Magnetically responsive chitosan-pectin films incorporating Fe3O4 nanoparticles with enhanced antimicrobial activity.

Chitosan-pectin films with iron oxide (Fe3O4) magnetic nanoparticles were prepared by solution casting in order to produce biopolymer based magnetically active materials. Infrared (FTIR) spectra indicated physical interactions between the matrix and nanoparticles, corroborated by differential scanning calorimetry (DSC) results. In addition, thermal characterization suggested that the interactions between chitosan, pectin and the nanoparticles resulted in a less compact structure, influencing the film mechanical properties. Regarding vibrating-sample magnetometry (VSM) and electrical analysis, chitosan-pectin films with Fe3O4 nanoparticles showed ferrimagnetic behavior, with an increase of the dielectric constant as the nanoparticle concentration increased. Furthermore, films displayed enhanced antimicrobial activity against Escherichia coli (Gram-negative) and Staphylococcus epidermidis (Gram-positive) bacteria. Therefore, chitosan-pectin films with Fe3O4 magnetic nanoparticles provide promising results for active and intelligent food packaging applications.

Efecto del Programa de Ejercicios de Otago en la fragilidad de personas entre 65 y 80 años / Effect of the Otago Exercise Programme on the frailty of people between 65 and 80 years old

Objetivo: Evaluar el efecto del Programa de Ejercicios de Otago en la fragilidad de personas entre 65 y 80 años no institucionalizadas y estudiar factores asociados a la fragilidad. Método: Estudio pre-post test (basal y tras 12 meses) sin grupo control en personas de entre 65-80 años (que viven en la comunidad y con deambulación independiente) tras formarles en el Programa de Ejercicios de Otago en 5 sesiones: semanas 1, 2, 4 y 8, y una sesión de refuerzo a los 6 meses. Los pacientes se seleccionaron en 3 áreas de salud (n=200). La fragilidad se evaluó con la escala FRAIL. Resultados: Las personas que comenzaron el estudio fueron 198 y terminaron el seguimiento de 12 meses 161. La edad promedio de la muestra fue de 72,28 años; predominio del sexo femenino: 64,65%; nivel de estudios bajo 76,50%; personas viviendo solas 24,50%; sobrepeso en el 42% y obesidad grado i en el 32,32%. Se observan diferencias significativas con p=0,023 en el nivel de fragilidad entre el momento basal y a los 12 meses. El análisis exploratorio permitió identificar diferencias significativas antes y después de la intervención por sexo (ser mujer) (p=0,018) y condición de vivir solo (p=0,0468). Conclusiones: El Programa de Ejercicios de Otago presenta resultados positivos en la fragilidad en personas de 65 a 80 años y puede ayudar a mantener la funcionalidad y evitar su deterioro.(AU)

Aim: To evaluate the effect of the Otago Exercise Programme on the frailty of non-institutionalized people between 65 and 80 years of age and study factors associated with frailty. Method: Pre-post test study (baseline and after 12 months) without control group in people aged 65-80 years (living in the community and with independent ambulation) after being trained in the Otago Exercise Programme in 5 sessions: weeks 1, 2, 4 and 8, and a reinforcement session at 6 months. Patients were recruited from 3 health areas (n=200). Frailty was assessed with the FRAIL scale. Results: There were 198 people who started the study and 161 completed the 12-month follow-up. The average age of the sample was 72.28 years; predominance of female sex: 64.65%; low educational level 76.50%; people living alone 24.50%; overweight in 42%, and grade i obesity in 32.32%. Significant differences were observed with a P=.023 in the level of frailty between baseline and 12 months. The exploratory analysis identified significant differences before and after the intervention by sex (being a woman) (P=.018) and condition of living alone (P=.0468). Conclusions: The Otago Exercise Programme shows positive results in frailty in people 65 to 80 years of age and can help maintain function and prevent deterioration.(AU)

Effect of the Otago Exercise Programme on the frailty of people between 65 and 80 years old.

AIM: To evaluate the effect of the Otago Exercise Programme on the frailty of non-institutionalized people between 65 and 80 years of age and study factors associated with frailty. METHOD: Pre-post test study (baseline and after 12 months) without control group in people aged 65-80 years (living in the community and with independent ambulation) after being trained in the Otago Exercise Programme in 5 sessions: weeks 1, 2, 4 and 8, and a reinforcement session at 6 months. Patients were recruited from 3 health areas (n = 200). Frailty was assessed with the FRAIL scale. RESULTS: There were 198 people who started the study and 161 completed the 12-month follow-up. The average age of the sample was 72.28 years; predominance of female sex 64.65%; low educational level 76.50%; people living alone 24.50%; overweight in 42%, and grade I obesity in 32.32%. Significant differences were observed with a P = .023 in the level of frailty between baseline and 12 months. The exploratory analysis identified significant differences before and after the intervention by sex (being a woman) (P = .018) and condition of living alone (P = .0468). CONCLUSIONS: The Otago Exercise Programme prevents positive results in frailty in people 65 to 80 years of age and can help maintain function and prevent deterioration.

3D Printed Chitosan-Pectin Hydrogels: From Rheological Characterization to Scaffold Development and Assessment.

Chitosan-pectin hydrogels were prepared, and their rheological properties were assessed in order to select the best system to develop scaffolds by 3D printing. Hydrogels showed a weak gel behavior with shear thinning flow properties, caused by the physical interactions formed between both polysaccharides, as observed by FTIR analysis. Since systems with high concentration of pectin showed aggregations, the system composed of 2 wt% chitosan and 2 wt% pectin (CHI2PEC2) was selected for 3D printing. 3D printed scaffolds showed good shape accuracy, and SEM and XRD analyses revealed a homogeneous and amorphous structure. Moreover, scaffolds were stable and kept their shape and size after a cycle of compression sweeps. Their integrity was also maintained after immersion in PBS at 37 °C, showing a high swelling capacity, suitable for exudate absorption in wound healing applications.

Evaluation of bioactive release kinetics from crosslinked chitosan films with Aloe vera.

Thermocompression was employed to prepare citric acid-crosslinked chitosan films with Aloe vera (AV) as bioactive compound. Films were easy to handle and mechanical properties did not change with the addition of AV up to 10 wt%, although both TS and EAB decreased for the films with 15 wt% AV, indicating that high AV contents would hinder intermolecular interactions among the formulation components. Maillard reaction occurred between chitosan and citric acid at the processing temperature used (115 °C), while physical interactions took place with AV, as shown by FTIR analysis. All films were insoluble but displayed hydration and limited swelling due to both physical and chemical interactions promoted by AV and citric acid, respectively. A slow AV release, governed by a Fickian diffusion controlled mechanism, and an increase of surface hydrophilicity, which favors cell adhesion, were observed.

Impaired motor cortical plasticity associated with cannabis use disorder in young adults.

Maladaptive cortical plasticity has been described in individuals with heroin and methamphetamine addiction and may mediate other substance abuse disorders. It is unknown whether cannabis dependence in humans alters the capacity for induction of cortical plasticity. The aim of this study was to non-invasively investigate cortical plasticity with transcranial magnetic stimulation in young adults who meet DSM-5 criteria for cannabis use disorder (CUD). Thirty men (ages 20- 30) who used cannabis daily over the previous 6 months (15 diagnosed of CUD) and 15 demographically matched non-users were enrolled in this study. All participants underwent two sessions of theta burst stimulation (TBS) in which either continuous TBS (cTBS; 600 pulses, 80% active motor threshold) or intermittent TBS (iTBS; 2-s train of cTBS repeated every 10 s for a total of 190 s, 600 pulses) was applied over the primary motor cortex. The effects of these protocols were assessed by analysing the contralateral motor evoked potentials (MEPs). The relationships between cortical plasticity and problematic cannabis use, degree of dependence, and nicotine addiction were also investigated. Significant MEP inhibition after cTBS was observed in both cannabis users without CUD and non-users, while this inhibition was not seen in cannabis users with CUD. Strikingly, less motor cortical plasticity was observed in subjects with severe problematic cannabis use. No significant differences between users and non-users were found in the iTBS-induced cortical plasticity measures. Our study provides the first evidence of maladaptive cortical plasticity associated with cannabis use disorder and problematic cannabis use in humans.

Chitosan Films Incorporated with Exopolysaccharides from Deep Seawater Alteromonas Sp.

Two Alteromonas sp. strains isolated from deep seawater were grown to promote the production of exopolysaccharides (EPS, E611 and E805), which were incorporated into chitosan solutions to develop films. The combination of the major marine polysaccharides (chitosan and the isolated bacterial EPS) resulted in the formation of homogenous, transparent, colorless films, suggesting good compatibility between the two components of the film-forming formulation. With regards to optical properties, the films showed low values of gloss, in the range of 5-10 GU, indicating the formation of non-glossy and rough surfaces. In addition to the film surface, both showed hydrophobic character, with water contact angles higher than 100 º, regardless of EPS addition. Among the two EPS under analysis, chitosan films with E805 showed better mechanical performance, leading to resistant, flexible, easy to handle films.

Simultaneous quantification of major cannabinoids and metabolites in human urine and plasma by HPLC-MS/MS and enzyme-alkaline hydrolysis.

A high performance liquid chromatography coupled to tandem mass spectrometry (HPLC-MS/MS) method for simultaneous quantification of Δ9-tetrahydrocannabinol (THC), its two metabolites 11-hydroxy-Δ9-tetrahydrocannabinol (11-OH-THC) and 11-nor-9-carboxy-Δ9-tetrahydrocannabinol (THC-COOH), and four additional cannabinoids (cannabidiol (CBD), cannabigerol (CBG), tetrahydrocannabivarin (THCV), and cannabinol (CBN)) in 1 mL of human urine and plasma was developed and validated. The hydrolysis process was studied to ensure complete hydrolysis of glucuronide conjugates and the extraction of a total amount of analytes. Initially, urine and plasma blank samples were spiked with THC-COOH-glucuronide and THC-glucuronide, and four different pretreatment methods were compared: hydrolysis-free method, enzymatic hydrolysis with Escherichia Coli ß-glucuronidase, alkaline hydrolysis with 10 M NaOH, and enzyme-alkaline tandem hydrolysis. The last approach assured the maximum efficiencies (close to 100%) for both urine and plasma matrices. Regarding the figures of merit, the limits of detection were below 1 ng/mL for all analytes, the accuracy ranged from 84% to 115%, and both within-day and between-day precision were lower than 12%. Finally, the method was successfully applied to real urine and plasma samples from cannabis users. Copyright © 2016 John Wiley & Sons, Ltd.

Targeting the endocannabinoid system: future therapeutic strategies.

The endocannabinoid system (ECS) is involved in many physiological regulation pathways in the human body, which makes this system the target of many drugs and therapies. In this review, we highlight the latest studies regarding the role of the ECS and the drugs that target it, with a particular focus on the basis for the discovery of new cannabinoid-based drugs. In addition, we propose some key steps, such as the creation of a cannabinoid-receptor interaction matrix (CRIM) and the use of metabolomics, toward the development of improved and more specific drugs for each relevant disease.