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1.
Front Nutr ; 10: 1134162, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37545576

RESUMEN

Introduction: L-carnitine (LC) has been associated with inflammatory mediator reduction and with downregulating the angiotensin-converting enzyme-2 (ACE2) receptor, which is the target of SARS-CoV-2 attachment. Methods: This pilot phase 2 randomized, double-blind placebo-controlled trial contained two cohorts. Cohort 1 comprised 101 individuals with negative RT-PCR SARS-CoV-2 test results who cohabitated with an individual diagnosed with SARS-CoV-2 infection. Cohort 2 comprised 122 individuals with positive SARS-CoV-2 RT-PCR test results who were asymptomatic or had mild COVID-19 pneumonia symptoms. Participants in each cohort were randomized 1:1 to receive either 2 g elemental oral LC supplementation or placebo daily for 21 days. Primary endpoints included adverse events, SARS-CoV-2 infection incidence in Cohort 1, and disease progressions in Cohort 2. Secondary endpoints included between-group laboratory profile comparisons and Cohort 2 ACE1/ACE2 plasma levels. Disease progression was compared between the Cohort 2 groups using chest computed tomography. Results: In Cohort 1, two SARS-CoV-2 infections occurred in each group. The common adverse events included headache, dyspnea, and tiredness. In Cohort 2, platelet counts were elevated, and fibrinogen levels reduced in the LC group compared with those of the placebo group. Conclusion: Our study showed that LC was well-tolerated and suggests it modulates coagulation pathways. Furthermore, chest computed tomography images of the Cohort 2 LC group showed significant lung lesion improvement, suggesting that LC may slow COVID-19 progression.

2.
Int J Mol Sci ; 24(12)2023 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-37373096

RESUMEN

Osteoarthritis (OA) is a whole-joint disease primarily characterized by the deterioration of hyaline cartilage. Current treatments include microfracture and chondrocyte implantation as early surgical strategies that can be combined with scaffolds to repair osteochondral lesions; however, intra-articular (IA) injections or implantations of mesenchymal stem cells (MSCs) are new approaches that have presented encouraging therapeutic results in animal models and humans. We critically reviewed clinical trials with MSC therapies for OA, focusing on their effectiveness, quality, and outcomes in the regeneration of articular cartilage. Several sources of autologous or allogeneic MSCs were used in the clinical trials. Minor adverse events were generally reported, indicating that IA applications of MSCs are potentially safe. The evaluation of articular cartilage regeneration in human clinical trials is challenging, particularly in the inflammatory environment of osteoarthritic joints. Our findings indicate that IA injections of MSCs are efficacious in the treatment of OA and the regeneration of cartilage, but that they may be insufficient for the full repair of articular cartilage defects. The possible interference of clinical and quality variables in the outcomes suggests that robust clinical trials are still necessary for generating reliable evidence with which to support these treatments. We suggest that the administration of just-sufficient doses of viable cells in appropriate regimens is critical to achieve effective and durable effects. In terms of future perspectives, genetic modification, complex products with extracellular vesicles derived from MSCs, cell encapsulation in hydrogels, and 3D bioprinted tissue engineering are promising approaches with which to improve MSC therapies for OA.


Asunto(s)
Cartílago Articular , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas , Osteoartritis , Animales , Humanos , Cartílago Articular/patología , Osteoartritis/terapia , Osteoartritis/patología , Condrocitos/patología , Células Madre Mesenquimatosas/patología , Ingeniería de Tejidos , Trasplante de Células Madre Mesenquimatosas/métodos
3.
Front Med (Lausanne) ; 10: 1071239, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36817791

RESUMEN

A 23-year-old man started with chest pain 8 h after his first Pfizer-BioNTech COVID-19 vaccination. ECG evaluation showed sinus tachycardia with ST-segment elevation in D1, AVL, V5, and V6, the findings compatible with acute subepicardial myocardial damage. However, cardiac MRI documented myocardial fibrosis, with cardiac late enhancement non-ischemic pattern with diffuse edema. He had no other symptoms to suggest another etiology than the vaccination. The patient was hospitalized and received corticosteroid (prednisolone) daily. Then, 2 weeks after hospitalization, all laboratory parameters and ECG were normal and the patient was discharged from the hospital. The patient had a history of Wolf-Parkinson White that was corrected with ablation when he was 11 years old. This report calls attention to myocardial adverse reaction risk for mRNA COVID-19 vaccines for people with a previous cardiac disease history.

4.
Polymers (Basel) ; 14(18)2022 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-36145867

RESUMEN

To modify its characteristics, expand its applicability, and, in some cases, its processability, new blends using ultra-high-molecular-weight polyethylene (UHMWPE) have been developed. In this study, three different formulations of linear low-density polyethylene (LLDPE) and UHMWPE blends were prepared with 15, 30, and 45% (% w/w) UHMWPE in the LLDPE matrix. All mixtures were prepared by hot pressing and were immersed in water for one hour afterwards at a controlled temperature of 90 °C to relieve the internal stresses that developed during the forming process. The thermal characterization showed that the blends showed endothermic peaks with different melting temperatures, which may be the result of co-crystallization without mixing between the polymers during the forming process. The mechanical characteristics presented are typical of a ductile material, but with the increase in the percentage of UHMWPE, there was a decrease in the ductility of the blends, as the elongation at rupture of the blends was higher than that of the pure components. The morphologies observed by SEM indicate that there were two phases in the blends. This is the result of the system's immiscibility due to the mode of preparation of the blends, wherein the two polymers may not have mixed intimately, confirming the results found with the thermal analyses.

5.
Pharmaceutics ; 14(6)2022 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-35745794

RESUMEN

The use of innate products for the fast and efficient promotion of healing process has been one of the biomedical sector's main bets for lesion treatment modernization process. The aim of this study was to develop and characterize bacterial cellulose-based (BC) wound dressings incorporated with green and red propolis extract (2 to 4%) and the active compounds p-coumaric acid and biochanin A (8 to 16 mg). The characterization of the nine developed samples (one control and eight active wound dressings) evidenced that the mechanics, physics, morphological, and barrier properties depended not only on the type of active principle incorporated onto the cellulosic matrix, but also on its concentration. Of note were the results found for transparency (28.59-110.62T600 mm-1), thickness (0.023-0.046 mm), swelling index (48.93-405.55%), water vapor permeability rate (7.86-38.11 g m2 day-1), elongation (99.13-262.39%), and antioxidant capacity (21.23-86.76 µg mL-1). The wound dressing based on BC and red propolis was the only one that presented antimicrobial activity. The permeation and retention test revealed that the wound dressing containing propolis extract presented the most corneal stratum when compared with viable skin. Overall, the developed wound dressing showed potential to be used for treatment against different types of dermal lesions, according to its determined proprieties.

6.
Front Microbiol ; 13: 1093464, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36741879

RESUMEN

Background: Global demand for food products derived from alternative proteins and produced through sustainable technological routes is increasing. Evaluation of research progress, main trends and developments in the field are valuable to identify evolutionary nuances. Methods: In this study, a bibliometric analysis and search of patents on alternative proteins from fermentation processes was carried out using the Web of Science and Derwent World Patents Index™ databases, using the keywords and Boolean operators "fermentation" AND "single cell protein" OR "single-cell protein." The dataset was processed and graphics generated using the bibliometric software VOSviewer and OriginPro 8.1. Results: The analysis performed recovered a total of 360 articles, of which 271 were research articles, 49 literature review articles and 40 publications distributed in different categories, such as reprint, proceedings paper, meeting abstract among others. In addition, 397 patents related to the field were identified, with China being the country with the largest number of publications and patents deposits. While this topic is largely interdisciplinary, the majority of work is in the area of Biotechnology Applied Microbiology, which boasts the largest number of publications. The area with the most patent filings is the food sector, with particular emphasis on the fields of biochemistry, beverages, microbiology, enzymology and genetic engineering. Among these patents, 110 are active, with industries or companies being the largest depositors. Keyword analysis revealed that the area of study involving single cell protein has included investigation into types of microorganisms, fermentation, and substrates (showing a strong trend in the use of agro-industrial by-products) as well as optimization of production processes. Conclusion: This bibliometric analysis provided important information, challenges, and trends on this relevant subject.

7.
Polymers (Basel) ; 13(7)2021 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-33810443

RESUMEN

The growing demand in the consumer market for products with sustainable technologies has motivated new applications using overmolded natural fiber composites. Therefore, studies have been conducted mainly to understand the adhesive properties of overmolded parts. In the present study, a polypropylene (PP) composite with 30% coconut fibers without additives was developed with the aid of a corotating twin screw extruder. Subsequently, a multicomponent injection mold was developed based on the geometry of the ISO 527 type I specimen, in which samples overmolded with PP and PP-coconut-fiber composite, with the overlap in the central area, were obtained to evaluate the adhesive strength of dissimilar materials. The objective of this study was to evaluate the bond between PP and PP-coconut-fiber composite under different processing conditions using an adhesive strength testing device to perform a pure shear analysis. The experimental conditions followed a statistical design considering four factors in two levels and a significance level of 5%. The results indicated that adhesive strength increased significantly as the overlap area increased. It was observed that temperature and injection flow rate were the factors that most contributed to strengthening the bonds of dissimilar materials.

8.
Materials (Basel) ; 14(2)2021 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-33477891

RESUMEN

One of the major benefits of biomedicine is the use of biocomposites as wound dressings to help improve the treatment of injuries. Therefore, the main objective of this study was to develop and characterize biocomposites based on bacterial cellulose (BC) with different concentrations of collagen and starch and characterize their thermal, morphological, mechanical, physical, and barrier properties. In total, nine samples were produced with fixed amounts of glycerol and BC and variations in the amount of collagen and starch. The water activity (0.400-0.480), water solubility (12.94-69.7%), moisture (10.75-20.60%), thickness (0.04-0.11 mm), water vapor permeability (5.59-14.06 × 10-8 g·mm/m2·h·Pa), grammage (8.91-39.58 g·cm-2), opacity (8.37-36.67 Abs 600 nm·mm-1), elongation (4.81-169.54%), and tensile strength (0.99-16.32 MPa) were evaluated and defined. In addition, scanning electron microscopy showed that adding biopolymers in the cellulose matrix made the surface compact, which also influenced the visual appearance. Thus, the performance of the biocomposites was directly influenced by their composition. The performance of the different samples obtained resulted in them having different potentials for application considering the injury type. This provides a solution for the ineffectiveness of traditional dressings, which is one of the great problems of the biomedical sector.

9.
Polymers (Basel) ; 12(2)2020 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-31991906

RESUMEN

Bacterial cellulose (BC) has received considerable attention due to its unique properties, including an ultrafine network structure with high purity, mechanical strength, inherent biodegradability, biocompatibility, high water-holding capacity and high crystallinity. These properties allow BC to be used in biomedical and industrial applications, such as medical product. This research investigated the production of BC by Gluconacetobacter hansenii ATCC 23769 using different carbon sources (glucose, mannitol, sucrose and xylose) at two different concentrations (25 and 50 g∙L-1). The BC produced was used to develop a biocomposite with montmorillonite (MMT), a clay mineral that possesses interesting characteristics for enhancing BC physical-chemical properties, at 0.5, 1, 2 and 3% concentrations. The resulting biocomposites were characterized in terms of their physical and barrier properties, morphologies, water-uptake capacities, and thermal stabilities. Our results show that bacteria presented higher BC yields in media with higher glucose concentrations (50 g∙L-1) after a 14-day incubation period. Additionally, the incorporation of MMT significantly improved the mechanical and thermal properties of the BC membranes. The degradation temperature of the composites was extended, and a decrease in the water holding capacity (WHC) and an improvement in the water release rate (WRR) were noted. Determining a cost-effective medium for the production of BC and the characterization of the produced composites are extremely important for the biomedical applications of BC, such as in wound dressing materials.

10.
Ciênc. rural (Online) ; 49(2): e20180587, 2019. tab
Artículo en Inglés | LILACS | ID: biblio-1045299

RESUMEN

ABSTRACT: Brazil has the largest herd of goats of the American continent, with more than 9 million head. Goat farming is considered a growing and important activity for the economy, mainly in the northeastern region of Brazil .In this research, were determined the lipid content and the composition of fillet and shank fatty acids of young goats, registered in the inspection sector of the Ministry of Agriculture and marketed in the city of Salvador (Bahia). The average percentage of total lipids in the fillet was 1.68±0.04 and in the shank of 4.02±0.09, this is a significant difference between the cuts (P<0.05). Twenty-seven (27) fatty acids were identified in the cuts, most are palmitic acid (C16:0), stearic acid (C18:0) and oleic acid (C18:1ω9) present in 21.32%, 20.39%, 34.49% in the fillet and 21.74%, 21.94%, 33.38% in the shank, respectively. The total sums of saturated and polyunsaturated fatty acids ranged of 42.75 to 45.23% and 14.04 to 12.35% between fillet and shank cuts, respectively. The ratio of PUFA/SFA was 0.35 for fillet and 0.15 for shank, and the ratio ω6/ω3 was 3.07 for fillet and 2.27 for shank. Therefore, is a significant difference in total lipid content and fatty acid composition in commercial cuts of beef fillet and shank.


RESUMO: O Brasil apresenta a maior população de caprinos do continente americano, com mais de nove milhões de cabeças, a caprinocultura é considerada uma atividade em ascensão e de grande importância para a economia, principalmente da região nordeste. No presente trabalho foram determinados o teor de lipídios totais e o perfil de ácidos graxos de amostras de filé e pernil de caprinos juvenil, registrados em órgãos de inspeção do Ministério da Agricultura e comercializados na cidade de Salvador (Bahia). O percentual médio de lipídios totais no filé foi de 1,68±0,04 e no pernil de 4,02±0,09, com diferenças significativas entre os cortes (p<0,05). Foram identificados nos cortes, vinte e sete ácidos graxos, sendo os majoritários os ácidospalmítico (C16:0), esteárico (C18:0) e oleico (C18:1ω9) presentes em 21,32%, 20,39%, 34,49% no filé, e 21,74%, 21,94%, 33,38% no pernil, respectivamente. Os somatórios totais de ácidos graxos saturados e poli-insaturados variaram de 42,75 a 45,23% e de 14,04 a 12,35%, entre os cortes de filé e de pernil, respectivamente. A razão entre AGPI/AGS foi de 0,35 para o filé e de 0,15 para o pernil, e a razão ω6/ω3 foi de 3,07 para o filé e de 2,27 para o pernil. Constatou-se que existe uma diferença significativa no teor de lipídios totais e da composição de ácidos graxos em cortes comerciais de filé e pernil de carne caprina.

11.
PLoS One ; 12(3): e0172585, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28358806

RESUMEN

Propolis is known for its biological properties and its preparations have been continuously investigated in an attempt to solve the problem of their standardization, an issue that limits the use of propolis in food and pharmaceutical industries. The aim of this study was to evaluate in vitro antioxidant, antimicrobial, antiparasitic, and cytotoxic effects of extracts of red, green, and brown propolis from different regions of Brazil, obtained by ethanolic and supercritical extraction methods. We found that propolis extracts obtained by both these methods showed concentration-dependent antioxidant activity. The extracts obtained by ethanolic extraction showed higher antioxidant activity than that shown by the extracts obtained by supercritical extraction. Ethanolic extracts of red propolis exhibited up to 98% of the maximum antioxidant activity at the highest extract concentration. Red propolis extracts obtained by ethanolic and supercritical methods showed the highest levels of antimicrobial activity against several bacteria. Most extracts demonstrated antimicrobial activity against Staphylococcus aureus. None of the extracts analyzed showed activity against Escherichia coli or Candida albicans. An inhibitory effect of all tested ethanolic extracts on the growth of Trypanosoma cruzi Y strain epimastigotes was observed in the first 24 h. However, after 96 h, a persistent inhibitory effect was detected only for red propolis samples. Only ethanolic extracts of red propolis samples R01Et.B2 and R02Et.B2 showed a cytotoxic effect against all four cancer cell lines tested (HL-60, HCT-116, OVCAR-8, and SF-295), indicating that red propolis extracts have great cytotoxic potential. The biological effects of ethanolic extracts of red propolis revealed in the present study suggest that red propolis can be a potential alternative therapeutic treatment against Chagas disease and some types of cancer, although high activity of red propolis in vitro needs to be confirmed by future in vivo investigations.


Asunto(s)
Antiinfecciosos/farmacología , Antioxidantes/farmacología , Proliferación Celular/efectos de los fármacos , Própolis/farmacología , Antiparasitarios/farmacología , Brasil , Candida albicans/efectos de los fármacos , Candida albicans/patogenicidad , Cromatografía Líquida de Alta Presión , Escherichia coli/efectos de los fármacos , Escherichia coli/patogenicidad , Humanos , Pruebas de Sensibilidad Microbiana , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/patogenicidad
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