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Purpose: Diabetes is a growing health problem. The aim of this study was to capture time trends in mortality associated with diabetes. Methods: The mortality database of the Veneto region (Italy) includes both the underlying causes of death, and all the diseases mentioned in the death certificate. The annual percent change (APC) in age-standardized rates from 2008 to 2017 was computed by the Joinpoint Regression Program. Results: Overall 453,972 deaths (56,074 with mention of diabetes) were observed among subjects aged ≥ 40 years. Mortality rates declined for diabetes as the underlying cause of death and from diabetes-related circulatory diseases. The latter declined especially in females − 4.4 (CI 95% − 5.3/− 3.4), while in males the APC was − 2.8 (CI 95% − 4.0/− 1.6). Conclusion: We observed a significant reduction in mortality during the period 2008–2017 in diabetes either as underlying cause of death or when all mentions of diabetes in the death certificate were considered.

Aib‐rich side‐chain lactam‐bridged oligomers Ac‐($\rm{G{\overline{lu-Aib-Aib-Ly}s}}$)n‐Ala‐OH with n = 1,2,3 were designed and synthesized as putative models of the 310‐helix. The lactam bridge between the side chains of L‐Glu and L‐Lys in (i) − (i + 3) positions was introduced in order to enhance the structural preference toward the right‐handed 310‐helix. The conformational properties of the three peptides were studied in trifluoroethanol (TFE) solution by CD, NMR, and computer simulations. The structural information was derived mainly from the analysis of nuclear Overhauser effect spectroscopy spectra. The presence of αH(i)—HN(i + 2) and of αH(i)—HN(i + 3) connectivities and the absence of αH(i)—HN(i + 4) connectivities indicate that these peptides fold into a 310‐helix rather than into an α‐helix. Based on these conformational features, stereospecific assignment of the Aib methyl groups was possible. The results of such experiments and of the subsequent distance geometry and restrained molecular dynamics simulations reveal a marked preference of these peptides for 310‐helix. The CD spectra of these peptides indicate that the helix content increases upon chain elongation. The CD spectrum of the trimer is characterized by a negative band at 200 nm and by a weak positive band around 220 nm. The CD spectrum in TFE is different from that observed in aqueous solution in the presence of SDS micelles, reported in our previous work, and from those reported by a different research group for 310‐helical peptides. A possible reason for these differences could rest in the presence of different equilibria of the conformer populations of the various peptides in different solvent systems. © 2005 Wiley Periodicals, Inc. Biopolymers (Pept Sci), 2005

The N-terminal 1–34 segment of parathyroid hormone (PTH) is fully active in vitro and in vivo and it can reproduce all biological responses in bone characteristic of the native intact PTH. Recent studies have demonstrated that N-terminal fragments presenting the principal activating domain such as PTH(1–11) and PTH(1–14) with helicity-enhancing substitutions yield potent analogues with PTH(1–34)-like activity. To further investigate the role of α-helicity on biological potency, we designed and synthesized by solid-phase methodology the following hPTH(1–11) analogues substituted at positions 1 and/or 3 by the sterically hindered and helix-promoting Cα-tetrasubstituted α-amino acids α-amino isobutyric acid (Aib), 1-aminocyclopentane-1-carboxylic acid (Ac5c) and 1-aminocyclohexane-1-carboxylic acid (Ac6c): Ac5c-V-Aib-E-I-Q-L-M-H-Q-R-NH2 (I); Aib-V-Ac5c-E-I-Q-L-M-H-Q-R-NH2 (II); Ac6c-V-Aib-E-I-Q-L-M-H-Q-R-NH2 (III); Aib-V-Ac6c-E-I-Q-L-M-H-Q-R-NH2 (IV); Aib-V-Aib-E-I-Q-L-M-H-Q-R-NH2 (V); S-V-Aib-E-I-Q-L-M-H-Q-R-NH2 (VI), S-V-Ac5c-E-I-Q-L-M-H-Q-R-NH2 (VII); Ac5c-V-S-E-I-Q-L-M-H-Q-R-NH2 (VIII); Ac6c-V-S-E-I-Q-L-M-H-Q-R-NH2 (IX); Ac5c-V-Ac5c-E-I-Q-L-M-H-Q-R-NH2 (X); Ac6c-V-Ac6c-E-I-Q-L-M-H-Q-R-NH2 (XI). All analogues were biologically evaluated and conformationally characterized in 2,2,2-trifluoroethanol (TFE) solution by circular dichroism (CD). Analogues I–V, which cover the full range of biological activity observed in the present study, were further conformationally characterized in detail by nuclear magnetic resonance (NMR) and computer simulations studies. The results of ligand-stimulated cAMP accumulation experiments indicated that analogues I and II are active, analogues III, VI and VII are very weakly active and analogues IV, V, VIII–XI are inactive. The most potent analogue, I exhibits biological activity 3500-fold higher than that of the native PTH(1–11) and only 15-fold weaker than that of the native sequence hPTH(1–34). Remarkably, the two most potent analogues, I and II, and the very weakly active analogues, VI and VII, exhibit similar helix contents. These results indicate that the presence of a stable N-terminal helical sequence is an important but not sufficient condition for biological activity.

The N-terminal 1–34 fragments of the parathyroid hormone (PTH) and parathyroid hormone-related protein (PTHrP) elicit the full spectrum of bone-related biological activities of the intact native sequences. It has been suggested that the structural elements essential for bioactivity are two helical segments located at the N-terminal and C-terminal sequences, connected by hinges or flexible points around positions 12 and 19. In order to assess the relevance of the local conformation around Gly¹² upon biological function, we synthesized and characterized the following PTH(1–34) analogues containing Aib residues: (I) A-V-S-E-I-Q-F-nL-H-N-Aib-G-K-H-L-S-S-nL-E-R-V-E-Nal-L-R-K-K-L-Q-D-V-H-N-Y-NH2 {[Nle^8,18, Aib¹¹, Nal²³,Tyr³⁴]bPTH(1–34)–NH2}; (II) A-V-S-E-I-Q-F-nL-H-N-L-Aib-K-H-L-S-S-nL-E-R-V-E-Nal-L-R-K-K-L-Q-D-V-H-N-Y-NH2 {[Nle^8,18, Aib¹²,Nal²³,Tyr³⁴]bPTH(1–34)–NH2}; (III) A-V-S-E-I-Q-F-nL-H-N-L-G-Aib-H-L-S-S-nL-E-R-V-E-Nal-L-R-K-K-L-Q-D-V-H-N-Y-NH2 {[Nle^8,18, Aib¹³, Nal²³,Tyr³⁴]bPTH(1–34)–NH2}; (IV) A-V-S-E-I-Q-F-nL-H-N-Aib-Aib-K-H-L-S-S-nL-E-R-V-E-Nal-L-R-K-K-L-Q-D-V-H-N-YNH2 {[Nle^8,18, Aib^11,12, Nal²³,Tyr³⁴]bPTH(1–34)–NH2}; (V) A-V-S-E-I-Q-F-nL-H-N-L-Aib-Aib-H-L-S-S-nL-E-R-V-E-Nal-L-R-K-K-L-Q-D-V-H-N-Y-NH2 {[Nle^8,18, Aib^12,13,Nal²³,Tyr³⁴]bPTH(1–34)–NH2}. (nL= Nle; Nal= L-(2-naphthyl)-alanine; Aib= α-amino-isobutyric acid.) The introduction of Aib residues at position 11 in analogue I or at positions 11 and 12 in analogue IV resulted in a 5–20-fold lower efficacy and a substantial loss of binding affinity compared to the parent compound [Nle^8,18, Nal²³,Tyr³⁴]bPTH(1–34)–NH2. Both binding affinity and adenylyl cyclase stimulation activity are largely restored when the Aib residues are introduced at position 12 in analogue II, 13 in analogue III, and 12–13 in analogue V. The conformational properties of the analogues in aqueous solution containing dodecylphosphocholine micelles were studied by CD, two-dimensional (2D) NMR and computer simulations. The results indicated the presence of two helical segments in all analogues, located at the N-terminal and C-terminal sequences. Insertion of Aib residues at positions 12 and 13, or of Aib dyads at positions 11–12 and 12–13, enhances the stability of the N-terminal helix of all analogues. In all analogues the Aib residues are included in the helical segments. These results confirmed the importance of the helical structure in the N-terminal activation domain, as well as of the presence of the Leu¹¹ hydrophobic side chain in the native sequence, for PTH-like bioactivity. © 2003 Wiley Periodicals, Inc. Biopolymers: 437–457, 2003

An analogue of the human granulocyte–macrophage colony-stimulating factor (hGM-CSF), hGM-CSF(13–27)–Gly–(75–87) was synthesized by solid phase methodology. This analogue was designed to comprise helices A and C of the native growth factor, linked by a glycine bridge. Helices A and C form half of a four-helix bundle motif in the crystal structure of the native factor and are involved in the interaction with α- and β-chains of the heterodimeric receptor. A conformational analysis of the synthetic analogue by CD, two-dimensional nmr spectroscopy, and molecular dynamics calculations is reported. The analogue is in a random structure in water and assumes a partially α-helical conformation in a 1 : 1 trifluoroethanol/water mixture. The helix content in this medium is ~ 70%. By 2D-nmr spectroscopy, two helical segments were identified in the sequences corresponding to helices A and C. In addition to medium- and short-range NOESY connectivities, a long-range cross peak was found between the Cβ proton of Val¹⁶ and NH proton of His⁸⁷ (using the numbering of the native protein). Experimentally derived interproton distances were used as restraints in molecular dynamics calculations, utilizing the x-ray coordinates as the initial structure. The final structure is characterized by two helical segments in close spatial proximity, connected by a loop region. This structure is similar to that of the corresponding domain in the x-ray structure of the native growth factor in which helices A and C are oriented in an antiparallel fashion. The N-terminal residues Gly–Pro of helix C are involved in an irregular turn connecting the two helical segments. As a consequence, helix C is appreciably shifted and slightly rotated with respect to helix A compared to the x-ray structure of the native growth factor. These small differences in the topology of the two helices could explain the lower biological activity of this analogue with respect to that of the native growth factor. © 1999 John Wiley & Sons, Inc. Biopoly 50: 545–554, 1999

A conformational study in solution of the fatty acid binding protein from chicken liver is presented. The nearly complete sequence-specific ¹H resonance assignment was achieved from homonuclear two-dimensional nmr experiments using a sample of native protein. The principal elements of secondary structure were identified: 10 antiparallel β-strands and one helical segment followed by a turn comprising 5 residues. These elements correspond closely with those of the crystal structure of the related protein, and two new secondary structural features obtained from the nmr data are the β-sheet conformation between the first and the last β-strand in the protein sequence, as well as a helical loop at the N-terminus of the polypeptide chain. © 1999 John Wiley & Sons, Inc. Biopoly 50: 1–11, 1999

On the basis of the X‐ray structure and results from structure‐‐activity relationship studies, the following GM–CSF analogue was designed and synthesized by solid‐phase methodology: hGM–CSF[13‐31]‐Gly‐Pro‐Gly‐[103–116]‐NH2. This analogue was constructed to comprise helices A and D of the native hGM–CSF, covalently linked in an antiparallel orientation by the tripeptide spacer Gly‐Pro‐Gly, which is known as a turn‐inducing sequence. The conformational analysis of the analogue by CD spectroscopy revealed an essentially random structure in water, while α‐helix formation was observed upon addition of TFE. In 40% TFE the helix content was ∼45%. By two‐dimensional NMR experiments in 1:1 water/trifluoroethanol mixture two helical sequences were identified comprising the segments corresponding to helix A and helix D. In addition to medium‐range NOESY connectivities, a long‐range cross‐peak was found involving the leucine residues at positions 13 and 35. Based on the experimentally derived data (54 NOEs), the structure was refined by restrained molecular dynamics simulations over 120 ps at various temperatures. A representative conformation derived from the computer simulation is mainly characterized by two helical segments connected by a loop region. The overall three‐dimensional structure of the analogue is comparable to the X‐ray structure of hGM–CSF in that helices A and D are oriented in an antiparallel fashion, forming a two α‐helix bundle. Nevertheless, there are small differences in the topology of the helices between the solution structure of the designed analogue and the X‐ray structure of hGM–CSF. The possible implications of these conformational features at the effects of biological activity are discussed. © 1997 European Peptide Society and John Wiley & Sons, Ltd.