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The merging of micellar and photoredox catalysis represents a key issue to promote “in water” photochemical transformations. A photomicellar catalyzed synthesis of amides from N-methyl-N-alkyl aromatic amines and both aliphatic and aromatic isocyanides is herein presented. The mild reaction conditions enabled a wide substrate scope and a good functional groups tolerance, as further shown in the late-stage functionalization of complex bioactive scaffolds. Furthermore, solution 1D and 2D NMR experiments performed, for the first time, in the presence of paramagnetic probes enabled the study of the reaction environment at the atomic level along with the localization of the photocatalyst with respect to the micelles, thus providing experimental data to drive the identification of optimum photocatalyst/surfactant pairing.

The pharmacodynamic and pharmacokinetic properties of bioactive peptides can be modulated by introducing conformational constraints such as intramolecular macrocyclizations, which can involve either the backbone and/or side chains. Herein, we aimed at increasing the α-helicity content of temporin L, an isoform of an intriguing class of linear antimicrobial peptides (AMPs), endowed with a wide antimicrobial spectrum, by the employment of diverse side-chain tethering strategies, including lactam, 1,4-substituted [1,2,3]-triazole, hydrocarbon, and disulfide linkers. Our approach resulted in a library of cyclic temporin L analogues that were biologically assessed for their antimicrobial, cytotoxic, and antibiofilm activities, leading to the development of the first-in-class cyclic peptide related to this AMP family. Our results allowed us to expand the knowledge regarding the relationship between the α-helical character of temporin derivatives and their biological activity, paving the way for the development of improved antibiotic cyclic AMP analogues.

Background Treatment of end-stage kidney disease patients is extremely challenging given the interconnected functional derangements and comorbidities characterizing the disease. Continuous quality improvement (CQI) in healthcare is a structured clinical governance process helping physicians adhere to best clinical practices. The digitization of patient medical records and data warehousing technologies has standardized and enhanced the efficiency of the CQI’s evidence generation process. There is limited evidence that ameliorating intermediate outcomes would translate into better patient-centred outcomes. We sought to evaluate the relationship between Fresenius Medical Care medical patient review CQI (MPR-CQI) implementation and patients’ survival in a large historical cohort study. Methods We included all incident adult patients with 6-months survival on chronic dialysis registered in the Europe, Middle East and Africa region between 2011 and 2018. We compared medical key performance indicator (KPI) target achievements and 2-year mortality for patients enrolled prior to and after MPR-CQI policy onset (Cohorts A and B). We adopted a structural equation model where MPR-CQI policy was the exogenous explanatory variable, KPI target achievements was the mediator variable and survival was the outcome of interest. Results About 4270 patients (Cohort A: 2397; Cohort B: 1873) met the inclusion criteria. We observed an increase in KPI target achievements after MPR-CQI policy implementation. Mediation analysis demonstrated a significant reduction in mortality due to an indirect effect of MPR-CQI implementation through improvement in KPI target achievement occurring in the post-implementation era [odds ratio 0.70 (95% confidence interval 0.65–0.76); P Conclusions Our study suggests that MPR-CQI achieved by standardized clinical practice and periodic structured MPR may improve patients’ survival through improvement in medical KPIs.

Background: Vascular access surveillance of dialysis patients is a challenging task for clinicians. We derived and validated an arteriovenous fistula failure model (AVF-FM) based on machine learning. Methods: The AVF-FM is an XG-Boost algorithm aimed at predicting AVF failure within three months among in-centre dialysis patients. The model was trained in the derivation set (70% of initial cohort) by exploiting the information routinely collected in the Nephrocare European Clinical Database (EuCliD®). Model performance was tested by concordance statistic and calibration charts in the remaining 30% of records. Features importance was computed using the SHAP method. Results: We included 13,369 patients, overall. The Area Under the ROC Curve (AUC-ROC) of AVF-FM was 0.80 (95% CI 0.79–0.81). Model calibration showed excellent representation of observed failure risk. Variables associated with the greatest impact on risk estimates were previous history of AVF complications, followed by access recirculation and other functional parameters including metrics describing temporal pattern of dialysis dose, blood flow, dynamic venous and arterial pressures. Conclusions: The AVF-FM achieved good discrimination and calibration properties by combining routinely collected clinical and sensor data that require no additional effort by healthcare staff. Therefore, it can potentially enable risk-based personalization of AVF surveillance strategies.

Protein complex formation depends on the interplay between preorganization and flexibility of the binding epitopes involved. The design of epitope mimetics typically focuses on stabilizing a particular bioactive conformation, often without considering conformational dynamics, which limits the potential of peptidomimetics against challenging targets such as transcription factors. We developed a peptide‐derived inhibitor of the NF‐Y transcription factor by first constraining the conformation of an epitope through hydrocarbon stapling and then fine‐tuning its flexibility. In the initial set of constrained peptides, a single non‐interacting α‐methyl group was observed to have a detrimental effect on complex stability. Biophysical characterization revealed how this methyl group affects the conformation of the peptide in its bound state. Adaption of the methylation pattern resulted in a peptide that inhibits transcription factor assembly and subsequent recruitment to the target DNA., Set Me free: A peptide‐derived inhibitor of the NF‐Y transcription factor was developed by constraining the conformation of an epitope through hydrocarbon stapling and then fine‐tuning its flexibility. In the initial set of constrained peptides, a non‐interacting α‐methyl group was observed to have a detrimental effect on complex stability. Adaption of the methylation pattern gave a peptide that inhibits transcription factor assembly and subsequent DNA binding.

The i-motif is a biologically relevant non-canonical DNA structure formed by cytosine-rich sequences. Despite the importance of the factors affecting the formation/stability of such a structure, like pH, cation type and concentration, no systematic study that simultaneously analysed their effect on the i-motif in vitro has been carried out so far. Therefore, here we report a systematic study that aims to evaluate the effect of these factors, and their possible interaction, on the formation of an i-motif structure. Our results confirm that pH plays the main role in i-motif formation. However, we demonstrate that the effect of the cation concentration on the i-motif is strictly dependent on the pH, while no significant differences are observed among the investigated cation types. Graphical abstract.

HMGB1 is a ubiquitous non-histone protein, which biological effects depend on its expression and subcellular location. Inside the nucleus, HMGB1 is engaged in many DNA events such as DNA repair, transcription and telomere maintenance. HMGB1 has been reported to bind preferentially to bent DNA as well as to noncanonical DNA structures like 4-way junctions and, more recently, to G-quadruplexes. These are four-stranded conformations of nucleic acids involved in important cellular processes, including telomere maintenance. In this frame, G-quadruplex recognition by specific proteins represents a key event to modulate physiological or pathological pathways. Herein, to get insights into the telomeric G-quadruplex DNA recognition by HMGB1, we performed detailed biophysical studies complemented with biological analyses. The obtained results provided information about the molecular determinants for the interaction and showed that the structural variability of human telomeric G-quadruplex DNA may have significant implications in HMGB1 recognition. The biological data identified HMGB1 as a telomere-associated protein in both telomerase-positive and -negative tumor cells and showed that HMGB1 gene silencing in such cells induces telomere DNA damage foci. Altogether, these findings provide a deeper understanding of telomeric G-quadruplex recognition by HMGB1 and suggest that this protein could actually represent a new target for cancer therapy.

Long-term survivors of glioblastoma multiforme (GBM) are at high risk of developing second primary neoplasms, including leukemia. For these patients, the use of classic tyrosine kinase inhibitors (TKIs), such as imatinib mesylate, is strongly discouraged, since this treatment causes a tremendous increase of tumor and stem cell migration and invasion. We aimed to develop agents useful for the treatment of patients with GBM and chronic myeloid leukemia (CML) using an alternative mechanism of action from the TKIs, specifically based on the inhibition of tubulin polymerization. Compounds 7 and 25, as planned, not only inhibited tubulin polymerization, but also inhibited the proliferation of both GMB and CML cells, including those expressing the T315I mutation, at nanomolar concentrations. In in vivo experiments in BALB/cnu/nu mice injected subcutaneously with U87MG cells, in vivo, 7 significantly inhibited GBM cancer cell proliferation, in vivo tumorigenesis, and tumor growth, tumorigenesis and angiogenesis. Compound 7 was found to block human topoisomerase II (hTopoII) selectively and completely, at a concentration of 100 μM.

The inhibition of the PD-1/PD-L1 axis by monoclonal antibodies has achieved remarkable success in treating a growing number of cancers. However, a novel class of small organic molecules, with BMS-202 (1) as the lead, is emerging as direct PD-L1 inhibitors. Herein, we report a series of 2,4,6-tri- and 2,4-disubstituted 1,3,5-triazines, which were synthesized and assayed for their PD-L1 binding by NMR and homogeneous time-resolved fluorescence. Among them, compound 10 demonstrated to strongly bind with the PD-L1 protein and challenged it in a co-culture of PD-L1 expressing cancer cells (PC9 and HCC827 cells) and peripheral blood mononuclear cells enhanced antitumor immune activity of the latter. Compound 10 significantly increased interferon γ release and apoptotic induction of cancer cells, with low cytotoxicity in healthy cells when compared to 1, thus paving the way for subsequent preclinical optimization and medical applications.

This article collects the personal stories of the young doctors who in the early sixties contributed to the birth and development of the Croff pavilion at the Policlinico Hospital in Milan. Inaugurated on October 19, 1964, this has been the first institute in Italy entirely devoted to patients with kidney diseases. Since its inception, it has significantly contributed to the progress of nephrology thanks to important and pioneering investigations in the main fields of our specialty, which still continue nowadays. The different stories reported here follow the chronological order in which the young doctors arrived at Croff, each story representing a personal narrative that interweaves and integrates that of others. This gives rise to a vivid many-voiced account, from which emerge not only the figures of these young doctors, but also those of patients, nurses, and laboratory technicians.

Treatment of respiratory viral infections remains a global health concern, mainly due to the inefficacy of available drugs. Therefore, the discovery of novel antiviral com-pounds is needed; in this context, antimicrobial peptides (AMPs) like temporins hold great promise. Here, we discovered that the harmless temporin G (TG) significantly inhibited the early life-cycle phases of influenza virus. The in vitro hemagglutinating test revealed the existence of TG interaction with the viral hemagglutinin (HA) pro-tein. Furthermore, the hemolysis inhibition assay and the molecular docking studies confirmed a TG/HA complex formation at the level of the conserved hydrophobic stem groove of HA. Remarkably, these findings highlight the ability of TG to block the conformational rearrangements of HA2 subunit, which are essential for the viral envelope fusion with intracellular endocytic vesicles, thereby neutralizing the virus entry into the host cell. In comparison, in the case of parainfluenza virus, which pen-etrates host cells upon a membrane-fusion process, addition of TG to infected cells provoked ~1.2 log reduction of viral titer released in the supernatant. Nevertheless, at the same condition, an immunofluorescent assay showed that the expression of viral hemagglutinin/neuraminidase protein was not significantly reduced. This suggested a peptide-mediated block of some late steps of viral replication and therefore the im-pairment of the extracellular release of viral particles. Overall, our results are the first demonstration of the ability of an AMP to interfere with the replication of respiratory viruses with a different mechanism of cell entry and will open a new avenue for the development of novel therapeutic approaches against a large variety of respiratory viruses, including the recent SARS-CoV2.

Among peritumoral cells, cancer-associated fibroblasts (CAFs) are major facilitators of tumor progression. This study describes the effects of two urokinase-derived, novel decapeptides, denoted as Pep 1 and its cyclic derivative Pep 2. In a mouse model of tumor dissemination, using HT1080 fibrosarcoma cells, Pep 2 reduced the number and size of lung metastases. Specific binding of fluoresceinated Pep 2 to HT1080 and telomerase immortalised fibroblasts (TIF) cell surfaces was enhanced by &alpha, v overexpression or abolished by excess vitronectin, anti-&alpha, v antibodies or silencing of ITGAV &alpha, v gene, identifying &alpha, v-integrin as the Pep 2 molecular target. In 3D-organotypic assays, peptide-exposed TIFs and primary CAFs from breast carcinoma patients both exhibited a markedly reduced pro-invasive ability of either HT1080 fibrosarcoma or MDA-MB-231 mammary carcinoma cells, respectively. Furthermore, TIFs, either exposed to Pep 2, or silenced for &alpha, v integrin, were impaired in their ability to chemoattract cancer cells and to contract collagen matrices, exhibiting reduced &alpha, smooth muscle actin (&alpha, SMA) levels. Finally, peptide exposure of &alpha, v-expressing primary CAFs led to the downregulation of &alpha, SMA protein and to a dramatic reduction of their pro-invasive capability. In conclusion, the ability of the novel decapeptides to interfere with tumor cell invasion directly and through the down-modulation of CAF phenotype suggests their use as lead compounds for co-targeting anti-cancer strategies.

[Image: see text] Protein–protein interactions (PPIs) contribute to the onset and/or progression of several diseases, especially cancer, and this discovery has paved the way for considering disruption of the PPIs as an attractive anti-tumor strategy. In this regard, simple and efficient biophysical methods for detecting the interaction of the inhibitors with the protein counterpart are still in high demand. Herein, we describe a convenient NMR method for the screening of putative PPI inhibitors based on the use of “hot peptides” (HOPPI-NMR). As a case study, HOPPI-NMR was successful applied to the well-known p53/MDM2 system. Our outcomes highlight the main advantages of the method, including the use of a small amount of unlabeled proteins, the minimization of the risk of protein aggregation, and the ability to identify weak binders. The last leaves open the possibility for application of HOPPI-NMR in tandem with fragment-based drug discovery as a valid strategy for the identification of novel chemotypes acting as PPI inhibitors.

Here we investigatethe structural and biological effects ensuing form the disulfide bond replacement of a potent and selective C-X-C chemokine receptor type 4 (CXCR4) peptide antagonist, with 1,4- and 1,5- disubstituted 1,2,3-triazole moieties. Both strategies produced candidates that showed high affinity and selectivity against CXCR4. Notably, when assessed for their ability to modulate the CXCL12-mediated cell migration, the 1,4-triazole variant conserved the antagonistic effect in the low-mid nanomolar range, while the 1,5-triazole one displayed the ability to activate the migration, becoming the first in class low-molecular-weight CXCR4 peptide agonist. By combining NMR and computational studies, we provided a valuable model that highlighted differences in the interactions of the two peptidomimetics with the receptor that could account for their different functional profile. Finally, we envisage that our findings could be translated to different GPCR-interacting peptides for the pursuit of novel chemical probes that could assist in dissecting the complex puzzle of this fundamental class of transmembrane receptors.

Background: Fluid volume and blood pressure (BP) management are crucial endpoints for end-stage kidney disease patients. BP control in clinical practice mainly relies on reducing extracellular fluid volume overload by diminishing targeted postdialysis weight. This approach exposes dialysis patients to intradialytic hypotensive episodes. Summary: Both chronic hypertension and intradialytic hypotension lead to adverse long-term outcomes. Achieving the optimal trade-off between adequate fluid removal and the risk of intradialytic adverse events is a complex task in clinical practice given the multiple patient-related and dialysis-related factors affecting the hemodynamic response to treatment. State-of-the-art artificial intelligence has been adopted in other complex decision-making tasks for dialysis patients and may help personalize the multiple dialysis-related prescriptions affecting patients’ intradialytic hemodynamics. As a proof of concept, we developed a multiple-endpoint model predicting session-specific Kt/V, fluid volume removal, heart rate, and BP based on patient characteristics, historic hemodynamic responses, and dialysis-related prescriptions. Key Messages: The accuracy and precision of this preliminary model is extremely encouraging. Such analytic tools may be used to anticipate patients’ reactions through simulation so that the best strategy can be chosen based on clinical judgment or formal utility functions.

Concern over antibiotic resistance is growing, and new classes of antibiotics, particularly against Gram-negative bacteria, are needed. Antimicrobial peptides (AMPs) have been proposed as a new class of clinically useful antimicrobials. Special attention has been devoted to frog-skin temporins. In particular, temporin L (TL) is strongly active against Gram-positive, Gram-negative bacteria and yeast strains. With the aim of overcoming some of the main drawbacks preventing the widespread clinical use of this peptide, i.e. toxicity and unfavorable pharmacokinetics profile, we designed new formulations combining TL with different types of cyclodextrins (CDs). TL was associated to a panel of neutral or negatively charged, monomeric and polymeric CDs. The impact of CDs association on TL solubility, as well as the transport through bacterial alginates was assessed. The biocompatibility on human cells together with the antimicrobial and antibiofilm properties of TL/CD systems was explored.

This work describes the synthesis of thirteen cyclooctapeptides dicarba-analogues of Somatostatin, containing l- or d-allylglycine (Agl) residues at the termini of the peptide chain, through on resin Ring Closing Metathesis (RCM) of the linear octapeptides. We investigated the influence of the stereochemistry of some strategic amino acids on the propensity to give the cyclic compounds in mild conditions (refluxing DCM). Systematic individual replacement of Phe6,7,11 residues with the corresponding enantiomers, strongly favoured the ring closure by conventional heating. The yield of the cyclic products was strictly correlated to the position of this amino acid on the peptide chain. In particular substitution of Phe6 by Tyr in peptides which did not give the cyclic compounds, allowed the ring formation. The effect of the phenolic −OH function of Tyr side chain on the proximity of the terminal Agl residue was studied by NMR techniques. All the linear precursors gave cyclic somatostatin dicarba-analogues, in good to high yields and in short reaction times, by microwave-assisted RCM, performed with the 2nd generation Grubbs catalyst. The unsaturated dicarba-tether resulted in a mixture of E and Z stereoisomers in a variable ratio, depending on the sequence and the cyclization method. The E isomer was largely the most abundant in all but one the described product.

Besides the well-known double-helical conformation, DNA is capable of folding into various noncanonical arrangements, such as G-quadruplexes (G4s) and i-motifs (iMs), whose occurrence in gene promoters, replication origins, and telomeres highlights the breadth of biological processes that they might regulate. Particularly, previous studies have reported that G4 and iM structures may play different roles in controlling gene transcription. Anyway, molecular tools able to simultaneously stabilize/destabilize those structures are still needed to shed light on what happens at the biological level. Herein, a multicomponent reaction and a click chemistry functionalization were combined to generate a set of 31 bis-triazolyl-pyridine derivatives which were initially screened by circular dichroism for their ability to interact with different G4 and/or iM DNAs and to affect the thermal stability of these structures. All the compounds were then clustered through multivariate data analysis, based on such capability. The most promising compounds were subjected to a further biophysical and biological characterization, leading to the identification of two molecules simultaneously able to stabilize G4s and destabilize iMs, both in vitro and in living cells.

Transcription factors (TFs) have a remarkable role in the homeostasis of the organisms and there is a growing interest in how they recognize and interact with specific DNA sequences. TFs recognize DNA using a variety of structural motifs. Among those, the ribbon-helix-helix (RHH) proteins, exemplified by the MetJ and ARC repressors, form dimers that insert antiparallel β-sheets into the major groove of DNA. A great chemical challenge consists of using the principles of DNA recognition by TFs to design minimized peptides that maintain the DNA affinity and specificity characteristics of the natural counterparts. In this context, a peptide mimic of an antiparallel β-sheet is very attractive since it can be obtained by a single peptide chain folding in a β-hairpin structure and can be as short as 14 amino acids or less. Herein, we designed eight linear and two cyclic dodeca-peptides endowed with β-hairpins. Their DNA binding properties have been investigated using fluorescence spectroscopy together with the conformational analysis through circular dichroism and solution NMR. We found that one of our peptides, peptide 6, is able to bind DNA, albeit without sequence selectivity. Notably, it shows a topological selectivity for the major groove of the DNA which is the interaction site of ARC and many other DNA-binding proteins. Moreover, we found that a type I' β-hairpin folding pattern is a favorite peptide structure for interaction with the B-DNA major groove. Peptide 6 is a valuable lead compound for the development of novel analogs with sequence selectivity.

The cellular toxicity of copper is usually associated with its ability to generate reactive oxygen species. However, recent studies in bacterial organisms showed that copper toxicity is also strictly connected to iron-sulfur cluster proteins and to their assembly processes. Mitochondria of eukaryotic cells contain a labile copper(I) pool localized in the matrix where also the mitochondrial iron-sulfur (Fe/S) cluster assembly machinery resides to mature mitochondrial Fe/S cluster-containing proteins. Misregulation of copper homeostasis might therefore damage mitochondrial Fe/S protein maturation. To describe, from a molecular perspective, the effects of copper(I) toxicity on such a maturation process, we have here investigated the still unknown mechanism of [4Fe-4S] cluster formation conducted by the mitochondrial ISCA1/ISCA2 and GLRX5 proteins, and defined how copper(I) can impair this process. The molecular model here proposed indicates that the copper(I) and Fe/S protein maturation cellular pathways need to be strictly regulated to avoid copper(I) ion from blocking mitochondrial [4Fe-4S] protein maturation.

International audience; In accordance with their common but also divergent physiological actions, human urotensin II (1) and urotensin II-related peptide (2) could stabilize specific urotensin II receptor (UTR) conformations, thereby activating different signaling pathways, a feature referred to as biased agonism or functional selectivity. Sequential N-methylation of the amides in the conserved core sequence of 1, 2, and fragment U-II4-11 (3) shed light on structural requirements involved in their functional selectivity. Thus, 18 N-methylated UTR ligands were synthesized and their biological profiles evaluated using in vitro competition binding assays, ex vivo rat aortic ring bioassays and BRET-based biosensor experiments. Biological activity diverged from that of the parent structures contingent on the location of amide methylation, indicating relevant hydrogen-bond interactions for the function of the endogenous peptides. Conformational analysis of selected N-methyl analogs indicated the importance of specific amide residues of 2 for the distinct pharmacology relative to 1 and 3.

Background The clinical management of chronic kidney disease-mineral bone disorder (CKD-MBD) remains extremely challenging, partially due to difficulties in defining high-risk phenotypes based on serum biomarkers. We evaluated the prevalence and outcomes of 27 mutually exclusive CKD-MBD phenotypes in a large, multi-national cohort of chronic dialysis patients over a 5-year follow-up study. Methods In this historical cohort study, we enrolled all haemodialysis patients registered in EuCliD((R)) on 1 July 2011 across 28 Europe, the Middle East and Africa (EMEA) and South American countries. We created 27 mutually exclusive phenotypes based on combinations of serum parathyroid hormone (PTH), phosphorus (P) and calcium (Ca) 6-month averages (L, low ; T, target ; H, high). We tested the association between CKD- MBD phenotypes and 5-year mortality and hospitalization risk by outcome risk score- adjusted proportional hazard regression. Results We enrolled 35721 eligible patients. Eastern European and South American countries generally achieved poorer CKD-MBD control when compared with Western European countries (prevalence ratio: 0.79 ; P

Previously, we identified a potent antimicrobial analogue of temporin L (TL), [Pro3 ]TL, in which glutamine at position 3 was substituted with proline. In this study, a series of analogues in which position 3 is substituted with non-natural proline derivatives, was investigated for correlations between the conformational properties of the compounds and their antibacterial, cytotoxic, and hemolytic activities. Non-natural proline analogues with substituents at position 4 of the pyrrolidine ring were considered. Structure-activity relationship (SAR) studies of these analogues were performed by means of antimicrobial and cytotoxicity assays along with circular dichroism (CD) and NMR spectroscopic analyses for selected compounds. The most promising peptides were additionally evaluated for their activity against some representative veterinary microbial strains to compare with those from human strains. We identified novel analogues with interesting properties that make them attractive lead compounds.

We previously reported the discovery of a CXCL12-mimetic cyclic peptide (2) as a selective CXCR4 antagonist showing promising in vitro and in vivo anticancer activity. However, further development of this peptide was hampered by its degradation in biological fluids as well as by its low micromolar affinity for the receptor. Herein, extensive chemical modifications led to the development of a new analogue (10) with enhanced potency, specificity, and plasma stability. A combined approach of Ala-amino acid scan, NMR, and molecular modeling unraveled the reasons behind the improved binding properties of 10 vs 2. Biological investigations on leukemia (CEM) and colon (HT29 and HCT116) cancer cell lines showed that 10 is able to impair CXCL12-mediated cell migration, ERK-phosphorylation, and CXCR4 internalization. These outcomes might pave the way for the future preclinical development of 10 in CXCR4 overexpressing leukemia and colon cancer.

Background: Stroke prevention in dialysis-dependent patients with atrial fibrillation (AF) is an unresolved clinical dilemma. Indeed, no randomized controlled trial evaluating the efficacy and safety of oral anticoagulants in this population, has been conducted so far. Observational research on the use of warfarin in patients on dialysis has shown conflicting results. This uncertainty is mirrored by the wide variations in warfarin prescription patterns across centers. We sought to evaluate the association between the use of vitamin K antagonists (VKAs) and mortality among hemodialysis patient with AF and to assess potential factors affecting the risk-benefit profile of warfarin in this population. Methods: A total of 91,987 patients registered in the European Clinical Dialysis Database® system from January 2004 to January 2015. Of which, 9,238 patients were identified with a diagnosis of AF. After excluding ineligible patients, a 1:1 propensity score matched cohort of 1,324 warfarin users and non-users were assembled. Results: VKA use was associated with both increased 90-day survival (hazard ratio, HR 0.47, p < 0.01) and 6-year survival (HR 0.76, p < 0.01); however, a trend indicated a stronger early benefit (p for time-interaction Conclusion: VKA may provide an early survival benefit; however, this is partially offset later during the follow-up. In addition, heterogeneous risk-benefit profiles were observed among subgroups of dialysis-dependent patients with AF, further emphasizing the complexities of tailoring stroke prevention strategies in this population.

BACKGROUND Most of the studies on peripheral artery disease (PAD) focused on above-the-ankle artery disease, while less is known about foot artery disease. We hypothesize a scenario were two different diseases can be present in PAD patients, big artery disease (BAD) and small artery disease (SAD), overlapping at the foot level; the aim of this study is to evaluate their prevalence and their correlation with risk factors and critical limb ischemia (CLI) in a large cohort of patients with symptomatic PAD. METHODS We retrospectively reviewed 1915 limbs of 1613 patients (502 females, mean age 72.4±10.8 years) who underwent angiography between September 2009 and November 2013. Age, sex, diabetes, smoke history, high blood pressure, dialysis and BMI were considered as risk factors. Logistic regression was performed to test the association of arterial lesions patterns and CLI, and to evaluate the association between risk factors and lesion localization. RESULTS SAD was present in 414 patients (25.2%). Patients with disease of any of plantar, dorsalis pedis arteries and SAD faced higher risk of CLI (OR=13.25, 95% CI: 1.69-104.16). SAD was associated with diabetes and dialysis (both: OR=4.85; dialysis only: OR=3.60; diabetes only: OR=1.70; none: reference OR; P

Peptides-binding G protein-coupled receptors play an important role in many pathological and physiological pathways. The assessment of the receptor-bound conformation of a peptidic ligand within a membrane receptor such as a GPCR is of outmost importance for a rational drug design of more potent analogues. In this work, we applied multiple ligand-based NMR methods to study the interaction of peptide heptamers, derived from the C-X-C Motif Chemokine 12 (CXCL12), and the C-X-C Chemokine Receptor Type 4 (CXCR4) on membranes of human T-Leukemia cells (CCRF-CEM cells). To the best of our knowledge, this is the first structural study reporting the receptor-bound conformation of a peptide to a GPCR directly on a living cell. The results obtained in the field of CXCL12/CXCR4 are proofs of concept, although important information for researchers dealing with the CXCR4 field arise. General application of the presented NMR methodologies is possible and surely may help to accelerate the discovery of new therapeutic agents targeting GPCRs. Peptide-binding G protein-coupled receptors (GPCRs) are key effectors in numerous pathological and physiological pathways. The assessment of the receptor-bound conformation of a peptidic ligand within a membrane receptor such as a GPCR is of great impact for a rational drug design of more potent analogues. In this work, we applied multiple ligand-based nuclear magnetic resonance (NMR) methods to study the interaction of peptide heptamers, derived from the C-X-C Motif Chemokine 12 (CXCL12), and the C-X-C Chemokine Receptor Type 4 (CXCR4) on membranes of human T-Leukemia cells (CCRF-CEM cells). This study represents the first structural investigation reporting the receptor-bound conformation of a peptide to a GPCR directly on a living cell. The results obtained in the field of CXCL12/CXCR4 are proofs of concept, although important information for researchers dealing with the CXCR4 field arises. General application of the presented NMR methodologies is possible and surely may help to boost the development of new therapeutic agents targeting GPCRs.

The receptor for the urokinase-type plasminogen activator (uPAR) is a widely recognized master regulator of cell migration. We and others have previously documented that the uPAR(84–95) sequence, interacts with the formyl peptide receptors (FPR)s, henceforth inducing cell migration of several cell lines, including leukocytes, and the synthetic shorter peptide (Ser88-Arg-Ser-Arg-Tyr92, SRSRY) retains chemotactic activity in vitro and in vivo. Recently, we have developed the head-to-tail cyclic analog [SRSRY], a new potent and stable inhibitor of monocyte trafficking. This prompted us to develop novel cyclic and linear analogs of [SRSRY] with the aim to broaden the knowledge about structure-activity relationships of peptide [SRSRY]. Herein we report their synthesis, effects on cell migration, conformational and docking analyses which served to envisage a new pharmacophore model for inhibitors of FPR1-triggered cell migration.

In the fight against Glioblastoma Multiforme, recent literature data have highlighted that integrin alpha 5 beta 1 and p53 are part of convergent pathways in the control of glioma apoptosis. This observation prompted us to seek a molecule able to simultaneously modulate both target families. Analyzing the results of a previous virtual screening against murine double minute 2 protein (MDM2), we envisaged that Arg-Gly-Asp (RGD)-mimetic molecules could be inhibitors of MDM2/4. Herein, we present the discovery of compound 7, which inhibits both MDM2/4 and alpha 5 beta 1/alpha v beta 3 integrins. A lead optimization campaign was carried out on 7 with the aim to preserve the activities on integrins while improving those on MDM proteins. Compound 9 turned out to be a potent MDM2/4 and alpha 5 beta 1/alpha v beta 3 blocker. In p53 -wild type glioma cells, 9 arrested cell cycle and proliferation and strongly reduced cell invasiveness, emerging as the first molecule of a novel class of integrin/MDM inhibitors, which might be especially useful in subpopulations of patients with glioblastoma expressing a functional p53 concomitantly with a high level of alpha 5 beta 1 integrin.

Complementary and/or alternative safe substances, able to correct impaired lipid profile in humans, are still in great demand. The objective of the present work was to evaluate the in vitro and clinical effects of a novel nutraceutical product (AMD), formulated with Annurca apple polyphenolic extracts, on the intestinal cholesterol micellar solubility. AMD was able to decrease in vitro cholesterol micellar solubility by about 85.7%, while Nuclear Magnetic Resonance experiments allowed to hypothesize dimeric procyanidins as potential responsible compounds for this effect. Then, a randomised, double blind, single centre, placebo-controlled, crossover study, was designed to evaluate the effect of AMD on the fecal cholesterol excretion. Clinical data indicated that fecal cholesterol excretion was significantly increased (about +35%) in the AMD period compared with placebo period (P < 0.01). AMD may be regarded as a novel complementary and/or alternative safe remedy with clinical relevance in the primary cardiovascular disease prevention.

We report the development of macrocyclic melanocortin derivatives of MT-II and SHU-9119, achieved by modifying the cycle dimension and incorporating constrained amino acids in ring-closing. This study culminated in the discovery of novel agonists/antagonists with an unprecedented activity profile by adding pieces to the puzzle of the melanocortin receptor selectivity. Finally, the resulting 19- and 20-membered rings represent a suitable frame for the design of further therapeutic ligands as selective modulators of the melanocortin system.

The urotensin II receptor (UTR) has long been studied mainly for its involvement in the cardiovascular homeostasis both in health and disease state. Two endogenous ligands activate UTR, i.e. urotensin II (U-II) and urotensin II-related peptide (URP). Extensive expression of the two ligands uncovers the diversified pathophysiological effects mediated by the urotensinergic system such as cardiovascular disorders, smooth muscle cell proliferation, renal disease, diabetes, and tumour growth. As newly reported, U-II and URP have distinct effects on transcriptional activity, cell proliferation, and myocardial contractile activities supporting the idea that U-II and URP interact with UTR in a distinct manner (biased agonism). To shed light on the origin of the divergent activities of the two endogenous ligands, we performed a conformational study on URP by solution NMR in sodium dodecyl sulfate micelle solution and compared the obtained NMR structure of URP with that of hU-II previously determined. Finally, we undertook docking studies between URP, hU-II, and an UT receptor model. Copyright © 2015 European Peptide Society and John Wiley & Sons, Ltd.

In our ongoing pursuit of CXCR4 antagonists as potential anticancer agents, we recently developed a potent, selective and plasma stable peptide, Ac-Arg-Ala-[D-Cys-Arg-Phe-Phe-Cys]-COOH (3). Nevertheless, this compound was still not enough potent (IC50 ≈ 53 nM) to enter preclinical studies. Thus, a lead-optimization campaign was here undertaken to further improve the binding affinity of 3 while preserving its selectivity and proteolytic stability. Specifically, extensive structure-activity relationships (SARs) investigations were carried out on both its aromatic and disulfide forming amino acids. One among the synthesized analogue, Ac-Arg-Ala-[D-Cys-Arg-Phe-His-Pen]-COOH (19), displayed subnanomolar affinity towards CXCR4, with a marked selectivity over CXCR3 and CXCR7. NMR and molecular modeling studies disclosed the molecular bases for the binding of 19 to CXCR4 and for its improved potency compared to the lead 3. Finally, biological assays on specific cancer cell lines showed that 19 can impair CXCL12-mediated cell migration and CXCR4 internalization more efficiently than the clinically approved CXCR4 antagonist, plerixafor. In our ongoing pursuit of CXCR4 antagonists as potential anticancer agents, we recently developed a potent, selective, and plasma stable peptide, Ac-Arg-Ala-[D-Cys-Arg-Phe-Phe-Cys]-COOH (3). Nevertheless, this compound, was still not potent enough (IC50 approximate to 53 nM) to enter preclinical studies. Thus, a lead-optimization campaign was here undertaken to further improve the binding affinity of 3 while preserving its selectivity and proteolytic stability. Specifically, extensive structure activity relationships (SARs) investigations were carried out on both its aromatic and disulfide forming amino acids. One among the synthesized analogue, Ac-Arg-Ala-[D-Cys-Arg-Phe-His-Pen]-COOH (19), displayed subnanomolar affinity toward CXCR4, with a marked selectivity over CXCR3 and CXCR7. NMR and molecular modeling studies disclosed the molecular bases for the binding of 19 to CXCR4 and for its improved potency compared to the lead 3. Finally, biological assays on specific cancer cell lines showed that 19 can impair CXCL12-mediated cell migration and CXCR4 internalization more efficiently than the clinically approved CXCR4 antagonist plerixafor.

In this study we designed and synthesized a new library of antimicrobial peptides correlated to [Pro

The design of molecules that mimic biologically relevant glycans is a significant goal for understanding important biological processes and may lead to new therapeutic and diagnostic agents. In this study we focused our attention on the trisaccharide human natural killer cell-1 (HNK-1), considered the antigenic determinant of myelin-associated glycoprotein and the target of clinically relevant auto-antibodies in autoimmune neurological disorders such as IgM monoclonal gammopathy and demyelinating polyneuropathy. We describe a structure-activity relationship study based on surface plasmon resonance binding affinities aimed at the optimization of a peptide that mimics the HNK-1 minimal epitope. We developed a cyclic heptapeptide that shows an affinity of 1.09 x 10(-7) m for a commercial anti-HNK1 mouse monoclonal antibody. Detailed conformational analysis gave possible explanations for the good affinity displayed by this novel analogue, which was subsequently used as an immunological probe. However, preliminary screening indicates that patients' sera do not specifically recognize this peptide, showing that murine monoclonal antibodies cannot be used as a guide to select immunological probes for the detection of clinically relevant human auto-antibodies.