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1.
Int J Biol Macromol ; 275(Pt 2): 133809, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38996893

RESUMO

Persistent bacterial infections are the leading risk factor that complicates the healing of chronic wounds. In this work, we formulate mixtures of polyvinyl alcohol (P), chitosan (CH), collagen (C), and honey (H) to produce nanofibrous membranes with healing properties. The honey effect at concentrations of 0 % (PCH and PCHC), 5 % (PCHC-5H), 10 % (PCHC-10H), and 15 % (PCHC-15H) on the physicochemical, antibacterial, and biological properties of the developed nanofibers was investigated. Morphological analysis by SEM demonstrated that PCH and PCHC nanofibers had a uniform and homogeneous distribution on their surfaces. However, the increase in honey content increased the fiber diameter (118.11-420.10) and drastically reduced the porosity of the membranes (15.79-92.62 nm). The addition of honey reduces the water vapor transmission rate (WVTR) and the adsorption properties of the membranes. Mechanical tests revealed that nanofibers were more flexible and elastic when honey was added, specifically the PCHC-15H nanofibers with the lowest modulus of elasticity (15 MPa) and the highest elongation at break (220 %). Also, honey significantly improved the antibacterial efficiency of the nanofibers, mainly PCHC-15H nanofibers, which presented the best bacterial reduction rates against Staphylococcus aureus (59.84 %), Pseudomonas aeruginosa (47.27 %), Escherichia coli (65.07 %), and Listeria monocytogenes (49.58 %). In vitro tests with cell cultures suggest that nanofibers were not cytotoxic and exhibited excellent biocompatibility with human fibroblasts (HFb) and keratinocytes (HaCaT), since all treatments showed higher or similar cell viability as opposed to the cell control. Based on the findings, PVA-chitosan-collagen-honey nanofibrous membranes have promise as an antibacterial dressing substitute.


Assuntos
Antibacterianos , Bandagens , Quitosana , Colágeno , Mel , Membranas Artificiais , Nanofibras , Cicatrização , Quitosana/química , Quitosana/farmacologia , Nanofibras/química , Bandagens/microbiologia , Colágeno/química , Antibacterianos/farmacologia , Antibacterianos/química , Humanos , Cicatrização/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Porosidade , Álcool de Polivinil/química , Fibroblastos/efeitos dos fármacos
2.
Int J Pharm X ; 5: 100175, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36950662

RESUMO

Electrospun chitosan nanofibers (QSNFs) enhance the healing process by mimicking skin structure and function. The aim of this study was to analyze the therapeutic effects of QSNFs application on animal skin wounds to identify a potential direction for translational research in dermatology. The PRISMA methodology and the PICO scheme were used. A random effects model and mean difference analysis were applied for the meta-analysis. A meta-regression model was constructed, risk of bias was determined, and methodological quality assessment was performed. Of the 2370 articles collected, 54 studies were selected based on the inclusion and exclusion criteria. The wound healing area was used for building models on the 3rd, 7th, and 14th days of follow-up; the results were - 10.4% (95% CI, -18.2% to -2.6%, p = 0.001), -21.0% (95% CI, -27.3% to -14.7%, p = 0.001), and - 14.0% (95% CI, -19.1 to -8.8%, p = 0.001), respectively. Antioxidants and synthetic polymers combined with QSNFs further reduced skin wound areas (p < 0.05). The results show a more efficient reduction in wound area percentages in experimental groups than in control groups, so QSNFs could potentially be applied in translational human medicine research.

3.
Vet Anim Sci ; 17: 100261, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35856003

RESUMO

Consultation was requested for a 7-year-old Gypsy Vanner male horse with a 2-year history of foreskin injury. Upon revision, an ulcer, 153 cm2 in size, with yellowish granules was observed; a RESVECH 2.0 evaluation revealed a score of 32/35 points. Medical history confirmed multiple failed deworming, anti-inflammatory, and antibiotic treatments with different topical therapies and recurrence in summer. Laboratory results confirmed elevated total proteins (8.8 g/dL) and globulins (5.5 g/dL), negative bacterial and fungal cultures, as well as negative coproparasitoscopic findings, and finally, identification of stable fly larvae (Stomoxys calcitrans) in the feces. Microscopy showed disorganized collagen, thickened tissue, polymorphonuclear cells, and acanthosis without neoplastic tissue or parasite remains. Debridement was performed and systemic treatment with ivermectin, penicillin, and non-steroidal anti-inflammatory drugs (NSAIDs) continued. In addition, 2% chitosan gel and films were applied to the entire surface of the lesion for 72 hours on 30 occasions; vector control with nets and insecticides was performed. On day 94, there was a 6 cm2 surface with involvement of the dermal and epidermal layers, moist epithelial tissue, and diffuse edges, with a RESVECH 2.0 evaluation of 6/35 points. Microscopy showed an intact basement membrane, presence of hair follicles, sweat glands, aligned collagen, and angiogenesis. It was concluded that chronic skin lesions in horses represent a diagnostic challenge, and topical chitosan is an adequate treatment due to its biocompatibility and efficacy, in addition to the functional and cosmetic results in dermal regeneration.

4.
Prev Vet Med ; 190: 105325, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33744675

RESUMO

Chitosan is a natural polysaccharide with biocompatibility, biodegradability, nontoxicity, antimicrobial, and hemostatic properties. This biopolymer has been used in different pharmaceutical forms; therefore, it has an attractive potential for dermal applications in veterinary medicine. The aim of this review is to assess the healing potential of chitosan, based on its dermatological effects on animals, to enrich the therapeutic options of veterinary clinicians. A systematic review was conducted based on the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) strategy, retrieving 1,032 studies and selecting 39 after the inclusion and exclusion criteria were applied. The studies included reports with confirmed positive effects (n = 46/99, 46.5 %) (P < 0.05), with positive effects (n = 49.5/99, 49.5 %), and with no effect (n = 4/99, 4 %); none of the studies reported adverse effects. There is an association between frequency of application and a decrease in healing time (P = 0.038); applying chitosan "every 48-72 hours" was the most recommended frequency (n = 10/19, 52.9 %). Chitosan, when applied to skin lesions on animals, produces positive effects on healing, potentially becoming a safe biomaterial for skin treatments in veterinary practice. As an initial protocol, we suggest applying chitosan every 48-72 hours for at least 2 weeks (7 applications).


Assuntos
Quitosana , Dermatologia , Animais , Materiais Biocompatíveis , Quitosana/uso terapêutico , Medicina Veterinária
5.
Curr Mol Pharmacol ; 14(6): 925-934, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33430757

RESUMO

BACKGROUND: The pseudo-cereal quinoa has attracted worldwide attention in recent years, due to it being considered a functional food. This stress-tolerant crop has historically been used by Andean cultures as a staple food. Nowadays, the consumption of quinoa in high-income countries is increasing due to it being associated with numerous health benefits, namely related to cardiovascular health. OBJECTIVE: We have carried out an extensive review on quinoa, including its main uses, applications, and components (nutrients, antinutrients, and bioactives) and their relationship with biological activities and cardiovascular health. Key findings and Conclusions: Quinoa possesses numerous activities, including protection against cardiovascular, metabolic, and degenerative diseases, improvement of the immune system, reduction of symptoms associated with post-menopause, and promotion of muscle mass increase. Some of the quinoa's activities are due to its balanced amino acid profile, high fiber content, presence of phosphorus, iron, potassium, magnesium, vitamin E, and B vitamins. A plethora of bioactives can also be found in quinoa, such as phytosterols, saponins, phenolics, bioactive peptides, and phytoecdysteroids. More research is needed to better understand the mechanisms of action involved in the biological/therapeutic action of some quinoa components, namely those related to the potential to reduce cardiovascular disease (CVD) risk markers. The knowledge of factors that affect quinoa variability, such as processing conditions, is also of great importance for being able to obtain more benefits from this crop.


Assuntos
Doenças Cardiovasculares , Chenopodium quinoa , Doenças Cardiovasculares/tratamento farmacológico , Doenças Cardiovasculares/prevenção & controle , Chenopodium quinoa/química , Chenopodium quinoa/metabolismo , Valor Nutritivo , Fenóis
6.
Environ Sci Pollut Res Int ; 27(35): 44195-44204, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32761347

RESUMO

Mining is an important activity for the economic development of many countries. However, this activity produces toxic residues that pollute water and the environment. The heavy metal removal from effluents of acid mine water is crucial to avoid environmental pollution. The microalga Nannochloropsis oculata was cultured in algal medium, with the addition of 1.16, 1.74, 2.32, 3.48, and 4.64 mg Cu2+ L-1 coming from acid mine water to assess its removal capacity and the effect of copper content on the cell density and lipid productivity. The results showed that N. oculata removed up to 94.88 ± 0.43% at copper concentration than 1.74 mg Cu2+ L-1; additionally, a positive effect on the lipid content was found at copper concentration to be higher, 4.64 mg Cu2+ L-1, yielding 77.04 ± 2.60% of lipid content, twice as high as that achieved in the control culture of 33.058 ± 5.398%, thus potentiating the biodiesel production. These findings are favorable because they indicate that microalgae can remove copper added in the culture and present in acid mine water and can yield high lipid content at the same time. The cell density and growth rate decreased with increased concentrations of copper in the culture medium.


Assuntos
Microalgas , Estramenópilas , Biocombustíveis , Cobre , Lipídeos
7.
Plant Foods Hum Nutr ; 75(2): 252-257, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32212005

RESUMO

Sorghum is a cereal with little use in human diet; however, this grain can provide several nutrients and, additionally, has a high content of phenolic compounds concentrated in bran, which could be beneficial to human health due to its high antioxidant capacity. However, these bioactive compounds are bound within the cell wall matrix; it is necessary to release these compounds to take advantage of their antioxidant properties. The extrusion process increases the accessibility of bound phenolic compounds, breaking their bonds from the bran matrix. The aim of this study was to determine the optimal extrusion conditions for maximizing the phenolic compound content and antioxidant capacity of sorghum bran extrudate. The extrusion process factors evaluated were feed moisture (FM) from 25 to 35% and the fourth extrusion zone temperature (T) in the range of 140-180 °C. Analysis of variance and response surface analysis were used in the evaluation. The prediction coefficient, (FM)2, (T)2 and their interaction (FM)(T) significantly affected the free total phenolic compounds. The antioxidant capacity of the free total phenolic compounds was significantly affected by (FM)2 and (T)2. The optimal extrusion conditions were FM = 30% and T = 160 °C, which provided free total phenolic compounds with a value of 7428.95 µg GAE/g (predicted value: 7810.90 µg GAE/g) and antioxidant capacity with a value of 14.12 µmol TE/g (predicted value: 14.85 µmol TE/g). Results confirmed that extrusion process optimization was useful to increase the content of phenolic compounds and improved the antioxidant capacity of sorghum bran.


Assuntos
Sorghum , Antioxidantes , Dieta , Grão Comestível , Humanos , Fenóis
8.
Saudi J Biol Sci ; 25(1): 130-135, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29379369

RESUMO

Infections, ulcerations, gangrene and, in severe cases, extremity amputation, are common complications among diabetic subjects. Various biomaterials have been utilized for the treatment of these lesions. Chitosan is an amino sugar with a low risk of toxicity and immune response. In this study, we evaluated chitosan topical gel and film treatments for subjects with diabetic ulcerations and wounds associated with diabetes mellitus. In a pre-experimental design, we described the result of chitosan gel and film treatment for wounds and skin ulcers among patients with long-standing diabetes mellitus. We studied 8 diabetic patients with wounds and skin ulcers (long duration and Wagner degree 1-2). Initially, most lesions had some degree of infection, tissue damage and ulceration. At the end of the treatment (topical chitosan) period, the infections were cured. All patients experienced a significant improvement in the initial injury and developed granulation tissue and a healthy skin cover. This report represents one of the few published clinical experience regarding the chitosan for the treatment of skin lesions among diabetic subjects. These results are relevant and promising for the treatment of this disease.

9.
J Ethnopharmacol ; 190: 106-15, 2016 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-27262564

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Tuberculosis (TB) is an infectious disease mainly caused by Mycobacterium tuberculosis (Mtb), which generates 9 million new cases worldwide each year. The Mayo ethnicity of southern Sonora, Mexico is more than 2000 years old, and the Mayos possess extensive knowledge of traditional medicine. AIMS OF THE STUDY: To evaluate the antimycobacterial activity levels of extracts of medicinal plants used by the Mayos against Mtb and Mycobacterium smegmatis (Msm) in the treatment of TB, respiratory diseases and related symptoms. MATERIALS AND METHODS: A total of 34 plant species were collected, and 191 extracts were created with n-hexane, dichloromethane, ethyl acetate (EtOAc), methanol and water. Their minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) were determined against Mtb H37Rv using the microplate alamar blue assay (MABA) and against Msm using the resazurin microplate assay (REMA) at 6 and 2 days of exposure, respectively, and at concentrations of 250-1.9µg/mL (n-hexane extracts) and 1000-7.81µg/mL (extracts obtained with dichloromethane, EtOAc, methanol and water). RESULTS: Rhynchosia precatoria (Willd.) DC. (n-hexane root extract), Euphorbia albomarginata Torr. and A. Gray. (EtOAc shoot extract) and Helianthus annuus L. (n-hexane stem extract) were the most active plants against Mtb H37Rv, with MICs of 15.6, 250, 250µg/mL and MBCs of 31.25, 250, 250µg/mL, respectively. R. precatoria (root) was the only active plant against Msm, with MIC and MBC values of ≥250µg/mL. None of the aqueous extracts were active. CONCLUSIONS: This study validates the medicinal use of certain plants used by the Mayo people in the treatment of TB and related symptoms. R. precatoria, E. albomarginata and H. annuus are promising plant sources of active compounds that act against Mtb H37Rv. To our knowledge, this is the first time that their antimycobacterial activity has been reported. Crude extracts obtained with n-hexane, EtOAc and dichloromethane were the most active against Mtb H37Rv.


Assuntos
Antituberculosos/farmacologia , Euphorbia/química , Fabaceae/química , Helianthus/química , Medicina Tradicional , Mycobacterium smegmatis/efeitos dos fármacos , Mycobacterium tuberculosis/efeitos dos fármacos , Extratos Vegetais/farmacologia , Tuberculose/tratamento farmacológico , Acetatos/química , Antituberculosos/isolamento & purificação , Etnobotânica , Etnofarmacologia , Hexanos/química , Humanos , Cloreto de Metileno/química , México , Testes de Sensibilidade Microbiana , Mycobacterium smegmatis/crescimento & desenvolvimento , Mycobacterium tuberculosis/crescimento & desenvolvimento , Fitoterapia , Extratos Vegetais/isolamento & purificação , Plantas Medicinais , Solventes/química , Tuberculose/microbiologia
10.
Food Chem ; 201: 94-100, 2016 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-26868553

RESUMO

Sulforaphane is a phytochemical that has received attention in recent years due to its chemopreventive properties. However, the uses and applications of this compound are very limited, because is an unstable molecule that is degraded mainly by changes in temperature and pH. In this research, the use of food grade polymers for microencapsulation of sulforaphane was studied by a complex coacervation method using the interaction of oppositely charged polymers as gelatin/gum arabic and gelatin/pectin. The polymers used were previously characterized in moisture content, ash and nitrogen. The encapsulation yield was over 80%. The gelatin/pectin complex had highest encapsulation efficiency with 17.91%. The presence of sulforaphane in the complexes was confirmed by FTIR and UV/visible spectroscopy. The materials used in this work could be a new and attractive option for the protection of sulforaphane.


Assuntos
Brassica/química , Composição de Medicamentos/métodos , Gelatina/química , Goma Arábica/química , Isotiocianatos/química , Pectinas/química , Sementes/química , Sulfóxidos
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