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1.
Photodiagnosis Photodyn Ther ; 38: 102801, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35288323

RESUMO

BACKGROUND/AIMS: Silica nanoparticles (SiNPs) have been promising vehicles for drug delivery. Cichorium Pumilum (CP), a natural photosensitizer (PS), has been reported to have many useful effects in cancer treatment. However, the poor water solubility and its low bioavailability have confined its use as a suitable photosensitizer for photodynamic therapy. Therefore, a subtle approach is required to overcome these drawbacks. MATERIALS AND METHODS: We have synthesized a silica nanoparticles loaded with Cichorium Pumilum. The nanoparticles structural morphologies have been charectrized by Transmission Electron Microscopy (TEM). The cytotoxicity for different concentrations of naked and encapsulated CP was evaluated. Moreover, the optimal concentration of naked and encapsulated CP with exposure time to a light (Maximum intensity at 350nm ∼0.27mW/cm2) required to eliminate the used cells (Osteosarcoma cells) were also measured. RESULTS: The results showed that encapsulated CP in SiNPs exhibited relatively higher efficacy than the naked CP by + 157.14 % of exposure time efficacy and + 49.45% of concentration efficacy, and encapsulated CP was also confirmed to be effective in eradicating osteosarcoma cells. CONCLUSION: The engineered silica nanoparticles loaded with CP enhanced the photodynamic therapy by increasing the CP bioavailability.


Assuntos
Asteraceae , Neoplasias Ósseas , Nanopartículas , Osteossarcoma , Fotoquimioterapia , Humanos , Nanopartículas/química , Osteossarcoma/tratamento farmacológico , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes , Dióxido de Silício/química
2.
Appl Radiat Isot ; 130: 49-53, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28942328

RESUMO

Radon is one of the sources that negatively affect dwellings air quality and is ranked as a main cause of lung cancer after cigarette smoking. The indoor radon concentrations usually affected by the conditions of the environment surrounding the dwellings. Seasonal variations can have a significant impact on the indoor radon concentrations. In this article, we studied the seasonal variations of indoor radon concentration in a desert climate, particularly in gulf countries that usually leave the windows and doors closed all over the time. Four hundred dosimeters containing CR-39 detectors were planted for three months to measure the variation in radon concentration between winter and summer seasons. Our measurements showed that a building with a basement revealed a significant variation between radon concentration in winter (44.3 ± 3.1Bqm-3) and in summer (26.1 ± 1.7Bqm-3). Buildings without basements showed that the indoor radon concentration in winter (16.1 ± 1.7Bqm-3) is very much close to that in summer (16.7 ± 1.8Bqm-3). Our results indicated that seasonal variations can significantly affect indoor radon concentration for buildings established with basements. However; in the study region, the average indoor radon concentration as well as the annual effective dose rate are found to be below the action level recommended by ICRP.


Assuntos
Poluentes Radioativos do Ar/análise , Poluição do Ar em Ambientes Fechados/análise , Clima Desértico , Habitação , Radônio/análise , Estações do Ano , Dosímetros de Radiação
3.
Photodiagnosis Photodyn Ther ; 18: 111-118, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28232076

RESUMO

BACKGROUND: Iron oxide (Fe3O4) nanoparticles (IO-NP) were recently employed in medical applications as a diagnostic tool and drug carrier. Photofrin (PF) is a photosensitizer that clinically is used in Photodynamic therapy (PDT). STUDY DESIGN: The photosensitivity of PF and Rose Bengal (RB) mixed with (IO-NP) on red blood cells (RBCs) lysis was investigated. Second, Photohemolysis for post-irradiation (delayed) and during irradiation (continuous) with PF, RB and IO-NP combinations at different concentrations was investigated. Third, the photohemolysis rate, relative lysis steepness and power-concentration dependant parameter were evaluated by modeling and fitting the data using Gompertz function and power law. METHODS: RBCs were isolated from healthy male human volunteer. Washed cells (7.86×106 cells/mm3) were incubated with PF only or with IO-NP for 45min at 37°C then irradiated to a range of temperatures (4-41°C). CPH results were recorded and evaluated using Gompertz function. RESULTS: The relative steepness of the photohemolysis curves was approximately independent on light dose for delayed irradiation. The presence of IO-NP increases the rupturing time for 50% of the RBCs. Photohemolysis rate for delayed irradiation using the power law, led to 1.7 and 2.3 power dependence, respectively, for PF only and PF mixed with IO-NP. The power dependence of continuous irradiation measurements showed inverse proportionality for different concentrations of IO-NP combined with 2µg/ml PF concentration and 1.5µg/ml for RB concentration. CONCLUSION: Photosensitization of RBC with PF or RB mixed with IO-NP inhibited rupturing erythrocyte membrane and therefore a consideration should be taken against their combination in clinical applications.


Assuntos
Dextranos/administração & dosagem , Éter de Diematoporfirina/administração & dosagem , Eritrócitos/efeitos dos fármacos , Eritrócitos/efeitos da radiação , Hemólise/efeitos dos fármacos , Hemólise/efeitos da radiação , Nanopartículas de Magnetita/administração & dosagem , Fotoquimioterapia/métodos , Rosa Bengala/administração & dosagem , Adulto , Células Cultivadas , Relação Dose-Resposta a Droga , Relação Dose-Resposta à Radiação , Combinação de Medicamentos , Eritrócitos/fisiologia , Hemólise/fisiologia , Humanos , Masculino , Nanocápsulas/administração & dosagem , Fármacos Fotossensibilizantes/administração & dosagem
4.
Artif Cells Nanomed Biotechnol ; 45(4): 843-853, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27137748

RESUMO

Curcumin is more soluble in ethanol, dimethylsulfoxide, methanol and acetone than in water. In this study, nanocurcumin combined with 8 mT AC static magnetic field was used to enhance cellular uptake, bioavailability, and ultimate efficiency of curcumin against prostate cancer cell line (PC3), four bacteria strains (two Gram positive: Micrococcus luteus ATCC 9341, Staphylococcus aureus ATCC 29213 and two Gram negative: Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853), mammalian cell line (HEK) and human erythrocytes (RBC). The efficiency (E%) between IC50 of nanocurcumin combined with magnetic field (NANOCUR-MF) and control against PC3 was 35.93%, which is three times higher compared to curcumin combined with magnetic field (CUR-MF); i.e., 10.77%. However, their E% against HEK was not significant; 1.4% for NANOCUR-MF and 1.95% for CUR-MF. Moreover, depending in minimum bacterial concentration (MBC), the use of MF leads to a reduction of MBCs for all tested bacteria compared with control. The obtained results established the applicability of (MF) in enhancing cellular uptake for PC3 and tested bacteria strains by increasing the penetration of drug (nanocurcumin and parent curcumin) into cell with fixing mild cytotoxic profile for HEK and RBC.


Assuntos
Bactérias/efeitos dos fármacos , Curcumina/química , Curcumina/farmacologia , Campos Magnéticos , Nanopartículas/química , Neoplasias da Próstata/patologia , Antibacterianos/química , Antibacterianos/metabolismo , Antibacterianos/farmacocinética , Antibacterianos/farmacologia , Antineoplásicos/química , Antineoplásicos/metabolismo , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Disponibilidade Biológica , Transporte Biológico , Linhagem Celular Tumoral , Permeabilidade da Membrana Celular , Curcumina/metabolismo , Curcumina/farmacocinética , Eritrócitos/efeitos dos fármacos , Humanos , Masculino
5.
Electromagn Biol Med ; 31(4): 299-309, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22812448

RESUMO

Cichorium Pumilum (chicory) is could be a promising cancer treatment in which a photosensitizing drug concentrates in benign tumor cells and activated by quanta at certain wavelength. Such activated extracts could lead to cell death and tumor ablation. Previous studies have shown that Cichorium Pumilum (chicory) contains photosensitive compounds such as cichoriin, anthocyanins, lactucin, and Lactucopicrin. In the present study, the protective effect of sun light-activated Cichorium against the dimethylbenz[a]anthracene (DMBA) induced benign breast tumors to female Sprague-Dawley rats was investigated. Chicory's extract has significantly increase P.carbonyl (PC) and malondialdehyde (MDA) and decreases the hepatic levels of total antioxidant capacity (TAC) and superoxide dismutase (SOD) in benign breast tumors-induced group compared to control. It also significantly decrease the number of estrogen receptors ER-positive cells in tumor masses. These results suggest that chicory extracts could be used as herbal photosensitizing agent in treating benign breast tumor in rats.


Assuntos
Antineoplásicos/farmacologia , Asteraceae/química , Neoplasias Mamárias Experimentais/induzido quimicamente , Neoplasias Mamárias Experimentais/tratamento farmacológico , Fármacos Fotossensibilizantes/farmacologia , Extratos Vegetais/farmacologia , Animais , Antineoplásicos/uso terapêutico , Antioxidantes/metabolismo , Catalase/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Peroxidação de Lipídeos/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos da radiação , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/efeitos da radiação , Neoplasias Mamárias Experimentais/metabolismo , Neoplasias Mamárias Experimentais/patologia , Fármacos Fotossensibilizantes/uso terapêutico , Extratos Vegetais/uso terapêutico , Ratos , Ratos Sprague-Dawley , Receptores de Estrogênio/metabolismo , Superóxido Dismutase/metabolismo
6.
World J Surg Oncol ; 10: 62, 2012 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-22533492

RESUMO

BACKGROUND: Resistance of breast cancer cells to the available chemotherapeutics is a major obstacle to successful treatment. Recent studies have shown that magnetic nanoparticles might have significant application in different medical fields including cancer treatment. The goal of this study is to verify the ability of magnetic nanoparticles to sensitize cancer cells to the clinically available chemotherapy. METHODS: The role of iron oxide nanoparticles, static magnetic field, or a combination in the enhancement of the apoptotic potential of doxorubicin against the resistant breast cancer cells, MCF-7 was evaluated using the MTT assay and the propidium iodide method. RESULTS: In the present study, results revealed that pre-incubation of MCF-7 cells with iron oxide nanoparticles before the addition of doxorubicin did not enhance doxorubicin-induced growth inhibition. Pre-incubation of MCF-7 cells with iron oxide nanoparticles followed by a static magnetic field exposure significantly (P < 0.05) increased doxorubicin-induced cytotoxicity. Sensitization with pre-exposure to the magnetic field was dose-dependent where the highest cytotoxicity was seen at 1 tesla. Further experiments revealed that the anti-proliferative effect of this treatment procedure is due to induction of apoptotic cell death. CONCLUSIONS: These results might point to the importance of combining magnetic nanoparticles with a static magnetic field in treatment of doxorubicin-refractory breast cancer cells.


Assuntos
Apoptose/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Doxorrubicina/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Magnetismo , Nanopartículas Metálicas/uso terapêutico , Feminino , Compostos Férricos/química , Humanos , Células Tumorais Cultivadas
7.
J Pharm Bioallied Sci ; 3(2): 266-76, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21687357

RESUMO

BACKGROUND: A new approach for evaluating the optical penetration depth and testing its validity with Monte Carlo simulations and Kubelka-Munk theory is used for artificial semi-rigid tissue sensitized with natural pigments. Photodynamic therapy is a promising cancer treatment in which a photosensitizing drug concentrates in malignant cells and is activated by visible light at certain wavelength. MATERIALS AND METHODS: Cheap artificial semi-rigid tissue incorporated with scattering and absorbing materials along with some other composites comparable to normal human tissue has been performed. The optical parameters as measured with different conditions and calculated with various techniques are investigated. RESULTS: The probability of interaction of light with tissue is very high when exposed to light in presence of Cichorium pumilum and RBCs followed by photohemolysis or/and photodegradation. The optical penetration depth calculated by linear absorption coefficient ranges from 0.63 to 2.85 mm is found to be comparable to those calculated using Kubelka-Munk theory or Monte Carlo simulation (range from 0.78 to 2.42 mm). The ratio of absorption to the scattering is independent of thickness and decreases with increasing irradiation time. Moreover, the optical parameters as well as their ratios are in very good agreement in the two approaches of calculation. The values of absorption and scattering coefficients are independent of thickness. Furthermore, the average photon ranges in the samples containing no scattering and absorbing materials are about three times greater than those samples containing scattering materials. CONCLUSION: Our results suggest that light propagation with optical properties presented in this work could be applicable in diagnostic and therapeutic of the human biological tissue for photodynamic therapy.

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