Corrigendum: The silent epidemic of diabetic ketoacidosis at diagnosis of type 1 diabetes in children and adolescents in italy during the covid-19 pandemic in 2020.

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The Silent Epidemic of Diabetic Ketoacidosis at Diagnosis of Type 1 Diabetes in Children and Adolescents in Italy During the COVID-19 Pandemic in 2020.

Aim/Hypothesis: To compare the frequency of diabetic ketoacidosis (DKA) at diagnosis of type 1 diabetes in Italy during the COVID-19 pandemic in 2020 with the frequency of DKA during 2017-2019. Methods: Forty-seven pediatric diabetes centers caring for >90% of young people with diabetes in Italy recruited 4,237 newly diagnosed children with type 1 diabetes between 2017 and 2020 in a longitudinal study. Four subperiods in 2020 were defined based on government-imposed containment measures for COVID-19, and the frequencies of DKA and severe DKA compared with the same periods in 2017-2019. Results: Overall, the frequency of DKA increased from 35.7% (95%CI, 33.5-36.9) in 2017-2019 to 39.6% (95%CI, 36.7-42.4) in 2020 (p=0.008), while the frequency of severe DKA increased from 10.4% in 2017-2019 (95%CI, 9.4-11.5) to 14.2% in 2020 (95%CI, 12.3-16.4, p<0.001). DKA and severe DKA increased during the early pandemic period by 10.4% (p=0.004) and 8% (p=0.002), respectively, and the increase continued throughout 2020. Immigrant background increased and high household income decreased the probability of presenting with DKA (OR: 1.55; 95%CI, 1.24-1.94; p<0.001 and OR: 0.60; 95 CI, 0.41-0.88; p=0.010, respectively). Conclusions/Interpretation: There was an increase in the frequency of DKA and severe DKA in children newly diagnosed with type 1 diabetes during the COVID-19 pandemic in 2020, with no apparent association with the severity of COVID-19 infection severity or containment measures. There has been a silent outbreak of DKA in children during the pandemic, and preventive action is required to prevent this phenomenon in the event of further generalized lockdowns or future outbreaks.

Increasing trend of type 1 diabetes incidence in the pediatric population of the Calabria region in 2019-2021.

BACKGROUND: Although type 1 diabetes (T1D) represents one of the most common chronic diseases in pediatric age, few studies on the epidemiology of T1D exist globally and the exact prevalence and incidence rates of the disease are unknown. In many countries, including Italy, national registries are missing. METHODS: This study aims to assess T1D incidence in the pediatric population of the Calabria region (southern Italy) in the period 2019-2021. The secondary objective was to describe the main demographical, clinical and immunological features of incident cases. Case ascertainment and all clinical data were assessed by retrospectively reviewing the electronic medical records of children and adolescents diagnosed with diabetes at any Pediatric Diabetes Center belonging to the Rete Diabetologica Calabrese (Calabria Region Diabetes Network), from January 2019 to December 2021. The incidence of T1D was estimated for the entire region and was stratified according to age group (0-4 years, 5-9 years, and 10-14 years) and gender. Standardized incidence ratios for each province in the region were also calculated. RESULTS: The crude incidence of T1D was 20.6/100,000 person/years. Incidence rates were higher among females and children aged 5-9 years. The crude incidence of T1D was higher in the province of Reggio Calabria (26.5/100,000 person-years). The provinces of Crotone, Catanzaro, and Vibo Valentia showed significantly lower standardized incidence ratios. The annual incidence in the region progressively increased by 43% during the study period. CONCLUSIONS: Our study revealed a relatively high incidence in the Calabria region. The marked increasing incidence trend over the past two years could be related to the global impact of the COVID-19 pandemic, but further long-scale population-based studies are needed to confirm these findings.

A novel leptin antagonist peptide inhibits breast cancer growth in vitro and in vivo.

The role of the obesity cytokine leptin in breast cancer progression has raised interest in interfering with leptin's actions as a valuable therapeutic strategy. Leptin interacts with its receptor through three different binding sites: I-III. Site I is crucial for the formation of an active leptin-leptin receptor complex and in its subsequent activation. Amino acids 39-42 (Leu-Asp-Phe-Ile- LDFI) were shown to contribute to leptin binding site I and their mutations in alanine resulted in muteins acting as typical antagonists. We synthesized a small peptide based on the wild-type sequence of leptin binding site I (LDFI) and evaluated its efficacy in antagonizing leptin actions in breast cancer using in vitro and in vivo experimental models. The peptide LDFI abolished the leptin-induced anchorage-dependent and -independent growth as well as the migration of ERα-positive (MCF-7) and -negative (SKBR3) breast cancer cells. These results were well correlated with a reduction in the phosphorylation levels of leptin downstream effectors, as JAK2/STAT3/AKT/MAPK. Importantly, the peptide LDFI reversed the leptin-mediated up-regulation of its gene expression, as an additional mechanism able to enhance the peptide antagonistic activity. The described effects were specific for leptin signalling, since the developed peptide was not able to antagonize the other growth factors' actions on signalling activation, proliferation and migration. Finally, we showed that the LDFI pegylated peptide markedly reduced breast tumour growth in xenograft models. The unmodified peptide LDFI acting as a full leptin antagonist could become an attractive option for breast cancer treatment, especially in obese women.

Therapeutic potential of leptin receptor modulators.

Leptin, a pleiotropic molecule mainly produced by adipose tissue, was first discovered as a hormone controlling body weight and energy expenditure. In addition, leptin can modulate several processes in peripheral tissues such as immune response, fertility, hematopoiesis and carcinogenesis. The development of molecules that block or stimulate leptin receptor may therefore serve as a potent tool for studying the role of leptin in mammalian physiology and pathology, but it also may open new possibilities for therapy. This article presents an overview of current knowledge on leptin receptor modulators focusing on leptin mutein, leptin peptide modulators as well as small molecules with heterocyclic structure.

C → N and N → C solution phase peptide synthesis using the N-acyl 4-nitrobenzenesulfonamide as protection of the carboxylic function.

In this paper we describe a solution phase peptide synthesis strategy using the 4-nitrobenzenesulfonamido/N-methyl-4-nitrobenzenesulfonamido group as a protecting/activating system of the carboxyl function. The 4-nitrobenzenesulfonamido group is stable during peptide chain elongation (Fmoc chemistry). The N-aminoacyl or N-dipeptidyl-4-nitrobenzensulfonamides, when activated by methylation, can be easily coupled with another amino acid or reconverted into the free-carboxyl function amino acids or peptides. This activatable protecting group allows both the C → N and the N → C direction solution phase peptide synthesis. We also verified that the absolute configuration at the chiral centers does not change during the coupling reactions.

Quantitative determination of fatty acid chain composition in pork meat products by high resolution 1H NMR spectroscopy.

High resolution (1)H NMR spectroscopy was proposed for the determination of the fatty acid chain profile of lipids in pork meat products during ripening. Two typical Mediterranean PDO salami produced in Calabria, a region in the Southern Italy, were chosen as a case of study. Quantitative NMR analysis provided the fatty acid chain profiles of total lipid extracts. The transesterification of total lipid extracts furnished FAME mixtures that enabled quantitation of fatty acid acyl chains in the acylglycerol and FFA portions. In all cases, oleyl chains were predominant, and high amounts of polyunsaturated fatty acid chains were observed. The proposed spectroscopic method allowed also the estimation of the most important nutritional parameters of dry fermented meat products.

A one-pot procedure for the preparation of N-9-fluorenylmethyloxycarbonyl-α-amino diazoketones from α-amino acids.

The study describes a new "one-pot" route to the synthesis of N-9-fluorenylmethyloxycarbonyl (Fmoc) α-amino diazoketones. The procedure was tested on a series of commercially available free or side-chain protected α-amino acids employed as precursors. The conversion into the title compounds was achieved by masking and activating the α-amino acids with a single reagent, namely, 9-fluorenylmethyl chloroformate (Fmoc-Cl). The resulting N-protected mixed anhydrides were reacted with diazomethane to lead to the α-amino diazoketones, which were isolated by flash column chromatography in very good to excellent overall yields. The versatility of the procedure was verified on lipophilic α-amino acids and further demonstrated by the preparation of N-Fmoc-α-amino diazoketones also from α-amino acids containing side-chain masking groups, which are orthogonal to the Fmoc one. The results confirmed that tert-butyloxycarbonyl (Boc), tert-butyl ((t)Bu), and 2,2,4,6,7-pentamethyldihydrobenzofuran-5-sulfonyl (Pbf), three acid-labile protecting groups mostly adopted in the solution and solid-phase peptide synthesis, are compatible to the adopted reaction conditions. In all cases, the formation of the corresponding C-methyl ester of the starting amino acid was not observed. Moreover, the proposed method respects the chirality of the starting α-amino acids. No racemization occurred when the procedure was applied to the synthesis of the respective N-Fmoc-protected α-amino diazoketones from L-isoleucine and L-threonine and to the preparation of a diastereomeric pair of N-Fmoc-protected dipeptidyl diazoketones.

Simultaneous extraction and derivatization of amino acids and free fatty acids in meat products.

In meat products the contents of free amino acids and free fatty acids are two important parameters used to establish their quality. These compounds play a very important role in defining the sensorial characteristics and acceptability of meat products. An innovative procedure for the measurement of free amino acid and fatty acid contents in meat and meat derivatives was developed. A single experiment can be performed in order to determine simultaneously the free amino acid and free fatty acid profiles. The analytes of interest are rapidly extracted from the meat matrix and derivatized by using methyl chloroformate. This reagent allows the transformation of the two groups of analytes into the corresponding N-methyloxycarbonyl amino acid methyl esters and fatty acid methyl esters that can easily be extracted and sampled for their further identification and quantitation. The measurement of the obtained amino acid and fatty acid derivatives is performed by GC/MS analysis and their concentrations are calculated by using two appropriate internal standards. The main advantage of the proposed protocol is the determination at the same time of two important classes of analytes that are of great importance in food analysis and characterization. Moreover, minimal sample manipulation and preparation, and reduced total extraction times are required to obtain the response with respect to conventional procedures, in which instead the analysis of both the two classes of compounds must be performed separately. The helpfulness of the protocol was tested in the analysis of a cured meat product that is typical of the South of Italy. The optimized protocol successfully allowed the determination of thirteen free amino acids and six free fatty acids, namely those most abundant in the lipid content of the cured meat product under evaluation.

Dry fermented sausages of Southern Italy: a comparison of free amino acids and biogenic amines between industrial and homemade products.

This paper compares some important parameters and the free amino acid and biogenic amine contents of cured industrial and homemade meat products. To this aim, industrial and homemade "soppressata" and "salsiccia", typical dry fermented sausages produced in Southern Italy, were analyzed. The homemade sausages showed a higher level of free biogenic amines than that manufactured industrially, most likely because biogenic amine formation in industrial products is limited by the use of starter cultures. The industrial sausages are characterized by a higher total free amino acid content than the homemade products. Overall, free amino acid and biogenic amine contents demonstrated that appreciable differences exist between homemade and industrial sausages.

Transformations of 3-hydroxy steroids with lewis and anhydrous protic acids: the case of pregn-4-en-3ß,17α,20ß-triol.

The acid-catalyzed dehydration is one of the most important processes, which transforms 3-hydroxy steroids into their corresponding unsaturated derivatives. This reaction is of great importance because it can produce molecules that play a key role in the understanding of the natural metabolism of steroids. Sterol dehydration is generally performed with aqueous acidic systems, and the treatment often affords low yields of the desired compounds and/or complex mixtures of by-products. In this paper, we report the results obtained from the study of the structural and stereochemical effects of the acid-induced reaction of pregn-4-en-3ß,17α,20ß-triol in anhydrous systems. In particular, the treatment of this trihydroxy steroid model with Lewis acids leads to the corresponding Δ(3,5) -steradiene as the only product and in very high yields. With Lewis acids, no modifications of the 1,2-diol function on the D-ring are observed, even when the reactions are performed at high temperatures. Protic acid catalysis in non-aqueous organic solvents causes the formation of an epimeric mixture of the corresponding Δ(3,5) -steradiene derivatives by a partial stereochemical inversion of the asymmetric C-17. The reactivity of the 17α,20ß-diolic residue is also evaluated by exposing pregn-4-en-3ß,17α,20ß-triol and the corresponding Δ(3,5) -steradiene to the prolonged action of anhydrous protic acid systems under thermal conditions.

Site-selective methylation of N(beta)-nosyl hydrazides of N-nosyl protected alpha-amino acids.

The methylation reaction of N(beta)-nosyl hydrazides of N-nosyl protected alpha-amino acids by using diazomethane shows a controlled regiochemical trend and makes it possible to obtain the corresponding products methylated at specific positions depending on the amount of diazomethane used. The observed selectivity is closely connected with the different acidity of sulfonyl hydrazide, sulfonamide, and acyl hydrazine protons present in the analyzed substrates. The reactivity order of these three diverse reactive sites is supported by theoretical calculations. The hydrazine derivatives considered in this work belong to a class of compounds with interesting biological activity and of great interest in organic synthesis.

An efficient preparation of N-methyl-alpha-amino acids from N-nosyl-alpha-amino acid phenacyl esters.

In this paper we describe a simple and efficient solution-phase synthesis of N-methyl-N-nosyl-alpha-amino acids and N-Fmoc-N-methyl-alpha-amino acids. This represents a very important application in peptide synthesis to obtain N-methylated peptides in both solution and solid phase. The developed methodology involves the use of N-nosyl-alpha-amino acids with the carboxyl function protected as a phenacyl ester and the methylating reagent diazomethane. An important aspect of this synthetic strategy is the possibility to selectively deprotect the carboxyl function or alternatively both amino and carboxyl moieties by using the same reagent with a different molar excess and under mild conditions. Furthermore, the adopted procedure keeps unchanged the acid-sensitive side chain protecting groups used in Fmoc-based synthetic strategies.

A new non-natural arginine-like amino acid derivative with a sulfamoyl group in the side-chain.

Sulfamoylation of the L-ornithine methyl ester side-chain generates a non-natural arginine isostere which can be coupled with N-Fmoc-L-proline to synthesize analogues which maintain the structural characteristics of the biologically important Pro-Arg dipeptide sequence. As a probe of its biological importance, the sulfamoylated amino acid derivative was also incorporated as P1 residue in tripeptide structures matching the C-terminal subsequence of fibrinogen. The reported results demonstrate that the functionalization of L-ornithine side-chain with a neutral sulfamoyl group can generate an arginine bioisostere which can be used for the synthesis of prototypes of a new class of human thrombin inhibitors.