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1.
Foods ; 12(21)2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37959093

RESUMO

Squid ink melanin can be efficiently extracted from the byproduct ink sac generated during squid processing. As a natural food colorant, it possesses inherent antioxidant properties and the capability to adsorb heavy metals. This study aims to investigate the solubility of water-soluble squid ink melanin (WSSM) obtained from the ink sac, as well as its stability under various conditions including temperature, pH, salt, sugar, potassium sorbate, metal ions, sodium benzoate, sodium sulfite (reducing agent), and hydrogen peroxide (oxidizing agent). Moreover, it explores the scavenging effects of WSSM on free radicals and cadmium ions. The findings suggest that WSSM's stability is insignificantly affected by high temperature, sucrose, and salt. However, acidity, sodium benzoate, potassium sorbate, sodium sulfite (Na2SO3), and hydrogen peroxide (H2O2) significantly influence its stability. Most metal ions do not impact the stability of WSSM, except for Fe2+, Fe3+, Al3+, and Cu2+, which result in the precipitation of WSSM. Additionally, WSSM exhibits remarkable antioxidant activity with IC50 values of 0.91, 0.56, and 0.52 mg/mL for scavenging superoxide anion radicals (O2-·), hydroxyl radicals (·OH), and DPPH radicals, respectively. It also demonstrates the ability to adsorb the heavy metal Cd2+, with the adsorption rate gradually increasing with a higher temperature and larger amounts of WSSM added. Infrared spectroscopy analysis reveals the weakening of characteristic peaks (-COOH and -OH) during the process of Cd2+ adsorption by WSSM, while SEM confirms surface roughening and structural damage after Cd2+ adsorption. This study provides valuable insights for the utilization of squid melanin products as natural antioxidants and heavy metal adsorbents in the food industry.

2.
Environ Sci Technol ; 56(5): 2897-2916, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-35188384

RESUMO

Methoxyphenols emitted from lignin pyrolysis are widely used as potential tracers for biomass burning, especially for wood burning. In the past ten years, their atmospheric reactivity has attracted increasing attention from the academic community. Thus, this work provides an extensive review of the atmospheric reactivity of methoxyphenols, including their gas-phase, particle-phase, and aqueous-phase reactions, as well as secondary organic aerosol (SOA) formation. Emphasis was placed on kinetics, mechanisms, and SOA formation. The reactions of methoxyphenols with OH and NO3 radicals were the predominant degradation pathways, which also had significant SOA formation potentials. The reaction mechanism of methoxyphenols with O3 is the cycloaddition of O3 to the benzene ring or unsaturated C═C bond, while H-abstraction and radical adduct formation are the main degradation channels of methoxyphenols by OH and NO3 radicals. Based on the published studies, knowledge gaps were pointed out. Future studies including experimental simulations and theoretical calculations of other representative kinds of methoxyphenols should be systematically carried out under complex pollution conditions. In addition, the ecotoxicity of their degradation products and their contribution to SOA formation from the atmospheric aging of biomass-burning plumes should be seriously assessed.


Assuntos
Madeira , Aerossóis/química , Biomassa , Cinética
3.
Chemosphere ; 241: 125088, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31629237

RESUMO

Coniferyl alcohol derived from lignin pyrolysis, is a potential tracer for wood burning emissions, but its atmospheric stability toward OH radicals is not well known. In this work, the degradation kinetics of coniferyl alcohol by OH radicals was studied using a flow reactor at different OH concentrations, temperatures, and relative humidity (RH). The results showed that coniferyl alcohol could be degraded effectively by OH radials, and the average second-order rate constant (k2) was (11.6 ±â€¯0.5) × 10-12 cm3 molecule-1 s-1 at the temperature and RH of 25 °C and 40%, respectively. Additionally, increasing temperature facilitated the degradation of coniferyl alcohol and the Arrhenius equation could be expressed as k2 = (1.7 ±â€¯0.3) × 10-9exp [-(1480.2 ±â€¯55.6)/T] at 40% RH. Meanwhile, increasing RH had a negative impact on the degradation of coniferyl alcohol. According to the k2 obtained under different conditions, the atmospheric lifetime of coniferyl alcohol was in the range of 13.5 ±â€¯0.4 h to 22.9 ±â€¯1.4 h. The results suggested that the atmosphere lifetime of coniferyl alcohol was predominantly controlled by OH radicals.


Assuntos
Radical Hidroxila/química , Fenóis/química , Poluentes Atmosféricos/química , Atmosfera , Umidade , Cinética , Temperatura
4.
Exp Ther Med ; 13(6): 3607-3612, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28588688

RESUMO

Keloids are benign tumors that originate from scar tissues, but they usually overgrow beyond the original wounds. In a three-month single-center clinical trial, 69 patients were randomly divided into three groups. Patients in group 1 were treated with intralesional injection of diprospan (2 mg betamethasone disodium phosphate and 5 mg betamethasone dipropionate in 1 ml) with one-month intervals for three months. Patients in groups 2 and 3 were injected with a combination of 0.5 ml 5-fluorouracil (5-FU; 25 mg/ml) and diprospan as above for three months also. Prior to each injection, the keloids of patients in group 3 were additionally irradiated by a 1,064-nm neodymium-yttrium-aluminum-garnet (Nd:YAG) laser with a single pulse at an energy density of 90-100 J/cm2 and a pulse width of 12 msec. Clinical responses were evaluated by patient self-assessment and overall assessment by an observer according to the clinical signs of erythema, pruritus and pliability. A total of sixty-two patients completed the tests of the present study. At 2 and 3 months, the patients in all treatment groups showed an acceptable improvement in nearly all measurements. At the end of the study, the erythema and toughness score was significantly reduced and itch reduction was significantly greater in the diprospan + 5-FU + Nd:YAG group when compared to those in the other groups (P<0.05 for all indexes). The acceptable responses (good to excellent improvements) reported by blinded observers were as follows: 12% in the diprospan group, 48% in the diprospan + 5-FU group and 69% in the diprospan + 5-FU + Nd:YAG group. All of the results indicated that the combination of diprospan + 5-FU + Nd:YAG was the most efficacious therapy for keloid scars.

5.
Biomed Res Int ; 2016: 3853754, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26998485

RESUMO

OBJECTIVE: We evaluated synergistic efficacy and safety of combined topical application of Botulinum Toxin Type A (BTX-A) with fractional CO2 laser for facial rejuvenation. METHODS: Twenty female subjects were included for this split-face comparative study. One side of each subject's cheek was treated with fractional CO2 plus saline solution, and the other side was treated with fractional CO2 laser plus topical application of BTX-A. Patients received one session of treatment and evaluations were done at baseline, one, four, and twelve weeks after treatment. The outcome assessments included subjective satisfaction scale; blinded clinical assessment; and the biophysical parameters of roughness, elasticity, skin hydration, transepidermal water loss (TEWL), and the erythema and melanin index. RESULTS: BTX-A combined with fractional CO2 laser sides showed higher physician's global assessment score, subject satisfaction score, roughness, skin hydration, and skin elasticity compared to that of fractional CO2 plus saline solution side at 12 weeks after treatment. TEWL and erythema and melanin index showed no significant differences between two sides at baseline, one, four, and twelve weeks after treatment. CONCLUSION: Topical application of BTX-A could enhance the rejuvenation effect of fractional CO2 laser.


Assuntos
Toxinas Botulínicas Tipo A/administração & dosagem , Técnicas Cosméticas , Face , Terapia com Luz de Baixa Intensidade/métodos , Pele/metabolismo , Administração Tópica , Adulto , Elasticidade/efeitos dos fármacos , Eritema/etiologia , Eritema/metabolismo , Feminino , Humanos , Melaninas/metabolismo , Pessoa de Meia-Idade , Projetos Piloto , Perda Insensível de Água/efeitos dos fármacos
6.
Food Funct ; 5(7): 1360-8, 2014 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-24760201

RESUMO

Conjugated linolenic acid (CLNA) is a mixture of positional and geometric isomers of octadecatrienoic acid (α-linolenic acid, cis9,cis12,cis15-18:3 n-3) found in plant seeds. Three 8,10,12-18:3 isomers and four 9,11,13-18:3 isomers have been reported to occur naturally. CLNA isomers such as punicic acid, α-eleostearic acid and jacaric acid have been attributed to exhibit several health benefits that are largely based on animal and in vitro studies. This review has summarized and updated the evidence regarding the metabolism and bioactivities of CLNA isomers, and comprehensively discussed the recent studies on the effects of anti-carcinogenic, lipid metabolism regulation, anti-inflammatory, anti-obese and antioxidant activities of CLNA isomers. The available results may provide a potential application for CLNA isomers from natural sources, especially edible plant seeds, as effective functional food ingredients and dietary supplements for the above mentioned disease management. Further research, especially human randomized clinical trials, is warranted to investigate the detailed physiological effects, bioactivity and molecular mechanism of CLNA.


Assuntos
Ácidos Linoleicos Conjugados/química , Ácidos Linoleicos Conjugados/farmacologia , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Fármacos Antiobesidade/química , Fármacos Antiobesidade/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Carcinogênese/efeitos dos fármacos , Suplementos Nutricionais , Modelos Animais de Doenças , Humanos , Inflamação/tratamento farmacológico , Isomerismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Obesidade/tratamento farmacológico , Ensaios Clínicos Controlados Aleatórios como Assunto
7.
Exp Ther Med ; 6(4): 1022-1028, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24137309

RESUMO

The aim of this study was to investigate the photoprotective and immunoregulatory capacities of ginsenoside Rg1 in skin irradiated by chronic ultraviolet B (UVB) and to verify the potential mechanisms of action. BALB/c mice were pretreated with a topical application of ginsenoside Rg1 and irradiated with different doses of UVB daily for 30 consecutive days. Following chronic UVB irradiation, there were significant pathological changes in the skin of the BALB/c mice, including hyperkeratosis, acanthosis, sponge-like edematization and sunburn occurring in the epidermis, while edema, telangiectasis and inflammatory cell infiltration were observed in the papillary layer of the dermis. Treatment with ginsenoside Rg1 was able to reduce such changes induced by UVB irradiation. The number of p53 protein-positive stained cells following UVB irradiation was also observed by immunohistochemical analysis. Ginsenoside Rg1 downregulated the p53 protein expression induced by UVB irradiation, leading to reductions of 69.50, 23.53 and 12.93% at doses of 30, 60 and 120 mJ/cm2, respectively. Using reverse transcription polymerase chain reaction (RT-PCR), reductions in the levels of interferon (IFN)-γ mRNA expression were detected following UVB exposure; reductions of 19.6, 36.3 and 39.6% were observed following UVB irradiation at doses of 30, 60 and 120 mJ/cm2, respectively. The interleukin (IL)-10 mRNA expression levels increased by 40.1, 71.0 and 89.4% and the tumor necrosis factor (TNF)-α mRNA expression levels increased by 36.4, 18.4 and 8.6% following UVB irradiation at doses of 30, 60 and 120 mJ/cm2, respectively. However, pretreatment with ginsenoside Rg1 was observed to markedly attenuate the UVB irradiation-induced effects on the mRNA expression levels of the three cytokines. The topical application of ginsenoside Rg1 was able to protect the irradiated skin from UVB injury and reduce UVB-induced p53 protein expression. Ginsenoside Rg1 also demonstrated a potential regulatory effect on the UVB-induced local expression of the mRNA of the cytokines IFN-γ, IL-10 and TNF-α, which may be important in its immunoregulatory and inflammatory mechanisms.

8.
Arch Dermatol Res ; 300(6): 331-4, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18401588

RESUMO

Exposure to ultraviolet B (UVB) irradiation is a major risk factor for the development of skin cancer. Therefore, it is important to identify agents that can offer protection against UVB-caused DNA damage. Photocarcinogenesis is caused largely by mutations at the sites of incorrectly repaired DNA photoproducts, of which the most common are the cyclobutane pyrimidine dimers (CPDs). In this study, a DNA damage model of UVB irradiation-induced fibroblasts was established. The immunocytochemical staining, immuno dot blotting and Western blotting were employed in the study. We demonstrated that pre-treatment of fibroblasts with Baicalin dose-dependently reduced the amount of UVB-generated CPDs. Compared with UVB irradiated cells, UVB-induced p53 accumulation was less pronounced in Baicalin-treated cells. Taken together, these results suggest that Baicalin prevent CPDs formation induced by UVB. Baicalin is therefore a promising protective substance against UVB radiation.


Assuntos
Dano ao DNA/efeitos da radiação , Fibroblastos/efeitos da radiação , Flavonoides/farmacologia , Dímeros de Pirimidina/efeitos da radiação , Células Cultivadas , Pré-Escolar , Dano ao DNA/efeitos dos fármacos , Dano ao DNA/genética , Relação Dose-Resposta a Droga , Medicamentos de Ervas Chinesas/farmacologia , Exposição Ambiental/efeitos adversos , Fibroblastos/química , Fibroblastos/metabolismo , Humanos , Lactente , Recém-Nascido , Masculino , Dímeros de Pirimidina/química , Dímeros de Pirimidina/genética , Proteína Supressora de Tumor p53/antagonistas & inibidores , Proteína Supressora de Tumor p53/genética , Raios Ultravioleta/efeitos adversos
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