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Sodium-ion batteries (SIBs) are experiencing a large-scale renaissance to supplement or replace expensive lithium-ion batteries (LIBs) and low energy density lead-acid batteries in electrical energy storage systems and other applications. In this case, layered oxide materials have become one of the most popular cathode candidates for SIBs because of their low cost and comparatively facile synthesis method. However, the intrinsic shortcomings of layered oxide cathodes, which severely limit their commercialization process, urgently need to be addressed. In this review, inherent challenges associated with layered oxide cathodes for SIBs, such as their irreversible multiphase transition, poor air stability, and low energy density, are systematically summarized and discussed, together with strategies to overcome these dilemmas through bulk phase modulation, surface/interface modification, functional structure manipulation, and cationic and anionic redox optimization. Emphasis is placed on investigating variations in the chemical composition and structural configuration of layered oxide cathodes and how they affect the electrochemical behavior of the cathodes to illustrate how these issues can be addressed. The summary of failure mechanisms and corresponding modification strategies of layered oxide cathodes presented herein provides a valuable reference for scientific and practical issues related to the development of SIBs.
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It remains a tremendous challenge to achieve high-efficiency bifunctional electrocatalysts for both the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER) for hydrogen production by water splitting. Herein, a novel hybrid of 0D nickel nanoparticles dispersed on the one-dimensional (1D) molybdenum carbide micropillars embedded in the carbon layers (Ni/Mo2C@C) was successfully prepared on nickel foam by a facile pyrolysis strategy. During the synthesis process, the nickel nanoparticles and molybdenum carbide were simultaneously generated under H2 and C2H2 mixed atmospheres and conformally encapsulated in the carbon layers. Benefiting from the distinctive 0D/1D heterostructure and the synergistic effect of the biphasic Mo2C and Ni together with the protective effect of the carbon layer, the reduced activation energy barriers and fast catalytic reaction kinetics can be achieved, resulting in a small overpotential of 96 mV for the HER and 266 mV for the OER at the current density of 10 mA cm-2 together with excellent durability in 1.0 M KOH electrolyte. In addition, using the developed Ni/Mo2C@C as both the cathode and anode, the constructed electrolyzer exhibits a small voltage of 1.55 V for the overall water splitting. The novel designed Ni/Mo2C@C may give inspiration for the development of efficient bifunctional catalysts with low-cost transition metal elements for water splitting.
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OBJECTIVE: To understand the characteristics of malaria prevalence in Sichuan Province from 2012 to 2014, so as to provide evidences for improving the work of malaria elimination. METHODS: The epidemiological data of malaria cases in Sichuan Province were collected from the Disease Surveillance Information Reporting System of Chinese Center for Disease Control and Prevention, and analyzed with the descriptive epidemiological method. RESULTS: A total of 690 imported malaria cases were reported in Sichuan Province from 2012 to 2014. In detail, 54.49% (376/690) were falciparum malaria cases, 42.03% (290/690) were vivax malaria cases, 0.58% (4/690) were malariae malaria cases, 1.88% (13/690) were ovale malaria cases, and 1.01% (7/690) were mixed infection cases with Plasmodium vivax and P. falciparum. Among them, five cases died. Totally 671 malaria cases were infected overseas, accounting for 97.25% of the total cases. Among which, 517 patients returned from Africa and 138 patients returned from Southeast Asia. There were malaria cases reported in the whole year, and 185 cases were reported in May and June, accounting for 26.81% of the total cases. The cases distributed in 20 prefecture-level cities in the whole province, and there were 137 and 105 ones reported in Guangan and Chengdu, respectively, which accounted for 35.07% of the total cases. CONCLUSIONS: The number of patients with overseas imported malaria in Sichuan Province increases year by year, and therefore effective measures should be carried out to control the overseas imported malaria.
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Malária/epidemiologia , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , China/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ocupações/estatística & dados numéricos , Prevalência , Estações do AnoRESUMO
<p><b>OBJECTIVE</b>To research the application and clinical effect of titanium elastic nails (TEN) for the treatment of closed clavicular fracture in elder children.</p><p><b>METHODS</b>From October 2010 to December 2012,16 elderly children with clavicular fracture of elder children were treated with internal fixation, including 9 boys and 7 girls with an average age of 14.2 yeats old ranging from 9 to 17 years. The mean time between injury and surgery was 2 to 6 days. Thirteen patients had a transverse fractures; 3 patients had a oblique fractures, excluding the long-oblique patients. Neer function score after 3 months follow-up and the shoulder activity degree after 3 weeks followed were compared respectively between the injured side and healthy side. Fracture reduction and healing were followed up by X-rays to analyze internal fixation with TEN technique.</p><p><b>RESULTS</b>All patients were healed well after surgery. There were 2 cases with soft tissue irritation. No cases of infection, TEN broken, delayed healing or skin bursting were observed. All patients were followed up for 3 to 10 months,with an average of 7.2 months. There were no significant differences (t=2.12, P>0.05) between the healthy side (98.75±2.70) and injured side(96.69±6.22)of Neer score at 3 months during followed up. The shoulder activity at 3 weeks during followed up was different between both sides (P<0.05). The intramedullary nail was removed after X-rays at 12-18 weeks during followed up showed good bone healing,and the shoulder function was recovered well.</p><p><b>CONCLUSION</b>Internal fixation with TEN for the treatment of clavicular fracture has advantages of a limited invasion, beauty, safety and reliability. This technique provides an ideal fixation option for the treatment of clavicular fracture in elder children.</p>
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Adolescente , Criança , Feminino , Humanos , Masculino , Pinos Ortopédicos , Clavícula , Ferimentos e Lesões , Cirurgia Geral , Elasticidade , Fixação Interna de Fraturas , Métodos , Fraturas Ósseas , Cirurgia Geral , TitânioRESUMO
<p><b>BACKGROUND</b>Small noncoding microRNAs regulate gene expression in cardiac development and disease and have been implicated in the aging process and in the regulation of extracellular matrix proteins. However, their role in age-related cardiac remodeling and atrial fibrillation (AF) was not well understood. The present study was designed to decipher molecular mechanisms underlying age-related atrial structural remodeling and AF.</p><p><b>METHODS</b>Three groups of dogs were studied: adult and aged dogs in sinus rhythm and with persistent AF induced by rapid atrial pacing. The expressions of microRNAs were measured by quantitative real-time polymerase chain reaction. Pathohistological and ultrastructural changes were tested by light and electron microscopy. Apoptosis index of myocytes was detected by TUNEL.</p><p><b>RESULTS</b>Samples of atrial tissue showed the abnormal pathohistological and ultrastructural changes, the accelerated fibrosis, and apoptosis with aging and/or in AF dogs. Compared to the adult group, the expressions of microRNAs-21 and -29 were significantly increased, whereas the expressions of microRNAs-1 and -133 showed obvious downregulation tendency in the aged group. Compared to the aged group, the expressions of microRNAs-1, -21, and -29 was significantly increased in the old group in AF; contrastingly, the expressions of microRNA-133 showed obvious downregulation tendency.</p><p><b>CONCLUSION</b>These multiple aberrantly expressed microRNAs may be responsible for modulating the transition from adaptation to pathological atrial remodeling with aging and/or in AF.</p>
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Animais , Cães , Fatores Etários , Apoptose , Fibrilação Atrial , Remodelamento Atrial , Fator de Crescimento do Tecido Conjuntivo , Fisiologia , Eletrocardiografia , Fibrose , Marcação In Situ das Extremidades Cortadas , MicroRNAs , Fisiologia , Miocárdio , PatologiaRESUMO
<p><b>OBJECTIVE</b>To investigate the association between the KCNE1 gene G38S and the KCNE4 gene E145D and atrial fibrillation in Uygur and Han populations living in Xinjiang.</p><p><b>METHODS</b>KCNE1 gene G38S and the KCNE4 gene E145D genotype and frequency were determined using PCR restriction fragment length polymorphism (PCR-RFLP) in 488 atrial fibrillation patients (237 Uygur and 251 Han residents) and 488 age-and-gender matched controls (237 Uygur and 251 Han residents).</p><p><b>RESULTS</b>Genotype and allele frequency of KCNE1 gene G38S were similar between atrial fibrillation group and control group in the Han population (P = 0.556, P = 0.946). In the Uygur population, there was a statistical difference between atrial fibrillation group and control group (P = 0.018, P = 0.003). Logistic regression analysis revealed the KCNE1 38 G was one of the independent risk factors for atrial fibrillation in the Uygur population (OR = 1.634, 95%CI: 1.192-2.240, P = 0.002). The KCNE4 gene E145D, genotype and allele frequency were significantly different between atrial fibrillation group and control group in the Uygur population and Han population (P = 0.041, P = 0.015;P = 0.032, P = 0.013) . Logistic regression analysis revealed the KCNE4 145D was one of the independent risk factors for atrial fibrillation in the Uygur population and Han population (OR = 1.636, 95%CI:1.173-2.281, P = 0.004; OR = 1.491, 95%CI:1.076-2.065, P = 0.016) .</p><p><b>CONCLUSIONS</b>KCNE1 G38S is not associated with atrial fibrillation in the Han population while the KCNE1 G38S is associated with atrial fibrillation in the Uygur population. KCNE4 gene E145D is associated with atrial fibrillation in both Uygur population and Han population.</p>
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Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Povo Asiático , Genética , Fibrilação Atrial , Etnologia , Genética , Estudos de Casos e Controles , China , Frequência do Gene , Genótipo , Polimorfismo de Nucleotídeo Único , Canais de Potássio de Abertura Dependente da Tensão da Membrana , Genética , Fatores de RiscoRESUMO
<p><b>OBJECTIVE</b>To investigate aging-related ionic remodeling of L-type voltage dependent calcium channel (LVDCC) in left atria of canine.</p><p><b>METHODS</b>Seven adult (2.0 - 2.5 years) and 10 aged (> 8 years) dogs were used. The current of LVDCC was recorded by patch clamp technique in the whole cell mode. The action potential duration (APD(90)), amplitude of action potential plateau (APA), I(Ca-L) peak current density of LVDCC were recorded. The mRNA and protein expressions of α1c subunit (Ca(V1.2)), sarcoplasmic reticulum Ca(2+)-ATPase (SECRA(2)), Calpain-I, ryanodine receptor (RYR(2)) were detected by quantitative RT-PCR and Western blot, respectively.</p><p><b>RESULTS</b>I(Ca-L) peak current density [(-8.11 ± 0.54) pA/pF vs. (-14.04 ± 0.82) pA/pF, P < 0.05] was significantly reduced and action potential duration to 90% repolarization (APD(90)) significantly prolonged [(340.5 ± 10.1) ms vs. (320.0 ± 7.9) ms, P < 0.05] in aged group than in adult group. The mRNA gene expression level of Ca(V1.2) was significantly lower (0.90 ± 0.35 vs. 2.38 ± 0.40, P < 0.05) while mRNA expression of RYR(2) was significantly higher (4.39 ± 4.68 vs. 1.49 ± 1.69, P < 0.05) in the aged dogs than in the adult dogs. mRNA expression of SECRA(2) and Calpain-I was similar between the two groups. Similarly, the protein expression level of Ca(V1.2) was significantly lower (0.13 ± 0.10 vs. 0.29 ± 0.12, P < 0.05) while the protein expression level of RYR(2) was significantly higher (0.18 ± 0.21 vs. 0.08 ± 0.36, P < 0.05) in the aged dogs than in the adult dogs. Again, protein expression of SECRA(2), PLN(1) and Calpain-I was similar between the two groups.</p><p><b>CONCLUSION</b>These data suggest that aging could induce mRNA and protein expression changes of Ca(V1.2) and RYR(2) of LVDCC which might serve as the molecular basis of I(Ca-L) remodeling in aged dogs and might be linked to the increased likelihood of developing atrial fibrillation (AF) in aged dogs.</p>
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Animais , Cães , Potenciais de Ação , Fatores Etários , Fibrilação Atrial , Metabolismo , Canais de Cálcio Tipo L , Metabolismo , Átrios do Coração , Metabolismo , Miócitos Cardíacos , Metabolismo , Técnicas de Patch-Clamp , Canal de Liberação de Cálcio do Receptor de Rianodina , Metabolismo , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático , MetabolismoRESUMO
<p><b>OBJECTIVE</b>To observe the safety and efficacy of implantable cardioverter defibrillator (ICD) intraoperative defibrillation threshold (DFT) measured by defibrillation safety margin (DSM).</p><p><b>METHODS</b>Fifty-two patients underwent ICD implantation were enrolled in this study (25 single chamber ICD, 23 double chamber ICD, 4 three chamber ICD). DFT was measured by DSM method. All patients were followup regularly.</p><p><b>RESULTS</b>DFT was (13.27 ± 2.95) J and DSM was (17.40 ± 2.89) J in this patient cohort. There were no serious intraoperative complications. Malignant ventricular arrhythmia occurred in 38 patients post ICD, 469 episodes of nonsustained ventricular tachycardia (VT) were spontaneously terminated, 265 episodes were sustained VT and 245 (92.5%) episodes were successfully terminated by 1 antitachycardia pace treatment (ATP), 13 (4.89%) episodes successfully terminated by 2 ATP, and ATP failed to terminate VT in 7 (2.64%) episodes and VTs were terminated by low energy cardioversion. All 141 episodes of ventricular fibrillation (VF) were successfully identified, and 14 episodes spontaneously terminated before discharging, 127 VF episodes (91.34%) were terminated by 1 energy shock, defibrillation energy was (12.84 ± 3.18) J, 11 (12.2%) VF episodes were terminated by 2 energy shocks, defibrillation energy was (16.36 ± 2.34) J.</p><p><b>CONCLUSION</b>It is safe and feasible to use defibrillation threshold measured by DSM for patients receiving ICD implantation.</p>
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Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Desfibriladores Implantáveis , Segurança de Equipamentos , Seguimentos , Cuidados Intraoperatórios , Resultado do Tratamento , Fibrilação Ventricular , TerapêuticaRESUMO
The present study aimed to investigate the mRNA expression levels of collagen, matrix metalloproteinases (MMPs), and tissue inhibitors of metalloproteinases (TIMPs) in the left and right atria in patients with chronic atrial fibrillation (CAF). Forty five patients with valvular heart disease were sampled in this study, including 18 patients with sinus rhythm (SR), 27 patients with CAF. Clinical data of these patients were collected, and the left and right atrial appendages were obtained from these patients during heart valvular replacement surgery. The mRNA levels of collagen type I, collagen type III, MMP1, MMP9, TMP1 of the atria were then measured by semi-quantitative RT-PCR. The results obtained were as follows. Compared to those in SR group, in atria of CAF group, the mRNA levels of collagen type I, MMP1 and MMP9 increased (P<0.05), while the mRNA level of TMP1 decreased (P<0.01). There were no significant differences in the mRNA levels of collagen type I, collagen type III, MMP1, MMP9 and TMP1 between the left and right atria of SR group (P>0.05). In CAF group, the mRNA level of MMP1 in the right atrium was higher than that in the left atrium (P<0.05), however, the mRNA level of MMP9 in the left atrium was higher than that in the right atrium (P<0.01). In both the left and right atria, the mRNA of collagen type I was positively correlated with the corresponding atrial diameter; the mRNA of MMP1 and MMP9 was positively correlated with the mRNA of collagen type I, and was negatively correlated with the mRNA of TMP1. These results suggest that the increased level of collagen type I associated with selective upregulation of MMP1, 9 and downregulation of TMP1, 9 in the atrium might be the molecular basis of atrial interstitial fibrosis in patients with CAF. Moreover, during CAF development, there is difference in the expression of MMPs between the left and right atria.
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Idoso , Humanos , Fibrilação Atrial , Colágeno Tipo I , Metabolismo , Colágeno Tipo III , Metabolismo , Átrios do Coração , Metabolismo , Metaloproteinase 1 da Matriz , Metabolismo , Metaloproteinase 9 da Matriz , Metabolismo , RNA Mensageiro , Metabolismo , Inibidor Tecidual de Metaloproteinase-1 , MetabolismoRESUMO
<p><b>OBJECTIVE</b>To discuss the role of calcium-overloading in initiation and maintenance of atrial fibrillation (AF).</p><p><b>METHODS</b>The right atrial appendages were obtained from 14 patients with AF and 12 patients with sinus rhythm. The mRNA expression of proteins influencing the calcium homeostasis was measured by semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) and normalized to the mRNA level of glyceraldehyde-3- phosphate dehydrogenase. The left atrial diameter (LAD), mitral valvular area (MVOA), and systolic pulmonary arterial pressure were obtained by echocardiography before surgery.</p><p><b>RESULTS</b>Compared to sinus rhythm group, the mRNA levels of L-type calcium channel alc, sarcoplasmic reticulum (SR), calcium adenosine triphosphatase (Ca2+ -ATPase), and ryanodine receptor type-2 (R(Y) R2) were significantly decreased (P < 0.01); the mRNA level of inositol triphosphate receptor type-1 (IP3R1) was significantly increased (P < 0.05). No changes in the mRNA expression of phospholamban and calsequestrin were observed between two groups (P > 0.05). Correlations were found between MVOA and mRNA levels of LVDC-Calc, SR Ca2+ -ATPase (r = 0.719, P = 0.004; r = 0.625, P = 0.017). The mRNA level of SR Ca2+ -ATPase was negatively correlated with LAD (r = -0.573, P = 0.032).</p><p><b>CONCLUSIONS</b>Calcium loading may be responsible for the occurrence and maintenance of AF, and abnormal regulation in the mRNA expression may be the molecular mechanism of intracellular Ca2+ overload. The progressive nature of AF involves structural change.</p>
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Humanos , Arritmia Sinusal , Metabolismo , Fibrilação Atrial , Metabolismo , Patologia , Cálcio , Metabolismo , Canais de Cálcio , Genética , Proteínas de Ligação ao Cálcio , Genética , ATPases Transportadoras de Cálcio , Genética , Doença Crônica , Átrios do Coração , Metabolismo , Patologia , Valva Mitral , Patologia , Miocárdio , Metabolismo , RNA MensageiroRESUMO
<p><b>OBJECTIVE</b>To investigate the chemical constituents from Pholidota yunnanensis.</p><p><b>METHOD</b>Various chromatographic techniques were employed for isolation and purification of the constituents. The structures were elucidated by chemical and spectral analyses.</p><p><b>RESULT</b>Seven compounds were obtained and they were identified by spectroscopic analysis as n-nonacosane, cyclopholidone, n-dotriacontanoic acid, n-octacostyl ferulate, cyclopholidonol, cycloneolitsol and beta-sitosterol, respectively.</p><p><b>CONCLUSION</b>n-octacostyl ferulate and cycloneolitsol were isolated from genus Pholidota for the first time.</p>
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Alcanos , Química , Ácidos Cafeicos , Química , Ácidos Graxos , Química , Estrutura Molecular , Orchidaceae , Química , Plantas Medicinais , Química , Esteroides , QuímicaRESUMO
<p><b>AIM</b>To investigate the chemical constituents of Dendrobium fimbriatum Hook.</p><p><b>METHODS</b>Various chromatographic techniques were employed for isolation and purification of the constituents. The structures were elucidated by IR, MS, 1HNMR, 13CNMR and 2D-NMR.</p><p><b>RESULTS</b>Eight compounds were obtained and identified by spectral analysis as fimbriatone, confusarin, crepidatin, physcion, rhein, ayapin, scopolin methyl ether and n-octacostyl ferulate.</p><p><b>CONCLUSION</b>Fimbriatone is a new compound, physcion and rhein are firstly isolated from Genus Dendrobium. The others are found from this species for the first time. Fimbriatone showed potential inhibitory effects on BGC cell line.</p>
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Humanos , Antraquinonas , Química , Antineoplásicos Fitogênicos , Química , Farmacologia , Divisão Celular , Dendrobium , Química , Emodina , Química , Compostos Heterocíclicos de 4 ou mais Anéis , Química , Farmacologia , Lactonas , Química , Farmacologia , Estrutura Molecular , Plantas Medicinais , Química , Neoplasias Gástricas , Patologia , Células Tumorais CultivadasRESUMO
<p><b>OBJECTIVE</b>To identify the botanical origin of the Guijiu in Shosoin of Japan from Tang Dynasty, and trace its medicinal history.</p><p><b>METHOD</b>Anatomical characteristics of the underground parts of Guijiu in Shosoin were compared with those of Hosta plantaginea and H. ventricosa, and research on the medicinal history of Guijiu was made based on its original identification results and describes in herbals.</p><p><b>RESULT AND CONCLUSION</b>Guijiu in Shosoin of Japan was derived from the underground parts of H. plantaginea and is one of Guijiu used in Tang Dynasty and earlier on.</p>