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1.
Burns ; 48(1): 146-155, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34686391

RESUMO

In this research, a novel semi-interpenetrating hydrogel network comprised of polyethylene glycol diacrylate (PEGDA)/polyvinyl alcohol (PVA)/tragacanth gum (TG) with adaptable mechanical, biological, and physical characteristics was fabricated for wound healing purposes. The chemical structure of the films and the surface morphology were examined by FTIR and SEM, respectively. In addition, swelling ratio, mechanical characteristics, water vapor transmission rate (WVTR), gel fraction, and degradability of the hydrogels were assessed. To evaluate their cytocompatibility, MTT assay and cell attachment studies were performed. The FTIR results showed that the vinyl peaks were eliminated during crosslinking between PEGDA chains. The results also showed that incorporating PVA into the networks increases the swelling ration and decreases the porosity. Furthermore, as the ratio of PEGDA to PVA increased, WVTR ratio, cell adhesion, and elongation of the networks increased. It was also found that, when the amount of PEGDA reduced, degradation rate of the networks decreased. The results verified the non-toxic nature of PEGDA/PVA/TG hydrogel networks. Finally, the antibacterial results demonstrated that the highest antibacterial activities against bacterial pathogens is related to the TG-containing film. Therefore, PEGDA/PVA/TG hydrogel networks can be favorable wound dressings.


Assuntos
Queimaduras , Tragacanto , Bandagens/microbiologia , Queimaduras/terapia , Humanos , Hidrogéis , Polietilenoglicóis , Álcool de Polivinil/química
2.
Microb Pathog ; 141: 103986, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31972270

RESUMO

Biofilms are organized communities, adherent to the surface and resistant to adverse environmental and antimicrobial agents. So, its control is very important. Staphylococcus aureus is an opportunistic pathogen with the biofilm-forming ability that causes numerous problems in the medicine and food industry. Therefore, this study aimed to investigate the effect of pH, ethanol and NaCl concentrations after 24 and 48 h incubation times at 37 °C, also modeling the results with artificial neural network (ANN). For this purpose, after both incubation times, the effect of each parameter was studied, separately and also in combination at the levels in which the highest biofilm was formed. All results were modeled using multiple ANN and compared in terms of R-value and MSE. The highest biofilm formation ability was in neutral pH. Adding the ethanol and NaCl stimulated biofilm formation, but the inhibitory effect was observed at high concentrations of ethanol and NaCl and very acidic or highly alkaline pH levels. The more incubation time also led to an increase in biofilm formation. Eventually, the Feed-Forward, Back-Propagation Neural Network model with the Levenberg-Marquardt training algorithm and 4-12-1 topology was chosen (R-value = 0.995 and validation MSE = 0.011467). This ANN had high modeling ability because there was a high correlation between experimental data and modeling data. Therefore, it was concluded that pH, ethanol, NaCl, and time are effective parameters in the biofilm formation and there is a nonlinear relationship between these factors that the ANN is capable of modeling them.


Assuntos
Biofilmes/efeitos dos fármacos , Etanol/farmacologia , Concentração de Íons de Hidrogênio , Redes Neurais de Computação , Cloreto de Sódio/farmacologia , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/fisiologia , Algoritmos
3.
BMC Chem ; 13(1): 80, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31384827

RESUMO

BACKGROUND: Ursolic acid (UA) is an important bioactive component in many traditional medicinal plants including pomegranate (Punica granatum L.) flower. METHODS: This study presents the HPLC analysis of UA contents of ten cultivars of pomegranate flower grown in Iran. The UA contents of fallen flowers of pomegranate were given in each cultivar. RESULTS: Remarkable quantities of UA were found in ten cultivars of Iranian pomegranate flower evaluated (21.736 to 15.119 mg/g). Lower quantities of UA were determined in pomegranate fallen flowers (16.763 to 5.754 mg/g). CONCLUSION: UA values obtained from Iranian cultivars of pomegranate flowers are very significant when compared with other sources of UA. All of the analyzes suggested that the Iranian pomegranate flowers (including flowers on branches and fallen flowers) might be an excellent UA rich source.

4.
J Biomed Mater Res A ; 106(9): 2463-2471, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29664223

RESUMO

Current studies based on regenerative medicine suggest, decellularized extracellular matrix (DC-ECM) components can regulate cell phenotype. In this regard, it is believed, presence of cartilage extracellular matrix particles in culture condition could produce physical and biochemical supportive cues for chondrogenesis. In this study, DC-ECM nanoparticles with average size of 61.5± 22.4 nm were produced by decellularization and mechanical processing. Homogenous distribution and nanoscale size of yield particles were observed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) microscopy imaging. Chemical structure preservation of cartilage ECM after decellularization was also confirmed by typical Fourier transform infrared (FTIR) spectrum mapping. The influence these nanoparticles on chondrogenic response of chondrocyte cells was investigated by direct and indirect addition of nanoparticles to culture medium. A clinical devitalized cartilage powder (DV-ECM) was also used as a positive control. Totally, MTS results showed that direct and indirect presence of both DC-ECM and DV-ECM particles in culture medium enhanced cellular metabolic activity except on day one of culture. Furthermore, on day 21, SOX9 and COL2 expression of cultured chondrocytes in the medium containing DC-ECM nanoparticles were up-regulated in comparison to negative control, which was further confirmed by presence more frequent number of larger size lacunae in micromass spheroids. Our findings support the use of ECM nanoparticles as condition supplement in culture medium and injectable biomaterials, especially for cell-based therapies for cartilage regeneration. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A:2463-2471, 2018.


Assuntos
Cartilagem Articular/metabolismo , Condrogênese , Matriz Extracelular/metabolismo , Nanopartículas/química , Cartilagem Articular/ultraestrutura , Diferenciação Celular , Forma Celular , Células Cultivadas , Condrócitos/citologia , Humanos , Nanopartículas/ultraestrutura
5.
Adv Biomed Res ; 5: 35, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27099848

RESUMO

BACKGROUND: Multiple sclerosis may have profound emotional consequences. The relation between psychological and physical factors could lead patients toward unforeseen disease. This study focuses on multiple sclerosis (MS) disease duration on personality type A and B in relation to individuals' behaviors. MATERIALS AND METHODS: This descriptive-analytical study was conducted in Isfahan Alzahra hospital in 2013. Three hundred MS patients and 100 healthy individuals were determined. The distributed questionnaires related to MS patients and considering the descriptive statistics such as demographic variables. Data were analyzed by SPSS software (version 18) based on Chi-square test and independent T-test. RESULTS: Disease duration varied between 1 to 38 years: 30% (1-4 years), 38% (5-10 years), 20% (10-20 years), and 12% (more than 20 years). Significant relationship was observed between disease duration and tendency to type A (higher stress). This relation was positive and significant in Relapsing Remitting MS patients; but negative correlation was seen in Secondary Progressive MS patients. These patients tended to type B (lower stress) when disease duration increased. CONCLUSIONS: Individuals with disease duration of one year and less than one year tend to type A personality, while patients with increment of disease duration have tendency to type B.

6.
J Res Med Sci ; 18(Suppl 1): S20-3, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23961278

RESUMO

BACKGROUND: Previous studies confirmed that neural gene expression in embryonic stem cells (ESC) could influence by chemical compounds through stimulating apoptotic pathway. We aimed to use ESCs-derived neural cells by embryoid body formation as an in vitro model for determination of neural gene expression changes in groups that treated by sera from Alzheimer's patients and compare with healthy individuals. MATERIALS AND METHODS: ESC line which was derived from the C57BL/6 mouse strain was used throughout this study. ESC-derived neural cells were treated with serum from Alzheimer's patient and healthy individual. Neural gene expression was assessed in both groups by quantitative real-time polymerase chain reaction analysis. The data was analyzed by SPSS Software (version 18). RESULTS: Morphologically, the reducing in neurite out-growth was observed in neural cells in group, which treated by serum from Alzheimer's patient, while neurite growth was natural in appearance in control group. Microtubule-associated protein 2 and glial fibrillary acidic protein expression significantly reduced in the Alzheimer's patient group compared with the control group. Nestin expression did not significantly differ among the groups. CONCLUSION: Neural gene expression could be reduced in serum treated ESC in Alzheimer's patients.

7.
Int J Prev Med ; 4(Suppl 2): S222-8, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23776728

RESUMO

BACKGROUND: Previous studies have shown that morphine consumption during pregnancy may cause delay or defect of embryo development or abnormal nervous system function in the human and animal models. In the present study, the highest density of morphine accumulation in the central nervous system of rat embryos was evaluated using C14-morphine. METHODS: Female Wistar rats (W 170-200 g) used and were crossed with male rats and coupling time was recorded (Embryonic day 0-E0). Experimental groups received 0.05 mg/ml of C14-morphine in drinking water daily. On the 10(th) and 17(th) days of pregnancy, pregnant rats were anesthetized and the embryos with these uterus and placenta were surgically removed and were fixed in formalin 10% for 4 week. Then the embryos were processed, sectioned in 25 µm and 5 µm thicknesses, fixed on the glasses for further evaluations. The sectioned in 25, the glasses were fixed on the Blanc black and white film for 6 h. Then, the films were appeared and their negatives were prepared. The sectioned in five staining hematoxylin and eosin by light microscope and MOTIC software. RESULTS: Our results indicated that the highest C14-morphine accumulation was observed in the vesicles and the ventricular choroid plexus (CP) of (E17) embryos, whereas, in the (E10) embryos. Highest concentration was observed in the brain vesicles and the ventricular CP. In addition, this study showed the surface area of lateral, 3(rd) and 4(th) ventricular CP in the experimental groups were increased in compared to control groups. CONCLUSIONS: Our results indicated that effects of morphine on reduction of embryos brain development may be due to the highest accumulation of C14-morphine in the CP and brain vesicles.

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