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901.
Lóry Viktória Balážová Lucia Kršková Katarína Horváthová Ľubica Olszanecki Rafal Suski Maciej Zórad Štefan 《Journal of physiology and biochemistry》2019,75(3):351-365
Journal of Physiology and Biochemistry - There is a gap in the knowledge regarding regulation of local renin–angiotensin system (RAS) in skeletal muscle during development of obesity and... 相似文献
902.
903.
Luisa Cigliano Maria Stefania Spagnuolo Raffaella Crescenzo Rosa Cancelliere Lucia Iannotta Arianna Mazzoli Giovanna Liverini Susanna Iossa 《Molecular neurobiology》2018,55(4):2869-2883
The drastic increase in the consumption of fructose encouraged the research to focus on its effects on brain physio-pathology. Although young and adults differ largely by their metabolic and physiological profiles, most of the previous studies investigated brain disturbances induced by long-term fructose feeding in adults. Therefore, we investigated whether a short-term consumption of fructose (2 weeks) produces early increase in specific markers of inflammation and oxidative stress in the hippocampus of young and adult rats. After the high-fructose diet, plasma lipopolysaccharide and tumour necrosis factor (TNF)-alpha were found significantly increased in parallel with hippocampus inflammation, evidenced by a significant rise in TNF-alpha and glial fibrillar acidic protein concentrations in both the young and adult groups. The fructose-induced inflammatory condition was associated with brain oxidative stress, as increased levels of lipid peroxidation and nitro-tyrosine were detected in the hippocampus. The degree of activation of the protein kinase B, extracellular signal-regulated kinase 1/2, and insulin receptor substrate 1 pathways found in the hippocampus after fructose feeding indicates that the detrimental effects of the fructose-rich diet might largely depend on age. Mitochondrial function in the hippocampus, together with peroxisome proliferator-activated receptor gamma coactivator 1-alpha content, was found significantly decreased in fructose-treated adult rats. In vitro studies with BV-2 microglial cells confirmed that fructose treatment induces TNF-alpha production as well as oxidative stress. In conclusion, these results suggest that unbalanced diet, rich in fructose, may be highly deleterious in young people as in adults and must be strongly discouraged for the prevention of diet-associated neuroinflammation and neurological diseases. 相似文献
904.
Anusha Poosapati Emily Gregory Wade M. Borcherds Lucia B. Chemes Gary W. Daughdrill 《Journal of molecular biology》2018,430(16):2389-2402
The relationship between helical stability and binding affinity was examined for the intrinsically disordered transactivation domain of the myeloblastosis oncoprotein, c-Myb, and its ordered binding partner, KIX. A series of c-Myb mutants was designed to either increase or decrease helical stability without changing the binding interface with KIX. This included a complimentary series of A, G, P, and V mutants at three non-interacting sites. We were able to use the glycine mutants as a reference state and show a strong correlation between binding affinity and helical stability. The intrinsic helicity of c-Myb is 21%, and helicity values of the mutants ranged from 8% to 28%. The c-Myb helix is divided into two conformationally distinct segments. The N-terminal segment, from K291–L301, has an average helicity greater than 60% and the C-terminal segment, from S304–L315, has an average helicity less than 10%. We observed different effects on binding when these two segments were mutated. Mutants in the N-terminal segment that increased helicity had no effect on the binding affinity to KIX, while helix destabilizing glycine and proline mutants reduced binding affinity by more than 1 kcal/mol. Mutants that either increased or decreased helical stability in the C-terminal segment had almost no effect on binding. However, several of the mutants reveal the presence of multiple conformations accessible in the bound state based on changes in enthalpy and linkage analysis of binding free energies. These results may explain the high level of sequence identity (> 90%), even at non-interacting sites, for c-Myb homologues. 相似文献
905.
Zachary C. Campbell Lucia M. Acosta-Gamboa Nirman Nepal Argelia Lorence 《Phytochemistry Reviews》2018,17(6):1329-1343
High-throughput plant phenotyping has been advancing at an accelerated rate as a response to the need to fill the gap between genomic information and the plasticity of the plant phenome. During the past decade, North America has seen a stark increase in the number of phenotyping facilities, and these groups are actively contributing to the generation of high-dimensional, richly informative datasets about the phenotype of model and crop plants. As both phenomic datasets and analysis tools are made publicly available, the key to engineering more resilient crops to meet global demand is closer than ever. However, there are a number of bottlenecks that must yet be overcome before this can be achieved. In this paper, we present an overview of the most commonly used sensors that empower digital phenotyping and the information they provide. We also describe modern approaches to identify and characterize plants that are resilient to common abiotic and biotic stresses that limit growth and yield of crops. Of interest to researchers working in plant biochemistry, we also include a section discussing the potential of these high-throughput approaches in linking phenotypic data with chemical composition data. We conclude by discussing the main bottlenecks that still remain in the field and the importance of multidisciplinary teams and collaboration to overcome those challenges. 相似文献
906.
907.
Khaled Abbes Antonio Biondi Alican Kurtulus Michele Ricupero Agatino Russo Gaetano Siscaro Brahim Chermiti Lucia Zappalà 《PloS one》2015,10(9)
We studied the acute toxicity and the sublethal effects, on reproduction and host-killing activity, of four widely used insecticides on the generalist parasitoid Bracon nigricans (Hymenoptera: Braconidae), a natural enemy of the invasive tomato pest, Tuta absoluta (Lepidoptera: Gelechiidae). Laboratory bioassays were conducted applying maximum insecticide label rates at three constant temperatures, 25, 35 and 40°C, considered as regular, high and very high, respectively. Data on female survival and offspring production were used to calculate population growth indexes as a measure of population recovery after pesticide exposure. Spinetoram caused 80% mortality at 25°C and 100% at higher temperatures, while spinosad caused 100% mortality under all temperature regimes. Cyantraniliprole was slightly toxic to B. nigricans adults in terms of acute toxicity at the three temperatures, while it did not cause any sublethal effects in egg-laying and host-killing activities. The interaction between the two tested factors (insecticide and temperature) significantly influenced the number of eggs laid by the parasitoid, which was the lowest in the case of females exposed to chlorantraniliprole at 35°C. Furthermore, significantly lower B. nigricans demographic growth indexes were estimated for all the insecticides under all temperature conditions, with the exception of chlorantraniliprole at 25°C. Our findings highlight an interaction between high temperatures and insecticide exposure, which suggests a need for including natural stressors, such as temperature, in pesticide risk assessments procedures. 相似文献
908.
Macedo CS Schwarz RT Todeschini AR Previato JO Mendonça-Previato L 《Memórias do Instituto Oswaldo Cruz》2010,105(8):949-956
Human malignant malaria is caused by Plasmodium falciparum and accounts for almost 900,000 deaths per year, the majority of which are children and pregnant women in developing countries. There has been significant effort to understand the biology of P. falciparum and its interactions with the host. However, these studies are hindered because several aspects of parasite biology remain controversial, such as N- and O-glycosylation. This review describes work that has been done to elucidate protein glycosylation in P. falciparum and it focuses on describing biochemical evidence for N- and O-glycosylation. Although there has been significant work in this field, these aspects of parasite biochemistry need to be explored further. 相似文献
909.
Evaluation of fungal and yeast diversity in Slovakian wine-related microbial communities 总被引:1,自引:0,他引:1
Barbara Brežná Katarína Ženišová Katarína Chovanová Viera Chebeňová Lucia Kraková Tomáš Kuchta Domenico Pangallo 《Antonie van Leeuwenhoek》2010,98(4):519-529
Since the yeast flora of Slovakian enology has not previously been investigated by culture-independent methods, this approach was applied to two most common cultivars Frankovka (red wine) and Veltlin (white wine), and complemented by cultivation. Model samples included grapes, initial must, middle fermenting must and must in the end-fermentation phase. The cultured isolates were characterized by length polymorphism of rDNA spacer two region using fluorescence PCR and capillary electrophoresis (f-ITS PCR), and some were identified by sequencing. The microbial DNA extracted directly from the samples without cultivation was analysed by f-ITS PCR, amplicons were cloned and sequenced. The use of universal fungal primers led to detection of both yeasts and filamentous fungi. The amplicon of highest intensity and present in all the samples corresponded to Hanseniaspora uvarum. Other species demonstrated by both approaches included Saccharomyces sp., Metschnikowia pulcherrima or M. chrysoperlae, Candida zemplinina, Cladosporium cladosporioides, Botryotinia fuckeliana, Pichia anomala, Candida railenensis, Cryptococcus magnus, Metschnikowia viticola or Candida kofuensis, Pichia kluyveri or Pichia fermentas, Pichia membranifaciens, Aureobasidium pullulans, Alternaria alternata, Erysiphe necator, Rhodotorula glutinis, Issatchenkia terricola and Debaryomyces hansenii. Endemism of Slovakian enological yeasts was suggested on the level of minor genetic variations of the known species and probably not accounting for novel species. The prevalence of H. uvarum over Saccharomyces sp. in the samples was indicated. This is the first culture-independent study of Slovakian enology and the first time f-ITS PCR profiling was used on wine-related microbial communities. 相似文献
910.
Lucia Mauri Luca Barone Muna Al Oum Alessandra Del Longo Elena Piozzi Emanuela Manfredini Franco Stanzial Francesco Benedicenti Silvana Penco Maria Cristina Patrosso 《Gene》2014