Amorphous Elastomeric Ultra-High Molar Mass Polypropylene in High Yield by Half-Titanocene Catalysts.

Propylene polymerizations with different ketimide-modified half-titanocene catalysts, Cp'TiCl(N=CBu) [Cp' = CH (), CMe (), MeSiCH ()], with MAO as a cocatalyst, were investigated. The obtained polymers were studied in detail by determining their microstructure, molar masses, thermal, and mechanical properties. The Cp*-ketimide, (CMe)TiCl(N=CBu) (), exhibited higher catalytic activities than Cp'TiCl(N=CBu) (,), yielding higher molar mass polymers, up to 1400 Kg/mol.

Characteristics of patients with recurrent acute myocardial infarction after MINOCA.

Background: Myocardial infarction (MI) with non-obstructed coronary arteries (MINOCA) is an increasingly recognized condition with challenging management. Some MINOCA patients ultimately experience recurrent acute MI (re-AMI) during follow-up; however, clinical and angiographic factors predisposing to re-AMI are still poorly defined.

Methods: In this retrospective multicenter cohort study we enrolled consecutive patients fulfilling diagnostic criteria of MINOCA according to the IV universal definition of myocardial infarction; characteristics of patients experiencing re-AMI during the follow-up were compared to a group of MINOCA patients without re-AMI.

Worldwide impact of COVID-19 on hospital admissions for non-ST-elevation acute coronary syndromes (NSTACS): a systematic review with meta-analysis of 553 038 cases.

Background: How coronavirus disease 2019 (COVID-19) impacted non-ST-segment elevation acute coronary syndromes (NSTACS) is an object of controversial reports.

Aim: To systematically review studies reporting NSTACS hospitalizations during the COVID-19 pandemic, and analyse whether differences in COVID-19 epidemiology, methodology of report, or public health-related factors could contribute to discrepant findings.

Methods: Comprehensive search (Medline, Embase, Scopus, Web of Science, Cochrane Register), of studies reporting NSTACS hospitalizations during the COVID-19 pandemic compared with a reference period, following Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines.

Myocardial infarction with nonobstructive coronary arteries: from pathophysiology to therapeutic strategies.

Myocardial infarction with nonobstructive coronary arteries (MINOCA) is a heterogeneous group of clinical entities characterized by clinical evidence of acute myocardial infarction (AMI) with normal or near-normal coronary arteries on coronary angiography (stenosis < 50%) and without an over the alternative diagnosis for the acute presentation. Its prevalence ranges from 6% to 11% among all patients with AMI, with a predominance of young, nonwhite females with fewer traditional risks than those with an obstructive coronary artery disease (MI-CAD). MINOCA can be due to either epicardial causes such as rupture or fissuring of unstable nonobstructive atherosclerotic plaque, coronary artery spasm, spontaneous coronary dissection and cardioembolism in-situ or microvascular causes.

Perspectives in noninvasive imaging for chronic coronary syndromes.

Both the latest European guidelines on chronic coronary syndromes and the American guidelines on chest pain have underlined the importance of noninvasive imaging to select patients to be referred to invasive angiography. Nevertheless, although coronary stenosis has long been considered the main determinant of inducible ischemia and symptoms, growing evidence has demonstrated the importance of other underlying mechanisms (e.g.

Clinical outcomes of patients with coronary microvascular dysfunction in absence of obstructive coronary atherosclerosis.

Up to 50% of patients presenting with stable, mainly exercise-induced, chest pain and 10-20% of those admitted to hospital with chest pain suggesting an acute coronary syndrome show normal or near-normal coronary arteries at angiography. Coronary microvascular dysfunction (CMD) is a major cause of symptoms in these patients. However, controversial data exist about their prognosis.

Diagnostic approach for coronary microvascular dysfunction in patients with chest pain and no obstructive coronary artery disease.

A large number of studies has demonstrated that abnormalities of coronary microcirculation may be responsible for both acute and chronic cardiac ischemic syndromes. In clinical practice the microvascular origin of myocardial ischemia and angina is usually considered in patients who are found to have normal or near-normal coronary arteries at angiography. In this article, we review the diagnostic approach to patients with suspected coronary microvascular dysfunction as a cause of ischemic syndromes and also suggest a classification of chronic and acute microvascular coronary ischemic syndrome, including myocardial infarction with normal coronary arteries.

Sex-related differences in ventricular remodeling after myocardial infarction.

The epidemiology, clinical features and outcome of myocardial infarction (MI) display significant differences between men and women. Prominent sex differences have also been suggested in left ventricular (LV) remodeling after MI. Ventricular remodeling refers to a deterioration of LV geometry and function often leading to heart failure (HF) development and an increased risk of adverse cardiovascular events.

Flexible Polyurethane Foams from Epoxidized Vegetable Oils and a Bio-Based Diisocyanate.

Bio-polyols from epoxidized soybean and linseed oils and caprylic acid or 3-phenyl butyric acid were prepared using an environmentally friendly, solvent-free method evaluating the presence of triethylamine as catalyst. Side reactions, leading to a cross-linking structure with high density, were reduced, introducing the catalyst and properly tuning the reaction conditions. A medium functionality value of around 3 along with a hydroxyl number up to around 90 mg KOH/g, narrow polydispersity index, and relatively low molecular mass up to 2400 g/mol were the experimental targets.

Pharmacological therapy for the prevention of cardiovascular events in patients with myocardial infarction with non-obstructed coronary arteries (MINOCA): Insights from a multicentre national registry.

Aims: To assess the effect of pharmacological therapy on long-term prognosis of patients with MINOCA.

Methods And Results: In this retrospective multicentre cohort study involving 9 Hub Hospitals across Italy we enrolled consecutive patients 18 years and older with diagnosis of MINOCA discharged from 1st March 2012 to 31st March 2018. Data on baseline characteristics and pharmacological therapy at discharge (ACEI/ARB, angiotensin-converting enzyme inhibitors/angiotensin receptor antagonists; ASA, acetylsalicylic acid; beta-blockers; CCB, calcium-channel blockers; DAPT, dual anti-platelet therapy; statins), were collected systematically.

Cardiovascular involvement during COVID-19 and clinical implications in elderly patients. A review.

SARS-CoV-2 betacoronavirus is responsible for the Corona Virus Disease 2019 (COVID-19) which has relevant pathogenic implications for the cardiovascular system. Incidence and severity of COVID-19 are higher in the elderly population (65 years and older). This may be due to higher frequency of comorbidities, but increased frailty and immunosenescence linked with aging may also contribute.

Role of endothelial dysfunction in heart failure.

Coronary artery disease is a major underlying etiology for heart failure. The role of coronary microvascular disease, and endothelial dysfunction, in the pathophysiology of heart failure is poorly appreciated. Endothelial dysfunction, induced by oxidative stress, contributes to the development of heart failure.

Association of diabetes and kidney function according to age and systolic function with the incidence of sudden cardiac death and non-sudden cardiac death in myocardial infarction survivors with heart failure.

Aims: An implantable cardioverter-defibrillator (ICD) is recommended for reducing the risk of sudden cardiac death (SCD) in myocardial infarction (MI) patients with a left ventricular ejection fraction (LVEF) ≤ 30%, as well as patients with a LVEF ≤ 35% and heart failure symptoms. Diabetes and/or impaired kidney function may confer additional SCD risk. We assessed the association between these two risk factors with SCD and non-SCD among MI survivors taking account of age and LVEF.

Influence of Co-Catalysts and Polymerization Conditions on Properties of Poly(anhydride--epoxide)s from ROCOP Using Salen Complexes with Different Metals.

Cyclohexene oxide (CHO) and phthalic anhydride (PA) have been reacted in the presence of commercial salen-type complexes with different metals Cr (), Al (), and Mn () in combination with 4-(dimethylamino) pyridine (DMAP), bis-(triphenylphosphorydine) ammonium chloride (PPNCl) and bis-(triphenylphosphoranylidene)ammonium azide (PPNN) as co-catalysts to obtain alternating poly(PA--CHO)s by ring-opening copolymerization (ROCOP). The effect of different reaction conditions (pre-contact between catalyst and co-catalyst, polymerization time) on the productivity, molecular weight and glass transition temperature has been evaluated. By using a 24 h pre-contact, the aliphatic polyesters obtained were characterized by high molecular weight ( > 15 kg/mol) and glass transition temperature () up to 146 °C; the more sustainable metals Al and Mn in the presence of PPNCl give comparable results to Cr.

Effects of Sitagliptin on Lipid Profile in Patients With Type 2 Diabetes Mellitus After 7 Years of Therapy.

The aim of this study was to investigate whether the effects of sitagliptin on lipid profile were maintained even after 7 years of treatment. We treated 591 patients who had not been well controlled by current therapy with the addition of sitagliptin 100 mg/d. Data were compared with those of 612 patients treated with sulfonylureas plus metformin, pioglitazone plus metformin, and pioglitazone plus sulfonylureas.

Microstructure of Copolymers of Norbornene Based on Assignments of C NMR Spectra: Evolution of a Methodology.

An overview of the methodologies to elucidate the microstructure of copolymers of ethylene and cyclic olefins through C Nuclear magnetic resonance (NMR) analysis is given. C NMR spectra of these copolymers are quite complex because of the presence of stereogenic carbons in the monomer unit and of the fact that chemical shifts of these copolymers do not obey straightforward additive rules. We illustrate how it is possible to assign C NMR spectra of cyclic olefin-based copolymers by selecting the proper tools, which include synthesis of copolymers with different comonomer content and by catalysts with different symmetries, the use of one- or two-dimensional NMR techniques.

Ethylene--norbornene Copolymerization Using a Dual Catalyst System in the Presence of a Chain Transfer Agent.

Ethylene--norbornene copolymers were synthesized by a dual catalyst system at three concentrations of norbornene in the feed and variable amounts of ZnEt₂, as a possible chain transfer agent. The dual catalyst system consists of two -metallocenes, isopropyliden(ηcyclopentadienyl)(η⁵-indenyl)zirconium dichloride () and isopropyliden(η⁵-3-methylcyclopentadienyl)(η⁵-fluorenyl)zirconium dichloride (), activated with dimethylanilinium tetrakis(pentafluorophenyl)borate, in presence of TIBA. Values of norbornene content, molecular mass, glass transition temperature, and reactivity ratios and of copolymers prepared in the presence of + are intermediate between those of reference copolymers.

Predictors of poor clinical outcomes in patients with acute myocardial infarction and non-obstructed coronary arteries (MINOCA).

Objective: To assess the characteristics and prognosis of patients with myocardial infarction and non-obstructed coronary arteries (MINOCA).

Methods: MINOCA was defined as acute myocardial infarction (AMI) with angiographic coronary stenosis <50%.Cardiomyopathies and myocarditis were - a priori - excluded from the study.

Propene Polymerization with C₁-Symmetric Fluorenyl-Metallocene Catalysts.

Propene homopolymers have been produced by employing three ₁-symmetric metallocene molecules (, and ), each having -butyl substituent(s) on the p, on the fluorenyl or on both aromatic moieties activated with methylaluminoxane at different polymerization temperatures and monomer concentrations. Polymers' microstructures determined by C NMR spectroscopy suggest that the otherwise dominant alternating mechanism governed by the chain migratory insertion is largely replaced by the competing site epimerization mechanism, as a direct result of the imposing steric bulk of the -butyl substituent on one of the distal positions of the p moiety. This phenomenon is more pronounced with when a second -butyl is present in the same half-space of the molecule making the site epimerization mandatory.

Prognostic value of pulmonary congestion assessed by lung ultrasound imaging during heart failure hospitalisation: A two-centre cohort study.

Pulmonary congestion assessed at discharge by lung ultrasonography predicts poor prognosis in heart failure (HF) patients. We investigated the association of B-lines with indices of hemodynamic congestion [BNP, E/e', pulmonary systolic arterial pressure (PAPs)] in HF patients, and their prognostic value overall and according to concomitant atrial fibrillation (AF), reduced (≤40%) ejection fraction (EF), and timing of quantification during hospitalisation for heart failure (HHF). In 110 HHF patients, B-lines were highly discriminative of BNP >400 pg/ml (AUC ≥ 0.