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1.
Sci Rep ; 13(1): 18435, 2023 10 27.
Artículo en Inglés | MEDLINE | ID: mdl-37891374

RESUMEN

Spermatogenesis is a complex process related to male infertility. Till now, the critical genes and specific mechanisms have not been elucidated clearly. Our objective was to determine the hub genes that play a crucial role in spermatogenesis by analyzing the differentially expressed genes (DEGs) present in non-obstructive azoospermia (NOA) compared to OA and normal samples using bioinformatics analysis. Four datasets, namely GSE45885, GSE45887, GSE9210 and GSE145467 were used. Functional enrichment analyses were performed on the DEGs. Hub genes were identified based on protein-protein interactions between DEGs. The expression of the hub genes was further examined in the testicular germ cell tumors from the TCGA by the GEPIA and validated by qRT-PCR in the testes of lipopolysaccharide-induced acute orchitis mice with impaired spermatogenesis. A total of 203 DEGs including 34 up-regulated and 169 down-regulated were identified. Functional enrichment analysis showed DEGs were mainly involved in microtubule motility, the process of cell growth and protein transport. PRM2, TEKT2, FSCN3, UBQLN3, SPATS1 and GTSF1L were identified and validated as hub genes for spermatogenesis. Three of them (PRM2, FSCN3 and TEKT2) were significantly down-regulated in the testicular germ cell tumors and their methylation levels were associated with the pathogenesis. In summary, the hub genes identified may be related to spermatogenesis and may act as potential therapeutic targets for NOA and testicular germ cell tumors.


Asunto(s)
Infertilidad Masculina , Neoplasias de Células Germinales y Embrionarias , Humanos , Masculino , Animales , Ratones , Perfilación de la Expresión Génica , Espermatogénesis/genética , Testículo/metabolismo , Infertilidad Masculina/patología , Biología Computacional , Neoplasias de Células Germinales y Embrionarias/patología
2.
Biol Pharm Bull ; 45(11): 1616-1626, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36328497

RESUMEN

The dysregulation of certain long non-coding RNAs (lncRNAs) has been considered to be involved in neuropsychiatric disorders such as depression, implying the vital role of these transcripts. We have previously identified many differentially expressed lncRNAs in chronic unpredictable mild stress (CUMS) induced mice. Among them, lncRNA Gm16638-201 was highly expressed in the hippocampus (HIP) of CUMS, but the specific role and the underlying mechanisms remain unclear. Here, we reported that lncRNA Gm16638-201 was highly expressed in the prefrontal cortex (PFC) of CUMS induced depressive mice. Bioinformatic analysis shows that Gm16638-201 is mainly located in the cytoplasm. Nine neurological-related genes (Elmo2, Satb1, Hnrnpul1, Sipa1l3, Mapt, Tada3, Sgip1, IL-16, and StarD5) were predicted to be regulated in cis or trans by Gm16638-201 and involved into the 14-3-3Ɛ neurotrophic signaling pathway. We further confirmed the down-regulation of 14-3-3Ɛ and the nine predicted target genes in the PFC of CUMS mice except for Sgip1 and IL-16. In addition, they were also down-regulated in the primary cortical cell cultures with overexpression of Gm16638-201 constructed using an adenoviral-medicated gene expression system. In conclusion, we found that overexpression of Gm16638-201 negatively regulated several target genes and inhibited the 14-3-3Ɛ pathway in the PFC of CUMS induced depressive mice. This promising result suggests that Gm16638-201 may be a potential novel therapeutic target for depression.


Asunto(s)
Antidepresivos , ARN Largo no Codificante , Ratones , Animales , Antidepresivos/uso terapéutico , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Depresión/tratamiento farmacológico , Estrés Psicológico/metabolismo , Interleucina-16/metabolismo , Modelos Animales de Enfermedad , Corteza Prefrontal/metabolismo , Hipocampo/metabolismo , Proteínas del Citoesqueleto/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Factores de Transcripción/metabolismo
3.
Zool Res ; 42(1): 28-42, 2021 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-33420763

RESUMEN

Depression is a prevalent mental disorder that is associated with aging and contributes to increased mortality and morbidity. The overall prevalence of geriatric depression with clinically significant symptoms is currently on the rise. Recent studies have demonstrated that altered expressions of long non-coding RNAs (lncRNAs) in the brain affect neurodevelopment and manifest modulating functions during the depression. However, most lncRNAs have not yet been studied. Herein, we analyzed the transcriptome of dysregulated lncRNAs to reveal their expressions in a mouse model exhibiting depressive-like behaviors, as well as their corresponding response following antidepressant fluoxetine treatment. A chronic unpredictable mild stress (CUMS) mouse model was applied. A six-week fluoxetine intervention in CUMS-induced mice attenuated depressive-like behaviors. In addition, differential expression analysis of lncRNAs was performed following RNA-sequencing. A total of 282 lncRNAs (134 up-regulated and 148 down-regulated) were differentially expressed in CUMS-induced mice relative to non-stressed counterparts ( P<0.05). Moreover, 370 differentially expressed lncRNAs were identified in CUMS-induced mice after fluoxetine intervention. Gene Ontology (GO) analyses showed an association between significantly dysregulated lncRNAs and protein binding, oxygen binding, and transport activity, while the Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis indicated that these dysregulated lncRNAs might be involved in inflammatory response pathways. Fluoxetine effectively ameliorated the symptoms of depression in CUMS-induced mice by regulating the expression of lncRNAs in the hippocampus. The findings herein provide valuable insights into the potential mechanism underlying depression in elderly people.


Asunto(s)
Trastorno Depresivo/tratamiento farmacológico , Fluoxetina/uso terapéutico , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , ARN Largo no Codificante/metabolismo , Animales , Antidepresivos de Segunda Generación/uso terapéutico , Masculino , Ratones , Ratones Endogámicos BALB C , ARN Largo no Codificante/genética , Estrés Psicológico
4.
Mol Plant ; 13(12): 1802-1815, 2020 12 07.
Artículo en Inglés | MEDLINE | ID: mdl-33075506

RESUMEN

Several photorespiratory bypasses have been introduced into plants and shown to improve photosynthesis by increasing chloroplastic CO2 concentrations or optimizing energy balance. We recently reported that an engineered GOC bypass could increase photosynthesis and productivity in rice. However, the grain yield of GOC plants was unstable, fluctuating in different cultivation seasons because of varying seed setting rates. In this study, we designed a synthetic photorespiratory shortcut (the GCGT bypass) consisting of genes encoding Oryza sativa glycolate oxidase and Escherichia coli catalase, glyoxylate carboligase, and tartronic semialdehyde reductase. The GCGT bypass was guided by an optimized chloroplast transit peptide that targeted rice chloroplasts and redirected 75% of carbon from glycolate metabolism to the Calvin cycle, identical to the native photorespiration pathway. GCGT transgenic plants exhibited significantly increased biomass production and grain yield, which were mainly attributed to enhanced photosynthesis due to increased chloroplastic CO2 concentrations. Despite the increases in biomass production and grain yield, GCGT transgenic plants showed a reduced seed setting rate, a phenotype previously reported for the GOC plants. Integrative transcriptomic, physiological, and biochemical assays revealed that photosynthetic carbohydrates were not transported to grains in an efficient manner, thereby reducing the seed setting rate. Taken together, our results demonstrate that the GCGT photorespiratory shortcut confers higher yield by promoting photosynthesis in rice, mainly through increasing chloroplastic CO2 concentrations.


Asunto(s)
Biomasa , Luz , Oryza/crecimiento & desarrollo , Oryza/efectos de la radiación , Fotosíntesis/efectos de la radiación , Semillas/crecimiento & desarrollo , Transporte Biológico/efectos de la radiación , Metabolismo de los Hidratos de Carbono/efectos de la radiación , Dióxido de Carbono/metabolismo , Respiración de la Célula/efectos de la radiación , Cloroplastos/metabolismo , Cloroplastos/efectos de la radiación , Cloroplastos/ultraestructura , Regulación de la Expresión Génica de las Plantas/efectos de la radiación , Metaboloma/efectos de la radiación , Oryza/genética , Hojas de la Planta/metabolismo , Hojas de la Planta/efectos de la radiación , Hojas de la Planta/ultraestructura , Plantas Modificadas Genéticamente , Semillas/efectos de la radiación , Transcriptoma/genética
6.
ACS Appl Mater Interfaces ; 11(33): 29934-29940, 2019 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-31329412

RESUMEN

Constructing advanced anode materials with suitable operational potential and high energy density toward metal ion batteries is of significance for next-generation batteries. Carbon-coated porous Sb2Te3 nanoplates with high density and suitable operational potential, prepared by a hydrothermal and carbonization technique, manifest good electrochemical performance, including excellent rate capability, high capacities, and outstanding cycling performance. This performance can be traced to its special structure, including porous Sb2Te3 and the shell of carbon, which can provide fast charge transfer paths and maintain the structural stability for the entire material. The proposed strategy here of embedding porous high-density anode material in two-dimensional carbon provides a new avenue for designing anode materials with excellent gravimetric and volumetric capacities toward superior energy storage.

7.
Environ Pollut ; 252(Pt B): 1539-1549, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31277023

RESUMEN

Silver nanoparticles (AgNPs) have adverse impacts on plants when released into environments, but their toxic mechanism is still a matter of debate. Here we present a combined analysis of physiology and transcriptome of Arabidopsis thaliana leaves exposure to 30 mg L-1 AgNPs and Ag+ for six days to explore the toxicity mechanism of AgNPs on Arabidopsis. Both transcriptomic and physiological results showed that AgNPs induced reactive oxygen species (ROS) accumulation and damaged photosynthesis. The toxicity of AgNPs is not merely attributable to Ag+ release and much higher photosynthetic toxicity and ROS accumulation were observed in 30 mg L-1 AgNPs than that in 0.12 mg L-1 Ag+. About 60% genes were similarly up- or down-regulated at the same concentration of AgNPs and Ag+ and these genes were enriched in photosynthesis and response to the stimulus. However, 302 genes, including those involved in glucosinolates synthesis, were specifically regulated under AgNPs treatments. In conclusion, more than the released Ag+, nanoparticle-specific effects are responsible for the toxicity of AgNPs in Arabidopsis thaliana.


Asunto(s)
Arabidopsis/efectos de los fármacos , Nanopartículas del Metal/toxicidad , Fotosíntesis/efectos de los fármacos , Plata/toxicidad , Transcriptoma/efectos de los fármacos , Arabidopsis/genética , Arabidopsis/metabolismo , Fotosíntesis/genética , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/metabolismo , Especies Reactivas de Oxígeno/metabolismo
8.
ACS Appl Mater Interfaces ; 9(29): 24857-24863, 2017 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-28635250

RESUMEN

To achieve both fast response and structural integrity during the repeating volume changes are the most significant challenges for thermoresponsive hydrogels. In this work, AuNRs/PNIPAM composite hydrogel with fast thermal/optical response and structural integrity is facilely prepared by electrospinning and following a curing treatment. By combining the photothermal property of AuNRs and thermal-responsive effect of PNIPAM, the composite hydrogel shows fast thermal/photoresponse, high heating rate, and high structural integrity with fierce size change. When laser irradiation begins, the temperature of the film increases from room temperature to 34.5 °C in 1 s and will further increase even to 60 °C in 5 s. Both the porous structure of the hydrogel and the assemble effect of AuNRs within the PNIPAM fibers facilitate the fast responsibility. Furthermore, to take advantage of this fibrous hydrogel adequately, one novel kind of thermal/photocontrolled switch based on the composite hydrogel is prepared, which exhibits fast responsivity and high stability even under acidic or basic conditions.

9.
ChemSusChem ; 9(12): 1449-54, 2016 06 22.
Artículo en Inglés | MEDLINE | ID: mdl-27214754

RESUMEN

In this work, we demonstrate an electrospinning technique to fabricate TiO2 /upconversion nanoparticles (UCNPs)/CdS nanofibers on large scale. In addition, the as-prepared TiO2 nanofibers are incorporated with a high population of UCNPs and CdS nanospheres; this results in Förster resonance energy-transfer configurations of the UCNPs, TiO2 , and CdS nanospheres that are in close proximity. Hence, strong fluorescent emissions for the Tm(3+) ions including the (1) G4 →(3) H6 transition are efficiently transferred to TiO2 and the CdS nanoparticles through an energy-transfer process. The as-prepared TiO2 /UCNPs/CdS nanofibers exhibit full-spectrum solar-energy absorption and enable the efficient degradation of organic dyes by fluorescence resonance energy transfer between the UCNPs and TiO2 (or CdS). The UCNPs/TiO2 /CdS nanofibers may also have enhanced energy-transfer efficiency for wide applications in solar cells, bioimaging, photodynamics, and chemotherapy.


Asunto(s)
Absorción Fisicoquímica , Compuestos de Cadmio/química , Nanofibras/química , Nanopartículas/química , Procesos Fotoquímicos , Sulfuros/química , Luz Solar , Titanio/química , Catálisis , Rayos Infrarrojos
10.
Chempluschem ; 81(11): 1147-1151, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31964100

RESUMEN

A plasmonic biosensor for arsenate has been developed which uses gold nanoparticles (AuNPs) as the signal reporter and in which the biocatalytic activity of acid phosphatase (AcP) is modified by the target ion. The enzyme catalyzes the hydrolysis of negatively charged adenosine 5'-monophosphate (AMP) to neutral adenosine, causing appreciable aggregation of AuNPs and then visible color change of the solution from red to blue. The presence of arsenate (AsV ), as a molecular analogue of phosphate, can effectively interfere with the bioactivity of AcP by competitive inhibition, and so the hydrolysis process is slowed down. This is reflected by the change in the solution color from blue to red with increasing concentrations of AsV . In contrast to AuNP-based sensors for arsenic (basically AsIII ) that employ the strong interaction between AsIII -specific molecules and AsIII , this sensor adopts a different sensing principle and is the first visible sensor for specifically AsV specifically using AuNPs. Finally the practical assay of AsV in groundwater and lake water was performed with satisfactory results, suggesting this approach can be used for quantification of AsV levels in real water samples.

11.
Med Sci Monit ; 21: 3616-21, 2015 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-26591002

RESUMEN

BACKGROUND: The aim of this work was to study the Fabp4 and Pten gene expression and correlation in the liver, muscle, and adipose tissues of type 2 diabetes mellitus (T2DM) rats. MATERIAL AND METHODS: Male Wistar rats (8 weeks old) were randomly divided into 2 groups (n=12/group): a control group fed a normal diet for 8 weeks and an experimental group fed a high-fat, high-sugar diet for 8 weeks and that received 25 mg/kg streptozotocin by intraperitoneal injection to induce T2DM. The random blood glucose, fasting blood glucose, and fasting insulin levels were measured. The expression of Pten and Fabp4 in the liver, muscle, and epididymal adipose tissues was estimated by real-time quantitative PCR. Pearson correlation coefficient analysis was used to investigate the expression correlation between Pten and Fabp4 in T2DM rats. RESULTS: The gene expressions of Pten and Fabp4 in the liver, muscle, and adipose tissues of T2DM rats were all significantly higher than those in the control group (P<0.05). Pten was highly expressed in the muscles and Fabp4 was highly expressed in muscle and adipose tissues. Furthermore, expressions of Fabp4 and Pten in the muscle and adipose tissues of T2DM rats were positively correlated (P<0.05), but not in the liver. CONCLUSIONS: The increased expression of PTEN and FABP4 in the adipose and muscles of T2DM rats may play an important role in the insulin resistance of T2DM. However, the mechanism by which these 2 genes function in T2DM needs further study.


Asunto(s)
Diabetes Mellitus Tipo 2/genética , Proteínas de Unión a Ácidos Grasos/genética , Fosfohidrolasa PTEN/genética , Tejido Adiposo/metabolismo , Adiposidad , Animales , Glucemia/metabolismo , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Proteínas de Unión a Ácidos Grasos/metabolismo , Perfilación de la Expresión Génica , Insulina/sangre , Insulina/metabolismo , Resistencia a la Insulina , Hígado/metabolismo , Masculino , Músculos/metabolismo , Obesidad/metabolismo , Fosfohidrolasa PTEN/metabolismo , Ratas , Ratas Wistar
12.
BMC Infect Dis ; 14: 260, 2014 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-24886028

RESUMEN

BACKGROUND: Shigellae have become increasingly resistant to the extended-spectrum cephalosporin (ESC) worldwide and pose a great challenge to anti-infection treatment options. The purpose of this study was to determine the resistance, cephalosporin resistance mechanisms, virulence characteristic and genotype of ESC-resistant Shigella. METHODS: From 2008 to 2012, Shigella isolates collected from diarrhea patients were detected for antibiotics sensitivity by disk diffusion, cephalosporin resistance determinants and virulence genes using polymerase chain reaction (PCR) and genotyping through enterobacterial repetitive intergenic consensus sequence PCR (ERIC-PCR). RESULTS: A total of 356 Shigella isolates were gathered, and 198 (55.6%, 58 S. flexneri and 140 S. sonnei) were resistant to ESC. All ESC-resistant isolates were susceptible to imipenem, and only 0.5% isolate was resistant to piperacillin/tazobactam. ESC-resistant S. flexneri showed high degrees of resistance to ampicillin (100%), ampicillin/sulbactam (96.6%), piperacillin (100%), trimethoprim/sulfamethoxazole (74.1%), ciprofloxacin (74.1%), levofloxacin (53.4%), ceftazidime (58.6%) and cefepime (58.6%). ESC-resistant S. sonnei exhibited high resistance rates to ampicillin (100%), piperacillin (100%) and trimethoprim/sulfamethoxazole (96.4%). Cephalosporin resistance genes were confirmed in 184 ESC-resistant isolates. bla(CTX-M) types (91.8%, mainly bla(CTX-M-14), bla(CTX-M-15) and bla(CTX-M-57)) were most prevalent, followed by bla(OXA-30) (26.3%). Over 99.0% ESC-resistant isolates harbored virulence genes ial, ipaH, virA and sen. However, set1 were more prevalent in ESC-resistant S. flexneri isolates than in S. sonnei isolates. ERIC-PCR results showed that 2 and 3 main genotypes were detected in ESC-resistant S. flexneri and S. sonnei, respectively. CONCLUSION: Our findings indicated that a high prevalence of ESC-resistant Shigella mediated mainly by bla(CTX-M) with stronger resistance and virulence, and the existence of specific clones responsible for these Shigella infection in the region studied.


Asunto(s)
Resistencia a las Cefalosporinas/genética , Disentería Bacilar/microbiología , Shigella/genética , Adolescente , Adulto , Antibacterianos , Cefepima , Cefalosporinas , Niño , Preescolar , China , Ciprofloxacina , Femenino , Galanina/análogos & derivados , Genes Bacterianos , Genotipo , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Ácido Penicilánico/análogos & derivados , Piperacilina , Combinación Piperacilina y Tazobactam , Reacción en Cadena de la Polimerasa , Shigella/patogenicidad , Sustancia P/análogos & derivados , Virulencia , beta-Lactamasas/genética
13.
Chem Soc Rev ; 43(13): 4423-48, 2014 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-24695773

RESUMEN

Nanofibres can be fabricated by various methods and perhaps electrospinning is the most facile route. In past years, electrospinning has been used as a synthesis technique and the fibres have been prepared from a variety of starting materials and show various properties. Recently, incorporating functional nanoparticles (NPs) with electrospun fibres has emerged as one of most exciting research topics in the field of electrospinning. When NPs are incorporated, on the one hand the NPs endow the electrospun fibres/mats novel or better performance, on the other hand the electrospun fibres/mats could preserve the NPs from corrosion and/or oxidation, especially for NPs with anisotropic structures. More importantly, electrospinning shows potential applications in self-assembly of nanoscale building blocks for generating new functions, and has some obvious advantages that are not available by other self-assembly methods, i.e., the obtained free-standing hybrid mats are usually flexible and with large area, which is favourable for their commercial applications. In this critical review, we will focus on the fabrication and applications of NPs-electrospun fibre composites and give an overview on this emerging field combining nanoparticles and electrospinning. Firstly, two main strategies for producing NPs-electrospun fibres will be discussed, i.e., one is preparing the NPs-electrospun fibres after electrospinning process that is usually combined with other post-processing methods, and the other is fabricating the composite nanofibres during the electrospinning process. In particular, the NPs in the latter method will be classified and introduced to show the assembling effect of electrospinning on NPs with different anisotropic structures. The subsequent section describes the applications of these NPs-electrospun fibre mats and nanocomposites, and finally a conclusion and perspectives of the future research in this emerging field is given.

14.
Nanoscale ; 5(10): 4223-9, 2013 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-23538908

RESUMEN

In this paper, we report the fabrication of co-assembled thin films composed of silver nanowires (NWs) and Au nanoparticles (NPs) at the liquid-liquid interface (water-chloroform) by vigorous shaking. The composition of co-assembled thin films can be controlled by adjusting the concentration of the nanosized building blocks. As a versatile interfacial assembly method, other nanoparticles such as Ag2S and Fe3O4 NPs can also be co-assembled with Ag NWs using the same procedure. Meanwhile, the co-assembly state of the obtained Au NPs and Ag NWs makes a significant contribution to the high sensitivity of surface-enhanced Raman scattering (SERS) to model the molecule 3,3'-diethylthiatricarbocyanine iodide (DTTCI). The SERS intensities show high dependence on the molar ratio of Au NPs and Ag NWs and the layer number of the co-assembled thin films. This shaking-assisted liquid-liquid assembly system has been proved to be a facile way for co-assembling nanowires and nanoparticles, and will pave a way for further applications of the macroscopic co-assemblies with novel functionalities.

16.
Nanoscale ; 4(17): 5348-55, 2012 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-22678030

RESUMEN

Gold nanorods (AuNRs) can be successfully co-assembled with Ag nanowires (AgNWs) to form a kind of AuNR-AgNW nanocomposite by electrostatic attraction, in which the AuNRs are arranged along the long axial direction of the AgNWs with a preferential string-like alignment. The assembled AuNR-AgNW nanocomposites are then further embedded within polyvinyl alcohol (PVA) nanofibers by electrospinning, by which both AuNRs and AgNWs can be stabilized and arranged along the axis of polymer nanofibers. When the polymer nanofibers are aligned by collecting on a copper mesh with a woven structure, the AuNR-AgNW nanocomposites assembled within the electrospun nanofibers are also arranged. The influences of the AuNR-AgNW assemblies with different amounts of AuNRs attached on AgNWs on the optical properties and surface enhanced Raman scattering (SERS) enhancement have been investigated. The resulting AuNR-AgNW/PVA electrospun mats show red-shifted and broader absorption bands and higher SERS performances compared with the normal casting films with randomly dispersed AuNRs and AgNWs, or electrospun mats with monometallic components, due to the order alignment of AuNR-AgNW nanocomposites on a large scale.


Asunto(s)
Oro/química , Nanofibras/química , Nanotubos/química , Nanocables/química , Alcohol Polivinílico/química , Plata/química , Nanofibras/ultraestructura , Nanotubos/ultraestructura , Polímeros/química , Espectrometría Raman
17.
ACS Nano ; 6(5): 4500-7, 2012 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-22530775

RESUMEN

We report a unique approach for the fabrication of a family of curling tubular nanostructures rapidly created by a rolling up of carbon membranes under in situ TEM electron beam irradiation. Multiwall tubes can also be created if irradiation by electron beam is performed long enough. This general approach can be extended to curve the conductive carbon film loaded with various functional nanomaterials, such as nanocrystals, nanorods, nanowires, and nanosheets, providing a unique strategy to make composite tubular structures and composite materials by a combination of desired optical, electronic, and magnetic properties, which could find potential applications, including fluid transportation, encapsulation, and capillarity on the nanometer scale.

18.
ACS Appl Mater Interfaces ; 4(4): 1963-71, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22409429

RESUMEN

Electrospun nanofibrous mats are intensively studied as efficient scaffold materials applied in the fields of tissue engineering, catalysis, and biosensors due to their flexibility and porosity. In this paper, we report a facile route to fabricate gold nanoparticles-poly(vinyl alcohol) (Au NPs-PVA) hybrid water stable nanofibrous mats with tunable densities of Au NPs and further demonstrate the potential application of as-prepared Au NPs-PVA nanofibrous mats as efficient biosensor substrate materials. First, through the designed in situ cross-linkage in coelectrospun PVA-glutaraldehyde nanofibers, water insoluble PVA nanofibrous mats with suitable tensile strength were successfully prepared. Then, 3-mercaptopropyltrimethoxysilane (MPTES) was modified on the surface of obtained PVA nanofibrous films, which triggered successful homogeneous decoration of Au NPs through gold-sulfur bonding interactions. Finally, the Au NPs-PVA nanofibrous mats embedded with horseradish peroxidase (HRP) by electrostatic interactions were used as biosensor substrate materials for H(2)O(2) detection. The fabricated HRP-Au NPs/PVA biosensor showed a highly sensitive detection of H(2)O(2) with a detection limit of 0.5 µM at a signal-to-noise ratio of 3. By modifying other different functional nanaoparticles or enzyme on the PVA nanofibrous film will further expand their potential applications as substrate materials of different biosensors.


Asunto(s)
Técnicas Biosensibles/instrumentación , Oro/química , Nanofibras/química , Nanopartículas/química , Alcohol Polivinílico/química , Adsorción , Técnicas Biosensibles/métodos , Peróxido de Hidrógeno/análisis , Relación Señal-Ruido
19.
Zhonghua Er Ke Za Zhi ; 50(10): 777-81, 2012 Oct.
Artículo en Chino | MEDLINE | ID: mdl-23302570

RESUMEN

OBJECTIVE: To investigate the prevalence and antibiotic resistance of Shigella isolated from children with diarrhea for the guidance of clinical treatment and prevention and control of bacillary dysentery. METHOD: A total of 156 strains of Shigella were isolated from feces of children with diarrhea in Zhejiang Xiaoshan Hospital from January 2008 to December 2010. The antimicrobial resistance of the strains was detected by disk diffusion method and the extended-spectrum beta-lactamases (ESBLs) in these isolates were determined using phenotypic confirmatory test; the isolates of ESBLs producing Shigella sonnei were analyzed by REP-PCR. RESULT: Among 156 strains of Shigella isolated, the most common groups were Shigella sonnei (130 strains, accounting for 83.3%) and Shigella fleaneri (26 strains, accounting for 16.7%), and 81 (51.9%) strains were identified as ESBLs producers, and the positive rates in 2008, 2009 and 2010 were 32.0%, 41.4% and 59.8%, respectively. The results of antibiotic susceptibility test displayed that the resistance rates of ESBLs producing Shigella to ampicillin, cotrimoxazole, cefotaxime, piperacillin were higher than 90%. However, the resistance rates to cefepime, ceftazidime, levofloxacin and ciprofloxacin were low; The resistance of ESBLs producing strains to piperacillin (100% vs. 77.3%), cefotaxime (100% vs. 0), ceftazidime (14.8% vs. 0), cefepime (28.4% vs. 0), cotrimoxazole (95.1% vs. 86.7%) was significantly higher than that of non-ESBLs producing strains (χ(2) = 20.605, 156.000, 12.037, 24.979, 45.040, respectively; P < 0.05). No isolate was resistant to piperacillin/tazobactam and imipenem. There were 7 genotypes among 74 ESBLs producing Shigella sonnei, respectively type A (50), type B (12), type C (8), type D (1), type E (1), type F (1), and type G (1). CONCLUSION: The isolation rate of ESBLs-producing isolate was high in Shigella from pediatric patients with diarrhea, and the number is going up year by year, and these ESBLs producing Shigella sonnei strains in genotype A are dominant in recent years, Piperacillin/tazobactam is the drug of choice for children with ESBLs producing Shigella infection.


Asunto(s)
Diarrea/microbiología , Farmacorresistencia Bacteriana Múltiple , Shigella/genética , beta-Lactamasas/genética , Adolescente , Antibacterianos/farmacología , Niño , Preescolar , Diarrea/tratamiento farmacológico , Diarrea/epidemiología , Heces/microbiología , Femenino , Genotipo , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Epidemiología Molecular , Ácido Penicilánico/análogos & derivados , Ácido Penicilánico/farmacología , Piperacilina/farmacología , Combinación Piperacilina y Tazobactam , Reacción en Cadena de la Polimerasa , Análisis de Secuencia de ADN , Shigella/clasificación , Shigella/efectos de los fármacos , Shigella/aislamiento & purificación , beta-Lactamasas/metabolismo
20.
J Cell Physiol ; 227(1): 194-203, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21391215

RESUMEN

Arsenic contamination is a principal environmental health threat throughout the world. However, little is known about the effect of arsenic on steroidogenesis in granulosa cells (GCs). We found that the treatment of preovulatory GCs with arsenite stimulated progesterone production. A significant increase in serum level of progesterone was observed in female Sprague-Dawley rats following arsenite treatment at a dose of 10 mg/L/rat/day for 7 days. Further experiments demonstrated that arsenite treatment did not change the level of intracellular cyclic AMP (cAMP) or phosphorylated ERK1/2 in preovulatory GCs; however, progesterone production was significantly decreased when cAMP-dependent protein kinase (PKA) or ERK1/2 pathway was inhibited. This implied that the effect of arsenite on progesterone production may require cAMP/PKA and ERK1/2 signaling but not depend on them. Furthermore, we found that arsenite decreased intracellular reactive oxygen species (ROS) but increased the antioxidant glutathione (GSH) levels and mitochondrial membrane potential (ΔΨm) in parallel to the changes in progesterone production. Progesterone antagonist blocked the arsenic-stimulated increase of GSH levels. Arsenite treatment induced caspase-3 activation, although no apoptosis was observed. Inhibition of caspase-3 activity significantly decreased progesterone production stimulated by arsenite or follicle-stimulating hormone (FSH). GSH depletion with buthionine sulfoximine led to cell apoptosis in response to arsenite treatment. Collectively, this study demonstrated for the first time that arsenite stimulates progesterone production through cleaved/active caspase-3-dependent pathway, and the increase of GSH level promoted by progesterone production may protect GCs against apoptosis and maintain the steroidogenesis of GCs in response to arsenite treatment.


Asunto(s)
Arsenitos/toxicidad , Caspasa 3/metabolismo , Células de la Granulosa/efectos de los fármacos , Progesterona/biosíntesis , Transducción de Señal/efectos de los fármacos , Teratógenos/toxicidad , Animales , Western Blotting , Separación Celular , Femenino , Citometría de Flujo , Glutatión/biosíntesis , Células de la Granulosa/metabolismo , Mediciones Luminiscentes , Potencial de la Membrana Mitocondrial , Oxidación-Reducción/efectos de los fármacos , ARN Interferente Pequeño , Radioinmunoensayo , Ratas , Ratas Sprague-Dawley , Especies Reactivas de Oxígeno/metabolismo , Transfección
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