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1.
J Colloid Interface Sci ; 679(Pt A): 234-242, 2024 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-39362148

RESUMO

Rechargeable non-aqueous lithium-oxygen batteries (LOBs) have garnered increasing attention owing to their high theoretical energy density. However, their slow cathodic kinetics hinder efficient battery reactions. Nanoscale catalysts can effectively enhance electrocatalytic activity and atomic utilization efficiency. However, the agglomeration of nanoscale catalysts (such as cluster and single atoms) during continuous discharge/charge cycles leads to decreased electrochemical performance and poor cyclic stability. Herein, the ruthenium (Ru) atomic sites anchored on an O-doped molybdenum disulfide (O-MoS2) catalyst (designated as Ru/O-MoS2) was fabricated using a facile impregnation and calcination method. Strong Ru-O coupling between Ru atoms and the O-MoS2 substrate optimizes the localized electronic structure, resulting in improved electrochemical performance and enhanced resistance to Ostwald ripening. When employed as a cathode catalyst for LOBs, Ru/O-MoS2 catalyst exhibits a high reversible specific capacity (18700.5 (±59.8) mAh g-1), good rate capability, and enhanced long-term stability (115 cycles, 1200 h). This study encourages facile and efficient strategies for the development of effective and stable electrocatalysts for use in LOBs.

2.
Mar Pollut Bull ; 201: 116199, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38422826

RESUMO

Understanding PAH and OCP distributions and sources in lakes is necessary for developing pollutant control policies. Here, we assessed the occurrence, risk, and sources of PAHs and OCPs in the sediment of Caohai Lake. The PAHs were predominantly high-molecular-weight compounds (mean 57.5 %), and the diagnostic ratios revealed that coal, biomass burning, and traffic were the sources of PAHs. HCHs (6.53 ± 7.22 ng g-1) and DDTs (10.86 ± 12.16 ng g-1) were the dominant OCPs and were primarily sourced from fresh exogenous inputs. RDA showed that sediment properties explained 74.12 % and 65.44 % of the variation in PAH and OCP concentrations, respectively. Incremental lifetime cancer risk (ILCR) assessment indicated that hazardous PAHs in Caohai Lake sediment posed moderate risks to children and adults (ILCR>1.0 × 10-4), while the risk from OCPs was low; however, the recent influx of HCHs and DDTs requires additional attention.


Assuntos
Hidrocarbonetos Clorados , Praguicidas , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Criança , Humanos , Lagos , Áreas Alagadas , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Praguicidas/análise , Hidrocarbonetos Clorados/análise , China , Sedimentos Geológicos
3.
J Colloid Interface Sci ; 628(Pt B): 922-930, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36030717

RESUMO

Efficient nonprecious bifunctional electrocatalysts toward oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) are essential for improving the electrochemical performance of Zinc-air (Zn-air) batteries. Herein, we report a cobalt-doped Mn2(OH)3VO3 catalyst prepared by facile hydrothermal method, and the ratios of cationic redox couples of catalysts were tuned with different Co doping amounts. The as-prepared Mn1.8Co0.2(OH)3VO3 (MnCoVO-1) catalyst achieves the highest ratio of (Mn3+Mn4+)/Mn2+ and Co3+/Co2+ redox couples which serve as ORR and OER active sites respectively, and exhibits the enhanced electrocatalytic performance. Furthermore, when employed as air-cathode catalyst for rechargeable Zn-air batteries, the MnCoVO-1 catalyst reveals a high power density (278 mW cm-2), enhanced rate performance and outstanding long-term stability of over 270 h. This work demonstrates the Co-doped Mn2(OH)3VO3 with optimized electronic structure by rational doping engineering can serve as a promising bifunctional catalyst for oxygen electrocatalysis and rechargeable Zn-air batteries.

4.
Small ; 17(4): e2006183, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33377268

RESUMO

Development of highly active, robust electrocatalysts to accelerate the sluggish oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is crucial and challenging for the practical application of metal-air batteries. In this effort, a novel and facile self-jet vapor-phase growth approach is developed, from which highly dispersive FeNi alloy nanoparticles (NPs) encapsulated in N-doped carbon nanotubes (NCNT) grown on a cotton pad (FeNi@NCNT-CP) can be fabricated. The as-prepared FeNi@NCNT-CP clusters exhibit superior bifunctional catalytic activity, with a high half-wave potential of 0.85 V toward ORR and a low potential of 1.59 V at 10 mA cm-2 toward OER. Specifically, owing to the synergistic effects of FeNi alloy NPs and NCNT, FeNi@NCNT-CP clusters deliver excellent stability, demonstrating a small potential gap of 0.73 V between ORR and OER after operation for 10 000 cycles. Furthermore, FeNi@NCNT-CP serves as a cost-effective, superior catalyst for the cathode of a rechargeable Zn-air battery, outperforming a catalyst mixture of expensive Pt/C and IrO2 . FeNi@NCNT-CP provides a maximum power density of 200 mW cm-2 and a cycling stability of up to 250 h. This contribution provides new prospects to prepare non-noble electrocatalysts for metal-air battery cathodes.

5.
J Chem Inf Model ; 58(8): 1587-1595, 2018 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-30067339

RESUMO

Amyloid aggregation initiates from a slow nucleation process, where the association of monomers is unfavorable in energetics. In principle, the enthalpy change for aggregation should compensate the entropy loss as new monomers attach to formed oligomers. However, the classical force fields with fixed point charges failed to yield the correct enthalpy change due to the lack of electrostatic polarization effect on amyloid aggregation. In this work, we performed molecular dynamics simulation for the full-length human islet amyloid using the polarized protein-specific charges and calculated the electrostatic interaction energy for amyloid oligomers. The results of molecular dynamics simulation show that the aggregates simulated with polarized charges have larger enthalpy change than that with fixed charges. The large enthalpy change mainly originates from the electrostatic polarization, which makes a significant contribution to the cooperative effect of aggregation and facilitates the nucleation process of amyloids.


Assuntos
Polipeptídeo Amiloide das Ilhotas Pancreáticas/química , Agregados Proteicos , Amiloide/química , Humanos , Ligação de Hidrogênio , Simulação de Dinâmica Molecular , Conformação Proteica , Eletricidade Estática , Termodinâmica
6.
Med Sci Monit ; 24: 4832-4840, 2018 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-30001299

RESUMO

BACKGROUND Brachial plexus injury (BPI), a severe nervous system injury, is a leading cause of functional damages of the affected upper limb. Patients with BPI manifested with motor weakness or paralysis, sensory deficits, and pain. We established a BPI rat model to explore the in vivo effect of end-to-side screw anastomosis (ETSSA) of phrenic nerve on the recovery of limb function after BPI. MATERIAL AND METHODS After modeling, rats were treated with end-to-side anastomosis (ETSA) and ETSSA respectively. After 1 and 3 months, the behavioral changes of rats were observed using the Terzis grooming test, and the compound muscle action potential (CMAP) and muscle tension of biceps brachii were detected. The muscle weight recovery rate (MWRR) and cross-sectional area recovery rate (CARR) were calculated. Toluidine blue staining was used to observe the myelinated nerve fibers in the proximal phrenic nerve and distal musculocutaneous nerve of suture. The ratio of regenerated nerve traversing rate (NTR) was counted and motor endplate area of biceps brachii was measured. RESULTS The rats treated with ETSA and ETSSA exhibited elevated grading of Terzis grooming test with time. Although both the ETSSA and ETSA can reduce the MWRR, CARR and motor endplate area in BPI rats, ETSSA showed a better influence on the latency delayed rate (LDR) and amplitude recovery rate (ARR) of CMAP, muscular tension recovery rate (MTRR), MWRR, number of regenerated myelinated nerve fibers, NTR, and motor endplate area in BPI rats. CONCLUSIONS Our study provided evidence that ETSSA can restore the limb function recovery to a greater extent, and accelerate the regeneration of nerve fibers in rats with BPI; the effect of ETSSA was better than that of ETSA.


Assuntos
Anastomose Cirúrgica/métodos , Plexo Braquial/cirurgia , Nervo Frênico/cirurgia , Animais , Parafusos Ósseos , Masculino , Neurônios Motores , Músculo Esquelético/inervação , Regeneração Nervosa/fisiologia , Transferência de Nervo/métodos , Procedimentos Neurocirúrgicos , Ratos , Ratos Sprague-Dawley
7.
PLoS One ; 13(5): e0197392, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29768506

RESUMO

The protein kinase (PK, kinome) family is one of the largest families in plants and regulates almost all aspects of plant processes, including plant development and stress responses. Despite their important functions, comprehensive functional classification, evolutionary analysis and expression patterns of the cotton PK gene family has yet to be performed on PK genes. In this study, we identified the cotton kinomes in the Gossypium raimondii, Gossypium arboretum, Gossypium hirsutum and Gossypium barbadense genomes and classified them into 7 groups and 122-24 subfamilies using software HMMER v3.0 scanning and neighbor-joining (NJ) phylogenetic analysis. Some conserved exon-intron structures were identified not only in cotton species but also in primitive plants, ferns and moss, suggesting the significant function and ancient origination of these PK genes. Collinearity analysis revealed that 16.6 million years ago (Mya) cotton-specific whole genome duplication (WGD) events may have played a partial role in the expansion of the cotton kinomes, whereas tandem duplication (TD) events mainly contributed to the expansion of the cotton RLK group. Synteny analysis revealed that tetraploidization of G. hirsutum and G. barbadense contributed to the expansion of G. hirsutum and G. barbadense PKs. Global expression analysis of cotton PKs revealed stress-specific and fiber development-related expression patterns, suggesting that many cotton PKs might be involved in the regulation of the stress response and fiber development processes. This study provides foundational information for further studies on the evolution and molecular function of cotton PKs.


Assuntos
Genoma de Planta/genética , Gossypium/genética , Cromossomos de Plantas/genética , Evolução Molecular , Duplicação Gênica/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/genética , Família Multigênica , Filogenia , Sintenia
8.
J Med Case Rep ; 12(1): 74, 2018 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-29558996

RESUMO

BACKGROUND: Skeletal and soft tissue damage are often associated with unilateral facet dislocations, which undoubtedly lead to instability of the spine and further increase difficulties in cervical reduction. This type of irreducible facet dislocation is usually accompanied with potential catastrophic consequences including neurological deficit and severe disability. Therefore, a consistent and evidence-based treatment plan is imperative. CASE PRESENTATION: The literature regarding the management of traumatic unilateral locked cervical facet dislocations was reviewed. Two patient cases (a 30-year-old Asian man and a 25-year-old Asian woman) who suffered irreducible cervical facet dislocations were presented. These two patients received surgical treatments including posterior reduction by poking facet joints, adjacent spinous process fixation by wire rope banding, anterior plate fixation, and intervertebral fusion after the failure of skull traction and closed reduction. At the postoperative 24-month follow-up, intervertebral fusion was achieved and our patients' neurological status improved based on the American Spinal Injury Association scale, compared with their preoperative status. CONCLUSIONS: Unilateral facet joint dislocations of subaxial cervical spine are difficult to reduce when complicated with posterior facet fractures or ligamentous injury. Magnetic resonance imaging can be beneficial for identifying ventral and dorsal compressive lesions, as well as ligamentous or capsule rupture. The combination of posterior reduction and anterior fixation with fusion has advantages in terms of clinical safety, ease of operation, and less iatrogenic damage.


Assuntos
Vértebras Cervicais/lesões , Descompressão Cirúrgica , Luxações Articulares/cirurgia , Paraplegia/cirurgia , Compressão da Medula Espinal/cirurgia , Fusão Vertebral , Traumatismos da Coluna Vertebral/cirurgia , Articulação Zigapofisária/diagnóstico por imagem , Adulto , Fios Ortopédicos , Vértebras Cervicais/diagnóstico por imagem , Feminino , Seguimentos , Humanos , Disco Intervertebral/lesões , Luxações Articulares/diagnóstico por imagem , Luxações Articulares/fisiopatologia , Imageamento por Ressonância Magnética , Masculino , Paraplegia/etiologia , Paraplegia/fisiopatologia , Recuperação de Função Fisiológica/fisiologia , Compressão da Medula Espinal/diagnóstico por imagem , Compressão da Medula Espinal/fisiopatologia , Fusão Vertebral/métodos , Traumatismos da Coluna Vertebral/diagnóstico por imagem , Traumatismos da Coluna Vertebral/fisiopatologia , Resultado do Tratamento , Articulação Zigapofisária/fisiopatologia , Articulação Zigapofisária/cirurgia
9.
ChemSusChem ; 11(3): 574-579, 2018 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-29235727

RESUMO

Carbon is usually used as cathode material for Li-O2 batteries. However, the discharge product, such as Li2 O2 and LiO2 , could react with carbon to form an insulating lithium carbonate layer, resulting in cathode passivation and capacity fading. To solve this problem, the development of non-carbon cathodes is highly desirable. Herein, we successfully synthesized MnCo2 O4 (MCO) nanoparticles anchored on porous MoO2 nanosheets that are grown on Ni foam (current collector) (MCO/MoO2 @Ni), acting as a carbon- and binder-free cathode for Li-O2 batteries, in an attempt to improve the electrical conductivity, electrocatalytic activity, and durability. This MCO/MoO2 @Ni electrode delivers excellent cyclability (more than 400 cycles) and rate performance (voltage gap of 0.75 V at 5000 mA g-1 ). Notably, the battery with this electrode exhibits a high energy efficiency (higher than 85 %). The advanced electrochemical performance of MCO/MoO2 @Ni can be attributed to its high electrical conductivity, excellent stability, and outstanding electrocatalytic activity. This work offers a new strategy to fabricate high-performance Li-O2 batteries with non-carbon cathode materials.


Assuntos
Carbono/química , Cobalto/química , Fontes de Energia Elétrica , Eletrodos , Lítio/química , Manganês/química , Molibdênio/química , Nanoestruturas , Níquel/química , Óxidos/química , Oxigênio/química , Catálise , Condutividade Elétrica , Técnicas Eletroquímicas , Porosidade
10.
Acta cir. bras ; 32(12): 1064-1074, Dec. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-886190

RESUMO

Abstract Purpose: To investigate tibial tunnel widening and knee instability after ACL reconstruction with hamstring autograft or irradiated soft tissue allograft. Methods: Eight-two patients were divided into two groups: autograft group and allograft group. Radiographic and clinical evaluations were performed. Results: Seventy patients were followed up with median of 36.3 months (range 36-38 months). Tibial tunnel widening was at or greater than 30% for nine patients in the autograft group and 15 patients in the allograft group (P = 0.0417). The average percentage of tibial tunnel widening was 26.7 ± 4.0 % and 29.7 ± 5.3 % in autograft and allograft groups, respectively (P = 0.0090). Knee range of motion was not affected by the reconstruction operation or different grafts. Thigh atrophy improved significantly within 24 months after ACL reconstructions in both groups. ACL reconstruction with the allograft leaded to less knee stability than that with the autograft from one year after operation (P = 0.0023). There was no significant difference between two groups with respect to Lysholm score (P = 0.1925) and Tegner score (P =0 .0918) at the final follow-up. Conclusion: The allograft group reported significantly more tibial tunnel widening and knee instability compared with the autograft group.


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Adulto Jovem , Tíbia/cirurgia , Reconstrução do Ligamento Cruzado Anterior/métodos , Lesões do Ligamento Cruzado Anterior/cirurgia , Instabilidade Articular/cirurgia , Osteotomia/métodos , Período Pós-Operatório , Coxa da Perna/patologia , Estudos Prospectivos , Seguimentos , Resultado do Tratamento , Período Pré-Operatório , Reconstrução do Ligamento Cruzado Anterior/efeitos adversos , Reconstrução do Ligamento Cruzado Anterior/reabilitação , Duração da Cirurgia , Aloenxertos/transplante , Autoenxertos/transplante , Tendões dos Músculos Isquiotibiais/transplante
11.
Medicine (Baltimore) ; 96(44): e8411, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29095273

RESUMO

The aim of this study was to investigate the risk factors of wound infection after open reduction and internal fixation of calcaneal fractures.In all, 299 patients with 318 calcaneal fractures who underwent open reduction and internal fixation by a single surgeon were grouped according to different outcomes. We gathered the data on each patient including sex, age, injury mechanism, body mass index (BMI), time to operation, fracture type, associated injuries, treatment course, tourniquet time, blood loss, bone graft (yes or no), diabetes (yes or no), smoking history, and complications. Univariate analysis and multivariable analysis were used to determine the association between risk factors and wound infection.Patients who met the entry criteria included 267 males and 32 females with a mean age of 38.6 years. Among them, 5.3% (n = 17) suffered wound infection, and all of the wounds healed after different treatments. According to the univariate analysis, the patients who developed wound infections were active smokers, more obese (higher BMI), had a longer time from injury to operation, and longer tourniquet time. Multivariate analysis indicated that a higher BMI, delayed operation, and active smoking were independent risk factors for wound infection after open reduction and internal fixation of calcaneal fractures.Patients with calcaneal fractures who were smokers and had a higher BMI had a high risk of wound infections. We suggested that surgeons wait to operate until swellings of the injured foot improved, and we also suggested the operation should be within 14 days after the injury.


Assuntos
Calcâneo/lesões , Fixação Interna de Fraturas/efeitos adversos , Fraturas Ósseas/cirurgia , Redução Aberta/efeitos adversos , Infecção da Ferida Cirúrgica/etiologia , Adulto , Índice de Massa Corporal , Calcâneo/cirurgia , Feminino , Fixação Interna de Fraturas/métodos , Humanos , Masculino , Análise Multivariada , Obesidade/complicações , Redução Aberta/métodos , Estudos Retrospectivos , Fatores de Risco , Fumar/efeitos adversos , Infecção da Ferida Cirúrgica/epidemiologia , Fatores de Tempo , Tempo para o Tratamento , Resultado do Tratamento
12.
Medicine (Baltimore) ; 96(29): e7553, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28723779

RESUMO

The aim of this study was to compare the clinical effect of operative treatment and nonoperative treatment for elderly patients with Sanders II-III calcaneal fractures.The study consisted of 60 patients with Sanders II-III calcaneal fractures who were treated in our institution from January 2007 to April 2012. The clinical effect between the operative treatment group of 32 patients and the nonoperative treatment group of 28 patients was studied. Böhler angle, Gissane angle, subtalar joint motion, calcaneal width, and calcaneal height were measured before and after treatment, and these indexes were also measured on the uninjured foot. All patients were followed-up for at least 2 years, and at the last follow-up, we evaluated foot function that was assessed with the American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot score system. A 10-cm visual analog scale (VAS) was used to measure the degree of pain.Böhler angle, Gissane angle, calcaneal width, and calcaneal height, which were preoperatively and postoperatively measured, had a significant difference in the operative group (P < .001), but there was no significant difference between pretreatment and post-treatment in the nonoperative group. Subtalar joint motion was measured pre-treatment and post-treatment and had a significant difference in the 2 groups. When we compared the values of Böhler angle, Gissane angle, subtalar joint motion, calcaneal width, and calcaneal height between post-treatment and the uninjured foot, there was no significant difference in the operative group, but there was a significant difference in the nonoperative group. The values measured after treatment in the 2 groups had a significant difference. Finally, the AOFAS score in the operative group and the nonoperative group were 83.4 ±â€Š9.7 and 74.7 ±â€Š10.3, respectively, and there was a significant difference (P < .001). Also, the 10-cm VAS had a significant difference between the 2 groups.Good clinical result could be obtained with operative treatment in elderly patients with Sanders II-III calcaneal fractures. Open reduction and internal fixation should be performed if there is no surgical contraindication.


Assuntos
Calcâneo/lesões , Calcâneo/cirurgia , Fraturas Ósseas/cirurgia , Idoso , Avaliação da Deficiência , Feminino , Seguimentos , Fixação Interna de Fraturas , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Dor Pós-Operatória , Amplitude de Movimento Articular , Estudos Retrospectivos , Resultado do Tratamento
13.
Nanotechnology ; 28(36): 365403, 2017 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-28590255

RESUMO

It is highly challenging to explore high-performance bi-functional oxygen electrode catalysts for their practical application in next-generation energy storage and conversion devices. In this work, we synthesize hierarchical N-doped carbon microspheres with porous yolk-shell structure (NCYS) as a metal-free electrocatalyst toward efficient oxygen reduction through a template-free route. The enhanced oxygen reduction performances in both alkaline and acid media profit well from the porous yolk-shell structure as well as abundant nitrogen functional groups. Furthermore, such yolk-shell microspheres can be used as precursor materials to motivate the oxygen reduction activity of oxygen evolution oriented materials to obtain a desirable bi-functional electrocatalyst. To verify its practical utility, Zn-air battery tests are conducted and exhibit satisfactory performance, indicating that this constructed concept for preparation of bi-functional catalyst will afford a promising strategy for exploring novel metal-air battery electrocatalysts.

14.
Oncotarget ; 8(19): 31612-31625, 2017 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-28404942

RESUMO

Ascorbic acid, ß-glycerophosphate, and dexamethasone have been used in osteogenesis differentiation medium for in vitro cell culture, nothing is known for delivering these three bioactive compounds in vivo. In this study, we synthesized a novel bioactive scaffold by combining these three compounds with a lysine diisocyanate-based polyurethane. These bioactive compounds were released from the scaffold during the degradation process. The cell culture showed that the sponge-like structure in the scaffold was critical in providing a large surface area to support cell growth and all degradation products of the polymer were non-toxic. This bioactive scaffold enhanced the bone regeneration as evidenced by increasing the expression of three bone-related genes including collagen type I, Runx-2 and osteocalcin in rabbit bone marrow stem cells (BMSCs) in vitro and in vivo. The osteogenesis differentiation of BMSCs cultured in this bioactive scaffold was similar to that in osteogenesis differentiation medium and more extensive in this bioactive scaffold compared to the scaffold without these three bioactive compounds. These results indicated that the scaffold containing three bioactive compounds was a good osteogenesis differentiation promoter to enhance the osteogenesis differentiation and new bone formation in vivo.


Assuntos
Ácido Ascórbico/administração & dosagem , Regeneração Óssea , Dexametasona/administração & dosagem , Glicerofosfatos/administração & dosagem , Osteogênese/efeitos dos fármacos , Alicerces Teciduais , Animais , Materiais Biocompatíveis , Diferenciação Celular , Células Cultivadas , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Polímeros , Coelhos , Ratos , Engenharia Tecidual , Alicerces Teciduais/química
15.
Medicine (Baltimore) ; 96(17): e6725, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28445289

RESUMO

The association between dietary vitamin K intake and the risk of fractures is controversial. Therefore we perform a meta-analysis of cohort or nested case-control studies to investigate the relationship between dietary vitamin K intake and the risk of fractures. A comprehensive search of PubMed and EMBASE (to July 11, 2016) was performed to identify cohort or nested case-control studies providing quantitative estimates between dietary vitamin K intake and the risk of fractures. Summary relative risk (RRs) with corresponding 95% confidence intervals (CIs) were pooled by using a random-effects model. Four cohort studies and one nested case-control study, with a total of 1114 fractures cases and 80,982 participants, were included in our meta-analysis. Vitamin K intake in all included studies refers exclusively to the intake of phylloquinone (vitamin K1), which is the predominant form of vitamin K in foods. We observed a statistically significant inverse association between dietary vitamin K intake and risk of fractures (highest vs. the lowest intake, RR = 0.78, 95% CI: 0.56-0.99; I = 59.2%, P for heterogeneity = .04). Dose-response analysis indicated that the pooled RR of fracture for an increase of 50 µg dietary vitamin K intake per day was 0.97 (95% CI: 0.95-0.99) without heterogeneity among studies (I = 25.9%, P for heterogeneity = .25). When stratified by follow-up duration, the RR of fracture for dietary vitamin K intake was 0.76 (95% CI: 0.58-0.93) in studies with more than 10 years of follow-up. Our study suggests that higher dietary vitamin K intake may moderately decrease the risk of fractures.


Assuntos
Dieta , Fraturas Ósseas/epidemiologia , Vitamina K , Humanos , Estudos Observacionais como Assunto , Risco
16.
Cell Physiol Biochem ; 41(6): 2161-2170, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28441666

RESUMO

BACKGROUND: miR-124-3p has been reported to be involved in the pathogenesis of many diseases by modulating a variety of signaling pathways. In this study, we aimed to understand the impact of miR-124-3p expression level on the fracture healing in the patients of metaphyseal fracture of distal tibia, who received minimal invasive percutaneous plate osteosynthesis. METHODS: We firstly collected 195 patients of metaphyseal fracture of distal tibia, and the genotype of rs531564 was determined: GG (n=124) and GC+CC (n=71). We collected information of the participants including age, gender, total in-hospital time, smoking and alcohol consumption. Subsequently, we searched the miRNA database online to identify the possible binding sequence of miR-124-3p located within the 3'-UTR of the target gene. We did correlation analysis and luciferase to understand the regulatory relationship between miR-124-3p and BMP6. Meanwhile, we also conducted real time PCR and western blotting analysis to study the mRNA and protein expression level of BMP6 in different genotype groups. We then treated the cells with scramble control, miR-124-3p mimics, BMP6 siRNA and miR-124-3p inhibitors to investigate the influence of miR-124-3p on the expression of BMP6, viability and apoptosis of cells. RESULTS: Total in-hospital time was significantly longer in GC+CC group than GG group. MiR-124-3p was up-regulated in GG group than GC and CC groups. BMP6 was virtual target of miR-124-3p. There existed negative regulatory relationship betweenmiR-124-3p and BMP6. The mRNA and protein expression level of BMP6 decreased in GG group. MiR-124-3p decreased the expression of BMP6. MiR-124-3p negatively interfered with the viability of cells and BMP6 positively interfered with the viability of cells. MiR-124-3p reduced apoptosis and BMP6 promoted apoptosis. CONCLUSION: These data proved the expression of miR-124-3p was associated with the healing of metaphyseal fracture of distal tibia, and could be recognized as a biomarker to predict the healing of metaphyseal fracture of distal tibia.


Assuntos
Proteína Morfogenética Óssea 6/genética , Consolidação da Fratura/genética , Regulação da Expressão Gênica/genética , MicroRNAs/genética , Regiões 3' não Traduzidas , Adulto , Alelos , Antagomirs/metabolismo , Apoptose , Sequência de Bases , Proteína Morfogenética Óssea 6/metabolismo , Linhagem Celular Tumoral , Feminino , Fraturas Ósseas/metabolismo , Fraturas Ósseas/patologia , Genótipo , Humanos , Masculino , MicroRNAs/antagonistas & inibidores , MicroRNAs/metabolismo , Polimorfismo de Nucleotídeo Único , RNA Interferente Pequeno/metabolismo , Alinhamento de Sequência , Tíbia/lesões
17.
ChemSusChem ; 10(7): 1469-1474, 2017 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-28169496

RESUMO

During start-up and shut-down operations of fuel cells, high potential is inevitably experienced at cathode, which leads to the deterioration of the oxygen reduction electrocatalyst. The design of catalysts that can repair themselves under severe conditions has been identified as a primary challenge for fuel cells. Herein, self-supported PdAuCu branched nanostructure is synthesized by a hydrothermal method. By smartly utilizing the high-potential treatment, the activity of PdAuCu is significantly enhanced owing to the synergistic effect between the Pd and CuII generated by such treatment. Moreover, the high activity of PdAuCu can be well maintained by repeating the high-potential treatment. We hence propose this catalyst as a "self-repairing" catalyst in a broad sense.


Assuntos
Cobre/química , Ouro/química , Nanoestruturas/química , Oxigênio/química , Paládio/química , Catálise , Eletroquímica , Eletrodos
18.
J Cell Physiol ; 232(12): 3396-3408, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28059444

RESUMO

Tumor necrosis factor α (TNF-α)-induced osteoclast formation have been demonstrated to play an important role in the pathogenesis of estrogen deficiency-mediated bone loss, but the exact mechanisms by which TNF-α enhanced osteoclast differentiation were not fully elucidated. The class III semaphorins members were critical to regulate bone homeostasis. Here, we identified a novel mechanism whereby TNF-α increasing Semaphorin3D expression contributes to estrogen deficiency-induced osteoporosis. In this study, we found that Semaphorin3D expression was upregulated by TNF-α during the process of RANKL-induced osteoclast differentiation. Inhibition of Semaphorin3D in pre-osteoclasts could attenuate the stimulatory effects of TNF-α on osteoclast proliferation and differentiation. Mechanistically, blocking of the Jun N-terminal kinase (JNK) signaling markedly rescued TNF-α-induced Semaphorin3D expression, suggesting that JNK signaling was involved in the regulation of Semaphorin3D expression by TNF-α. In addition, silencing of Semaphorin3D in vivo could alleviate estrogen deficiency-induced osteoporosis. Our results revealed a novel function for Semaphorin3D and suggested that increased Semaphorin3D may contribute to enhanced bone loss by increased TNF-α in estrogen deficiency-induced osteoporosis. Thus, Semaphorin3D may provide a potential therapeutic target for the treatment of estrogen-deficiency induced osteoporosis.


Assuntos
Estrogênios/metabolismo , Osteoclastos/metabolismo , Osteogênese , Osteoporose/metabolismo , Semaforinas/metabolismo , Transdução de Sinais , Fator de Necrose Tumoral alfa/metabolismo , Animais , Diferenciação Celular , Proliferação de Células , Estrogênios/deficiência , Feminino , MAP Quinase Quinase 4/metabolismo , Camundongos Endogâmicos C57BL , Osteoclastos/citologia , Ovariectomia , Ligante RANK/metabolismo
19.
Nanoscale ; 9(3): 1059-1067, 2017 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-27824190

RESUMO

Nitrogen-doped carbon hollow cubes (NCHCs) are fabricated from biomass l-lysine monohydrochloride via a facile and low-cost NaCl template process, showing efficient bifunctional electrocatalytic activities towards the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). The resultant lysine-derived carbon hollow cubes with hierarchical pores on the wall are conducive to mass transport and high utilization of nitrogen dopant-induced active sites during the electrocatalytic process. When used as electrocatalysts for the ORR, an onset potential of 0.92 V vs. RHE has been achieved for NCHCs. A negative shift of only 61 mV exists in the half-wave potential of NCHCs compared to that of the commercial Pt/C (20 wt%). Moreover, the NCHCs show high activity for the OER comparable to that of commercial RuO2/C (20 wt%). The sustainable conversion of biomass lysine to heteroatom-doped carbon hollow cubes and the recyclability of the NaCl template allow a scalable production and practical application of carbon materials for energy storage and conversion.

20.
Acta Cir Bras ; 32(12): 1064-1074, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29319735

RESUMO

PURPOSE: To investigate tibial tunnel widening and knee instability after ACL reconstruction with hamstring autograft or irradiated soft tissue allograft. METHODS: Eight-two patients were divided into two groups: autograft group and allograft group. Radiographic and clinical evaluations were performed. RESULTS: Seventy patients were followed up with median of 36.3 months (range 36-38 months). Tibial tunnel widening was at or greater than 30% for nine patients in the autograft group and 15 patients in the allograft group (P = 0.0417). The average percentage of tibial tunnel widening was 26.7 ± 4.0 % and 29.7 ± 5.3 % in autograft and allograft groups, respectively (P = 0.0090). Knee range of motion was not affected by the reconstruction operation or different grafts. Thigh atrophy improved significantly within 24 months after ACL reconstructions in both groups. ACL reconstruction with the allograft leaded to less knee stability than that with the autograft from one year after operation (P = 0.0023). There was no significant difference between two groups with respect to Lysholm score (P = 0.1925) and Tegner score (P =0 .0918) at the final follow-up. CONCLUSION: The allograft group reported significantly more tibial tunnel widening and knee instability compared with the autograft group.


Assuntos
Lesões do Ligamento Cruzado Anterior/cirurgia , Reconstrução do Ligamento Cruzado Anterior/métodos , Instabilidade Articular/cirurgia , Tíbia/cirurgia , Adolescente , Adulto , Aloenxertos/transplante , Reconstrução do Ligamento Cruzado Anterior/efeitos adversos , Reconstrução do Ligamento Cruzado Anterior/reabilitação , Autoenxertos/transplante , Feminino , Seguimentos , Tendões dos Músculos Isquiotibiais/transplante , Humanos , Masculino , Duração da Cirurgia , Osteotomia/métodos , Período Pós-Operatório , Período Pré-Operatório , Estudos Prospectivos , Coxa da Perna/patologia , Resultado do Tratamento , Adulto Jovem
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