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1.
J Colloid Interface Sci ; 635: 323-335, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36599234

RESUMO

Photocatalytic oxidation (PCO) of volatile organic compounds (VOCs) over MOF-based photocatalysts is considerably impeded by the weak activation of reactant molecules on the catalyst surface and low charge carrier mobility. In this study, we demonstrate that atomically dispersed Ti species anchored on NH2-UiO-66(Zr) (AUiO-66(Zr/Ti)) exhibit high visible-light-responsive photocatalytic activity toward toluene vapor with an 83 % removal efficiency and 89 % CO2 selectivity. These results are markedly superior to those reported in the literature. More importantly, AUiO-66(Zr/Ti) exhibited excellent catalytic stability during a prolonged reaction, while its pristine AUiO-66(Zr) counterpart underwent rapid catalytic deactivation after a few hours. The optimized sample, AUiO-66(Zr/Ti)-4h, provided extended visible light absorption and enhanced charge carrier mobility due to ligand-to-linker metal charge transfer. Meanwhile, the defect-rich surface of AUiO-66(Zr/Ti)-4h facilitated the activation of H2O/toluene molecules into the critical intermediates of hydroxyl, benzoic acid, and maleic anhydride, which were effectively converted under visible light illumination. On the basis of the combined results of the PCO of toluene and material characterization, the structure - activity relationship and the related catalytic mechanism are discussed comprehensively.

2.
Dev Cell ; 56(12): 1770-1785.e12, 2021 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-33984269

RESUMO

Mitochondrial functions across different tissues are regulated in a coordinated fashion to optimize the fitness of an organism. Mitochondrial unfolded protein response (UPRmt) can be nonautonomously elicited by mitochondrial perturbation in neurons, but neuronal signals that propagate such response and its physiological significance remain incompletely understood. Here, we show that in C. elegans, loss of neuronal fzo-1/mitofusin induces nonautonomous UPRmt through multiple neurotransmitters and neurohormones, including acetylcholine, serotonin, glutamate, tyramine, and insulin-like peptides. Neuronal fzo-1 depletion also triggers nonautonomous mitochondrial fragmentation, which requires autophagy and mitophagy genes. Systemic activation of UPRmt and mitochondrial fragmentation in C. elegans via perturbing neuronal mitochondrial dynamics improves resistance to pathogenic Pseudomonas infection, which is supported by transcriptomic signatures of immunity and stress-response genes. We propose that C. elegans surveils neuronal mitochondrial dynamics to coordinate systemic UPRmt and mitochondrial connectivity for pathogen defense and optimized survival under bacterial infection.


Assuntos
Proteínas de Caenorhabditis elegans/genética , Caenorhabditis elegans/genética , GTP Fosfo-Hidrolases/genética , Mitocôndrias/genética , Neurônios/microbiologia , Animais , Autofagia/genética , Caenorhabditis elegans/microbiologia , Interações Hospedeiro-Parasita/genética , Mitocôndrias/microbiologia , Dinâmica Mitocondrial/genética , Mitofagia/genética , Neurônios/metabolismo , Pseudomonas/genética , Pseudomonas/patogenicidade , Estresse Fisiológico/genética , Resposta a Proteínas não Dobradas/genética
3.
Int J Nanomedicine ; 8: 3833-42, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24143088

RESUMO

Mesoporous silica nanoparticles (MSNs) were synthesized as a promising drug delivery carrier due to the large surface area and porous characteristics. Our previous study successfully recycled wastes from the liquid crystal display (LCD) industry as the silica precursor. In this study, we substantiated the possibility of applying this material as a drug carrier. MSNs synthesized from the extraction of wastes from the manufacture of LCD panels were characterized as having an average diameter of 100 nm, a surface area of 788 m(2)/g, a uniform pore size distribution of 3.8 nm, and a pore volume of up to 1.04 cm(3)/g. Methotrexate and camptothecin were entrapped in MSNs at about 33.88% and 75.12%, respectively. The cell viability assay demonstrated that MSNs at 1 µg/mL had no significant influence on human lung fibroblast (WI-38) cells or ovarian cancer (ES-2) cells. A lactate dehydrogenase assay also indicated no inflammation occurred. Moreover, a hemolytic erythrocyte test indicated that the dose range of <100 µg/mL showed that 5% of erythrocytes were affected. After exposure to biofluids, the ordered structure was slightly degraded. The results revealed that MSNs synthesized from extraction of wastes from the manufacture of LCD panels had a good entrapment capacity for hydrophobic drugs and controllable safety conditions; they may be applied as a drug delivery carrier.


Assuntos
Sobrevivência Celular/efeitos dos fármacos , Cristais Líquidos/química , Nanocápsulas/química , Reciclagem/métodos , Dióxido de Silício/química , Dióxido de Silício/farmacologia , Linhagem Celular , Terminais de Computador , Estudos de Viabilidade , Humanos , Resíduos Industriais/prevenção & controle , Nanocápsulas/administração & dosagem , Nanocápsulas/ultraestrutura , Nanoporos/ultraestrutura , Tamanho da Partícula , Porosidade
4.
Anticancer Res ; 33(9): 4067-71, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24023351

RESUMO

AIM: The study aimed to evaluate the association and interaction of ataxia telangiectasia mutated (ATM) genetic polymorphisms with lung cancer risk in Taiwan, where lung cancer is the primary cause of cancer-related death. MATERIALS AND METHODS: In this hospital-based matched case-control study, associations of up to seven ATM single nucleotide polymorphisms (rs600931, rs652311, rs227060, rs228589, rs227092, rs624366 and rs189037) with lung cancer risk were investigated among Taiwanese. In this study, 358 lung cancer patients and 716 age- and gender-matched healthy controls were genotyped and the genetic-lifestyle interaction were analyzed. RESULTS: The results showed that the percentages of GG, AG and AA for ATM rs652311 genotypes were significantly different at 34.6%, 48.9% and 16.5% in the lung cancer patient group and 39.9%, 51.0% and 9.1% in non-cancer control group, respectively. We further analyzed the genetic-lifestyle effects on lung cancer risk and found that the contribution of ATM rs652311 A allele-bearing genotypes to lung cancer susceptibility was enhanced in the cigarette smokers and not enhanced in the non-smokers (p=0.0045 and 0.2758, respectively). CONCLUSION: Our results provide evidence that the A allele of ATM rs652311 may be associated with lung cancer risk, and may enhance the effects of smoking habit on lung cancer development.


Assuntos
Proteínas Mutadas de Ataxia Telangiectasia/genética , Predisposição Genética para Doença , Genótipo , Neoplasias Pulmonares/genética , Fumar , Idoso , Sequência de Bases , Primers do DNA , Feminino , Humanos , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Polimorfismo de Nucleotídeo Único , Taiwan
5.
Anticancer Res ; 33(6): 2775-8, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23749940

RESUMO

To evaluate the association and interaction of genotypic polymorphism the gene for DNA-apurinic/apyrimidinic endonuclease (APEX1) with personal smoking habit and lung cancer risk in Taiwan, the polymorphic variants of APEX1, Asp(148)Glu (rs1130409), were analyzed in association with lung cancer risk, and their joint effect with personal smoking habits on lung cancer susceptibility was discussed. In this hospital-based case-control study, 358 patients with lung cancer and 716 cancer-free controls, frequency-matched by age and sex, were recruited and genotyped by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP). The results showed that the percentages of TT, TG and GG APEX1 Asp(148)Glu genotypes were not significantly different at 43.0%, 41.1% and 15.9% in the lung cancer patient group and 39.9%, 46.1% and 14.0% in non-cancer control group, respectively. We further analyzed the genetic-lifestyle effects on lung cancer risk and found the contribution of APEX1 Asp(148)Glu genotypes to lung cancer susceptibility was neither enhanced in the cigarette smokers nor in the non-smokers (p=0.3550 and 0.8019, respectively). Our results provide evidence that the non-synonymous polymorphism of APEX1 Asp(148)Glu may not be directly associated with lung cancer risk, nor enhance the effects of smoking habit on lung cancer development.


Assuntos
DNA Liase (Sítios Apurínicos ou Apirimidínicos)/genética , Neoplasias Pulmonares/epidemiologia , Neoplasias Pulmonares/genética , Fumar/efeitos adversos , Estudos de Casos e Controles , Reparo do DNA , Feminino , Predisposição Genética para Doença , Variação Genética , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Fatores de Risco , Taiwan/epidemiologia
6.
Environ Sci Technol ; 47(9): 4636-43, 2013 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-23521136

RESUMO

An efficient and economic approach is proposed for the fast and direct recovery of silica materials from photonic waste powder. Unlike the conventional alkaline fusion method for the extraction of silica from waste materials, this method possesses advantages of a rapid and low-energy-consumed process with total recovery yield. The obtained mesoporous silica material, denoted as MCM-41(DU)-F, was recovered directly from photonic waste powder at room temperature with the assistance of cationic surfactant, hydrofluoric acid, and ammonia hydroxide. The recycled MCM-41(DU)-F with a high specific surface area (788 m(2)/g), ordered mesoporous structure (4.5 nm), and large pore volume (1.1 cm(3)/g) was used as support of tetraethylenepentamine (TEPA) for the capture of CO2 from a flue gas stream. The results demonstrated that TEPA-impregnated MCM-41(DU)-F had an adsorption capacity of 120 mg of CO2/g of adsorbent. This is higher than the amount adsorbed by TEPA-MCM-41(NaSi) made from pure chemicals (113 mg of CO2/g of adsorbent) and TEPA-MCM-41(AF) made from alkaline fusion (112 mg of CO2/g of adsorbent) under the same testing conditions. This novel recycling process, which can improve cost effectiveness for the mass production of valuable mesoporous silica materials from cheap and abundant resources through convenient preparation steps, is surely beneficial from the viewpoint of economical use of photonic industrial waste powder.


Assuntos
Reciclagem , Dióxido de Silício , Fótons , Pós
7.
J Hazard Mater ; 192(1): 255-62, 2011 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-21641110

RESUMO

This study explored the possibility of recovering waste powder from photonic industry into two useful resources, sodium fluoride (NaF) and the silica precursor solution. An alkali fusion process was utilized to effectively separate silicate supernatant and the sediment. The obtained sediment contains purified NaF (>90%), which provides further reuse possibility since NaF is widely applied in chemical industry. The supernatant is a valuable silicate source for synthesizing mesoporous silica material such as MCM-41. The MCM-41 produced from the photonic waste powder (PWP), namely MCM-41(PWP), possessed high specific surface areas (1082 m(2)/g), narrow pore size distributions (2.95 nm) and large pore volumes (0.99 cm(3)/g). The amine-modified MCM-41(PWP) was further applied as an adsorbent for the capture of CO(2) greenhouse gas. Breakthrough experiments demonstrated that the tetraethylenepentamine (TEPA) functionalized MCM-41(PWP) exhibited an adsorption capacity (82 mg CO(2)/g adsorbent) of only slightly less than that of the TEPA/MCM-41 manufactured from pure chemical (97 mg CO(2)/g adsorbent), and its capacity is higher than that of TEPA/ZSM-5 zeolite (43 mg CO(2)/g adsorbent). The results revealed both the high potential of resource recovery from the photonic solid waste and the cost-effective application of waste-derived mesoporous adsorbent for environmental protection.


Assuntos
Resíduos Industriais , Dióxido de Silício/isolamento & purificação , Adsorção , Microscopia Eletrônica de Transmissão , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
8.
Respirology ; 16(1): 152-60, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20946336

RESUMO

BACKGROUND AND OBJECTIVE: The expression of Fc receptors for IgG (FcγRs) on neutrophils, including CD16, CD32 and CD64, may be modulated in response to sepsis. We investigated the expression of FcγRs on neutrophils and procalcitonin (PCT) as biomarkers of sepsis among critically ill patients. METHODS: This prospective study was conducted in a 24-bed respiratory intensive care unit between July 2007 and June 2008. Critically ill patients requiring mechanical ventilation were enrolled and categorized into three groups: those with systemic inflammatory response syndrome (SIRS), those with severe sepsis and those with septic shock. Expression of FcγRs on neutrophils was quantitatively measured by flow cytometry immediately after enrolment of the patient. Serum PCT levels were also measured. Receiver operating characteristic (ROC) curves were used to evaluate the performance of FcγR expression and PCT as biomarkers of sepsis. RESULTS: Sixty-six patients were enrolled, including 11 with SIRS, 31 with severe sepsis and 24 with septic shock. Nineteen healthy volunteers served as normal controls. CD64 was upregulated, CD16 was downregulated and CD32 remained unchanged during sepsis. CD64 expression and the ratio of CD64/CD16 increased significantly with the severity of sepsis. However, serum PCT levels were not significantly different between SIRS and severe sepsis patients. CD64, CD64/CD16 and PCT all significantly predicted sepsis, septic shock and bacteraemia. As assessed using ROC curves, CD64 was better than PCT for differentiating SIRS from severe sepsis and septic shock. CD64 and CD64/CD16 were associated with mortality. CONCLUSIONS: CD64 and CD16 were differentially modulated by sepsis. CD64, CD64/CD16 and PCT may be biomarkers of sepsis. CD64 was better than PCT for identifying patients who required treatment with antibiotics.


Assuntos
Calcitonina/sangue , Neutrófilos/imunologia , Precursores de Proteínas/sangue , Receptores de IgG/análise , Sepse/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Peptídeo Relacionado com Gene de Calcitonina , Doença Crônica , Comorbidade , Estado Terminal , Feminino , Citometria de Fluxo , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sepse/sangue , Sepse/mortalidade , Índice de Gravidade de Doença
9.
J Air Waste Manag Assoc ; 59(10): 1186-93, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19842326

RESUMO

This study delineates a simple and versatile approach for the removal of nitrogen monoxide (NO) and volatile organic vapors over composites of titanium dioxide (TiO2) catalyst/zeolite adsorbent under ultraviolet (UV) irradiation at ambient temperature. The catalytic adsorbents with different TiO2/H-ZSM-5 zeolite ratios were prepared by a simple insipient wetness impregnation method. It was found that a 60%/40% weight ratio of TiO2/H-ZSM-5 composite is most effective and can achieve over 90% efficiency for the removal of NO and acetone vapors. This composite also showed a better long-term activity than that of bulk TiO2 photocatalyst or zeolite adsorbent. The experimental results revealed that photocatalytic decomposition of NO was dramatically enhanced in the presence of acetone. NO also promoted the acetone oxidation under humid conditions. Furthermore, the co-existence of acetone and NO in the gaseous stream could reduce acid accumulation on the surface of the catalyst as confirmed by Fourier-transform infrared spectroscopy. Thus, the TiO2/zeolite catalytic adsorbent could have a high potential for the removal of multiple air pollutants in the indoor air environment.


Assuntos
Acetona/química , Óxido Nítrico/química , Titânio/química , Zeolitas/química , Adsorção , Catálise , Gases/química , Fotoquímica
10.
Respirology ; 14(4): 511-21, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19386070

RESUMO

BACKGROUND AND OBJECTIVE: The aim of this study was to characterize the changes in neutrophils and cytokines in BAL fluid following acute lung injury (ALI), and to determine the protective effect of post-injury treatment with IL-10. METHODS: A rat model of ALI was established by evenly spraying LPS (16 mg/kg) into the lungs followed by observation for 48 h. Histological changes and the kinetics of neutrophil infiltration were evaluated in the injured lungs. The cytokines (TNF-alpha, IL-6, IL-10 and interferon-gamma) and macrophage-inflammatory protein (MIP-2) were measured in BAL fluid by ELISA. The activation of BAL fluid neutrophils was investigated after treatment with IL-10 in vitro. The protective effect on histology and MIP-2 levels of intra-tracheal instillation of IL-10 12 and 16 h after LPS treatment was studied in vivo. RESULTS: Intra-tracheal instillation of LPS caused significant lung injury and the activation of neutrophils. The levels of TNF-alpha and IL-6 in BAL fluid peaked at 8 and 16 h after LPS instillation respectively. IL-10 levels reached a maximum at 16-24 h, at the beginning of resolution of tissue injury. IL-10 inhibited the activation of neutrophils in vitro and MIP-2 induction in vivo. IL-10 had a protective effect if it was administered 12 but not 16 h after LPS. CONCLUSIONS: Neutrophils appeared to play an important role in ALI. Time-dependent treatment with IL-10 after intra-tracheal instillation of LPS was effective in protecting rats from ALI, probably by suppressing pulmonary infiltration with activated neutrophils.


Assuntos
Lesão Pulmonar Aguda/tratamento farmacológico , Lesão Pulmonar Aguda/patologia , Interleucina-10/uso terapêutico , Lesão Pulmonar Aguda/metabolismo , Animais , Técnicas de Cultura de Células , Citocinas/metabolismo , Modelos Animais de Doenças , Instilação de Medicamentos , Interleucina-10/administração & dosagem , Lipopolissacarídeos , Masculino , Ativação de Neutrófilo/efeitos dos fármacos , Infiltração de Neutrófilos/efeitos dos fármacos , Neutrófilos/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Traqueia
11.
Shock ; 32(3): 276-85, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19106808

RESUMO

The pathophysiological role of soluble immune complexes (SICXs) and its relationship with neutrophils were investigated in LPS-induced acute lung injury (ALI) animal model (Sprague-Dawley rat) and through the in vitro studies. Results showed that LPS-induced SICX was timely related to changes of tumor necrosis factor alpha and macrophage inflammatory protein 2 (inflammatory cytokines) in bronchoalveolar lavage fluid. In vitro study showed that SICX can bind to Fc gammaR (CD64 and CD32 or CD16) to prevent the apoptosis of neutrophils. The SICX-mediated apoptosis inhibition was extracellular signal-regulated kinase (ERK) or phosphoinositide 3 kinase dependent and was interrupted by PD98059 and LY294002. In vivo, additional amount of SICX exacerbated the lung injury caused by LPS. LPS-induced lung injury and macrophage inflammatory protein 2 release, however, were prevented by CD64 and CD32 blockers (decoy antibodies). In conclusion, excessive amount of SICX in lung can act through Fc gammaRs to protect bronchoalveolar lavage fluid neutrophils from apoptosis that eventually lead to delayed resolution of ALI caused by LPS. Blockade of SICX engagement of CD32 and CD64 (with decoy antibodies) could interrupt SICX-mediated protection of neutrophils and protect lung from LPS-induced injury. The decoy antibodies may therefore have therapeutic utility in ALI.


Assuntos
Lesão Pulmonar Aguda/metabolismo , Complexo Antígeno-Anticorpo/fisiologia , Lipopolissacarídeos/farmacologia , Neutrófilos/citologia , Lesão Pulmonar Aguda/induzido quimicamente , Animais , Complexo Antígeno-Anticorpo/metabolismo , Apoptose/efeitos dos fármacos , Líquido da Lavagem Broncoalveolar/química , Quimiocina CXCL2/metabolismo , Cromonas/farmacologia , Inibidores Enzimáticos , Ensaio de Imunoadsorção Enzimática , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , MAP Quinases Reguladas por Sinal Extracelular/fisiologia , Flavonoides/farmacologia , Masculino , Morfolinas/farmacologia , Neutrófilos/efeitos dos fármacos , Ligação Proteica , Ratos , Ratos Sprague-Dawley , Receptores de IgG/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
12.
Respirology ; 12(3): 333-8, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17539835

RESUMO

BACKGROUND AND OBJECTIVE: The triggering receptor expressed on myeloid cell-1 (TREM-1) is a newly discovered molecule that is associated with the inflammatory response to microorganisms. We investigated the role of surface and soluble TREM-1 in differentiating different disease entities in pleural effusion formation. METHODS: Sixty-seven patients with pleural effusion due to transudate (14), malignancy (15), tuberculous pleuritis (16), para-pneumonic effusion (10) and empyaema (12) were included in this study. Surface TREM-1 was measured by flow cytometry and was expressed as mean fluorescence intensity and soluble TREM-1 was measured by ELISA and expressed as pg/mL. Results are given as mean levels +/- SEM. RESULTS: Surface TREM-1 was measured in 24 patients and the levels were highest in para-pneumonic effusion (30.0 +/- 8.4) and lowest in malignant pleural effusion (5.2 +/- 1.1) and tuberculous pleuritis (5.2 +/- 2.4). Soluble TREM-1 was highest in effusions of infectious aetiology (para-pneumonic effusion (979.4 +/- 229.6) and empyaema (1712.6 +/- 299.5)) and lowest in non-infectious effusions (transudate (81.2 +/- 4.5 pg/mL) and malignancy (111.3 +/- 20.7). At a cut-off value of 114 pg/mL, soluble TREM-1 yielded a sensitivity of 87.5% and a specificity of 89.7% in differentiating non-infectious effusion from tuberculous pleuritis. At a cut-off value of 374 pg/mL, sTREM-1 yielded a sensitivity of 93.8% and a specificity of 90.9 in differentiating tuberculous pleuritis from bacterial pleural effusion. CONCLUSION: Soluble and surface TREM-1 are valuable markers in establishing the aetiology of pleural effusions.


Assuntos
Glicoproteínas de Membrana/metabolismo , Derrame Pleural/diagnóstico , Derrame Pleural/metabolismo , Receptores Imunológicos/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/metabolismo , Empiema/complicações , Exsudatos e Transudatos , Feminino , Humanos , Neoplasias Pulmonares/complicações , Masculino , Pessoa de Meia-Idade , Derrame Pleural/etiologia , Pneumonia/complicações , Sensibilidade e Especificidade , Receptor Gatilho 1 Expresso em Células Mieloides , Tuberculose Pleural/complicações
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