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101.
Eliane Soler Parra Natalia Baratella Panzoldo Vanessa Helena de Souza Zago Daniel Zanetti Scherrer Fernanda Alexandre Jamal Bakkarat Valeria Sutti Nunes Edna Regina Nakandakare Eder Carlos Rocha Quint?o Wilson Nadruz-Jr Eliana Cotta de Faria Andrei C. Sposito 《PloS one》2014,9(12)
Background
Misclassification of patients as low cardiovascular risk (LCR) remains a major concern and challenges the efficacy of traditional risk markers. Due to its strong association with cholesterol acceptor capacity, high-density lipoprotein (HDL) size has been appointed as a potential risk marker. Hence, we investigate whether HDL size improves the predictive value of HDL-cholesterol in the identification of carotid atherosclerotic burden in individuals stratified to be at LCR.Methods and Findings
284 individuals (40–75 years) classified as LCR by the current US guidelines were selected in a three-step procedure from primary care centers of the cities of Campinas and Americana, SP, Brazil. Apolipoprotein B-containing lipoproteins were precipitated by polyethylene glycol and HDL size was measured by dynamic light scattering (DLS) technique. Participants were classified in tertiles of HDL size (<7.57; 7.57–8.22; >8.22 nm). Carotid intima-media thickness (cIMT) <0.90 mm (80th percentile) was determined by high resolution ultrasonography and multivariate ordinal regression models were used to assess the association between cIMT across HDL size and levels of lipid parameters. HDL-cholesterol was not associated with cIMT. In contrast, HDL size >8.22 nm was independently associated with low cIMT in either unadjusted and adjusted models for age, gender and Homeostasis Model Assessment 2 index for insulin sensitivity, ethnicity and body mass index (Odds ratio 0.23; 95% confidence interval 0.07–0.74, p = 0.013).Conclusion
The mean HDL size estimated with DLS constitutes a better predictor for subclinical carotid atherosclerosis than the conventional measurements of plasma HDL-cholesterol in individuals classified as LCR. 相似文献102.
Crystal N. Johnson John C. Bowers Kimberly J. Griffitt Vanessa Molina Rachel W. Clostio Shaofeng Pei Edward Laws Rohinee N. Paranjpye Mark S. Strom Arlene Chen Nur A. Hasan Anwar Huq Nicholas F. Noriea III D. Jay Grimes Rita R. Colwell 《Applied and environmental microbiology》2012,78(20):7249-7257
Vibrio parahaemolyticus and Vibrio vulnificus, which are native to estuaries globally, are agents of seafood-borne or wound infections, both potentially fatal. Like all vibrios autochthonous to coastal regions, their abundance varies with changes in environmental parameters. Sea surface temperature (SST), sea surface height (SSH), and chlorophyll have been shown to be predictors of zooplankton and thus factors linked to vibrio populations. The contribution of salinity, conductivity, turbidity, and dissolved organic carbon to the incidence and distribution of Vibrio spp. has also been reported. Here, a multicoastal, 21-month study was conducted to determine relationships between environmental parameters and V. parahaemolyticus and V. vulnificus populations in water, oysters, and sediment in three coastal areas of the United States. Because ecologically unique sites were included in the study, it was possible to analyze individual parameters over wide ranges. Molecular methods were used to detect genes for thermolabile hemolysin (tlh), thermostable direct hemolysin (tdh), and tdh-related hemolysin (trh) as indicators of V. parahaemolyticus and the hemolysin gene vvhA for V. vulnificus. SST and suspended particulate matter were found to be strong predictors of total and potentially pathogenic V. parahaemolyticus and V. vulnificus. Other predictors included chlorophyll a, salinity, and dissolved organic carbon. For the ecologically unique sites included in the study, SST was confirmed as an effective predictor of annual variation in vibrio abundance, with other parameters explaining a portion of the variation not attributable to SST. 相似文献
103.
Roberta Nunes Horta Vivian Francilia Silva Kahl Merielen da Silva Sarmento Marisa Fernanda Silva Nunes Carem Rejane Maglione Porto Vanessa Moraes de Andrade Alexandre de Barros Falc?o Ferraz Juliana Da Silva 《Genetics and molecular biology》2016,39(1):122-128
Metal ions such as iron can induce DNA damage by inducing reactive oxygen species (ROS) and oxidative stress. Vitamin C is one of the most widely consumed antioxidants worldwide, present in many fruits and vegetables, especially inMalpighia glabra L., popularly known as acerola, native to Brazil. Acerola is considered a functional fruit due to its high antioxidant properties and phenolic contents, and therefore is consumed to prevent diseases or as adjuvant in treatment strategies. Here, the influence of ripe and unripe acerola juices on iron genotoxicity was analyzed in vivo using the comet assay and micronucleus test. The comet assay results showed that acerola juice exerted no genotoxic or antigenotoxic activity. Neither ripe nor unripe acerola juices were mutagenic to animals treated with juices, in micronucleus test. However, when compared to iron group, the pre-treatment with acerola juices exerted antimutagenic activity, decreasing significantly micronucleus mean values in bone marrow. Stage of ripeness did not influence the interaction of acerola compounds with DNA, and both ripe and unripe acerola juices exerted protective effect over DNA damage generated by iron. 相似文献
104.
105.
106.
Victor M. Victor Susana Rovira-Llopis Vanessa Saiz-Alarcon Maria C. Sangüesa Luis Rojo-Bofill Celia Ba?uls Rosa Falcón Raquel Castelló Luis Rojo Milagros Rocha Antonio Hernández-Mijares 《PloS one》2014,9(9)
Context
Anorexia nervosa is a common illness among adolescents and is characterised by oxidative stress.Objective
The effects of anorexia on mitochondrial function and redox state in leukocytes from anorexic subjects were evaluated.Design and setting
A multi-centre, cross-sectional case-control study was performed.Patients
Our study population consisted of 20 anorexic patients and 20 age-matched controls, all of which were Caucasian women.Main outcome measures
Anthropometric and metabolic parameters were evaluated in the study population. To assess whether anorexia nervosa affects mitochondrial function and redox state in leukocytes of anorexic patients, we measured mitochondrial oxygen consumption, membrane potential, reactive oxygen species production, glutathione levels, mitochondrial mass, and complex I and III activity in polymorphonuclear cells.Results
Mitochondrial function was impaired in the leukocytes of the anorexic patients. This was evident in a decrease in mitochondrial O2 consumption (P<0.05), mitochondrial membrane potential (P<0.01) and GSH levels (P<0.05), and an increase in ROS production (P<0.05) with respect to control subjects. Furthermore, a reduction of mitochondrial mass was detected in leukocytes of the anorexic patients (P<0.05), while the activity of mitochondrial complex I (P<0.001), but not that of complex III, was found to be inhibited in the same population.Conclusions
Oxidative stress is produced in the leukocytes of anorexic patients and is closely related to mitochondrial dysfunction. Our results lead us to propose that the oxidative stress that occurs in anorexia takes place at mitochondrial complex I. Future research concerning mitochondrial dysfunction and oxidative stress should aim to determine the physiological mechanism involved in this effect and the physiological impact of anorexia. 相似文献107.
A recessive Salmonella Typhimurium susceptibility locus (immunity to Typhimurium (Ity3) was reported previously on distal mouse chromosome 1 using a cross between C57BL/6J and wild-derived MOLF/Ei mice. This quantitative trait locus is located in a genomic region spanning 84 Mb, rich in candidate genes for which a role in host resistance to Salmonella infection is either known or can be envisioned. In this study, we report the evaluation of neutrophil cytosolic factor 2 (Ncf2) as a candidate Salmonella susceptibility gene for Ity3. Ncf2 encodes p67phox, a subunit of the multiprotein enzyme complex NADPH oxidase, known to be responsible for the generation of superoxides. Congenic mice carrying the Ity3 region from MOLF/Ei, B6.MOLF-Ity/Ity3 were more susceptible to infection compared with control mice heterozygous at Ity3, B6.MOLF-Ity/Ity3(MOLF/B6), confirming the existence of a recessive Salmonella susceptibility locus on distal chromosome 1. Spleen Ncf2 expression levels were lower in infected congenic mice homozygous for the MOLF/Ei allele at Ity3 compared with mice heterozygous at Ity3. C57BL/6J and MOLF/Ei Ncf2 sequence comparisons revealed one nonconservative amino acid change (R394Q) in the functional and highly conserved Phox and Bem1 domain of the protein. Functional analysis revealed that the MOLF/Ei allele had reduced PMA- and Salmonella-induced superoxide induction as compared with their wild-type counterparts ex vivo. The R394Q substitution seems to occur on an amino acid involved in electrostatic interactions with p40phox, crucial in its activation. Moreover, a human mutation in the corresponding R395W, resulting in chronic granulatomous disease, is known to lead to reduced superoxide levels. These results support the candidacy of Ncf2 as the gene underlying Ity3. 相似文献
108.
Vanessa Castelli Francesco Melani Claudio Ferri Michele d'Angelo Mariano Catanesi Davide Grassi Elisabetta Benedetti Antonio Giordano Annamaria Cimini Giovambattista Desideri 《Journal of cellular biochemistry》2020,121(12):4862-4869
Oxidative stress is considered the common effector of the cascade of degenerative events in many neurological conditions. Thus, in this paper we tested different nutraceuticals in H2O2 in vitro model to understand if could represent an adjuvant treatment for neurological diseases. In this study, nutraceuticals bacopa, lycopene, astaxanthin, and vitamin B12 were used alone or in combination in human neuronal differentiated SH-SY5Y cells upon hydrogen peroxide-induced injury and neuroprotective, neuronal death pathways were analyzed. The nutraceuticals analyzed were able to protect H2O2 cytotoxic effects, through increasing cell viability and proteins involved in neuroprotection pathways and restoring proteins involved in cell death pathways. On this basis, it is possible to propose the use of these compounds as dietary supplement for the prevention or as adjuvant to the only symptomatic treatments so far available for neurodegenerative diseases. 相似文献
109.
Hui Yang Philippe Ciais Maurizio Santoro Yuanyuan Huang Wei Li Yilong Wang Ana Bastos Daniel Goll Almut Arneth Peter Anthoni Vivek K. Arora Pierre Friedlingstein Vanessa Harverd Emilie Joetzjer Markus Kautz Sebastian Lienert Julia E. M. S. Nabel Michael O'Sullivan Stephen Sitch Nicolas Vuichard Andy Wiltshire Dan Zhu 《Global Change Biology》2020,26(7):3997-4012
Gaps in our current understanding and quantification of biomass carbon stocks, particularly in tropics, lead to large uncertainty in future projections of the terrestrial carbon balance. We use the recently published GlobBiomass data set of forest above‐ground biomass (AGB) density for the year 2010, obtained from multiple remote sensing and in situ observations at 100 m spatial resolution to evaluate AGB estimated by nine dynamic global vegetation models (DGVMs). The global total forest AGB of the nine DGVMs is 365 ± 66 Pg C, the spread corresponding to the standard deviation between models, compared to 275 Pg C with an uncertainty of ~13.5% from GlobBiomass. Model‐data discrepancy in total forest AGB can be attributed to their discrepancies in the AGB density and/or forest area. While DGVMs represent the global spatial gradients of AGB density reasonably well, they only have modest ability to reproduce the regional spatial gradients of AGB density at scales below 1000 km. The 95th percentile of AGB density (AGB95) in tropics can be considered as the potential maximum of AGB density which can be reached for a given annual precipitation. GlobBiomass data show local deficits of AGB density compared to the AGB95, particularly in transitional and/or wet regions in tropics. We hypothesize that local human disturbances cause more AGB density deficits from GlobBiomass than from DGVMs, which rarely represent human disturbances. We then analyse empirical relationships between AGB density deficits and forest cover changes, population density, burned areas and livestock density. Regression analysis indicated that more than 40% of the spatial variance of AGB density deficits in South America and Africa can be explained; in Southeast Asia, these factors explain only ~25%. This result suggests TRENDY v6 DGVMs tend to underestimate biomass loss from diverse and widespread anthropogenic disturbances, and as a result overestimate turnover time in AGB. 相似文献
110.
Vanessa E. Jahnke Odile Sabido Aurélia Defour Josiane Castells Etienne Lefai Damien Roussel Damien Freyssenet 《PloS one》2010,5(1)