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1.
J Oleo Sci ; 69(1): 73-82, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31902898

RESUMO

The physicochemical and sunscreen properties of marl as a function of particle size were investigated. The research findings established that the marl under investigation consisted of more than 95% calcium carbonate (CaCO3). The particles of marl inspected under a scanning electron microscope were calcite, which is the stable polymorph of CaCO3, with a rhombohedral structure. The particle size classification by the sieving method showed that grinding using a ball mill could downsize the marl particles by 2 to 3 times, reaching below 15 µm on average. Marl particles showed a tendency to reflect ultraviolet A (UVA) rays rather than UVB rays and a possibility to steadily absorb both UVAII and UVAI. Finer particles obtained after a longer grinding process demonstrated higher efficacy regarding UV reflection and absorption properties. The 3 wt.% marl displayed a sun protection factor (SPF) value of 1 to 2. However, marl demonstrated a good ability to protect against radiation over a broad spectrum range with a critical wavelength above 370 nm. The addition of marl in the formulation containing avobenzone and octinoxate had a positive synergistic effect because the marl was able to increase the UV absorbance efficacy (based on the area under the curve (AUC) value) and SPF value of the cream. Furthermore, it was also discovered that the added marl powder could slow the decrease in UV protection efficacy of the products in terms of the AUC calculated from the absorbance profile after exposure to simulated UV rays with an amplitude range of 10 J/cm2 to 40 J/cm2 for 30 min, which was similar to the results obtained from octocrylene and bemotrizinol.


Assuntos
Fenômenos Químicos , Protetores Solares/química , Carbonato de Cálcio/química , Tamanho da Partícula
2.
J Oleo Sci ; 66(12): 1311-1319, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29199206

RESUMO

Nanostructured lipid carriers loaded salicylic acid (NLCs-SA) were developed and optimized by using the design of experiment (DOE). Box-Behnken experimental design of 3-factor, 3-level was applied for optimization of nanostructured lipid carriers prepared by emulsification method. The independent variables were total lipid concentration (X1), stearic acid to Lexol® GT-865 ratio (X2) and Tween® 80 concentration (X3) while the particle size was a dependent variable (Y). Box-Behnken design could create 15 runs by setting response optimizer as minimum particle size. The optimized formulation consists of 10% of total lipid, a mixture of stearic acid and capric/caprylic triglyceride at a 4:1 ratio, and 25% of Tween® 80 which the formulation was applied in order to prepare in both loaded and unloaded salicylic acid. After preparation for 24 hours, the particle size of loaded and unloaded salicylic acid was 189.62±1.82 nm and 369.00±3.37 nm, respectively. Response surface analysis revealed that the amount of total lipid is a main factor which could affect the particle size of lipid carriers. In addition, the stability studies showed a significant change in particle size by time. Compared to unloaded nanoparticles, the addition of salicylic acid into the particles resulted in physically stable dispersion. After 30 days, sedimentation of unloaded lipid carriers was clearly observed. Absolute values of zeta potential of both systems were in the range of 3 to 18 mV since non-ionic surfactant, Tween® 80, providing steric barrier was used. Differential thermograms indicated a shift of endothermic peak from 55°C for α-crystal form in freshly prepared samples to 60°C for ß´-crystal form in storage samples. It was found that the presence of capric/caprylic triglyceride oil could enhance encapsulation efficiency up to 80% and facilitate stability of the particles.


Assuntos
Fenômenos Químicos , Portadores de Fármacos/química , Desenho de Fármacos , Nanoestruturas , Ácido Salicílico/química , Cristalização , Estabilidade de Medicamentos , Tamanho da Partícula , Polissorbatos , Ácidos Esteáricos , Temperatura , Triglicerídeos
3.
J Altern Complement Med ; 22(8): 669-75, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27391857

RESUMO

BACKGROUND: A recent study showed that Gynura pseudochina DC. var. hispida Thv. leaf extract (GP) can reduce the activation of the nuclear factor κB (NF-κB) pathway and suppress the release of interleukin (IL)-1ß, IL-6, and tumor necrosis factor -α, which play an important role in the pathogenesis of psoriasis. METHODS: Twenty-five patients with mild to moderate plaque psoriasis completed a 4-week trial. Twice daily, they applied the GP ointment on psoriatic lesions on one side of the body, and they applied 0.1% triamcinolone (TA) cream on the other side. The Targeted Area Score (TAS), Psoriasis Severity Index (PSI) scores, and Physician's Global Assessment (PGA) scores were assessed at baseline and at weeks 1, 2, 3, and 4. Pre- and post-treatment skin samples were taken. Phosphorylation of NF-κB p65, Ki-67, and epidermal thickness were analyzed through immunohistochemistry. RESULTS: The TAS for erythema, scaling, and induration and PSI scores decreased on both treated sides. A statistically significant difference was observed beginning at the first week of treatment. The GP ointment significantly decreased scaling scores. However, no significant differences were observed between the TAS for erythema and induration or the PSI and PGA scores. Immunohistochemical staining revealed diminution of phosphorylated NF-κB p65, Ki-67, and epidermal thickness in the lesions treated with the GP ointment. The ointment was well tolerated, with minimal side effects. No laboratory abnormalities were detected. CONCLUSIONS: The GP ointment demonstrated efficacy similar to that of 0.1% TA cream for mild to moderate chronic plaque psoriasis. In addition, its short-term side effects were minimal.


Assuntos
Anti-Inflamatórios/uso terapêutico , Asteraceae/química , Extratos Vegetais/uso terapêutico , Psoríase/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Anti-Inflamatórios/efeitos adversos , Anti-Inflamatórios/química , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Extratos Vegetais/efeitos adversos , Extratos Vegetais/química , Adulto Jovem
4.
J Oleo Sci ; 63(6): 645-52, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24829133

RESUMO

Lycopene, a lipophilic carotenoid, has been known as an effective antioxidant in supporting the cutaneous defensive system. However, it is unstable when exposed to light and water. In this study, lycopene was isolated from tomatoes and a vesicular delivery system was developed to entrap and stabilize the lycopene in the aqueous system. A simple process, maceration in ethyl acetate, was used to extract lycopene from the tomatoes. The extract was then chromatographed on the Sephadex LH20 column using acetone as a solvent system to yield 995 µg of lycopene per gram of dried tomato weight. The vesicular delivery system was prepared from a combination of ascorbic acid-6-palmitate (AP), cholesterol and dicetyl phosphate using a thin film hydration method. The formulation was composed of AP, cholesterol and dicetyl phosphate at a 44:44:12 molar ratio and with 2.12 µmol/ml of the isolated lycopene. Both blank vesicles and lycopene loaded vesicles were kept for a period of 3 months at 4±2°C and at the room temperature (28±2°C) to evaluate the effect of the encapsulation on the characteristic of the vesicles and on the antioxidant activity of the encapsulated lycopene. The result implied that lycopene could be stabilized in the vesicles and its scavenging activity against DPPH free radicals was superior to that of the free lycopene solution.


Assuntos
Carotenoides/isolamento & purificação , Carotenoides/farmacologia , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Ácido Ascórbico/análogos & derivados , Colesterol , Cromatografia Líquida de Alta Pressão , Sistemas de Liberação de Medicamentos , Estabilidade de Medicamentos , Sequestradores de Radicais Livres , Licopeno , Solanum lycopersicum/química , Organofosfatos , Temperatura , Fatores de Tempo , Água
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