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SARS-CoV-2 infection, responsible for COVID-19, can determine cardiac events, which require a quick diagnosis and management, and should not be overlooked due to the presence of COVID-19 infection. In some cases, cardiovascular symptoms can also be the first and only manifestation of SARS-CoV-2 infection. In patients with COVID-19, the full cardiovascular disease diagnostic algorithm can be hindered by logistic restrain mainly derived from the difficulty of transporting patients in critical conditions to Radiology or Hemodynamics wards. The echocardiography in SARS-CoV-2 pandemic can help for differential diagnosis of cardiac events, which can be related or unrelated by the infection and can likely impact on short-term prognosis. Indeed, transthoracic echocardiography plays a key role in the screen for CV complications of COVID-19 infection: it must be focused cardiac ultrasound study (FoCUS) performed at bedside. All transthoracic, transesophageal and stress echocardiograms in patients in which test results are unlikely to change the management strategy should be postponed.

The European reference method (ERM) recognises the fraudulent addition of bovine (B) milk in water buffalo (WB) milk/dairy products based on concomitant isoelectric focusing (IEF) detection of B Beta2- and Beta3-CN fragments after corresponding plasminolysis. We here used proteomics to characterise false positive results occurring in the ERM as being due to WB Beta-CN(f100-209), which is also formed after plasminolysis of genuine WB milk/dairy products and comigrates in IEF with B Beta2-CN. These ERM limitations were overcome by a dedicated proteomic procedure based on loading of B/WB milk/cheese CN extracts on a hydroxyapatite column, in situ trypsinolysis and elution of B Beta-CN(f1-25)4P and WB Beta-CN(f1-28)4P proteotypic peptides. Based on their similar ionisation properties and resolution in MALDI-TOF-MS, these phosphopeptides were identified as suitable markers for detection of B material in WB milk/dairy products to a detection limit of 0.8% v/v. This proteomic procedure is here proposed as integrative/alternative to the ERM.

A "virtual two-dimensional (2D)-like" approach based on pH 2.5-6.0 gel isoelectrofocusing coupled to MALDI-TOF mass spectrometry (MS) was addressed for challenging the ovine casein heterogeneity due to polymorphism and post-translational modifications. The procedure enabled the identification of the main casein components including i) the four casein families at different degrees of phosphorylation, ii) nonallelic variants of either alpha(s1)- or alpha(s2)-CN, iii) differently glycosylated kappa-CN, and iv) high molecular mass proteolytic peptides. Protein assignment was confirmed by MALDI-TOF (MS) mass mapping of the tryptic digests, while phosphorylation sites were localized by tandem mass spectrometry. A straightforward identification was hindered by unexpected molecular mass shifts due to the oxidization of alpha(s1)- and the beta-CN. Indeed, using nano-ESI-MS, the casein sub-types were proved to contain a variable number of oxidized methionine residues. Data were additionally substantiated using polyclonal antibodies raised against the single casein families for immunolabelling purposes. The outcomes herein demonstrate the potentiality of the "virtual 2D-like" approach and provide indications useful for the inter-laboratory discrepancies in casein identification. They also greatly facilitate the comparison of data and the establishment of multi-user image-based isoelectrofocusing gels. (C) 2012 Elsevier Ltd. All rights reserved.

A study on casein genetic polymorphism in water buffalo milk of Mediterranean breed, reared in Southern Italy, was carried out by means of immunoelectrophoretic and chromatographic techniques coupled with mass spectrometry analysis. When compared with reference as1-CN variant A, the results showed the occurrence of a new as1-casein (as1-CN) B genetic variant having a single silent amino acid substitution Leu 178 (A)/ Ser 178 (B). In Mediterranean buffalo milks the allelic frequency of new as1-CN B was very similar to that determined in Mozzarella di bufala campana (MBC), a Protected Denomination of Origin (PDO) cheese, made exclusively from whole raw buffalo milk of this breed. The relative percentage of the two as1-CN variants, either in bulk milk or MBC cheese, can be used in defining the authenticity of PDO MBC cheese. Published by Elsevier Ltd.

At present, compared with bovine milk, the characterization of donkey milk caseins is at a relatively early stage progress, and only limited data are related to its genetic polymorphism. In this work, the heterogeneity of donkey caseome was investigated using a proteomic approach, based on one- (PAGE, UTLIEF) and two-dimensional (PAGE-->UTLIEF) electrophoresis, stained with either Coomassie Brilliant Blue or specific polyclonal antibodies, and structural MS analysis. These combined methodologies allowed the contemporary identification of donkey alpha(s1), alpha(s2), beta and kappa-CN with their related heterogeneity due to phosphorylation (alpha(s1), alpha(s2) and beta-CN), glycosylation (kappa-CN) and incorrect splicing of RNA in mRNA (deleted forms of alpha(s1)-CN and beta-CN). The results achieved showed 11 components for kappa-CN, six phosphorylated components for beta and alpha(s1)-CN and three main phosphorylated components for alpha(s2)-CN, each accounting for 10, 11 and 12 P/mole. At this regard, for the first time, the primary structure of the expressed protein corresponding to the only available donkey alpha(s2)-CN cDNA sequence was determined. Furthermore beta-CN was found in homozygous and heterozygous state for the occurrence of a genetic beta-CN variant having a MW value 28 mass units higher than the common beta-CN phenotype.

Etiolation of vegetables is a complex phenomenon implying qualitative and quantitative protein changes. The 2-DE protein profile of green and etiolated fleshy stalk samples has shown great differences in the 4–7 pH and 10 to 250 kDa mass range. Currently, a shortage of Cynara DNA or protein sequences has required the use of de novo sequencing and BLAST similarity searches for protein identification. Highlighted herein is an application of proteomics to the identification of proteins, which in a great part matched those from the Viridiplantae order. Quantitative evaluation, statistical analyses, and MALDI-TOF MS characterization of the resolved spots in green and etiolated samples of C. cardunculus enabled us to identify 46 out of 60 spots, containing 21 spots included conserved Viridiplantae domains. The etiolation process is discussed in light of the identification of some proteins involved in specific biochemical and metabolic pathways.

The unnatural amino acid lysinoalanine (LAL) has been identified in milk and cheese products by liquid chromatography mass spectrometry (LC/ESI/MS) with selective ion monitoring (SIM) of the 9-fluorenyl-methylchloro-formate (FMOC) derivative. LAL is not present in raw milk or derived from Mozzarella cheese; however, high amounts of LAL are found in calcium caseinate and milk powder. As expected, milk fortified with caseinate or whey protein powder produces cheese with higher LAL content. Our analytical procedure is based on the simultaneous detection of specific ion masses of the FMOC–LAL derivative and the N - e -methyl-lysine internal standard. A linear relationship was observed within the 0.2–20 ppm concentration range, in addition to a high correlation coefficient and ∼3% relative standard deviation.