Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 65
Filtrar
1.
AAPS PharmSciTech ; 23(6): 212, 2022 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-35918472

RESUMEN

Squamous cell carcinoma (SCC) represents 20% of cases of non-melanoma skin cancer, and the most common treatment is the removal of the tumor, which can leave large scars. 5-Fluorouracil (5FU) is a drug used in the treatment of SCC, but it is highly hydrophilic, resulting in poor skin penetration in topical treatment. Some strategies can be used to increase the cutaneous penetration of the drug, such as the combination of liposomes containing penetration enhancers, for instance, surfactants, associated with the use of microneedling. Thus, the present work addresses the development of liposomes with penetration enhancers, such as sorbtitan monolaurate, span 20, for topical application of 5-FU and associated or not with the use of microneedling for skin delivery. Liposomes were developed using the lipid film hydration, resulting in particle size, polydispersity index, zeta potential, and 5-FU encapsulation efficiency of 88.08 nm, 0.169, -12.3 mV, and 50.20%, respectively. The presence of span 20 in liposomes potentiated the in vitro release of 5-FU. MTT assay was employed for cytotoxicity evaluation and the IC50 values were 0.62, 30.52, and 24.65 µM for liposomes with and without span 20 and 5-FU solution, respectively after 72-h treatment. Flow cytometry and confocal microscopy analysis evidenced high cell uptake for the formulations. In skin penetration studies, a higher concentration of 5-FU was observed in the epidermis + dermis, corresponding to 1997.71, 1842.20, and 2585.49 ng/cm2 in the passive penetration and 3214.07, 2342.84, and 5018.05 ng/cm2 after pretreatment with microneedles, for solution, liposome without and with span 20, respectively. Therefore, herein, we developed a nanoformulation for 5-FU delivery, with suitable physicochemical characteristics, potent skin cancer cytotoxicity, and cellular uptake. Span 20-based liposomes increased the skin penetration of 5-FU in association of microneedling. Altogether, the results shown herein evidenced the potential of the liposome containing span 20 for topical delivery of 5-FU.


Asunto(s)
Fluorouracilo , Neoplasias Cutáneas , Hexosas , Humanos , Liposomas/metabolismo , Tamaño de la Partícula , Piel/metabolismo , Absorción Cutánea , Neoplasias Cutáneas/tratamiento farmacológico , Neoplasias Cutáneas/metabolismo
2.
Molecules ; 26(9)2021 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-34063701

RESUMEN

Agricultural production is influenced by the water content in the soil and availability of fertilizers. Thus, superabsorbent hydrogels, based on polyacrylamide, natural cashew tree gum (CG) and potassium hydrogen phosphate (PHP), as fertilizer and water releaser were developed. The structure, morphology, thermal stability and chemical composition of samples of polyacrylamide and cashew tree gum hydrogels with the presence of fertilizer (HCGP) and without fertilizer (HCG) were investigated, using X-ray diffractometry (XRD), Fourier Transformed Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), Thermogravimetric Analysis (TGA/DTG) and Energy Dispersive Spectroscopy (EDS). Swelling/reswelling tests, textural analysis, effect of pH, release of nutrients and kinetics were determined; the ecotoxicity of the hydrogels was investigated by the Artemia salina test. The results showed that PHP incorporation in the hydrogel favored the crosslinking of chains. This increased the thermal stability in HCGP but decreased the hardness and adhesion properties. The HCGP demonstrated good swelling capacity (~15,000 times) and an excellent potential for reuse after fifty-five consecutive cycles. The swelling was favored in an alkaline pH due to the ionization of hydrophilic groups. The sustained release of phosphorus in HCGP was described by the Korsmeyer-Peppas model, and Fickian diffusion is the main fertilizer release mechanism. Finally, the hydrogels do not demonstrate toxicity, and HCGP has potential for application in agriculture.


Asunto(s)
Resinas Acrílicas/química , Anacardium , Hidrogeles/química , Gomas de Plantas/química , Animales , Artemia , Reactivos de Enlaces Cruzados , Preparaciones de Acción Retardada , Difusión , Fertilizantes , Hidrógeno/química , Concentración de Iones de Hidrógeno , Cinética , Microscopía Electrónica de Rastreo , Nutrientes , Fosfatos/química , Fósforo , Polímeros/química , Polisacáridos/química , Potasio/química , Espectroscopía Infrarroja por Transformada de Fourier , Árboles , Agua , Difracción de Rayos X
3.
Molecules ; 26(5)2021 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-33652788

RESUMEN

Molybdates are biocidal materials that can be useful in coating surfaces that are susceptible to contamination and the spread of microorganisms. The aim of this work was to investigate the effects of copper doping of hydrated cobalt molybdate, synthesized by the co-precipitation method, on its antibacterial activity and to elucidate the structural and morphological changes caused by the dopant in the material. The synthesized materials were characterized by PXRD, Fourier Transformed Infrared (FTIR), thermogravimetric analysis/differential scanning calorimetry (TG/DSC), and SEM-Energy Dispersive Spectroscopy (SEM-EDS). The antibacterial response of the materials was verified using the Minimum Inhibitory Concentration (MIC) employing the broth microdilution method. The size of the CoMoO4·1.03H2O microparticles gradually increased as the percentage of copper increased, decreasing the energy that is needed to promote the transition from the hydrated to the beta phase and changing the color of material. CoMoO4·1.03H2O obtained better bactericidal performance against the tested strains of Staphylococcus aureus (gram-positive) than Escherichia coli (gram-negative). However, an interesting point was that the use of copper as a doping agent for hydrated cobalt molybdate caused an increase of MIC value in the presence of E. coli and S. aureus strains. The study demonstrates the need for caution in the use of copper as a doping material in biocidal matrices, such as cobalt molybdate.


Asunto(s)
Antiinfecciosos/química , Cobalto/química , Cobre/química , Molibdeno/química , Antiinfecciosos/farmacología , Infecciones Bacterianas/tratamiento farmacológico , Complejos de Coordinación/química , Escherichia coli/efectos de los fármacos , Humanos , Nanopartículas del Metal/química , Pruebas de Sensibilidad Microbiana , Tamaño de la Partícula , Staphylococcus aureus/efectos de los fármacos
4.
Int J Mol Sci ; 18(11)2017 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-29137157

RESUMEN

Silver nanoparticles have been shown to possess considerable antibacterial activity, but in vivo applications have been limited due to the inherent, but low, toxicity of silver. On the other hand, silver nanoparticles could provide cutaneous protection against infection, due to their ability to liberate silver ions via a slow release mechanism, and their broad-spectrum antimicrobial action. Thus, in this work, we describe the development of a carboxymethyl cellulose-based hydrogel containing silver nanoparticles. The nanoparticles were prepared in the hydrogel in situ, utilizing two variants of cashew gum as a capping agent, and sodium borohydride as the reducing agent. This gum is non-toxic and comes from a renewable natural source. The particles and gel were thoroughly characterized through using rheological measurements, UV-vis spectroscopy, nanoparticles tracking analysis, and transmission electron microscopy analysis (TEM). Antibacterial tests were carried out, confirming antimicrobial action of the silver nanoparticle-loaded gels. Furthermore, rat wound-healing models were used and demonstrated that the gels exhibited improved wound healing when compared to the base hydrogel as a control. Thus, these gels are proposed as excellent candidates for use as wound-healing treatments.


Asunto(s)
Anacardium/química , Antibacterianos/farmacología , Carboximetilcelulosa de Sodio/química , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Nanopartículas del Metal/química , Ácidos Ftálicos/química , Plata/farmacología , Cicatrización de Heridas/efectos de los fármacos , Animales , Masculino , Nanopartículas del Metal/ultraestructura , Pruebas de Sensibilidad Microbiana , Tamaño de la Partícula , Pseudomonas aeruginosa/efectos de los fármacos , Ratas Wistar , Reología , Staphylococcus aureus/efectos de los fármacos
5.
Drug Dev Res ; 76(3): 143-51, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25959135

RESUMEN

Long-term use nonsteroidal anti-inflammatory drug is associated with gastrointestinal (GI) lesion formation. The aim of this study was to investigate the protective activity of cashew gum (CG), a complex heteropolysaccharide extracted from Anacardium occidentale on naproxen (NAP)-induced GI damage. Male Wistar rats were pretreated with vehicle or CG (1, 3, 10, and 30 mg/kg, p.o.) twice daily for 2 days; after 1 h, NAP (80 mg/kg, p.o.) was administered. The rats were euthanized on the 2nd day of treatment, 4 h after NAP administration. Stomach lesions were measured using digital calipers. The medial small intestine was used for the evaluation of macroscopic lesion scores. Samples of the stomach and the intestine were used for histological evaluation, and assays for glutathione (GSH), malonyldialdehyde (MDA), and myeloperoxidase (MPO). Additional rats were used to measure gastric mucus and secretion. Pretreatment with CG reduced the macroscopic and microscopic damage induced by NAP. CG significantly attenuated NAP-induced alterations in MPO, GSH, and MDA levels. Furthermore, CG returned adherent mucus levels to normal values. These results suggest that CG has a protective effect against GI damage via mechanisms that involve the inhibition of inflammation and increasing the amount of adherent mucus in mucosa.


Asunto(s)
Anacardium , Enfermedades Gastrointestinales/inducido químicamente , Enfermedades Gastrointestinales/prevención & control , Naproxeno/efectos adversos , Gomas de Plantas/uso terapéutico , Polisacáridos/uso terapéutico , Animales , Enfermedades Gastrointestinales/patología , Masculino , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/uso terapéutico , Gomas de Plantas/aislamiento & purificación , Polisacáridos/aislamiento & purificación , Ratas , Ratas Wistar
6.
J Nanobiotechnology ; 12: 36, 2014 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-25223611

RESUMEN

BACKGROUND: Type I collagen is an abundant natural polymer with several applications in medicine as matrix to regenerate tissues. Silver nanoparticles is an important nanotechnology material with many utilities in some areas such as medicine, biology and chemistry. The present study focused on the synthesis of silver nanoparticles (AgNPs) stabilized with type I collagen (AgNPcol) to build a nanomaterial with biological utility. Three formulations of AgNPcol were physicochemical characterized, antibacterial activity in vitro and cell viability assays were analyzed. AgNPcol was characterized by means of the following: ultraviolet-visible spectroscopy, dynamic light scattering analysis, Fourier transform infrared spectroscopy, atomic absorption analysis, transmission electron microscopy and of X-ray diffraction analysis. RESULTS: All AgNPcol showed spherical and positive zeta potential. The AgNPcol at a molar ratio of 1:6 showed better characteristics, smaller hydrodynamic diameter (64.34 ± 16.05) and polydispersity index (0.40 ± 0.05), and higher absorbance and silver reduction efficiency (0.645 mM), when compared with the particles prepared in other mixing ratios. Furthermore, these particles showed antimicrobial activity against both Staphylococcus aureus and Escherichia coli and no toxicity to the cells at the examined concentrations. CONCLUSIONS: The resulted particles exhibited favorable characteristics, including the spherical shape, diameter between 64.34 nm and 81.76 nm, positive zeta potential, antibacterial activity, and non-toxicity to the tested cells (OSCC).


Asunto(s)
Antibacterianos/farmacología , Colágeno Tipo I/farmacología , Nanopartículas del Metal/química , Plata/farmacología , Antibacterianos/química , Línea Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Técnicas de Química Sintética , Colágeno Tipo I/administración & dosificación , Colágeno Tipo I/química , Evaluación Preclínica de Medicamentos/métodos , Dispersión Dinámica de Luz , Escherichia coli/efectos de los fármacos , Humanos , Nanopartículas del Metal/administración & dosificación , Pruebas de Sensibilidad Microbiana , Microscopía Electrónica de Transmisión , Plata/administración & dosificación , Plata/química , Espectrofotometría Ultravioleta , Espectroscopía Infrarroja por Transformada de Fourier , Staphylococcus aureus/efectos de los fármacos , Difracción de Rayos X
7.
Int J Biol Macromol ; 280(Pt 4): 135995, 2024 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-39326592

RESUMEN

In this work, chitosan/collagen-based membranes loaded with 2,3-dihydrobenzofuran (2,3-DHB) were developed through a simple solvent-casting procedure for use in the treatment of cutaneous Leishmaniasis. The obtained membranes were characterized by elemental analysis, FTIR, TG, DSC, and XRD. Porosity, swelling, mechanical properties, hydrophilicity, and antioxidant activity were analyzed. In addition, assessment to the biocompatibility, through fibroblasts/keratinocytes and in vitro wound healing essays were performed. The obtained results show that the new 2,3-DHB loaded chitosan/collagen membrane presented high porosity and swelling capacity as well as maximum strength, hydrophilicity, and antioxidant activity higher in relation to the control. The tests of antileishmanial activity and the AFM images demonstrate great efficacy of inhibition growth of the parasite, superior to those from the standard therapeutic agent that is currently used: Amphotericin B. The new membranes are biocompatible and stimulated the proliferation of keratinocytes. SEM images clearly demonstrate that fibroblasts were able to adhere, maintained their characteristic morphology. The healing test evidenced that the membranes have adequate environment for promoting cell proliferation and growth. As the conventional treatments often use drugs with high toxicity, the as-developed new membranes proved to be excellent candidate to treat cutaneous Leishmaniasis and can be clearly indicated for further advanced studies in vivo.

8.
Chem Biol Interact ; 398: 111115, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38908811

RESUMEN

In the present study, the effect of sulfonamide-chalcone 185 (SSC185) was investigated against B16-F10 metastatic melanoma cells aggressive actions, besides migration and adhesion processes, by in silico and in vitro assays. In silico studies were used to characterize the pharmacokinetic profile and possible targets of SSC185, using the pkCSM web server, and docking simulations with AutoDock Tools. Furthermore, the antimetastatic effect of SSC185 was investigated by in vitro experiments using MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide), colony, scratch, and cell adhesion assays, and atomic force microscopy (AFM). The molecular docking results show better affinity of SSC185 with the metalloproteinases-2 (MMP-2) and α5ß1 integrin. SSC185 effectively restricts the formation of colonies, migration, and adhesion of B16-F10 metastatic melanoma cells. Through the AFM images changes in cells morphology was identified, with a decrease in the filopodia and increase in the average cellular roughness. The results obtained demonstrate the potential of this molecule in inhibit the primordial steps for metastasis, which is responsible for a worse prognosis of late stage cancer, being the main cause of morbidity among cancer patients.


Asunto(s)
Adhesión Celular , Movimiento Celular , Chalcona , Simulación del Acoplamiento Molecular , Sulfonamidas , Movimiento Celular/efectos de los fármacos , Adhesión Celular/efectos de los fármacos , Sulfonamidas/farmacología , Sulfonamidas/química , Ratones , Animales , Línea Celular Tumoral , Chalcona/farmacología , Chalcona/química , Chalcona/análogos & derivados , Metaloproteinasa 2 de la Matriz/metabolismo , Melanoma Experimental/patología , Melanoma Experimental/tratamiento farmacológico , Melanoma Experimental/metabolismo , Microscopía de Fuerza Atómica , Antineoplásicos/farmacología , Antineoplásicos/química , Chalconas/farmacología , Chalconas/química , Humanos
9.
Int J Biol Macromol ; 275(Pt 1): 133588, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38960246

RESUMEN

The understanding of cancer immunity and antitumor factors generated by natural polysaccharides is not yet fully comprehended. Polysaccharides, like cashew gum (CG), can exhibit immunomodulatory action and may assist in the antitumor process and side effects relieve. This study aimed to determine the antitumor effect of CG alone or in combination with cyclophosphamide (CTX), and its interactions with immune cells, in a murine melanoma model, using the B16-F10 cell line. Tumor growth inhibition, hematological, histopathological, ELISA, flow cytometry, immunofluorescence, and qRT-PCR analyses were performed to elucidate the antitumor potential, involvement of immune cells, and potential toxic effects. CG showed significant tumor growth inhibition, reaching up to 42.9 % alone and 51.4 % in combination with CTX, with mild toxicity to organs. CG enhanced leukocyte count, even in the presence of CTX. Furthermore, CG influenced the activation of tumor-associated macrophages (TAM), characterized by an increase in Il4, as well as a reduction in Ifng, Il1b, Tgfb, and Il6 gene expression. Nevertheless, these effects did not compromise the antitumor activity of CG. In summary, the combination of CG with CTX is a promising approach for leukopenia, one of the most important side effects of cancer treatment and deserves further investigation.


Asunto(s)
Anacardium , Ciclofosfamida , Melanoma Experimental , Animales , Ciclofosfamida/farmacología , Ratones , Melanoma Experimental/tratamiento farmacológico , Melanoma Experimental/patología , Anacardium/química , Gomas de Plantas/química , Gomas de Plantas/farmacología , Línea Celular Tumoral , Modelos Animales de Enfermedad , Citocinas/metabolismo , Macrófagos Asociados a Tumores/efectos de los fármacos , Macrófagos Asociados a Tumores/inmunología
10.
Carbohydr Polym ; 342: 122356, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-39048219

RESUMEN

In this study, we report the synthesis and characterization of pH-responsive nanoconjugates for targeted drug delivery. Galactomannan extracted from D. regia seeds was oxidized to form aldehyde groups, achieving a percentage of oxidation of 25.6 %. The resulting oxidized galactomannan (GMOX) was then copolymerized with PINIPAm-NH2, yielding a copolymer. The copolymer exhibited signals from both GMOX and PNIPAm-NH2 in its NMR spectrum, confirming successful copolymerization. Critical association concentration (CAC) studies revealed the formation of nanostructures, with lower CAC values observed at higher temperatures. The copolymer and GMOX reacted with doxorubicin (DOX), resulting in nanoconjugates with controlled drug release profiles, especially under acidic conditions similar to tumor microenvironments. Cytotoxicity assays demonstrated significant efficacy of the nanoconjugates against melanoma cells with reduced toxicity towards healthy cells. These findings underscore the potential of the pH-responsive nanoconjugates as promising candidates for targeted cancer therapy, offering improved therapeutic efficacy and reduced systemic side effects.


Asunto(s)
Doxorrubicina , Galactosa , Mananos , Nanoconjugados , Doxorrubicina/farmacología , Doxorrubicina/química , Mananos/química , Mananos/farmacología , Galactosa/química , Galactosa/análogos & derivados , Humanos , Nanoconjugados/química , Concentración de Iones de Hidrógeno , Liberación de Fármacos , Línea Celular Tumoral , Portadores de Fármacos/química , Supervivencia Celular/efectos de los fármacos , Antibióticos Antineoplásicos/farmacología , Antibióticos Antineoplásicos/química , Antineoplásicos/química , Antineoplásicos/farmacología
11.
Int J Biol Macromol ; 268(Pt 1): 131661, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38641286

RESUMEN

In this study, two nanoemulsions were formulated with essential oil (EO) of Ocimum gratissimum with (EON) or without (EOE) cashew gum (CG). Subsequently, inhibition of melanosis and preservation of the quality of shrimp stored for 16 days at 4 ± 0.5 °C were evaluated. A computational approach was performed to predict the system interactions. Dynamic light scattering (DLS) and atomic force microscopy (AFM) were used for nanoparticle analysis. Gas chromatography and flame ionization detector (GC-FID) determined the chemical composition of the EO constituents. Shrimps were evaluated according to melanosis's appearance, psychrotrophic bacteria's count, pH, total volatile basic nitrogen, and thiobarbituric acid reactive substances. EON exhibited a particle size three times smaller than EOE. The shrimp treated with EON showed a more pronounced sensory inhibition of melanosis, which was considered mild by the 16th day. Meanwhile, in the other groups, melanosis was moderate (EOE) or severe (untreated group). Both EON and EOE treatments exhibited inhibition of psychrotrophic bacteria and demonstrated the potential to prevent lipid oxidation, thus extending the shelf life compared to untreated fresh shrimp. EON with cashew gum, seems more promising due to its physicochemical characteristics and superior sensory performance in inhibiting melanosis during shrimp preservation.


Asunto(s)
Anacardium , Ocimum , Aceites Volátiles , Animales , Aceites Volátiles/farmacología , Aceites Volátiles/química , Ocimum/química , Anacardium/química , Penaeidae/química , Gomas de Plantas/química , Conservación de Alimentos/métodos
12.
J Pharm Pharmacol ; 76(6): 732-742, 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38546507

RESUMEN

OBJECTIVES: Angico gum (AG) (Anadenanthera colubrina var. Cebil [Griseb.] Altschul) is utilized by some Brazilian communities to alleviate symptoms from gastroesophageal reflux disease. Here, we aimed to investigate the "in vitro" topical protective capacity of AG on human esophageal mucosa. METHODS: Biopsies of the distal esophageal mucosa were collected from 35 patients with heartburn (24 non-erosive and 11 with erosive oesophagitis (EE)) and mounted in Üssing chambers. AG was applied topically, followed by exposure with acid solution (pH 2.0 or pH 1.0), where transepithelial electrical resistance (TER) and The transepithelial permeability for fluorescein was assessed. The incubation of the AG labeled with FITC in the esophageal mucosa was localized by fluorescence microscopy. KEY FINDINGS: Pretreatment with AG prevented the drop in TER induced by acid solution, as well as significantly decreases the fluorescein permeability in non-erosive patients. The protective effect of AG was sustained for up to 120 min both in biopsies of non-erosive and erosive esophagitis. Confocal microscope images showed mucosal luminal adherence of FITC-labeled AG. CONCLUSION: AG had a prolonged topical protective effect against acid solution in mucosal biopsies of patients with non-erosive and erosive esophagitis.


Asunto(s)
Mucosa Esofágica , Reflujo Gastroesofágico , Humanos , Reflujo Gastroesofágico/tratamiento farmacológico , Reflujo Gastroesofágico/prevención & control , Mucosa Esofágica/efectos de los fármacos , Mucosa Esofágica/patología , Mucosa Esofágica/metabolismo , Masculino , Femenino , Persona de Mediana Edad , Adulto , Permeabilidad , Impedancia Eléctrica , Administración Tópica , Biopolímeros , Anciano , Fluoresceína/administración & dosificación , Esófago/efectos de los fármacos , Esófago/patología , Esófago/metabolismo , Pirosis/tratamiento farmacológico , Pirosis/prevención & control , Relevancia Clínica
13.
Int J Biol Macromol ; 274(Pt 2): 133048, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38857734

RESUMEN

Epiisopiloturine (EPI) is a compound found in jaborandi leaves with antiparasitic activity, which can be enhanced when incorporated into nanoparticles (NP). Cashew Gum (CG), modified by carboxymethylation, is used to produce polymeric nanomaterials with biological activity. In this study, we investigated the antimicrobial potential of carboxymethylated CG (CCG) NP containing EPI (NPCCGE) and without the alkaloid (NPCCG) against bacteria and parasites of the genus Leishmania. We conducted theoretical studies, carboxymethylated CG, synthesized NP by nanoprecipitation, characterized them, and tested them in vitro. Theoretical studies confirmed the stability of modified carbohydrates and showed that the EPI-4A30 complex had the best interaction energy (-8.47 kcal/mol). CCG was confirmed by FT-IR and presented DSabs of 0.23. NPCCG and NPCCGE had average sizes of 221.94 ± 144.086 nm and 247.36 ± 3.827 nm, respectively, with homogeneous distribution and uniform surfaces. No NP showed antibacterial activity or cytotoxicity to macrophages. NPCCGE demonstrated antileishmanial activity against L. amazonensis, both in promastigote forms (IC50 = 9.52 µg/mL, SI = 42.01) and axenic amastigote forms (EC50 = 6.6 µg/mL, SI = 60.60). The results suggest that nanostructuring EPI in CCG enhances its antileishmanial activity.


Asunto(s)
Anacardium , Antiinfecciosos , Nanopartículas , Gomas de Plantas , Anacardium/química , Nanopartículas/química , Gomas de Plantas/química , Antiinfecciosos/farmacología , Antiinfecciosos/química , Animales , Ratones , Leishmania/efectos de los fármacos , Simulación por Computador , Imidazoles , 4-Butirolactona/análogos & derivados
14.
Int J Biol Macromol ; 260(Pt 1): 129397, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38219933

RESUMEN

Biotechnological advancements require the physicochemical alteration of molecules to enhance their biological efficacy for the effective treatment of gastric ulcers. The study aimed to produce a polyelectrolytic compound from red angico gum (AG) by carboxymethylation, evaluate its physicochemical characteristics and investigate gastric protection against ethanol-induced ulcers. AG and carboxymethylated angico gum (CAG) were characterized by Fourier transform infrared spectroscopy, determination of the degree of substitution and gel permeation chromatography (GPC) and 13C NMR techniques. The results demonstrated that the modification of the polymer was satisfactory, presenting conformational changes e improving the interaction with the gastric mucosa. AG and CAG reduced macroscopic and microscopic damage such as edema, hemorrhage and cell loss caused by exposure of the mucosa to alcohol. Both demonstrated antioxidant activity in vitro, and in vivo, pretreatment with gums led to the restoration of superoxide dismutase and glutathione levels compared to the injured group. Concurrently, the levels of malondialdehyde and nitrite decreased. Atomic force microscopy showed that CAG presented better conformational properties of affinity and protection with the gastric mucosa compared to AG in the acidic pH. Based on our findings, it is suggested that this compound holds promise as a prospective product for future biotechnological applications.


Asunto(s)
Colubrina , Fabaceae , Úlcera Gástrica , Estudios Prospectivos , Estómago , Antioxidantes/efectos adversos , Mucosa Gástrica , Úlcera Gástrica/inducido químicamente , Úlcera Gástrica/tratamiento farmacológico , Extractos Vegetales/química
15.
Int J Mol Sci ; 14(3): 4969-81, 2013 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-23455467

RESUMEN

The present study describes the development of a green synthesis of silver nanoparticles reduced and stabilized by exuded gum from Anacardium occidentale L. and evaluates in vitro their antibacterial and cytotoxic activities. Characterization of cashew gum-based silver nanoparticles (AgNPs) was carried out based on UV-Vis spectroscopy, transmission electron microscopy and dynamic light scattering analysis which revealed that the synthesized silver nanoparticles were spherical in shape, measuring about 4 nm in size with a uniform dispersal. AgNPs presented antibacterial activity, especially against Gram-negative bacteria, in concentrations where no significant cytotoxicity was observed.

16.
Polymers (Basel) ; 15(11)2023 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-37299211

RESUMEN

The incorporation of polymeric components into aerogels based on clay produces a significant improvement in the physical and thermal properties of the aerogels. In this study, clay-based aerogels were produced from a ball clay by incorporation of angico gum and sodium alginate using a simple, ecologically acceptable mixing method and freeze-drying. The compression test showed a low density of spongy material. In addition, both the compressive strength and the Young's modulus of elasticity of the aerogels showed a progression associated to the decrease in pH. The microstructural characteristics of the aerogels were investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The chemical structure was studied by infrared spectroscopy with Fourier transform (FTIR). The TGA curves from a non-oxidizing atmosphere indicated that the clay had a mass loss of 9% above 500 °C and that due to the presence of polysaccharides, the aerogels presented a decomposition of 20% at temperatures above 260 °C. The DSC curves of the aerogels demonstrated a displacement in higher temperatures. In conclusion, the results showed that aerogels of ball clay with the incorporation of polysaccharides, which are still minimally studied, have potential application as thermal insulation considering the mechanical and thermal results obtained.

17.
Int J Biol Macromol ; 243: 125254, 2023 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-37295699

RESUMEN

The present work explores the esterification reaction in the polysaccharide extracted from the seaweed Gracilaria birdiae and investigates its antioxidant potential. The reaction process was conducted with phthalic anhydride at different reaction times (10, 20 and 30 min), using a molar ratio of 1:2 (polymer: phthalic anhydride). Derivatives were characterized by FTIR, TGA, DSC and XRD. The biological properties of derivatives were investigated by assays of cytotoxicity and antioxidant activity (2,2-diphenyl-1-picrylhydroxyl - DPPH and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt - ABTS). The results obtained by FT-IR confirmed the chemical modification, there was a reduction related to the presence of carbonyl and hydroxyl groups when compared to the in nature polysaccharide spectrum. TGA analysis showed a change in the thermal behavior of the modified materials. X-ray diffraction, it was shown that the in nature polysaccharide appeared as an amorphous material, while the material obtained after the chemical modification process had increased crystallinity, due to the introduction of phthalate groups. For the biological assays, it was observed that the phthalate derivative was more selective than the unmodified material for the murine metastatic melanoma tumor cell line (B16F10), revealing a good antioxidant profile for DPPH and ABTS radicals.


Asunto(s)
Antineoplásicos , Gracilaria , Animales , Ratones , Antioxidantes/química , Anhídridos Ftálicos , Galactanos , Espectroscopía Infrarroja por Transformada de Fourier , Antineoplásicos/química , Polisacáridos/química
18.
Polymers (Basel) ; 15(13)2023 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-37447501

RESUMEN

Tree-exuded gums are natural polymers that represent an abundant raw material in the food and pharmaceutical industries. The cashew gum can be obtained by exudation of trees of the genus Anacardium, a native species of the Brazilian northeast; its polymer consists of monosaccharide units propitious to the action of chemical reactions that tend to improve their intrinsic characteristics among them, as the degree of hydro-solubility. The objective of this work was to modify the exudate gum of Anacardium occidentale (cashew gum (CG)) through an amine reaction. The modification was confirmed by Nuclear Magnetic Resonance (1H NMR), infrared spectroscopy (FTIR), gel permeation chromatography (GPC), zeta potential, and thermogravimetric analysis (TG). In addition, the chemical modification altered the molar mass and surface charge of the CG, and the amino group binding to the CG polymers was confirmed by FTIR spectra. In addition, cytotoxicity tests were performed where cell viability was estimated by an MTT assay on RAW 264.7 macrophages. Through these tests, it was found that the amine caused an increase in the thermal stability of the amino compounds and did not present cytotoxic potential at concentrations below 50.0 mg/L.

19.
Int J Biol Macromol ; 253(Pt 6): 127281, 2023 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-37806422

RESUMEN

Hydrogels made with depolymerized guar gum, oxidized with theoretical oxidation degrees of 20, 35 and 50 %, were obtained via Schiff's base reaction with N-succinyl chitosan. The materials obtained were subjected to characterization by FT-IR, rheology, swelling, degradation, and morphology. Additionally, their gelation time categorized all three hydrogels as injectable. The materials' swelling degrees in Phosphate-Buffered Saline (PBS) were in the range of 26-35 g of fluid/g gel and their pore size distribution was heterogeneous, with pores varying from 67 to 93 µm. All hydrogels degraded in PBS solution, but maintained around 40 % of their initial mass after 28 days, which was more than enough time for wound healing. The biomaterials were also flexible, self-repairing, adhesive and cytocompatible and presented intrinsic actions, regardless of the presence of additives or antibiotics, against gram-positive (Staphylococcus aureus, Staphylococcus epidermidis) and gram-negative bacteria (Escherichia coli). However, the most pronounced bactericidal effect was against resistant Staphylococcus aureus - MRSA. In vivo assays, performed with 50 % oxidized gum gel, demonstrated that this material exerted anti-inflammatory effects, accelerating the healing process and restoring tissues by approximately 99 % within 14 days. In conclusion, these hydrogels have unique characteristics, making them excellent candidates for wound-healing dressings.


Asunto(s)
Quitosano , Staphylococcus aureus Resistente a Meticilina , Hidrogeles/farmacología , Quitosano/farmacología , Espectroscopía Infrarroja por Transformada de Fourier , Vendajes , Bacterias , Antibacterianos/farmacología , Staphylococcus aureus
20.
Laryngoscope ; 133(1): 162-168, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-35258096

RESUMEN

OBJECTIVE: This study aimed to evaluate the in vivo protective effect of the angico gum biopolymer in reducing the inflammatory response and preserving the integrity of the laryngeal and esophageal mucosa. STUDY DESIGN: Animal study. METHODS: A murine surgical model of gastroesophageal reflux disease was accomplished and subsequently treated with angico gum or omeprazole. On days 3 and 7 post surgery, samples of the larynx and esophagus, respectively, were collected to measure the level of inflammation (wet weight and myeloperoxidase activity) and mucosal integrity (transepithelial electrical resistance and mucosal permeability to fluorescein). RESULTS: Angico gum and omeprazole decreased laryngeal inflammation (wet weight and myeloperoxidase activity) and dramatically improved the integrity of the laryngeal mucosa. It also reduced inflammation (decreased wet weight and myeloperoxidase activity) of the esophagus and preserved the barrier function (inferred by assessing the integrity of the mucosa). CONCLUSION: This study demonstrates the protective effect of angico gum in an experimental gastroesophageal reflux disease model. Angico gum attenuates inflammation and impairment of the mucosal barrier function not only in the larynx but also in the esophagus. LEVEL OF EVIDENCE: NA Laryngoscope, 133:162-168, 2023.


Asunto(s)
Mucosa Esofágica , Reflujo Gastroesofágico , Ratones , Animales , Reflujo Gastroesofágico/tratamiento farmacológico , Impedancia Eléctrica , Membrana Mucosa , Modelos Animales de Enfermedad
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA