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1.
Biomed Chromatogr ; : e5993, 2024 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-39152776

RESUMO

Colorectal cancer (CRC) is the fourth most common cause of malignant tumor death. The development of novel, more effective drugs is desperately needed to treat CRC. Zingiber officinale is believed to possess anticancer properties due to its flavonoids and phenols. Using Soxhlet (SOXT) and maceration (MACR) techniques, the present study aimed to evaluate the amounts of quercetin, gallic acid, rutin, naringin, and caffeic acid in ginger capsules of Z. officinale. High-performance liquid chromatography (HPLC)/ultraviolet was used for separation and quantitation. In vitro toxicity evaluation of ginger capsules on the CRC cell line HT-29 was also conducted to assess the anticancer activity of the supplement. The cell line HT-29 (HTB-38) colorectal adenocarcinoma was utilized for the antiproliferative effect of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide. Ginger herbal supplement extract at dosages of 200 and 100 µg had strong cytotoxic effects (IC50 < 50 µg/mL) on HT-29 CRC cells via MACR. This extract is comparable to the SOXT extract, which has an IC50 of less than 50 µg/mL. The anticancer effect of ginger herbal supplement formulations against CRC lines was investigated, and the results obtained from both the MACR and SOXT extraction procedures were noteworthy. The quercetin content was the highest of all the extracts according to the HPLC data.

2.
Biomed Chromatogr ; 37(11): e5716, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37580869

RESUMO

Chronic wounds have become a major concern for healthcare systems, as they have been related to diabetic foot ulcers, venous leg ulcers and pressure ulcers. Oleuropein is an active compound that is extracted from olive leaves and it has the ability to reduce injury to tissues owing to its antioxidant effect, hence improving wound healing. The poor pharmacokinetics of oleuropein have limited its use clinically. This work is aimed toward studying the impact of PEGylated and non-PEGylated nanoliposomes loaded with oleuropein, as a carrier model, on wound-healing activity. The thin film hydration method was used to compose PEGylated and non-PEGylated liposomes, both loaded with oleuropein. The results indicated that each free, PEGylated and non-PEGylated composition was within the limit of optimum nanoliposome characterization. The results showed that non-PEGylated compositions produced higher efficiency in encapsulation (47.09 ± 10.06%) than the PEGylated ones (20.97 ± 10.52%). The PEG-nanoliposomes loaded with oleuropein (PEG-oleu) had mean size, charge and polydispersity index of 129.35 nm, -9.55 mV and 0.1010, respectively. The scratch assay results proved that PEGylated liposomal compositions have a more rapid wound-healing activity than non-PEGylated ones at different time intervals at 0, 2, 24 and 28 h.


Assuntos
Glucosídeos Iridoides , Lipossomos , Cicatrização , Polietilenoglicóis
3.
ScientificWorldJournal ; 2014: 942978, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24955426

RESUMO

The physical and mechanical properties of mortar containing synthetic cosurfactants as air entraining agent are investigated. The cosurfactants consist of a combination of 2% dodecyl benzene sodium sulfonate (DBSS) and either 1.5% polyvinyl alcohol (PVA) or 1.5% polyoxyethylene glycol monomethyl ether (POE). Also these cosurfactants were used to prepare copolymers latex: styrene/butyl methacrylate (St/BuMA), styrene/methyl methacrylate (St/MMA), and styrene/glycidyl methacrylate (St/GMA), in order to study their effects on the properties of mortar. The properties of mortar examined included flow table, W/C ratio, setting time, water absorption, compressive strength, and combined water. The results indicate that the latex causes improvement in mortar properties compared with cosurfactants. Also polymer latex containing DBSS/POE is more effective than that containing DBSS/PVA.


Assuntos
Metacrilatos/química , Estireno/química , Tensoativos/química , Força Compressiva , Compostos de Epóxi/química , Teste de Materiais , Polímeros/química
4.
ScientificWorldJournal ; 2014: 670710, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25254256

RESUMO

This paper investigates the physicomechanical properties of mortar containing high volume of fly ash (FA) as partial replacement of cement in presence of copolymer latexes. Portland cement (PC) was partially replaced with 0, 10, 20, 30 50, and 60% FA. Copolymer latexes were used based on 2-hydroxyethyl acrylate (2-HEA) and 2-hydroxymethylacrylate (2-HEMA). Testing included workability, setting time, absorption, chemically combined water content, compressive strength, and scanning electron microscopy (SEM). The addition of FA to mortar as replacement of PC affected the physicomechanical properties of mortar. As the content of FA in the concrete increased, the setting times (initial and final) were elongated. The results obtained at 28 days of curing indicate that the maximum properties of mortar occur at around 30% FA. Beyond 30% FA the properties of mortar reduce and at 60% FA the properties of mortar are lower than those of the reference mortar without FA. However, the addition of polymer latexes into mortar containing FA improved most of the physicomechanical properties of mortar at all curing times. Compressive strength, combined water, and workability of mortar containing FA premixed with latexes are higher than those of mortar containing FA without latexes.


Assuntos
Adesivos/química , Cinza de Carvão/química , Materiais de Construção , Látex/química , Acrilatos/química , Força Compressiva , Teste de Materiais/métodos , Fenômenos Mecânicos , Metacrilatos/química , Microscopia Eletrônica de Varredura , Fenômenos Físicos , Água/química
5.
Heliyon ; 10(3): e24966, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38327448

RESUMO

This article discusses the main technologies for processing titanium-containing raw materials, the advantages, and disadvantages of various technological solutions. The analysis of the literature revealed that the traditional methods for the production of titanium products are mainly focused on the use of ilmenite concentrates. In connection with the depletion of ilmenite deposits, in the near future, there will inevitably be a need for a switch to the use of complex ores - titanomagnetite. Obtaining titanium dioxide (TiO2) from titanomagnetite raw materials with a high content of impurity components requires an individual approach for each specific deposit. The possibility of further improving the development of a technological process for low-temperature (1000-1200 °C) processing of titanomagnetite concentrates via the production of pure TiO2 is proposed.

6.
Heliyon ; 10(12): e33282, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-39022089

RESUMO

The effect of different contents of fullerene on the properties of polyurethane resins (PUs), including rheology and thermal properties, was investigated. Polyurethane resins were prepared through polyaddition reactions using different isocyanate monomers such as isophorone diisocyanate (IPDI), methylene diphenyl diisocyanate (MDI), hexamethylene diisocyanate (HDI), and different polyols, such as poly(oxytetramethylene) glycol (PTMG), the triol trade name FA-703, and polypropylene glycols (PPG), at an NCO/OH ratio 0.94 and a temperature of 100 °C. IR spectroscopy was used to control the polymerization of PUs through the shifting of NCO peaks. The results showed that the rheology and thermal properties of the prepared PU resins depend on the type of isocyanates and fullerene used. Based on the type of isocyanates, the PU resin prepared by MDI has the highest viscosity and thermal stability compared to the other isocyanates investigated. On the other hand, the PU resins prepared by IPDI mixed with fullerene had the highest viscosity and thermal stability. However, the initial decomposition temperature (T onset) of the PUs decreased with the addition of fullerene without affecting the maximum decomposition temperature (PDT max) of the PU resin.

7.
Polymers (Basel) ; 15(15)2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37571059

RESUMO

Blend copolymers (PVA/S) were grafted with polyethylene glycol methyl methacrylate (PEGMA) with different ratios. Potassium persulfate was used as an initiator. The blend copolymer (PVA/S) was created by combining poly(vinyl alcohol) (PVA) with starch (S) in various ratios. The main idea was to study the effect of different ratios of the used raw materials on the biodegradability of plastic films. The resulting polymers (PVA/S/PEGMA) were analyzed using FTIR spectroscopy to investigate the hydrogen bond interaction between PVA, S, and PEGMA in the mixtures. TGA and SEM analyses were used to characterize the polymers (PVA/S/AA). The biodegradability and mechanical properties of the PVA/S/PEGMA blend films were evaluated. The findings revealed that the mechanical properties of the blend films are highly influenced by PEGMA. The time of degradation of the films immersed in soil and Coca-Cola increases as the contents of PVA and S and the molecular weight (MW) of PEGMA increase in the terpolymer. The M8 sample (PVA/S/PEGMA in the ratio of 3:1:2, respectively) with a MW of 950 g/mol produced the lowest elongation at break (67.5%), whereas M1 (PVA/S/PEGMA in the ratio of 1:1:1, respectively) with a MW of 300 g/mol produced the most (150%). The film's tensile strength and elongation at break were improved by grafting PEGMA onto the blending polymer (PAV-b-S). Tg and Tm increased when the PEGMA MW increased from 300 to 950. Tg (48.4 °C) and Tm (190.9 °C) were the lowest in M1 (300), while Tg (84.8 °C) and Tm (190.9 °C) were greatest in M1 (950) at 209.3 °C. The increased chain and molecular weight of PEGMA account for the increase in Tg and Tm of the copolymers.

8.
ADMET DMPK ; 11(4): 533-550, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37937243

RESUMO

Background and Purpose: Apixaban (AP) is a factor X inhibitor, an orally active drug that inhibits blood coagulation for better prevention of venous thromboembolism. It has poor solubility, dissolution rate and low bioavailability. The aim of this study was to improve the aqueous solubility and dissolution rate of oral AP as a step to enhance its bioavailability by preparing it as an inclusion complex with beta- and hydroxy propyl beta-cyclodextrin. Experimental Approach: A simple, rapid method of analysis of AP was developed using ultraviolet spectrophotometry (UV) and partially validated in terms of linearity, precision and accuracy, recovery, and robustness. AP was prepared as a complex with beta cyclodextrin (ßCD) and hydroxy propyl beta cyclodextrin (HPßCD) in weight ratios 1:1, 1:2, and 1:3 by kneading, solvent evaporation and spray drying methods and characterized by Fourier transfer infra-red (FTIR), differential scanning calorimetry (DSC), and percent drug content in each of the prepared complex. Using the computer simulation, the interactions of AP with ßCD and HPßCD were investigated. Key Results: The phase solubility study showed that the solubility of AP was greatly enhanced from 54×10-3 mmol /L to 66 mmol/L using HPßCD with acceptable stability constant. Computer docking supports the formation of a stable 1:1 complex between AP and CD's. The dissolution test results showed that the complex gave a significantly higher percentage of drug release (95%) over one hour compared to the free AP (60%) (p<0.05). Conclusion: AP- HPßCD complex in the ratio of 1:2 (w/w) can significantly improve the solubility and in vitro dissolution rate of AP.

9.
Materials (Basel) ; 14(20)2021 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-34683781

RESUMO

Hydrogel copolymers based on N,N-dimethyl acrylamide (DMA) and acrylic acid (AAc) were synthesized using a solution polymerization technique with different monomer ratios and ammonium persulfate as an initiator. This paper investigates the thermal stability, physical and chemical properties of the hydrogel copolymer. Testing includes Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), scanning electron microscopy (SEM) and elemental analysis (CHNS). The copolymer composition was determined by elemental analysis, and the reactivity ratios of monomers were calculated through linearization methods such as Fineman-Ross (FR), inverted Fineman-Ross (IFR), Kelen-Tudos (KT) and Mayo-Lewis (ML). Good agreement was observed between the results of all four methods. The ratio of r1 and r2 were 0.38 (r1) and 1.45 (r2) (FR), 0.38 (r1) and 1.46 (r2) (IFR), 0.38 (r1) and 1.43 (r2) (KT), and 0.38 (r1) and 1.45 (r2) (ML). Hydrogel copolymers exhibited good thermal stability, and SEM showed three-dimensional porous structures. Antibiotic-free and antibiotic-loaded hydrogels demonstrated antimicrobial properties against both Gram-positive and Gram-negative bacteria. As the ratio of DMA in hydrogel copolymer increased, the activity of copolymer against bacteria enhanced. The results indicated that these hydrogels have the potential to be used as antibacterial materials.

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