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Enea Spada Giovanni Rezza Anna Rosa Garbuglia Flavia Lucia Lombardo Ornella Zuccaro Francesca Menniti Ippolito Elisabetta Cupellaro Stefania Capone Maria Rosaria Capobianchi Alfredo Nicosia Riccardo Cortese Antonella Folgori Alfonso Mele The Collaborative Study Group 《Journal of urban health》2018,95(1):99-110
So far, only three small outdated studies have investigated hepatitis C virus (HCV) incidence and risk factors among illicit drug users (DUs) in Italy. Thus, during 2007–2010, we conducted a prospective cohort study among DUs attending 17 Italian rehabilitation centers serving urban areas. Two hundred eighty-four HCV-uninfected DUs were prospectively followed by interview and anti-HCV antibody and RNA testing every 6 months. Incidence was calculated using the person-years method. Infection predictors were assessed by time-dependent Cox analysis. Participants were mostly male (83.4%), under opioid substitution therapy (OST) (78.9%), non-injecting DUs (67.9%), and with a mean age of 30.8. Ninety-one of 224 DUs initially under OST interrupted treatment during the follow-up. Overall HCV incidence was 5.83/100 person-years at risk (PYAR) [95% confidence intervals (CI), 3.63–9.38]. The incidence did not significantly differ according the participants’ sociodemographic characteristics or the degree of urbanization of the towns involved in the study. The incidence was higher for DUs under than for those not under OST (6.23 vs 4.50/100 PYAR; p = 0.681). Incidence was also higher for those with than for those without OST interruption (7.17 vs 5.04/100 PYAR; p = 0.55). However, all these differences were non-significant. At last follow-up visit, a significant decrease in frequency of sharing equipment for preparation/using drugs (by injection or not) was observed by analyzing either the whole cohort or DUs under OST only. Anti-HCV seroconversion resulted independently associated with sharing drug preparation/use equipment, backloading, having a HCV-positive sexual partner, or household and (marginally) intravenous injection. In this study, HCV incidence was non-negligible and OST seemed to lack effectiveness in reducing it. In Italy, implementation of combined harm reduction interventions and antiviral treatment of chronically infected DUs would be needed. 相似文献
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Palmerini T Coller BS Cervi V Tomasi L Marzocchi A Marrozzini C Leone O Piccioli M Branzi A 《Journal of the American College of Cardiology》2004,44(8):1570-1577
OBJECTIVES: This study evaluated the role of circulating tissue factor (TF) in mediating thrombus formation on stents in an in vitro model of stent perfusion. BACKGROUND: The traditional view of coagulation has recently been challenged by the demonstration that TF is present in circulating blood. The potential contribution of this intravascular pool of TF to thrombus formation on stents is not known. METHODS: Coronary stents were placed in parallel silicone tubes connected to a roller pump that was set to pump blood at a flow rate of 10 ml/min. Stents were then exposed to heparinized blood from healthy volunteers for 120 min. RESULTS: The presence of the stent in the circuit caused a significant increase in monocyte TF expression, but only monocytes with attached platelets stained positive for TF. Thrombi formed on stents and the thrombi stained positive for TF. Pretreatment of blood with a monoclonal antibody against TF (cH36) caused a 56% reduction in (125)I-fibrin(ogen) deposition on stents compared with controls (p = 0.002). Monocyte depletion of blood reduced (125)I-fibrin(ogen) deposition by 45% (p = 0.01) and TF staining in the thrombus by 83% (p = 0.01). Pretreatment of blood with a monoclonal antibody against P-selectin reduced (125)I-fibrin(ogen) deposition by 24% (p = 0.04). Perfusion of stents with leukocyte-reduced platelet-rich plasma (PRP) produced small thrombi and treatment of PRP with cH36 reduced (125)I-fibrin(ogen) deposition by 43% (p = 0.01). CONCLUSIONS: Circulating TF plays a pivotal role in thrombus formation on stents. Monocytes appear to be the main, but not only, source of TF depositing in the thrombus. 相似文献
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Alginate is a natural polysaccharide that has been recently gaining increasing attention as a biomaterial in the field of tissue engineering due to its favourable biocompatibility and gelation properties. Alginate hydrogels are commonly made by ionic crosslinking in the presence of divalent cations. Only a few studies have attempted to prepare alginate hydrogels without the presence of metal cations. Here the formation of metal free alginate hydrogels in the presence of the amino-acid glutamine is investigated. The transition from sol to gel is monitored by rheological measurements in the viscoelastic regime that reveal how the charged or neutral form of glutamine induces deep differences in the gelling ability. In particular, we show that the storage, G′, and loss, G′′, moduli differ significantly by shifting the glutamine zwitterionic equilibrium. Protonated amino acid could induce a shielding effect of the electrostatic repulsion of the alginate chains. Stable gels are obtained in the presence of a larger amount of free organic acid that gives rise to chain crosslink junctions and chain–chain stabilization. This opens up the possibility of preparing metal-free alginate hydrogels based on amino acid equilibria being pH sensitive.Alginate gelling by ionic cross-linking using multivalent ions has been known and exploited for several decades. We focus on the possibility to obtain alginate hydrogels without using metal cation in order to obtain metal-free alginates hydrogels. 相似文献
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Giulia Massini Nicol Capra Raffaele Buganza Anna Nyffenegger Luisa de Sanctis Ornella Guardamagna 《Nutrients》2022,14(7)
Background: Diet is considered the cornerstone of lipid management in hyperlipidemic children but evidence to demonstrate the effects of nutrient benefits on the lipid profile is limited. Aim: The aim of this study is to evaluate the impact of the Mediterranean diet on low-density lipoprotein (LDL-C) and non-high density lipoprotein (HDL-C) decrease in primary hyperlipidemia affected children and in the achievement of therapeutical target levels. Methods: A retrospective cohort study was used, recruiting n = 223 children (10.05 ± 3.26 mean age years) with familial hypercholesterolemia (FH) (n = 61, 27%) and polygenic hypercholesterolemia (PH) (n =162, 73%). Secondary hyperlipidemias were excluded. Based on LDL-C and non-HDL-C decrease, participants were divided into two groups, named the Responder Group and Non-Responder Group. Participants and their families underwent dietary education by an expert nutritionist and were asked to fill in a weekly diary to be delivered at visits. Dietary indications were in line with daily caloric requirement, daily food quality and quantity intakes typical of the Mediterranean diet. These include carbohydrates, extra virgin olive oil, yoghurt and milk derivatives, fish and vegetable proteins, fresh seasonal vegetables and fresh fruits. Nuts or almonds were also recommended. The advice to limit intakes of meat, in particular red meat, and caution against junk food and sugar added food and beverages was provided. At medical visits, carried out at baseline (T0) and 6 months later (T1), children underwent anthropometric measurements and blood collection. Standard kits and methods were applied for lipid analysis. Statistical methods were performed by SAS version 9.4 (SAS Institute, Cary, NC, USA). Signed informed consent was given by parents according to the Declaration of Helsinki and the study was approved by the Local Committee. Results: The Responder Group (n = 156/223, 70%) included 45 FH and 111 PH children, while the Non-Responder Group (n = 67/223, 30%) included 16 FH and 51 PH children. The Responder Group showed total cholesterol (TC), LDL-C and non-HDL-C median percentage decreases of 9.45, 13.51 and 10.90, respectively. These statistically significant changes (p ≤ 0.0001) were similar in the FH and PH subgroups but just PH subjects reached the LDL-C and non-HDL-C target, which fell below 130 mg/dL and 145 mg/dL, respectively. Saturated fatty acids (SFAs) were the main dietary parameter that distinguished between the Responder Group and the Non-Responder Group (p = 0.014). Positive correlations were found at T1 between dietary total lipids, SFAs and cholesterol with serum LDL-C, non-HDL-C and TC variations. These latter serum parameters had an inverse correlation with dietary carbohydrate at T1. Among macronutrients, SFAs were finally demonstrated to be the predictor of serum lipids variation at T1. Conclusions: The dietary intervention with a Mediterranean diet in children with primary hyperlipidemia significantly improves the lipid profile both in FH and PH subgroups and allows target levels of LDL-C and non-HDL-C in PH subjects to be reached. Responsiveness benefits should be primarily attributed to the reduction in SFAs, but changes in dietary lipids, cholesterol and carbohydrate intake may also play a role. In contrast, the Non-Responder Group showed a worsening of lipid profile regarding the unchanged diet. 相似文献
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