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1.
ChemSusChem ; : e202401185, 2024 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-39325923

RESUMO

Fe-Nx-Cs being suitable to replace scarce and overpriced platinum group metals (PGMs) for cathodic oxygen reduction reaction (ORR) are gaining significant importance in the fuel cell arena. Although the typical sacrificial support method (SSM) ensures the superior electrocatalytic activity of derived Fe-Nx-C, removing silica hard templates always remains a great challenge due to the hazardous use of highly toxic and not environmentally friendly hydrofluoric acid. Herein, strategic insight was given to modified SSM by exploiting the in-situ formation of HF, deriving from the decomposition of NH4HF2 and NaF, to dissolve silica templates, thus avoiding the direct use of HF. First, the suitable molar ratio between the etching agent and the silica was analyzed, revealing that NH4HF2 efficiently dissolved silica even in a stoichiometric amount, whereas an excess of NaF was required. However, both etching agents exhibited conformal removal of silica while dispersed active moieties within the highly porous architecture of derived electrocatalysts were left behind. Moreover, NH4HF2-washed counterparts demonstrated relatively higher performance both in acidic and alkaline media. Notably, with NH4HF2-washed Fe-Nx-C electrocatalyst a remarkable onset potential of 970 mV (vs RHE) was achieved with nearly tetra-electronic ORR as the peroxide yield remained less than 10% in the alkaline medium.

3.
J Clin Med ; 12(5)2023 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36902517

RESUMO

Patients with cystic fibrosis often complain of joint manifestations. However, only a few studies have reported the association between cystic fibrosis and juvenile idiopathic arthritis and addressed the therapeutic challenges of these patients. We describe the first paediatric case of a patient affected by cystic fibrosis, Basedow's disease and juvenile idiopathic arthritis who was contemporarily treated with elexacaftor/tezacaftor/ivacaftor (ELX/TEZ/IVA) and anti-tumor necrosis factor α (anti-TNFα). This report seems to reassure regarding the potential side effects of these associations. Moreover, our experience suggests that anti-TNFα is an effective option in CF patients affected by juvenile idiopathic arthritis, and is even safe for children receiving a triple CFTR modulator.

4.
Mar Drugs ; 21(3)2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-36976196

RESUMO

Chitosan is a marine-origin polysaccharide obtained from the deacetylation of chitin, the main component of crustaceans' exoskeleton, and the second most abundant in nature. Although this biopolymer has received limited attention for several decades right after its discovery, since the new millennium chitosan has emerged owing to its physicochemical, structural and biological properties, multifunctionalities and applications in several sectors. This review aims at providing an overview of chitosan properties, chemical functionalization, and the innovative biomaterials obtained thereof. Firstly, the chemical functionalization of chitosan backbone in the amino and hydroxyl groups will be addressed. Then, the review will focus on the bottom-up strategies to process a wide array of chitosan-based biomaterials. In particular, the preparation of chitosan-based hydrogels, organic-inorganic hybrids, layer-by-layer assemblies, (bio)inks and their use in the biomedical field will be covered aiming to elucidate and inspire the community to keep on exploring the unique features and properties imparted by chitosan to develop advanced biomedical devices. Given the wide body of literature that has appeared in past years, this review is far from being exhaustive. Selected works in the last 10 years will be considered.


Assuntos
Quitosana , Animais , Quitosana/química , Materiais Biocompatíveis/química , Quitina/química , Polissacarídeos/química , Crustáceos , Engenharia Tecidual
5.
Polymers (Basel) ; 15(5)2023 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-36904448

RESUMO

Sepiolite clay is a natural filler particularly suitable to be used with polysaccharide matrices (e.g., in starch-based bio-nanocomposites), increasing their attractiveness for a wide range of applications, such as packaging. Herein, the effect of the processing (i.e., starch gelatinization, addition of glycerol as plasticizer, casting to obtain films) and of the sepiolite filler amount on the microstructure of starch-based nanocomposites was investigated by SS-NMR (solid-state nuclear magnetic resonance), XRD (X-ray diffraction) and FTIR (Fourier-transform infrared) spectroscopy. Morphology, transparency and thermal stability were then assessed by SEM (scanning electron microscope), TGA (thermogravimetric analysis) and UV-visible spectroscopy. It was demonstrated that the processing method allowed to disrupt the rigid lattice structure of semicrystalline starch and thus obtain amorphous flexible films, with high transparency and good thermal resistance. Moreover, the microstructure of the bio-nanocomposites was found to intrinsically depend on complex interactions among sepiolite, glycerol and starch chains, which are also supposed to affect the final properties of the starch-sepiolite composite materials.

6.
Langmuir ; 38(50): 15662-15671, 2022 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-36480813

RESUMO

The present study reports on the synthesis of a new alkoxysilane-bearing light-responsive cinnamyl group and its application as a surface functionalization agent for the development of SiO2 nanoparticles (NPs) with photoreversible tails. In detail, cinnamic acid (CINN) was activated with N-hydroxysuccinimide (NHS) to obtain the corresponding NHS-ester (CINN-NHS). Subsequently, the amine group of 3-aminopropyltriethoxysilane (APTES) was acylated with CINN-NHS leading to the generation of a novel organosilane, CINN-APTES, which was then exploited for decorating SiO2 NPs. The covalent bond to the silica surface was confirmed by solid state NMR, whereas thermogravimetric analysis unveiled a functionalization degree much higher compared to that achieved by a conventional double-step post-grafting procedure. In light of these intriguing results, the strategy was successfully extended to naturally occurring sepiolite fibers, widely employed as fillers in technological applications. Finally, a preliminary proof of concept of the photoreversibility of the obtained SiO2@CINN-APTES system has been carried out through UV diffuse reflectance. The overall outcomes prove the consistency and the versatility of the methodological protocol adopted, which appears promising for the design of hybrid NPs to be employed as building blocks for photoresponsive materials with the ability to change their molecular structure and subsequent properties when exposed to different light stimuli.


Assuntos
Nanopartículas Multifuncionais , Nanopartículas , Dióxido de Silício/química , Propilaminas/química , Nanopartículas/química
7.
J Thromb Haemost ; 19(5): 1364-1371, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33880867

RESUMO

BACKGROUND: The ISTH Bleeding Assessment Tool (ISTH-BAT) has been validated for clinical screening of suspected von Willebrand disease (VWD) and for bleeding prediction. Recently it has been validated for subjects with inherited platelet disorders (IPD) (BAT-VAL study). OBJECTIVES: To determine whether the ISTH-BAT bleeding score (BS) predicts subsequent bleeding events requiring treatment in IPD patients. METHODS: Patients with IPD, type 1 VWD (VWD-1) and age- and sex-matched healthy controls enrolled in the BAT-VAL study were prospectively followed-up for 2 years and bleeding episodes requiring treatment were recorded. RESULTS: Of the 1098 subjects initially enrolled, 955 were followed-up and 124 suffered hemorrhages during follow-up, 60% of whom had inherited platelet function disorders (IPFD). Total number of events was significantly higher in IPFD (n = 235) than VWD-1 (n = 52) or inherited thrombocytopenia (IT; n = 20). Events requiring transfusions were 66% in IPFD, 5.7% in VWD-1, and 3% in IT. Baseline BS was significantly higher in IPFD patients with a bleeding event at follow-up than in those without (p < .01) and the percentage of subjects suffering a bleeding event increased proportionally to baseline BS quartile. A significant association between the BS and the chance of suffering severe bleeding was found in the overall, IPFD, and VWD-1 populations. Similar results were obtained for the pediatric population. CONCLUSIONS: Inherited platelet function disorder patients with high BS at enrollment are more likely to suffer from bleeding events requiring treatment at follow-up. Moreover, the higher the baseline BS quartile the greater the incidence of subsequent events, suggesting that independently from diagnosis a high BS is associated with a greater risk of subsequent hemorrhage.


Assuntos
Transtornos Plaquetários , Doenças de von Willebrand , Transtornos Plaquetários/diagnóstico , Transtornos Plaquetários/genética , Criança , Comunicação , Hemorragia/diagnóstico , Humanos , Testes de Função Plaquetária , Doenças de von Willebrand/diagnóstico , Doenças de von Willebrand/genética , Fator de von Willebrand
8.
J Thromb Haemost ; 18(3): 732-739, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31750621

RESUMO

BACKGROUND: Careful assessment of bleeding history is the first step in the evaluation of patients with mild/moderate bleeding disorders, and the use of a bleeding assessment tool (BAT) is strongly encouraged. Although a few studies have assessed the utility of the ISTH-BAT in patients with inherited platelet function disorders (IPFD) none of them was sufficiently large to draw conclusions and/or included appropriate control groups. OBJECTIVES: The aim of the present study was to test the utility of the ISTH-BAT in a large cohort of patients with a well-defined diagnosis of inherited platelets disorder in comparison with two parallel cohorts, one of patients with type-1 von Willebrand disease (VWD-1) and one of healthy controls (HC). PATIENTS/METHODS: We enrolled 1098 subjects, 482 of whom had inherited platelet disorders (196 IPFD and 286 inherited platelet number disorders [IT]) from 17 countries. RESULTS: IPFD patients had significantly higher bleeding score (BS; median 9) than VWD-1 patients (median 5), a higher number of hemorrhagic symptoms (4 versus 3), and higher percentage of patients with clinically relevant symptoms (score > 2). The ISTH-BAT showed excellent discrimination power between IPFD and HC (0.9 < area under the curve [AUC] < 1), moderate (0.7 < AUC < 0.9) between IPFD and VWD-1 and between IPFD and inherited thrombocytopenia (IT), while it was inaccurate (AUC ≤ 0.7) in discriminating IT from HC. CONCLUSIONS: The ISTH-BAT allows to efficiently discriminate IPFD from HC, while it has lower accuracy in distinguishing IPFD from VWD-1. Therefore, the ISTH-BAT appears useful for identifying subjects requiring laboratory evaluation for a suspected IPFD once VWD is preliminarily excluded.


Assuntos
Transtornos Plaquetários , Doenças de von Willebrand , Transtornos Plaquetários/diagnóstico , Transtornos Plaquetários/genética , Comunicação , Hemorragia/diagnóstico , Humanos , Testes de Função Plaquetária , Doenças de von Willebrand/diagnóstico , Doenças de von Willebrand/genética
9.
Haematologica ; 105(7): 1948-1956, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31558677

RESUMO

Major surgery is associated with an increased risk of venous thromboembolism (VTE), thus the application of mechanical or pharmacologic prophylaxis is recommended. The incidence of VTE in patients with inherited platelet disorders (IPD) undergoing surgical procedures is unknown and no information on the current use and safety of thromboprophylaxis, particularly of low-molecular-weight-heparin in these patients is available. Here we explored the approach to thromboprophylaxis and thrombotic outcomes in IPD patients undergoing surgery at VTE-risk participating in the multicenter SPATA study. We evaluated 210 surgical procedures carried out in 155 patients with well-defined forms of IPD (VTE-risk: 31% high, 28.6% intermediate, 25.2% low, 15.2% very low). The use of thromboprophylaxis was low (23.3% of procedures), with higher prevalence in orthopedic and gynecological surgeries, and was related to VTE-risk. The most frequently employed thromboprophylaxis was mechanical and appeared to be effective, as no patients developed thrombosis, including patients belonging to the highest VTE-risk classes. Low-molecular-weight-heparin use was low (10.5%) and it did not influence the incidence of post-surgical bleeding or of antihemorrhagic prohemostatic interventions use. Two thromboembolic events were registered, both occurring after high VTE-risk procedures in patients who did not receive thromboprophylaxis (4.7%). Our findings suggest that VTE incidence is low in patients with IPD undergoing surgery at VTE-risk and that it is predicted by the Caprini score. Mechanical thromboprophylaxis may be of benefit in patients with IPD undergoing invasive procedures at VTE-risk and low-molecular-weight-heparin should be considered for major surgery.


Assuntos
Trombose , Tromboembolia Venosa , Anticoagulantes , Fibrinolíticos/uso terapêutico , Heparina de Baixo Peso Molecular/uso terapêutico , Humanos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle , Trombose/epidemiologia , Trombose/etiologia , Trombose/prevenção & controle , Tromboembolia Venosa/epidemiologia , Tromboembolia Venosa/etiologia , Tromboembolia Venosa/prevenção & controle
10.
World J Clin Cases ; 7(9): 1021-1027, 2019 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-31123674

RESUMO

BACKGROUND: In paediatric patients with complicated nephrotic syndrome (NS), rituximab (RTX) administration can induce persistent IgG hypogammaglobulinemia among subjects showing low basal immunoglobulin G (IgG) levels. AIM: To evaluate the effect of RTX on IgG levels and infections in patients with complicated NS and normal basal IgG levels. METHODS: We consecutively enrolled all patients with complicated NS and normal basal IgG levels undergoing the first RTX infusion from January 2008 to January 2016. Basal IgG levels were dosed after 6 wk of absent proteinuria and with a maximal interval of 3 mo before RTX infusion. The primary outcome was the onset of IgG hypogammaglobulinemia during the follow-up according to the IgG normal values for age [mean ± standard deviation (SD)]. RESULTS: We enrolled 20 patients with mean age at NS diagnosis of 4.2 ± 3.3 years. The mean age at the first RTX infusion was 10.9 ± 3.5 years. Eleven out of twenty patients (55%) developed IgG hypogammaglobulinemia. None of these patients showed severe or recurrent infections. Only one patient suffered from recurrent acute otitis media and underwent substitutive IgG infusion. Three patients undergoing only the two "starting doses" experienced normalization of IgG levels. Using Kaplan-Meier analysis, the cumulative proportion of patients free of IgG hypogammaglobulinemia was 57.8% after the first RTX dose, 51.5% after the third dose, 44.1% after the fourth dose, and 35.5% after the fifth dose. CONCLUSION: RTX can induce IgG hypogammaglobulinemia in patients with pre-RTX IgG normal values. None of the treated patients showed severe infections.

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