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The cycle stability of lithium metal anode (LMA) largely depends on solid-electrolyte interphase (SEI). Electrolyte engineering is a common strategy to adjust SEI properties, yet understanding its impact is challenging due to limited knowledge on ultrafine SEI structures. Herein, using cryogenic transmission electron microscopy, we reveal the atomic-level SEI structure of LMA in ether-based electrolytes, focusing on the role of LiNO3 additives in SEI modulation at different temperature (25 and 50 °C). Poor cycle stability of LMA in the baseline electrolyte without LiNO3 additives stems from the Li2CO3-rich mosaic-type SEI. Increased LiNO3 content and elevated operating temperature enhance cyclic performance by forming bilayer or multilayer SEI structures via preferential LiNO3 decomposition, but may thicken the SEI, leading to reduced initial Coulombic efficiency and increased overpotential. The optimal SEI features a multilayer structure with Li2O-rich inner layer and closely packed grains in the outer layer, minimizing electrolyte decomposition or corrosion.
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Anion-exchange membrane fuel cells (AEMFCs) are promising alternative hydrogen conversion devices. However, the sluggish kinetics of the hydrogen oxidation reaction in alkaline media hinders further development of AEMFCs. As a synthesis method commonly used to prepare disordered PtRu alloys, the impregnation process is ingeniously designed herein to synthesize sub-3 nm Pt@Ru core-shell nanoparticles by sequentially reducing Pt and Ru at different annealing temperatures. This method avoids complex procedures and synthesis conditions for organic synthesis systems, and the atomic structure evolution of the synthesized core-shell nanoparticles can be tracked. The synthesized Pt@Ru electrocatalyst shows an ultrasmall average size of â¼2.5 nm and thereby a large electrochemical surface area (ECSA) of 166.66 m2 gPt+Ru-1. Exchange current densities (j0) normalized to the mass (Pt + Ru) and ECSA of this electrocatalyst are 8.0 and 5.8 times as high as those of commercial Pt/C, respectively. To the best of our knowledge, the achieved mass-normalized j0 measured by rotating disk electrodes is the highest reported so far. The membrane electrode assembly test of the Pt@Ru electrocatalyst shows a peak power density of 1.78 W cm-2 (0.152 mgPt+Ru cmanode-2), which is higher than that of commercial PtRu/C (1.62 W cm-2, 0.211 mgPt+Ru cmanode-2). The improvement of the intrinsic activity can be attributed to the electron transfer from the Ru shell to the Pt core, and the ultrafine particles further enhance the mass activity. This work reveals the feasibility of using simple impregnation to synthesize fine core-shell nanocatalysts and the importance of investigating the atomic structure of PtRu nanoparticles and other disordered alloys.
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High-concentrated non-flammable electrolytes (HCNFE) in lithium metal batteries prevent thermal runaway accidents, but the microstructure of their solid electrolyte interphase (SEI) remains largely unexplored, due to the lack of direct imaging tools. Herein, cryo-HRTEM is applied to directly visualize the native state of SEI at the atomic scale. In HCNFE, SEI has a uniform laminated crystalline-amorphous structure that can prevent further reaction between the electrolyte and lithium. The inorganic SEI component, Li2 S2 O7 , is precisely identified by cryo-HRTEM. Density functional theory (DFT) calculations demonstrate that the final Li2 S2 O7 phase has suitable natural transmission channels for Li-ion diffusion and excellent ionic conductivity of 1.2 × 10-5 S cm-1 .
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OBJECTIVES: To compare prostate-specific membrane antigen (PSMA) PET with multiparametric MRI (mpMRI) in the diagnosis of pretreatment prostate cancer (PCa). METHODS: Pubmed, Embase, Medline, Web of Science, and Cochrane Library were searched for eligible studies published before June 22, 2022. We assessed risk of bias and applicability by using QUADAS-2 tool. Data synthesis was performed with Stata 17.0 software, using the "midas" and "meqrlogit" packages. RESULTS: We included 29 articles focusing on primary cancer detection, 18 articles about primary staging, and two articles containing them both. For PSMA PET versus mpMRI in primary PCa detection, sensitivities and specificities in the per-patient analysis were 0.90 and 0.84 (p<0.0001), and 0.66 and 0.60 (p <0.0001), and in the per-lesion analysis they were 0.79 and 0.78 (p <0.0001), and 0.84 and 0.82 (p <0.0001). For the per-patient analysis of PSMA PET versus mpMRI in primary staging, sensitivities and specificities in extracapsular extension detection were 0.59 and 0.66 (p =0.005), and 0.79 and 0.76 (p =0.0074), and in seminal vesicle infiltration (SVI) detection they were 0.51 and 0.60 (p =0.0008), and 0.93 and 0.96 (p =0.0092). For PSMA PET versus mpMRI in lymph node metastasis (LNM) detection, sensitivities and specificities in the per-patient analysis were 0.68 and 0.46 (p <0.0001), and 0.91 and 0.90 (p =0.81), and in the per-lesion analysis they were 0.67 and 0.36 (p <0.0001), and 0.99 and 0.99 (p =0.18). CONCLUSION: PSMA PET has higher diagnostic value than mpMRI in the detection of primary PCa. Regarding the primary staging, mpMRI has potential advantages in SVI detection, while PSMA PET has relative advantages in LNM detection. CLINICAL RELEVANCE STATEMENT: The integration of prostate-specific membrane antigen (PSMA) PET into the diagnostic pathway may be helpful for improving the accuracy of prostate cancer detection. However, further studies are needed to address the cost implications and evaluate its utility in specific patient populations or clinical scenarios. Moreover, we recommend the combination of PSMA PET and mpMRI for cancer staging. KEY POINTS: ⢠Prostate-specific membrane antigen PET has higher sensitivity and specificity for primary tumor detection in prostate cancer compared to multiparametric MRI. ⢠Prostate-specific membrane antigen PET also has significantly better sensitivity and specificity for lymph node metastases of prostate cancer compared to multiparametric MRI. ⢠Multiparametric MRI has better accuracy for extracapsular extension and seminal vesicle infiltration compared to ate-specific membrane antigen PET.
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Rechargeable solid-state Na metal batteries (SSNMB) can offer high operational safety and energy density. However, poor solid-solid contact between the electrodes and the electrolyte can dramatically increase interfacial resistance and Na dendrite formation, even at low current rates. Therefore, we developed a carbon-fiber-supported liquid Na-K alloy anode that ensures close anode-electrolyte contact, enabling superior cycle stability and rate capability. We then demonstrated the first cryogenic transmission electron microscopy (cryo-TEM) characterization of an SSNMB, capturing the evolution of solid-electrolyte interphase (SEI) and revealing both crystalline and amorphous phases, which could facilitate ion transport and prevent continuous side reactions. By enhancing contact between the Na-K alloy and solid-state electrolyte, these symmetric cells are capable of cycling for over 800 h without notable increased polarization and enable an unprecedented critical current density (CCD) at 40 mA cm-2. Our liquid Na-K alloy approach offers a promising strategic avenue toward commercial SSNMBs.
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Electrochemical nitrate reduction has become an appealing "waste-to-wealth" approach for sustainable NH3 synthesis owing to its mild operating conditions. However, developing catalysts with high activities and Faradaic efficiencies for this complicated eight-electron reaction is a great challenge. Herein, bismuth ferrite (BiFeO3) flakes, with a distorted perovskite-type structure, are demonstrated to be excellent catalysts for electrochemical NH3 synthesis via nitrate reduction, with a maximum Faradaic efficiency of 96.85%, NH3 yield of 90.45 mg h-1 mgcat-1, at -0.6 V vs. reversible hydrogen electrode. During the nitrate reduction reaction, the crystalline BiFeO3 rapidly converts into an amorphous phase, which is stable in the long term reaction. These results open a new window for rational design of more active and durable electrocatalysts.
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The high specific capacity of alkalic metal (Li, Na, and K) anodes has drawn widespread interest; however, the practical applications of alkalic metal anodes have been hampered by dendrite growth and interfacial instability, resulting in performance deterioration and even safety issues. Here, we describe a simple method for building tunable fluoride-based artificial solid-electrolyte interphase (SEI) from the fluorination reaction of alkali metals with a mild organic fluorinating reagent. Comprehensive characterization by advanced electron microscopes shows that the LiF-based artificial SEI adopts a crystal-glass structure, which enables efficient Li ion transport and improves structural integrity against the volume changes that occur during Li plating/stripping. Compared with bare Li anode, the ones with artificial SEI exhibit decreased voltage hysteresis, enhanced rate capability, and prolonged cycle life. This method is also applied to generate fluoride-based artificial SEI on Na and K metal anodes that brings significant improvement in battery performance.
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Fluoruros , Halogenación , Electrodos , Interfase , Litio/química , Sodio/químicaRESUMEN
A stable solid electrolyte interphase (SEI) layer is crucial for lithium metal anode (LMA) to survive in long-term cycling. However, chaotic structures and chemical inhomogeneity of natural SEI make LMA suffering from exasperating dendrite growth and severe electrode pulverization, which hinder the practical application of LMAs. Here, we design a catalyst-derived artificial SEI layer with an ordered polyamide-lithium hydroxide (PA-LiOH) bi-phase structure to modulate ion transport and enable dendrite-free Li deposition. The PA-LiOH layer can substantially suppress the volume changes of LMA during Li plating/stripping cycles, as well as alleviate the parasitic reactions between LMA and electrolyte. The optimized LMAs demonstrate excellent stability in Li plating/stripping cycles for over 1000â hours at an ultra-high current density of 20â mA cm-2 in Li||Li symmetric cells. A high coulombic efficiency up to 99.2 % in Li half cells in additive-free electrolytes is achieved even after 500â cycles at a current density of 1â mA cm-2 with a capacity of 1â mAh cm-2 .
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Aprotic lithium-oxygen batteries (LOBs) are promising energy storage systems characterized by ultrahigh theoretical energy density. Extensive research has been devoted to this battery technology, yet the detailed operational mechanisms involved, particularly unambiguous identification of various discharge products and their specific distributions, are still unknown or are subjects of controversy. This is partly because of the intrinsic complexity of the battery chemistry but also because of the lack of atomic-level insight into the oxygen electrodes acquired via reliable techniques. In the current study, it is demonstrated that electron beam irradiation could induce crystallization of amorphous discharge products. Cryogenic conditions and a low beam dosage have to be used for reliable transmission electron microscopy (TEM) characterization. High-resolution cryo-TEM and electron energy loss spectroscopy (EELS) analysis of toroidal discharge particles unambiguously identified the discharge products as a dominating amorphous LiO2 phase with only a small amount of nanocrystalline Li2O2 islands dispersed in it. In addition, uniform mixing of carbon-containing byproducts is identified in the discharge particles with cryo-EELS, which leads to a slightly higher charging potential. The discharge products can be reversibly cycled, with no visible residue after full recharge. We believe that the amorphous superoxide dominating discharge particles can lead researchers to reconsider the chemistry of LOBs and pay special attention to exclude beam-induced artifacts in traditional TEM characterizations.
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Polyphyllin I (PPI) is a famous traditional medicine ingredient, which has been explored in wide range of areas. Nevertheless, whether PPI exerts any functions in coronary artery disease (CAD) is still uncertified. Herein, we probed the effect and mechanism of PPI on lipid metabolism and myocardial dysfunction in myocardial cells and CAD rat model. Hypoxia/reoxygenation (H/R)-treated H9c2 cells model was constructed for the in vitro experiments, and CAD model in vivo was established by high-fat feeding. After management with PPI, the correlated factors of lipid metabolism and myocardial function were investigated. The apoptosis of myocardial cells was assessed by Annexin V-FITC/PI kit and TUNEL staining. The apoptosis-associated factors (caspase 3, cleaved caspase 3, Bax, and Bcl-2) were tested by Western blot analysis. The MEK/ERK inhibitor was applied and the functions of MEK/ERK pathway in myocardial damage were investigated. H/R-treated H9c2 cells model was constructed for the in vitro experiments, and CAD model in vivo was established by high-fat feeding. After management with PPI, the correlated factors of lipid metabolism and myocardial function were investigated. The apoptosis of myocardial cells was assessed by Annexin V-FITC/PI kit and TUNEL staining. The apoptosis-associated factors (caspase 3, cleaved caspase 3, Bax, and Bcl-2) were tested by Western blot analysis. The MEK/ERK inhibitor was applied and the functions of MEK/ERK pathway in myocardial damage were investigated. PPI improved lipid metabolism disorder in H/R-induced H9c2 cells or in CAD rat model. Additionally, PPI attenuated myocardial dysfunction in CAD rats via enhancing left ventricular systolic pressure, maximum rate of change of left ventricular pressure (±dp/dtmax ), and arterial blood flow (CF). The apoptosis of myocardial cells was lessened by PPI management, which was further verified by reducing Bax and cleaved caspase 3 expression. Furthermore, PD0325901 (MEK/ERK inhibitor) weakened the effect of PPI on myocardial dysfunction, lipid metabolism, and myocardial cell apoptosis in CAD rats. The research confirmed the protective effect of PPI on myocardial damage in CAD, which was regulated by MEK/ERK pathway.
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Enfermedad de la Arteria Coronaria , Ratas , Animales , Caspasa 3/metabolismo , Proteína X Asociada a bcl-2/metabolismo , Enfermedad de la Arteria Coronaria/tratamiento farmacológico , Enfermedad de la Arteria Coronaria/metabolismo , Metabolismo de los Lípidos , Apoptosis , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Miocitos Cardíacos/metabolismo , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Quinasas de Proteína Quinasa Activadas por Mitógenos/farmacologíaRESUMEN
BACKGROUND: The rat sciatic nerve crush injury model is one of the most commonly used models to research peripheral nerve injury (PNI), however, the evaluation of the model preparation lacks exact standards. This study aimed to investigate accurately assessment methods for research concerning the rat sciatic nerve crush injury. METHODS: The sciatic nerve crush injury model of was performed using the FST toothless forceps. The corresponding locations and pressures of different ratchet strengths were assessed by using CMAP, behavioral, and morphological methods. RESULTS: In each group of PNI, motor and sensory functions were gradually restricted on the injured side of rats as the applied pressure increased. CMAP was more sensitive to nerve injury arising out of the force values obtained from the forceps. CONCLUSIONS: As a sensitive indicator for PNI, the neuroelectrophysiological examination was more likely to reflect the morphological changes of injured nerves. These findings may provide a standardized approach to sciatic crush injury modelling.
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Lesiones por Aplastamiento , Traumatismos de los Nervios Periféricos , Neuropatía Ciática , Animales , Ratas , Nervio Ciático/lesionesRESUMEN
Layered sodium manganese-based oxides are appealing cathode candidates due to their high capacity and cost-effectiveness, yet performance degradation related with unwanted structural evolution still remains a disturbing disadvantage. Herein, atomic resolution STEM (scanning transmission electron microscopy) images of Na-extracted Na2/3NixCo1/3-xMn2/3O2 (x = 0, 1/6, 1/3) are collected and analyzed, to decipher the effect of cobalt and nickel substitution on the structural integrity of layered manganese-based oxides. Cobalt substitution is demonstrated to alleviate the lattice stress and retain the layered structure after sodium removal, and only a local P2-to-O2 phase transition could be identified. By contrast, various types of defects and phase transformation, including rarely reported P2-to-O3, are discovered in the Ni-substituted oxides. The generation of spinel and rock-salt phases is the critical evidence of cation mixing that leads to unrecoverable capacity loss. The interplay of different transition metals is complex, and compositional optimization is encouraged to minimize the effect of the concomitant phase transition.
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BACKGROUND: Previous studies showed that GTS-21, a selective alpha 7 nAchR agonist, can trigger anti-inflammatory effects and improve the survival of septic animals. However, whether GTS-21 affects autophagy responses remains unclear. Here, we tested the hypothesis that GTS-21 ameliorates sepsis-induced hepatic injury by modulating autophagy in mice. METHOD: C57BL/6 male mice were randomly separated and categorized into four groups: the sham group, and CLP group subjected to caecal ligation and puncture (CLP, a model of polymicrobial sepsis). The CLP + GTS-21 group was administered GTS-21 immediately after CLP challenge. α-Bungarotoxin (an alpha 7 nAchR antagonist) was injected before CLP was performed, and then, after CLP challenge, GTS-21 was administered to α-BGT + CLP + GTS-21 group. The hepatic tissue and blood samples were harvested 6 h after the operation. RESULTS: CLP challenge increased TNF-α and IL-6 production, and hepatic enzyme alanine aminotransferase and aspartate transaminase levels. CLP also elevated the expression of hepatic LC3-II, sequestosome-1/p62, Atg7 and Atg5. The administration of GTS-21 inhibited pro-inflammatory cytokine production and hepatic enzymatic marker expression, promoted the expression of LC3-II, Atg7, Atg5, and decreased the expression of p62, which could be reversed by α-BGT treatment. CONCLUSION: Our findings suggested that α7nAchR is involved in diminishing hepatic damage by inhibiting inflammatory responses and improving autophagy in mice with polymicrobial sepsis.
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Autofagia/efectos de los fármacos , Compuestos de Bencilideno/farmacología , Hepatopatías/tratamiento farmacológico , Hepatopatías/metabolismo , Piridinas/farmacología , Sepsis/tratamiento farmacológico , Sepsis/metabolismo , Receptor Nicotínico de Acetilcolina alfa 7/metabolismo , Alanina Transaminasa/metabolismo , Animales , Aspartato Aminotransferasas/metabolismo , Citocinas/metabolismo , Modelos Animales de Enfermedad , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Interleucina-6/metabolismo , Hígado/efectos de los fármacos , Hígado/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
BACKGROUND: Alanine aminotransferase (ALT) is referred as liver transaminase and predominantly expressed by hepatocytes. Previous evidences showed that high levels of ALT were reversely associated with short- and long-term outcomes in patients with myocardial infarction. Besides, low lymphocyte has been demonstrated to be significantly correlated with adverse clinical outcomes in coronary artery disease (CAD). However, evidences about the relationship between ALT-to-lymphocyte ratio (ALR) and outcomes in CAD patients with normal liver function are limited. The aim of this study was to assess the relationship between ALR and clinical outcomes in patients with CAD. METHODS: This is a retrospective cohort study, and a total of 3561 patients were enrolled in Clinical Outcomes and Risk Factors of Patients with CAD after percutaneous coronary intervention (PCI), from January 2013 to December 2017. After excluding patients with liver dysfunction, we finally enrolled 2714 patients. These patients were divided into two groups according to ALR value: the lower group (ALR < 14.06, n = 1804) and the higher group (ALR ≥ 14.06, n = 910). The average follow-up time was 37.59 ± 22.24 months. RESULTS: We found that there were significant differences between the two groups in the incidence of all-cause mortality (ACM) (P < 0.001) and cardiac mortality (CM) (P=0.010). Kaplan-Meier survival analysis suggested that CAD patients with higher ALR tended to have an increased accumulated risk of ACM and CM (log rank P < 0.001 and P=0.006, respectively). Multivariate Cox regression analysis showed that ALR was an independent predictor of ACM (hazard ratio (HR) = 2.017 (95% confidence interval (CI): 1.289-3.158), P=0.002) and CM (HR = 1.862 (95% CI: 1.047-3.313), P=0.034). We did not find significant difference in the incidence of major adverse cardiovascular events (MACEs) and major adverse cardiovascular and cerebrovascular events (MACCEs) between the two groups after adjustments of confounders. CONCLUSION: Our results indicate that ALR is an independent predictor of long-term adverse outcomes in CAD patients who underwent PCI.
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Alanina Transaminasa/sangre , Enfermedad de la Arteria Coronaria/sangre , Enfermedad de la Arteria Coronaria/mortalidad , Recuento de Linfocitos , Intervención Coronaria Percutánea , Anciano , Enfermedad de la Arteria Coronaria/cirugía , Femenino , Humanos , Estimación de Kaplan-Meier , Hígado , Masculino , Persona de Mediana Edad , Análisis Multivariante , Valor Predictivo de las Pruebas , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Factores de Riesgo , Tasa de SupervivenciaRESUMEN
The endoplasmic reticulum (ER) stress plays an important role in myocardial ischemia/reperfusion (MI/R) injury. SERP1, the stress-associated endoplasmic reticulum protein 1, is involved in regulating ER stress response. However, whether it associates with MI/R injury is not identified. Here, we show that SERP1 is induced in the mouse heart after MI/R injury as well as in H9c2 cells under hypoxia/reoxygenation (H/R) treatment. Additionally, SERP1 overexpression reduces H/R-induced H9c2 apoptosis. Moreover, SERP1 overexpression suppresses H/R-induced ER stress and activates JAK2/STAT3 pathway. Furthermore, JAK2/STAT3 pathway inhibition by the specific inhibitor JSI-124 minimizes the suppressive effect of SERP1 overexpression on H/R-induced ER stress and H9c2 apoptosis. Together, these results uncover the protection of SERP1 against H/R-induced H9c2 apoptosis and further relate it to JAK2/STAT3 pathway-dependent attenuation of ER stress. This study suggests SERP1 as a potential regulator invovled in the pathophysiology of MI/R injury.
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Apoptosis , Estrés del Retículo Endoplásmico , Hipoxia , Janus Quinasa 2/metabolismo , Proteínas de la Membrana/metabolismo , Oxígeno/metabolismo , Factor de Transcripción STAT3/metabolismo , Animales , Células Cultivadas , Masculino , Ratones , Ratones Endogámicos C57BL , Daño por Reperfusión Miocárdica/metabolismoRESUMEN
BACKGROUND: It has been confirmed that the triglyceride to high-density lipoprotein cholesterol ratio (THR) is associated with insulin resistance and metabolic syndrome. However, to the best of our knowledge, only a few studies with small sample sizes have investigated the relationship between THR and coronary artery disease (CAD). Therefore, we aimed to assess the correlation between the THR and long-term mortality in patients with CAD after undergoing percutaneous coronary intervention (PCI) in our study that enrolled a large number of patients. METHODS: A total of 3269 post-PCI patients with CAD were enrolled in the CORFCHD-ZZ study from January 2013 to December 2017. The mean follow-up time was 37.59 ± 22.24 months. Patients were divided into two groups according to their THR value: the lower group (THR < 2.84, n = 1232) and the higher group (THR ≥ 2.84, n = 2037). The primary endpoint was long-term mortality, including all-cause mortality (ACM) and cardiac mortality (CM). The secondary endpoints were major adverse cardiac events (MACEs) and major adverse cardiac and cerebrovascular events (MACCEs). RESULTS: In our study, ACM occurred in 124 patients: 30 (2.4%) in the lower group and 94 (4.6%) in the higher group (P = 0.002). MACEs occurred in 362 patients: 111 (9.0%) in the lower group and 251 (12.3%) in the higher group (P = 0.003). The number of MACCEs was 482: 152 (12.3%) in the lower group and 320 (15.7%) in the higher group (P = 0.008). Heart failure occurred in 514 patients: 89 (7.2%) in the lower group and 425 (20.9%) in the higher group (P < 0.001). Kaplan-Meier analyses showed that elevated THR was significantly related to long-term ACM (log-rank, P = 0.044) and the occurrence of heart failure (log-rank, P < 0.001). Multivariate Cox regression analyses showed that the THR was an independent predictor of long-term ACM (adjusted HR = 2.042 [1.264-3.300], P = 0.004) and heart failure (adjusted HR = 1.700 [1.347-2.147], P < 0.001). CONCLUSIONS: An increased THR is an independent predictor of long-term ACM and heart failure in post-PCI patients with CAD.
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HDL-Colesterol/sangre , Enfermedad Coronaria/diagnóstico , Insuficiencia Cardíaca/diagnóstico , Intervención Coronaria Percutánea , Triglicéridos/sangre , Anciano , Biomarcadores/sangre , LDL-Colesterol/sangre , Enfermedad Coronaria/sangre , Enfermedad Coronaria/mortalidad , Femenino , Insuficiencia Cardíaca/sangre , Insuficiencia Cardíaca/mortalidad , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Análisis Multivariante , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Factores de Riesgo , Resultado del TratamientoRESUMEN
Carbon-supported nickel selenide (Ni0.85 Se/C) hollow nanowires are prepared from carbon-coated selenium nanowires via a self-templating hydrothermal method, by first dissolving selenium in the Se/C nanowires in hydrazine, allowing it to diffuse out of the carbon layer, and then reacting with nickel ions into Ni0.85 Se nanoplates on the outer surface of the carbon. Ni0.85 Se/C hollow nanowires are employed as anode materials for sodium-ion batteries, and their electrochemical performance is evaluated via the cyclic voltammetry and electrochemical impedance spectroscopy combined with ex situ X-ray photoelectron spectroscopy and X-ray diffraction measurements. It is found that Ni0.85 Se/C hollow nanowires exhibit greatly enhanced cycle stability and rate capability as compared to Ni0.85 Se nanoparticles, with a reversible capacity around 390 mA h g-1 (the theoretical capacity is 416 mA h g-1 ) at the rate of 0.2 C and 97% capacity retention after 100 cycles. When the current rate is raised to 5 C, they still deliver capacity of 219 mA h g-1 . The synthetic methodology introduced here is general and can easily be applied to building similar structures for other metal selenides in the future.
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OBJECTIVE: To investigate the regulatory mechanism of the c-Jun N-terminal protein kinase (JNK) signaling pathway in substantia nigra (SN) dopaminergic neurons inflammation and apoptosis, and the neuroprotective effect of Zishenpingchan granules in mice with Parkinson's disease (PD) induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). METHODS: PD model mice were established by intraperitoneally injecting MPTP. Sixty mice were divided into a model group, Traditional Chinese Medicine (TCM) group and control group. The mice of the TCM group were administered Zishenpingchan granules 7 days before PD induction. Seven days after PD induction, we examined locomotor activity, and performed the rotarod test and swimming test, to evaluate limb movement function. Furthermore, we used immunohistochemistry and western blotting to examine the expression of tyrosine hydroxylase (TH), cyclooxygenase-2 (Cox-2), caspase-3 and p-JNK. The terminal deoxynucleotidyl transferase mediated dUTP nick end labeling (TUNEL) method was used to examine neuron apoptosis in the SN. RESULTS: Compared with the control group, the mean score of locomotor activity, rotarod test and swimming test was significantly lower in the model group (P < 0.05); the TH-positive neuron expression was significantly decreased in the SN pars compacta (SNpc); the protein expression levels of Cox-2, caspase-3 and p-JNK was obviously increased; and the number of TUNEL-positive neurons in the SN was increased (P < 0.01). Compared with the model group, the mean score of neurobehavioral tests in the TCM group was obviously higher, the loss of TH-positive neurons ignificantly decreased, the protein expression levels of Cox-2, caspase-3 and p-JNK obviously decreased, and the number of TUNEL- positive neurons in the SN clearly decreased (P < 0.01). CONCLUSION: The JNK pathway plays an important role in the regulation of inflammation and apoptosis in nigral cells in PD mice. TCM can suppress the over-activation of the JNK pathway in the SN, and alleviate the inflammatory response in nigral cells and dopaminergic neuron apoptosis in PD mice.
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Medicamentos Herbarios Chinos/administración & dosificación , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Fármacos Neuroprotectores/administración & dosificación , Enfermedad de Parkinson/tratamiento farmacológico , 1-Metil-4-fenil-1,2,3,6-Tetrahidropiridina/efectos adversos , Animales , Apoptosis/efectos de los fármacos , Ciclooxigenasa 2/genética , Ciclooxigenasa 2/metabolismo , Modelos Animales de Enfermedad , Dopamina/metabolismo , Humanos , Proteínas Quinasas JNK Activadas por Mitógenos/genética , Masculino , Ratones , Ratones Endogámicos C57BL , Enfermedad de Parkinson/enzimología , Enfermedad de Parkinson/genética , Enfermedad de Parkinson/metabolismo , Transducción de Señal/efectos de los fármacos , Sustancia Negra/enzimología , Sustancia Negra/metabolismo , Tirosina 3-Monooxigenasa/genética , Tirosina 3-Monooxigenasa/metabolismoRESUMEN
BACKGROUND: To investigate the impact of professional physician-coordinated intensive follow-up on long-term expenditures after percutaneous coronary intervention (PCI) in unstable angina (UA) patients. METHODS: In this study, there were 669 UA patients who underwent successful PCI and followed up for 3 years, then divided into the intensive follow-up group (N = 337), and the usual follow-up group (N = 332). Patients were provided with detailed discharge information and individualized follow-up schedules. The intensive group received the extra follow-up times and medical consultations, and all patients were followed up for approximately 3 years. RESULTS: At the 3-year mark after PCI, the cumulative major adverse cardiac events (MACE), recurrence of myocardial ischemia, cardiac death, all-cause death and revascularization in the intensive group were lower than in the usual group. Additionally, the proportion of good medication adherence was significantly higher than in the usual group (56.4% vs. 46.1%, p < 0.001). The hospitalization daytime, total hospitalization cost and total medical cost in the intensive group were lower. Multiple linear regression showed that diabetes, hypertension, intensive follow-up and good medication adherence were associated with emergency and regular clinical cost (p < 0.05), the re-hospitalization cost (p < 0.05) and the total medical cost (p < 0.05) of patient care. Intensive follow-up and good adherence were negatively correlated with the cost of re-hospitalization (standardized coefficients = -0.132, -0.128, p < 0.05) and total medical costs (standardized coefficients = -0.072, -0.086, p < 0.05). CONCLUSIONS: Intensive follow-up can reduce MACE, improve medication adherence and save long-term total medical costs, just by increasing the emergency and regular clinical visits cost in UA patients after PCI.
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MicroRNAs (miRNAs) are a new class of prognostic and diagnostic biomarkers for many cancers. Recent studies have shown that miRNAs are highly stable in plasma/serum. The aim of this study was to investigate the role of miR-421 in osteosarcoma. We found that the serum expression levels of miR-421 were significantly higher in osteosarcoma patients than those in healthy volunteers. Moreover, miR-421 expression was significantly higher in osteosarcoma tissues compared with that in the adjacent normal tissues. Meanwhile, the expression of miR-421 was upregulated in 90 % (36/40) osteosarcoma tissues compared to non-tumor tissues. More importantly, the expression levels of miR-421 in osteosarcoma tissues were correlated with those in patients' serum. In addition, patients with high miR-421 expression had shorter overall survival (OS) than those with low expressions. We also found that overexpression of miR-421 promoted osteosarcoma cell line MG-63 proliferation, migration, and invasion. In conclusion, miR-421 expression levels were upregulated in osteosarcoma tissue and serum and it may be a useful marker for diagnosis of osteosarcoma.