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Aim: Cell microenvironment contains a plethora of information that influences cell modulation. Indeed, the extracellular matrix plays a central role in tissue development. Reproducing the cell–extracellular matrix crosstalk able to recapitulate both physical and biochemical signals is crucial to obtain functional tissue models or regenerative strategies. Materials & methods: Here, a combined method is proposed to easily functionalize collagen surface films, tailoring morphological properties. Oxygen nonthermal plasma treatment and glyco-conjugation with chondroitin sulfate are used to modify surface properties. Results: It results in higher adhesion, proliferation and morphological organization of U87 glioblastoma cells. Conclusion: Our finding suggests new promising strategies for the development of collagen-based biomaterials, which can be employed for advanced in vitro models.

OBJECTIVES: The purpose of this study was to evaluate the impact of a polyphenols-based treatment on the extrinsic mechanisms responsible for early bioprosthetic heart valve (BHV) degeneration. Structural degeneration can be driven by both extrinsic and intrinsic mechanisms. While intrinsic mechanisms have been associated with inherent biocompatibility characteristics of the BHV, the extrinsic ones have been reported to involve external causes, such as chemical, mechanical and hydrodynamic, responsible to facilitate graft damage. METHODS: The chemical interaction and the stability degree between polyphenols and pericardial tissue were carefully evaluated. The detoxification of glutaraldehyde in commercial BHVs models and the protective effect from in vivo calcification were taken into relevant consideration. Finally, the hydrodynamic and biomechanical features of the polyphenols-treated pericardial tissue were deeply investigated by pulse duplicator and stress-strain analysis. RESULTS: The study demonstrated the durability of the polyphenols-based treatment on pericardial tissue and the stability of the bound polyphenols. The treatment improves glutaraldehyde stabilization’s current degree, demonstrating a surprising in vivo anti-calcific effect. It is able to make the pericardial tissue more pliable while maintaining the correct hydrodynamic characteristics. CONCLUSIONS: The polyphenols treatment has proved to be a promising approach capable of acting simultaneously on several factors related to the premature degeneration of cardiac valve substitutes by extrinsic mechanisms.

The development of new advanced constructs resembling structural and functional properties of human organs and tissues requires a deep knowledge of the morphological and biochemical properties of the extracellular matrices (ECM), and the capacity to reproduce them. Manufacturing technologies like 3D printing and bioprinting represent valuable tools for this purpose. This review will describe how morphological and biochemical properties of ECM change in different tissues, organs, healthy and pathological states, and how ECM mimics with the required properties can be generated by 3D printing and bioprinting. The review describes and classifies the polymeric materials of natural and synthetic origin exploited to generate the hydrogels acting as "inks" in the 3D printing process, with particular emphasis on their functionalization allowing crosslinking and conjugation with signaling molecules to develop bio-responsive and bio-instructive ECM mimics.

Alginate–gelatin hydrogels mimicking extracellular matrix (ECM) of soft tissues have been generated by static–dynamic double crosslinking, allowing fine control over the physical and chemical properties. Dynamic crosslinking provides self-healing and injectability attributes to the hydrogel and promotes cell migration and proliferation, while the static network improves stability. The static crosslinking was performed by enzymatic coupling of the tyrosine residues of gelatin with tyramine residues inserted in the alginate backbone, catalyzed by horseradish peroxidase (HRP). The dynamic crosslinking was obtained by functionalizing alginate with 3-aminophenylboronic acid which generates a reversible bond with the vicinal hydroxyl groups of the alginate chains. Varying the ratio of alginate and gelatin, hydrogels with different properties were obtained, and the most suitable for 3D soft tissue model development with a 2.5:1 alginate:gelatin molar ratio was selected. The selected hydrogel was characterized with a swelling test, rheology test, self-healing test and by cytotoxicity, and the formulation resulted in transparent, reproducible, varying biomaterial batch, with a fast gelation time and cell biocompatibility. It is able to modulate the loss of the inner structure stability for a longer time with respect to the formulation made with only covalent enzymatic crosslinking, and shows self-healing properties.

In cancer microenvironment, aberrant glycosylation events of ECM proteins and cell surface receptors occur. We developed a protocol to generate 3D bioprinted models of colorectal cancer (CRC) crosslinking hyaluronic acid and gelatin functionalized with three signalling glycans characterized in CRC, 3′-Sialylgalactose, 6′-Sialylgalactose and 2′-Fucosylgalactose. The crosslinking, performed exploiting azide functionalized gelatin and hyaluronic acid and 4arm-PEG-dibenzocyclooctyne, resulted in biocompatible hydrogels that were 3D bioprinted with commercial CRC cells HT-29 and patient derived CRC tumoroids. The glycosylated hydrogels showed good 3D printability, biocompatibility and stability over the time. SEM and synchrotron radiation SAXS/WAXS analysis revealed the influence of glycosylation in the construct morphology, whereas MALDI-MS imaging showed that protein profiles of tumoroid cells vary with glycosylation, indicating that sialylation and fucosylation of ECM proteins induce diverse alterations to the proteome of the tumoroid and surrounding cells.

A protocol based on the combination of different analytical methodologies is proposed to standardize the experimental conditions for reproducible formulations of hybrid hydrogels. The final hybrid material, based on the combination of gelatin and chitosan functionalized with methylfuran and cross-linked with 4-arm-PEG-maleimide, is able to mimic role, dynamism, and structural complexity of the extracellular matrix. Physical–chemical properties of starting polymers and finals constructs were characterized exploiting the combination of HP-SEC-TDA, UV, FT-IR, NMR, and TGA.

The Diels–Alder (DA) cycloaddition is one of the best methods for biomaterials conjugation to generate tools for biomedical applications. It is a biocompatible one-step reaction, exploiting functional groups absent in natural biopolymers, doesn't require catalysts, and doesn't generate side products, an ideal “click reaction”. In this review we provide an overview on the recent examples in which the DA cycloaddition has been exploited in nanomedicine. Nanoparticles for drug delivery or diagnosis, and nanostructured biomaterials for regenerative medicine, have been efficiently generated exploiting the DA reaction to crosslink the polymeric components, in order to obtain nanoparticles or scaffolds with the required chemical and morphological properties, and to conjugate targeting agents or signalling molecules.

This recommendation proposes a definition for the term "chalcogen bond"; it is recommended the term is used to designate the specific subset of inter- A nd intramolecular interactions formed by chalcogen atoms wherein the Group 16 element is the electrophilic site.

The peculiarity of glycans expressed in humans, in both physiologic and pathologic state, and in pathogenic organisms, is unveiling precious information useful for the early detection of cancers, acute and chronic inflammatory states and infections. Indeed, the glycocode dynamism and the wide range of functions covered by glycans are pivotal in the development of the most recent pioneering and effective nanoprobes eligible as ultrasensitive biosensors for multiple diseases, strongly impacting on clinical diagnostic strategies. In this report, the current, forthcoming and potential diagnostic use of glycans, in combination with advanced nanomaterials, is discussed.

Cell microenvironments are able to induce cell fate, resulting in tissue regeneration or in pathological events. The development of artificial ECMs, the main component of cell microenvironments, provides invaluable tools in regenerative medicine. Glycans are indispensable components of ECMs, to which they provide not only structural and mechanical properties, but also biological signals. In this chapter we describe the strategies to generate artificial 3D ECMs, exploiting both glycans and proteins, modulating the structure, morphology and signalling content able to induce specific cell fates. The functionalization approaches to conjugate biomaterials with glycidic cues and to crosslink polysaccharide to proteins or synthetic polymers are described. The role of glycans to induce specific cell fate is analysed in the relatively few examples reported in the literature.

The development of 3D printable hydrogels based on the crosslinking between chitosan and gelatin is proposed. Chitosan and gelatin were both functionalized with methyl furan groups. Chemical modification was performed by reductive amination with methyl furfural involving the lysine residues of gelatin and the amino groups of chitosan to generate hydrogels with tailored properties. The methyl furan residues present in both polymers were exploited for efficient crosslinking via Diels-Alder ligation with PEG-Star-maleimide under cell-compatible conditions. The obtained chitosan-gelatin hybrid was employed to formulate hydrogels and 3D printable biopolymers and its processability and biocompatibility were preliminarily investigated.

Synthetic 3D extracellular matrices (ECMs) find application in cell studies, regenerative medicine, and drug discovery. While cells cultured in a monolayer may exhibit unnatural behavior and develop very different phenotypes and genotypes than in vivo, great efforts in materials chemistry have been devoted to reproducing in vitro behavior in in vivo cell microenvironments. This requires fine-tuning the biochemical and structural actors in synthetic ECMs. This review will present the fundamentals of the ECM, cover the chemical and structural features of the scaffolds used to generate ECM mimics, discuss the nature of the signaling biomolecules required and exploited to generate bioresponsive cell microenvironments able to induce a specific cell fate, and highlight the synthetic strategies involved in creating functional 3D ECM mimics.

By functionalizing the surface of PEG-liposomes with linkers bearing quaternary ammonium compounds (QACs), we generated novel bacteria disruptors with anti-adhesive properties and reduced cytotoxicity compared to free QACs. Furthermore, QAC-functionalized liposomes are a promising platform for future drug encapsulation. The QAC (11-mercaptoundecyl)-N,N,N-trimethylammonium bromide (MTAB) was attached to maleimide-functionalized liposomes (DSPE-PEG) via thiol linker. The MTAB-functionalized liposomes were physicochemically characterized and their biological activity, in terms of anti-adherence activity and biofilm prevention in Escherichia coli were assessed. The results showed that MTAB-functionalized liposomes inhibit bacterial adherence and biofilm formation while reducing MTAB toxicity.

The key signalling roles played by glycans (simple or complex) in the development of smart biomaterials for neuroregeneration is reported. The glycans involved and their diversity (glycomic), the nature and properties of biomaterials, the bioconjugation methods, and the effects in neuroregeneration are discussed.

The cell microenvironment plays a pivotal role in mediating cell adhesion, survival, and proliferation in physiological and pathological states. The relevance of extracellular matrix (ECM) proteins in cell fate control is an important issue to take into consideration for both tissue engineering and cell biology studies. The glycosylation of ECM proteins remains, however, largely unexplored. In order to investigate the physio-pathological effects of differential ECM glycosylation, the design of affordable chemoselective methods for ECM components glycosylation is desirable. We will describe a new chemoselective glycosylation approach exploitable in aqueous media and on non-protected substrates, allowing rapid access to glyco-functionalized biomaterials.

Glycans have been selected by nature for both structural and 'recognition' purposes. Taking inspiration from nature, nanomedicine exploits glycans not only as structural constituents of nanoparticles and nanostructured biomaterials but also as selective interactors of such glyco-nanotools. Surface glycosylation of nanoparticles finds application in targeting specific cells, whereas recent findings give evidence that the glycan content of cell microenvironment is able to induce the cell fate. This review will highlight the role of glycans in nanomedicine, schematizing the different uses and roles in drug-delivery systems and in biomaterials for regenerative medicine.

Phage display is a powerful and widely used technique to find novel peptide ligands. A massive amount of peptide sequences have been identified for all kinds of materials, and peptides that may have targeting capabilities towards specific cells and tissues have received special attention in biomedical sciences. As a result, it is increasingly harder to follow all the work that has been done, which sometimes leads to many promising ligands receiving little attention, together with the publication of false positives that have already been found. The aim of this review is to provide an updated and comprehensive list of phage-displayed peptides targeting different tissues and organs. The limitations of the technique are carefully analysed and the future perspectives envisaged.

Purpose: The effect of drug exposure misclassification generally receives little attention in pharmacoepidemiological research. In this paper, we illustrate a probabilistic bias analysis approach for misclassified categorical exposures and apply it in a database study of oral anti-hyperglycaemic drugs (OADs). Methods: A cohort study based on the Health Search Database general-practice database was carried out by including 12 640 adult (≥40 years) patients newly treated with OADs during 2003–2010. The proportion of days covered by OADs prescriptions during the first year of follow-up was evaluated for each individual, either by means of the prescribed daily dose or the defined daily dose. The effect of misclassification on hypothetical OAD–outcome association profiles was assessed through the proposed probabilistic bias analysis approach, taking advantage of available exposure validation data. Results: During the first year of follow-up, the average (SD) number of months with OADs available was 7 (4) months and 5 (3) months according to the prescribed daily dose and defined daily dose metrics, respectively. Probabilistic bias analysis results based on validation data suggest that the effect of misclassification is complex, as conventional exposure–outcome association estimates may be of greater or lower magnitude than their misclassification-adjusted values. Conclusions: Misclassification should be taken into account in database studies on the safety of prescribed medications. To this aim, investigators should take advantage of external exposure validation data in sensitivity analysis approaches such as ours. Copyright © 2016 John Wiley & Sons, Ltd.

Incidence, predictors and effect of discontinuation of long-acting bronchodilators on the risk of death or hospital admission among adults with Chronic Obstructive Pulmonary Disease (COPD) were assessed in a large population-based prospective study carried out by linking Italian healthcare utilization databases. Specifically, the cohort of 17,490 beneficiaries of the National Health Service in the Italian Region of Lombardy, aged 40 years or older, who started long-acting bronchodilators therapy during 2005–2008 was followed from first dispensation until 2012. During this period, patients who experienced discontinuation of long-acting bronchodilators were identified. Hospitalizations for COPD and deaths for any cause (composite clinical outcome) were also identified during follow-up. A Cox proportional hazards model was fitted to identify predictors of discontinuation. The case-crossover design was used to assess the implications of treatment discontinuation on the clinical outcome risk. Cumulative incidences of discontinuation were, respectively, 67%, 80%, and 92% at 6 months, 1 year, and 5 years since initial treatment. Significant predictors of discontinuation were female gender, younger age, starting treatment with fixed-dose combination of inhaled bronchodilators and corticosteroids, using antibiotics, inhaled long-acting bronchodilators and corticosteroids and not using short-acting bronchodilators, other respiratory drugs and systemic corticosteroids during follow-up. Odds ratios (95% confidence intervals) for the clinical outcome associated with not discontinuing long-acting bronchodilators was 0.64 (0.50 to 0.82). In conclusion, in the real-life setting, discontinuation of inhaled long-acting bronchodilators in adults with COPD is high even after just 6 months, even though persistence to these drugs reduces the risk of severe outcomes.

Metformin may reduce the risk of endometrial cancer whereas other drugs for the treatment of type 2 diabetes mellitus appear to increase it, although the evidence is still limited. We investigated this issue using data from a nested case-control study within the healthcare utilization databases of the Lombardy Region, Italy. This study included 376 diabetic women with endometrial cancer and 7485 diabetic controls matched for cases on age, date at cohort entry, and duration of follow-up. We used conditional logistic regression models to estimate the odds ratio (OR) of endometrial cancer in relation to use of antidiabetic drugs, adjusted for the Charlson's comorbidity index, selected medical conditions, prescription of selected drugs, and concomitant use of other antidiabetic drugs. At cohort entry, no significant associations were observed for metformin [OR=0.99, 95% confidence interval (CI) 0.80-1.23], sulfonylureas (OR=1.14, 95% CI 0.91-1.42), insulin (OR=0.72, 95% CI 0.34-1.56), and other antidiabetic drugs (OR=1.21, 95% CI 0.75-1.95). When we considered use during follow-up, a borderline significant excess risk was found for metformin (OR=1.30, 95% CI 1.00-1.70). However, this estimate decreased to 1.07 (95% CI 0.82-1.41) when taking into account BMI using a Monte Carlo sensitivity analysis. No significant associations were found for sulfonylureas (OR=1.16, 95% CI 0.91-1.47), thiazolidinediones (OR=0.77, 95% CI 0.48-1.24), repaglinide (OR=1.32, 95% CI 0.94-1.87), incretins (OR=1.21, 95% CI 0.63-2.32), and insulin (OR=1.19, 95% CI 0.82-1.71). Our data indicate that metformin, insulin, and other antidiabetic drugs did not meaningfully affect the risk of endometrial cancer.

OBJECTIVES: To investigate the cardiovascular safety of non-steroidal anti-inflammatory drugs (NSAIDs) and estimate the risk of hospital admission for heart failure with use of individual NSAIDs.DESIGN: Nested case-control study.SETTING: Five population based healthcare databases from four European countries (the Netherlands, Italy, Germany, and the United Kingdom).PARTICIPANTS: Adult individuals (age ≥18 years) who started NSAID treatment in 2000-10. Overall, 92 163 hospital admissions for heart failure were identified and matched with 8 246 403 controls (matched via risk set sampling according to age, sex, year of cohort entry).MAIN OUTCOME MEASURE: Association between risk of hospital admission for heart failure and use of 27 individual NSAIDs, including 23 traditional NSAIDs and four selective COX 2 inhibitors. Associations were assessed by multivariable conditional logistic regression models. The dose-response relation between NSAID use and heart failure risk was also assessed.RESULTS: Current use of any NSAID (use in preceding 14 days) was found to be associated with a 19% increase of risk of hospital admission for heart failure (adjusted odds ratio 1.19; 95% confidence interval 1.17 to 1.22), compared with past use of any NSAIDs (use >183 days in the past). Risk of admission for heart failure increased for seven traditional NSAIDs (diclofenac, ibuprofen, indomethacin, ketorolac, naproxen, nimesulide, and piroxicam) and two COX 2 inhibitors (etoricoxib and rofecoxib). Odds ratios ranged from 1.16 (95% confidence interval 1.07 to 1.27) for naproxen to 1.83 (1.66 to 2.02) for ketorolac. Risk of heart failure doubled for diclofenac, etoricoxib, indomethacin, piroxicam, and rofecoxib used at very high doses (≥2 defined daily dose equivalents), although some confidence intervals were wide. Even medium doses (0.9-1.2 defined daily dose equivalents) of indomethacin and etoricoxib were associated with increased risk. There was no evidence that celecoxib increased the

Cancer cells often rely on glycolysis to obtain energy and support anabolic growth. Several studies showed that glycolytic cells are susceptible to cell death when subjected to low glucose availability or to lack of glucose. However, some cancer cells, including glycolytic ones, can efficiently acquire higher tolerance to glucose depletion, leading to their survival and aggressiveness. Although increased resistance to glucose starvation has been shown to be a consequence of signaling pathways and compensatory metabolic routes activation, the full repertoire of the underlying molecular alterations remain elusive. Using omics and computational analyses, we found that cyclic adenosine monophosphate-Protein Kinase A (cAMP-PKA) axis activation is fundamental for cancer cell resistance to glucose starvation and anoikis. Notably, here we show that such a PKA-dependent survival is mediated by parallel activation of autophagy and glutamine utilization that in concert concur to attenuate the endoplasmic reticulum (ER) stress and to sustain cell anabolism. Indeed, the inhibition of PKA-mediated autophagy or glutamine metabolism increased the level of cell death, suggesting that the induction of autophagy and metabolic rewiring by PKA is important for cancer cellular survival under glucose starvation. Importantly, both processes actively participate to cancer cell survival mediated by suspension-activated PKA as well. In addition we identify also a PKA/Src mechanism capable to protect cancer cells from anoikis. Our results reveal for the first time the role of the versatile PKA in cancer cells survival under chronic glucose starvation and anoikis and may be a novel potential target for cancer treatment.

Background and objective: Real-world evidence suggests that persistence with inhaled corticosteroids (ICS), the mainstay of asthma drug therapy, is generally poor. The effect of persistence with ICS on the risk of asthma exacerbation was addressed in a population-based study. Methods: The cohort of 2335 beneficiaries of the National Health Service provided by the Italian Region of Lombardy, aged 18–40 years and newly treated with ICS during 2005–2008, was followed from their first ICS dispensation until 2010. Discontinuation of treatment with ICS and starting oral corticosteroid therapy during follow-up were respectively regarded as proxies of poor persistence with asthma medication and asthma exacerbation (outcomes). A proportional hazards model was fitted to identify predictors of ICS discontinuation. Case-crossover and case-case-time-control designs and conditional logistic regressions were used to estimate the association between persistence with ICS and asthma exacerbation. Results: Cumulative incidences of discontinuation were 36%, 57% and 78% at 6 months, 1 year and 5 years, respectively. Predictors of poor persistence were female gender, use of antibiotics during follow-up, absence of use of short-acting beta-agonists prior to and after starting treatment with ICS and starting and maintaining ICS monotherapy during follow-up. The odds ratios of asthma exacerbation (and 95% confidence intervals) associated with ICS exposure during the current period, contrasted with exposure during the reference period, were 0.4 (0.2, 0.9) and 0.3 (0.1, 1.0) from case-crossover and case-case-time-control estimates, respectively. Conclusion: Persistence with ICS treatment in adults with asthma reduces the risk of exacerbation in the real-life setting.

A new hydrogel, totally based on gelatin has been synthesized by cross-linking thiolated gelatin with pentenoyl gelatin, via thiol-ene click chemistry. Preliminary cytocompatibility assays with hBMSC showed good cell compatibility.

D-Glucose derivatives bearing an anomeric thiophenyl group and orthogonally protections on secondary hydroxyl groups were linked to solid supports (PS/DV polymer, tentagel resin) through an ester bond on C-6. It was investigated the possibility to remove orthogonally protecting groups and functionalize selectively the free hydroxyls groups and the anomeric carbon of sugars in solid phase