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1.
Small ; 17(32): e2100840, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34197017

RESUMO

Li-rich layered oxide materials are considered promising candidates for high-capacity cathodes for battery applications and improving the reversibility of the anionic redox reaction is the key to exploiting the full capacity of these materials. However, permanent structural change of the electrode occurring upon electrochemical cycling results in capacity and voltage decay. In view of these factors, Ti4+ -substituted Li2 IrO3 (Li2 Ir0.75 Ti0.25 O3 ) is synthesized, which undergoes an oxygen redox reaction with suppressed voltage decay, yielding improved electrochemical performance and good capacity retention. It is shown that the increased bond covalency upon Ti4+ substitution results in structural stability, tuning the phase stability from O3 to O1' upon de-lithiation during charging compared with O3 to T3 and O1 for pristine Li2 IrO3 , thereby facilitating the oxidation of oxygen. This work unravels the role of Ti4+ in stabilizing the cathode framework, providing insight for a fundamental design approach for advanced Li-rich layered oxide battery materials.

2.
Small ; 16(20): e2001090, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32329570

RESUMO

In this work, rhombohedral KTi2 (PO4 )3 is introduced to investigate the related theoretical, structural, and electrochemical properties in K cells. The suggested KTi2 (PO4 )3 modified by electro-conducting carbon brings about a flat voltage profile at ≈1.6 V, providing a large capacity of 126 mAh (g-phosphate)-1 , corresponding to 98.5% of the theoretical capacity, with 89% capacity retention for 500 cycles. Structural analyses using electrochemical performance measurements, first-principles calculations, ex situ X-ray absorption spectroscopy, and operando X-ray diffraction provide new insights into the reaction mechanism controlling the (de)intercalation of potassium ions into the host KTi2 (PO4 )3 structure. It is observed that a biphasic redox process by Ti4+/3+ occurs upon discharge, whereas a single-phase reaction followed by a biphasic process occurs upon charge. Along with the structural refinement of the electrochemically reduced K3 Ti2 (PO4 )3 phase, these new findings provide insight into the reaction mechanism in Na superionic conductor (NASICON)-type KTi2 (PO4 )3 . The present approach can also be extended to the investigation of other NASICON-type materials for potassium-ion batteries.

3.
Small ; 14(2)2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29171932

RESUMO

Na/FeSx batteries have remarkable potential applicability due to their high theoretical capacity and cost-effectiveness. However, realization of high power-capability and long-term cyclability remains a major challenge. Herein, ultrafine Fe7 S8 @C nanocrystals (NCs) as a promising anode material for a Na-ion battery that addresses the above two issues simultaneously is reported. An Fe7 S8 core with quantum size (≈10 nm) overcomes the kinetic and thermodynamic constraints of the Na-S conversion reaction. In addition, the high degree of interconnection through carbon shells improves the electronic transport along the structure. As a result, the Fe7 S8 @C NCs electrode achieves excellent power capability of 550 mA h g-1 (≈79% retention of its theoretical capacity) at a current rate of 2700 mA g-1 . Furthermore, a conformal carbon shell acts as a buffer layer to prevent severe volume change, which provides outstanding cyclability of ≈447 mA h g-1 after 1000 cycles (≈71% retention of the initial charge capacity).

4.
J Am Chem Soc ; 136(11): 4201-11, 2014 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-24571280

RESUMO

The development of a water oxidation catalyst has been a demanding challenge for the realization of overall water-splitting systems. Although intensive studies have explored the role of Mn element in water oxidation catalysis, it has been difficult to understand whether the catalytic capability originates mainly from either the Mn arrangement or the Mn valency. In this study, to decouple these two factors and to investigate the role of Mn valency on catalysis, we selected a new pyrophosphate-based Mn compound (Li2MnP2O7), which has not been utilized for water oxidation catalysis to date, as a model system. Due to the monophasic behavior of Li2MnP2O7 with delithiation, the Mn valency of Li(2-x)MnP2O7 (x = 0.3, 0.5, 1) can be controlled with negligible change in the crystal framework (e.g., volume change ~1%). Moreover, inductively coupled plasma mass spectrometry, X-ray photoelectron spectroscopy, ex-situ X-ray absorption near-edge structure, galvanostatic charging-discharging, and cyclic voltammetry analysis indicate that Li(2-x)MnP2O7 (x = 0.3, 0.5, 1) exhibits high catalytic stability without additional delithiation or phase transformation. Notably, we observed that, as the averaged oxidation state of Mn in Li(2-x)MnP2O7 increases from 2 to 3, the catalytic performance is enhanced in the series Li2MnP2O7 < Li(1.7)MnP2O7 < Li(1.5)MnP2O7 < LiMnP2O7. Moreover, Li2MnP2O7 itself exhibits superior catalytic performance compared with MnO or MnO2. Our study provides valuable guidelines for developing an efficient Mn-based catalyst under neutral conditions with controlled Mn valency and atomic arrangement.

5.
J Am Chem Soc ; 135(37): 13870-8, 2013 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-23952799

RESUMO

Large-scale electric energy storage is a key enabler for the use of renewable energy. Recently, the room-temperature Na-ion battery has been rehighlighted as an alternative low-cost technology for this application. However, significant challenges such as energy density and long-term stability must be addressed. Herein, we introduce a novel cathode material, Na1.5VPO4.8F0.7, for Na-ion batteries. This new material provides an energy density of ~600 Wh kg(-1), the highest value among cathodes, originating from both the multielectron redox reaction (1.2 e(-) per formula unit) and the high potential (~3.8 V vs Na(+)/Na) of the tailored vanadium redox couple (V(3.8+)/V(5+)). Furthermore, an outstanding cycle life (~95% capacity retention for 100 cycles and ~84% for extended 500 cycles) could be achieved, which we attribute to the small volume change (2.9%) upon cycling, the smallest volume change among known Na intercalation cathodes. The open crystal framework with two-dimensional Na diffusional pathways leads to low activation barriers for Na diffusion, enabling excellent rate capability. We believe that this new material can bring the low-cost room-temperature Na-ion battery a step closer to a sustainable large-scale energy storage system.

6.
Nanotechnology ; 24(42): 424008, 2013 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-24067596

RESUMO

Porous silicon nanowire is fabricated by a simple electrospinning process combined with a magnesium reduction; this material is investigated for use as an anode material for lithium rechargeable batteries. We find that the porous silicon nanowire electrode from the simple and scalable method can deliver a high reversible capacity with an excellent cycle stability. The enhanced performance in terms of cycling stability is attributed to the facile accommodation of the volume change by the pores in the interconnect and the increased electronic conductivity due to a multi-level carbon coating during the fabrication process.

7.
Restor Dent Endod ; 48(2): e18, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37284346

RESUMO

Objectives: This study aimed to determine whether collagen triple helix repeat containing-1 (CTHRC1), which is involved in vascular remodeling and bone formation, can stimulate odontogenic differentiation and angiogenesis when administered to human dental pulp stem cells (hDPSCs). Materials and Methods: The viability of hDPSCs upon exposure to CTHRC1 was assessed with the WST-1 assay. CTHRC1 doses of 5, 10, and 20 µg/mL were administered to hDPSCs. Reverse-transcription polymerase reaction was used to detect dentin sialophosphoprotein, dentin matrix protein 1, vascular endothelial growth factor, and fibroblast growth factor 2. The formation of mineralization nodules was evaluated using Alizarin red. A scratch wound assay was conducted to evaluate the effect of CTHRC1 on cell migration. Data were analyzed using 1-way analysis of variance followed by the Tukey post hoc test. The threshold for statistical significance was set at p < 0.05. Results: CTHRC1 doses of 5, 10, and 20 µg/mL had no significant effect on the viability of hDPSCs. Mineralized nodules were formed and odontogenic markers were upregulated, indicating that CTHRC1 promoted odontogenic differentiation. Scratch wound assays demonstrated that CTHRC1 significantly enhanced the migration of hDPSCs. Conclusions: CTHRC1 promoted odontogenic differentiation and mineralization in hDPSCs.

8.
BMC Complement Altern Med ; 12: 171, 2012 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-23031211

RESUMO

BACKGROUND: This study aims to investigate anti-inflammatory effect of ethanolic extract of Myagropsis myagroides (EMM) in the lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages and the phorbol 12-myristate 13-acetate (PMA)-induced ear edema in mice, and to clarify its underlying molecular mechanisms. METHODS: The levels of nitric oxide (NO), prostaglandin E2 (PGE2), and pro-inflammatory cytokines were measured by Griess assay and enzyme linked immunosorbent assay. The expressions of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), mitogen-activated protein kinases (MAPKs), and Akt were measured using Western blotting. Nuclear translocation and transcriptional activation of nuclear factor-κB (NF-κB) were determined by immunocytochemistry and reporter gene assay, respectively. PMA-induced mouse ear edema was used as the animal model of inflammation. Anti-inflammatory compounds in EMM were isolated using high-performance liquid chromatography and identified by nuclear magnetic resonance. RESULTS: EMM significantly inhibited the production of NO, PGE2, and pro-inflammatory cytokines in a dose-dependent manner and suppressed the expression of iNOS and COX-2 in LPS-stimulated RAW 264.7 cells. EMM strongly suppressed nuclear translocation of NF-κB by preventing degradation of inhibitor of κB-α as well as by inhibiting phosphorylation of Akt and MAPKs. EMM reduced ear edema in PMA-induced mice. One of the anti-inflammatory compounds in EMM was identified as 6,6'-bieckol. CONCLUSIONS: These results suggest that the anti-inflammatory properties of EMM are associated with the down-regulation of iNOS, COX-2, and pro-inflammatory cytokines through the inhibition of NF-κB pathway in LPS-stimulated macrophages.


Assuntos
Anti-Inflamatórios/uso terapêutico , Edema/tratamento farmacológico , Mediadores da Inflamação/metabolismo , Inflamação/prevenção & controle , Phaeophyceae/química , Fitoterapia , Extratos Vegetais/uso terapêutico , Animais , Anti-Inflamatórios/análise , Anti-Inflamatórios/farmacologia , Transporte Biológico , Dioxinas/análise , Dioxinas/farmacologia , Dioxinas/uso terapêutico , Orelha , Inflamação/induzido quimicamente , Inflamação/metabolismo , Lipopolissacarídeos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos ICR , Extratos Vegetais/química , Extratos Vegetais/farmacologia
9.
ACS Appl Mater Interfaces ; 13(17): 19970-19982, 2021 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-33880915

RESUMO

Cylindrical-type cells have been widely adopted by major battery and electric vehicle manufacturers owing to their price competitiveness, safety, and easy expandability. However, placement of electrodes at the core of cylindrical cells is currently restricted because of high electrode curvature and the lack of specialized electrodes and electrode materials. Here, we report the realization of highly flexible high-energy-density electrodes (active material loading of >98.4%) that can be used at the cores of cylindrical cells. The improved properties result from the introduction of a multifunctional poly(melamine-co-formaldehyde) (MF copolymer) additive, which yields a relatively more fluidic and well-dispersed slurry using only 0.08 wt %. MF copolymer-mediated formation of completely wrapped CNT/PVDF networks on LiCoO2 (LCO) and accompanying contact enhancement between LCO and carbon nanotubes (CNTs) resulted in an increase of electrical and mechanical properties of the two types (composites with or without collectors) of electrodes compared with those of additive-free electrodes. Flexibility tests were carried out by rolling electrodes onto cylinder substrates (diameters of ca. 1 and 10 mm); this process resulted in relatively lower resistance changes of the MF copolymer-containing electrodes than for the reference electrodes. In addition, capacity retention after 100 cycles for cells with and without MF copolymers was approximately 10-20% better for the samples with the MF copolymer than for those without. CNT/PVDF networks with MF copolymers were proven to induce a relatively thin and stable cathode electrolyte interface layer accompanying the chemical bond formation during cycling.

10.
ACS Appl Mater Interfaces ; 13(15): 17978-17987, 2021 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-33821600

RESUMO

Functional separators, which are chemically modified and coated with nanostructured materials, are considered an effective and economical approach to suppressing the shuttle effect of lithium polysulfide (LiPS) and promoting the conversion kinetics of sulfur cathodes. Herein, we report cobalt-aluminum-layered double hydroxide quantum dots (LDH-QDs) deposited with nitrogen-doped graphene (NG) as a bifunctional separator for lithium-sulfur batteries (LSBs). The mesoporous LDH-QDs/NG hybrids possess abundant active sites of Co2+ and hydroxide groups, which result in capturing LiPSs through strong chemical interactions and accelerating the redox kinetics of the conversion reaction, as confirmed through X-ray photoelectron spectroscopy, adsorption tests, Li2S nucleation tests, and electrokinetic analyses of the LiPS conversion. The resulting LDH-QDs/NG hybrid-coated polypropylene (LDH-QDs/NG/PP) separator, with an average thickness of ∼17 µm, has a high ionic conductivity of 2.67 mS cm-1. Consequently, the LSB cells with the LDH-QDs/NG/PP separator can deliver a high discharge capacity of 1227.48 mAh g-1 at 0.1C along with a low capacity decay rate of 0.041% per cycle over 1200 cycles at 1.0C.

11.
Korean J Parasitol ; 47(4): 401-4, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19967090

RESUMO

A 33-year-old Korean man visited a medical clinic with complaints of throat discomfort and pain for one week. The symptoms occurred one day after eating raw brackish water fish, perch. Endoscopy revealed a fluke, about 5 mm in length, attaching to and peristaltically moving on the surface of the mucosa at the arytenoid region of the larynx. Microscopically, the testes were triangular, tandem, and separated by the uterus. The ovary and cirrus pouch were placed apart from median line between testes. Numerous blood cells were observed in the ceca. The worm was identified to be Clinostomum complanatum. This is the second human case of clinostomiasis in Korea.


Assuntos
Doenças Transmitidas por Alimentos/diagnóstico , Trematódeos/isolamento & purificação , Infecções por Trematódeos/diagnóstico , Adulto , Estruturas Animais/anatomia & histologia , Animais , Endoscopia , Doenças Transmitidas por Alimentos/parasitologia , Humanos , Coreia (Geográfico) , Laringe/parasitologia , Laringe/patologia , Masculino , Microscopia , Faringe/parasitologia , Faringe/patologia , Trematódeos/anatomia & histologia , Infecções por Trematódeos/parasitologia
12.
ACS Nano ; 13(10): 11707-11716, 2019 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-31600049

RESUMO

Herein, the Cu2P2O7/carbon-nanotube nanocomposite is reported as a cathode material based on a conversion reaction for rechargeable sodium batteries (RSBs). The nanocomposite electrode exhibits the large capacity of 355 mAh g-1, which is consistent with the 4 mol Na+ storage per formula unit determined by first-principles calculation. Its average operation voltage is approximately 2.4 V (vs Na+/Na). Even at 1800 mA g-1, a capacity of 223 mAh g-1 is maintained. Moreover, the composite electrode exhibits acceptable capacity retention of over 75% of the initial capacity for 300 cycles at 360 mA g-1. The overall conversion reaction mechanism on the Cu2P2O7/carbon-nanotube nanocomposite is determined to be Cu2P2O7 + 4Na+ + 4e- → 2Cu + Na4P2O7 based on operando/ex situ structural and physicochemical analyses. The high energy density of the Cu2P2O7/carbon-nanotube nanocomposite (720 Wh kg-1) supported by this conversion chemistry indicates a high possibility of application of this material as a promising cathode candidate for RSBs.

13.
J Exerc Rehabil ; 14(3): 407-412, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30018926

RESUMO

The purpose of this study is to analyze exercise injury experiences of sports participants and the characteristics of sporting activities depending on whether they have injured or not. The subjects of this study included the 107 people who have experienced exercise injuries and the 103 people who have not have experienced exercise injuries with aged between the 20s and 40s. The questionnaire with household interviews was used for this research. The results of this study that the female participants who have experienced an injury while exercise was outnumbered by their male counterparts and it is found that sports participants in their 40s represented the highest ratio and that the two most popular sports the participants who have experienced injury did were body-building and golf. It has been surveyed that the number of hospital care due to exercise injury per year is 2.01 times on average and the amount of money spent on the medical care is 34,252 Korean won on average. It is identified that the level of sports activities that keeping health and perception by the impact of sports activities depending on the participants' exercise injured. It is worthy of notice that those who have experienced exercise injuries tended to show a high level of confidence in which they could benefit from sports activity. In addition, it is interesting to note that bodybuilding and golf were the two sports with a great number of exercise injuries.

14.
Chem Commun (Camb) ; 54(41): 5229-5232, 2018 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-29726560

RESUMO

We demonstrate that hybrid structures of graphene and single-walled carbon nanotubes (SWNTs) are precisely controlled at the liquid-gas interface. The functionalized SWNT Langmuir monolayers anchor single-layer graphene nanosheets (GNSs) suspended in water via Coulomb interaction at the interface. This GNS/SWNT hybrid multilayer electrode can be a promising anode material for Li-ion batteries, offering high specific capacity, outstanding power capability, and excellent cyclability.

15.
ACS Appl Mater Interfaces ; 9(46): 40307-40316, 2017 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-29087179

RESUMO

Li3V2-xMnx(PO4)3 (x = 0, 0.05) cathode materials, which allow extraction of 3 mol of Li from the formula unit, were investigated to achieve a high energy density utilizing multielectron reactions, activated by the V3+/5+ redox reaction. Structural investigation demonstrates that V3+ was replaced by equivalent Mn3+, as confirmed by Rietveld refinement of the X-ray diffraction data and X-ray absorption near edge spectroscopy. The substitution simultaneously lowered the band gap energy from 3.4 to 3.2 eV, according to a density functional theory calculation. In addition to the effect of Mn doping, surface carbonization of Li3V2-xMnx(PO4)3 (x = 0, 0.05) dramatically increased the electric conductivity up to 10-3 S cm-1. As a result, the carbon-coated Li3V2-xMnx(PO4)3 (x = 0.05) delivered a high discharge (reduction) capacity of approximately 180 mAh g-1 at a current of 20 mA g-1 (0.1 C rate) with excellent retention, delivering approximately 163 mAh g-1 at the 200th cycle. Even at 50 C (10 A g-1), the electrode afforded a discharge capacity of 68 mAh g-1 and delivered approximately 104 mAh g-1 (1 C) at -10 °C with the help of Mn doping and carbon coating. The synergetic effects such as a lowered band gap energy by Mn doping and high electric conductivity associated with carbon coating are responsible for the superior electrode performances, including thermal properties with extremely low exothermic heat generation (<0.4 J g-1 for Li0.02V1.95Mn0.05(PO4)3), which is compatible with the layered high energy density of LiNi0.8Co0.15Al0.05O2 and LiNi0.8Co0.1Mn0.1O2 materials.

16.
J Biomed Mater Res B Appl Biomater ; 78(1): 115-23, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16333849

RESUMO

A thick oxygen-inhibited layer (OIL) on a cured adhesive layer (AL) is believed to result in both good adaptation of composite resin (CR) and high bond strength. A high degree of conversion (DC) of the AL is also needed for durable bonding. This study evaluated the hypothesis that increasing the DC by prolonging the light-curing time of adhesive bonding resin might decrease the bond strength of the adhesive to dentin because of the subsequent thinning of the OIL thickness. The OIL thickness and the DC of solvent-removed One Step and D/E bonding resin of All Bond 2 (Bisco, USA) were measured simultaneously with FT-NIR spectroscopy according to increasing light-cure times (10, 20, 30, and 60 s) so as to evaluate their effect on the microtensile bond strength. The bonded interfaces were evaluated using scanning electron microscopy. Excessive irradiation of light-curing adhesives increased the DC, but decreased the OIL thickness. When the OIL was significantly thin by curing the adhesives for 30 or 60 s, defects were observed at the interface between the AL and the CR, as well as at the interface between the AL and the hybrid layer. When the OIL was thick, free radicals from the overlying CR may have diffused into the unreacted monomer mixtures of the OIL, chemically connecting the cured AL and the newly curing composite. It was found that to obtain maximum dentin bond strength, light-curing adhesives should be cured for the irradiation time recommended by the manufacturer.


Assuntos
Adesivos Dentinários/química , Dentina , Oxigênio/antagonistas & inibidores , Humanos , Dente Molar , Espectroscopia de Infravermelho com Transformada de Fourier , Espectroscopia de Luz Próxima ao Infravermelho , Resistência à Tração
17.
J Biomed Mater Res B Appl Biomater ; 72(2): 284-91, 2005 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-15484258

RESUMO

This study evaluated the hypothesis that if hydrophilic nanofillers were dispersed evenly within the adhesive layer under moist conditions, adding them to a one-bottle dentin adhesive might improve the mechanical properties of the adhesive layer, and accordingly increase the bond strength. The flexural strength (FS), the degree of conversion (DC), and the microtensile bond strength (MTBS) to the dentin of four experimental ethanol-based one-bottle dentin adhesives containing 0, 0.5, 1.0, and 3.0 wt % of 12-nm hydrophilic fumed silica were evaluated, and the distribution of the nanofillers were compared using transmission electron microscopy (TEM). Although the nanofiller content did not affect the DC, the FS tended to increase with increasing nanofiller content. The MTBS appeared to increase when up to 1.0 wt % of the nanofillers were added, but they were statistically not significant. However, when 3.0 wt % of the nanofillers were added, the MTBS decreased significantly comparing to the adhesive containing 0.5 wt % nanofillers (p < 0.05). The TEM image suggested that if the nanofillers within the adhesive were 3.0 wt % and applied to a wet dentin surface, they aggregated easily into large clusters and would decrease the MTBS.


Assuntos
Cimentação/métodos , Adesivos Dentinários/normas , Cimentação/normas , Etanol , Interações Hidrofóbicas e Hidrofílicas , Teste de Materiais , Mecânica , Microscopia Eletrônica de Transmissão , Modelos Biológicos , Eletricidade Estática , Propriedades de Superfície , Resistência à Tração
18.
J Biomed Mater Res B Appl Biomater ; 74(2): 822-8, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15991229

RESUMO

The goal of this study is to evaluate the hypothesis that the properties of the resin adhesive might affect the microtensile bond strength (MTBS) of multibottle dental adhesive system. In order to alter the properties, the experimental resin adhesives containing 2,2-bis (4-2-hydroxy-3-methacryloyloxypropoxyphenyl)propane (Bis-GMA) and triethylene glycol dimethacrylate (TEGDMA) at various ratios were prepared. Degree of conversion immediately after curing (DC-immed), degree of conversion at 48 h after curing (DC-48h) of a thin coat of the experimental adhesives, the flexural strength (FS) of the bulk specimens made of the experimental adhesives, pH, viscosity at shear rate of 1 S(-1), and the microtensile bond strength (MTBS) values of the adhesives to dentin were investigated. The maximum MTBS and FS values of the resin adhesives were observed when the ratio of Bis-GMA/TEGDMA was 60/40. However, pH and viscosity values increased with increasing Bis-GMA content in the adhesives. When Bis-GMA content was more than 60 wt %, the viscosity increased exponentially and restricted the DC and FS, and accordingly decreased the bond strength. The stronger the resin adhesives were, the higher the bond strength to dentin could be obtained.


Assuntos
Bis-Fenol A-Glicidil Metacrilato , Adesivos Dentinários , Dentina , Polietilenoglicóis , Ácidos Polimetacrílicos , Bis-Fenol A-Glicidil Metacrilato/química , Adesivos Dentinários/química , Humanos , Concentração de Íons de Hidrogênio , Dente Molar , Polietilenoglicóis/química , Ácidos Polimetacrílicos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Viscosidade
19.
J Bone Joint Surg Am ; 96(7): 543-8, 2014 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-24695920

RESUMO

BACKGROUND: The purpose of this study was to evaluate the association between the postoperative outcomes of anterior cruciate ligament (ACL) reconstruction and the anterior laxity of the uninjured knee. METHODS: We retrospectively reviewed 163 patients who had undergone unilateral ACL reconstruction from January 2002 to August 2009. Patients were divided into three groups according to the anterior laxity of the contralateral, normal knee in 30° of knee flexion as measured with a KT2000 arthrometer exerting a force of 134 N: <5 mm for Group 1, 5 to 7.5 mm for Group 2, and >7.5 mm for Group 3. Anterior laxity of the uninjured knee was assessed preoperatively, and anterior laxity of the reconstructed knee was assessed at twenty-four months postoperatively. Anterior stability of the knee was also assessed with use of the Lachman and pivot-shift tests. Functional outcomes were assessed with the Lysholm score and the International Knee Documentation Committee (IKDC) score. RESULTS: The three groups differed significantly with respect to the postoperative side-to-side difference in anterior laxity (p = 0.015), Lysholm score (p < 0.001), and IKDC subjective score (p < 0.001). The mean side-to-side difference in anterior laxity of the reconstructed knee was 2.1 ± 1.3 mm in Group 1, 2.2 ± 1.3 mm in Group 2, and 2.9 ± 1.4 mm in Group 3. The postoperative Lysholm score was 91.8 ± 4.5 in Group 1, 90.3 ± 5.5 in Group 2, and 85.4 ± 6.6 in Group 3. The postoperative IKDC subjective score was 89.3 ± 6.4 in Group 1, 87.9 ± 6.0 in Group 2, and 82.6 ± 8.2 in Group 3. Post hoc testing showed that Group 3 had significantly greater anterior laxity (p ≤ 0.039) and lower functional scores (p ≤ 0.001) compared with Groups 1 and 2. CONCLUSIONS: Greater anterior laxity of the uninjured knee was associated with poorer stability and functional outcomes after ACL reconstruction. Excessive anterior laxity of the uninjured knee thus appears to represent a risk factor for inferior outcomes.


Assuntos
Reconstrução do Ligamento Cruzado Anterior , Instabilidade Articular/complicações , Traumatismos do Joelho/cirurgia , Adolescente , Adulto , Idoso , Artrometria Articular , Feminino , Indicadores Básicos de Saúde , Humanos , Instabilidade Articular/diagnóstico , Instabilidade Articular/fisiopatologia , Traumatismos do Joelho/complicações , Traumatismos do Joelho/fisiopatologia , Articulação do Joelho/fisiopatologia , Articulação do Joelho/cirurgia , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Período Pós-Operatório , Amplitude de Movimento Articular , Recuperação de Função Fisiológica , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
20.
Am J Chin Med ; 41(3): 565-84, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23711142

RESUMO

Sargassum fulvellum (Turner) C. Agardh has been used to treat various inflammatory diseases, including lump, dropsy, swollen and painful scrotum, and urination problems for several centuries with no side effects. This study aims to investigate the anti-inflammatory effect of the hexane fraction of S. fulvellum (HFS) in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells and phorbol 12-myristate 13-acetate (PMA)-induced mouse-ear edema. The anti-inflammatory activity of HFS in LPS-stimulated RAW 264.7 cells was investigated by assessing the inhibition of nitric oxide (NO) and pro-inflammatory cytokine production during Griess reaction and enzyme-linked immunosorbent assay (ELISA), respectively. The molecular mechanisms that underlie the anti-inflammatory action of HFS were investigated by analyzing the activation of transcription factor and its upstream signaling proteins. Additionally, an in vivo study of the anti-inflammatory effect of HFS was carried out using PMA-induced mouse-ear edema. HFS inhibited LPS-induced NO production in a dose-dependent manner and suppressed the expression of inducible NO synthase (iNOS) in the RAW 264.7 cells. Further, HFS reduced the production of pro-inflammatory cytokines in the LPS-stimulated RAW 264.7 cells. HFS significantly inhibited LPS-induced nuclear factor kappa B (NF-κB) transcriptional activity and NF-κB translocation into the nucleus by preventing degradation of inhibitor κB-α. Moreover, HFS inhibited the activation of Akt and mitogen-activated protein kinases (MAPKs) in the LPS-stimulated RAW 264.7 cells. Furthermore, HFS suppressed PMA-induced mouse-ear edema. The above data indicate that the anti-inflammatory effects of HFS on LPS-stimulated cells are associated with the suppression of NF-κB through the inhibition of MAPKs and Akt phosphorylation.


Assuntos
Anti-Inflamatórios/uso terapêutico , Inflamação/tratamento farmacológico , NF-kappa B/metabolismo , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Óxido Nítrico/antagonistas & inibidores , Fitoterapia , Sargassum , Animais , Anti-Inflamatórios/farmacologia , Transporte Biológico , Linhagem Celular , Citocinas/metabolismo , Relação Dose-Resposta a Droga , Orelha , Edema/tratamento farmacológico , Edema/metabolismo , Inflamação/induzido quimicamente , Inflamação/metabolismo , Lipopolissacarídeos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos ICR , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Transdução de Sinais
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