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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.
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Prolapso de Órgano Pélvico , Incontinencia Urinaria de Esfuerzo , Incontinencia Urinaria , Humanos , Femenino , Estudios de Seguimiento , Resultado del Tratamiento , Polipropilenos , Estudios Retrospectivos , Calidad de Vida , Mallas Quirúrgicas , Prolapso de Órgano Pélvico/cirugía , Incontinencia Urinaria/cirugía , Encuestas y CuestionariosRESUMEN
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.
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Cabestrillo Suburetral , Incontinencia Urinaria de Esfuerzo , Femenino , Humanos , Calidad de Vida , Estudios Retrospectivos , Cabestrillo Suburetral/efectos adversos , Incontinencia Urinaria de Esfuerzo/cirugía , UrodinámicaRESUMEN
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.
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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.
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Catarata/patología , Células Epiteliales/efectos de los fármacos , Isoflavonas/farmacología , Cristalino/efectos de los fármacos , Animales , Catarata/etiología , Catarata/metabolismo , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patología , Células Epiteliales/metabolismo , Cristalino/citología , Cristalino/metabolismo , Masculino , Ratas , Ratas Sprague-DawleyRESUMEN
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.
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Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Doxorrubicina/farmacología , Grafito/química , Nanopartículas Magnéticas de Óxido de Hierro/química , Nanocompuestos/química , Neoplasias/tratamiento farmacológico , Compuestos de Nitrógeno/química , Polímeros/química , Pirroles/química , Protocolos de Quimioterapia Combinada Antineoplásica/química , Supervivencia Celular/efectos de los fármacos , Doxorrubicina/química , Células Hep G2 , Humanos , Hipertermia Inducida/métodos , Hipoxia/metabolismo , Neoplasias/metabolismo , Fotoquimioterapia/métodos , Fármacos Fotosensibilizantes/química , Fototerapia/métodosRESUMEN
Two lipophilic ligands containing triazole and hydroxyl groups, N-alkyl(C(n)H(2n+1))-3,5-bis(hydroxymethyl)-1,2,4-triazole (n=10 and 12), were synthesized. Effects of their Cu(II) and Ni(II) complexes on the hydrolysis of p-nitrophenyl picolinate (PNPP) in cetyltrimethylammonium bromide (CTAB) micelles have been investigated kinetically, and some kinetic parameters of the reactions were obtained by employing the ternary complex kinetic model for metallomicellar catalysis. It was found that Cu(II) complexes of these triazole-based ligands showed more effective catalytic activity on the hydrolysis of PNPP than Ni(II) complexes. Also, the apparent first-order rate constants for product formation in the metallomicellar phase (k(N)(')), the association constants between the substrate and the binary complex (K(T)), and the association constants between the metal ion and the ligand (K(M)) increased with an increase in pH value, which may be attributed to an increase in the nucleophilicity of the hydroxyl groups in the ligand or the electrophilicity of the substrate at higher pH. In addition, at constant pH, k(N)(') and K(T) increased with an increase in the hydrocarbon chain length of the ligand, while K(M) decreased.
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Compuestos de Cetrimonio/química , Nitrofenoles/química , Compuestos Organometálicos/química , Ácidos Picolínicos/química , Triazoles/química , Catálisis , Cetrimonio , Cobre/química , Concentración de Iones de Hidrógeno , Hidrólisis , Ligandos , Micelas , Níquel/química , Compuestos Organometálicos/síntesis química , Propiedades de SuperficieRESUMEN
The patient bile and its centrifugate were studied by FTIR spectra, UV-Vis spectra, particle size analysis, and zeta potential determination. The result showed that the patient bile was in a heterogenetic and unstable state, and some of the ultramicrons in the patient bile assembled to form precipitate after centrifugalized at different speeds. According to FTIR and UV-Vis spectra, the authors found that the composition of the precipitates was mainly cholesterol, bilirubin, calcium bilirubinate, protein, phospholipid and so on, which was much close to that of the core of patient gallstone. The change in the properties of cholesterol/phospholipid vesicles, and the production of the undissolvable calcium salt in the patient bile had crucial influence on the stability of the patient bile, which played important roles in the core-formation and initial growth of gallstone that were induced by the matrixes such as proteins, phospholipids etc.
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Bilis/química , Humanos , Tamaño de la Partícula , Espectrofotometría , Espectrofotometría Infrarroja , Espectroscopía Infrarroja por Transformada de FourierRESUMEN
By means of artificial neural network and Levenberg Marquardt Back Propagation (LM-BP) train algorithm, the three components of pyrocatechol, resorcinol and hydroquinone were determined simultaneously. The absorption spectra of these three components severely overlap in ultraviolet spectral range. Three wavelengths at 283.5, 279.5 and 276.5 nm were selected for the determination. 25 mixture standard solutions were prepared according to orthogonal projection form L25 (5(6)). Three kinds of components were trained. Mean Squared Error (MSE) reaching minimum value is 0.083 114 3. Meanwhile the contents of pyrocatechol, resorcinol and hydroquinone in six simulation mixture samples were predicted. The relative errors of the three kinds of components were slightly larger under the low concentration condition, and the mean relative error for most analytical results was less than 5%, especially it is satisfactory for the analytical results of pyrocatechol and resorcinol with severely overlapped absorption spectra.
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OBJECTIVE: To explore the mechanism of Sanqi Qiancao Recipe (SQR) in treating metrorrhagia caused by copper intrauterine device (IUD) in rabbits and to provide experimental evidence for preventing and treating this disease. METHODS: Fifty-six rabbits were randomly divided into seven groups, which were normal control group, sham-operation group, untreated group, indomethacin-treated group, low-dose SQR-treated group, medium-dose SQR-treated group and high-dose SQR-treated group. Copper IUD insertion was operated in rabbits of the last five groups. Rabbits in the last four groups were treated orally with indomethacin and low-, medium- and high-dose SQR respectively for a week. Rabbits in the untreated group, normal control group and sham-operation group were given distilled water orally. Hematocrit, blood viscosity at low, medium and high shear rate, plasma viscosity and blood sedimentation were examined after treatment. RESULTS: The hematocrit, blood viscosity at low, medium and high shear rate and plasma viscosity were higher in the untreated group than those in the normal control group with significant differences (P<0.01) while those indexes in low-, medium- and high-dose SQR-treated groups were significantly lower than those in the untreated group (P<0.05 or P<0.01). CONCLUSION: SQR can lead to a decrease in blood viscosity and improve the blood flow, which may be one of the mechanisms of SQR in treating metrorrhagia after copper IUD insertion.
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Medicamentos Herbarios Chinos/uso terapéutico , Hemorreología/efectos de los fármacos , Dispositivos Intrauterinos de Cobre/efectos adversos , Fitoterapia , Hemorragia Uterina/prevención & control , Animales , Medicamentos Herbarios Chinos/farmacología , Femenino , Conejos , Distribución Aleatoria , Hemorragia Uterina/etiologíaRESUMEN
Interactions between a cationic gemini surfactant, 1,2-ethane bis(dimethyldodecylammonium bromide) (designated as 12-2-12), and a nonionic polymer polyvinyl alcohol (PVA) were investigated by means of viscosity and specific conductance. Results show that PVA displays special viscosity behavior in aqueous solutions containing the gemini surfactant 12-2-12, which is due to the molecular interaction of the polymer and the surfactant. It was found that the special viscosity depended on ionization of the surfactant, as well as polymer concentration and surfactant concentration in the nonionic polymer-surfactant system. A theoretical expression for the dependence of the solution viscosity on the ionization of the surfactant micelle was given, and the new equation proved to be in good agreement with the experimental data.
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N,N-dimethylferrocenylmethylhexadecylammonium bromide (FC16AB) was synthesized and characterized by the spectra of UV-Visible, FTIR 1H NMR, ESMS, etc. Surface tensions of different concentrations of FC16AB water solution were measured, which shows that FC16AB has good surface activity. The surface pressure-area (pi-A) curves and differentiated pi-A curves of FC16AB on water, Cl-, and SO(4)2- subphases were studied. The results indicate that FC16AB molecules can form the most stable monolayer on the subphase containing Cl-.
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4-methyl-5-hydroxy-ethyl isothiazole stearic ester (HISE) was synthesized and characterized by FTIR spectroscopy, 1H NMR and MS. The monolayer-forming ability of HISE was studied in subphases with different pH values using isotherms of surface pressure-area per molecule (pi-A). It was observed that the collapse pressure and the film-forming ability of the monolayers of HISE increased gradually as pH values ascended. Research of differentiated pi-A curves (d pi(/dA-A) indicated that there were one or two phase change points during the compressing process, and the incompressibility and the stability of HISE monolayers on alkalescent subphases were better than on acid subphases.
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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.
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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.
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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.
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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, Pâ=â.003) and the use of parenteral antibiotics (aOR 5.55, 95% aCI 1.21-24.73, Pâ=â.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.
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Infecciones por Caliciviridae/diagnóstico , Infecciones por Caliciviridae/epidemiología , Técnicas de Laboratorio Clínico/métodos , Gastroenteritis/diagnóstico , Norovirus/enzimología , ARN Polimerasa Dependiente del ARN/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Secuencia de Bases , Infecciones por Caliciviridae/virología , Preescolar , Demografía , Electroforesis en Gel de Agar , Reacciones Falso Positivas , Femenino , Gastroenteritis/epidemiología , Gastroenteritis/virología , Humanos , Incidencia , Modelos Logísticos , Masculino , Norovirus/genética , Filogenia , Factores de RiesgoRESUMEN
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.
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Flammulina/genética , Proteínas Fúngicas/biosíntesis , Pichia/genética , Proteínas Recombinantes/biosíntesis , Animales , Eritrocitos/efectos de los fármacos , Flammulina/crecimiento & desarrollo , Proteínas Fúngicas/genética , Proteínas Fúngicas/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Interferón gamma/metabolismo , Interleucina-2/metabolismo , Linfocitos/efectos de los fármacos , Linfocitos/metabolismo , Ratones , Proteínas Recombinantes/genética , Proteínas Recombinantes/farmacologíaRESUMEN
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).
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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.
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Sustancias Explosivas/análisis , Microondas , Nanopartículas , Triazinas/química , Fluorescencia , Límite de Detección , Microscopía Electrónica de Transmisión , Espectrometría de Fluorescencia , Espectrofotometría InfrarrojaRESUMEN
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.