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1.
BMC Cancer ; 23(1): 295, 2023 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-37004004

RESUMO

BACKGROUND: The prognostic value of cytokeratin 19 fragment (CYFRA 21 - 1) and Ki67 in advanced non-small cell lung cancer (NSCLC) patients with wild-type epidermal growth factor receptor (EGFR) remains to be explored. METHODS: In this study, 983 primary NSCLC patients from January 2016 to December 2019 were retrospectively reviewed. Finally, 117 advanced NSCLC patients with wild-type EGFR and 37 patients with EGFR mutation were included and prognostic value of CYFRA 21 - 1 and Ki67 were also identified. RESULTS: The patients age, smoking history and the Eastern Corporative Oncology Group (ECOG) performance scores were significantly different between CYFRA21-1 positive and negative groups (p < 0.05), while no significant differences were found in Ki67 high and low groups. The results of over survival (OS) demonstrated that patients with CYFRA21-1 positive had markedly shorter survival time than CYFRA21-1 negative (p < 0.001, For whole cohorts; p = 0.002, For wild-type EGFR). Besides, patients with wild-type EGFR also had shorter survival times than Ki67 high group. Moreover, In CYFRA 21 - 1 positive group, patients with Ki67 high had obviously shorter survival time compared to patients with Ki67 low (median: 24vs23.5 months; p = 0.048). However, Ki67 could not be used as an adverse risk factor for patients with EGFR mutation. Multivariate cox analysis showed that age (HR, 1.031; 95%CI, 1.003 ~ 1.006; p = 0.028), Histopathology (HR, 1.760; 95%CI,1.152 ~ 2.690; p = 0.009), CYFRA 21 - 1 (HR, 2.304; 95%CI,1.224 ~ 4.335; p = 0.01) and Ki67 (HR, 2.130; 95%CI,1.242 ~ 3.652; p = 0.006) served as independent prognostic risk factor for advanced NSCLC patients. CONCLUSIONS: Our finding indicated that CYFRA 21 - 1 was an independent prognostic factor for advanced NSCLC patients and Ki67 status could be a risk stratification marker for CYFRA 21 - 1 positive NSCLC patients with wild-type EGFR.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/genética , Queratina-19/genética , Prognóstico , Neoplasias Pulmonares/genética , Estudos Retrospectivos , Receptores ErbB/genética , Mutação , Biomarcadores Tumorais/genética
2.
Redox Biol ; 56: 102437, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36037588

RESUMO

Maternal stress has been associated with poor birth outcomes, including preterm birth, infant mortality, and low birth weight. Bone development disorders in the embryo as a result of maternal stress are believed to be mediated through oxidative stress damage. Various species of free radicals, such as alkoxyl radicals, can be formed through endogenous redox response or exogenous stimuli in the womb and transmitted to embryos. Yet, whether these free radicals lead to abnormal fetal bone development is unclear. Here, we demonstrate prenatal bone growth retardation and ferroptosis-related signals of chondrocytes were induced by classic alkoxyl radical generators. We also show that alkoxyl radicals lead to significant accumulation of oxidized phospholipids in chondrocytes, through the iron-mediated Fenton reaction in embryos. We further demonstrate a role for the lipid peroxidation end product, 4-HNE, which forms adducts with the pivotal chondrogenesis transcription factor SOX9, leading to its degradation, therefore dampening chondrogenesis. Our data define a critical role for phospholipid peroxidation in alkoxyl radicals-evoked abnormal chondrogenesis, and pinpoint it being a precise target for treating oxidative stress-related bone development disorders.


Assuntos
Fosfolipídeos , Nascimento Prematuro , Álcoois , Desenvolvimento Ósseo , Condrogênese , Feminino , Radicais Livres/metabolismo , Humanos , Recém-Nascido , Ferro , Peroxidação de Lipídeos , Fosfolipídeos/metabolismo , Fatores de Transcrição/metabolismo
3.
Langmuir ; 38(13): 4111-4120, 2022 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-35312331

RESUMO

Self-driven droplet transport along an open gradient surface is increasingly becoming popular for various microfluidics applications. In this work, a gradient copper oxide layer is formed on a copper sheet (as a bipolar electrode, BPE) in a KOH solution by bipolar electrochemistry. The deposits at different positions present a rich variety of colors, compositions, and microstructures along the longitudinal axis of the BPE. More than half the length of the anodic pole is covered by a Cu(OH)2/CuO composite layer of several micrometers thick, which is composed of dense micropillars with a decreasing spacing gradient to the anodic direction. The micropillar arrays are superhydrophilic, and after modified with 1-dodecanethiol, the tops of the dense micropillars constitute a hydrophobic and microscopically discontinuous surface with a wettability gradient. On such a gradient surface water droplets can move spontaneously to more hydrophilic direction at a velocity of about 16 mm s-1. The superhydrophobicity of the modified micropillar arrays is discussed through a comparison with the wax tubules on a lotus leaf. Theoretical analysis of the driving force reveals that the concave surface effect of water at the spacings between the micropillars is the critical factor for driving the rolling motion of the droplets along the gradient micropillar arrays.

4.
ChemSusChem ; 14(18): 3926-3934, 2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34288529

RESUMO

Platinum usually offers the most effective active center for hydrogen evolution reaction (HER), because of the optimal trade-off between the adsorption and desorption of hydrogeN atoms (H*) on Pt atoms. Herein, we report an unusual result regarding the active center of a HER catalyst, which was synthesized by electrodepositing traces of Pt nanoparticles (NPs) into a porous nitrogen-rich dodecahedron matrix derived from zeolitic imidazolate framework ZIF-8. With an ultra-low Pt loading of 2.76 µg cm-2 , the N-Pt-bonded catalyst can produce a current density of 117 mA cm-2 for the HER in 1.0 m H2 SO4 at an overpotential of 50 mV, whereas the commercial Pt/C (300 µg cm-2 Pt) can only reach 50 mA cm-2 under the same conditions. Cyclic voltammetry demonstrates that both the H* adsorption and the Pt oxidation are not allowed to occur on this catalyst, due to a full surface coverage of the trace Pt NPs by imidazole. The results from the specially designed experiments indicate that the imidazole N atoms may act as proton anchor-sites for the HER due to their electron donor nature. Density functional theory calculations also support a catalytic HER mechanism centered at the Pt-supported N active center, which needs a Gibbs free energy of H* absorption (ΔGH* ) significantly smaller than the absolute value of ΔGH* on the Pt(111) surface. We hope that the results of this study will encourage the research on novel N-centered catalysts for the HER.

5.
ChemSusChem ; 14(15): 3131-3138, 2021 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-34076965

RESUMO

Low-cost and efficient bifunctional catalysts are urgently needed for overall water splitting used in large-scale energy storage. In this study, we develop a nickel and iron (di)sulfide (Ni-Fe-S) composite catalyst that is in situ synthesized and fixed within the intergranular nanopores inside high pure polycrystalline graphite. Two precursor solutions (reactants) may permeate the graphite intergranular pores to a depth of more than 3.5 mm. The nanoscale pores serve as an array of nanoreactors for the synthesis of the Ni-Fe-S nanoparticles under conditions much milder than usual. The prepared catalyst efficiently catalyzes both the hydrogen and oxygen evolution reactions (HER and OER) in 1.0 M KOH. It delivers a current density of 400 mA cm-2 at a full cell voltage of around 2.3 V without considerable activity decay over 24 h electrolysis. The active species of the catalyst are different for the HER and OER and discussed accordingly. The synthesis strategy based on the nanopores in a monolithic conductive substrate proves to be a simple, efficient, and promising way to prepare electrocatalysts that are cheap, abundant, and industrially attractive.

6.
Dalton Trans ; 50(2): 715-721, 2021 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-33346261

RESUMO

Ferrate(vi), [FeO4]2-, is a very powerful oxidant that can oxidize a wide variety of inorganic and organic compounds. However, the mechanisms of many of these oxidation reactions have not been studied in detail. In this work, we have investigated the kinetics and mechanism of the oxidation of 4-alkylbenzenesulfonates by ferrate in aqueous solutions at pH 7.45-9.63 by UV/Vis spectrophotometry. The reactions are first order with respect to both [ferrate] and [4-alkylbenzenesulfonate]. The second-order rate constants for the oxidation of 4-isopropylbenzenesulfonate by ferrate at 25 °C and I = 0.3 M are found to be (5.86 ± 0.08) × 10-1 M-1 s-1 and (4.11 ± 1.50) × 10-3 M-1 s-1 for [Fe(O)3(OH)]- and [FeO4]2-, respectively, indicating that [Fe(O)3(OH)]- is two orders of magnitude more reactive than [FeO4]2- and is the predominant oxidant in neutral and slightly alkaline solutions. This is further supported by the effect of the ionic strength on the rate constant. No solvent kinetic isotope effect (KIE) was found but a moderate primary KIE = 1.6 ± 0.1 was observed in the oxidation of 4-ethylbenzenesulfonate and 4-ethylbenzenesulfonate-d9. Alkyl radicals were trapped by CBrCl3 in the oxidation of alkylarenes by ferrate. Combined with DFT calculations, a hydrogen atom transfer (HAT) mechanism was proposed for the reactions between [Fe(O)3(OH)]- and 4-alkylbenzenesulfonates.

7.
Ann Transl Med ; 8(20): 1315, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33209895

RESUMO

BACKGROUND: Non-dominant population, which means patients with advanced non-squamous lung cancer or non-small cell lung cancer (NSCLC) without driver-mutations, who are excluded from clinical studies because of specific baseline conditions refractory to multiple treatments, have poor outcomes. We assessed the activity of pemetrexed first-line treatment for a non-dominant population, explore the safety and efficacy of pemetrexed therapy. METHODS: We did this two-phased, single-arm trial at two sites at the Fifth Affiliated Hospital of Sun Yat-sen University and Guangxi medical university cancer hospital. Pemetrexed 500 mg/m2, static drops on day 1; 21 days for a cycle, each treatment for at least two cycles and up to six cycles. Efficacy was assessed every two cycles. RESULTS: We counted the July 21, 2018 to 2020 on May 31, first diagnosed with IIIb-IV period (American Joint Committee on Cancer eighth edition) no drive genes, non-squamous cell carcinomas, 30 patients with non-small cell lung cancer, the follow-up to July 31, 2020, median follow-up time was 12 months. Most were elderly patients with poor general conditions (96.7% of patients had ECOG scores of 2-3) (median age 66 years). Median duration of maintenance treatment was 6 months. Median progression-free survival was 6.5 months. Median overall survival was 12 months. Patients with performance status =0-2 had a significantly higher median overall survival time (16 months) compared with patients with performance status =3 who had a median overall survival time of 7 months (P=0.001). Most treatment-related adverse events were grade 1 or grade 2. CONCLUSIONS: This study is the first to investigate the survival benefit and toxicity tolerance of pemetrexed treatment in non-dominant population in the real world, providing a new therapeutic possibility for those who failed to be enrolled in clinical studies.

8.
Langmuir ; 36(19): 5126-5133, 2020 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-32336103

RESUMO

Iron incorporation is essential for the record activity of NiFe-(oxy)hydroxides to oxygen evolution reaction (OER), but the details of how Fe affects catalysis remain under active investigation. In this work, we present a double thin-layer strategy for finding unique and solid evidence for the role of Fe in the OER mechanism. A thin-layer catalyst of a few nanometers of thickness was deposited on a Ni substrate and a thin-layer electrolyte of 0.1 mm thickness was created using a thin-layer spectroelectrochemical cell. The OER activity, the catalyst composition, and the electrolyte species were investigated together as a function of the Fe deposition time. The results show that trace Fe incorporation favors the formation of ß-NiOOH in the thin-layer catalyst and effectively suppresses the dissolution of NiOOH into the electrolyte. The results of double-potential step chronoabsorptometry and cyclic voltabsorptometry demonstrate the potential-dependent formation of a Ni3+ intermediate in the electrolyte and, more importantly, the dissolution suppression effect due to Fe incorporation. These findings link the role of Fe in OER catalysis to the increased insolubility of Ni3+ active sites and highlight the importance of paying close attention to the active-site stability of an electrocatalyst impaired by the electrolyte at a reaction potential.

9.
Cancer Manag Res ; 12: 881-889, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32104070

RESUMO

PURPOSE: Our study aimed to construct a visible model to evaluate the risk of infectious complications after gastrectomy. METHODS: The clinical data of 856 patients who underwent gastrectomy were used to retrieve medical records. Univariate and multivariate analyses were performed to correlate early postoperative NLR and operative variables with postoperative complications, and the construction of the nomogram was based on logistic regression. The concordance index and receiver operating characteristic curves were used to evaluate the model performance. RESULTS: The postoperative infectious and noninfectious complication rates after gastrectomy were 18.5% (158/856 cases) and 12.3% (105/856 cases) respectively. Postoperative NLR (within 24 h) independently predicted the development of postoperative infectious complication. Multivariate analysis revealed that age, diabetes, body mass index (BMI), intraoperative blood transfusion and postoperative NLR were independent risk factors. The nomogram model showed a good performance in terms of predicting infectious complications after gastrectomy (concordance index=0.718). CONCLUSION: Age, diabetes, BMI, intraoperative blood transfusion and postoperative NLR were independent risk factors of postoperative infectious complications after gastrectomy, and a novel nomogram based on these results can be used to predict postoperative infection and has the advantages of simple application and easy access.

10.
Calcif Tissue Int ; 106(4): 401-414, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31912171

RESUMO

The aim of this study was to distinguish the characteristics of intervertebral disc degeneration (IVDD) originating from mechanics imbalance, biology disruption, and their communion, and to develop a composite IVDD model by ovariectomy combined with lumbar facetectomy for mimicking elderly IVDD with osteoporosis and lumbar spinal instability. Mice were randomly divided into four groups and subjected to sham surgery (CON), ovariectomy (OVX), facetectomy (mechanical instability, INS) or their combination (COM), respectively. Radiographical (n = 4) and histological changes (n = 8) of L4/5 spinal segments were analyzed. Tartrate-resistant acid phosphatase (TRAP) staining was conducted to detect osteoclasts, and expression of osterix (OSX), type I collagen (Col I), type II collagen (Col II) and vascular endothelial growth factor (VEGF) were evaluated by immunochemistry. OVX affected the body's metabolism but INS did not, as the body weight increased and uterus weight decreased in OVX and COM mice compared to CON and INS mice. OVX, INS, and COM caused IVDD in various degrees at 12 weeks after surgery. However, the major pathogeneses of OVX- and INS-induced IVDD were different, which focused on endplate (EP) remodeling and annulus fibrosus (AF) collapse, respectively. OVX induced osteopenia of vertebra. In contrast, INS promoted the stress-adaptive increase of subchondral bone trabeculae. The COM produced a reproducible severe IVDD model with characteristics of sparse vertebral trabeculae, cartilaginous EP ossification, subchondral bone sclerosis, fibrous matrix disorder, angiogenesis, disc stiffness, as well as space fusion. Additionally, all groups had elevated bone and cartilage turnover compared with CON group, as the quantity of trap + osteoclasts and the osteogenic OSX expression increased in these groups. Likewise, the VEGF expression levels were similar, accompanied by the altered matrix expression of disc, including the changed distribution and contents of Col II and Col I. The findings suggested that the composite mouse model to some extent could effectively mimic the interactions of biology and mechanics engaged in the onset and natural course of IVDD, which would be more compatible with the IVDD of elderly with vertebral osteoporosis and spinal instability and benefit to further clarify the complicated mechanobiological environment of elderly IVDD progression.


Assuntos
Doenças Ósseas Metabólicas/metabolismo , Degeneração do Disco Intervertebral/cirurgia , Vértebras Lombares/cirurgia , Osteoporose/cirurgia , Animais , Conservadores da Densidade Óssea/farmacologia , Doenças Ósseas Metabólicas/complicações , Colágeno Tipo II/efeitos dos fármacos , Colágeno Tipo II/metabolismo , Modelos Animais de Doenças , Vértebras Lombares/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Osteoporose/complicações
11.
Org Lett ; 21(22): 8888-8892, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31592667

RESUMO

Asymmetric conjugate addition of aryl halides or aryl triflates to electron-deficient olefins was realized by sequential Miyaura borylation and Hayashi-Miyaura conjugate addition in one pot. A nickel-catalyzed borylation of aryl halides or triflates and a rhodium-chiral diene complex catalyzed enantioselective conjugate addition was executed as a pair of relay reactions as a more efficient and greener protocol.

12.
Arthritis Res Ther ; 20(1): 207, 2018 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-30201052

RESUMO

BACKGROUND: Studies on the relationship between osteoporosis and intervertebral disc degeneration (IVDD) are inconsistent. Therefore, we assessed whether IVDD is affected by vertebral osteoporosis in ovariectomized mice and investigated the underlying pathogenesis of IVDD related to osteoporosis. METHODS: Thirty healthy female C57BL/6 J mice aged 8 weeks were randomly divided into two groups: a control group (sham operation, n = 15) and an ovariectomy group (OVX; bilateral ovariectomy, n = 15). At 12 weeks after surgery, the bone quantity and microstructure in the lumbar vertebra and endplate as well as the volume of the L4/5 disc space were evaluated by microcomputed tomography (micro-CT). The occurrence and characteristic alterations of IVDD were identified via histopathological staining. The osteoclasts were detected using tartrate-resistant acid phosphatase (TRAP) staining. Type II collagen (Col II), osterix (OSX), osteopontin (OPN), and vascular endothelial growth factor (VEGF) expression in the intervertebral disc were detected by immunohistochemical analysis. RESULTS: OVX significantly increased the body weight and decreased the uterus weight. Micro-CT analysis showed that osteoporosis of the vertebra and osteochondral remodeling of the endplate were accompanied by an increase in the endplate porosity and a decrease in the disc volume in the OVX group. Likewise, histological evaluation revealed that IVDD occurred at 12 weeks after ovariectomy, with features of endochondral ossification of the endplate, loose and broken annulus fibrosus, and degeneration of nucleus pulposus. TRAP staining showed that numerous active osteoclasts appeared in the subchondral bone and cartilaginous endplate of OVX mice, whereas osteoclasts were rarely detected in control mice. Immunohistochemical analysis demonstrated that the expression of osterix was significantly increased, notably in the endplate of OVX mice. In addition, Col II was decreased in the ossification endplate and the degenerative annulus fibrosus, where OPN and VEGF expressions were elevated in OVX mice. CONCLUSIONS: OVX induced vertebral osteoporosis and osteochondral remodeling of the cartilaginous endplate contributing to the angiogenesis and an increase in porosity of the bone-cartilage surface, and also affected the matrix metabolism which consequently had detrimental effects on the intervertebral disc. Our study suggests that preserving the structural integrity and the function of the adjacent structures, including the vertebrae and endplates, may protect the disc against degeneration.


Assuntos
Remodelação Óssea/fisiologia , Condrócitos/patologia , Degeneração do Disco Intervertebral/patologia , Vértebras Lombares/patologia , Ovariectomia/efeitos adversos , Animais , Condrócitos/metabolismo , Feminino , Degeneração do Disco Intervertebral/metabolismo , Vértebras Lombares/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Ovariectomia/tendências
13.
Biochem Biophys Res Commun ; 504(1): 61-67, 2018 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-30190124

RESUMO

Intracerebral haemorrhage (ICH) is a common and devastating cerebrovascular disease with high morbidity and mortality, and its pathophysiological mechanisms were complex and still unclear. Increasing researches reported that microRNAs (miRNAs) played an important role in ICH-induced brain injury and microglial activation. In this study, we investigated the biological function of miR-590-5p and explored its molecular mechanism in ICH mice. The results of qRT-PCR showed that miR-590-5p expression level was down-regulated in perihematomal brain samples of ICH mice compared with that of sham group. In LPS-induced microglia cells, miR-590-5p level was also down-regulated at 24 h post-LPS compared with that of control group. Moreover, miR-590-5p overexpression remarkably increased the cerebral water content and neurological severity scores compared with that of scramble group in ICH mice. The production of inflammatory cytokine including IL-6, interleukin (IL)-1ß, and tumor necrosis factor (TNF)-α in ICH mice was notably inhibited by miR-590-5p overexpression. Furthermore, the results of dual-luciferase reporter assay indicated that Pellino-1 (Peli1) was a direct target of miR-590-5p. MiR-590-5p overexpression remarkably inhibited the Peli1 gene expression both mRNA and protein levels. In addition, Peli1 overexpression partly abrogated the inhibitory effect of miR-590-5p mimic. Taken together, these datas suggested that miR-590-5p attenuated brain injury in ICH mice through inhibiting Peli1 gene expression, indicating that miR-590-5p may be a promising molecular target for ICH treatment.


Assuntos
Lesões Encefálicas/genética , Hemorragia Cerebral/complicações , Regulação da Expressão Gênica , MicroRNAs/metabolismo , Proteínas Nucleares/genética , Ubiquitina-Proteína Ligases/genética , Animais , Lesões Encefálicas/etiologia , Lesões Encefálicas/metabolismo , Células Cultivadas , Hemorragia Cerebral/genética , Hemorragia Cerebral/metabolismo , Regulação para Baixo , Masculino , Camundongos Endogâmicos C57BL , Microglia/metabolismo , Proteínas Nucleares/metabolismo , Ubiquitina-Proteína Ligases/metabolismo
14.
Chem Commun (Camb) ; 54(72): 10116-10119, 2018 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-30124708

RESUMO

The roles of soluble Fe and Ni species in the alkaline oxygen evolution reaction (OER) at a Ni anode are reported. The Fe impurities in the electrolyte turn out to be insufficient to directly improve the OER activity. The Ni(OH)2/NiOOH film undergoes chemical dissolution to give a stable Ni(ii) species that plays a hindering role in the OER.

15.
Opt Express ; 26(3): 2972-2982, 2018 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-29401830

RESUMO

Taking advantage of technology of spatio-temporal reconstruction and dispersive Fourier transform (DFT), we experimentally observed the buildup dynamics of dissipative soliton in an ultrafast fiber laser in the net-normal dispersion regime. The soliton buildup dynamics were analyzed in both the spectral and temporal domains. We firstly revealed that the appearing of the spectral sharp peaks with oscillation structures during the mode-locking transition is caused by the formation of structural dissipative soliton. The experimental results were explained by the numerical simulations. These findings would give some new insights into the dissipative soliton buildup dynamics in ultrafast fiber lasers.

16.
Yi Chuan ; 40(1): 22-32, 2018 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-29367190

RESUMO

GATA binding protein 6 (GATA6) is a member of the GATA family of zinc-finger transcriptional regulators, whose names come from the conservative base sequence (G/A)GATA(A/T). The GATA families play key roles in cell fate determination, proliferation, migration, and organogenesis of endoderm- and mesoderm-derived organs in vertebrates. As a lineage-specific factor, a chromatin remodeling factor, a pluripotent factor and a pioneer factor, GATA6 is involved in various stages of liver development, including endoderm liver-lineage determination, liver specification, hepatic bud outgrowth and hepatoblast differentiation. In this review, we summarize recent progress in the roles and regulatory mechanisms of GATA6 in liver development.


Assuntos
Fator de Transcrição GATA6/fisiologia , Fígado/embriologia , Animais , Endoderma/embriologia , Fator de Transcrição GATA6/química , Humanos
17.
ACS Appl Mater Interfaces ; 9(39): 33855-33862, 2017 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-28906102

RESUMO

Retaining soluble polysulfides in the sulfur cathodes and allowing for deep redox are essential to develop high-performance lithium-sulfur batteries. The versatile textures and physicochemical characteristics of abundant biomass offer a great opportunity to prepare biochar materials that can enhance the performance of Li-S batteries in sustainable mode. Here, we exploit micro-/mesoporous coconut shell carbon (CSC) with high specific surface areas as a sulfur host for Li-S batteries. The sulfur-infiltrated CSC materials show superior discharge-charge capacity, cycling stability, and high rate capability. High discharge capacities of 1599 and 1500 mA h g-1 were achieved at current rates of 0.5 and 2.0 C, respectively. A high reversible capacity of 517 mA h g-1 was retained at 2.0 C even after 400 cycles. The results demonstrate a high retention and a deep lithiation of the CSC-confined sulfur. The success of this strategy provides insights into seeking high-performance biochar materials for Li-S batteries from abundant bioresources.

18.
Arch Osteoporos ; 12(1): 14, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28127706

RESUMO

Osteoporosis is characterized by an increasing osseous fragility and fracture resulting from the low mass and deteriorated microarchitecture in the bone tissue. The hormone replacement therapy and alendronate were frequently used to treat osteoporosis as the primary therapeutic strategy, but their adverse effects have severely limited their extensive clinical application, therefore, it is urgent to develop alternative or complementary therapeutic agents for anti-osteoporosis. Interestingly, with more people focusing on the complementary and alternative medicine, traditional Chinese herbs and formulas are being gradually recognized as safe and effective agents in the treatment of osteoporosis. In particular, a notable trend is that increasing studies are making efforts to clarify the anti-osteoporotic effects and mechanism of the tonifying kidney-yin herbs and formulas, a category of agents identified as effective therapy. Therefore, the purpose of this study is to comprehensively review the tonifying kidney-yin herbs and formulas that have been reported in the treatment of osteoporosis as well as how the agents play their roles in detail. This current study not only will advance our understanding of the actions of tonifying kidney-yin herbs and formulas, but also provide new evidence for the clinic use of the tonifying kidney-yin herbs and formulas in the treatment of osteoporosis.


Assuntos
Osso e Ossos , Medicamentos de Ervas Chinesas/farmacologia , Osteoporose/tratamento farmacológico , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/patologia , Humanos , Osteoporose/diagnóstico
19.
Org Biomol Chem ; 14(42): 9970-9973, 2016 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-27722669

RESUMO

A general and effective method for the synthesis of amides through decarboxylative amidation of α-keto acids with amines has been developed. The reaction proceeded smoothly to afford the corresponding amide products in good yield under air and shows excellent functional group tolerance. In addition, the protocol can be further applied in the synthesis of heterocyclic compounds like benzimidazoles.

20.
ACS Appl Mater Interfaces ; 8(34): 22261-9, 2016 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-27502841

RESUMO

A highly conductive sulfur cathode is crucial for improving the kinetic performance of a Li-S battery. The encapsulation of sulfur in porous nanocarbons is expected to benefit the Li(+) migration, yet the e(-) conduction is still to be improved due to a low graphitization degree of a conventional carbon substrate, especially that pyrolyzed from carbohydrates or polymers. Aiming at facilitating the e(-) conduction in the cathode, here we propose to use ketjen black, a highly graphitized nanocarbon building block to form a conductive network for electrons in a biomass-derived, hierarchically porous carbon sponge by a easily scaled-up approach at a low cost. The specifically designed carbon host ensures a high loading and good retention of active sulfur, while also provides a faster electron transmission to benefit the lithiation/delithiation kinetics of sulfur. The sulfur cathode prepared from the carbon network shows excellent cycling and rate performance in a Li-S battery, rendering its practicality for emerging energy storage opportunities such as grids or automobiles.

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