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Despite the growing number of genomes published or currently being sequenced, there is a relative paucity of software for functional classification of newly discovered genes and their assignment to metabolic pathways. Available software for such analyses has a very steep learning curve and requires the installation, configuration, and maintenance of large amounts of complex infrastructure, including complementary software and databases. Many such tools are restricted to one or a few data sources and classification schemes. In this work, we report an automated system for gene annotation and metabolic pathway reconstruction (ASGARD), which was designed to be powerful and generalizable, yet simple for the biologist to install and run on centralized, commonly available computers. It avoids the requirement for complex resources such as relational databases and web servers, as well as the need for administrator access to the operating system. Our methodology contributes to a more rapid investigation of the potential biochemical capabilities of genes and genomes by the biological researcher, and is useful in biochemical as well as comparative and evolutionary studies of pathways and networks.  相似文献   
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In this study, we prepared translucid hydrogels with different concentrations of silk fibroin, extracted from raw silk fibers, and used them as a matrix to incorporate the photosensitizer 5-(4-aminophenyl)-10,15,20-tris-(4-sulphonatophenyl) porphyrin trisodium for application in photodynamic therapy (PDT). The hydrogels obtained were characterized by rheology, spectrophotometry, and scattering techniques to elucidate the factors involved in the formation of the hydrogel, and to characterize the behavior of silk fibroin (SF) after incorporating of the porphyrin to the matrix. The rheology results demonstrated that the SF hydrogels had a shear thinning behavior. In addition, we were able to verify that the structure of the material was able to be recovered over time after shear deformation. The encapsulation of porphyrins in hydrogels leads to the formation of self-assembled peptide nanostructures that prevent porphyrin aggregation, thereby greatly increasing the generation of singlet oxygen. Also, our findings suggest that porphyrin can diffuse out of the hydrogel and permeate the outer skin layers. This evidence suggests that SF hydrogels could be used as porphyrin encapsulation and as a drug carrier for the sustained release of photosensitizers for PDT.  相似文献   
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Economic Botany - We aim to evaluate whether socioeconomic factors influence the knowledge, use, preference, and consumption of firewood in a rural community in Northeast Brazil. We conducted...  相似文献   
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Photosynthesis Research - This study examined whether drought sensitivity in açaí (Euterpe oleracea Mart.) is associated with reductions in photosynthesis and increasing oxidative stress...  相似文献   
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The objective of this study was to evaluate the effects of different natural ventilation systems and explant types on the growth and volatile compound content of Lippia gracilis cultured in vitro. The treatments consisted of four membrane systems (without membrane, with one, two, and four porous membranes) and two explant types (nodal segments with and without a pair of leaves). The evaluation of growth, photosynthetic pigments and chemical analysis of the volatile fraction were performed at 35 days of cultivation in half strength MS basal medium. Natural ventilation systems significantly influenced the in vitro growth and volatile fraction of L. gracilis. Explants with a pair of leaves obtained the best experimental responses. The natural ventilation system with four membranes provided the best growth parameters and leaf area response of L. gracilis explants with leaves. The photosynthetic pigments decreased with an increase in the number of porous membranes in the culture flask. Variations in the number, content, and profile of volatile compounds under the influence of natural ventilation systems were observed. Major constituents such as ρ-cymene, γ-terpinene, thymol, carvacrol, and E-caryophyllene, regardless of experimental conditions, were identified. The highest carvacrol and thymol contents were observed in plantlets grown in culture flasks with four porous membranes. To maximize the content of carvacrol and thymol from the in vitro culture of L. gracilis, explants with a pair of leaves and four porous membranes in culture flasks are recommended for use.

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Rhodotorula species are emerging as opportunistic pathogens, causing catheter-associated fungemia in patients with compromised immunity. R. mucilaginosa is considered the most common species involved in human infections. Correct identification and susceptibility testing of Rhodotorula isolates recovered from the blood stream or central nervous system are essential to determine the best management of this unusual infection. The antifungal susceptibility tests showed that Rhodotorula was susceptible to low concentrations of amphotericin B (AMB) but was less susceptible to voriconazole. Combinations of AMB plus several non-antifungal medications were evaluated against 35 susceptible (Rm AMB-S) and resistant (Rm AMB-R) clinical Rhodotorula isolates using the broth microdilution checkerboard technique. We showed that in vitro exposure to increasing concentrations of AMB changed the susceptibility profile to these strains, which were named the Rm AMB-R group. The most synergistic interactions were AMB?+?simvastatin, followed by AMB?+?amlodipine and AMB?+?warfarin. Synergism and antagonism were observed in both groups for the combination AMB?+?cyclosporine A. AMB combined with a fluoroquinolone (AMB?+?levofloxacin) also demonstrated antagonism for the Rm AMB-S strains, but a high percentage of synergistic interactions was observed for the Rm AMB-R group. A combination drug approach can provide a different strategy to treat infections caused by AMB-resistant R. mucilaginosa.

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