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排序方式: 共有1037条查询结果,搜索用时 46 毫秒
51.
Paola Zanetta Diletta Francesca Squarzanti Alessia di Coste Roberta Rolla Paolo Aluffi Valletti Massimiliano Garzaro Valeria DellEra Angela Amoruso Marco Pane Barbara Azzimonti 《International journal of molecular sciences》2022,23(24)
The human oral pathobionts Aggregatibacter actinomycetemcomitans, Streptococcus mitis and Streptococcus mutans, in dysbiosis-promoting conditions, lead to oral infections, which also represent a threat to human systemic health. This scenario may be worsened by antibiotic misuse, which favours multi-drug resistance, making the research on pathogen containment strategies more than crucial. Therefore, we aimed to in vitro select the most promising probiotic strains against oral pathogen growth, viability, biofilm formation, and co-aggregation capacity, employing both the viable probiotics and their cell-free supernatants (CFSs). Interestingly, we also assessed probiotic efficacy against the three-pathogen co-culture, mimicking an environment similar to that in vivo. Overall, the results showed that Lactobacillus CFSs performed better than the Bifidobacterium, highlighting Limosilactobacillus reuteri LRE11, Lacticaseibacillus rhamnosus LR04, Lacticaseibacillus casei LC04, and Limosilactobacillus fermentum LF26 as the most effective strains, opening the chance to deeper investigation of their action and CFS composition. Altogether, the methodologies presented in this study can be used for probiotic efficacy screenings, in order to better focus the research on a viable probiotic, or on its postbiotics, suitable in case of infections. 相似文献
52.
Claudia Penna Saveria Femmin Fabrizio Caldera Alberto Rubin Pedrazzo Claudio Cecone Edoardo Alfì Stefano Comit Takanobu Higashiyama Francesco Trotta Pasquale Pagliaro Roberta Cavalli 《International journal of molecular sciences》2021,22(8)
Heart failure (HF) prevalence is increasing among the aging population, and the mortality rate remains unacceptably high despite improvements in therapy. Myocardial ischemia (MI) and, consequently, ischemia/reperfusion injury (IRI), are frequently the basis of HF development. Therefore, cardioprotective strategies to limit IRI are mandatory. Nanocarriers have been proposed as alternative therapy for cardiovascular disease. Controlled reoxygenation may be a promising strategy. Novel nanocarriers, such as cyclic nigerosyl-nigerose (CNN), can be innovative tools for oxygen delivery in a controlled manner. In this study we analyzed new CNN-based formulations as oxygen nanocarriers (O2-CNN), and compared them with nitrogen CNN (N2-CNN). These different CNN-based formulations were tested using two cellular models, namely, cardiomyoblasts (H9c2), and endothelial (HMEC) cell lines, at different concentrations. The effects on the growth curve during normoxia (21% O2, 5% CO2 and 74% N2) and their protective effects during hypoxia (1% O2, 5% CO2 and 94% N2) and reoxygenation (21% O2, 5% CO2 and 74% N2) were studied. Neither O2-CNN nor N2-CNN has any effect on the growth curve during normoxia. However, O2-CNN applied before hypoxia induces a 15–30% reduction in cell mortality after hypoxia/re-oxygenation when compared to N2-CNN. O2-CNN showed a marked efficacy in controlled oxygenation, which suggests an interesting potential for the future medical application of soluble nanocarrier systems for MI treatment. 相似文献
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Sueva Cantalupo Vito Alessandro Lasorsa Roberta Russo Immacolata Andolfo Giuseppe DAlterio Barbara Eleni Rosato Giulia Frisso Pasquale Abete Gian Marco Cassese Giuseppe Servillo Ivan Gentile Carmelo Piscopo Matteo Della Monica Giuseppe Fiorentino Giuseppe Russo Pellegrino Cerino Carlo Buonerba Biancamaria Pierri Massimo Zollo Achille Iolascon Mario Capasso 《International journal of molecular sciences》2021,22(10)
Genome-wide association studies (GWAS) found locus 3p21.31 associated with severe COVID-19. CCR5 resides at the same locus and, given its known biological role in other infection diseases, we investigated if common noncoding and rare coding variants, affecting CCR5, can predispose to severe COVID-19. We combined single nucleotide polymorphisms (SNPs) that met the suggestive significance level (P ≤ 1 × 10−5) at the 3p21.31 locus in public GWAS datasets (6406 COVID-19 hospitalized patients and 902,088 controls) with gene expression data from 208 lung tissues, Hi-C, and Chip-seq data. Through whole exome sequencing (WES), we explored rare coding variants in 147 severe COVID-19 patients. We identified three SNPs (rs9845542, rs12639314, and rs35951367) associated with severe COVID-19 whose risk alleles correlated with low CCR5 expression in lung tissues. The rs35951367 resided in a CTFC binding site that interacts with CCR5 gene in lung tissues and was confirmed to be associated with severe COVID-19 in two independent datasets. We also identified a rare coding variant (rs34418657) associated with the risk of developing severe COVID-19. Our results suggest a biological role of CCR5 in the progression of COVID-19 as common and rare genetic variants can increase the risk of developing severe COVID-19 by affecting the functions of CCR5. 相似文献
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Tracy Jessica L.; Robins Richard W.; Schriber Roberta A. 《Canadian Metallurgical Quarterly》2009,9(4):554
In 2 studies, the authors developed and validated of a new set of standardized emotion expressions, which they referred to as the University of California, Davis, Set of Emotion Expressions (UCDSEE). The precise components of each expression were verified using the Facial Action Coding System (FACS). The UCDSEE is the first FACS-verified set to include the three “self-conscious” emotions known to have recognizable expressions (embarrassment, pride, and shame), as well as the 6 previously established “basic” emotions (anger, disgust, fear, happiness, sadness, and surprise), all posed by the same 4 expressers (African and White males and females). This new set has numerous potential applications in future research on emotion and related topics. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
56.
Fernandez A Wendt JO Cenni R Young RS Witten ML 《The Science of the total environment》2002,287(3):265-274
Airborne particulate matter (PM) is an important environmental issue because of its association with acute respiratory distress in humans, although the specific particle characteristics that cause lung damage have yet to be identified. Particle size, acid aerosols, water-soluble transition metals (e.g. Cu, Fe, V, Ni and Zn), polyaromatic hydrocarbons, and particle composition are the focus of several popular hypotheses addressing respiratory distress. All of the above mentioned characteristics are contained in PM generated from the combustion of both pulverized coal, and biomass, including dried municipal sewage sludge (MSS). In this investigation, we report results from collaborative interdisciplinary research on the inhalation health risks caused by particles emitted from the co-combustion of municipal sewage sludge (MSS) and coal. A solid particle resuspension system was implemented to resuspend ash particles. Mice were exposed to resuspended coal and MSS/coal ash particles. Mice exposed to MSS/coal ash particulate demonstrated significant increases in lung permeability, a marker of the early stages of pathological lung injury, while the mice exposed to coal-only ash did not. These results show that the composition of particles actually inhaled is important in determining lung damage. Zinc was significantly more concentrated in the MSS/coal ash than coal ash particles and the pH of these particles did not differ significantly. Specifically, an MSS/coal mixture, when burned, emits particles that may cause significantly more lung damage than coal alone, and that consequently, the use of MSS as a 'green', CO2-neutral replacement fuel should be carefully considered. 相似文献
57.
Giovanni Pioggia Roberta Igliozzi Marcello Ferro Arti Ahluwalia Filippo Muratori Danilo De Rossi 《IEEE transactions on neural systems and rehabilitation engineering》2005,13(4):507-515
It is well documented that the processing of social and emotional information is impaired in people with autism. Recent studies have shown that individuals, particularly those with high functioning autism, can learn to cope with common social situations if they are made to enact possible scenarios they may encounter in real life during therapy. The main aim of this work is to describe an interactive life-like facial display (FACE) and a supporting therapeutic protocol that will enable us to verify if the system can help children with autism to learn, identify, interpret, and use emotional information and extend these skills in a socially appropriate, flexible, and adaptive context. The therapeutic setup consists of a specially equipped room in which the subject, under the supervision of a therapist, can interact with FACE. The android display and associated control system has automatic facial tracking, expression recognition, and eye tracking. The treatment scheme is based on a series of therapist-guided sessions in which a patient communicates with FACE through an interactive console. Preliminary data regarding the exposure to FACE of two children are reported. 相似文献
58.
Substrate age and precipitation effects on Hawaiian forest canopies from spaceborne imaging spectroscopy 总被引:1,自引:0,他引:1
Gregory P. Asner Kimberly M. Carlson Roberta E. Martin 《Remote sensing of environment》2005,98(4):457-467
We used spaceborne imaging spectroscopy provided by the Earth Observing-1 Hyperion sensor to quantify the relative importance of precipitation and substrate age that control ecosystem development and functioning in Metrosideros polymorpha rainforests of Hawaii. Four hyperspectral vegetation indices provided metrics of forest canopy structure, biochemistry and physiology to compare along gradients of annual rainfall (750 to > 6000 mm year− 1) and substrate age (0 to 250,000 years). The canopy greenness index NDVI increased with annual precipitation and substrate age, but saturated in forests with rainfall of 3000 mm year− 1. Precipitation and substrate age were roughly equal contributors to the observed greenness of the forests. A canopy water content index (NDWI) also increased with precipitation and substrate age, but did not reach a maximum until very wet (> 5000 mm year− 1) forest conditions were encountered on the oldest substrates. The water index appears superior to the NDVI in capturing spatial and climate-substrate driven variations in canopy structure. The photochemical reflectance index (PRI) indicated highest light-use efficiency levels in canopies on the most developed substrates and at annual precipitation levels of 3-4500 mm year− 1. A leaf carotenoid index (CRI) suggested a maximum canopy photosynthetic capacity at ∼ 4000 mm rainfall year− 1 on the oldest substrates. These results quantify the sensitivity of rainforest canopies to changing precipitation and soil conditions, and they corroborate plot-scale analyses in native Hawaiian forests ecosystems. Structural and functional studies of remote rainforest regions are possible with spaceborne imaging spectroscopy, and could be used to understand the dynamics of rainforests with climate change. 相似文献
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