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991.
This study examined the fish communities of Peri Lagoon in southern Brazil to aid in the development of an effective management plan because the area is under threat from human activities. Sampling of fish fauna, ichthyoplankton and limnological data were compared between sites, differing by habitat type and characteristics such as depth, substratum composition and vegetation type. Results were significantly related to site, with the highest diversity and abundance recorded at shallow vegetated sites. A total of 14 fish species were recorded throughout the lagoon, with the most abundant being Hyphessobrycon luetkenii. Of the 14 species, half were sampled at their larval stage, suggesting a healthy and protected system. Significantly more larvae and eggs were collected during colder months (autumn to winter) and at sites closer to stream flow, possibly owing to increased food sources and habitat protection. This study highlights the importance of Peri Lagoon as a nursery ground for a wide range of fish species, providing essential information for incorporation into the future protection of fish stocks throughout Brazil.  相似文献   
992.
The increased incidence of fungal infections, associated with the widespread use of antifungal drugs, has resulted in the development of resistance, making it necessary to discover new therapeutic alternatives. Among fungal infections, dermatophytoses constitute a serious public health problem, affecting 20–25 % of the world population. Medicinal plants represent an endless source of bioactive molecules, and their volatile and non-volatile extracts are clearly recognized for being the historical basis of therapeutic health care. Because of this, the research on natural products with antifungal activity against dermatophytes has considerably increased in recent years. However, despite the recognized anti-dermatophytic potential of natural products, often advantageous face to commercial drugs, there is still a long way to go until their use in therapeutics. This review attempts to summarize the current status of anti-dermatophytic natural products, focusing on their mechanism of action, the developed pharmaceutical formulations and their effectiveness in human and animal models of infection.  相似文献   
993.
994.
The atmospheric CO2 increase is considered the main cause of global warming. Microalgae are photosynthetic microorganisms that can help in CO2 mitigation and at the same time produce value‐added compounds. In this study, Scenedesmus obliquus , Chlorella vulgaris , and Chlorella protothecoides were cultivated under 0.035 (air), 5 and 10% (v/v) of CO2 concentrations in air to evaluate the performance of the microalgae in terms of kinetic growth parameters, theoretical CO2 biofixation rate, and biomass composition. Among the microalgae studied, S. obliquus presented the highest values of specific growth rate (μ = 1.28 d?1), maximum productivities (P max = 0.28 g L?1d?1), and theoretical CO2 biofixation rates (0.56 g L?1d?1) at 10% CO2. The highest oil content was found at 5% CO2, and the fatty acid profile was not influenced by the concentration of CO2 in the inflow gas mixture and was in compliance with EN 14214, being suitable for biodiesel purposes. The impact of the CO2 on S. obliquus cells’ viability/cell membrane integrity evaluated by the in‐line flow cytometry is quite innovative and fast, and revealed that 86.4% of the cells were damaged/permeabilized in cultures without the addition of CO2.  相似文献   
995.
Immunotherapy targeting aggregated α-synuclein has emerged as a potential treatment strategy against Parkinson’s disease and other α-synucleinopathies. We have developed α-synuclein oligomer/protofibril selective antibodies that reduce toxic α-synuclein in a human cell line and, upon intraperitoneal administration, in spinal cord of transgenic mice. Here, we investigated under which conditions and by which mechanisms such antibodies can be internalized by cells. For this purpose, human neuroglioma H4 cells were treated with either monoclonal oligomer/protofibril selective α-synuclein antibodies, linear epitope monoclonal α-synuclein antibodies, or with a control antibody. The oligomer/protofibril selective antibody mAb47 displayed the highest cellular uptake and was therefore chosen for additional analyses. Next, α-synuclein overexpressing cells were incubated with mAb47, which resulted in increased antibody internalization as compared to non-transfected cells. Similarly, regular cells exposed to mAb47 together with media containing α-synuclein displayed a higher uptake as compared to cells incubated with regular media. Finally, different Fcγ receptors were targeted and we then found that blockage of FcγRI and FcγRIIB/C resulted in reduced antibody internalization. Our data thus indicate that the robust uptake of the oligomer/protofibril selective antibody mAb47 by human CNS-derived cells is enhanced by extracellular α-synuclein and mediated via Fcγ receptors. Altogether, our finding lend further support to the belief that α-synuclein pathology can be modified by monoclonal antibodies and that these can target toxic α-synuclein species in the extracellular milieu. In the context of immunotherapy, antibody binding of α-synuclein would then not only block further aggregation but also mediate internalization and subsequent degradation of antigen–antibody complexes.  相似文献   
996.
Many studies use strategies that allow for the identification of a large number of genes expressed in response to different stress conditions to which the plant is subjected throughout its cycle. In order to obtain accurate and reliable results in gene expression studies, it is necessary to use reference genes, which must have uniform expression in the majority of cells in the organism studied. RNA isolation of leaves and expression analysis in real-time quantitative polymerase chain reaction (RT-qPCR) were carried out. In this study, nine candidate reference genes were tested, actin 11 (ACT11), ubiquitin conjugated to E2 enzyme (UBC-E2), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), beta tubulin (β-tubulin), eukaryotic initiation factor 4α (eIF-4α), ubiquitin 10 (UBQ10), ubiquitin 5 (UBQ5), aquaporin TIP41 (TIP41-Like) and cyclophilin, in two genotypes of rice, AN Cambará and BRS Querência, with different levels of soil moisture (20%, 10% and recovery) in the vegetative (V5) and reproductive stages (period preceding flowering). Currently, there are different softwares that perform stability analyses and define the most suitable reference genes for a particular study. In this study, we used five different methods: geNorm, BestKeeper, ΔCt method, NormFinder and RefFinder. The results indicate that UBC-E2 and UBQ5 can be used as reference genes in all samples and softwares evaluated. The genes β-tubulin and eIF-4α, traditionally used as reference genes, along with GAPDH, presented lower stability values. The gene expression of basic leucine zipper (bZIP23 and bZIP72) was used to validate the selected reference genes, demonstrating that the use of an inappropriate reference can induce erroneous results.  相似文献   
997.
Purpose: The objective of this study is to evaluate the diagnostic properties of urinary biomarkers in adults with ureteropelvic junction obstruction: KIM-1, NGAL, CA19-9, and β2-microglobulin. We also assessed urinary biomarker concentrations following pyeloplasty.

Material and methods: We prospectively studied adults from December 2013 to February 2015. We included 47 patients with a mean age of 38.6?±?12.7 years. Each patient provided four samples of voided urine for biomarker measurement, one at pre-operative consultation and the others at 1, 3, and 6 months of post-operative follow-up. The control group consisted of 40 healthy individuals with no hydronephrosis on ultrasound evaluation.

Results: KIM-1 had an area under the curve of 0.79 (95% CI 0.70–0.89), NGAL 0.71 (95% CI 0.61–0.83), CA19-9 0.70 (95% CI 0.60–0.81), and β2-microgloblin 0.61 (95% CI 0.50–0.73). KIM-1 was the most sensitive marker with a cut-off of 170.4?pg/mg creatinine (sensitivity 91.4%, specificity 59.1%), whereas CA19-9 was the most specific with a cut-off of 51.3?U/mg creatinine (sensitivity 48.9%, specificity 88.0%). Urinary concentrations of biomarkers decreased after pyeloplasty.

Conclusions: The evaluation of urinary biomarkers is useful in adults undergoing pyeloplasty. KIM-1, NGAL, and CA19-9 were elevated and significantly decreased after surgery.  相似文献   

998.
To increase the knowledge of the recombinant cyprosin production process in Saccharomyces cerevisiae cultures, it is relevant to implement efficient bioprocess monitoring techniques. The present work focuses on the implementation of a mid-infrared (MIR) spectroscopy-based tool for monitoring the recombinant culture in a rapid, economic, and high-throughput (using a microplate system) mode. Multivariate data analysis on the MIR spectra of culture samples was conducted. Principal component analysis (PCA) enabled capturing the general metabolic status of the yeast cells, as replicated samples appear grouped together in the score plot and groups of culture samples according to the main growth phase can be clearly distinguished. The PCA-loading vectors also revealed spectral regions, and the corresponding chemical functional groups and biomolecules that mostly contributed for the cell biomolecular fingerprint associated with the culture growth phase. These data were corroborated by the analysis of the samples’ second derivative spectra. Partial least square (PLS) regression models built based on the MIR spectra showed high predictive ability for estimating the bioprocess critical variables: biomass (R 2 = 0.99, RMSEP 2.8%); cyprosin activity (R 2 = 0.98, RMSEP 3.9%); glucose (R 2 = 0.93, RMSECV 7.2%); galactose (R 2 = 0.97, RMSEP 4.6%); ethanol (R 2 = 0.97, RMSEP 5.3%); and acetate (R 2 = 0.95, RMSEP 7.0%). In conclusion, high-throughput MIR spectroscopy and multivariate data analysis were effective in identifying the main growth phases and specific cyprosin production phases along the yeast culture as well as in quantifying the critical variables of the process. This knowledge will promote future process optimization and control the recombinant cyprosin bioprocess according to Quality by Design framework.  相似文献   
999.
Antarctica is one of the most difficult habitats for sustaining life on earth; organisms that live there have developed different strategies for survival. Among these organisms is the green alga Prasiola crispa, belonging to the class Trebouxiophyceae. The literature on P. crispa taxonomy is scarce, and many gaps in the evolutionary relationship with its closest relatives remain. The goal of this study was to analyze the evolutionary relationships between P. crispa and other green algae using plastid and mitochondrial genomes. In addition, we analyzed the synteny conservation of these genomes of P. crispa with those of closely related species. Based on the plastid genome, P. crispa grouped with Prasiolopsis sp. SAG 84.81, another Trebouxiophyceaen species from the Prasiola clade. Based on the mitochondrial genome analysis, P. crispa grouped with other Trebouxiophyceaen species but had a basal position. The structure of the P. crispa chloroplast genome had low synteny with Prasiolopsis sp. SAG 84.81, despite some conserved gene blocks. The same was observed in the mitochondrial genome compared with Coccomyxa subellipsoidea C‐169. We were able to establish the phylogenetic position of P. crispa with other species of Trebouxiophyceae using its genomes. In addition, we described the plasticity of these genomes using a structural analysis. The plastid and mitochondrial genomes of P. crispa will be useful for further genetic studies, phylogenetic analysis and resource protection of P. crispa as well as for further phylogenetic analysis of Trebouxiophyceaen green algae.  相似文献   
1000.
Sixteen yeast isolates identified as belonging to the genus Sugiyamaella were studied in relation to D-xylose fermentation, xylitol production, and xylanase activities. The yeasts were recovered from rotting wood and sugarcane bagasse samples in different Brazilian regions. Sequence analyses of the internal transcribed spacer (ITS) region and the D1/D2 domains of large subunit rRNA gene showed that these isolates belong to seven new species. The species are described here as Sugiyamaella ayubii f.a., sp. nov. (UFMG-CM-Y607T = CBS 14108T), Sugiyamaella bahiana f.a., sp. nov. (UFMG-CM-Y304T = CBS 13474T), Sugiyamaella bonitensis f.a., sp. nov. (UFMG-CM-Y608T = CBS 14270T), Sugiyamaella carassensis f.a., sp. nov. (UFMG-CM-Y606T = CBS 14107T), Sugiyamaella ligni f.a., sp. nov. (UFMG-CM-Y295T = CBS 13482T), Sugiyamaella valenteae f.a., sp. nov. (UFMG-CM-Y609T = CBS 14109T) and Sugiyamaella xylolytica f.a., sp. nov. (UFMG-CM-Y348T = CBS 13493T). Strains of the described species S. boreocaroliniensis, S. lignohabitans, S. novakii and S. xylanicola, isolated from rotting wood of Brazilian ecosystems, were also compared for traits relevant to xylose metabolism. S. valenteae sp. nov., S. xylolytica sp. nov., S. bahiana sp. nov., S. bonitensis sp. nov., S. boreocarolinensis, S. lignohabitans and S. xylanicola were able to ferment d-xylose to ethanol. Xylitol production was observed for all Sugiyamaella species studied, except for S. ayubii sp. nov. All species studied showed xylanolytic activity, with S. xylanicola, S. lignohabitans and S. valenteae sp. nov. having the highest values. Our results suggest these Sugiyamaella species have good potential for biotechnological applications.  相似文献   
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