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1.
Materials (Basel) ; 16(15)2023 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-37570140

RESUMO

With a view to achieving sustainable development and a circular economy, this work focused on the possibility to valorize a secondary waste stream of recycled carbon fiber (rCF) to produce a 3D printing usable material with a PA6,6 polymer matrix. The reinforcing fibers implemented in the research are the result of a double-recovery action: starting with pyrolysis, long fibers are obtained, which are used to produce non-woven fabrics, and subsequently, fiber agglomerate wastes obtained from this last process are ground in a ball mill. The effect of different amounts of reinforcement at 5% and 10% by weight on the mechanical properties of 3D-printed thermoplastic composites was investigated. Although the recycled fraction was successfully integrated in the production of filaments for 3D printing and therefore in the production of specimens via the fused deposition modeling technique, the results showed that fibers did not improve the mechanical properties as expected, due to an unsuitable average size distribution and the presence of a predominant dusty fraction ascribed to the non-optimized ball milling process. PA6,6 + 10 wt.% rCF composites exhibited a tensile strength of 59.53 MPa and a tensile modulus of 2.24 GPa, which correspond to an improvement in mechanical behavior of 5% and 21% compared to the neat PA6,6 specimens, respectively. The printed composite specimens loaded with the lowest content of rCF provided the greatest improvement in strength (+9% over the neat sample). Next, a prediction of the "optimum" critical length of carbon fibers was proposed that could be used for future optimization of recycled fiber processing.

2.
Biomedicines ; 11(3)2023 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-36979951

RESUMO

The aim of this study was to evaluate the relationship between anaemia and biomarkers of central/peripheral congestion in heart failure (HF) and the impact on mortality. We retrospectively evaluated 434 acute/chronic HF (AHF/CHF) patients. Anaemia was defined as haemoglobin levels <12 g/dL (women) or <13 g/dL (men). The brain natriuretic peptide (BNP) and hydration index (HI) were measured. The endpoint of the study was all-cause mortality. Anaemia occurred in 59% of patients with AHF and in 35% with CHF (p < 0.001) and showed a significant correlation with the NYHA functional class and renal function. BNP and HI were significantly higher in patients with anaemia than in those without anaemia. Independent predictors of anaemia included BNP, estimated creatinine clearance (eCrCL), and HI. The all-cause mortality rate was 21%, which was significantly higher in patients with anaemia than in those without anaemia (30% vs. 14%, p < 0.001; hazard ratio: 2.6). At multivariate Cox regression analysis, BNP, eCrCL, and HI were independent predictors for mortality (Hazard ratios: 1.0002, 0.97, and 1.05, respectively), while anaemia was not. Anaemia correlates with HF status, functional class, renal function, BNP, and HI. Anaemia was not an independent predictor for mortality, acting as a disease severity marker in congestive patients rather than as a predictor of death.

3.
J Cardiovasc Dev Dis ; 9(3)2022 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-35323615

RESUMO

The impact of sex on the assessment of congestion in acute heart failure (AHF) is still a matter of debate. The objective of this analysis was to evaluate sex differences in the evaluation of congestion at admission in patients hospitalized for AHF. We consecutively enrolled 494 AHF patients (252 female). Clinical congestion assessment, B-type natriuretic peptide levels analysis, blood urea nitrogen to creatinine ratio (BUN/Cr), plasma volume status estimate (by means of Duarte or Kaplam-Hakim PVS), and hydration status evaluation through bioimpedance analysis were performed. There was no difference in medications between men and women. Women were older (79 ± 9 yrs vs. 77 ± 10 yrs, p = 0.005), and had higher left ventricular ejection fraction (45 ± 11% vs. 38 ± 11%, p < 0.001), and lower creatinine clearance (42 ± 25 mL/min vs. 47 ± 26 mL/min, p = 0.04). The prevalence of peripheral oedema, orthopnoea, and jugular venous distention were not significantly different between women and men. BUN/Cr (27 ± 9 vs. 23 ± 13, p = 0.04) and plasma volume were higher in women than men (Duarte PVS: 6.0 ± 1.5 dL/g vs. 5.1 ± 1.5 dL/g, p < 0.001; Kaplam−Hakim PVS: 7.9 ± 13% vs. −7.3 ± 12%, p < 0.001). At multivariate logistic regression analysis, female sex was independently associated with BUN/Cr and PVS. Female sex was independently associated with subclinical biomarkers of congestion such as BUN/Cr and PVS in patients with AHF. A sex-guided approach to the correct evaluation of patients with AHF might become the cornerstone for the correct management of these patients.

4.
G Ital Cardiol (Rome) ; 22(7): 579-581, 2021 Jul.
Artigo em Italiano | MEDLINE | ID: mdl-34175914

RESUMO

Mechanisms leading to mitral regurgitation can be multiple and have different etiologies. We present the case of severe mitral insufficiency due to posterior papillary muscle rupture in a young man, with exertional dyspnea, but permanently asymptomatic for chest pain and without clinical and laboratory signs of myocardial ischemia at the time of our evaluation.


Assuntos
Insuficiência da Valva Mitral , Isquemia Miocárdica , Humanos , Masculino , Valva Mitral/diagnóstico por imagem , Valva Mitral/cirurgia , Insuficiência da Valva Mitral/diagnóstico por imagem , Insuficiência da Valva Mitral/etiologia , Insuficiência da Valva Mitral/cirurgia , Isquemia Miocárdica/etiologia , Músculos Papilares/diagnóstico por imagem
5.
Eur J Clin Invest ; 45(10): 1098-105, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26255786

RESUMO

BACKGROUND: Tissue Doppler imaging (TDI) may be useful in identifying subjects at higher risk among patients with chronic heart failure (CHF). The clinical role of newly developed TDI parameters, however, still needs to be documented. METHODS: A total of 287 consecutive patients with CHF enrolled in the Daunia Heart Failure Registry underwent echocardiography assessment and were followed prospectively for a median 255 (204-316) days. Conventional echocardiography and TDI parameters were calculated. We also quantified by TDI a combined index (EAS index) of diastolic and systolic performance E'/(A'xS') and assessed its possible additional prognostic role in combination with 'traditional' parameters such as left ventricular ejection fraction (LVEF) and myocardial performance index (MPI). RESULTS: Subjects readmitted for worsening HF were characterized by higher levels of EAS index (median 0·14 (95% C.I. 0·12-0·21) vs. 0·11 (0·10-0·12, P < 0·05)). Increased rates of rehospitalization were found in subjects with EAS index >median (0·115) (21% vs. 10%, P < 0·05); higher EAS index values predicted the incidence of readmissions for worsening HF during follow-up, even at multivariable analysis. The assessment of EAS index in addition to LVEF and MPI showed an adjunctive prognostic value (log-rank P < 0·001 and P < 0·05, respectively). CONCLUSIONS: EAS index assessed by TDI may be helpful in predicting the risk of rehospitalizations in subjects with CHF. EAS index may represent an independent adjunctive tool for the risk stratification of patients with CHF in addition to 'traditional' tools such as LVEF or MPI.


Assuntos
Insuficiência Cardíaca/mortalidade , Hospitalização/estatística & dados numéricos , Idoso , Doença Crônica , Diástole/fisiologia , Ecocardiografia , Feminino , Insuficiência Cardíaca/fisiopatologia , Humanos , Incidência , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Medição de Risco/métodos , Sístole/fisiologia , Disfunção Ventricular Esquerda/mortalidade , Disfunção Ventricular Esquerda/fisiopatologia
6.
Curr Vasc Pharmacol ; 12(6): 873-84, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25440594

RESUMO

Clinical trials demonstrated that statin therapy is associated with a significant reduction in cardiovascular morbidity and mortality when used for either primary or secondary prevention of cardiovascular events. Several studies have shown that statins, having an important effect in the prevention of acute coronary syndromes, are also able to prevent heart failure (HF) in patients with coronary artery disease. This review summarizes the experimental and clinical evidence regarding the role of statins in the management of HF.


Assuntos
Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/tratamento farmacológico , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Animais , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/tratamento farmacológico , Doença da Artéria Coronariana/epidemiologia , Insuficiência Cardíaca/epidemiologia , Humanos , Resultado do Tratamento
7.
Curr Vasc Pharmacol ; 2012 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-23016898

RESUMO

Clinical trials demonstrated that statin therapy is associated with a significant reduction in cardiovascular morbidity and mortality when used for either primary or secondary prevention of cardiovascular events. Several studies have shown that statins, having an important effect in the prevention of acute coronary syndromes, are also able to prevent heart failure (HF) in patients with coronary artery disease. This review summarizes the experimental and clinical evidence regarding the role of statins in the management of HF.

8.
Cardiovasc Hematol Agents Med Chem ; 10(4): 352-61, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22721440

RESUMO

Inflammation is essential for atherogenesis, and many inflammatory markers have been analyzed for their association with short- and long-term outcome in patients with manifestations of coronary artery disease. C-reactive protein (CRP) plasma levels increase in patients with acute coronary syndrome (ACS). CPR is an important prognostic marker in ACS. Although CRP will remain over time a useful marker, the role and implications of increased plasma concentrations of other acute phase proteins (APPs), such as alpha-1-antitrypsin (A1AT), alpha-1 glycoprotein (A1GP), haptoglobin (HG), ceruloplasmin (CP), and C3c and C4 complement fraction, in patients with ACS are still not completely defined. Controversy is the role of statins and other drugs on inflammatory markers. This review summarizes the experimental and clinical evidence regarding the role, and the biological and clinical significance of these APPs in ACS. Furthermore, biological and clinical significance of Pentraxin 3 (PTX3), a member of the pentraxin superfamily, are discussesed.


Assuntos
Síndrome Coronariana Aguda/imunologia , Proteínas de Fase Aguda/imunologia , Inflamação/imunologia , Síndrome Coronariana Aguda/sangue , Humanos , Lactente , Inflamação/sangue
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