 mm, 6-8 mm e > ou = 9 mm. A medida do diâmetro e a fixação dos ovócitos para avaliação do estádio nuclear antes da maturação foram feitas logo após a aspiração. Ovócitos morfologicamente viáveis foram maturados, fecundados e cultivados in vitro. Os ovócitos obtidos de folículos de 1-2 mm apresentaram menor diâmetro (P<0,01) do que os dos demais grupos. Antes da maturação, 89,8%, 90,1%, 85,7% e 100% dos ovócitos provenientes de folículos de 1-2, 3-5, 6-8 e > ou = 9 mm de diâmetro, respectivamente, apresentavam vesícula germinativa. O tamanho do folículo não influenciou (P<0,05) a taxa de maturação nuclear. A porcentagem de ovócitos que chegaram a metáfase II foi de 88,8%, 87,8%, 92,9% e 100% no que se refere aos ovócitos de folículos de 1-2, 3-5, 6-8 e > ou = 9 mm, respectivamente. As taxas de penetração e clivagem foram semelhantes (P>0,05) nos grupos de 1-2 mm (93,4% e 81,9%), 3-5 mm (90,7% e 79,6%), 6-8 mm (91,3% e 77,8%) e > ou = 9 mm (92,0% e 78,3%). Da mesma forma, não houve diferenças (P>0,05) entre as categorias de folículos no que se refere às taxas de polispermia, descondensação da cabeça do espermatozóide e formação de pro-núcleos. Os resultados deste estudo demonstram que na espécie B. indicus, folículos com diâmetro de 1 mm até > ou = 9 mm não influenciaram a capacidade dos ovócitos de reiniciar e completar a meiose e de clivar após maturação e fecundação in vitro.

Controle da lagarta-da-soja com aplicações de seu vírus de poliedrose nuclear por vias aérea e terrestre

De 1983 a 1988 foram conduzidos, na região de Dourados, MS, seis experimentos e três campos-piloto, objetivando controlar a lagarta Anticarsia gemmatalis Hübner, 1818, com aplicações aérea e terrestre de seu vírus de poliedrose nuclear (VPN Ag). Cem lagartas equivalentes (LE) de VPN Ag associadas a óleo de soja, melaço de cana-de-açúcar e água, foram aplicadas com avião agrícola equipado com Micronair. Os preparados oleosos (5,5 e 5 L ha-1) e com melaço (10 L ha-1) controlaram 75-89% e 79-96% das lagartas, respectivamente. A suspensão aquosa de 3 L ha-1 foi ineficaz, porém as de 15, 20 e 25 L ha-1 controlaram de 81% a 90% das lagartas. Cinqüenta LE, aplicadas com avião agrícola (3 L ha-1) ou atomizador (15 L ha-1), foram ineficientes. Aplicações da mesma dose com pulverizador de barra (134 e 150 L ha-1) proporcionaram controle de 87% e 90%, respectivamente, e com avião (15, 20 e 25 L ha-1), entre 93% e 98%. Aplicações aéreas de 50 LE com óleo de soja (5 L ha-1) ou melaço (10 L ha-1) foram eficientes (86-88% e 99%, respectivamente). Aplicações aéreas de suspensões aquosas e formulado oleoso, em campos-piloto, confirmaram os resultados experimentais.

An Evaluation of the Troxler 3241-B Nuclear Asphalt Gauge, MLR-85-11, 1986

The Troxler 3241-B Asphalt Content Gauge is intended for rapidly determining the bitumen content of bituminous paving mixtures. A 300 Millicurie Americuium 241: Beryllium source emitts neutrons which are affected by the hydrogen in the mix. The affected neutrons are detected by Helium 3 detectors, counted and computed into a percentage bitumen of the asphalt mix. The current methods of determining the bitumen content of bituminous paving mixtures requires the use of potentially hazardous chemicals and several hours of testing time. When extracted aggregates are not needed, determination of the bitumen content of a paving mixture by the nuclear method may be easier, quicker and potentially safer. The objective of the project is to study the accuracy of the Troxler 3241-B Nuclear Asphalt Content Gauge in measuring the asphalt cement (AC) content of asphalt concrete mixtures produced with different asphalt cements and different aggregates.

Targeting receptor activator of nuclear factor-kappa B as a new therapy for bone metastasis in non-small cell lung cancer.

PURPOSE OF REVIEW: The review aims at comprehensively discussing our current knowledge on bone metastases incidence in non-small cell lung cancer (NSCLC), their related complications as well as clinical impact in patients suffering from advanced disease. RECENT FINDINGS: After evoking the use of zoledronic acid as the established standard of care until recently, the new class of drugs available to prevent skeletal related events and targeting receptor activator of nuclear factor-kappa B (RANK) will be emphasized, reporting on denosumab clinical trials, a RANK-ligand (RANKL) targeting monoclonal antibody. Biological hypothesis regarding their mechanisms of action as well a potential direct impact on tumor cells are described according to the most recent laboratory as well as hypothesis-generating clinical data. SUMMARY: Targeting the RANK pathway is an efficient way to prevent complications of bone metastases in NSCLC. Interesting additional direct effects on tumor biology and evolution are being analyzed and prospectively assessed in clinical trials.

Transition from hemifusion to pore opening is rate limiting for vacuole membrane fusion.

Fusion pore opening and expansion are considered the most energy-demanding steps in viral fusion. Whether this also applies to soluble N-ethyl-maleimide sensitive fusion protein attachment protein receptor (SNARE)- and Rab-dependent fusion events has been unknown. We have addressed the problem by characterizing the effects of lysophosphatidylcholine (LPC) and other late-stage inhibitors on lipid mixing and pore opening during vacuole fusion. LPC inhibits fusion by inducing positive curvature in the bilayer and changing its biophysical properties. The LPC block reversibly prevented formation of the hemifusion intermediate that allows lipid, but not content, mixing. Transition from hemifusion to pore opening was sensitive to guanosine-5'-(gamma-thio)triphosphate. It required the vacuolar adenosine triphosphatase V0 sector and coincided with its transformation. Pore opening was rate limiting for the reaction. As with viral fusion, opening the fusion pore may be the most energy-demanding step for intracellular, SNARE-dependent fusion reactions, suggesting that fundamental aspects of lipid mixing and pore opening are related for both systems.

Estrogen-dependent in vitro transcription from the vitellogenin promoter in liver nuclear extracts.

One approach to analyzing the molecular mechanisms of gene expression in vivo is to reconstitute these events in cell-free systems in vitro. Although there is some evidence for tissue-specific transcription in vitro, transcriptionally active extracts that mimic a steroid hormone-dependent enhancement of transcription have not been described. In the study reported here, nuclear extracts of liver from the frog Xenopus laevis were capable of estrogen-dependent induction of a homologous vitellogenin promoter that contained the estrogen-responsive element.

Nuclear magnetic resonance

This article reviews the principles and methods of nuclear magnetic resonance spectroscopy, and gives examples of applications carried out at ourFacility, which illustrate the capabilities of the technique.

Peroxisome proliferator-activated receptors: a nuclear receptor signaling pathway in lipid physiology.

Peroxisome proliferator-activated receptors (PPARs) are lipid-activated transcription factors that belong to the steroid/thyroid/retinoic acid receptor superfamily. All their characterized target genes encode proteins that participate in lipid homeostasis. The recent finding that antidiabetic thiazolidinediones and adipogenic prostanoids are ligands of one of the PPARs reveals a novel signaling pathway that directly links these compounds to processes involved in glucose homeostasis and lipid metabolism including adipocyte differentiation. A detailed understanding of this pathway could designate PPARs as targets for the development of novel efficient treatments for several metabolic disorders.

Martensitic phase transformation in rapidly solidified Mn50Ni40In10 alloy ribbons

Heusler alloy Mn50Ni40In10 was produced as preferentially textured ribbon flakes by melt spinning, finding the existence of martensitic-austenic transformation with both phases exhibiting ferromagnetic ordering. A microcrystalline three-layered microstructure of ordered columnar grains grown perpendicularly to ribbon plane was formed between two thin layers of smaller grains. The characteristic temperatures of the martensitic transformation were MS=213 K, Mf=173 K, AS=222 K, and Af=243 K. Austenite phase shows a cubic L21 structure (a=0.6013(3) nm at 298 K and a Curie point of 311 K), transforming into a modulated fourteen-layer modulation monoclinic martensite

Agrobacterium-mediated genetic transformation of 'Hamlin' sweet orange

The development and optimization of efficient transformation protocols is essential in new citrus breeding programs, not only for rootstock, but also for scion improvement. Transgenic 'Hamlin' sweet orange (Citrus sinensis (L.) Osbeck) plants were obtained by Agrobacterium tumefaciens-mediated transformation of epicotyl segments collected from seedlings germinated in vitro. Factors influencing genetic transformation efficiency were evaluated including seedling incubation conditions, time of inoculation with Agrobacterium and co-culture conditions. Epicotyl segments were adequate explants for transformation, regenerating plants by direct organogenesis. Higher percentage of transformation was obtained with explants collected from seedlings germinated in darkness, transferred to 16 hours photoperiod for 2-3 weeks, and inoculated with Agrobacterium for 15-45 min. The best co-culture condition was the incubation of the explants in darkness, for three days in culture medium supplemented with 100 muM of acetosyringone. Genetic transformation was confirmed by performing beta-glucoronidase (GUS) assays and, subsequently, by PCR amplification for the nptII and GUS genes.

Polychlorinated trityl radicals for dynamic nuclear polarization: the role of chlorine nuclei

Polychlorinated trityl radicals bearing carboxylate substituents are water soluble persistent radicals that can be used for dynamic nuclear polarization. In contrast to other trityl radicals, the polarization mechanism differs from the classical solid effect. DFT calculations performed to rationalize this behaviour support the hypothesis that polarization is transferred from the unpaired electron to chlorine nuclei and from these to carbon by spin diffusion. The marked differences observed between neutral and anionic forms of the radical will be discussed.

Improving the prediction of the functional impact of cancer mutations by baseline tolerance transformation

High-throughput prioritization of cancer-causing mutations (drivers) is a key challenge of cancer genome projects, due to the number of somatic variants detected in tumors. One important step in this task is to assess the functional impact of tumor somatic mutations. A number of computational methods have been employed for that purpose, although most were originally developed to distinguish disease-related nonsynonymous single nucleotide variants (nsSNVs) from polymorphisms. Our new method, transformed Functional Impact score for Cancer (transFIC), improves the assessment of the functional impact of tumor nsSNVs by taking into account the baseline tolerance of genes to functional variants.

A nuclear defect in the 4p16 region predisposes to multiple mitochondrial DNA deletions in families with Wolfram syndrome.

Wolfram syndrome is a progressive neurodegenerative disorder transmitted in an autosomal recessive mode. We report two Wolfram syndrome families harboring multiple deletions of mitochondrial DNA. The deletions reached percentages as high as 85-90% in affected tissues such as the central nervous system of one patient, while in other tissues from the same patient and from other members of the family, the percentages of deleted mitochondrial DNA genomes were only 1-10%. Recently, a Wolfram syndrome gene has been linked to markers on 4p16. In both families linkage between the disease locus and 4p16 markers gave a maximum multipoint lod score of 3.79 at theta = 0 (Pi<0.03) with respect to D4S431. In these families, the syndrome was caused by mutations in this nucleus-encoded gene which deleteriously interacts with the mitochondrial genome. This is the first evidence of the implication of both genomes in a recessive disease.