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1.
Front Immunol ; 15: 1391949, 2024.
Article in English | MEDLINE | ID: mdl-38765015

ABSTRACT

Dimethyl fumarate (DMF, Tecfidera) is an oral drug utilized to treat relapsing-remitting multiple sclerosis (MS). DMF treatment reduces disease activity in MS. Gastrointestinal discomfort is a common adverse effect of the treatment with DMF. This study aimed to investigate the effect of DMF administration in the gut draining lymph nodes cells of C57BL6/J female mice with experimental autoimmune encephalomyelitis (EAE), an animal model of MS. We have demonstrated that the treatment with DMF (7.5 mg/kg) significantly reduces the severity of EAE. This reduction of the severity is accompanied by the increase of both proinflammatory and anti-inflammatory mechanisms at the beginning of the treatment. As the treatment progressed, we observed an increasing number of regulatory Foxp3 negative CD4 T cells (Tr1), and anti-inflammatory cytokines such as IL-27, as well as the reduction of PGE2 level in the mesenteric lymph nodes of mice with EAE. We provide evidence that DMF induces a gradual anti-inflammatory response in the gut draining lymph nodes, which might contribute to the reduction of both intestinal discomfort and the inflammatory response of EAE. These findings indicate that the gut is the first microenvironment of action of DMF, which may contribute to its effects of reducing disease severity in MS patients.


Subject(s)
Dimethyl Fumarate , Encephalomyelitis, Autoimmune, Experimental , Lymph Nodes , Mice, Inbred C57BL , T-Lymphocytes, Regulatory , Animals , Dimethyl Fumarate/pharmacology , Dimethyl Fumarate/therapeutic use , Encephalomyelitis, Autoimmune, Experimental/drug therapy , Encephalomyelitis, Autoimmune, Experimental/immunology , Lymph Nodes/immunology , Lymph Nodes/drug effects , Mice , Female , T-Lymphocytes, Regulatory/immunology , T-Lymphocytes, Regulatory/drug effects , Mesentery , Cytokines/metabolism , Immunosuppressive Agents/pharmacology , Immunosuppressive Agents/therapeutic use , Disease Models, Animal
2.
Foods ; 12(21)2023 Oct 31.
Article in English | MEDLINE | ID: mdl-37959101

ABSTRACT

Natural polymer-based adhesives are green alternatives, necessary to reduce the problems impacted by synthetic adhesives. Starch and gelatin have extraordinary potential for the synthesis of biobased adhesives. Citric acid (CA), a natural acid, induces the crosslinking and hydrolyzing of both gelatin and starch. In this sense, this work deals with the use of gelatin capsule residues as a promising material to produce biobased adhesives in combination with cassava starch in the presence of different CA concentrations characterizing their mechanical, physicochemical and microstructural properties. Depending on CA concentration, formulations adjusted to different applications can be obtained such as liquid and pressure-sensitive adhesive films. The inclusion of CA allows us not only to improve the applicability of the system since it modifies the flowability of the adhesives as evidenced by the observed changes in the viscosity (from 158.3 to 90.3 for formulations with 20 and 80% CA, respectively). In addition, mechanical profiles showed that the inclusion of CA increased the adhesive bond strength (from 2230.7 to 2638.7 for formulations with 20 and 80% CA, respectively). Structural modifications induced by CA in adhesive formulations were highlighted by ATR-FTIR analysis.

3.
Int J Biol Macromol ; 248: 125980, 2023 Sep 01.
Article in English | MEDLINE | ID: mdl-37506795

ABSTRACT

A nanostructured device based on poly(vinyl alcohol) (PVA) loaded with a cross-linked chitosan (CH) emulsion, soy lecithin, and peppermint essential oil (Mentha piperita) was designed for topical applications using an electrospinning instrument coupled to a rotary drum collector. Different suspensions were obtained by varying the PVA to emulsion ratio (PVA:Em) 87.5:12.5, 82:18, and 75:25, using a PVA solution as a control. ATR-FTIR spectra confirmed the interactions among the components of the system. Scanning electron microscopy (SEM) of the mats evinced that the aligned fiber diameter decreased with higher proportions of emulsion while dynamic mechanical analysis (DMA) revealed a decrease in the storage modulus. The entrapment of the functionalized emulsions not only improved the elongation of the matrices but also provided them with greater structural integrity compared to the single PVA matrix. The most favorable formulation in terms of mechanical properties was found to be the 82:18 ratio. After 1 h of close contact between the 82:18 matrix and a porcine skin explant, the latter was examined by confocal microscopy, which revealed the localization of the essential oil mainly on the surface of the stratum corneum (SC).However, after 7 h of contact, the distribution of the peppermint EO throughout the viable epidermis was observed, which was further supported by ATR-FTIR studies. Tailored electrospun matrices would have potential applications as devices for topical or transdermal treatments due to their vehiculization role that allows the diffusion of peppermint essential oil as a skin penetration enhancer.


Subject(s)
Chitosan , Nanofibers , Oils, Volatile , Mentha piperita/chemistry , Nanofibers/chemistry , Emulsions , Chitosan/chemistry , Oils, Volatile/chemistry , Polyvinyl Alcohol/chemistry
4.
Int J Biol Macromol ; 247: 125423, 2023 Aug 30.
Article in English | MEDLINE | ID: mdl-37343607

ABSTRACT

Adhesives formulated with native starches have high viscosity, low solids content, poor bond strength and stability due to the starch retrogradation. To overcome this problem, a strategy is the starch treatment with NaOH solution combined with urea, capable of intercalating in the polymeric chains of starch. The aims of this work were to develop adhesives based on chemically modified cassava starch with different NaOH:urea ratios and to study in depth the effect induced by the addition of different concentrations of alkali and urea in the adhesive capacity of formulations that determine their subsequent application in paper-based packaging. Firmness and consistency of the adhesive increased for the 1:1 ratio while it decreased for the NaOH:urea 2:1 ratio, suggesting that the hydrolysis of polymer chains occurred. Additionally, adhesives prepared with 15 % starch maintaining NaOH:urea ratios of 0.5:1: and 1:1 exhibited the highest stress values. ATR-FTIR studies supported the results obtained. It was possible to obtain formulations with different adhesive properties with applications in paper-based packaging. From the analysis of the studied parameters, the combination of 15 % w/w cassava starch with a ratio of NaOH:urea 1:1 allows obtaining adhesives with adequate consistency and adhesive capacity which remain stable during the adhesive storage.


Subject(s)
Adhesives , Starch , Starch/chemistry , Sodium Hydroxide , Adhesives/chemistry , Urea/chemistry , Viscosity
5.
Foods ; 12(5)2023 Mar 02.
Article in English | MEDLINE | ID: mdl-36900574

ABSTRACT

Food loss and waste occur for many reasons, from crop processing to household leftovers. Even though some waste generation is unavoidable, a considerable amount is due to supply chain inefficiencies and damage during transport and handling. Packaging design and materials innovations represent real opportunities to reduce food waste within the supply chain. Besides, changes in people's lifestyles have increased the demand for high-quality, fresh, minimally processed, and ready-to-eat food products with extended shelf-life, that need to meet strict and constantly renewed food safety regulations. In this regard, accurate monitoring of food quality and spoilage is necessary to diminish both health hazards and food waste. Thus, this work provides an overview of the most recent advances in the investigation and development of food packaging materials and design with the aim to improve food chain sustainability. Enhanced barrier and surface properties as well as active materials for food conservation are reviewed. Likewise, the function, importance, current availability, and future trends of intelligent and smart packaging systems are presented, especially considering biobased sensor development by 3D printing technology. In addition, driving factors affecting fully biobased packaging design and materials development and production are discussed, considering byproducts and waste minimization and revalorization, recyclability, biodegradability, and other possible ends-of-life and their impact on product/package system sustainability.

6.
Int J Biol Macromol ; 148: 898-907, 2020 Apr 01.
Article in English | MEDLINE | ID: mdl-31981660

ABSTRACT

This work was focused on evaluating the effects of polycarboxylic acid addition and retrogradation phenomenon on tribological performance, thermal, and mechanical properties of both, bioadhesives and sustainable panels. The rheological behavior of adhesives was affected by retrogradation, exhibiting formulations containing CA higher elastic modulus than those with BTCA, regardless of the acid concentration. With regard to tribomechanical properties, panels formulated with CA20 and BTCA80 adhesives presented the lower friction coefficient and wear degree. Thermocompression process induced a crosslinking reaction between wood fibers and starch-based adhesives, leading to more hydrophobic and thermally stable matrices in the presence of BTCA. The selection of the adhesive formulation depends on the moment of its use, since retrogradation limits its performance and that of the derived sustainable panels, being the adhesive CA20 more appropriate in freshly prepared formulations. Meanwhile, when the storage of the adhesive prepared in batch is required, the BTCA80 formulation would be more suitable. Thus, bioinspired materials can provide a valuable insight towards incorporating starch-based adhesives for wood applications.


Subject(s)
Adhesives/chemistry , Biocompatible Materials/chemistry , Starch/chemistry , Chemical Phenomena , Materials Testing , Mechanical Phenomena , Spectrum Analysis , Thermogravimetry
7.
Int J Biol Macromol ; 123: 189-200, 2019 Feb 15.
Article in English | MEDLINE | ID: mdl-30414906

ABSTRACT

Chitosan-based nanocomposites have a significant industrial impact related to the possibility to design and create new materials and structures. Cellulose nanocrystals (CNC) can be extracted from microcrystalline cellulose (MCC) by controlled acid hydrolysis with H2SO4. This work was focused on: to study the microstructure of CNC isolated from MCC after different hydrolysis times; to develop nanocomposites chitosan-based films; to characterize their structural and thermo-mechanical properties; to analyze the spectral differences among samples by means of ATR-FTIR in combination with principal component analysis (PCA) and square partial minimums model (PLS). It is worth noting that the selected condition for isolate the CNC from MCC was the acid treatment for 2 h, evidenced by size measurements. This fact was supported by transmission electron microscope (TEM) and dynamic light scattering (DLS). In this regard, SEM studies of films showed an assembly process between the nanocelluloses and the CH matrix. The incorporation of CNC into the films resulted in strong interactions between the filler and the matrix demonstrating the affinity between the phases and modifying the mechanical profiles. In summary, CNC was found to be a satisfactory reinforcing agent in biodegradable nanocomposite chitosan-based packaging and are promising as a means to develop tailor-made materials.


Subject(s)
Cellulose/chemistry , Chitosan/chemistry , Nanoparticles/chemistry , Cellulose/ultrastructure , Hydrolysis , Microscopy, Electron, Transmission , Nanocomposites/ultrastructure , Nanoparticles/ultrastructure , Spectroscopy, Fourier Transform Infrared , Sulfur Acids/chemistry , Tensile Strength
8.
J Agric Food Chem ; 66(38): 10033-10040, 2018 Sep 26.
Article in English | MEDLINE | ID: mdl-30036472

ABSTRACT

Individual films of polyhydroxyalkanoates (PHA) and polylactic acid (PLA) and their blends were developed by solvent casting. PHA was obtained from activated sludges from a wastewater-treatment system at a laboratory scale. This work focused on analyzing the microstructural properties and thermal behaviors of individual films of PHA and PLA as well as those of their blends. The behaviors of the biodegradation processes of the individual films and blends were examined from a microstructural point of view. ATR-FTIR spectra indicated the existence of weak molecular interactions between the polymers. The formulation of blend films improved the crystallinity of PLA; additionally, it induced the polymer-recrystallization phenomenon, because crystallized PHA acted as a PLA-nucleating agent. This phenomenon explains the improvements in the films' water-vapor-barrier properties. The blends exposed to a biodegradation process showed an intermediate behavior between PLA and PHA, leading to a consistent basis for designing systems tailored to a particular purpose.


Subject(s)
Polyesters/chemistry , Polyhydroxyalkanoates/chemistry , Hot Temperature , Spectroscopy, Fourier Transform Infrared , Surface Properties
9.
Ultrason Sonochem ; 42: 795-804, 2018 Apr.
Article in English | MEDLINE | ID: mdl-29429733

ABSTRACT

This work was focused on the correlation between the structural and techno-functional properties of ultrasound treated cassava starch for the preparation of tailor-made starch-based ingredients and derivatives. Furthermore, the effect of treatment time, sample conditioning and ultrasound amplitude was studied. Ultrasonic treatment of cassava starch induced structural disorganization and microstructural changes evidenced mainly in the morphological characteristics of the granules and in their degrees of crystallinity. These structural modifications were supported by ATR-FTIR and SEM and CSLM studies as well as DRX and thermal analysis. The selection of the processing conditions is critical due to the complete gelatinization of the starch was produced with the maximum amplitude tested and without temperature control. Rheological dynamical analysis indicated changes at the molecular level in starch granules due to the ultrasound treated, revealing the paste stability under refrigeration condition. PCA allow to establish the interrelationships between microstructural and techno-functional properties. In summary, different starch derivatives could be obtained by adjusting the ultrasound treatment conditions depending on their potential applications.

10.
J AOAC Int ; 98(6): 1491-5, 2015.
Article in English | MEDLINE | ID: mdl-26651560

ABSTRACT

Lighting in the working environment plays a significant role on the degree of degradation of photosensitive, thermolabile compounds and on working efficiency. Light emitting diodes (LEDs) are semiconductor light emitting devices that are promising artificial light sources with easy modulation of light wave signals and are also known for low heat generation. Therefore, the effect of polychromatic LED light was tested in the working environment using the drug compounds montelukast, nifedipine, and clavulanic acid, which are known to be photosensitive or thermolabile. As a control, other lighting sources like a sodium lamp, a classic (incandescent, tungsten) lamp, and indirect sunlight were also used in this study. All the experiments were carried out with methanolic solutions at room temperature. An Acquity UPLC/MS/MS system was used for quantification of the main analytes and degradation products. Under the tested conditions, LED lighting proved to be more suitable for handling photosensitive and thermolabile compounds.


Subject(s)
Lighting/methods , Semiconductors , Chromatography, High Pressure Liquid , Drug Stability , Light , Tandem Mass Spectrometry , Temperature
11.
Arch Phys Med Rehabil ; 93(3): 428-33.e12, 2012 Mar.
Article in English | MEDLINE | ID: mdl-22277244

ABSTRACT

OBJECTIVE: To describe the clinical characteristics and short-term pattern of evolution of a sample of patients within 1 year after acquiring a brain injury that led to a vegetative state (VS) or a minimally conscious state (MCS). DESIGN: Cohort study. SETTING: Inpatient brain injury rehabilitation program. PARTICIPANTS: Patients with acquired brain injury (N=32; 47% traumatic, 37.5% hemorrhagic, 15.5% anoxic) who were in a VS or an MCS according to Coma Recovery Scale-Revised (CRS-R) scores. INTERVENTION: Integrative multisensory program comprising daily physical rehabilitation procedures and multimodal sensory stimulation. MAIN OUTCOME MEASURE: All patients were assessed with a Spanish version of the CRS-R at admission and then monthly for at least 6 months or until emergence from MCS. RESULTS: At the time of admission, 12 patients were diagnosed as being in a VS and 20 as being in an MCS. Eight patients were able to emerge from their MCS during follow-up. Seven of these 8 patients were diagnosed as being in an MCS at inclusion, and only 1 was diagnosed as being in a VS. Emergence from an MCS was mostly associated with improvement in both the communication and motor function scales (n=4). Lesser chronicity (P=.01) and the presence of more than visual behavioral responses at admission (P=.05) were both significant predictors of emergence from an MCS. CONCLUSIONS: The CRS-R seems appropriate for establishing an immediate prognosis in this population. A quick referral of these patients for specialized assessment and rehabilitation facilities is recommended.


Subject(s)
Behavior/physiology , Brain Injuries/complications , Persistent Vegetative State/etiology , Persistent Vegetative State/rehabilitation , Adolescent , Adult , Age Factors , Brain Injuries/physiopathology , Cohort Studies , Disability Evaluation , Educational Status , Female , Humans , Male , Middle Aged , Persistent Vegetative State/diagnosis , Prognosis , Prospective Studies , Sex Factors , Spain , Time Factors , Translating , Trauma Severity Indices , Young Adult
12.
J Agric Food Chem ; 60(1): 492-9, 2012 Jan 11.
Article in English | MEDLINE | ID: mdl-22148436

ABSTRACT

This work was focused on studying the changes undergone by heat-treated chitosan films with and without tannic acid addition by monitoring both microstructure and physical properties. Once the films were submitted to different heat treatments, they exhibited higher barrier properties as well as lower water uptake, solubility, and moisture content. These results were also confirmed through X-ray patterns, which changed from the hydrated to the anhydrous conformation, sharper FTIR peaks specifically associated with water, and shift of T(g) toward higher temperatures determined by DMA. Moreover, the modifications caused by the curing process at a molecular scale were observed at a structural level by using a TEM technique. FTIR evaluation granted new insights into the interactions between tannic acid and chitosan molecules, before and after the heat curing, especially due to the occurrence of new peaks and changes in the wavenumber region 1550-1750 cm(-1).


Subject(s)
Chitosan/chemistry , Drug Carriers/chemistry , Hot Temperature , Solubility , Spectroscopy, Fourier Transform Infrared , Tissue Engineering/instrumentation , Water/analysis , X-Ray Diffraction
13.
La Paz; s.n; 2001. 25 p. ilus.
Non-conventional in Spanish | LIBOCS, LIBOSP | ID: biblio-1301212

ABSTRACT

El presente módulo sobre salud ambiental esta dirigido principalmente a los defensores de la salud con el fin de que comprendan que es el medio ambiente y la importancia de mantener una relación de equilibrio con el mismo, para precautelar la salud e integridad personal, toca temas como: estado actual de la salud en Bolivia, deterioro del medio ambiente, que es la slaud ambiental, prevención del daño ambiental y consecuencias del mismo, desastres y que hacer en caso de desastres y participacion de la comunidad


Subject(s)
Environment , Environmental Health/trends , Mentoring , Water , Bolivia , Disasters/prevention & control , Health Education , Environmental Health Education , Soil
14.
La Paz; . (Serie: Anales de la reunión anual de etnología).
Monography in Spanish | LIBOCS, LIBOPI | ID: biblio-1296297

ABSTRACT

Indice: Vialidad prehispánica en el área andina y su vigencia actual. La vida urbana de los negos en La Paz en el Siglo XVIII. Historia social de los grupos originarios. Hotel París:Espectáculo y Sociedad en La Paz 1920-1930. Los orígenes del Aymara y el Kichua. La Etnofarmacología:Contribución de la Medicina Popular a la CIencia Moderna. Jamachínaka:Aves en un contexto Aymara. Crianza de la Uywa en la Sociedad Pastoril Aymara. El Jilaqata en el coqueo en los Andes. Derechos de los pueblos y naciones aymaras. Prospección etnológica preliminar en San José de Uchupiamonas, Provincia Iturralde, Departamento de La Paz. Tahuantinsuyo Fausto Raynaga Conversando con Víctor Hugo Cárdenas. Tiwulax Kunans Atipkaspapi (El zorro no puede vencer nunca) Una lectura de los cuentos del zorro. Primera visita a los Eseïejja. Lo nuestro usurpación o legado, un problema urbano. Amable Valle:Futuro sin pueblos. Los Ayllus de Calcha, persistencia y renovación. Participación y decisiones comunitarias:Las autoridades originarias de Pisaqéri, Tinkipaya. La recreación social del Aylly:El caso de los Yuras. Liquichiris y Kárisiris:Su relación con los pueblos pre-aymaras. Memoria y resistencia antilatifundista en la ribera del Lago Titikaka 1882'1950. La mujer en los proyectos de desarrollo rural. Dinámica social de los Quechuas en el Oriente Boliviano (caso:San Julián-Santa Cruz)

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