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991.
Laura Di Renzo Fabio Galvano Carmine Orlandi Alessia Bianchi Claudia Di Giacomo Luca La Fauci Rosaria Acquaviva Antonino De Lorenzo 《Obesity (Silver Spring, Md.)》2010,18(11):2125-2130
The normal‐weight obese (NWO) syndrome was identified in women whose body weight (BW) and BMI are normal but whose fat mass (FM) is >30%. In these subjects, an early inflammatory status has been demonstrated. The aim was to verify whether oxidative stress occurs in NWO. Sixty age‐matched white Italian women were studied and subdivided as follows: 20 normal‐weight individuals (NW) (BMI <25 kg/m2; FM% <30%); 20 NWO (BMI <25 kg/m2; FM% >30%); 20 preobese‐obese (OB) (BMI >25 kg/m2; FM% >30%). Anthropometric, body composition (by dual‐energy X‐ray absorptiometry) variables, plasma levels of some cytokines, reduced glutathione (GSH), lipid hydroperoxide (LOOH), nitric oxide (NO) metabolites (NO2?/NO3?), antioxidant nonproteic capacity (ANPC) were measured and compared between groups. Glucose and lipid metabolism parameters were assessed. GSH and NO2?/NO3? levels resulted lower in OB and NWO compared to NW (P < 0.01). LOOH levels resulted higher in OB and NWO (P < 0.01). ANPC in NWO was lower than NW but higher with respect to OB (P < 0.01). Correlation analysis revealed strong associations between GSH levels and BW, BMI, FM% (R = ?0.45, at least P < 0.05); waist circumference (W) (R = ?0.33, P < 0.05); FFM% (R = 0.45, P < 0.01); IL‐1α, IL‐6, IL‐10, IL‐15 (R = ?0.39, ?0.33, ?0.36 ?0.34, respectively, P < 0.05); triglycerides (R = ?0.416, P < 0.05). LOOH levels were negatively related to FFM% (R = ?0.413, P < 0.05) and positively to FM%, IL‐15, TNF‐α, insulin, total cholesterol, low‐density lipoprotein cholesterol, and triglycerides (R = 0.408, R = 0.502, R = 0.341, R = 0.412, R = 0.4036, R = 0.405, R = 0.405, respectively, P < 0.05). The study clearly indicates that NWO, besides being in early inflammatory status, are contextually exposed to an oxidative stress related to metabolic abnormalities occurring in obesity. 相似文献
992.
993.
Barbagallo AP Weldon R Tamayev R Zhou D Giliberto L Foreman O D'Adamio L 《PloS one》2010,5(11):e15503
Background
The pathogenesis of Alzheimer''s disease is attributed to misfolding of Amyloid-β (Aβ) peptides. Aβ is generated during amyloidogenic processing of Aβ-precursor protein (APP). Another characteristic of the AD brain is increased phosphorylation of APP amino acid Tyr682. Tyr682 is part of the Y682ENPTY687 motif, a docking site for interaction with cytosolic proteins that regulate APP metabolism and signaling. For example, normal Aβ generation and secretion are dependent upon Tyr682 in vitro. However, physiological functions of Tyr682 are unknown.Methodology/Principal Findings
To this end, we have generated an APP Y682G knock-in (KI) mouse to help dissect the role of APP Tyr682 in vivo. We have analyzed proteolytic products from both the amyloidogenic and non-amyloidogenic processing of APP and measure a profound shift towards non-amyloidogenic processing in APP KI mice. In addition, we demonstrate the essential nature of amino acid Tyr682 for the APP/Fe65 interaction in vivo.Conclusions/Significance
Together, these observations point to an essential role of APP intracellular domain for normal APP processing and function in vivo, and provide rationale for further studies into physiological functions associated with this important phosphorylation site. 相似文献994.
Pasquale Emanuele Scopelliti Antonio Borgonovo Marco Indrieri Luca Giorgetti Gero Bongiorno Roberta Carbone Alessandro Podestà Paolo Milani 《PloS one》2010,5(7)
Background
Protein adsorption is the first of a complex series of events that regulates many phenomena at the nano-bio interface, e.g. cell adhesion and differentiation, in vivo inflammatory responses and protein crystallization. A quantitative understanding of how nanoscale morphology influences protein adsorption is strategic for providing insight into all of these processes, however this understanding has been lacking until now.Methodology/Principal Findings
Here we introduce novel methods for quantitative high-throughput characterization of protein-surface interaction and we apply them in an integrated experimental strategy, to study the adsorption of a panel of proteins on nanostructured surfaces. We show that the increase of nanoscale roughness (from 15 nm to 30 nm) induces a decrease of protein binding affinity (≤90%) and a relevant increase in adsorbed proteins (≤500%) beyond the corresponding increase of specific area. We demonstrate that these effects are caused by protein nucleation on the surface, which is promoted by surface nanoscale pores.Conclusions/Significance
These results show that the adsorption of proteins depends significantly on surface nanostructure and that the relevant morphological parameter regulating the protein adsorption process is the nanometric pore shape. These new findings improve our understanding of the role of nanostructures as a biomaterial design parameter and they have important implications for the general understanding of cell behavior on nanostructured surfaces. 相似文献995.
Maria Cristina Thaller Luciana Migliore Cruz Marquez Washington Tapia Virna Cede?o Gian Maria Rossolini Gabriele Gentile 《PloS one》2010,5(2)
Background
Antibiotic resistance, evolving and spreading among bacterial pathogens, poses a serious threat to human health. Antibiotic use for clinical, veterinary and agricultural practices provides the major selective pressure for emergence and persistence of acquired resistance determinants. However, resistance has also been found in the absence of antibiotic exposure, such as in bacteria from wildlife, raising a question about the mechanisms of emergence and persistence of resistant strains under similar conditions, and the implications for resistance control strategies. Since previous studies yielded some contrasting results, possibly due to differences in the ecological landscapes of the studied wildlife, we further investigated this issue in wildlife from a remote setting of the Galapagos archipelago.Methodology/Principal Findings
Screening for acquired antibiotic resistance was carried out in commensal enterobacteria from Conolophus pallidus, the terrestrial iguana of Isla Santa Fe, where: i) the abiotic conditions ensure to microbes good survival possibilities in the environment; ii) the animal density and their habits favour microbial circulation between individuals; and iii) there is no history of antibiotic exposure and the impact of humans and introduced animal species is minimal except for restricted areas. Results revealed that acquired antibiotic resistance traits were exceedingly rare among bacteria, occurring only as non-dominant strains from an area of minor human impact.Conclusions/Significance
Where both the exposure to antibiotics and the anthropic pressure are minimal, acquired antibiotic resistance traits are not normally found in bacteria from wildlife, even if the ecological landscape is highly favourable to bacterial circulation among animals. Monitoring antibiotic resistance in wildlife from remote areas could also be a useful tool to evaluate the impact of anthropic pressure. 相似文献996.
Elisa Danese Martina Montagnana Gian Luca Salvagno Matteo Gelati Denise Peserico Laura Pighi Simone de Nitto Brandon M. Henry Stefano Porru Giuseppe Lippi 《Journal of Medical Biochemistry》2021,40(4):335
BackgroundSince universal vaccinations represents the most effective strategy to mitigate coronavirus disease 2019 (COVID-19), baseline assessment and post-vaccine monitoring of anti-SARS-CoV-2 neutralizing antibodies are essential to vaccination programs. Therefore, this study aimed to compare data of five commercial anti-SARS-CoV2 immunoassays after administration of an mRNA vaccine.MethodsVenous blood was collected from three healthcare workers, receiving a double (30 g) dose of BNT162b2 mRNA Covid-19 vaccine (Comirnaty, Pfizer), on the day of the first vaccine dose and then at fixed intervals for the following 2 months. Anti-SARS-CoV-2 neutralizing antibody response was assayed with Roche Total Ig anti-RBD (receptor binding domain), DiaSorin TrimericS IgG (spike trimer), Beckman Coulter IgG anti-RBD, SNIBE IgG anti-RBD and Technogenetics IgG anti-N/S1.ResultsA total number of 45 samples were drawn at the end of the 2-month study period. The Spearman''s correlations of absolute anti-SARS-CoV-2 antibodies were always excellent (all p<0.001), comprised between 0.967-0.994. Satisfactory results were also observed when absolute antiSARS-CoV-2 antibodies values of the five methods were compared with the mean consensus value, with correlations always higher than 0.979 (all p<0.001). The agreement of anti-SARS-CoV-2 antibodies positivity versus the consensus median positivity ranged between 0.764 and 1.000 (always p<0.001), but become always >0.900 after readjustment of one assay cutoff.ConclusionsAll the immunoassays evaluated in this study appear suitable for monitoring anti-SARS-CoV-2 neutralizing antibodies response in subjects undergoing mRNA COVID-19 vaccination. 相似文献
997.
Delle Monache G Volpe AR Delle Monache F Vitali A Botta B Espinal R De Bonnevaux SC De Luca C Botta M Corelli F Carmignani M 《Bioorganic & medicinal chemistry letters》1999,9(22):3249-3254
After the isolation of caracasanamide and caracasandiamide, further hypotensive components of Verbesina caracasana were shown to be N3-prenylagmatine, N1-3',4'-dimethoxycinnamoylagmatine, agmatine and galegin (prenylguanidine). The structures were assigned on the basis of the spectral data of both metabolites and products from their alkaline hydrolyses. A pharmacological analysis of these products is also presented. 相似文献
998.
Chloroplast inheritance is a very important information to obtain when cpDNA is used to study phylogeography or reconstruct phylogenies. A procedure used for the analyses of chloroplast inheritance in the sea daffodil (Pancratium maritimum) is described using multi-facet approach (artificial cross, germination and end-point PCR amplification). 相似文献
999.
Legacy effects and memory loss: how contingencies moderate the response of rocky intertidal biofilms to present and past extreme events
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Understanding how historical processes modulate the response of ecosystems to perturbations is becoming increasingly important. In contrast to the growing interest in projecting biodiversity and ecosystem functioning under future climate scenarios, how legacy effects originating from historical conditions drive change in ecosystems remains largely unexplored. Using experiments in combination with stochastic antecedent modelling, we evaluated how extreme warming, sediment deposition and grazing events modulated the ecological memory of rocky intertidal epilithic microphytobenthos (EMPB). We found memory effects in the non‐clustered scenario of disturbance (60 days apart), where EMPB biomass fluctuated in time, but not under clustered disturbances (15 days apart), where EMPB biomass was consistently low. A massive grazing event impacted on EMPB biomass in a second run of the experiment, also muting ecological memory. Our results provide empirical support to the theoretical expectation that stochastic fluctuations promote ecological memory, but also show that contingencies may lead to memory loss. 相似文献
1000.
Marina Lozano Almudena Estalrrich Luca Bondioli Ivana Fiore José‐Maria Bermúdez de Castro Juan Luis Arsuaga Eudald Carbonell Antonio Rosas David W. Frayer 《Evolutionary anthropology》2017,26(6):313-324
Fossil hominids often processed material held between their upper and lower teeth. Pulling with one hand and cutting with the other, they occasionally left impact cut marks on the lip (labial) surface of their incisors and canines. From these actions, it possible to determine the dominant hand used. The frequency of these oblique striations in an array of fossil hominins documents the typically modern pattern of 9 right‐ to 1 left‐hander. This ratio among living Homo sapiens differs from that among chimpanzees and bonobos and more distant primate relatives. Together, all studies of living people affirm that dominant right‐handedness is a uniquely modern human trait. The same pattern extends deep into our past. Thus far, the majority of inferred right‐handed fossils come from Europe, but a single maxilla from a Homo habilis, OH‐65, shows a predominance of right oblique scratches, thus extending right‐handedness into the early Pleistocene of Africa. Other studies show right‐handedness in more recent African, Chinese, and Levantine fossils, but the sample compiled for non‐European fossil specimens remains small. Fossil specimens from Sima del los Huesos and a variety of European Neandertal sites are predominately right‐handed. We argue the 9:1 handedness ratio in Neandertals and the earlier inhabitants of Europe constitutes evidence for a modern pattern of handedness well before the appearance of modern Homo sapiens. 相似文献