479 research outputs found

    Kinetics of bond formation in crosslinked gelatin gels

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    In chemical crosslinking of gelatin solutions, two different time scales affect the kinetics of the gel formation in the experiments. We complement the experimental study with Monte Carlo numerical simulations of a lattice model. This approach shows that the two characteristic time scales are related to the formation of single bonds crosslinker-chain and of bridges between chains. In particular their ratio turns out to control the kinetics of the gel formation. We discuss the effect of the concentration of chains. Finally our results suggest that, by varying the probability of forming bridges as an independent parameter, one can finely tune the kinetics of the gelation via the ratio of the two characteristic times.Comment: 8 pages, 9 figures, revised versio

    Potentiation of low-dose doxorubicin cytotoxicity by affecting p-glycoprotein through caryophyllane sesquiterpenes in hepg2 cells: an in vitro and in silico study

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    Doxorubicin represents a valuable choice for different cancers, although the severe side effects occurring at the high effective dose limits its clinical use. In the present study, potential strategies to potentiate low-dose doxorubicin efficacy, including a metronomic schedule, characterized by a short and repeated exposure to the anticancer drug, and the combination with the natural chemosensitizing sesquiterpenes β-caryophyllene and β-caryophyllene oxide, were assessed in human hepatoma HepG2 cells. The involvement of P-glycoprotein (P-gp) in the HepG2- chemosensitization to doxorubicin was evaluated. Also, the direct interaction of caryophyllene sesquiterpenes with P-gp was characterized by molecular docking and dynamic simulation studies. A metronomic schedule allowed us to enhance the low-dose doxorubicin cytotoxicity and the combination with caryophyllane sesquiterpenes further potentiated this effect. Also, an increased intracellular accumulation of doxorubicin and rhodamine 123 induced by caryophyllane sesquiterpenes was found, thus suggesting their interference with P-gp function. A lowered expression of P-gp induced by the combinations, with respect to doxorubicin alone, was observed too. Docking studies found that the binding site of caryophyllane sesquiterpene was next to the ATP binding domain of P-gp and that β-caryophyllene possessed the stronger binding affinity and higher inhibition potential calculated by MM-PBSA. Present findings strengthen our hypothesis about the potential chemosensitizing power of caryophyllane sesquiterpenes and suggest that combining a chemosensitizer and a metronomic schedule can represent a suitable strategy to overcome drawbacks of doxorubicin chemotherapy while exploiting its powerful activity

    U.V.A.C. MONITORING OF HEAVY METALS IN CONTROLLED MILK AND ITS PRODUCTS IN TURIN DURING 2007

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    The contamination of food by chemical is a worldwide public health concern and is a leading cause of trade problems internationally. Contamination may occur through environmental pollution of air, water and soil, such as heavy metals (As, Cd, Cr, Fe, Hg, Pb), PCB and dioxins, or through the intentional use of various pesticides and other agrochemicals. The AA controlled, during 2007, 26 samples of milk, 2 samples of dessert and 32 samples of cheese coming from UE to the area of the City of Turin. The collected demonstrate that the environmental situation is under control and the milk, dessert and cheese fully satisfy this health requisite

    The reduction of the metabolyc syndrome in Navarra-Spain (RESMENA-S) study; a multidisciplinary strategy based on chrononutrition and nutritional education, together with dietetic and psychological control

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    Introduction: The high prevalence of metabolic syndrome (MS) in Spain requires additional efforts for prevention and treatment. Objective: The study RESMENA-S aims to improve clinical criteria and biomarkers associated with MS though an integral therapy approach. Methods: The study is a randomized prospective parallel design in which is expected to participate a total of 100 individuals. The RESMENA-S group (n = 50) is a personalized weight loss (30% energy restriction) diet, with a macronutrient distribution (carbohydrate / fat / protein) of 40/30/30, high meal frequency (7 / day), low glycemic index/load and high antioxidant capacity as well as a high adherence to the Mediterranean diet. The control group (n = 50) is assigned to a diet with the same energy restriction and based on the American Heart Association pattern. Both experimental groups are under dietary and psychological control during 8 weeks. Likewise, for an additional period of 16 weeks of self-control, is expected that volunteers will follow the same pattern but with no dietary advice. Results: Anthropometrical data and body composition determinations as well as blood and urine samples are being collected at the beginning and end of each phase. This project is registered at www.clinicaltrials.gov with the number NCT01087086 and count with the Research Ethics Committee of the University of Navarra approval (065/2009). Conclusions: Intervention trials to promote the adoption of dietary patterns and healthy lifestyle are of great importance to identify the outcomes and nutritional mechanisms that might explain the link between obesity, metabolic syndrome and associated complications

    Renal function impairment predicts mortality in patients with chronic heart failure treated with resynchronization therapy

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    Background: The use of cardiac resynchronization therapy (CRT) and implantable cardioverter-defibrillator (ICD) for advanced heart failure (HF) is increasing. Renal dysfunction is a common condition in HF which is associated with a worse survival. The study aims at identifying in patients with advanced HF treated with CRT the effect of baseline glomerular filtration rate (GFR), GFR improvement and left ventricular ejection fraction (LVEF) change, after 6-months of CRT implant, on survival. Methods: The study population consisted of 375 advanced HF patients who received a CRT between 1999 and 2009, of these 277 received also an ICD implant. Clinical characteristics (New York Heart Association [NYHA] functional class, ischemic vs. non-ischemic etiology, atrial fibrillation, diabetes, hypertension, LVEF, QRS duration and GFR were recorded. The use of common used drugs was evaluated. Cox proportional hazards analysis was calculated in order to evaluate variables associated to mortality. Results: During a median follow-up of 43.0 months, 93 (24.8%) patients died. Patients deceased during the study had at baseline higher NYHA class and lower LVEF and GFR. In Cox regression analysis, GFR predicts long-term mortality (hazard ratio [HR] 0.983; 95% confidence interval [CI] 0.969\u20130.998; p = 0.023) independently from the effect of others covariates. In addition, a positive GFR improvement 6 months after CRT implant is significantly associated with a lower hazard of mortality (for each 10 mL/min of GFR improvement HR 0.86; 95% CI 0.75\u20130.99; p = 0.038). Conclusions: GFR is a significant predictor of mortality in advanced HF patients who received CRT. A GFR improvement 6 months after CRT implant is significantly associated with a lower hazard of mortality

    HEAVY METALS CONTAMINATION IN FISH OF THE LIGURIAN SEA

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    Aim of this investigation was to evaluate heavy metals contamination (mercury, cadmium and lead) in fish and shellfish from Ligurian Sea. 58 muscle samples (45 fish and 13 shellfish) were collected and analyzed. 20 samples exceeded the maximum residue limits (MRLs) set by regulation for mercury (16 fish and 4 shellfish samples), while only one fish sample was not consistent with the MRL for lead. Therefore, 35,8% of Ligurian fishing turned out to be not adequate and potentially harmful for consumers. In order to estimate the real risk for human health it is necessary to enforce this study, correlating the results with fish species and with the effective fish consumption

    Regulatory noncoding and predicted pathogenic coding variants of ccr5 predispose to severe covid-19

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    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

    Hematopoietic progenitor cell liabilities and alarmins S100A8/A9-related inflammaging associate with frailty and predict poor cardiovascular outcomes in older adults

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    Frailty affects the physical, cognitive, and social domains exposing older adults to an increased risk of cardiovascular disease and death. The mechanisms linking frailty and cardiovascular outcomes are mostly unknown. Here, we studied the association of abundance (flow cytometry) and gene expression profile (RNAseq) of stem/progenitor cells (HSPCs) and molecular markers of inflammaging (ELISA) with the cardiorespiratory phenotype and prospective adverse events of individuals classified according to levels of frailty. Two cohorts of older adults were enrolled in the study. In a cohort of pre‐frail 35 individuals (average age: 75 years), a physical frailty score above the median identified subjects with initial alterations in cardiorespiratory function. RNA sequencing revealed S100A8/A9 upregulation in HSPCs from the bone marrow (>10‐fold) and peripheral blood (>200‐fold) of individuals with greater physical frailty. Moreover higher frailty was associated with increased alarmins S100A8/A9 and inflammatory cytokines in peripheral blood. We then studied a cohort of 104 more frail individuals (average age: 81 years) with multidomain health deficits. Reduced levels of circulating HSPCs and increased S100A8/A9 concentrations were independently associated with the frailty index. Remarkably, low HSPCs and high S100A8/A9 simultaneously predicted major adverse cardiovascular events at 1‐year follow‐up after adjustment for age and frailty index. In conclusion, inflammaging characterized by alarmin and pro‐inflammatory cytokines in pre‐frail individuals is mirrored by the pauperization of HSPCs in frail older people with comorbidities. S100A8/A9 is upregulated within HSPCs, identifying a phenotype that associates with poor cardiovascular outcomes
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