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1.
Chemistry ; 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31486553

RESUMO

(NH4 )2 [Zn2 (O3 PCH2 CH2 COO)2 ]⋅5 H2 O (BIRM-1) is a new metal phosphonate material, synthesized through a simple hydrothermal reaction between zinc nitrate and 3-phosphonopropionic acid, using urea and tetraethylammonium bromide as the reaction medium. In common with other metal-organic framework materials, BIRM-1 has a large three-dimensional porous structure providing potential access to a high internal surface area. Unlike most others, it has the advantage of containing ammonium cations within the pores and has the ability to undergo cation exchange. Additionally, BIRM-1 also exhibits a reversible dehydration behavior involving an amorphization-recrystallization cycle. The ability to undergo ion exchange and dynamic structural behavior are of interest in their own right, but also increase the range of potential applications for this material. Here the crystal structure of this new metal phosphonate and its ion exchange behavior with K+ as an exemplar are studied in detail, and its unusual structure-reviving property reported.

2.
Nano Lett ; 19(9): 6424-6428, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31442060

RESUMO

A new concept for second-harmonic generation (SHG) in an optical nanocircuit is proposed. We demonstrate both theoretically and experimentally that the symmetry of an optical mode alone is sufficient to allow SHG even in centro-symmetric structures made of centro-symmetric material. The concept is realized using a plasmonic two-wire transmission-line (TWTL), which simultaneously supports a symmetric and an antisymmetric mode. We first confirm that emission of second-harmonic light into the symmetric mode of the waveguide is symmetry-allowed when the fundamental excited waveguide modes are either purely symmetric or antisymmetric. We further switch the emission into the antisymmetric mode when a controlled mixture of the fundamental modes is excited simultaneously. Our results open up a new degree of freedom into the designs of nonlinear optical components and should pave a new avenue toward multifunctional nanophotonic circuitry.

3.
Molecules ; 24(2)2019 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-30634658

RESUMO

Two new sesquiterpenoids peltopterins A and B (compounds 1 and 2) and fifty-two known compounds were isolated from the methanol extract of P. pterocarpum and their chemical structures were established through spectroscopic and mass spectrometric analyses. The isolates 40, 43, 44, 47, 48, 51 and 52 exhibited potential inhibitory effects of superoxide anion generation or elastase release.


Assuntos
Fabaceae/química , Sesquiterpenos/isolamento & purificação , Espectrometria de Massas , Estrutura Molecular , Elastase Pancreática/metabolismo , Extratos Vegetais/análise , Folhas de Planta/química , Sesquiterpenos/química , Superóxidos/metabolismo
4.
Materials (Basel) ; 11(12)2018 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-30486518

RESUMO

The phase equilibrium of the Ni⁻Al⁻La ternary system in a nickel-rich region was observed at 800 °C and 1000 °C using scanning electron microscopy backscattered electron imaging, energy dispersive X-ray spectrometry and X-ray diffractometry. The solubility of Al in the Ni5La phase was remeasured at 800 °C and 1000 °C. Herein, we report a new ternary phase, termed Ni2AlLa, confirmed at 800 °C. Its X-ray diffraction (XRD) pattern was indexed and space group determined using Total Pattern Solution (TOPAS), and the suitable lattice parameters were fitted using the Pawley method and selected-area electron diffraction. Ni2AlLa crystallizes in the trigonal system with a space group R3 (no. 146), a = 4.1985 Å and c = 13.6626 Å. A self-consistent set of thermodynamic parameters for the Al⁻La and Ni⁻La binary systems and the Ni⁻Al⁻La ternary system includes a Ni2AlLa ternary phase, which was optimized using the CALPHAD method. The calculated thermodynamic and phase-equilibria data for the binary and ternary systems are consistent with the literature and measured data.

5.
Nano Lett ; 2018 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-30142981

RESUMO

Optical nanoantennas mediate near and far optical fields. Operating a directional nanoantenna in transmitting mode is challenging because the antenna needs to be driven by a nanosized optical frequency generator, which must work at the antenna's resonance frequency and be precisely attached to the antenna's feed with correct polarization. Quantum emitters have been used as optical nanogenerators, but their precise positioning relative to the nanoantenna is technically challenging, setting up a barrier to the practical implementation. One unique source to drive nanoantenna is the photoluminescence from the material of the nanoantenna because the high operational frequency of the antenna reaches the regime for the electronic transitions in matter. Here, we exploit plasmon-modulated photoluminescence (PMPL) as an effective optical source to drive directional nanoantennas. We experimentally realize two technically challenging theoretical proposals, namely, an optical nanospectrometer based on Yagi-Uda nanoantennas and tunable broadband directional emission from log-periodic nanoantennas. Using photoluminescence from the nanoantenna as an optical source promotes practical implementation of transmitting optical nanoantennas.

6.
PLoS One ; 13(8): e0202224, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30096190

RESUMO

We evaluated the prognostic significance of immunologic inhibitory biomarkers in head and neck squamous cell carcinoma (HNSCC) patients undergoing definitive chemoradiotherapy (CRT). Thirty patients were prospectively enrolled. Plasma levels of soluble MHC class I polypeptide-related sequence A (sMICA) and transforming growth factor-ß1 (TGF-ß1) were measured before and 2 weeks after CRT. The median follow-up was 32.9 months (range: 12.4-40.6 months). The pre-treatment sMICA (p < 0.001) and TGF-ß1 (p < 0.001) levels were significantly increased in HNSCC patients, compared to healthy controls. In HNSCC patients, the median pre-CRT and post-CRT sMICA levels were 43.1 pg/mL and 65.3 pg/mL, respectively, while the median pre-CRT and post-CRT TGF-ß1 levels were 57.7 ng/mL and 36.0 ng/mL, respectively. After CRT, 19 patients (63.3%) exhibited persistently elevated sMICA, six patients (20.0%) exhibited persistently elevated TGF-ß1, and five patients (16.7%) exhibited persistently elevated sMICA and TGF-ß1. Patients with persistently elevated sMICA and TGF-ß1 after CRT experienced an earlier tumor progression (p = 0.030), and poor overall survival (p = 0.010). Our results suggest that HNSCC patients who exhibit persistently elevated sMICA and TGF-ß1 levels after CRT are at higher risk of tumor progression or death.

7.
Hu Li Za Zhi ; 65(3): 28-37, 2018 06.
Artigo em Chinês | MEDLINE | ID: mdl-29790137

RESUMO

BACKGROUND: Patients with type 2 diabetes mellitus (T2DM) face a higher risk of diabetic foot neuropathy, which increases the risk of death. The early detection of factors that influence diabetic neuropathy reduces the risk of foot lesions, including foot ulcerations, lower extremity amputation, and mortality. PURPOSE: To explore the demographic, disease-characteristic, health-literacy, and foot-self-care-behavior factors that affect diabetic foot neuropathy in patients with T2DM. METHODS: A case-control study design was employed in which cases (Michigan Neuropathy Screening Instrument, MNSI) ≥ 2 were matched to controls based on age and gender in a medical center. A total of 114 patients diagnosed with T2DM in a medical center were recruited as participants. Data were collected using a structured questionnaire. The collected data were analyzed using Fisher's exact test, Mann-Whitney U test, and logistic regression. RESULTS: The results of multiple logistic regression showed that glycated hemoglobin (B = 1.696, p = .041) and communication and critical health literacy (B = -0.082, p = .034) were significant factors of diabetic foot neuropathy. CONCLUSIONS / IMPLICATIONS FOR PRACTICE: The findings of this study suggest that nurses should assess the health literacy of patients with T2DM before providing health education and should develop a specific foot-care intervention for individuals with poor glycemic control.


Assuntos
Diabetes Mellitus Tipo 2/complicações , Pé Diabético/etiologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
8.
Beilstein J Nanotechnol ; 9: 137-145, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29441259

RESUMO

A simple and straightforward synthetic approach for carbon nanodots (C-dots) is proposed. The strategy is based on a one-step hydrothermal chemical reduction with thiourea and urea, leading to high quantum yield C-dots. The obtained C-dots are well-dispersed with a uniform size and a graphite-like structure. A synergistic reduction mechanism was investigated using Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. The findings show that using both thiourea and urea during the one-pot synthesis enhances the luminescence of the generated C-dots. Moreover, the prepared C-dots have a high distribution of functional groups on their surface. In this work, C-dots proved to be a suitable nanomaterial for imaging of bacteria and exhibit potential for application in bioimaging thanks to their low cytotoxicity.

9.
Opt Express ; 25(17): 20466-20476, 2017 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-29041727

RESUMO

This study presents the low cost fabrication of flexible white-light-emitting diodes (w-LEDs) with nano-honeycomb-structured phosphor films. Extending the dimensions of the nano-honeycomb structures improved the color uniformity of the flexible samples, and the 950-nm pattern sample demonstrated optimal color uniformity because this nano-pattern exhibited an excellent diffusion ability owing to its pitch size. In addition to color uniformity, the use of this nano-pattern improved the luminous efficiency. The 750-nm pattern exhibited the highest luminous efficiency (235.8 lm/W), which was approximately 7% higher than that exhibited by a non-patterned phosphor film sample. Thus, flexible w-LEDs with nano-honeycomb structure optimization have great potential to be used as next-generation lighting sources.

10.
Sci Rep ; 7: 43492, 2017 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-28262761

RESUMO

Autoimmune hypophysitis (AH) is a chronic inflammatory disease characterized by infiltration of T and B lymphocytes in the pituitary gland. The mechanisms through which infiltrating lymphocytes cause disease remain unknown. Using a mouse model of AH we assessed whether T lymphocytes undergo activation in the pituitary gland. Infiltrating T cells co-localized with dendritic cells in the pituitary and produced increased levels of interferon-γ and interleukin-17 upon stimulation in vitro. Assessing proliferation of CD3- and B220-postive lymphocytes by double immunohistochemistry (PCNA-staining) and flow cytometry (BrdU incorporation) revealed that a discrete proportion of infiltrating T cells and B cells underwent proliferation within the pituitary parenchyma. This proliferation persisted into the late disease stage (day 56 post-immunization), indicating the presence of a continuous generation of autoreactive T and B cells within the pituitary gland. T cell proliferation in the pituitary was confirmed in patients affected by autoimmune hypophysitis. In conclusion, we show that pituitary-infiltrating lymphocytes proliferate in situ during AH, providing a previously unknown pathogenic mechanism and new avenues for treatment.


Assuntos
Hipofisite Autoimune/imunologia , Hipofisite Autoimune/patologia , Ativação Linfocitária/imunologia , Hipófise/imunologia , Hipófise/patologia , Linfócitos T/imunologia , Animais , Linfócitos B/imunologia , Linfócitos B/metabolismo , Linfócitos B/patologia , Biomarcadores , Proliferação de Células , Citocinas/metabolismo , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Modelos Animais de Doenças , Feminino , Imuno-Histoquímica , Imunofenotipagem , Mediadores da Inflamação/metabolismo , Contagem de Linfócitos , Camundongos , Linfócitos T/metabolismo
11.
Cell Biol Int ; 41(3): 345-352, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28035725

RESUMO

Cyclophosphamide is indicated for the treatment of cancerous diseases such as breast cancer and cervical cancer. Recent studies have shown that cyclophosphamide may induce cancer metastasis, but the cause of this unexpected adverse effect is not fully understood. In this study, we investigate the effect of cyclophosphamide on cancer cell migration and its correlation to chemokine (C-X-C motif) receptor 4 (CXCR4), a biomarker for cancer metastasis. Two human cancer cell lines with significant difference in endogenous CXCR4 expression, the breast cancer cell line, MDA-MB-231, and the melanoma cell line, MDA-MB-435S, were treated with various concentrations of cyclophosphamide, followed by the assessment of CXCR4 expression and cell migration. We found that the migration ability of MDA-MB-231 cells was enhanced with increasing concentrations of cyclophosphamide, which induced the cell-surface expression of CXCR4, but had no effect on the overall amount of CXCR4. In MDA-MB-435S cells, in which CXCR4 was barely detectable, cyclophosphamide was unable to activate cell-surface CXCR4, and did not promote cell migration. Studies on the mRNA expression profile of matrix metalloproteinases (MMPs) in MDA-MB-231 cells further indicate that MMP9 and MMP13 may be involved in the action of cyclophosphamide. The protein expression of both MMP9 and MMP13 was increased in the presence of cyclophosphamide. Results from this study provide the molecular basis for the possible pathway of cyclophosphamide to induce cancer metastasis.


Assuntos
Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Movimento Celular/fisiologia , Ciclofosfamida/toxicidade , Metaloproteinases da Matriz/biossíntese , Receptores CXCR4/biossíntese , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Humanos
12.
PLoS One ; 11(12): e0169005, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28030645

RESUMO

The adipocyte is unique in its capacity to store lipids. In addition to triglycerides, the adipocyte stores a significant amount of cholesterol. Moreover, obese adipocytes are characterized by a redistribution of cholesterol with depleted cholesterol in the plasma membrane, suggesting that cholesterol perturbation may play a role in adipocyte dysfunction. We used methyl-ß-cyclodextrin (MßCD), a molecule with high affinity for cholesterol, to rapidly deplete cholesterol level in differentiated 3T3-L1 adipocytes. We tested whether this perturbation altered adipocyte secretion of monocyte chemoattractant protein-1 (MCP-1), a chemokine that is elevated in obesity and is linked to obesity-associated chronic diseases. Depletion of cholesterol by MßCD increased MCP-1 secretion as well as the mRNA and protein levels, suggesting perturbation at biosynthesis and secretion. Pharmacological inhibition revealed that NF-κB, but not MEK, p38 and JNK, was involved in MßCD-stimulated MCP-1 biosynthesis and secretion in adipocytes. Finally, another cholesterol-binding drug, filipin, also induced MCP-1 secretion without altering membrane cholesterol level. Interestingly, both MßCD and filipin disturbed the integrity of lipid rafts, the membrane microdomains enriched in cholesterol. Thus, the depletion of membrane cholesterol in obese adipocytes may result in dysfunction of lipid rafts, leading to the elevation of proinflammatory signaling and MCP-1 secretion in adipocytes.


Assuntos
Adipócitos/metabolismo , Quimiocina CCL2/metabolismo , Colesterol/metabolismo , Microdomínios da Membrana/patologia , NF-kappa B/metabolismo , Células 3T3-L1 , Adipócitos/citologia , Animais , Diferenciação Celular , Regulação da Expressão Gênica/efeitos dos fármacos , Microdomínios da Membrana/metabolismo , Camundongos , Transdução de Sinais , beta-Ciclodextrinas/farmacologia
13.
Inorg Chem ; 55(24): 12686-12695, 2016 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-27989190

RESUMO

Cs2TiNb6O18 is a potential ceramic wasteform for the long-term immobilization of radioactive cesium. Cs2TiNb6O18 was synthesized using the aqueous precursor method and a solid-state reaction, and its crystal structure was determined from the Rietveld refinement of synchrotron X-ray and neutron powder diffraction data. The structure is a pyrochlore analogue, space group P3̅m1 with Cs in 9-fold coordination. The calculated bond valence sum from analysis of neutron diffraction data of 0.84 and high coordination number suggest that Cs has a strong bonding environment. The chemical aqueous durability was investigated using the MCC-1 and PCT-B standard test methods. The measured Cs leach rates of 3.8 × 10-3 and 2.1 × 10-3 g m-2 day-1 obtained via the MCC-1 and PCT-B methods, respectively, demonstrate good promise of a safe long-term immobilization material comparable to, if not better than, hollandite-the material in the multiphase titanate ceramics (Synroc) targeted for cesium sequestration.

14.
Sensors (Basel) ; 16(8)2016 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-27537887

RESUMO

Fast hexavalent chromium (Cr(VI)) determination is important for environmental risk and health-related considerations. We used a microbial fuel cell-based biosensor inoculated with a facultatively anaerobic, Cr(VI)-reducing, and exoelectrogenic Ochrobactrum anthropi YC152 to determine the Cr(VI) concentration in water. The results indicated that O. anthropi YC152 exhibited high adaptability to pH, temperature, salinity, and water quality under anaerobic conditions. The stable performance of the microbial fuel cell (MFC)-based biosensor indicated its potential as a reliable biosensor system. The MFC voltage decreased as the Cr(VI) concentration in the MFC increased. Two satisfactory linear relationships were observed between the Cr(VI) concentration and voltage output for various Cr(VI) concentration ranges (0.0125-0.3 mg/L and 0.3-5 mg/L). The MFC biosensor is a simple device that can accurately measure Cr(VI) concentrations in drinking water, groundwater, and electroplating wastewater in 45 min with low deviations (<10%). The use of the biosensor can help in preventing the violation of effluent regulations and the maximum allowable concentration of Cr(VI) in water. Thus, the developed MFC biosensor has potential as an early warning detection device for Cr(VI) determination even if O. anthropi YC152 is a possible opportunistic pathogen.


Assuntos
Fontes de Energia Bioelétrica/microbiologia , Técnicas Biossensoriais/métodos , Cromo/isolamento & purificação , Ochrobactrum anthropi/química , Anaerobiose , Cromo/toxicidade , Ochrobactrum anthropi/genética , Esgotos/química , Esgotos/microbiologia , Águas Residuárias/química , Purificação da Água/métodos
15.
PLoS One ; 11(7): e0159681, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27448242

RESUMO

This study developed a novel and inexpensive detection method based on a TaqMan probe-based insulated isothermal polymerase chain reaction (iiPCR) method for the rapid detection of Panama disease caused by Fusarium oxysporum f. sp. cubense (Foc) race 4, which is currently among the most serious fungal vascular diseases worldwide. By using the portable POCKIT™ device with the novel primer set iiFoc-1/iiFoc-2, the Foc race 4 iiPCR assay (including DNA amplification and signal monitoring) could be completed within one hour. The developed Foc race 4 iiPCR assay is thus a user-friendly and efficient platform designed specifically for the detection of Foc race 4. The detection limit of this optimized Foc iiPCR system was estimated to be 1 copy of the target standard DNA as well as 1 fg of the Foc genomic DNA. This approach can serve as a rapid detection method for in planta detection of Foc race 4 in field-infected banana. It was concluded that this molecular detection procedure based on iiPCR has good potential for use as an efficient detection method.


Assuntos
Fusarium/genética , Musa/microbiologia , Doenças das Plantas/microbiologia , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase em Tempo Real/métodos , Sensibilidade e Especificidade
16.
Angew Chem Int Ed Engl ; 55(25): 7222-6, 2016 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-27136738

RESUMO

Au-Pd core-shell nanocrystals with tetrahexahedral (THH), cubic, and octahedral shapes and comparable sizes were synthesized. Similar-sized Au and Pd cubes and octahedra were also prepared. These nanocrystals were used for the hydrogen-evolution reaction (HER) from ammonia borane. Light irradiation can enhance the reaction rate for all the catalysts. In particular, Au-Pd THH exposing {730} facets showed the highest turnover frequency for hydrogen evolution under light with 3-fold rate enhancement benefiting from lattice strain, modified surface electronic state, and a broader range of light absorption. Finite-difference time-domain (FDTD) simulations show a stronger electric field enhancement on Au-Pd core-shell THH than those on other Pd-containing nanocrystals. Light-assisted nitro reduction by ammonia borane on Au-Pd THH was also demonstrated. Au-Pd tetrahexahedra supported on activated carbon can act as a superior recyclable plasmonic photocatalyst for hydrogen evolution.

17.
J Biotechnol ; 220: 78-85, 2016 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-26795354

RESUMO

Porcine circovirus type 2 (PCV2) capsid (Cap) protein has been successfully used as a vaccine to control porcine circovirus associated disease (PCVAD). Most PCV2 subunit vaccines are recombinant Cap protein expressed in baculovirus/insect cell expression system, but using this eukaryotic system is laborious and expensive. In our previous study, full-length of PCV2Cap protein expressed in Escherichia coli formed virus-like particles (VLPs). This expression system has the advantages of being relatively simple and inexpensive. In this study, we constructed a recombinant plasmid containing the full-length codon-optimized cap (ORF2) gene to improve high-level expression of recombinant Cap protein (rCap) with no changed amino acids. The highly water-soluble rCap protein was purified by a single-column, high-throughput fractionation procedure based on size exclusion chromatography. Yield was 10mg per 200ml bacterial culture. The rCap protein self-assembled into VLPs of diameter 25-30nm that contained exogenous nucleic acids. The immunogenicity of PCV2 VLPs was analyzed by immunizing mice. VLP-immunized mice mounted specific immune responses to PCV2. Thus, expression of rCap in E. coli was feasible for large-scale production of PCV2 VLPs, which could potentially be used for a VLP-based PCV2 vaccine.


Assuntos
Infecções por Circoviridae/virologia , Circovirus/genética , Escherichia coli/química , Escherichia coli/metabolismo , Vacinas de Partículas Semelhantes a Vírus/biossíntese , Vacinas de Partículas Semelhantes a Vírus/genética , Animais , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Formação de Anticorpos , Western Blotting/métodos , Proteínas do Capsídeo/biossíntese , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/imunologia , Proteínas do Capsídeo/isolamento & purificação , Cromatografia em Gel/métodos , Infecções por Circoviridae/genética , Infecções por Circoviridae/imunologia , Circovirus/imunologia , Circovirus/metabolismo , Clonagem Molecular , Eletroforese em Gel de Poliacrilamida/métodos , Ensaio de Imunoadsorção Enzimática , ELISPOT/métodos , Escherichia coli/genética , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Microscopia Eletrônica de Transmissão , Dados de Sequência Molecular , Testes de Neutralização , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/isolamento & purificação , Alinhamento de Sequência , Suínos , Doenças dos Suínos/imunologia , Doenças dos Suínos/prevenção & controle , Doenças dos Suínos/virologia , Vacinas de Subunidades , Vacinas de Partículas Semelhantes a Vírus/imunologia , Vírion/genética
18.
Environ Technol ; 35(1-4): 286-93, 2014 Jan-Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24600867

RESUMO

Microbial fuel cells (MFCs) can, besides running on wastewater, also derive energy directly from certain aquatic plants. However, few studies have focussed on electricity generation using aerobic anodes. This study presents a comparison of the MFC performances of an anaerobic-anode MFC (ana-MFC) and an aerobic-anode MFC (aa-MFC), and shows their individual conditions for optimal operation. Results show that the maximum power density of 7.07 +/- 0.45 mW/m2 for the ana-MFC occurred at 500 omega, whereas the aa-MFC had a maximum power density of 2.34 +/- 0.16 mW/m2 at 2200 omega. The ana-MFC generally achieved high electricity generation, and the aa-MFC achieved relatively high electricity generation when fed with a diluted substrate. In the ana-MFC, the optimal substrate for electricity generation was glucose (fermentable substrate); however, glucose and acetic acid (non-fermentable substrate) were both suitable substrates for the aa-MFC. The optimal gas retention times of the ana-MFC and the aa-MFC were 9 and 120 s, respectively. This retention time is an important limiting factor of electricity generation for the ana-MFC. The aa-MFCs fed with different substrates exhibited non-significant differences between bacterial communities. We observed the relative diversities of bacterial communities in the ana-MFC fed with various substrates. The results of denaturing gradient gel electrophoresis analysis suggest that Ochrobactrum intermedium, Delftia acidovorans, and Citrobacterfreundii may be potential electrogenic bacteria. To our knowledge, this is the first study comparing the MFC performances of anaerobic and aerobic anodes.


Assuntos
Fenômenos Fisiológicos Bacterianos , Fontes de Energia Bioelétrica/microbiologia , Eletrodos/microbiologia , Transferência de Energia , Desenho de Equipamento , Análise de Falha de Equipamento
19.
J Cell Biochem ; 114(12): 2718-28, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23794266

RESUMO

Polyamines are naturally occurring organic polycations that are ubiquitous in all organisms, and are essential for cell proliferation and differentiation. Although polyamines are involved in various cellular processes, their roles in stem cell differentiation are relatively unexplored. In this study, we found that exogenous polyamines, putrescine, spermidine, and spermine, promoted osteogenic differentiation of human bone marrow-derived mesenchymal stem cells (hBMSCs) without inducing cell death or apoptosis. Alkaline phosphatase (ALP) activity and the mRNA level of osteogenic genes, including Runx2, ALP, osteopontin, and osteocalcin, were up-regulated by exogenous polyamines. When hBMSCs were cultured at high cell density favoring adipocyte formation, exogenous polyamines resulted in down-regulation of adipogenic genes such as PPARγ, aP2, and adipsin. Extracellular matrix mineralization, a marker for osteoblast maturation, was enhanced in the presence of exogenous polyamines, while lipid accumulation, an indication of adipogenic differentiation, was attenuated. Exogenous polyamines increased the mRNA expression of polyamine-modulated factor 1 (PMF-1) and its downstream effector, spermidine/spermine N(1)-acetyltransferase (SSAT), while that of ornithine decarboxylase (ODC), the rate-limiting enzyme in polyamine biosynthesis, was suppressed. These results lead to possible connections between polyamine metabolism and osteogenic differentiation pathways. To summarize, this study provides evidence for the involvement of polyamines in osteogenic differentiation of hBMSCs, and is the first to demonstrate that osteogenic and adipogenic differentiation are reciprocally regulated by exogenous polyamines.


Assuntos
Adipogenia/genética , Osteogênese/genética , Putrescina/metabolismo , Espermidina/metabolismo , Espermina/metabolismo , Fosfatase Alcalina/metabolismo , Células da Medula Óssea/citologia , Células da Medula Óssea/metabolismo , Diferenciação Celular , Linhagem Celular , Proliferação de Células , Subunidade alfa 1 de Fator de Ligação ao Core/biossíntese , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Células-Tronco Mesenquimais/citologia
20.
Clin Interv Aging ; 8: 667-73, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23766642

RESUMO

PURPOSE: We used the Short Form (SF)-36® Health Survey scale to assess the effect of pelvic floor muscle exercise (PFE) on aging males who received transurethral resection of the prostate (TUR-P). METHODS: From April 2010 to December 2010, a total of 66 patients who underwent TUR-P were enrolled in this study. They were randomized into two groups (with 33 patients in each group) - an experimental group who performed postoperative PFE every day and a control group. Data, including the International Prostate Symptom Score (IPSS), uroflowmetry study, and the SF-36 quality of life measure, were collected before the operation, and at 1, 4, 8, and 12 weeks after the operation. We analyzed the differences between the two groups with respect to their IPSS scores, maximal urinary flow rate, residual urine amount, and life quality. RESULTS: A total of 61 patients (experimental group: 32 patients, and control group: 29 patients) completed this study. We found that at 12 weeks postop, patients who performed PFE every day had a better maximal urinary flow rate (16.41 ± 6.20 vs 12.41 ± 7.28 mL/min) (P = 0.026) compared with patients in the control group. The experimental group had a much greater decrease in IPSS score (P < 0.001). As for the SF-36 scale, the experimental group had higher scores than did the control group on both the physiological domain (54.86 vs 49.86) (P = 0.029) and the psychological domain (61.88 vs 52.69) (P = 0.005). However, there were no significant differences with respect to the postvoiding residual urine between the two groups (57.24 ± 52.95 vs 64.68 ± 50.63 mL) (P = 0.618). CONCLUSION: Compared with the control group, patients who performed PFE for 12 weeks after TUR-P showed improvement in their maximal urinary flow rate and lower urinary tract symptoms, and had a better quality of life. The immediate initiation of PFE is suggested for patients who undergo TUR-P.


Assuntos
Terapia por Exercício/métodos , Diafragma da Pelve/fisiologia , Hiperplasia Prostática/cirurgia , Qualidade de Vida , Ressecção Transuretral da Próstata , Idoso , Idoso de 80 Anos ou mais , Distribuição de Qui-Quadrado , Eletromiografia , Humanos , Sintomas do Trato Urinário Inferior , Masculino , Pessoa de Meia-Idade , Estatísticas não Paramétricas , Inquéritos e Questionários , Resultado do Tratamento , Urodinâmica
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