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1.
Anal Chem ; 93(3): 1732-1739, 2021 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-33355452

RESUMO

Rare earth elements (REEs) are used widely in devices of many fields, but it is still a troublesome task to achieve their selective separation and purification. Metal-organic frameworks (MOFs) as an emerging porous crystalline material have been used for selective separation of REEs using the size-selective crystallization properties. However, so far, almost all MOFs cannot be used directly for selective separation of REEs in strong acid via solid-state adsorption. Herein, a zinc-trimesic acid (Zn-BTC) MOF is grown by solid synthesis in situ on ZnO nanoparticles covering nanoporous graphene for preparing Zn-BTC MOF/nanoporous graphene composites with strong acid resistance. The adsorption capacity of the resulting composites to REEs is highly sensitive to the ionic radius, which may be attributed to the fact that the REE ions coordinate with O to form a stable structure. The selectivity of Ce/Lu is ≈10,000, and it is extremely important that the selectivity between adjacent REEs (e.g., Nd/Pr) is as high as ≈9.8, so the composite exhibits the best separation performance so far. This work provides a green, facile, scale, and effective synthesis strategy of Zn-BTC MOF/nanoporous graphene, which is hopefully applied directly in the separation industries of REEs.

2.
Exp Eye Res ; 203: 108399, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33352197

RESUMO

Alkali burn to the cornea is one of the most intractable injuries to the eye due to the opacity resulting from neovascularization (NV) and fibrosis. Numerous studies have focused on studying the effect of drugs on alkali-induced corneal injury in mouse, but fewer on the involvement of alkali-induced DNA methylation and the PI3K/AKT/mTOR signaling pathway in the mechanism of alkali-induced corneal injury. Thus, the aim of this study was to determine the involvement of DNA methyltransferase 3 B-madiated DNA methylation and PI3K/AKT/mTOR signaling modulation in the mechanism of alkali-induced corneal injury in a mouse model. To this end, we used bisulfite sequencing polymerase chain reaction and Western blot analysis, to study the effects of 5-aza-2'-deoxycytidine and 2-(4-morpholinyl)-8-phenyl-4H-1-benzopyran-4-one, which inhibit methyltransferase and PI3K respectively, on DNA methylation and expression of downstream effectors of PI3K related to corneal NV, including TSC1 and mTOR genes. The results showed that, after an intraperitoneal injection of rapamycin (2 mg/kg/day) for seven days, the alkali-induced opacity and NV were remarkably decreased mainly by suppressing the infiltration of immune cells into injured corneas, angiogenesis, VEGF expression and myofibroblasts differentiation; as well as by promoting corneal cell proliferation and PI3K/AKT/mTOR signaling. More significantly, these findings showed that epigenetic regulatory mechanisms by DNA methylation played a key role in corneal NV, including in corneal alkali burn-induced methylation modification and rapamycin-induced DNA demethylation which involved the regulation of the PI3K/AKT/mTOR signaling pathway at the protein level. The precise findings of morphological improvement and regulatory mechanisms are helpful to guide the use of rapamycin in the treatment of corneal angiogenesis induced by alkaline-burn.


Assuntos
Queimaduras Químicas/prevenção & controle , Lesões da Córnea/prevenção & controle , Queimaduras Oculares/induzido quimicamente , Imunossupressores/uso terapêutico , Sirolimo/uso terapêutico , Serina-Treonina Quinases TOR/genética , Proteína 1 do Complexo Esclerose Tuberosa/genética , Actinas/genética , Animais , Western Blotting , Queimaduras Químicas/genética , Queimaduras Químicas/patologia , Cromonas/farmacologia , Lesões da Córnea/genética , Lesões da Córnea/patologia , Metilação de DNA , Modelos Animais de Doenças , Técnica Indireta de Fluorescência para Anticorpo , Regulação da Expressão Gênica/fisiologia , Masculino , Camundongos , Morfolinas/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase/farmacologia , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Hidróxido de Sódio/toxicidade , Fator A de Crescimento do Endotélio Vascular/genética
3.
Exp Eye Res ; 210: 108700, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34245755

RESUMO

Age-related macular degeneration (AMD) is a complex retinal disease with no viable treatment strategy. The causative mechanistic pathway for this disease is not yet clear. Therefore, it is highly warranted to screen effective drugs to treat AMD. Rapamycin are known to inhibit inflammation and has been widely used in the clinic as an immunosuppressant. This study aimed to investigate the protective effect of rapamycin on the AMD retinal degeneration model. The AMD models were established by injection of 35 mg/kg sodium iodate (NaIO3) into the tail vein. Then the treated mice intraperitoneally received rapamycin (2 mg/kg) once a day. The histomorphological analysis showed that rapamycin could inhibit retinal structure damage and apoptosis. Experiments revealed that rapamycin significantly attenuated inflammatory response and oxidative stress. Our experimental results demonstrated that rapamycin has protected the retinal against degeneration induced by NaIO3. The therapeutic effect was more significant after 7 days of treatment. Therefore, our study potentially provides a powerful experimental support for the treatment of AMD.


Assuntos
Modelos Animais de Doenças , Imunossupressores/uso terapêutico , Degeneração Retiniana/prevenção & controle , Epitélio Pigmentado da Retina/efeitos dos fármacos , Sirolimo/uso terapêutico , Animais , Apoptose/efeitos dos fármacos , Proteína Glial Fibrilar Ácida/metabolismo , Marcação In Situ das Extremidades Cortadas , Injeções Intraperitoneais , Iodatos/toxicidade , Masculino , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Retina/metabolismo , Retina/patologia , Degeneração Retiniana/induzido quimicamente , Degeneração Retiniana/metabolismo , Degeneração Retiniana/patologia , Epitélio Pigmentado da Retina/metabolismo , Epitélio Pigmentado da Retina/patologia , Rodopsina/metabolismo , cis-trans-Isomerases/metabolismo
4.
ACS Appl Bio Mater ; 7(2): 1064-1072, 2024 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-38286026

RESUMO

Virus-like particle (VLP) vaccine is considered to be the most promising candidate alternative to the traditional inactivated vaccine for foot-and-mouth disease (FMD). To elicit a desired immune response, hollow mesoporous silica nanoparticles (HMSNs) have been synthesized and utilized as a nanocarrier for FMD VLP vaccine delivery. The as-prepared HMSNs displayed a relatively small particle size (∼260 nm), large cavity (∼150 nm), and thin wall (∼55 nm). The inherent structural superiorities make them ideal nanocarriers for the FMD VLP vaccine, which exhibited good biocompatibility, great protein-loading capacity, high antibody-response level, and protective efficiency, even comparable to commercial adjuvant ISA 206. All the results suggested that HMSNs may be a valid nanocarrier in VLP-based vaccines.


Assuntos
Vírus da Febre Aftosa , Febre Aftosa , Nanopartículas , Vacinas , Animais , Dióxido de Silício/química , Febre Aftosa/prevenção & controle , Nanopartículas/química
5.
Nanoscale Adv ; 5(7): 1936-1942, 2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-36998661

RESUMO

The effectiveness of photocatalysts can be impacted by the high compounding efficiency of photogenerated carriers, which depends on the morphology of the photocatalyst. Here, a hydrangea-like N-ZnO/BiOI composite has been prepared for achieving efficient photocatalytic degradation of tetracycline hydrochloride (TCH) under visible light. The N-ZnO/BiOI exhibits a high photocatalytic performance, degrading nearly 90% of TCH within 160 min. After 3 cycling runs, the photodegradation efficiency remained above 80%, demonstrating its good recyclability and stability. The major active species at work are superoxide radicals (·O2 -) and photo-induced holes (h+) in the photocatalytic degradation of TCH. This work provides not only a new idea for the design of photodegradable materials but also a new method for the effective degradation of organic pollutants.

6.
Arq Bras Oftalmol ; 85(4): 389-398, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34586243

RESUMO

PURPOSE: To systematically examine the dynamic changes and time sequence in corneal epithelial cell apoptosis after excessive ultraviolet B irradiation. METHODS: Ultraviolet B (144 mJ/cm2) was used to irradiate rat corneal epithelial cells for 2 h. Cell morphology was observed on differential interference contrast microscopy, and the numbers of the different kinds of apoptotic cells were counted using the ImageJ software. Cell viability was measured with the 3-(4,5-dimethyl-2-thiazolyl)-2,5- diphenyl-2-H-tetrazolium bromide method. Cell apoptotic rate and loss of mitochondrial membrane potential were detected using flow cytometric analyses. The expression levels of 3 apoptotic genes were measured with real-time quantitative polymerase chain reaction at different time points within 0-24 h after irradiation. RESULTS: After 144-mJ/cm2 ultraviolet B irradiation for 2 h, the expression levels of caspase-8 and Bax were highest at 0 h; furthermore, the mitochondrial membrane potential decreased at 0 h and remained constant for 6 h in a subsequent culture. At 6 h, caspase-3 was activated. The decrease in cell viability and increase in apoptotic rate peaked at 6 h. The caspase-3 expression level decreased within 12-24 h, which led to a decline in apoptotic rate and change in apoptotic stage. CONCLUSIONS: The corneal epithelial cells exhibited rapid apoptosis after ultraviolet B irradiation, which was associated with both extrinsic and intrinsic pathways.


Assuntos
Apoptose , Córnea , Células Epiteliais , Animais , Apoptose/efeitos da radiação , Caspase 3 , Sobrevivência Celular/efeitos da radiação , Córnea/citologia , Células Epiteliais/citologia , Células Epiteliais/efeitos da radiação , Ratos , Raios Ultravioleta/efeitos adversos
7.
ACS Appl Bio Mater ; 4(5): 4522-4531, 2021 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-35006788

RESUMO

Adequate treatment of skin wounds is vital to health. Nitrocellulose bandage as a traditional wound dressing is widely used for wound healing, but its limited air permeability and poor sterilization need to be improved for enhancing the actual efficacy. Here, nanoporous graphene (NPG) is used to mix into nitrocellulose for preparing a composite membrane, which exhibits a moderate transmission rate of water vapor, excellent toughness performance, and good biocompatibility. Moreover, the membrane shows an excellent broad-spectrum antibacterial property (>98%, Escherichia coli; >90%, Staphylococcus aureus) and can reduce the risk of microbial infection for the body after trauma. Importantly, after using the nanoporous graphene/nitrocellulose membrane, the wound closure percentage reaches 93.03 ± 1.08% at 7 days after the trauma, and the degree of skin tissue recovery is also improved significantly. Therefore, this study develops a highly efficient wound healing dressing, which is expected to be used directly in clinics.


Assuntos
Antibacterianos/farmacologia , Materiais Biocompatíveis/farmacologia , Escherichia coli/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , Antibacterianos/síntese química , Antibacterianos/química , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/química , Linhagem Celular , Celulose/química , Celulose/farmacologia , Infecções por Escherichia coli/tratamento farmacológico , Grafite/química , Grafite/farmacologia , Humanos , Teste de Materiais , Testes de Sensibilidade Microbiana , Nitrocompostos/química , Nitrocompostos/farmacologia , Tamanho da Partícula , Porosidade , Pele/efeitos dos fármacos , Pele/patologia , Infecções Estafilocócicas/tratamento farmacológico , Propriedades de Superfície
8.
J Biosci Bioeng ; 104(5): 391-7, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18086439

RESUMO

The alga Isochrysis galbana 8701 and the yeast Ambrosiozyma cicatricosa were mix-cultivated in the same medium for 7 d to compare their growth performance and biochemical composition with those of the same organisms cultured under monoculture conditions. The specific growth rates of both species were significantly higher (p<0.05) in the mixed culture than in the monocultures during the corresponding experimental phases. At the end of experiment, the biomass concentration obtained in the mixed culture reached 1.32+/-0.04 g/l of dry weight, which was significantly higher (p<0.05) than those obtained in monocultures, and the alga I. galbana in the mixed culture dominated the cell numbers making up 96.64% of the cells. The biochemical profile of the mixed culture is similar to that of the I. galbana monoculture with some variations; The percentages of both the fatty acids 14:00 and 18:00 detected in the mixed culture were significantly higher (p<0.05) than those detected in the I. galbana monoculture, while the content of the fatty acid 18:2(n-6) detected in the mixed culture was significantly lower (p<0.05) than that detected in the I. galbana monoculture. This study indicates the improved growth performance in mixed culture compared with monocultures and the similarities between the biochemical compositions of the mixed culture and the I. galbana monoculture.


Assuntos
Eucariotos/química , Eucariotos/crescimento & desenvolvimento , Saccharomycetales/química , Saccharomycetales/crescimento & desenvolvimento , Técnicas de Cocultura , Eucariotos/metabolismo , Saccharomycetales/metabolismo
10.
Biomed Res Int ; 2017: 5806832, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28798932

RESUMO

Lycium barbarum polysaccharides (LBPs) have been shown to play a key role in protecting the eyes by reducing the apoptosis induced by certain types of damage. However, it is not known whether LBPs can protect damaged corneal cells from apoptosis. Moreover, no reports have focused on the role of LBPs in guarding against ultraviolet B- (UVB-) induced apoptosis. The present study aimed to investigate the protective effect and underlying mechanism of LBPs against UVB-induced apoptosis in rat corneal epithelial (RCE) cells. The results showed that LBPs significantly prevented the loss of cell viability and inhibited cell apoptosis induced by UVB in RCE cells. LBPs also inhibited UVB-induced loss of mitochondrial membrane potential, downregulation of Bcl-2, and upregulation of Bax and caspase-3. Finally, LBPs attenuated the phosphorylation of c-Jun NH2-terminal kinase (JNK) triggered by UVB. In summary, LBPs protect RCE cells against UVB-induced damage and apoptosis, and the underlying mechanism involves the attenuation of the mitochondrial apoptosis pathway and the inhibition of JNK phosphorylation.


Assuntos
Apoptose , Córnea/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Células Epiteliais/metabolismo , Lycium/química , MAP Quinase Quinase 4/metabolismo , Sistema de Sinalização das MAP Quinases , Mitocôndrias/metabolismo , Raios Ultravioleta/efeitos adversos , Animais , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Córnea/patologia , Medicamentos de Ervas Chinesas/química , Células Epiteliais/patologia , Feminino , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos da radiação , Mitocôndrias/patologia , Fosforilação/efeitos dos fármacos , Fosforilação/efeitos da radiação , Ratos , Ratos Wistar
11.
Arq. bras. oftalmol ; 85(4): 389-398, July-Aug. 2022. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1383816

RESUMO

ABSTRACT Purpose: To systematically examine the dynamic changes and time sequence in corneal epithelial cell apoptosis after excessive ultraviolet B irradiation. Methods: Ultraviolet B (144 mJ/cm2) was used to irradiate rat corneal epithelial cells for 2 h. Cell morphology was observed on differential interference contrast microscopy, and the numbers of the different kinds of apoptotic cells were counted using the ImageJ software. Cell viability was measured with the 3-(4,5-dimethyl-2-thiazolyl)-2,5- diphenyl-2-H-tetrazolium bromide method. Cell apoptotic rate and loss of mitochondrial membrane potential were detected using flow cytometric analyses. The expression levels of 3 apoptotic genes were measured with real-time quantitative polymerase chain reaction at different time points within 0-24 h after irradiation. Results: After 144-mJ/cm2 ultraviolet B irradiation for 2 h, the expression levels of caspase-8 and Bax were highest at 0 h; furthermore, the mitochondrial membrane potential decreased at 0 h and remained constant for 6 h in a subsequent culture. At 6 h, caspase-3 was activated. The decrease in cell viability and increase in apoptotic rate peaked at 6 h. The caspase-3 expression level decreased within 12-24 h, which led to a decline in apoptotic rate and change in apoptotic stage. Conclusions: The corneal epithelial cells exhibited rapid apoptosis after ultraviolet B irradiation, which was associated with both extrinsic and intrinsic pathways.


RESUMO Objetivos: Explorar sistematicamente as mudanças dinâmicas e a sequência temporal no processo de apoptose de células epiteliais corneanas após excesso de irradiação com ultravioleta B. Métodos: A radiação ultravioleta B (144 mJ/cm2) foi utilizada para irradiar células epiteliais da córnea de rato durante 2h. A morfologia celular foi observada por meio de microscópio de contraste de interferência diferencial, e os números de diferentes tipos de células apoptóticas foram contados e registrados pelo software ImageJ. A viabilidade celular foi medida pelo método brometo de 3- (4, 5-dimetil-2-tiazolil) -2, 5-difenil-2-H-tetrazólio. A taxa apoptótica celular e a perda do potencial da membrana mitocondrial foram detectadas por meio de análises citométricas de fluxo. Os níveis de expressão de três genes apoptóticos foram medidos por reação em cadeia da polimerase quantitativa em tempo real em diferentes momentos dentro de 0-24 h após a irradiação. Resultados: Após 144 mJ/cm2 de irradiação com ultravioleta B por 2h, os níveis de expressão de caspase-8 e Bax foram maiores em 0h; o potencial da membrana mitocondrial diminuiu a 0h e permaneceu constante por 6h na cultura subsequente. Às 6h, a caspase-3 foi ativada. A diminuição da viabilidade celular e o aumento da taxa apoptótica atingiu o pico em 6h. A expressão de caspase-3 diminuiu dentro de 12 - 24 h, levando a um declínio na taxa apoptótica e alteração no estágio apoptótico. Conclusões: As células epiteliais da córnea apresentaram uma apoptose rápida após excesso de irradiação com ultravioleta B, e esse processo foi associado tanto à via extrínseca como à via intrínseca.

12.
Sci Rep ; 6: 26944, 2016 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-27240678

RESUMO

Most common plant oils have little α-linolenic acid (C18:3(Δ9,12,15), ALA) and an unhealthy ω6/ω3 ratio. Here, fatty acids (FAs) in the seeds of 11 species of Paeonia L., including 10 tree peony and one herbaceous species, were explored using gas chromatograph-mass spectrometer. Results indicated that all Paeonia had a ω6/ω3 ratio less than 1.0, and high amounts of ALA (26.7-50%), oleic acid (C18:1(Δ9), OA) (20.8-46%) and linoleic acid (C18:2(Δ9,12), LA) (10-38%). ALA was a dominant component in oils of seven subsection Vaginatae species, whereas OA was predominant in two subsection Delavayanae species. LA was a subdominant oil component in P. ostii and P. obovata. Moreover, the FA composition and distribution of embryo (22 FAs), endosperm (14 FAs) and seed coat (6 FAs) in P. ostii, P. rockii and P. ludlowii were first reported. Peony species, particularly P. decomposita and P. rockii, can be excellent plant resources for edible oil because they provide abundant ALA to balance the ω6/ω3 ratio. The differences in the ALA, LA and OA content proportion also make the peony species a good system for detailed investigation of FA biosynthesis pathway and ALA accumulation.


Assuntos
Ácido Linoleico/metabolismo , Ácido Oleico/metabolismo , Paeonia/metabolismo , Sementes/metabolismo , Ácido alfa-Linolênico/metabolismo , Ácidos Graxos/classificação , Ácidos Graxos/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Ácido Linoleico/isolamento & purificação , Metabolismo dos Lipídeos , Ácido Oleico/isolamento & purificação , Paeonia/química , Óleos de Plantas/química , Sementes/química , Ácido alfa-Linolênico/isolamento & purificação
13.
Zhongguo Zhen Jiu ; 34(8): 751-4, 2014 Aug.
Artigo em Zh | MEDLINE | ID: mdl-25335248

RESUMO

OBJECTIVE: To observe the clinical efficacy difference between segmentation scraping and conventional acupuncture for cervical spondylosis (CS) so as to provide effective treatment method. METHODS: Eighty-five cases of cervical type of CS were randomly divided into a scraping group (44 cases) and an acupuncture group (41 cases). The segmentation scraping therapy was used in the scraping group. The scraping group was treated with focusing on scraping the head and joint part of neck and occiput in the upper cervical spine injury, and focusing on scraping the lower section of cervical and shoulder in the lower cervical spine injury, once every seven days, totally for 3 times. In the acupuncture group, Fengchi (GB 20),Wangu (TE 5), Tianzhu (BL 10),Neck-Jiaji (EX-B 2), etc. were selected,once daily,for 15 days. The visual analogue scale (VAS) was used to evaluate the immediate analgesic effect after the first treatment and the clinical efficacy was observed after the end of treatment. RESULTS: After the first treatment, the score of VAS was decreased significantly in the scaping group (P < 0.01), but there was no significant difference in the acupuncture group compared with those before treatment (P > 0.05); the score of VAS in the scaping group after the first treatment was lower than that in the acupuncture group (3.66 +/- 0.74 vs 5.43 +/- 0.35, P < 0.01). Compared with before treatment, the scores of VAS were decreased significantly after treatment in two groups (both P < 0.01), but without significant difference between two groups (P > 0.05); the effective rate was 95.5% (42/44) in the scaping group and 87.8% (36/41) in the acupuncture group, the curative effects were similar (P > 0.05). CONCLUSION: Both of scraping and acupuncture therapies have good analgesic effect for cervical spondylosis, and overall effects are similar, but the immediate analgesic effect of scraping thrapy is better than that of conventional acupuncture.


Assuntos
Pontos de Acupuntura , Terapia por Acupuntura , Medicina Tradicional Chinesa , Cervicalgia/terapia , Espondilose/terapia , Feminino , Humanos , Masculino , Resultado do Tratamento
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