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1.
Water Sci Technol ; 84(1): 182-199, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34280163

RESUMO

In this study, polythiophene/Al2O3 (PTh/Al2O3) and polyaniline/Al2O3 (PAn/Al2O3) nanocomposites in the presence of poly(vinyl alcohol) (PVA) as the surfactant were synthesized via in situ chemical oxidative polymerization method in aqueous medium. The synthesized nanocomposites were characterized by scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD). Results indicated that the Al2O3 and poly(vinyl alcohol) influenced the properties of synthesized nanocomposites. The aim of this research was to investigate the sorption characteristics of polythiophene and polyaniline nanocomposites for the removal of heavy metal cations including Pb(II), Zn(II) and Cd(II) from aqueous solution. The factors that affected the adsorption equilibrium as well as the removal efficiency of the nanoadsorbents, i.e., contact time, metal ion concentration, pH and adsorption conditions were investigated in detail. From the kinetic results, it was concluded that the pseudo-second-order kinetic model was found to be the best at describing the adsorption process for Pb(II), Zn(II) and Cd(II) on PTh-PVA/Al2O3 and PAn-PVA/Al2O3. In addition, thermodynamic analysis suggests the endothermic and spontaneous nature of the present adsorption process with increased entropy on PTh-PVA/Al2O3 and PAn-PVA/Al2O3. The results suggest polythiophene, polyaniline and their nanocomposites have great potential to be used as efficient absorbent for the removal of heavy metal ions from water.


Assuntos
Metais Pesados , Nanocompostos , Poluentes Químicos da Água , Adsorção , Compostos de Anilina , Concentração de Íons de Hidrogênio , Íons , Cinética , Polímeros , Álcool de Polivinil , Termodinâmica , Tiofenos , Água , Poluentes Químicos da Água/análise
2.
Molecules ; 26(7)2021 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-33916814

RESUMO

The alkaline milieu of chronic wounds severely impairs the therapeutic effect of antibiotics, such as rifampicin; as such, the development of new drugs, or the smart delivery of existing drugs, is required. Herein, two innovative polyelectrolyte nanoparticles (PENs), composed of an amphiphilic chitosan core and a polycationic shell, were synthesized at alkaline pH, and in vitro performances were assessed by 1H NMR, elemental analysis, FT-IR, XRD, DSC, DLS, SEM, TEM, UV/Vis spectrophotometry, and HPLC. According to the results, the nanostructures exhibited different morphologies but similar physicochemical properties and release profiles. It was also hypothesized that the simultaneous use of the nanosystem and an antioxidant could be therapeutically beneficial. Therefore, the simultaneous effects of ascorbic acid and PENs were evaluated on the release profile and degradation of rifampicin, in which the results confirmed their synergistic protective effect at pH 8.5, as opposed to pH 7.4. Overall, this study highlighted the benefits of nanoparticulate development in the presence of antioxidants, at alkaline pH, as an efficient approach for decreasing rifampicin degradation.


Assuntos
Sistemas de Liberação de Medicamentos , Nanopartículas/química , Rifampina/farmacologia , Varredura Diferencial de Calorimetria , Cromatografia Líquida de Alta Pressão , Sulfato de Dextrana/química , Liberação Controlada de Fármacos , Concentração de Íons de Hidrogênio , Nanopartículas/ultraestrutura , Tamanho da Partícula , Polieletrólitos/química , Espectroscopia de Prótons por Ressonância Magnética , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Difração de Raios X
3.
J Clin Med ; 9(12)2020 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-33353110

RESUMO

The selection of a highly-viable single embryo in assisted reproductive technology requires an acceptable predictive method in order to reduce the multiple pregnancy rate and increase the success rate. In this study, the metabolomic profiling of growing and impaired embryos was assessed on the fifth day of fertilization using capillary electrophoresis in order to find a relationship between the profiling and embryo development, and then to provide a mechanistic insight into the appearance/depletion of the metabolites. This unique qualitative technique exhibited the appearance of most non-essential amino acids and lactate, and depleting the serine, alanyl-glutamine and pyruvate in such a manner that the embryos impaired in their development secreted a considerably higher level of lactate and consumed a significantly higher amount of alanyl-glutamine. The different significant ratios of metabolomic depletion/appearance between the embryos confirm their potential for the improvement of the prospective selection of the developed single embryos, and also suggest the fact that pyruvate and alanyl-glutamine are the most critical ATP suppliers on the fifth day of blastocyst development.

4.
Int J Biol Macromol ; 154: 18-24, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32147344

RESUMO

Designing novel biomaterials for tissue engineering purpose is an obvious necessary considering ever increasing need for appropriate biocompatibility and properties to achieve the maximum regeneration. In this research, a new type of biomaterial based on poly (phenylene sulfide) (PPS) and reduced graphene oxide (rGO) was synthesized and applied within chitosan based hydrogel to evaluate its performance as a wound dressing potentially. Fourier transform infrared spectroscopy (FTIR), X-ray diffraction spectrometry (XRD), scanning electron microscopy (SEM) and compression tests were performed to assess suitability of composite biomaterial. Thermal behavior of the PPS/rGO composite was evaluated by differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA). The PPS/rGO composition of 90: 10 (w/w) was selected because of having the highest biocompatibility and utilized in chitosan hydrogel. Chitosan hydrogel swelling ratio was declined from 800 to 200% by PPS/rGO addition; likewise, water vapor transition rate (WVTR) was dropped. A proper biocompatibility and cell attachment was confirmed, where porosity of ca. 80% appeared promising for tissue engineering uses. Overall, the result confirmed the appropriateness of PPS/rGO for tissue engineering uses.


Assuntos
Quitosana/química , Grafite/química , Polímeros/química , Engenharia Tecidual , Adesão Celular/efeitos dos fármacos , Eletroquímica , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Teste de Materiais , Polímeros/farmacologia , Alicerces Teciduais/química
5.
J Food Sci Technol ; 54(13): 4277-4283, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29184234

RESUMO

In this study, the effect of gamma irradiation on the shelf life and properties of cucumber was investigated. These properties include weight reduction, fruit density, juice, tissue firmness, total soluble solids (TSS), total titratable acidity, chlorophyll and vitamin C, pH, marketability, flavor, frostbite and fungal effects. For this purpose, cucumbers were irradiated with dose of 2, 2.5 and 3 kGy. The exposure time was calculated by MCNP4C; the Monte Carlo particle transport code. Three types of fungi (white-Sclerotinia sclerotiorum, gray-Botrytis cinerea and olive-Cladosporium cucumerinum), were used to infect some samples. The chlorophyll and vitamin C preservation abilities were increased to about 3 and 1.4 times, respectively with irradiation treatment. Also, the shelf life was increased about 1 week, while chilling injuries is decreased. Samples' resistance to the fungal growth was evident and the process of fungal growth on the irradiated samples was delayed up to 1 week. The best properties were obtained at the irradiation dose of 2 kGy since it had less effect on flavor, TSS and tissue firmness.

6.
Int J Hematol Oncol Stem Cell Res ; 8(3): 24-9, 2014 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-25642305

RESUMO

INTRODUCTION: Acute Myeloid Leukemia is a malignant transformation of hematopoietic tissue, bone marrow infiltration of undifferentiated cells known as blasts that interfere with the production of normal cells. Vascular endothelial growth factor (VEGF) is persistently secreted from myeloid cells and high levels can be detected in patients' serum. METHODS: Twenty-one AML patients, who were chemotherapy candidates were evaluated in a clinical trial. Serum VEGF was measured by ELISA. VEGFA, VEGFC mRNA and bone marrow MVD were measured in all patients before and after chemotherapy and then all results were analyzed. RESULTS: There were 10 (48%) female and 11(52%) male patients ranged in age from 20 to 60 years, with an average age of 39.5 ±14.1 years. The mean amount of MVD was reduced from 10.8±3.6 before chemotherapy to7.6±3.3 after chemotherapy (P=0.008). VEGF was also reduced from 0.59±0.16 before chemotherapy to 0.24±0.03 after chemotherapy (P=0.005). Gene expression differences for VEGFA mRNA was 4.6±1.4, while it was 120.7±93.2 for VEGFC mRNA, showing the significance only for VEGA mRNA (P=0.02). CONCLUSION: Regarding reduced angiogenesis, we can conclude that anti-angiogenic preparations can be effective in treatment course of AML in combination with chemotherapy regimen.

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