Biologia e potencial de Doru luteipes no controle de Spodoptera frugiperda.

0 trabalho foi realizado no Centro Nacional de Pesquisa de Milho c Sorgo (CNPMS), em Sete Lagoas, MG, tendo como objetivo conhecer a biologia e o potencial de Doru luteipes (Scudder, 1876) como predador de ovos e larvas do Spodoptera frugiperda (J.E. Smith, 1797), em condições de laboratório. Estudou-se também, em condições do campo, o efeito do diversos inseticidas sobre o predador. Dos estudos bioecológicos, observou-se que as posturas possuem, em média, 26,6 ovos, e o período de incubação é do 7,31 dias. A fase ninfal variou de 37,1 a 50,1 dias, conforme o tratamento, e a fase adulta, de 83,2 dias para individuos alimentados com ovos, a 143 dias para individuos alimentados com larvas. 0 inseto mostrou urn bom potencial como predador de S. frugiperda, apresentando um consumo diário na fase ninfal de 12, 10 e 8 larvas, conforme estas foram oferecidas isoladamente, com folhas do milho ou com dieta. Na fase adulta, o consumo foi na mesma sequência da anterior, de 21, 19 e 10 larvas. Com relação aos inseticidas testados, os produtos permethrin, deltamethrin e methomyl foram eficientes no controle de S. frugiperda, e praticamente não afetaram o predador. Com base nos resultados, conclue-se que D. luteipes, em condições do laboratório, apresentou-se eficiente no controle de S. frugiperda e possui grande potencial para utilizado no controle deste inseto em milho, em condições do campo

Finite-size effects in roughness distribution scaling

We study numerically finite-size corrections in scaling relations for roughness distributions of various interface growth models. The most common relation, which considers the average roughness $$as scaling factor, is not obeyed in the steady states of a group of ballistic-like models in 2+1 dimensions, even when very large system sizes are considered. On the other hand, good collapse of the same data is obtained with a scaling relation that involves the root mean square fluctuation of the roughness, which can be explained by finite-size effects on second moments of the scaling functions. We also obtain data collapse with an alternative scaling relation that accounts for the effect of the intrinsic width, which is a constant correction term previously proposed for the scaling of$$. This illustrates how finite-size corrections can be obtained from roughness distributions scaling. However, we discard the usual interpretation that the intrinsic width is a consequence of high surface steps by analyzing data of restricted solid-on-solid models with various maximal height differences between neighboring columns. We also observe that large finite-size corrections in the roughness distributions are usually accompanied by huge corrections in height distributions and average local slopes, as well as in estimates of scaling exponents. The molecular-beam epitaxy model of Das Sarma and Tamborenea in 1+1 dimensions is a case example in which none of the proposed scaling relations works properly, while the other measured quantities do not converge to the expected asymptotic values. Thus, although roughness distributions are clearly better than other quantities to determine the universality class of a growing system, it is not the final solution for this task.Comment: 25 pages, including 9 figures and 1 tabl

Core-shell silk hydrogels with spatially tuned conformations as drug delivery system

Hydrogels of spatially controlled physicochemical properties are appealing platforms for tissue engineering and drug delivery. In this study, core-shell silk fibroin (SF) hydrogels of spatially controlled conformation were developed. The core-shell structure in the hydrogels was formed by means of soaking the preformed (enzymatically crosslinked) random coil SF hydrogels in methanol. When increasing the methanol treatment time from 1 to 10 minutes, the thickness of the shell layer can be tuned from about 200 to around 850 µm as measured in wet status. After lyophilization of the rehydrated core-shell hydrogels, the shell layer displayed compact morphology and the core layer presented porous structure, when observed by scanning electron microscopy. The conformation of the hydrogels was evaluated by Fourier transform infrared spectroscopy in wet status. The results revealed that the shell layer possessed dominant β-sheet conformation and the core layer maintained mainly random coil conformation. Enzymatic degradation data showed that the shell layers presented superior stability to the core layer. The mechanical analysis displayed that the compressive modulus of the core-shell hydrogels ranged from around 25 kPa to about 1.1 MPa by increasing the immersion time in methanol. When incorporated with albumin, the core-shell SF hydrogels demonstrated slower and more controllable release profiles compared with the non-treated hydrogel. These core-shell SF hydrogels of highly tuned properties are useful systems as drug delivery system and may be applied as cartilage substitute.This study was funded by the Portuguese Foundation for Science and Technology (FCT) projects Tissue2Tissue (PTDC/CTM/105703/2008) and OsteoCart (PTDC/CTM-BPC/115977/2009), as well as the European Union’s FP7 Programme under grant agreement no. REGPOT-CT2012-316331-POLARIS. Le-Ping Yan was awarded a FCT PhD scholarship (SFRH/BD/ 64717/2009). The FCT distinctions attributed to J.M. Oliveira and A.L. Oliveira under the Investigador FCT program (IF/ 00423/2012) and (IF/00411/2013) are also greatly acknowledged, respectively

Development of a bilayered scaffold based on silk fibroin and silk fibroin/nano-calcium phosphate for osteochondral regeneration

Objectives: Osteochondral defect is a common condtion in clinic. Satisfactory outcomes are rarely achieved by traditional methods. Tissue engineering might be a promising strategy for this hinder. The aim of this study is to mimick the stratified structure of osteochondral tissue, by developing a bilayered scaffold for osteochondral regeneration. The developed bilayered scaffold is composed of a porous silk fibroin scaffold as the cartilage-like layer and a porous silk fibroin/nano-calcium phosphate (CaP) scaffold as the bone-like layer

Silk Fibroin/Nano-CaP Bilayered scaffolds for osteochondral tissue engineering

In this study, bilayered silk and silk/nano-CaP scaffolds were developed for osteochondral (OC) tissue engineering. Aqueous silk solution (16 wt.%) was used for preparation of the cartilage-like layer and, for generation of the silk/nano-CaP suspension and the bottom layer (CaP/Silk: 16 wt.%). The scaffolds were formed by using salt-leaching/lyophilization approach. The scanning electron microscopy revealed that the both layers presented porous structure and integrated well. Micro-computed tomography images confirmed that the CaP phase was only retained in the silk/nano-CaP layer. The hydration degree and mechanical properties of the bilayered scaffold were comparable to the ones of each single layer. The apatite crystal formation was limited to the silk/nano-CaP layer, when soaking the scaffold in a simulated body fluid solution, which is a must for the application of the developed scaffolds in OC tissue engineerin

Ortodeoxia recorrente e foramen ovale patente.

Introdução: Foramen ovale patente (FOP) ocorre em até 25% dos adultos saudáveis. Pode favorecer embolização paradoxal, enxaqueca e insuficiência respiratória (IR). Apresenta-se caso de IR e ortodeoxia por shunt direito-esquerdo via FOP sem evidência prévia de aumento da pressão intra-auricular direita. Encerramento do FOP resolveu eficazmente IR. Caso clínico: Homem, 52 anos. Mieloma múltiplo IgA/k diagnosticado um ano antes. Internado por IR hipoxémica grave com ortodeoxia e má resposta à oxigenoterapia, após colocação de cateter venoso central (CVC) na subclávia direita. Referia parestesias e alterações visuais inespecíficas, após manipulações do CVC. Características da IR sugeriam shunt entre circulação pulmonar e sistémica. Sem evidência clínica ou imagiológica de shunt intra-pulmonar. Ecocardiograma transtorácico com contraste: shunt direito- -esquerdo. Ecocardiograma transesofágico: FOP. Cateterismo cardíaco (após resolução espontânea da IR): sem shunt. Uma semana depois recorreu IR grave, que resolveu (bem como queixas neurológicas) com encerramento do FOP. Discussão: IR por shunt intra-cardíaco sem aumento da pressão nas cavidades direitas é de difícil interpretação hemodinâmica. Raros relatos (em adultos) associam esta entidade a anomalias anatómicas, que favorecerão shunt por orientação preferencial do fluxo sanguíneo para o FOP. São exemplos parésia diafragmática direita e ectasia da aorta ascendente, identificadas no doente apresentado. O papel do CVC, colocado imediatamente antes da IR, é especulativo. O completo sucesso terapêutico após encerramento do FOP apoia o diagnóstico. Conclusão: Avaliar correctamente IR (pesquisar ortodeoxia e resposta à oxigenoterapia) permite suspeitar de shunt, que se diagnostica utilizando meios acessíveis, seguros e rentáveis. Shunt intra-cardíaco sem aumento da pressão à direita deve ser considerado porque tem tratamento eficaz. Background: Patent foramen ovale (PFO) occurs in 25% of healthy adults. It can lead to paradoxical embolization, migraine and respiratory failure (RF). The authors present a case of RF and orthodeoxia due to a rightto- left shunt via a PFO without previous elevation of right atrial pressure. Closure of the PFO effectively resolved the RF. Case report: A 52-year-old man, with IgA-k multiple myeloma diagnosed one year before, was admitted for severe hypoxemic RF, with orthodeoxia and poor response to oxygen supplementation, after placement of a central venous catheter (CVC) in the right subclavian vein. The patient reported paresthesia and nonspecific visual changes after manipulation of the CVC. The RF suggested a shunt between the pulmonary and systemic circulations. There was no clinical or radiological evidence of an intrapulmonary shunt. Contrast echocardiography showed a right-to-left shunt and transesophageal echocardiography revealed a PFO. Cardiac catheterization, after spontaneous resolution of the RF, showed no shunt. A week later, severe RF recurred. Complete resolution of respiratory dysfunction and neurological symptoms was seen after PFO closure. Discussion: RF due to an intracardiac shunt without increased right-sided pressure is hemodynamically difficult to interpret. A few reports (in adults) relate this entity to anatomical anomalies, which can lead to a shunt by directing blood flow preferentially to the PFO. Examples include right diaphragmatic paresis and ectasia of the ascending aorta, which were observed in this patient. The role of the CVC, which was placed immediately before the RF, is uncertain. Complete therapeutic success after closure of the PFO supports the diagnosis. Conclusion: Correct evaluation of RF (by investigating orthodeoxia and response to oxygen therapy) enables the suspicion of a shunt, which can be confirmed through simple, safe and cost-effective exams. Intracardiac shunt without increased rightsided pressure should be considered because it can be successfully treatment

Sodium silicate gel as a precursor for the in vitro nucleation and grow of a bone-like apatite coating in compact and porous polymeric structures

In the present work, a new methodology to produce bioactive coatings on the surface of starch-based biodegradable polymers or other polymeric biomaterials is proposed. A sodium silicate gel is employed as an alternative nucleating agent to the more typical bioactive glasses for inducing the formation of a calcium-phosphate (Ca-P) layer. The method has the advantage of being able to coat efficiently both compact materials and porous 3D architectures aimed at being used on tissue replacement applications and as tissue engineering scaffolds. By means of this treatment, it is possible to observe the formation of an apatite-like layer, only after 6 hours of simulated body fluid immersion. For the porous materials, this layer could also be observed inside the pores, clearly covering the cell walls. Furthermore, an increase of the surface hydrophilicity (higher amount of polar groups in the surface) might contribute to the formation of silanol groups that also act as apatite inductors. After 30 days of SBF immersion, the apatite-like films exhibit a partially amorphous nature and the Ca/P ratios became much closer to the value attributed to hydroxyapatite (1.67). The obtained results are very promising for the development of cancellous bone replacement materials and for pre-calcifying bone tissue engineering scaffolds