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1.
J Formos Med Assoc ; 123(3): 331-339, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37996329

RESUMO

BACKGROUND AND PURPOSE: We present this current study to complement with mesh inlays plausible benefits (UPHOLD-LITE System) on available long-term study amidst FDA's concern on mesh complications. This study aims to assess the medium-term outcomes of UPHOLD-LITE system for treatment of advanced pelvic organ prolapse (POP) and its complications, and lower urinary tract symptoms. METHODS: This is a retrospective case series of 53 months follow-up of 123 consecutive patients who underwent UPHOLD-LITE system. Objective outcome measures the anatomical correction of prolapse with POP-Q ≤ Stage 1. Subjective outcome was patient's feedback to questions 2 and 3 of POPDI-6. Secondary outcome measures the quality of life, presence of lower urinary tract symptoms and complications. Quality of life is assessed by validated questionnaires on Urogenital Distress Inventory 6 (UDI-6), Incontinence Impact Questionnaire 7 (IIQ-7), Pelvic Organ Prolapse Distress Inventory 6 (POPDI-6), and Pelvic Organ Prolapse/Urinary Incontinence Sexual Function Questionnaire 12 (PISQ-12) at 1 and 3 years post-operatively. RESULTS: Objective outcome at 1 and 3 years was at 96.7 % and 95.4 % respectively. The subjective cure was 95.1 % and 91.6 %. Five-year cumulative cure rate maintained at 87.2 %. Secondary outcomes observed improvement on UDI-6, IIQ-7, POPDI-6 and PISQ-12 postoperatively. Bladder outlet obstruction improved while de novo urodynamic stress incontinence (USI) increased slightly post surgically. Mesh erosion rate was 0.8 %. CONCLUSION: The UPHOLD-LITE system demonstrated good medium term anatomical correction of apical and anterior prolapse, with good subjective cure and improved quality of life. Whilst complication rate was low, slight increase in de novo USI was observed.


Assuntos
Prolapso de Órgão Pélvico , Incontinência Urinária por Estresse , Incontinência Urinária , Humanos , Feminino , Seguimentos , Resultado do Tratamento , Polipropilenos , Estudos Retrospectivos , Qualidade de Vida , Telas Cirúrgicas , Prolapso de Órgão Pélvico/cirurgia , Incontinência Urinária/cirurgia , Inquéritos e Questionários
2.
Int Urogynecol J ; 32(10): 2737-2745, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34292341

RESUMO

INTRODUCTION AND HYPOTHESIS: The objective was to identify incidence and risk factors of de novo urgency and detrusor overactivity (DO) following mid-urethral slings (MUS) in patients with urodynamic stress incontinence (USI) without urgency. METHODS: A total of 688 women between January 2004 and July 2017 were reviewed retrospectively. De novo urgency was established with a positive response to question 2 on the Urogenital Distress Inventory-6 questionnaire (UDI-6). Objective cure of USI is no involuntary urine leakage during filling cystometry and pad test < 2 g. Subjective cure of stress urinary incontinence (SUI) is defined as a negative response to question 3 on UDI-6. Multivariate logistic regression was used to identify risk factors for failure. RESULTS: Forty-four out of 688 women (6.4%) developed de novo urgency, with 16 out of 688 (2.3%) demonstrating de novo DO. Subjective cure for women with de novo urgency was significantly lower at 35 out of 44 (79.5%) compared with 556 out of 644 (86.3%) in those with no urgency (p < 0.001). Objective cure for women with de novo DO was significantly lower at 8 out of 16 (50%) compared with 599 out of 672 (89.1%) in those with detrusor stability (p < 0.001). Quality of life improved for all. Age ≥ 66 (OR, 1.23; 1.07), increased bladder sensation (OR, 4.18; 3.80), lower bladder capacity (OR, 5.28; 4.97), lower maximum urethral closure pressure (OR, 2.32; 5.20), and pad test > 100 g (OR, 1.08; 1.15) were independent risk factors for de novo urgency and DO. Diabetes (OR, 1.32) was an independent predictor of de novo urgency. CONCLUSION: Cure is significantly reduced in women who report symptoms of de novo urgency or demonstrate DO after MUS at 1 year. Independent risk factors include age ≥ 66, increased bladder sensation, lower bladder capacity, lower maximum urethral closure pressure, greater pad loss, and diabetes.


Assuntos
Slings Suburetrais , Incontinência Urinária por Estresse , Feminino , Humanos , Qualidade de Vida , Estudos Retrospectivos , Slings Suburetrais/efeitos adversos , Incontinência Urinária por Estresse/cirurgia , Urodinâmica
3.
J Inorg Biochem ; 215: 111329, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33321394

RESUMO

At present, cancer has become a major disease threatening human health worldwide. Therefore, developing targeting guided multimode synergetic therapy has become one of the hot spots in current antitumor research and is also a great challenge. Herein, a new Fe3O4/g-C3N4@PPy-DOX nanocomposite containing magnetic iron oxide (Fe3O4) nanoparticles (NPs), lamellar structure of graphite-like carbon nitride (g-C3N4) and polypyrrole (PPy) shell with the loaded anti-tumor drug doxorubicin hydrochloride (DOX) was designed and prepared. The monodisperse Fe3O4 nanoparticles (NPs) with the diameter of 20 nm endowed the nanocomposite with the magnetic targeting ability, reducing damage to normal tissues. It is very interesting that the Fe3O4 NPs also possessed photosensitizer function for photodynamic therapy (PDT). The g-C3N4 sheets as the photocatalysis towards the degradation of water for generating O2 could effectively improve the hypoxia of solid tumors and increase the efficiency of PDT. In addition, PPy has high light-to-heat conversion efficiency, so was chosen for the cancer photothermal therapy (PTT). Finally, an anticancer drug (DOX) was loaded on the nanocomposite because the presence of mesoporous structure. Thus, the prepared Fe3O4/g-C3N4@PPy-DOX nanocomposites exhibit synergetic chemotherapy/PTT/enhanced PDT antitumor effect. This study provides an inspiration for combining targeting and multimodality to improve the anticancer efficiency.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Doxorrubicina/farmacologia , Grafite/química , Nanopartículas Magnéticas de Óxido de Ferro/química , Nanocompostos/química , Neoplasias/tratamento farmacológico , Compostos de Nitrogênio/química , Polímeros/química , Pirróis/química , Protocolos de Quimioterapia Combinada Antineoplásica/química , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/química , Células Hep G2 , Humanos , Hipertermia Induzida/métodos , Hipóxia/metabolismo , Neoplasias/metabolismo , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/química , Fototerapia/métodos
4.
Nanotechnology ; 27(14): 145701, 2016 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-26903086

RESUMO

P-nitrophenol (4-NP) and hydrazine hydrate are considered to be highly toxic pollutants in wastewater, and it is of great importance to remove them. Herein, TiO2-loaded Co0.85Se thin films with heterostructure were successfully synthesized by a hydrothermal route. The as-synthesized samples were characterized by x-ray diffraction, x-ray photoelectron spectroscopy, transmission electron microscopy and selective-area electron diffraction. The results demonstrate that TiO2 nanoparticles with a size of about 10 nm are easily loaded on the surface of graphene-like Co0.85Se nanofilms, and the NH3 · H2O plays an important role in the generation and crystallization of TiO2 nanoparticles. Brunauer-Emmett-Teller measurement shows that the obtained nanocomposites have a larger specific surface area (199.3 m(2) g(-1)) than that of Co0.85Se nanofilms (55.17 m(2) g(-1)) and TiO2 nanoparticles (19.49 m(2) g(-1)). The catalytic tests indicate Co0.85Se-TiO2 nanofilms have the highest activity for 4-NP reduction and hydrazine hydrate decomposition within 10 min and 8 min, respectively, compared with the corresponding precursor Co0.85Se nanofilms and TiO2 nanoparticles. The enhanced catalytic performance can be attributed to the larger specific surface area and higher rate of interfacial charge transfer in the heterojunction than that of the single components. In addition, recycling tests show that the as-synthesized sample presents stable conversion efficiency for 4-NP reduction.

5.
PLoS One ; 9(9): e109876, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25264621

RESUMO

BACKGROUND: Conventional reverse transcription-polymerase chain reaction (RT-PCR) amplification of the RNA-dependent RNA polymerase (RdRp) gene remains a used method for the rapid detection of norovirus (NV) in clinical laboratories. The incidence of and factors associated with false positives in this assay have not been previously evaluated. METHODS/PRINCIPAL FINDINGS: After an NV outbreak caused by the GII.4 Sydney strain in 2012, we reanalysed 250 stool samples positive for NV by RdRp gene detection. True positives were confirmed in 154 (61.6%) samples by successful amplification and sequencing confirmation of the viral protein 1 gene. Of the remaining 96 samples that underwent RT-PCR for the RdRp gene, 34 samples yielded PCR products of the expected length. However, the sequences of the amplicons belonged to the human genome, with 91-97% matched nucleotide sequences, indicating false positives. Multivariate analysis of the clinical features of the patients identified a positive stool culture for bacteria (adjusted odds ratio [aOR] 9.07, 95% adjusted confidence interval [aCI] 2.17-37.92, P = .003) and the use of parenteral antibiotics (aOR 5.55, 95% aCI 1.21-24.73, P = .027) as significant and independent factors associated with false positives. CONCLUSION: Conventional RT-PCR targeting the RdRp gene of NV can lead to false positives in patients with bacterial enterocolitis by incidental amplification of DNA from a human source.


Assuntos
Infecções por Caliciviridae/diagnóstico , Infecções por Caliciviridae/epidemiologia , Técnicas de Laboratório Clínico/métodos , Gastroenterite/diagnóstico , Norovirus/enzimologia , RNA Polimerase Dependente de RNA/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Sequência de Bases , Infecções por Caliciviridae/virologia , Pré-Escolar , Demografia , Eletroforese em Gel de Ágar , Reações Falso-Positivas , Feminino , Gastroenterite/epidemiologia , Gastroenterite/virologia , Humanos , Incidência , Modelos Logísticos , Masculino , Norovirus/genética , Filogenia , Fatores de Risco
6.
ACS Appl Mater Interfaces ; 6(17): 15052-60, 2014 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-25144940

RESUMO

In this paper, we report a novel matchlike zinc oxide (ZnO)/gold (Au) heterostructure with plasmonic-enhanced photoelectrochemical (PEC) activity for solar hydrogen production. The matchlike heterostructure with Au nanoparticles coated on the tip of ZnO nanorods is in situ grown on a zinc (Zn) substrate by using a facile hydrothermal and photoreduction combined approach. This unique heterostructure exhibits plasmonic-enhanced light absorption, efficient charge separation and transportation properties with tunable Au contents. The photocurrent density of the matchlike ZnO/Au heterostructure reaches 9.11 mA/cm(2) at an applied potential of 1.0 V (vs Ag/AgCl) with an Au/Zn atomic ratio of 0.039, which is much higher than that of the pristine ZnO nanorod array (0.33 mA/cm(2)). Moreover, the solar-to-hydrogen conversion efficiency of this special heterostructure can reach 0.48%, 16 times higher than that of the pristine ZnO nanorod array (0.03%). What is more, the efficiency could be further improved by optimizing the Au content of the heterostructure. The formation mechanism of such a unique heterostructure is proposed to explain the plasmonic-enhanced PEC performance. This study might contribute to the rational design of the visible-light-responsive plasmonic semiconductor/metal heterostructure photoanode to harvest the solar spectrum.

7.
Dalton Trans ; 43(10): 3978-83, 2014 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-24452313

RESUMO

In this work, we present novel kinds of Fe3O4@Tb-BTC magnetic metal-organic framework (MOF) nanospheres which possess both magnetic characteristics and fluorescent properties using a layer by layer assembly technique. The structure and morphology of the as-prepared Fe3O4@Tb-BTC were systematically characterized and it was applied in detection of nitroaromatic explosives, such as 2,4-dinitrotoluene (2,4-DNT), 2,6-dinitrotoluene (2,6-DNT), 2-nitrotoluene (2-NT), 4-nitrotoluene (4-NT), nitrobenzene (NB) and picric acid (PA). The results indicate that the fluorescence intensity of Fe3O4@Tb-BTC can be quenched by all analytes studied in the present work. Remarkably, the as-synthesized nanospheres exhibit high sensitivity for 2,4,6-trinitrotoluene (TNT) detection with Ksv value of (94 800 M(-1)). Besides, the magnetic nanospheres can be easily recycled, which makes it more convenient for reutilization and friendly to the environment. The results show that it has broad application prospects in the detection of nitroaromatic explosives.

8.
Dalton Trans ; 43(9): 3792-8, 2014 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-24448232

RESUMO

Metal-organic frameworks (MOFs) MIL-88A hexagonal microrods as a new photocatalyst show an active performance for methylene blue (MB) dye decolorization using visible light. MB decolorization over the MIL-88A photocatalyst follows first-order kinetics. The addition of a H2O2 electron acceptor can markedly enhance the photocatalytic MB decoloration performance of MIL-88A. Moreover, MIL-88A showed a very stable activity for MB decoloration after four consecutive usages. Owing to the advantages of the visible light response, low cost and abundance in nature, this active MIL-88A MOF photocatalyst would have great potential for environmental purification.

9.
J Biotechnol ; 168(4): 527-33, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24070903

RESUMO

FIP-fve is a bioactive protein isolated from the mushroom Flammulina velutipes, which belongs to the fungal immunomodulatory protein (FIP) family and demonstrates several kinds of biological activities including anti-allergy, anti-tumor and immunomodulation. In the current study, the FIP-fve gene was cloned and expressed in the yeast Pichia pastoris GS115, and its correctness was confirmed by SDS-PAGE and Western blot. Optimal expression of rFIP-fve was observed when the P. pastoris cells were cultured in 1% methanol for 9 6h, which resulted in a yield of 258.2 mg l(-1). The rFIP-fve protein was subsequently purified via ammonium sulfate precipitation and Sephadex G-100 gel chromatography. In vitro bioactivity examination showed that rFIP-fve could agglutinate human red blood cells and stimulate the cell viability of murine splenocytes. The immunomodulatory capacity and anti-tumor activity of rFIP-fve were demonstrated by enhanced interleukin-2 secretion and interferon-γ release from the murine lymphocytes, similar to the biological FIP-fve. In conclusion, the FIP-fve gene was functionally and effectively expressed in P. pastoris, and rFIP-fve displayed biological activities similar to those of native FIP-fve. These results indicated the potential use of rFIP-fve from P. pastoris as an effective and feasible source for therapeutic studies and medical applications.


Assuntos
Flammulina/genética , Proteínas Fúngicas/biossíntese , Pichia/genética , Proteínas Recombinantes/biossíntese , Animais , Eritrócitos/efeitos dos fármacos , Flammulina/crescimento & desenvolvimento , Proteínas Fúngicas/genética , Proteínas Fúngicas/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Interferon gama/metabolismo , Interleucina-2/metabolismo , Linfócitos/efeitos dos fármacos , Linfócitos/metabolismo , Camundongos , Proteínas Recombinantes/genética , Proteínas Recombinantes/farmacologia
10.
J Hazard Mater ; 221-222: 147-54, 2012 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-22560174

RESUMO

Covalent organic frameworks (COFs) are a new generation of porous materials constructed from light elements linked by strong covalent bonds. Herein we present rapid preparation of highly fluorescent nanoparticles of a new type of COF, i.e. melamine-based porous polymeric network SNW-1, by a microwave-assisted synthesis route. Although the synthesis of SNW-1 has to be carried out at 180°C for 3d under conventional reflux conditions, SNW-1 nanoparticles could be obtained in 6h by using such a microwave-assisted method. The results obtained have clearly demonstrated that microwave-assisted synthesis is a simple yet highly efficient approach to nanoscale COFs or other porous polymeric materials. Remarkably, the as-synthesized SNW-1 nanoparticles exhibit extremely high sensitivity and selectivity, as well as fast response to nitroaromatic explosives such as 2,4,6-trinitrotoluene (TNT), 2,4,6-trinitrophenylmethylnitramine (Tetryl) and picric acid (PA) without interference by common organic solvents, which is due to the nanoscaled size and unique hierarchical porosity of such fluorescence-based sensing material.


Assuntos
Substâncias Explosivas/análise , Micro-Ondas , Nanopartículas , Triazinas/química , Fluorescência , Limite de Detecção , Microscopia Eletrônica de Transmissão , Espectrometria de Fluorescência , Espectrofotometria Infravermelho
11.
Dalton Trans ; 41(22): 6756-63, 2012 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-22532247

RESUMO

The g-C(3)N(4)-ZnO composite photocatalysts with various weight percents of ZnO were synthsized by a simple calcination process. The photocatalysts were characterized by powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HR-TEM), UV-vis diffuse reflection spectroscopy (UV-vis), X-ray photoelectron spectroscopy (XPS) and thermogravimetric analysis (TGA). The PXRD and HR-TEM results show that the composite materials consist of hexagonal wurzite phase ZnO and g-C(3)N(4). The solid-state UV-vis diffuse reflection spectra show that the absorption edge of the composite materials shifts toward the lower energy region and to longer wavelengths in comparison with pure ZnO and g-C(3)N(4). Remarkably, the photocatalytic activity of g-C(3)N(4)-ZnO composites has been demonstrated, via photodegradation of Methyl Orange (MO) and p-nitrophenol experiments. The photocatalytic activity of g-C(3)N(4)-ZnO for photodegradation of Methyl Orange and p-nitrophenol under visible light irradiation was increased by over 3 and 6 times, respectively, to be much higher than that of single-phase g-C(3)N(4), clearly demonstrating a synergistic effect between ZnO and g-C(3)N(4). The concentrations of Zn(2+) in g-C(3)N(4)-ZnO system after a photocatalytic reaction at various reaction times were found to be much lower than those for a ZnO system under the same reaction conditions, indicating that the g-C(3)N(4)-ZnO composite possesses excellent long-term stability for a photocatalytic reaction in aqueous solutions. Furthermore, a synergistic photocatalysis mechanism between ZnO and g-C(3)N(4) was proposed based on the photodegradation results. Such obviously improved performance of g-C(3)N(4)-ZnO can be ascribed mainly to the enhancement of electron-hole separations at the interface of ZnO and g-C(3)N(4).

12.
Chin Med J (Engl) ; 124(16): 2522-9, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21933599

RESUMO

BACKGROUND: Retinal pigment epithelial (RPE) cell is a monolayer of multifunctional cells between the retina and the choroid. Peroxynitrite (ONOO(-)) is known to induce toxicity on RPE cells. This study aimed to evaluate ONOO(-) induced expression of inducible nitric oxide synthase (iNOS) and complement 3 (C3) via Fas/FasL pathway in RPE cells and the values of puerarin as a therapeutic target for inhibiting the apoptosis of RPE cells. METHODS: RPE cells were obtained from eyes of C57BL/6 mice. RPE cells were divided into control, ONOO(-) and puerarin groups. Control group was treated with saline, ONOO(-) group was treated with ONOO(-), and puerarin group was treated with puerarin after added with ONOO(-). All changes were observered at 6, 12 and 24 hours after treatment. Western blotting analysis was used to determine the expression of nitrotyrosine (NT, the foot print of ONOO(-)) and C3; flow cytometry was used to determine the apoptosis of RPE cells. Immunohistochemistry and Western blotting were used to determine Fas/FasL signal transduction. Gene array analysis, reverse transcription polymerase chain reaction (RT-PCR) and Western blotting were used to determine the expression of iNOS mRNA and iNOS protein in RPE cells. RESULTS: There were minor expression of NT, C3, Fas/FasL and iNOS mRNA in control group, and strong expression of NT and C3 in ONOO(-) group, while in puerarin group weak expressions of NT and C3 were detected as time passed by (P < 0.001). Apoptosis of RPE cells occured and reached a higher level at 6 and 24 hours after addition of ONOO(-) respectively in ONOO(-) group, but delayed apoptosis in puerarin group (P < 0.05). Compared to control group, the expression of Fas/FasL was up-regulated in ONOO(-) group, but was down-regulated in puerarin group (P < 0.001). Similarly, the expressions of iNOS mRNA and iNOS protein in ONOO(-)group were up-regulated in ONOO(-) group, but down-regulated in puerarin group (P < 0.001). CONCLUSIONS: ONOO(-) expresseion in RPE cells may constitute the new way of oxidant stress. Fas/FasL signal transduction pathway and C3 may affect and reinforce apoptosis mediated by ONOO(-). Puerarin could reverse ONOO(-) damage on RPE cells. The antagonizing mechanism of puerarin may be related to its inhibitory to the expression of iNOS mRNA, and therefore decrease ONOO(-) formation as well as directly antagonize the effect of ONOO(-). Furthermore, puerarin may be an useful therapeutic agent against apoptosis of RPE cells.


Assuntos
Complemento C3/metabolismo , Células Epiteliais/metabolismo , Proteína Ligante Fas/metabolismo , Isoflavonas/farmacologia , Óxido Nítrico Sintase Tipo II/metabolismo , Ácido Peroxinitroso/farmacologia , Epitélio Pigmentado Ocular/citologia , Receptor fas/metabolismo , Animais , Western Blotting , Células Cultivadas , Complemento C3/genética , Células Epiteliais/efeitos dos fármacos , Proteína Ligante Fas/genética , Citometria de Fluxo , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos C57BL , Óxido Nítrico Sintase Tipo II/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Receptor fas/genética
13.
J Hazard Mater ; 196: 36-43, 2011 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-21924826

RESUMO

The presence of coordinatively unsaturated metal centers in metal-organic frameworks (MOFs) provides an accessible way to selectively functionalize MOFs through coordination bonds. In this work, we describe thiol-functionalization of MOFs by choosing a well known three-dimensional (3D) Cu-based MOF, i.e. [Cu(3)(BTC)(2)(H(2)O)(3)](n) (HKUST-1, BTC=benzene-1,3,5-tricarboxylate), by a facile coordination-based postsynthetic strategy, and demonstrate their application for removal of heavy metal ion from water. A series of [Cu(3)(BTC)(2)](n) samples stoichiometrically decorated with thiol groups has been prepared through coordination bonding of coordinatively unsaturated metal centers in HKUST-1 with -SH group in dithioglycol. The obtained thiol-functionalized samples were characterized by powder X-ray diffraction, scanning electron microscope, energy dispersive X-ray spectroscopy, infrared spectroscopy, and N(2) sorption-desorption isothermal. Significantly, the thiol-functionalized [Cu(3)(BTC)(2)](n) exhibited remarkably high adsorption affinity (K(d)=4.73 × 10(5)mL g(-1)) and high adsorption capacity (714.29 mg g(-1)) for Hg(2+) adsorption from water, while the unfunctionalized HKUST-1 showed no adsorption of Hg(2+) under the same condition.


Assuntos
Mercúrio/isolamento & purificação , Compostos Organometálicos/química , Compostos de Sulfidrila/química , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Adsorção , Cinética , Estruturas Metalorgânicas , Microscopia Eletrônica de Varredura , Espectrofotometria Infravermelho , Propriedades de Superfície , Difração de Raios X
14.
Dalton Trans ; 40(25): 6745-50, 2011 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-21625672

RESUMO

A novel and facile protocol for the rapid synthesis of flower-like Cu(2)O architectures is reported in the presence of ionic liquid 1-n-butyl-3-methyl imidazolium tetrafluoroborate ([BMIM]BF(4)) with the assistance of microwave irradiation. The hierarchical structures are assembled from many thin nanosheets with tunable sizes by adjusting the amount of [BMIM]BF(4) in the reaction solution. Noticeably, the flower-like Cu(2)O architectures present a high surface area of 65.77 cm(2) g(-1) with a band gap of about 2.25 eV, and exhibit high and stable photochemical activity for the reduction of Cr(VI) to Cr(III) under visible light irradiation. A reasonable model of an absorption and diffusion-limited aggregation process is proposed for explaining the possible formation mechanism of the flower-like Cu(2)O. The approach described in this study provides a feasible and rapid method to synthesize flower-like Cu(2)O with a hierarchical structure that is ready for application in the fields of photocatalytic hazard pollutants.

15.
Zhonghua Yan Ke Za Zhi ; 47(4): 320-6, 2011 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-21612681

RESUMO

OBJECTIVE: The therapeutic effects of general and local applications of puerarin in the treatment of streptozotocin (STZ)-induced rat diabetic model were compared. METHODS: Experimental research. We equally divided normal Sprague-Dawley (SD) rats into a STZ group, a peritoneal injection group, a peribulbar injection group and a control group. STZ, peritoneal injection and peribulbar injection groups were first treated with STZ. Subsequently, the STZ group was injected with normal saline intraperitoneally, while in the later two groups puerarin was injected through peritoneal and peribular routes, respectively. Control group only received peritoneal injection of saline. The morphology of lens epithelial cells (LEC) and their subcellular structure were examined by bright-field microscopy, transmission electron microscopy (TEM) and scanning electron microscopy (SEM) 20, 40 and 60 days after the injection. Nitrogen oxide (NO) and nitric oxide synthase (NOS) were measured by biochemistry methods. Finally, inducible nitric oxide synthase (iNOS) protein and mRNA levels were monitored by Western blot and RT-PCR, respectively. Data was processed with two factorial experiment analysis of variance. RESULTS: Twenty to sixty days after the injection, marked or complete lens opacities appeared in the STZ group, whereas only slight opacities appeared in the lens in peritoneal and peribulbar puerarin groups and the lens in the control group remained clear. At the 20th, 40th and 60th day after the injection, optical microscope detected pathological changes of LEC in the STZ group. The cell volume was decreased with a dense nucleus and many bubbles appeared around the equator area. Under TEM, enlargement of cell gap, vacuoles in the cytoplasm, swelling of mitochondria and unclear structure of rough endoplasmic reticulum appeared in the LEC of the STZ group. Part of the nucleus was in karyopyknosis and peripheral nucleus gap was enlargement. Under SEM, normal fiber conjunction structure of the lens disappeared, fibers were swelling, part of fiber membranes were discontinuous, detached, and accumulated in certain areas. Mild lens opacities detected by bright-field microscope were developed in peritoneal and peribulbar puerarin injection groups. Nucleus and fibers in the lens cells of both groups appeared to be normal, with minor swelling of mitochondria, minor enlargement of endoplasmic reticulum and slight increase of intracellular space. NO, NOS and iNOS protein and mRNA of the lens were increased and up-regulated in STZ group. In the other two groups only minor changes were present and the changes were significantly less than that of the STZ group but greater than that in the control group. CONCLUSION: Peritoneal and peribulbar injection of puerarin have similar therapeutic effects in the treatment of rat diabetic cataract.


Assuntos
Catarata/patologia , Células Epiteliais/efeitos dos fármacos , Isoflavonas/farmacologia , Cristalino/efeitos dos fármacos , Animais , Catarata/etiologia , Catarata/metabolismo , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Células Epiteliais/metabolismo , Cristalino/citologia , Cristalino/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley
16.
J Hazard Mater ; 190(1-3): 945-51, 2011 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-21531507

RESUMO

The photocatalytic decolorization of methylene blue dye in aqueous solution using a novel photocatalyst MIL-53(Fe) metal-organic frameworks was investigated under UV-vis light and visible light irradiation. The effect of electron acceptor H(2)O(2), KBrO(3) and (NH(4))(2)S(2)O(8) addition on the photocatalytic performance of MIL-53(Fe) was also evaluated. The results show that MIL-53(Fe) photocatalyst exhibited photocatalytic activity for MB decolorization both under UV-vis light and visible light irradiation, and the MB decolorization over MIL-53(Fe) photocatalyst followed the first-order kinetics. The addition of different electron acceptors all enhances the photocatalytic performance of MIL-53(Fe) photocatalyst, and the enhanced rate follows the order of H(2)O(2)>(NH(4))(2)S(2)O(8)>KBrO(3) under UV-vis light irradiation, while in the order of (NH(4))(2)S(2)O(8)>H(2)O(2)>KBrO(3) under visible light irradiation. Moreover, MIL-53(Fe) did not exhibit any obvious loss of the activity for MB decolorization during five repeated usages. The photocatalytic activities over MIL-53(M) (M=Al, Fe), the isostructure to MIL-53(Fe), indicate that the metal centers show nil effect on the photocatalytic activity of MIL-53(M) photocatalysts.


Assuntos
Alumínio/química , Hidrocarbonetos Clorados/química , Ferro/química , Luz , Azul de Metileno/química , Fotólise , Catálise , Corantes/química , Corantes/efeitos da radiação , Cinética , Azul de Metileno/efeitos da radiação , Oxirredução , Soluções , Poluentes Químicos da Água/química , Poluentes Químicos da Água/efeitos da radiação
17.
Int J Ophthalmol ; 4(3): 250-4, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22553655

RESUMO

AIM: To evaluate the toxicity of endogeneous peroxynitrite on transplanted retinal pigment epithelial (RPE) sheets and the effect of puerarin on their survival in the C57BL/6 mice after RPE sheets have been transplanted into SD rats' subretinal space . METHODS: C57BL/6 mice eyes were used to culture RPE cells. Ninety-six SD rats were involved in the experiment. They were divided into control (block control), streptozotocin (STZ, negative control), untransplanted RPE (positive control) and transplanted RPE groups respectively. Diabetes was induced in SD rats by intra-peritoneal STZ injection in the latter three groups. Saline was injected into the subretinal space of 24 SD rats in the untransplanted RPE group and primary RPE sheets were injected into the subretinal space of 24 SD rats in the transplanted RPE group. Puerarin (45mg/kg) was administrated into both untransplanted RPE and transplanted RPE groups of diabetic rats through intra-peritoneal injection route after RPE sheets transplantation. At 20, 40, 60 days after surgery, Western blotting analysis, DNA ladder and RT-PCR were used for determining the differences in expression of nitrotyrosine (NT, the foot print of peroxynitrite ), apoptosis and iNOS mRNA in the control, STZ, untransplanted RPE and transplanted RPE groups respectively. HE staining was used for determining the RPE survival in the subretinal space of the transplanted RPE group. RESULTS: Apoptosis and expression of NT and iNOS mRNA were observed in STZ, untransplanted RPE and transplanted RPE groups, but were delayed in untransplanted RPE and transplanted RPE groups in a time-dependent manner compared with control and STZ groups (P<0.01). There were no differences between the two groups (P>0.01). NT, DNA ladder, iNOS mRNA were down-regulated, which were associated with the decrease of expression of peroxynitrite. Numerous pigmented cells emerged and increased in number in the subretinal space during the 60-day observation period after transplantation. On day 20, heavily pigmented cells were visible at the transplant site; On day 40, monolayer and multilayered transplant was visible in the subretinal space; On day 60, heavily pigmented monolayer and multilayered transplants with round apical profile were present along Bruch's membrane. CONCLUSION: Puerarin increased the 60-day survival of C57BL/6 mice RPE xenografts in the SD rats' subretinal space, which may be related to its direct inhibition of apoptosis of RPE cells and antagnism of damage of peroxynitrite to RPE cells.

18.
J Hazard Mater ; 186(2-3): 984-90, 2011 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-21159428

RESUMO

A novel type of magnetic porous carbonaceous polymeric material, CTF/Fe(2)O(3) composite (CTF = covalent triazine-based framework), has been synthesized by a facile microwave-enhanced high-temperature ionothermal method. By selecting ZnCl(2) as a reaction medium and the Lewis acid catalyst, and choosing FeCl(3)·6H(2)O as an iron oxide precursor, a series of CTF/Fe(2)O(3) composites with different γ-Fe(2)O(3) contents has been prepared in 60 min. The resulting samples were characterized by the X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), vibration sample magnetometer (VSM), and N(2) sorption-desorption isotherms. The obtained CTF/Fe(2)O(3) composites exhibit high surface areas (930-1149 m(2) g(-1)), and their saturation magnetizations at 300 K vary from 1.1 to 5.9 emu g(-1), depending respectively on different Fe(2)O(3) contents (6.43-12.43 wt%) in the CTF/Fe(2)O(3) composites. The CTF/Fe(2)O(3) composites were applied to remove organic dye from aqueous solution by selecting methyl orange as a model molecule, and both high adsorption capacity (291 mg g(-1), corresponding to 0.889 mmol g(-1)) and fast adsorption kinetics (k(ads) = 4.31 m(2) mg(-1) min(-1)) were observed.


Assuntos
Corantes/química , Compostos Orgânicos/química , Triazinas/química , Adsorção , Algoritmos , Compostos Azo/química , Cloretos/química , Compostos Férricos/química , Temperatura Alta , Indicadores e Reagentes , Cinética , Magnetismo , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Micro-Ondas , Espectroscopia Fotoeletrônica , Porosidade , Soluções , Espectrofotometria Infravermelho , Termodinâmica , Água , Difração de Raios X , Compostos de Zinco/química
19.
Colloids Surf B Biointerfaces ; 78(2): 229-36, 2010 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-20399625

RESUMO

In this paper, we report a biogenic synthesis protocol for preparation of calcium oxalate (CaC2O4, CaOx) crystal at room temperature by a simple protein-mediated reaction of aqueous Ca2+ ions with the C2O4(2-) ions spontaneously released from spinach. The aggregation of calcium oxalate monohydrate (COM) and calcium oxalate dihydrate (COD) with a rod-like morphology was mainly formed in the spinach root lixivium, and the proportion of COM crystal in the aggregation increased with the concentration of Ca2+ ions increasing, however, spindle-shaped crystal was mainly obtained in the spinach leaf lixivium and the content of COM in the product was higher than that obtained in the root lixivium with the similar concentration of Ca2+ ions. COM phase disappeared and only COD crystal with morphology of tetragonal bipyramidal prisms presented in the product when the leaf lixivium was replaced by the leaf broth. The biomolecules such as proteins with molecular weight of 31kDa liberated from the spinach root are negative-charged, which played important roles for the control of CaOx crystal growth in the root lixivium corresponding to the changes of protein secondary structures after reaction with Ca2+ ions. This research was potentially important for unraveling the biomineralization mechanism of CaOx crystal.


Assuntos
Oxalato de Cálcio/química , Cálcio/química , Spinacia oleracea/química , Cálcio/metabolismo , Oxalato de Cálcio/metabolismo , Cristalização , Eletroforese em Gel de Poliacrilamida , Íons/química , Íons/metabolismo , Microscopia Eletrônica , Peso Molecular , Tamanho da Partícula , Folhas de Planta/química , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Raízes de Plantas/química , Raízes de Plantas/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Spinacia oleracea/metabolismo , Difração de Raios X
20.
Int J Ophthalmol ; 3(4): 283-7, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-22553574

RESUMO

AIM: To evaluate the peroxynitrite (ONOO(-)) of puerarin on retinal pigment epithelial (RPE) cells apoptosis induced partly by peroxynitrite via Fas/FasL. METHODS: RPE cells from C57BL/6 mice eyes were cultured. Diabetes was induced in Sprague-Dawley (SD) rats by streptozotocin (STZ) intraperitoneal injection. Puerarin was administrated to cultured RPE cells and diabetic rats. Western blotting analysis, DNA ladder, RT-PCR, immunohistochemistry were used for determining the expression of nitrotyrosine (NT, the foot print of ONOO(-)), complement 3 (C3); apoptosis and inducible nitric oxide synthase (iNOS) mRNA as well as Fas/FasL signal transduction in RPE cells. RESULTS: Both RPE cells in ONOO(-) and puerarin group developed apoptosis and expressed NT, C3, iNOS mRNA and Fas/FasL. But latter delayed the all changes in a time-dependent manner compared with control and STZ group (P<0.001). iNOS, C3 and Fas/FasL were up-regulated and associated with an increase of expression of ONOO(-)in vivo and in vitro. CONCLUSION: Puerarin decreases RPE cells apoptosis partly induced by ONOO(-) for diabetic retinopathy.

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