Silk nanoparticles: from inert supports to bioactive natural carriers for drug delivery.

Silk proteins have been studied and employed for the production of drug delivery (nano)systems. They show excellent biocompatibility, controllable biodegradability and non-immunogenicity and, if needed, their properties can be modulated by blending with other polymers. Silk fibroin (SF), which forms the inner core of silk, is a (bio)material officially recognized by the Food and Drug Administration for human applications. Conversely, the potential of silk sericin (SS), which forms the external shell of silk, could still be considered under evaluation. At the best of our knowledge, nanoparticles based on silk sericin "alone" cannot be produced, due to its physicochemical instability influenced by extreme pH, high water solubility and temperature; for these reasons, it almost always needs to be combined with other polymers for the development of drug delivery systems. In this review, we focused on silk proteins as bioactive natural carriers, since they show not only optimal features as inert excipients, but also remarkable intrinsic biological activities. SF has anti-inflammatory properties, while SS presents antioxidant, anti-tyrosine, anti-aging, anti-elastase and anti-bacterial features. Here, we give an overview on SF or SS silk-based nanosystems, with particular attention on the production techniques.

Substance use disorders in hospitalized psychiatric patients: the experience of one psychiatric emergency service in Turin.

In the present study we sought: 1) to estimate the frequency of substance use disorders (SUD), and 2) to investigate whether there is a mere association between diagnosis and SUD in a large cohort of patients with severe psychiatric disorders representative of the usual setting and modality of care of a psychiatric emergency service in a geographically well-defined catchment area in Italy, independent of sociodemographic features, anamnestic data and clinical status. The study was conducted between January 2007 and December 2008. The following rating scales were performed: the Clinical Global Impression-Severity (CGI-S), the Global Assessment of Functioning scale (GAF) and the Brief Psychiatric Rating Scale (BPRS). Factors found to be associated (p<0.05) with SUD[+] in the univariate analyses were subjected to multilevel logistic regression model with a backward stepwise procedure. Among 848 inpatients of our sample 29.1% had a SUD codiagnosis. Eleven factors accounted for 30.6% of the variability in SUD[+]: [a] a Personality Disorder diagnosis, [b] a Depressive Disorder diagnosis, [c] male gender, [d] previous outpatient contacts, [e] single marital status, [f] no previous psychiatric treatments, [g] younger age, [h] lower scores for BPRS Anxiety-depression and [i] BPRS Thought Disturbance, [l] higher scores for BPRS Activation and [m] BPRS Hostile-suspiciousness. The findings are important in identifying (1) the complexity of the clinical presentation of SUD in a inpatients sample, (2) the need for collaboration among health care workers, and (3) the need to develop and apply treatment programs that are targeted at particular risk groups.

Differential diagnosis between schizophrenia and autism in adulthood: a case report.

The clinical distinction between autism spectrum disorders (ASD), also called pervasive developmental disorders (PDD), and schizophrenia is often difficult to make. Here we describe a case of an adult patient presenting with a diagnosis of schizophrenia based on a history of functional deterioration and presumed persecutory delusions. A psychiatric and psychological assessment conducted from a developmental perspective, in association with direct observation and neuropsychological evaluation for intellectual disabilities and autism, led to a diagnosis of PDD not otherwise specified, with revision of the initial diagnosis of schizophrenia.

Cognitive function and competitive employment in schizophrenia: relative contribution of insight and psychopathology.

PURPOSE: This study investigated the relationships among insight, psychopathology, cognitive function, and competitive employment in order to determine whether insight and/or psychopathology carried the influence of cognitive function to competitive employment. METHODS: We recruited 253 outpatients with stable schizophrenia and we further divided our sample into two groups of patients (unemployed and competitive employment subjects). Clinical and neuropsychological assessments were performed. All clinical variables significantly different between the two groups of subjects were subsequently analyzed using a binary logistic regression to assess their independent contribution to competitive employment in the two patients' groups. On the basis of the regression results two mediation analyses were performed. RESULTS: Verbal memory, general psychopathology, and awareness of mental illness were significantly associated with competitive employment in our sample. Both awareness of mental illness and general psychopathology had a role in mediating the verbal memory-competitive employment relationship. CONCLUSIONS: Taken together, these findings confirmed the importance of cognitive function in obtaining competitive employment. Our results also highlighted the independent role of general psychopathology and awareness of illness on occupational functioning in schizophrenia. Thus, a greater attention must be given to the systematic investigation of insight and general psychopathology in light of an amelioration of vocational functioning in stable schizophrenia.

Silk fibroin nanoparticles for celecoxib and curcumin delivery: ROS-scavenging and anti-inflammatory activities in an in vitro model of osteoarthritis.

This paper aims at demonstrating silk fibroin nanoparticles (SFNs) promote anti-inflammatory properties of celecoxib (CXB) or curcumin (CUR), and could be exploited for osteoarthritis (OA) treatment. Nanoparticles were prepared by desolvation method and physico-chemically characterized (FT-IR, DSC, TGA, SEM, size distribution and drug release); empty and drug loaded nanoparticles were tested for their ROS-scavenging activity, hemolytic properties, cytotoxicity, and anti-inflammatory potency in an OA in vitro model. Results indicate that a controlled drug release has been achieved by varying the drug loading. Curcumin plus SFNs exhibited a synergistic antioxidant effect, while CXB was, in some manner, inhibitory. Both free drugs resulted highly cytotoxic while cell viability reached high values when encapsulated in SFNs. No appreciable differences in anti-inflammatory activity was evidenced between CUR loaded SFNs and CXB. In conclusion, SFNs is an optimal carrier to improve cyto- and hemo-compatibility of both CUR and CXB.

In Vitro Effectiveness of Microspheres Based on Silk Sericin and Chlorella vulgaris or Arthrospira platensis for Wound Healing Applications.

Some natural compounds have recently been widely employed in wound healing applications due to their biological properties. One such compound is sericin, which is produced by Bombix mori, while active polyphenols, polysaccharides and proteins are synthetized by Chlorella vulgaris and Arthrospira platensis microalgae. Our hypothesis was that sericin, as an optimal bioactive polymeric carrier for microencapsulation process, could also improve the regenerative effect of the microalgae. A solvent-free extraction method and spray drying technique were combined to obtain five formulations, based on algal extracts (C. vulgaris and A. platensis, Chl and Art, respectively) or silk sericin (Ser) or their mixtures (Chl-Ser and Art-Ser). The spray drying was a suitable method to produce microspheres with similar dimensions, characterized by collapsed morphology with a rough surface. Art and Art-Ser showed higher antioxidant properties than other formulations. All microspheres resulted in cytocompatibility on fibroblasts until 1.25 mg/mL and promoted cell migration and the complete wound closure; this positive effect was further highlighted after treatment with Art and Art-Ser. To our surprize the combination of sericin to Art did not improve the microalgae extract efficacy, at least in our experimental conditions.

Mesenchymal stem/stromal cell extracellular vesicles: From active principle to next generation drug delivery system.

It has been demonstrated that the biological effector of mesenchymal stem/stromal cells (MSCs) is their secretome, which is composed of a heterogeneous pool of bioactive molecules, partially enclosed in extracellular vesicles (EVs). Therefore, the MSC secretome (including EVs) has been recently proposed as possible alternative to MSC therapy. The secretome can be considered as a protein-based biotechnological product, it is probably safer compared with living/cycling cells, it presents virtually lower tumorigenic risk, and it can be handled, stored and sterilized as an Active Pharmaceutical/Principle Ingredient (API). EVs retain some structural and technological analogies with synthetic drug delivery systems (DDS), even if their potential clinical application is also limited by the absence of reproducible/scalable isolation methods and Good Manufacturing Practice (GMP)-compliant procedures. Notably, EVs secreted by MSCs preserve some of their parental cell features such as homing, immunomodulatory and regenerative potential. This review focuses on MSCs and their EVs as APIs, as well as DDS, considering their ability to reach inflamed and damaged tissues and to prolong the release of encapsulated drugs. Special attention is devoted to the illustration of innovative therapeutic approaches in which nanomedicine is successfully combined with stem cell therapy, thus creating a novel class of "next generation drug delivery systems."

Stem cell-extracellular vesicles as drug delivery systems: New frontiers for silk/curcumin nanoparticles.

The aim of this work was to develop a novel carrier-in-carrier system based on stem cell-extracellular vesicles loaded of silk/curcumin nanoparticles by endogenous technique. Silk nanoparticles were produced by desolvation method and curcumin has been selected as drug model because of its limited water solubility and poor bioavailability. Nanoparticles were stable, with spherical geometry, 100nm in average diameter and the drug content reached about 30%. Cellular uptake studies, performed on mesenchymal stem cells (MSCs), showed the accumulation of nanoparticles in the cytosol around the nuclear membrane, without cytotoxic effects. Finally, MSCs were able to release extracellular vesicles entrapping silk/curcumin nanoparticles. This combined biological-technological approach represents a novel class of nanosystems, combining beneficial effects of both regenerative cell therapies and pharmaceutical nanomedicine, avoiding the use of viable replicating stem cells.

Stromal Vascular Fraction Loaded Silk Fibroin Mats Effectively Support the Survival of Diabetic Mice after Pancreatic Islet Transplantation.

The aim of this study is to assess whether stromal vascular fraction (SVF)-soaked silk fibroin nonwoven mats (silk-SVF) can preserve the functionality of encapsulated pancreatic endocrine cells (alginate-PECs) after transplantation in the subcutaneous tissue of diabetic mice. Silk scaffolds are selected to create an effective 3D microenvironment for SVF delivery in the subcutaneous tissue before diabetes induction: silk-SVF is subcutaneously implanted in the dorsal area of five healthy animals; after 15 d, mice are treated with streptozotocin to induce diabetes and then alginate-PECs are implanted on the silk-SVF. All animals appear in good health, increasing weight during time, and among them, one presents euglycemia until the end of experiments. On the contrary, when PECs are simultaneously implanted with SVF after diabetes induction, mice are euthanized due to suffering. This work clearly demonstrates that silk-SVF creates a functional niche in subcutaneous tissue and preserves endocrine cell survival and engraftment.

Alginate encapsulation preserves the quality and fertilizing ability of Mediterranean Italian water buffalo (Bubalus bubalis) and Holstein Friesian (Bos taurus) spermatozoa after cryopreservation.

The use of artificial insemination (AI) in buffalo (Bubalus bubalis) is limited by poor ovarian activity during the hot season, seasonal qualitative patterns in semen, low resistance of sperm cells in the female tract, difficulties in estrus detection, and variable estrus duration. Although AI procedures are commonly used in bovine, use of AI has been limited in buffalo. In the zootechnical field, different studies have been conducted to develop techniques for improvement of fertilizing ability of buffalo spermatozoa after AI. In this study, for the first time, the use of alginate encapsulation and cryopreservation of buffalo spermatozoa is described, and the same procedure was performed with Holstein Friesian (Bos taurus) semen. Results obtained from in vitro analyses indicate that the encapsulation process does not have detrimental effects (compared to controls) on quality parameters (membrane integrity, progressive motility, path average velocity) in either species. Similarly, there were no detrimental effects after cryopreservation in either species. The fertilizing potential of encapsulated and cryopreserved semen was evaluated after AI in 25 buffalo and 113 bovine females. Pregnancy rates were not affected in either species. The results of this study show proof of concept for the use of frozen semen controlled-release devices in buffalo.

Relative contributions of negative symptoms, insight, and coping strategies to quality of life in stable schizophrenia.

The purpose of this cross-sectional study was to examine the relative contributions of negative symptomatology, insight, and coping to quality of life (QOL) in a sample of 92 consecutive outpatients with stable schizophrenia referring to the Department of Neuroscience, Psychiatric Section, University of Turin, Struttura Semplice di Coordinamento a Valenza Dipartimentale (SSCVD), Department of Mental Health ASL TO1, Molinette, Italy, in the period between July 2009 and July 2011. In order to assess the specific effect of negative symptoms on QOL and the possible mediating role of insight and coping, two mediation hypotheses were tested, using multiple regression analyses specified by Baron and Kenny (1986). Our findings suggest that (a) higher negative symptoms predict a worse Quality of Life Scale (QLS) intrapsychic foundations (IF) subscale score; (b) attribution of symptoms and coping-social diversion have a direct and positive association with QLS-IF; (c) patients high in negative symptoms are less likely to use attribution of symptoms and coping-social diversion; and (d) attribution of symptoms and coping-social diversion act as partial mediators in the negative symptoms-QOL relationship. The prediction model accounts for 45.3% of the variance of the QLS-IF subscale score in our sample. In conclusion, our results suggest that insight and coping-social diversion substantially contribute to QOL in patients with higher negative symptoms. These factors are potentially modifiable from specific therapeutic interventions, which can produce considerable improvements in the QOL of this population.

Cognitive functioning and insight in schizophrenia and in schizoaffective disorder.

AIM: The aim of this study was to investigate cognitive functioning and insight of illness in two groups of patients during their stable phases, one with schizophrenia and one with schizoaffective disorder. METHODS: We recruited 104 consecutive outpatients, 64 with schizophrenia, 40 with schizoaffective disorder, in the period between July 2010 and July 2011. They all fulfilled formal Diagnostic and Statistical Manual of Mental disorders (DSM-IV-TR) diagnostic criteria for schizophrenia and schizoaffective disorder. Psychiatric assessment included the Clinical Global Impression Scale-Severity (CGI-S), the Positive and Negative Sindrome Scale (PANSS), the Calgary Depression Scale for Schizophrenia (CDSS) and the Global Assessment of Functioning (GAF). Insight of illness was evaluated using SUMD. Neuropsychological assessment included Winsconsin Card Sorting Test (WCST), California Verbal Learning Test (CVLT), Stroop Test and Trail Making Test (TMT). Differences between the groups were tested using Chi-square test for categorical variables and one-way analysis of variance (ANOVA) for continuous variables. All variables significantly different between the two groups of subjects were subsequently analysed using a logistic regression with a backward stepwise procedure using diagnosis (schizophrenia/schizoaffective disorder) as dependent variable. RESULTS: After backward selection of variables, four variables predicted a schizoaffective disorder diagnosis: marital status, a higher number of admission, better attentive functions and awareness of specific signs or symptoms of disease. The prediction model accounted for 55% of the variance of schizoaffective disorder diagnosis. DISCUSSION: With replication, our findings would allow higher diagnostic accuracy and have an impact on clinical decision making, in light of an amelioration of vocational functioning.

Quality of life in stable schizophrenia: the relative contributions of disorganization and cognitive dysfunction.

OBJECTIVE: The purpose of this study was to examine the relative contributions of disorganization and cognitive dysfunction to quality of life (QOL) in patients with stable schizophrenia. METHODS: A total of 276 consecutive outpatients with stable schizophrenia were enrolled in a cross-sectional study. We performed a mediation analysis to assess the specific effect of disorganization on QOL, as assessed by the Heinrichs-Carpenter Quality of Life Scale (QLS), and the possible mediating role of cognitive dysfunction. RESULTS: Our findings were as follows: (i) disorganization was negatively related to the total QLS score; (ii) disorganization was negatively related to two of the four QLS domains, namely the role-functioning domain (occupational/educational) and the intrapsychic functioning domain (e.g., motivation, curiosity, and empathy); and (iii) verbal memory was a partial mediator of the relationship between disorganization and QLS (the total score and the two above-mentioned domains). CONCLUSIONS: Disorganization demonstrated direct and indirect effects via verbal memory on two domains of functioning, as measured by the QLS. These results highlight the importance of improving disorganization and cognition (particularly verbal memory) to improve the functional outcomes of patients with schizophrenia.

Correlations of attitudes toward antipsychotic drugs with insight and objective psychopathology in schizophrenia.

OBJECTIVE: The aim of this cross-sectional study was to examine the relationships between attitudes toward antipsychotics, insight, and other clinical variables in stable schizophrenia. METHODS: Fifty Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision-(DSM-IV-TR)-diagnosed schizophrenic outpatients were evaluated through a psychiatric assessment. Drug attitudes were measured using the Drug Attitude Inventory and insight using the Scale for the Assessment of Unawareness of Mental Disorder. Differences between patients taking first- or second-generation antipsychotics were investigated. RESULTS: Lack of insight, more severe scores on the positive and general psychopathology subscales of the Positive and Negative Syndrome Scale (PANSS), and later age at onset of schizophrenia correlated with worse global medication attitude. The multiple regression analysis revealed that unawareness of the need of treatment predicted poorer drug global attitude (R(2) = 0.312). Patients taking second-generation antipsychotics showed lower negative attitudes and better global drug attitudes than patients treated with neuroleptics. CONCLUSION: The impact of the awareness of the need for treatment on global medication attitude needs to be a main focus of interventions targeting compliance.