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1.
Biochem Biophys Rep ; 35: 101492, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37304131

RESUMO

Cancer treatment typically involves multiple strategies, such as surgery, radiotherapy, and chemotherapy, to remove tumors. However, chemotherapy often causes side effects, and there is a constant search for new drugs to alleviate them. Natural compounds are a promising alternative to this problem. Indole-3-carbinol (I3C) is a natural antioxidant agent that has been studied as a potential cancer treatment. I3C is an agonist of the aryl hydrocarbon receptor (AhR), a transcription factor that plays a role in the expression of genes related to development, immunity, circadian rhythm, and cancer. In this study, we investigated the effect of I3C on cell viability, migration, invasion properties, as well as mitochondrial integrity in hepatoma, breast, and cervical cancer cell lines. We found that all tested cell lines showed impaired carcinogenic properties and alterations in mitochondrial membrane potential after treatment with I3C. These results support the potential use of I3C as a supplementary treatment for various types of cancer.

2.
Cell Mol Biol (Noisy-le-grand) ; 67(1): 73-79, 2021 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-34817365

RESUMO

Xanthan gum (XG) and polyvinylpyrrolidone (PVP) are two polymers with low toxicity, high biocompatibility, biodegradability, and high hydrophilicity, making them promising candidates for multiple medical aspects. The present work aimed to synthesize a hydrogel from a mixture of XG and PVP and crosslinked by gamma irradiation. We assessed the hydrogel through a series of physicochemical (FT-IR, TGA, SEM, and percentage of swelling) and biological (stability of the hydrogel in cell culture medium) methods that allowed to determine its applicability. The structural evaluation by infrared spectrum demonstrated that a crosslinked hydrogel was obtained from the combination of polymers. The calorimetric test and swelling percentage confirmed the formation of the bonds responsible for the crosslinked structure. The calorimetric test evidenced that the hydrogel was resistant to decomposition in contrast to non- irradiated material. The determination of the swelling degree showed constant behavior over time, indicating a structure resistant to hydrolysis. This phenomenon also occurred during the test of stability in a cell culture medium. Additionally, microscopic analysis of the sample revealed an amorphous matrix with the presence of porosity. Thus, the findings reveal the synthesis of a novel material that has desirable attributes for its potential application in pharmaceutical and biomedical areas.


Assuntos
Raios gama , Hidrogéis/efeitos da radiação , Polímeros/efeitos da radiação , Polissacarídeos Bacterianos/efeitos da radiação , Povidona/efeitos da radiação , Hidrogéis/síntese química , Hidrogéis/química , Microscopia Eletrônica de Varredura , Modelos Químicos , Estrutura Molecular , Polímeros/síntese química , Polímeros/química , Polissacarídeos Bacterianos/síntese química , Polissacarídeos Bacterianos/química , Porosidade , Povidona/síntese química , Povidona/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Temperatura , Termogravimetria/métodos
3.
Cell Mol Biol (Noisy-le-grand) ; 67(1): 64-72, 2021 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-34817366

RESUMO

The purpose of our study was to obtain new wound dressings in the form of hydrogels that promote wound healing taking advantage of the broad activities of elastin (ELT) in physiological processes. The hydrogel of ELT and polyvinylpyrrolidone (PVP; ELT-PVP) was obtained by cross-linking induced by gamma irradiation at a dose of 25 kGy. The physicochemical changes attributed to cross-linking were analyzed through scanning electron microscopy (SEM), infrared spectroscopy analysis with Fourier transform (FTIR), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). Furthermore, we performed a rheological study to determine the possible changes in the fluidic macroscopic properties produced by the cross-linking method. Finally, we accomplished viability and proliferation analyses of human dermal fibroblasts in the presence of the hydrogel to evaluate its biological characteristics. The hydrogel exhibited a porous morphology, showing interconnected porous with an average pore size of 16 ± 8.42 µm. The analysis of FTIR, DSC, and TGA revealed changes in the chemical structure of the ELT-PVP hydrogel after the irradiation process. Also, the hydrogel exhibited a rheological behavior of a pseudoplastic and thixotropic fluid. The hydrogel was biocompatible, demonstrating high cell viability, whereas ELT presented low biocompatibility at high concentrations. In summary, the hydrogel obtained by gamma irradiation revealed the appropriate morphology to be applied as a wound dressing. Interestingly, the hydrogel exhibited a higher percentage of cell viability compared with ELT, suggesting that the cross-linking of ELT with PVP is a suitable strategy for biological applications of ELT without generating cellular damage.


Assuntos
Materiais Biocompatíveis/metabolismo , Elastina/metabolismo , Curativos Oclusivos , Polimerização/efeitos da radiação , Povidona/metabolismo , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Varredura Diferencial de Calorimetria/métodos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Elastina/química , Elastina/ultraestrutura , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Humanos , Hidrogéis/química , Hidrogéis/metabolismo , Hidrogéis/farmacologia , Microscopia Eletrônica de Varredura , Povidona/química , Povidona/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Termogravimetria/métodos , Cicatrização/efeitos dos fármacos
4.
Molecules ; 26(7)2021 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-33916823

RESUMO

Nanoparticles possess a huge potential to be employed in numerous biomedical purposes; their applications may include drug delivery systems, gene therapy, and tissue engineering. However, the in vivo use in biomedical applications requires that nanoparticles exhibit sterility. Thus, diverse sterilization techniques have been developed to remove or destroy microbial contamination. The main sterilization methods include sterile filtration, autoclaving, ionizing radiation, and nonionizing radiation. Nonetheless, the sterilization processes can alter the stability, zeta potential, average particle size, and polydispersity index of diverse types of nanoparticles, depending on their composition. Thus, these methods may produce unwanted effects on the nanoparticles' characteristics, affecting their safety and efficacy. Moreover, each sterilization method possesses advantages and drawbacks; thus, the suitable method's choice depends on diverse factors such as the formulation's characteristics, batch volume, available methods, and desired application. In this article, we describe the current sterilization methods of nanoparticles. Moreover, we discuss the advantages and drawbacks of these methods, pointing out the changes in nanoparticles' biological and physicochemical characteristics after sterilization. Our main objective was to offer a comprehensive overview of terminal sterilization processes of nanoparticles for biomedical applications.


Assuntos
Tecnologia Biomédica , Nanopartículas/química , Esterilização , Filtração , Radiação Ionizante
5.
Membranes (Basel) ; 10(9)2020 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-32872576

RESUMO

The blood-brain barrier (BBB) is a sophisticated and very selective dynamic interface composed of endothelial cells expressing enzymes, transport systems, and receptors that regulate the passage of nutrients, ions, oxygen, and other essential molecules to the brain, regulating its homeostasis. Moreover, the BBB performs a vital function in protecting the brain from pathogens and other dangerous agents in the blood circulation. Despite its crucial role, this barrier represents a difficult obstacle for the treatment of brain diseases because many therapeutic agents cannot cross it. Thus, different strategies based on nanoparticles have been explored in recent years. Concerning this, chitosan-decorated nanoparticles have demonstrated enormous potential for drug delivery across the BBB and treatment of Alzheimer's disease, Parkinson's disease, gliomas, cerebral ischemia, and schizophrenia. Our main objective was to highlight the high potential of chitosan adsorption to improve the penetrability through the BBB of nanoformulations for diseases of CNS. Therefore, we describe the BBB structure and function, as well as the routes of chitosan for crossing it. Moreover, we define the methods of decoration of nanoparticles with chitosan and provide numerous examples of their potential utilization in a variety of brain diseases. Lastly, we discuss future directions, mentioning the need for extensive characterization of proposed nanoformulations and clinical trials for evaluation of their efficacy.

6.
Cell Mol Biol (Noisy-le-grand) ; 66(4): 199-207, 2020 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-32583796

RESUMO

Controlled release is of vital relevance for many drugs; thus, there is a keen interest in materials that can improve the release profiles of formulations administered via buccal, transdermal, ophthalmic, vaginal, and nasal. The desirable effects of those materials include the improvement of stability, adhesiveness, solubility, and retention time. Hence, different synthetic and natural polymers are utilized to achieve these objectives. In this respect, xanthan gum is an anionic polysaccharide that can be obtained from Xanthomonas bacteria. It is a natural polymer broadly employed in numerous food products, lotions, shampoos, and dermatological articles. Furthermore, due to its physicochemical features, xanthan gum is growingly utilized for the development and improvement of drug delivery systems. In this regard, encouraging findings have been revealed by recent formulations for pharmaceutical applications, including antiviral carriers, antibacterial transporters, transdermal patches, vaginal formulations, and anticancer medications. In this article, we perform a concise description of the chemical properties of xanthan gum and its role as a modifier of drug release. Furthermore, we present an outlook of the state of the art of research focused on the utilization of xanthan gum in varied pharmaceutical formulations, which include tablets, films, hydrogels, and nanoformulations. Finally, we discuss some perspectives about the use of xanthan gum in these formulations.


Assuntos
Liberação Controlada de Fármacos , Polissacarídeos Bacterianos/química , Animais , Preparações de Ação Retardada , Formas de Dosagem , Humanos , Hidrogéis/química , Nanopartículas/química
7.
Front Oncol ; 10: 605714, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33489912

RESUMO

Skin cancers are highly prevalent malignancies that affect millions of people worldwide. These include melanomas and nonmelanoma skin cancers. Melanomas are among the most dangerous cancers, while nonmelanoma skin cancers generally exhibit a more benign clinical pattern; however, they may sometimes be aggressive and metastatic. Melanomas typically appear in body regions exposed to the sun, although they may also appear in areas that do not usually get sun exposure. Thus, their development is multifactorial, comprising endogenous and exogenous risk factors. The management of skin cancer depends on the type; it is usually based on surgery, chemotherapy, immunotherapy, and targeted therapy. In this respect, oncological treatments have demonstrated some progress in the last years; however, current therapies still present various disadvantages such as little cell specificity, recurrent relapses, high toxicity, and increased costs. Furthermore, the pursuit of novel medications is expensive, and the authorization for their clinical utilization may take 10-15 years. Thus, repositioning of drugs previously approved and utilized for other diseases has emerged as an excellent alternative. In this mini-review, we aimed to provide an updated overview of drugs' repurposing to treat skin cancer and discuss future perspectives.

8.
J Cancer ; 7(13): 1856-1860, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27698925

RESUMO

Chromatin in cervical cancer (CC) undergoes chemical and structural changes that alter the expression pattern of genes. Recently, a potential mechanism, which regulates gene expression at transcriptional levels is the proteolytic clipping of histone H3. However, until now this process in CC has not been reported. Using HeLa cells as a model of CC and human samples from patients with CC, we identify that the H3 cleavage was lower in CC compared with control tissue. Additionally, the histone H3 clipping was performed by serine and aspartyl proteases in HeLa cells. These results suggest that histone H3 clipping operates as part of post-translational modification system in CC.

9.
BMC Musculoskelet Disord ; 17: 79, 2016 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-26875674

RESUMO

BACKGROUND: FBN1 (15q21.1) encodes fibrillin-1, a large glycoprotein which is a major component of microfibrils that are widely distributed in structural elements of elastic and non-elastic tissues. FBN1 variants are responsible for the related connective tissue disorders, grouped under the generic term of type-1 fibrillinopathies, which include Marfan syndrome (MFS), MASS syndrome (Mitral valve prolapse, Aortic enlargement, Skin and Skeletal findings, Acromicric dysplasia, Familial ectopia lentis, Geleophysic dysplasia 2, Stiff skin syndrome, and dominant Weill-Marchesani syndrome. CASE PRESENTATION: Two siblings presented with isolated skeletal manifestations of MFS, including severe pectus excavatum, elongated face, scoliosis in one case, and absence of other clinical features according to Ghent criteria diagnosis, were screened for detection of variants in whole FBN1 gene (65 exons). Both individuals were heterozygous for the R2726W variant. This variant has been previously reported in association with some skeletal features of Marfan syndrome in the absence of both tall stature and non-skeletal features. These features are consistent with the presentation of the siblings reported here. CONCLUSION: The presented cases confirm that the R2726W FBN1 variant is associated with skeletal features of MFS in the absence of cardiac or ocular findings. These findings confirm that FBN1 variants are associated with a broad phenotypic spectrum and the value of sequencing in atypical cases.


Assuntos
Variação Genética/genética , Heterozigoto , Síndrome de Marfan/diagnóstico , Síndrome de Marfan/genética , Proteínas dos Microfilamentos/genética , Irmãos , Adolescente , Doenças do Desenvolvimento Ósseo/diagnóstico , Doenças do Desenvolvimento Ósseo/genética , Feminino , Fibrilina-1 , Fibrilinas , Humanos , Masculino , Linhagem
10.
PLoS One ; 9(6): e99974, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24924803

RESUMO

Levels of enzymes that determine testosterone catabolism such as CYP3A4 have been associated with prostate cancer (PCa) risk. Although some studies have related CYP3A4*1B allele, a gene polymorphism that modifies CYP3A4 expression level, with PCa risk, others have failed, suggesting that additional genetic variants may be involved. Expression of CYP3A4 is largely due to the activation of Pregnane X Receptor (PXR). Particularly, rs2472677 and rs7643645 PXR polymorphisms modify CYP3A4 expression levels. To evaluate whether PXR-HNF3ß/T (rs2472677), PXR-HNF4/G (rs7643645), and CYP3A4*1B (rs2740574) polymorphisms are associated with PCa a case control-study was performed. The multiple testing analysis showed that the PXR-HNF4/G polymorphism was associated with higher levels of prostate-specific antigen (PSA) in patients with PCa (OR = 3.99, p = 0.03). This association was stronger in patients diagnosed at the age of 65 years or older (OR = 10.8, p = 0.006). Although the CYP3A4*1B/*1B genotype was overrepresented in PCa patients, no differences were observed in the frequency of this and PXR-HNF3ß/T alleles between controls and cases. Moreover, no significant association was found between these polymorphisms and PSA, Gleason grade, or tumor lymph node metastasis.


Assuntos
Calicreínas/sangue , Polimorfismo de Nucleotídeo Único , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/sangue , Neoplasias da Próstata/genética , Receptores de Esteroides/genética , Idoso , Alelos , Estudos de Casos e Controles , Citocromo P-450 CYP3A/genética , Citocromo P-450 CYP3A/metabolismo , Regulação Enzimológica da Expressão Gênica/genética , Regulação Neoplásica da Expressão Gênica , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Receptor de Pregnano X , Neoplasias da Próstata/patologia , Fatores de Risco , Regulação para Cima
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