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Understanding the structure-performance relationships of a frustrated Lewis pair (FLP) at the atomic level is key to yielding high efficiency in activating chemically "inert" molecules into value-added products. A sound strategy was developed herein through incorporating oxygen defects into a Zr-based metal-organic layer (Zr-MOL-D) and employing Lewis basic proximal surface hydroxyls for the in situ formation of solid heterogeneous FLP (Zr4-δ-VO-Zr-OH). Zr-MOL-D exhibits a superior CO2 to CO conversion rate of 49.4 µmol g-1 h-1 in water vapor without any sacrificing agent or photosensitizer, which is about 12 times higher than that of pure MOL (Zr-MOL-P), with extreme stability even after being placed for half a year. Theoretical and experimental results reveal that the introduction of FLP converts the process of the crucial intermediate COOH* from an endothermic reaction to an exothermic spontaneous reaction. This work is expected to provide new prospects for developing efficient MOL-based photocatalysts in FLP chemistry through a sound defect-engineering strategy.
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High-entropy oxides (HEOs), featuring infinite chemical composition and exceptional physicochemical properties, are attracting much attention. The configurational entropy caused by a component disorder of HEOs is popularly believed to be the main driving force for thermal stability, while the role of vibrational entropy in the thermodynamic landscape has been neglected. In this study, we systematically investigated the vibrational entropy of multicomponent rutile oxides (including Fe0.5Ta0.5O2, Fe0.333Ti0.333Ta0.333O2, Fe0.25Ti0.25Ta0.25Sn0.25O2, and Fe0.21Ti0.21Ta0.21Sn0.21Ge0.16O2) by precise heat capacity measurements. It is found that vibrational entropy gradually decreases with increasing component disorder, beyond what one could expect from an equilibrium thermodynamics perspective. Moreover, all multicomponent rutile oxides exhibit a positive excess vibrational entropy at 298.15 K. Upon examinations of configuration disorder, size mismatch, phase transition, and polyhedral distortions, we demonstrate that the excess vibrational entropy plays a pivotal role in lowering the crystallization temperature of multicomponent rutile oxides. These findings represent the first experimental confirmation of the role of lattice vibrations in the thermodynamic landscape of rutile HEOs. In particular, vibrational entropy could serve as a novel descriptor to guide the predictive design of multicomponent oxide materials.
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Interfacial interaction dictates the overall catalytic performance and catalytic behavior rules of the composite catalyst. However, understanding of interfacial active sites at the microscopic scale is still limited. Importantly, identifying the dynamic action mechanism of the "real" active site at the interface necessitates nanoscale, high spatial-time-resolved complementary-operando techniques. In this work, a Co3O4 homojunction with a well-defined interface effect is developed as a model system to explore the spatial-correlation dynamic response of the interface toward oxygen evolution reaction. Quasi in situ scanning transmission electron microscopy-electron energy-loss spectroscopy with high spatial resolution visually confirms the size characteristics of the interface effect in the spatial dimension, showing that the activation of active sites originates from strong interfacial electron interactions at a scale of 3 nm. Multiple time-resolved operando spectroscopy techniques explicitly capture dynamic changes in the adsorption behavior for key reaction intermediates. Combined with density functional theory calculations, we reveal that the dynamic adjustment of multiple adsorption configurations of intermediates by highly activated active sites at the interface facilitates the O-O coupling and *OOH deprotonation processes. The dual dynamic regulation mechanism accelerates the kinetics of oxygen evolution and serves as a pivotal factor in promoting the oxygen evolution activity of the composite structure. The resulting composite catalyst (Co-B@Co3O4/Co3O4 NSs) exhibits an approximately 70-fold turnover frequency and 20-fold mass activity than the monomer structure (Co3O4 NSs) and leads to significant activity (η10 â¼257 mV). The visual complementary analysis of multimodal operando/in situ techniques provides us with a powerful platform to advance our fundamental understanding of interfacial structure-activity relationships in composite structured catalysts.
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Iron-based perovskite air electrodes for protonic ceramic cells (PCCs) offer broad application prospects owing to their reasonable thermomechanical compatibility and steam tolerance. However, their insufficient electrocatalytic activity has considerably limited further development. Herein, oxygen-vacancy-rich BaFe0.6Ce0.2Sc0.2O3-δ (BFCS) perovskite is rationally designed by a facile Sc-substitution strategy for BaFe0.6Ce0.4O3-δ (BFC) as efficient and stable air electrode for PCCs. The BFCS electrode with an optimized Fe 3d-eg orbital occupancy and more oxygen vacancies exhibits a polarization resistance of ≈ 0.175 Ω cm2 at 600 °C, ≈ 1/3 of the BFC electrode (≈0.64 Ω cm2). Simultaneously, BFCS shows favorable proton uptake with a low proton defect formation enthalpy (- 81 kJ mol-1). By combining soft X-ray absorption spectroscopy and electrical conductivity relaxation studies, it is revealed that the enhancement of Fe4+-O2- interactions in BFCS promotes the activation and mobility of lattice oxygen, triggering the activity of BFCS in both oxygen reduction and evolution reactions (ORR/OER). The single cell achieves encouraging output performance in both fuel cell (1.55 W cm-2) and electrolysis cell (-2.96 A cm-2 at 1.3 V) modes at 700 °C. These results highlight the importance of activating lattice oxygen in air electrodes of PCCs.
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The interactions between the catalyst and support are widely used in many important catalytic reactions but the construction of strong interaction with definite microenvironments to understand the structure-activity relationship is still challenging. Here, strongly-interacted composites are prepared via selective exsolution of active NiSe2 from the host matrix of NiFe2O4 (S-NiSe2/NiFe2O4) taking advantage of the differences of migration energy, in which the NiSe2 possessed both high dispersion and small size. The characteristics of spatially resolved scanning transmission X-ray microscopy (STXM) coupled with analytical Mössbauer spectra for the surface and bulk electronic structures unveiled that this strongly interacted composite triggered more charge transfers from the NiSe2 to the host of NiFe2O4 while stabilizing the inherent atomic coordination of NiFe2O4. The obtained S-NiSe2/NiFe2O4 exhibits overpotentials of 290 mV at 10 mA cm-2 for oxygen evolution reaction (OER). This strategy is general and can be extended to other supported catalysts, providing a powerful tool for modulating the catalytic performance of strongly-interacted composites.
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Direct selective transformation of greenhouse methane (CH4) to liquid oxygenates (methanol) can substitute energy-intensive two-step (reforming/Fischer-Tropsch) synthesis while creating environmental benefits. The development of inexpensive, selective, and robust catalysts that enable room temperature conversion will decide the future of this technology. Single-atom catalysts (SACs) with isolated active centers embedded in support have displayed significant promises in catalysis to drive challenging reactions. Herein, high-density Ni single atoms are developed and stabilized on carbon nitride (NiCN) via thermal condensation of preorganized Ni-coordinated melem units. The physicochemical characterization of NiCN with various analytical techniques including HAADF-STEM and X-ray absorption fine structure (XAFS) validate the successful formation of Ni single atoms coordinated to the heptazine-constituted CN network. The presence of uniform catalytic sites improved visible absorption and carrier separation in densely populated NiCN SAC resulting in 100% selective photoconversion of (CH4) to methanol using H2O2 as an oxidant. The superior catalytic activity can be attributed to the generation of high oxidation (NiIIIâO) sites and selective CâH bond cleavage to generate â¢CH3 radicals on Ni centers, which can combine with â¢OH radicals to generate CH3OH.
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A Gram-stain-negative, aerobic, non-spore-forming, nonmotile, rod-shaped, and yellow-pigmented bacterium, designated strain JXAS1T, was isolated from a freshwater sample collected from Poyang Lake in China. Phylogenetic analysis based on 16S rRNA gene sequence revealed that the isolate belonged to the genus Flavobacterium, being closest to Flavobacterium pectinovorum DSM 6368T (98.61â%). The genome size of strain JXAS1T was 4.66 Mb with DNA G+C content 35.7 mol%. The average nucleotide identity and in silico DNA-DNA hybridization values between strain JXAS1T and its closest relatives were below the threshold values of 95 and 70â%, respectively. The strain contained menaquinone 6 (MK-6) as the predominant menaquinone and the major polar lipids were phosphatidylethanolamine, one unidentified glycolipid, and one unidentified polar lipid. The major fatty acids (>5â%) were iso-C15â:â0, summed feature 3 (C16â:â1 ω7c and/or C16â:â1 ω6c), C15â:â0, iso-C17â:â0 3OH, iso-C15â:â0 3OH, and summed feature 9 (iso-C17â:â1 ω9c and/or 10-methyl C16â:â0). Based on phylogenetic, genotypic, and phenotypic evidence, the isolated strain represents a new species in the genus Flavobacterium, and the name Flavobacterium poyangense is proposed. The type strain is JXAS1T (=GDMCC 1.1378T=KCTC 62719T).
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Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano , Ácidos Grasos , Flavobacterium , Lagos , Hibridación de Ácido Nucleico , Filogenia , ARN Ribosómico 16S , Análisis de Secuencia de ADN , Vitamina K 2 , Flavobacterium/genética , Flavobacterium/clasificación , Flavobacterium/aislamiento & purificación , Lagos/microbiología , China , ARN Ribosómico 16S/genética , Vitamina K 2/análogos & derivados , Vitamina K 2/análisis , ADN Bacteriano/genética , Fosfatidiletanolaminas , Glucolípidos/análisis , Fosfolípidos/análisisRESUMEN
Single atom catalysts (SACs) possess unique catalytic properties due to low-coordination and unsaturated active sites. However, the demonstrated performance of SACs is limited by low SAC loading, poor metal-support interactions, and nonstable performance. Herein, we report a macromolecule-assisted SAC synthesis approach that enabled us to demonstrate high-density Co single atoms (10.6 wt % Co SAC) in a pyridinic N-rich graphenic network. The highly porous carbon network (surface area of â¼186 m2 g-1) with increased conjugation and vicinal Co site decoration in Co SACs significantly enhanced the electrocatalytic oxygen evolution reaction (OER) in 1 M KOH (η10 at 351 mV; mass activity of 2209 mA mgCo-1 at 1.65 V) with more than 300 h stability. Operando X-ray absorption near-edge structure demonstrates the formation of electron-deficient Co-O coordination intermediates, accelerating OER kinetics. Density functional theory (DFT) calculations reveal the facile electron transfer from cobalt to oxygen species-accelerated OER.
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BACKGROUND & AIMS: Alterations of multiple metabolites characterize distinct features of metabolic reprograming in hepatocellular carcinoma (HCC). However, the role of most metabolites, including propionyl-CoA (Pro-CoA), in metabolic reprogramming and hepatocarcinogenesis remains elusive. In this study, we aimed to dissect how Pro-CoA metabolism affects these processes. METHODS: TCGA data and HCC samples were used to analyze ALDH6A1-mediated Pro-CoA metabolism and its correlation with HCC. Multiple metabolites were assayed by targeted mass spectrometry. The role of ALDH6A1-generated Pro-CoA in HCC was evaluated in HCC cell lines as well as xenograft nude mouse models and primary liver cancer mouse models. Non-targeted metabolomic and targeted energy metabolomic analyses, as well as multiple biochemical assays, were performed. RESULTS: Decreases in Pro-CoA and its derivative propionyl-L-carnitine due to ALDH6A1 downregulation were tightly associated with HCC. Functionally, ALDH6A1-mediated Pro-CoA metabolism suppressed HCC proliferation in vitro and impaired hepatocarcinogenesis in mice. The aldehyde dehydrogenase activity was indispensable for this function of ALDH6A1, while Pro-CoA carboxylases antagonized ALDH6A1 function by eliminating Pro-CoA. Mechanistically, ALDH6A1 caused a signature enrichment of central carbon metabolism in cancer and impaired energy metabolism: ALDH6A1-generated Pro-CoA suppressed citrate synthase activity, which subsequently reduced tricarboxylic acid cycle flux, impaired mitochondrial respiration and membrane potential, and decreased ATP production. Moreover, Pro-CoA metabolism generated 2-methylcitric acid, which mimicked the inhibitory effect of Pro-CoA on citrate synthase and dampened mitochondrial respiration and HCC proliferation. CONCLUSIONS: The decline of ALDH6A1-mediated Pro-CoA metabolism contributes to metabolic remodeling and facilitates hepatocarcinogenesis. Pro-CoA, propionyl-L-carnitine and 2-methylcitric acid may serve as novel metabolic biomarkers for the diagnosis and treatment of HCC. Pro-CoA metabolism may provide potential targets for development of novel strategies against HCC. IMPACT AND IMPLICATIONS: Our study presents new insights on the role of propionyl-CoA metabolism in metabolic reprogramming and hepatocarcinogenesis. This work has uncovered potential diagnostic and predictive biomarkers, which could be used by physicians to improve clinical practice and may also serve as targets for the development of therapeutic strategies against HCC.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Ratones , Animales , Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/patología , Citrato (si)-Sintasa , Carnitina/metabolismo , Carnitina/farmacologíaRESUMEN
BACKGROUND: Polydatin has shown considerable pharmacological activities in ischemia-reperfusion injuries of various organs. However, its effects and mechanisms in spinal cord ischemia-reperfusion injury have not been fully established. In this study, the mechanisms of polydatin against spinal cord ischemia-reperfusion injury were investigated via network pharmacology, molecular docking and molecular dynamics simulation. METHODS: Spinal cord ischemia-reperfusion injury-related targets were obtained from the GeneCards database, while polydatin-related action targets were obtained from the CTD and SwissTarget databases. A protein-protein interaction network of potential targets was constructed using the String platform. After selecting the potential key targets, GO functional enrichment and KEGG pathway enrichment analyses were performed via the Metascape database, and a network map of "drug-target-pathway-disease" constructed. The relationships between polydatin and various key targets were assessed via molecular docking. Molecular dynamics simulation was conducted for optimal core protein-compound complexes obtained by molecular docking. RESULTS: Topological analysis of the PPI network revealed 14 core targets. GO functional enrichment analysis revealed that 435 biological processes, 12 cell components and 29 molecular functions were enriched while KEGG pathway enrichment analysis revealed 91 enriched signaling pathways. Molecular docking showed that polydatin had the highest binding affinity for MAPK3, suggesting that MAPK3 is a key target of polydatin against spinal cord ischemia-reperfusion injury. Molecular dynamics simulations revealed good binding abilities between polydatin and MAPK3. CONCLUSIONS: Polydatin exerts its effects on spinal cord ischemia-reperfusion injury through multiple targets and pathways. MAPK3 may be a key target of polydatin in spinal cord ischemia-reperfusion injury.
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Simulación de Dinámica Molecular , Daño por Reperfusión , Médula Espinal , Humanos , Simulación del Acoplamiento Molecular , Farmacología en Red , Daño por Reperfusión/tratamiento farmacológicoRESUMEN
Polydatin is an active polyphenol displaying multifaceted benefits. Recently, growing studies have noticed its potential therapeutic effects on bone and joint disorders (BJDs). Therefore, this article reviews recent in vivo and in vitro progress on the protective role of polydatin against BJDs. An insight into the underlying mechanisms is also presented. It was found that polydatin could promote osteogenesis in vitro, and symptom improvements have been disclosed with animal models of osteoporosis, osteosarcoma, osteoarthritis and rheumatic arthritis. These beneficial effects obtained in laboratory could be mainly attributed to the bone metabolism-regulating, anti-inflammatory, antioxidative, apoptosis-regulating and autophagy-regulating functions of polydatin. However, studies on human subjects with BJDs that can lead to early identification of the clinical efficacy and adverse effects of polydatin have not been reported yet. Accordingly, this review serves as a starting point for pursuing clinical trials. Additionally, future emphasis should also be devoted to the low bioavailability and prompt metabolism nature of polydatin. In summary, well-designed clinical trials of polydatin in patients with BJD are in demand, and its pharmacokinetic nature must be taken into account.
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OBJECTIVE: This study investigated the molecular mechanism of whether hUC-MSCs-EVs repressed PTEN expression and activated the PI3K/AKT pathway through miR-29b-3p, thus inhibiting LPS-induced neuronal injury. METHODS: hUC-MSCs were cultured and then identified. Cell morphology was observed. Alizarin red, oil red O, and alcian blue staining were used for inducing osteogenesis, adipogenesis, and chondrogenesis. EVs were extracted from hUC-MSCs and identified by transmission electron microscope observation and Western blot. SCI neuron model was established by 24h lipopolysaccharide (LPS) induction. After the cells were cultured with EVs without any treatment, uptake of EVs by SCI neurons, miR-29b-3p expression, cell viability, apoptosis, caspase-3, cleaved caspase-3, caspase 9, Bcl-2, PTEN, PI3K, AKT, and p-Akt protein levels, caspase 3 and caspase 9 activities, and inflammatory factors IL-6 and IL-1ß levels were detected by immunofluorescence labeling, RT-qPCR, MTT, flow cytometry, Western blot, caspase 3 and caspase 9 activity detection kits, and ELISA. The binding sites between PTEN and miR-29b-3p were predicted by the database and verified by dual-luciferase assay. RESULTS: LPS-induced SCI cell model was successfully established, and hUC-MSCs-EVs inhibited LPS-induced apoptosis of injured spinal cord neurons. EVs transferred miR-29b-3p into LPS-induced injured neurons. miR-29b-3p silencing reversed EV effects on reducing LPS-induced neuronal apoptosis. miR-29b-3p reduced LPS-induced neuronal apoptosis by targeting PTEN. After EVs-miR-inhi and si-PTEN treatment, inhibition of the PI3K/AKT pathway reversed hUC-MSCs-EVs effects on reducing LPS-induced neuronal apoptosis. CONCLUSION: hUC-MSCs-EVs activated the PI3K/AKT pathway by carrying miR-29b-3p into SCI neurons and silencing PTEN, thus reducing neuronal apoptosis.
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Vesículas Extracelulares , Células Madre Mesenquimatosas , MicroARNs , Traumatismos de la Médula Espinal , Azul Alcián/metabolismo , Azul Alcián/farmacología , Apoptosis , Caspasa 3/metabolismo , Caspasa 9/metabolismo , Caspasa 9/farmacología , Vesículas Extracelulares/metabolismo , Humanos , Interleucina-6/metabolismo , Lipopolisacáridos/farmacología , MicroARNs/genética , MicroARNs/metabolismo , Neuronas/metabolismo , Fosfohidrolasa PTEN , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Traumatismos de la Médula Espinal/genética , Traumatismos de la Médula Espinal/metabolismo , Traumatismos de la Médula Espinal/terapia , Cordón Umbilical/metabolismoRESUMEN
Lithium-ion diffusion ability in solid electrolytes is crucial for the performance and safety of lithium-ion batteries. However, the lithium-ion diffusion coefficient of Li6.75La3Zr1.5Ta0.5O12 (LLZTO) measured experimentally is much lower than that simulated theoretically because LLZTO exists widely in the polycrystalline form rather than in the single-crystal form. Herein, we focus on the construction of grain boundaries in polycrystalline materials to address this key issue. An amorphous structure is created by randomly throwing atoms into a virtual box, where the chemical bonds are broken and rearranged through continuous heating and annealing operations, resulting in a stable framework structure. The lithium-ion diffusion coefficients of polycrystalline LLZTO and single-crystal LLZTO calculated via Ab initio molecular dynamics (AIMD) are consistent with the experimental data in trend. Furthermore, the analysis of the grain boundary composed of the secondary phase in polycrystalline LLZTO reveals that the continuous -O-M-O- metal oxide grid with low formation energy per atom restricts the lithium-ion migration. The lithium-ion migration barriers calculated utilizing density functional theory (DFT) also demonstrate the obstacle of the grain boundary from another perspective.
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BACKGROUND: This retrospective observational study was conducted to compare midterm outcomes of three bone graft struts for interbody fusion using a posterior approach in adults with lower lumbar spinal tuberculosis. METHODS: A total of 126 lower lumbar spinal tuberculosis patients were treated by one-stage posterior debridement, interbody fusion, and instrumentation. Forty-one patients (group A) were treated with autogenous bone graft for interbody fusion, 45 patients (group B) were treated with allogeneic bone grafting, and the remaining 40 (group C) patients were treated with titanium mesh cage. In addition, clinical and radiographic data were gathered and analyzed. RESULTS: At the final follow-up, all patients were completely cured. The operation period and intraoperative blood loss for groups B and C were significantly less than in group A (P = 0.000). Post-operation, neurological performance and quality of life were remarkably improved at the final follow-up. The preoperative lordosis angles of three groups were significantly improved, as evidenced by the values immediately after the operation or those at the final follow-up. The correction loss of the group C was lower than those of groups A and B (P = 0.000). All the patients obtained bone graft fusion, the fusion period of group B was longer than that of the other two groups (P = 0.000). No significant differences among the three groups in adjacent segment degeneration rates were found at the last visit (P = 0.922). CONCLUSIONS: This midterm follow-up study established that one-stage posterior debridement, interbody fusion, and instrumentation, combined with medical therapy, can effectively treat lower lumbar spinal tuberculosis. In addition, the intervertebral titanium mesh cage bone graft can provide better outcomes with regard to maintaining lordosis and preventing collapse.
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Lordosis , Fusión Vertebral , Tuberculosis de la Columna Vertebral , Adulto , Trasplante Óseo , Desbridamiento , Estudios de Seguimiento , Humanos , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/cirugía , Calidad de Vida , Estudios Retrospectivos , Titanio , Resultado del Tratamiento , Tuberculosis de la Columna Vertebral/diagnóstico por imagen , Tuberculosis de la Columna Vertebral/cirugíaRESUMEN
BACKGROUND: This retrospective study aimed to determine the feasibility and efficacy of endoscopy-assisted anterior cervical debridement combined with posterior fixation and fusion in patients with upper cervical spine tuberculosis. METHODS: Between June 2008 and January 2016, 17 patients (10 men and 7 women) with upper cervical spine tuberculosis underwent endoscopy-assisted anterior cervical debridement combined with posterior fixation and fusion. Anti-tuberculosis treatment was administered for 2-4 weeks preoperatively and 12-18 months postoperatively. The clinical and radiographic data of the patients were analyzed. RESULTS: The operation was successfully completed in all patients. Neck pain and stiffness were relieved after the surgery in all patients. The mean operation time was 210.0 ± 21.2 min, and the mean intraoperative blood loss was 364.7 ± 49.6 mL. The mean follow-up duration was 68.1 ± 6.7 months. The erythrocyte sedimentation rate returned to normal by 3 months postoperatively. Visual analog scale scores for neck pain were significantly lower postoperatively than preoperatively. All patients had significant postoperative neurological improvement. Patient-reported outcomes, as measured using the Kirkaldy-Willis criteria, were as follows: excellent, 12 patients; good, 4 patients; fair, 1 patient; and poor, 0 patients. Bone fusion was achieved at 10.9 ± 1.9 months after the surgery; no cases of instrument loosening or fracture occurred. CONCLUSION: Endoscopy-assisted anterior cervical debridement combined with posterior fixation and fusion is a feasible and effective surgical method for the treatment of upper cervical spine tuberculosis. It can be used to restore upper cervical spine stability and facilitate spinal healing.
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Fusión Vertebral , Tuberculosis de la Columna Vertebral , Vértebras Cervicales/diagnóstico por imagen , Vértebras Cervicales/cirugía , Desbridamiento , Endoscopía , Estudios de Factibilidad , Femenino , Humanos , Masculino , Estudios Retrospectivos , Fusión Vertebral/efectos adversos , Vértebras Torácicas , Resultado del Tratamiento , Tuberculosis de la Columna Vertebral/diagnóstico por imagen , Tuberculosis de la Columna Vertebral/cirugíaRESUMEN
The electronic structure of composites plays a critical role in photocatalytic conversion, whereas it is challenging to modulate the orbital for an efficient catalyst. Herein, we regulated the t2g orbital occupancy state of Ti to realize efficient CO2 conversion by adjusting the amount of photo-deposited Cu in the Cu/TiO2 composite. For the optimal sample, considerable electrons transfer from the Cu d orbital to the Ti t2g orbital, as proven by X-ray absorption spectroscopy. The Raman spectra results also corroborate the electron enrichment on the Ti t2g orbital. Further theoretical calculations suggested that the orbital energy of the Ti 3d orbital in TiO2 is declined, contributing to accepting Cu 3d electrons. As a result, the Cu/TiO2 composite exhibited an extremely high selectivity of 95.9 % for CO, and the productivity was 15.27â µmol g-1 h-1 , which is almost 6â times that of the original TiO2 . Our work provides a strategy for designing efficient photocatalysis as a function of orbital regulation.
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Pediatric solid tumors are heterogeneous and comprise various histological subtypes. TP53, a tumor suppressor, orchestrates the transcriptional activation of anti-cancer genes. The gene coding for this protein is highly polymorphic, and its mutations are associated with cancer development. The Arg72Pro polymorphism in TP53 has been associated with susceptibility to various types of cancer. Here, in this hospital-based study, we evaluated the association of this polymorphism with susceptibility toward malignant abdominal solid tumors in children in the Hunan province of China. We enrolled 162 patients with neuroblastoma, 60 patients with Wilms' tumor, and 28 patients with hepatoblastoma as well as 270 controls. Genotypes were determined using a TaqMan assay, and the strength of the association was assessed using an odds ratio, within a 95% confidence interval identified using logistic regression models. Our results showed that the Arg72Pro polymorphism did not exhibit significant association with susceptibility toward pediatric malignant abdominal solid tumors. Stratification analysis revealed that this polymorphism exerts weak sex- and age-specific effects on Wilms' tumor and hepatoblastoma susceptibility, respectively. Overall, our results indicate that the Arg72Pro polymorphism may have a marginal effect on susceptibility toward pediatric malignant abdominal solid tumors in Hunan, and this finding warrants further confirmation.
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Neoplasias Abdominales/genética , Neuroblastoma/genética , Proteína p53 Supresora de Tumor/genética , Adolescente , Arginina/genética , Estudios de Casos y Controles , Femenino , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Masculino , Polimorfismo de Nucleótido Simple , Factores de RiesgoRESUMEN
The development of a biodegradable cellulose-based separator with excellent performance has been of great research significance and application potential for the green development of supercapacitors. Herein, the regenerated porous cellulose/Polyvinyl alcohol films (CP-10, CP-15, CP-20, CP-25) with different mass ratio were successfully fabricated by a simple blending and phase inversion process. Their electrochemical properties as separators in assembled supercapacitor were evaluated. Fourier transform infrared spectroscopy and x-ray diffraction analysis indicate that intermolecular and intramolecular hydrogen bonding existed between cellulose and polyvinyl alcohol of the CP films. Compared with other CP films, the CP-20 film shows higher mechanical strength (28.02 MPa), better wettability (79.06°), higher porosity (59.69%) and electrolyte uptake (281.26 wt%). These properties of CP-20 are expected to show better electrochemical performance as separator. Indeed, the electrochemical tests, including electrochemical impedance spectroscopy, cyclic voltammetry, galvanostatic charge discharge, demonstrate that the SC-20 capacitor (with CP-20 as separator) shows the lowest equivalent series resistance of 0.57 Ω, the highest areal capacitance of 1.98 F cm-2 at 10 mV s-1, specific capacitance of 134.41 F g-1 and charge-discharge efficiency of 98.62% at 1 A g-1 among the four capacitors with CP films as separators. Comparing the assembled SC-40 and SC-30 with two commercial separators (TF4040 and MPF30AC) and SC-PVA with Polyvinyl alcohol (PVA) separator, the CV and GCD curves of SC-20 maintain the quasi rectangular and symmetrical triangular profiles respectively at different scan rates in potential window of 0-1 V. SC-20 exhibits the highest value of 28.24 Wh kg-1 at 0.5 A g-1 with a power density of 0.26 kW kg-1, and 13.41 Wh kg-1 at 10 A g-1 with a power density of 6.04 kW kg-1. SC-20 also shows the lowest voltage drop and the highest areal and specific capacitance. Moreover, SC-20 maintains the highest value of 86.81% after 4000 cycles compared to 21.18% of SC-40, 75.07% of SC-30, and 6.66% of SC-PVA, showing a superior rate capability of a supercapacitor. These results indicate that CP films can be served as promising separators for supercapacitors.
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OBJECTIVES: The therapeutic effect of acupuncture treatments (AT) on functional gastrointestinal disorders (FGIDs) is contentious. A meta-analysis was conducted to assess the efficacy and safety of acupuncture for FGIDs. METHODS: The Cochrane Library, EMBASE, PUBMED, Web of Science, Wanfang Database, China National Knowledge Infrastructure, and VIP Database were searched through December 31, 2019 with no language restrictions. Risk ratio (RR) with 95% confidence interval (CI) was calculated to determine the improvement in symptom severity after treatment. RESULTS: A total of 61 randomized controlled trials (RCTs) on FGIDs were included. The pooled results illustrated the following: compared to pharmacotherapy (RR 1.13, 95% CI 1.09-1.17), placebo acupuncture (RR 1.69, 95% CI 1.37-2.08), no specific treatment (RR 1.86, 95% CI 1.31-2.62), and AT as an adjuvant intervention to other active treatments (RR 1.25, 95% CI 1.21-1.30), AT had more favorable improvements in symptom severity; sub-group analysis results classified according to functional dyspepsia, irritable bowel syndrome, and functional constipation also supported this finding; and the incidence of adverse events was lower in AT than in other treatments (RR 0.75, 95% CI 0.56-0.99). CONCLUSIONS: This meta-analysis found that AT was significantly associated with relief of FGIDs symptoms; however, the evidence level was moderate or low. Further data from rigorously designed and well powered RCTs are needed to verify the effectiveness and safety of AT as a FGIDs treatment. PROSPERO PROTOCOL NUMBER: CRD42020169508.
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Terapia por Acupuntura , Enfermedades Gastrointestinales , Estreñimiento/terapia , Dispepsia/terapia , Enfermedades Gastrointestinales/terapia , Humanos , Síndrome del Colon Irritable/terapia , Ensayos Clínicos Controlados Aleatorios como AsuntoRESUMEN
BACKGROUND: To explore the therapeutic effect of early surgical intervention for active thoracic spinal tuberculosis (TB) patients with paraparesis and paraplegia. METHODS: Data on 118 active thoracic spinal TB patients with paraparesis and paraplegia who had undergone surgery at an early stage (within three weeks of paraparesis and paraplegia) from January 2008 to December 2014 were retrospectively analyzed. The operation duration, blood loss, perioperative complication rate, VAS score, ASIA grade and NASCIS score of neurological status rating, Erythrocyte Sedimentation Rate (ESR), C-reactive protein (CRP), kyphotic Cobb's angle, and duration of bone graft fusion were analyzed to evaluate the therapeutic effects of surgery. RESULTS: The mean operating time was 194.2 minutes, and the mean blood loss was 871.2 ml. The perioperative complication rate was 5.9 %. The mean preoperative VAS score was 5.3, which significantly decreased to 3.2 after the operation and continued decreasing to 1.1 at follow up (P<0.05). All cases achieved an increase of at least one ASIA grade after operation. The rate of full neurological recovery for paraplegia (ASIA grade A and B) was 18.0 % and was significantly lower than the rate (100 %) for paraparesis (ASIA grade C and D) (P<0.05). On the NASCIS scale, the difference in the neurological improvement rate between paraplegia (22.2 % ± 14.1 % in sensation and 52.2 % ± 25.8 % in movement) and paraparesis (26.7 % ± 7.5 % in sensation and 59.4 % ± 7.3 % in movement) was remarkable (P<0.05). Mean preoperative ESR and CRP were 73.1 mm /h and 82.4 mg/L, respectively, which showed a significant increase after operation (P>0.05), then gradually decreased to 11.5 ± 1.8 mm/h and 2.6 ± 0.82 mg/L, respectively, at final follow up (P<0.05). The mean preoperative kyphotic Cobb's angle was 21.9º, which significantly decreased to 6.5º after operation (P<0.05) while kyphotic correction was not lost during follow up (P>0.05). The mean duration of bone graft fusion was 8.6 ± 1.3 months. CONCLUSIONS: Early surgical intervention may be beneficial for active thoracic spinal TB patients with paraparesis and paraplegia, with surgical intervention being more beneficial for recovery from paraparesis than paraplegia.