Roberta Galeazzi

Diagnostic potential of circulating miR-499-5p in elderly patients with acute non ST-elevation myocardial infarction

BACKGROUND Geriatric patients with acute non-ST elevation myocardial infarction (NSTEMI) can frequently present atypical symptoms and non-diagnostic electrocardiogram. The detection of modest cardiac troponin T (cTnT) elevation is challenging for physicians needing to routinely triage these patients. Unfortunately, non-coronary diseases, such as acute heart failure (CHF), may cause cTnT elevation. Circulating microRNAs (miRs) have emerged as biomarkers of MI. However, their diagnostic potential needs to be determined in elderly NSTEMI patients. METHODS 92 NSTEMI patients (82.6 ± 6.9 years old; complicated by CHF in 74% of cases) and 81 patients with acute CHF without AMI (81.3 ± 6.8 years old) were enrolled at presentation. A third group comprised 99 age-matched healthy control subjects (CTR). Plasma levels of miR-1, -21, -133a, -208a, -423-5p and -499-5p were analyzed. RESULTS MiR-1, -21 -133a and -423-5p showed a 3- to 10-fold increase and miR-499-5p exhibited >80-fold increase in acute NSTEMI patient vs. CTR. MiR-499-5p and -21 showed a significantly increased expression in NSTEMI vs. CHF. Interestingly, mir-499-5p was comparable to cTnT in discriminating NSTEMI vs. CTR and CHF patients. Its diagnostic accuracy was higher than conventional and hs-cTnT in differentiating NSTEMI (n=31) vs. acute CHF (n=32) patients with modest cTnT elevation at presentation (miR-499-5p AUC=0.86 vs. cTnT AUC=0.68 and vs. hs-cTnT AUC=0.70). CONCLUSIONS Circulating miR-499-5p is a sensitive biomarker of acute NSTEMI in the elderly, exhibiting a diagnostic accuracy superior to that of cTnT in patients with modest elevation at presentation.

Steady-state and time resolved fluorescence of albumins interacting with N-oleylethanolamine, a component of the endogenous N-acylethanolamines

The functions of N‐acylethanolamines, minor constituents of mammalian cells, are poorly understood. It was suggested that NAEs might have some pharmacological actions and might serve as a cytoprotective response, whether mediated by physical interactions with membranes or enzymes or mediated by activation of cannabinoid receptors. Albumins are identified as the major transport proteins in blood plasma for many compounds including fatty acids, hormones, bilirubin, ions, and many drugs. Moreover, albumin has been used as a model protein in many areas, because of its multifunctional binding properties. Bovine (BSA) and human (HSA) serum albumin are similar in sequence and conformation, but differ for the number of tryptophan residues. This difference can be used to monitor unlike protein domains. Our data suggest that NOEA binds with high affinity to both albumins, modifying their conformational features. In both proteins, NOEA molecules are linked with higher affinity to hydrophobic sites near Trp‐214 in HSA or Trp‐212 in BSA. Moreover, fluorescence data support the hypothesis of the presence of other NOEA binding sites on BSA, likely affecting Trp‐134 environment. The presence of similar binding sites is not measurable on HSA, because it lacks of the second Trp residue. Proteins 2000;40:39–48.

A convenient approach to diastereomerically pure 1,3,4-trisubstituted pyrrolidin-2-ones by intramolecular cyclisation of N-(2-alken-1-yl)amides mediated by Mn(III). An entry to both (R)- and (S)-3-pyrrolidineacetic acid

The oxidative cyclisation of a series of either (S)-N-(2-alken-1-yl)-N-(1-phenyleth-1-yl)-acetoacetamides5a-d and methoxycarbonylacetamides 6a-b, performed by using Mn(OAc)3 · 2H2) and Cu(OAc)2 · H2O in acetic acid, has been examined. The reaction proceeds regioselectively through a 5-exo-mode, leading to 1,3,4-trisubstituted pyrrolidin-2-ones 7a-d,8a-d and 9a-b,10a-b as diastereomeric mixtures in about 2:1 ratio, which are easily separated by silica gel chromatography. The configuration of the pure diastereomers is assigned from 1H NMR data and confirmed by NOE experiments. The observed asymmetric induction has been explained on the basis of molecular mechanics calculations. This cyclisation constitutes a useful tool for the synthesis of biologically active amino acids containing the pyrrolidine ring in both enantiomerically pure forms, such as (R)- and (S)-3-pyrrolidineacetic acid, 1 and 2.

Aged-related increase of high sensitive Troponin T and its implication in acute myocardial infarction diagnosis of elderly patients

High sensitive cardiac Troponin T (hs-cTnT) represents an important tool in acute myocardial infarction (AMI) diagnosis. Even though the hs-cTnT evaluation is relevant for AMI diagnosis in elderly patients characterized by clinical and instrumental atypical presentation, the overall reliability in elderly patients is unknown. We aimed at: (1) defining the hs-cTnT 99th percentile value in an aged healthy reference population and (2) testing hs-cTnT diagnostic accuracy in elderly patients with a suspected AMI. 294 healthy subjects (50-105 years old) and 299 elderly patients (75-96 years old) with suspected AMI at presentation, were enrolled. Conventional cTnT, hs-cTnT, NT-proBNP and creatinine levels were determined in all participants. Our main results are: (1) a significant hs-cTnT age-related increase was observed in an healthy reference population ranging 50-105 years old; (2) hs-cTnT levels showed an age-related multimodal distribution in the healthy reference population: 16 ng/L corresponds to the 99th percentile in subjects ranging 50-75 years old, whereas 70.6 ng/L corresponds to the 99th percentile in subjects ≥75 years old; (3) 86.8 ng/L resulted the hs-cTnT cut-off value with the highest efficiency in AMI diagnosis of geriatric patients. Our data suggest that the hs-cTnT cut-off value must be age-tailored to improve the AMI diagnostic accuracy.

Synthesis of unsaturated β-amino acid derivatives from carbamates of the Baylis–Hillman products

Abstract By treatment with a catalytic amount of DBU in DCM, N-p-toluenesulphonyl carbamates 6a–c , prepared starting from the corresponding Baylis–Hillman adducts, gave (E)-2-(p-toluenesulphonylaminomethyl)propenoates 3a–c , exclusively. On the contrary, changing DABCO for DBU, 2-methylene-3-p-toluenesulfonylamino esters 4a–f were obtained in good yield starting from N-p-toluenesulphonyl carbamates 6a–f . In analogy, N-acyl carbamates 9a–f were treated with DABCO in DCM to give the 2-methylene-3-acylamino esters 5a–f .

Diastereomerically pure pyrrolidin-2-ones by intramolecular Michael reaction. Synthesis of both (S)- and (R)-3-pyrrolidineacetic acid

Abstract By intramolecular conjugate addition of their derived enolates, the amides 5 and 6 gave diastereomeric mixtures of pyrrolidin-2-ones 10,11 and 12,13 , in good yield and 80:20 d.r. After chromatographic separation, the configuration of pure diastereomers was assigned from 1 H NMR data. The usefulness of this intramolecular cyclisation was proven by conversion of either 10 or 12 into pyrrolidin-2-one 14 which through simple steps gave ( S )-3-pyrrolidineacetic acid, 2 . Following the same synthetic scheme, but starting from either 11 or 13 , ( R )-3-pyrrolidineacetic acid 3 was obtained.

From 3-aza-2-oxobicyclo[3.1.0]hexane to enantiopure disubstituted cyclopropane: a convenient approach to cis-2,3-methano-GABA

Abstract Starting from the diastereomerically pure 4-ethenyl pyrrolidin-2-one 5 , through simple steps the mesyl derivative 8 was obtained, which underwent intramolecular alkylation to give, in good yield, the 3-aza-2-oxobicyclo[3.1.0]hexane 9 . This compound was subsequently converted into enantiomerically pure (−)- cis -2,3-methano-GABA, 2 .

From pyrrolidin-2-ones to 3-aza-2-oxobicyclo[3.2.0]heptanes. Synthesis of both enantiomers of cis-2-aminomethylcyclobutane carboxylic acid, a conformationally restricted analogue of GABA

Abstract By changing the cyclisation conditions (NaH in THF or NaOEt in EtOH), an enantiopure malonamide containing an enoate acceptor afforded either diastereomeric pyrrolidin-2-one 3 or 4 as the major product of the intramolecular conjugate addition. After separation, both diastereomers were converted through simple steps into the corresponding 3-aza-2-oxobicyclo[3.2.0] heptane which eventually led to each enantiomer of cis -2-aminomethylcyclobutanecarboxylic acid, 1 , a conformationally restricted analogue of GABA, in both enantiomerically pure form.

Accumulation of Cells With Short Telomeres Is Associated With Impaired Zinc Homeostasis and Inflammation in Old Hypertensive Participants

Critical shortening of telomeres, likely associated with a considerable increase of senescent cells, can be observed in PBMC of individuals aged 80 and older. We investigated the relationship between critical telomere shortening and zinc status in healthy or hypertensive participants with or without cardiovascular disease in old and very old participants. Telomere shortening and accumulation of cells with short telomeres (percent of cells with short telomeres) in advancing age was evident in patients and healthy controls, but exacerbated in those patients aged 80 and older. Moreover, in very old patients, the accumulation of % CST may impair intracellular zinc homeostasis and metallothioneins expression, which itself is linked to an increased number of inflammatory agents, thereby suggesting the existence of a possible causal relationship between % CST and zinc homeostasis. The determination of % CST could be a more reliable means than the simple measure of telomere length as fundamental parameter in ageing to determine whether individuals are still able to respond to stress.

Cyclisation of (R)- and (S)-N-allyl-N-(1-phenylethyl) methoxycarbonylacetamide mediated by Mn(III): Preparation and structural assignment of 3-aza-2-oxobicyclo[3.1.0]hexanes

Abstract (R)- and (S)-N-allyl-N-(1-phenylethyl)methoxycarbonylacetamide, 5 and 6, underwent oxidative cyclisation mediated by Mn(III), to give easily separable diastereomeric mixtures of 3-aza-2-oxobicyclo[3.1.0]hexanes 8a,b and 9a,b, respectively, whose structures were assigned on the basis of 1H NMR spectra and then confirmed by X-ray diffraction analysis of the derivatives 11b and 14.