263 research outputs found

    Chitosan-cellulose Composite Materials: Preparation, Characterization and Application for Removal of Microcystin

    Get PDF
    We developed a simple and one-step method to prepare biocompatible composites from cellulose (CEL) and chitosan (CS). [BMIm+Cl−], an ionic liquid (IL), was used as a green solvent to dissolve and prepare the [CEL + CS] composites. Since majority (\u3e88%) of IL used was recovered for reuse by distilling the aqueous washings of [CEL + CS], the method is recyclable. XRD, FTIR, NIR, 13C CP-MAS-NMR and SEM were used to monitor the dissolution and to characterize the composites. The composite was found to have combined advantages of their components: superior mechanical strength (from CEL) and excellent adsorption capability for microcystin-LR, a deadly toxin produced by cyanobacteria (from CS). Specifically, the mechanical strength of the composites increased with CEL loading; e.g., up to 5× increase in tensile strength was achieved by adding 80% of CEL into CS. Kinetic results of adsorption confirm that unique properties of CS remain intact in the composite, i.e., it is not only a very good adsorbent for microcystin but also is better than all other available adsorbents. For example, it can adsorb 4× times more microcystin than the best reported adsorbent. Importantly, the microcystin adsorbed can be quantitatively desorbed to enable the composite to be reused with similar adsorption efficiency

    Protein Phosphatase 1 Beta is Modulated by Chronic Hypoxia and Involved in the Angiogenic Endothelial Cell Migration

    Get PDF
    Background/Aim: Endothelial cell migration is required for physiological angiogenesis, but also contributes to various pathological conditions, including tumour vascularization. The mRNA expression of PP1cβ, the beta isoform of the catalytic PP1 subunit, was shown to be upregulated in chronic hypoxia. Since hypoxia is a major regulator of angiogenesis, the potential role of PP1cβ in angiogenesis was investigated. Methods: We examined PP1cβ protein level in pediatric heart following chronic hypoxia and found PP1cβ upregulation in cyanotic compared with acyanotic myocardium. By treating HUVEC cells with hypoxia mimicking agent, PP1cβ protein level increased with maximum at 8 hours. The effect of PP1cβ pharmacological inhibition, knockdown and overexpression, on endothelial cell migration and morphogenesis, was examined using in vitro wound healing scratch assay and endothelial tube formation assay. The PP1cβ knockdown effects on F-actin reorganization (phalloidin staining), focal adhesion formation (vinculin) and focal adhesion kinases (FAK) activation, were evaluated by immunocytochemical staining and immunoblotting with specific antibodies. Results: PP1cβ knockdown significantly reduces endothelial cell migration, but does not have any significant effect on endothelial tube formation. Endothelial cell migration in the knockdown group is restored to the control level upon consecutive transfection with PP1cβ cDNA. PP1cβ overexpression does not significantly affect endothelial cell migration. Furthermore, PP1cβ knockdown induces profound cytoskeletal reorganization, loss of focal adhesion sites and impairment of focal adhesion kinases (FAK) activation. Conclusions: PP1cβ is regulator of endothelial cell migration, which is critical in the angiogenic process. PP1cβ inhibition reduces endothelial cell migration through focal adhesion turnover and actin polymerization pathways

    Outcome-based imitation in family firms’ international market entry decisions

    Get PDF
    This study examines the effects of family involvement on international market entry. Bridging theories of interorganizational imitation with the notion of socioemotional wealth protection, we argue that family-managed firms are more likely to act as “intuitive statisticians,” using the internationalization outcomes of industry peers to determine when to internationalize. An event history analysis of 2427 manufacturing firms supports this position. Family-managed firms’ likelihood to internationalize increases as prior entrants’ performance mean and variance increase. Ultimately, our study demonstrates that this imitation strategy enables family-managed firms to reduce risk and endure longer in broached international markets

    Neurocognition and social cognition in patients with schizophrenia spectrum disorders with and without a history of violence: results of a multinational European study

    Get PDF
    Objective: Neurocognitive impairment has been extensively studied in people with schizophrenia spectrum disorders and seems to be one of the major determinants of functional outcome in this clinical population. Data exploring the link between neuropsychological deficits and the risk of violence in schizophrenia has been more inconsistent. In this study, we analyse the differential predictive potential of neurocognition and social cognition to discriminate patients with schizophrenia spectrum disorders with and without a history of severe violence. Methods: Overall, 398 (221 cases and 177 controls) patients were recruited in forensic and general psychiatric settings across five European countries and assessed using a standardized battery. Results: Education and processing speed were the strongest discriminators between forensic and non-forensic patients, followed by emotion recognition. In particular, increased accuracy for anger recognition was the most distinctive feature of the forensic group. Conclusions: These results may have important clinical implications, suggesting potential enhancements of the assessment and treatment of patients with schizophrenia spectrum disorders with a history of violence, who may benefit from consideration of socio-cognitive skills commonly neglected in ordinary clinical practice

    Starch/Poly(glycerol-adipate) Nanocomposites: A Novel Oral Drug Delivery Device

    Get PDF
    © 2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).Biocompatible and bio-based materials are an appealing resource for the pharmaceutical industry. Poly(glycerol-adipate) (PGA) is a biocompatible and biodegradable polymer that can be used to produce self-assembled nanoparticles (NPs) able to encapsulate active ingredients, with encouraging perspectives for drug delivery purposes. Starch is a versatile, inexpensive, and abundant polysaccharide that can be effectively applied as a bio-scaffold for other molecules in order to enrich it with new appealing properties. In this work, the combination of PGA NPs and starch films proved to be a suitable biopolymeric matrix carrier for the controlled release preparation of hydrophobic drugs. Dynamic Light Scattering (DLS) was used to determine the size of drug-loaded PGA NPs, while the improvement of the apparent drug water solubility was assessed by UV-vis spectroscopy. In vitro biological assays were performed against cancer cell lines and bacteria strains to confirm that drug-loaded PGA NPs maintained the effective activity of the therapeutic agents. Dye-conjugated PGA was then exploited to track the NP release profile during the starch/PGA nanocomposite film digestion, which was assessed using digestion models mimicking physiological conditions. The collected data provide a clear indication of the suitability of our biodegradable carrier system for oral drug delivery.Peer reviewedFinal Published versio

    Integrin-linked kinase in muscle is necessary for the development of insulin resistance in diet-induced obese mice

    Get PDF
    Diet-induced muscle insulin resistance is associated with expansion of extracellular matrix (ECM) components, such as collagens, and the expression of collagen-binding integrin, α2β1. Integrins transduce signals from ECM via their cytoplasmic domains, which bind to intracellular integrin-binding proteins. The integrin-linked kinase (ILK)-PINCH-parvin (IPP) complex interacts with the cytoplasmic domain of β-integrin subunits and is critical for integrin signaling. In this study we defined the role of ILK, a key component of the IPP complex, in diet-induced muscle insulin resistance. Wild-type (ILK(lox/lox)) and muscle-specific ILK-deficient (ILK(lox/lox)HSAcre) mice were fed chow or a high-fat (HF) diet for 16 weeks. Body weight was not different between ILK(lox/lox) and ILK(lox/lox)HSAcre mice. However, HF-fed ILK(lox/lox)HSAcre mice had improved muscle insulin sensitivity relative to HF-fed ILK(lox/lox) mice, as shown by increased rates of glucose infusion, glucose disappearance, and muscle glucose uptake during a hyperinsulinemic-euglycemic clamp. Improved muscle insulin action in the HF-fed ILK(lox/lox)HSAcre mice was associated with increased insulin-stimulated phosphorylation of Akt and increased muscle capillarization. These results suggest that ILK expression in muscle is a critical component of diet-induced insulin resistance, which possibly acts by impairing insulin signaling and insulin perfusion through capillaries

    Sibling relationships and family functioning in siblings of early adolescents, adolescents and young adults with autism spectrum disorder

    Get PDF
    The purpose of the study was to investigate how family functioning (defined as the ability that family members hold to manage stressful events, and intimate and social relationships), the degree to which family members feel happy and fulfilled with each other (called family satisfaction), and the demographical characteristics of siblings (age and gender) impacted on sibling relationships. The Circumplex Model of Marital and Family Systems and Behavioral Systems constituted the theoretical frameworks that guided our study. Eighty-six typically developing adolescents and young adults having a sister or a brother with autism spectrum disorder were enrolled. Results indicated that the youngest age group (early adolescents) reported to engage more frequently in negative behaviors with their siblings with ASD than the two older age groups (middle adolescents and young adults). No significant differences were found among the three age groups regarding behaviors derived from attachment, caregiving and affiliative systems. Family satisfaction and age significantly predicted behaviors during sibling interactions. Suggestions on prevention and intervention programs were discussed in order to prevent parentification among typically developing siblings and decrease episodes of quarrels and overt conflicts between brothers and sisters with and without AS
    corecore