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1.
Org Lett ; 25(34): 6401-6406, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37603790

RESUMO

A convenient and efficient trans-stereoselective and ß-regioselective hydroboration of propargyl alcohols was achieved simply with LiOtBu as the base and (Bpin)2 as the boron reagent in dimethyl sulfoxide at room temperature. Both terminal and internal propargyl alcohols with diverse structures and functional groups underwent the transformation smoothly to produce ß-Bpin-substituted (E)-allylic alcohols, of which the synthetic potentials were demonstrated by the downstream conversions of boronate, alkenyl, and hydroxyl groups.

2.
Adv Mater ; 34(28): e2202256, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35546336

RESUMO

The lithium-sulfur (Li-S) battery is considered as an appealing candidate for next-generation electrochemical energy storage systems because of high energy and low cost. Nonetheless, its development is plagued by the severe polysulfide shuttling and sluggish reaction kinetics. Although single-atom catalysts (SACs) have emerged as a promising remedy to expedite sulfur redox chemistry, the mediocre single-atom loading, inferior atomic utilization, and elusive catalytic pathway handicap their practical application. To tackle these concerns, in this work, unsaturated Fe single atoms with high loading capacity (≈6.32 wt%) are crafted on a 3D hierarchical C3 N4 architecture (3DFeSA-CN) by means of biotemplated synthesis. By electrokinetic analysis and theoretical calculations, it is uncovered that the 3DFeSA-CN harnesses robust electrocatalytic activity to boost dual-directional sulfur redox. As a result, S@3DFeSA-CN can maintain a durable cyclic performance with a negligible capacity decay rate of 0.031% per cycle over 2000 cycles at 1.0 C. More encouragingly, an assembled Li-S battery with a sulfur loading of 5.75 mg cm-2 can harvest a high areal capacity of 6.18 mAh cm-2 . This work offers a promising solution to optimize the carbonaceous support and coordination environment of SACs, thereby ultimately elevating dual-directional sulfur redox in pragmatic Li-S batteries.

3.
Ann Palliat Med ; 11(2): 655-662, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35249343

RESUMO

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) has become a major public health problem concern in recent decades. The specific mechanism of NAFLD is still not clear. Previous studies had shown the correlation between NAFLD and thyroid dysfunction. The correlation between thyroid hormones within the euthyroid range and NAFLD has not yet been clarified. This study sought to investigate the association between NAFLD and thyroid hormones in euthyroid patients. METHODS: A retrospective cross-sectional study was conducted at Beijing Tiantan Hospital from January 1, 2019, to October 1, 2021. Eighty-one NAFLD patients with normal thyroid function and 34 healthy individuals were enrolled. Participants' demographic information, biochemical parameters, and thyroid hormone levels were collected. The severity of NAFLD was assessed by abdominal computed tomography (CT). The association between NAFLD and thyroid hormones was analyzed. RESULTS: Patients in the NAFLD group were older and more likely to be female than those in the healthy control group (P<0.05). Compared to the healthy control group, the serum levels of fasting plasma glucose (FPG), alanine transaminase (ALT), plasma aspartate transaminase (AST), triglyceride, gamma-glutamyl transferase (γ-GT), and uric acid (UA) were higher, but the levels of high-density lipoprotein cholesterol (HDL-C), and free thyroxine (FT4) were lower in the NAFLD group (P<0.05). NAFLD is more severe in females than males (P<0.05). ALT, AST, low-density lipoprotein cholesterol (LDL-C), γ-GT, tetraiodothyronine, and free triiodothyronine (FT3) levels increased significantly as the severity of NAFLD increased (P<0.05). The results of the Spearman correlation analysis indicated that the severity of NAFLD was positively correlated with ALT (r=0.376, P=0.001), AST (r=0.275, P=0.015), and LDL (r=0.313, P=0.007). The multiple logistic regression analysis showed that age [odds ratio (OR) =1.071; 95% confidence interval (CI): 1.010-1.136, P=0.021], ALT (OR =1.091; 95% CI: 1.034-1.150, P=0.001), HDL-C (OR =0.085; 95% CI: 0.010-0.690, P=0.021), and FT4 (OR =0.738; 95% CI: 0.545-1.001, P=0.046) were independently related to the risk of NAFLD in patients with normal thyroid function. CONCLUSIONS: FT4 within the normal range was lower in the NAFLD group compared to the healthy control group. The serum level of FT4 is an independent risk factor of NAFLD in euthyroid people.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Estudos Transversais , Feminino , Humanos , Masculino , Estudos Retrospectivos , Fatores de Risco , Hormônios Tireóideos , Tireotropina , Tiroxina
4.
Org Lett ; 23(23): 9094-9099, 2021 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-34780200

RESUMO

Iron-catalyzed direct SN2' dehydroxyboration of allylic alcohols has been developed to access (E)-stereoselective allylboronates. Allylic alcohols with diverse structures and functional groups, especially derived from natural products, underwent smooth transformation. The six-membered ring transition state formed by allylic alcohols and iron-boron intermediate was indicated to be the key component involved in transfer of the boron group, activation of the C-OH bond, and control of the stereoselectivity.

5.
Med Sci Monit ; 26: e923188, 2020 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-32522972

RESUMO

BACKGROUND The aim of the study was to assess the effect of circRNA CDYL on myocardial angiogenesis after acute myocardial infarction (AMI). MATERIAL AND METHODS We compared changes in circRNA CDYL and myocardial angiogenesis in myocardial infarction tissue and normal heart tissue by establishing a myocardial infarction mouse model to clarify the relationship between circRNA CDYL and changes in myocardial infarction and myocardial angiogenesis. Secondly, we used the RegRNA website to predict downstream miRNA, and we performed gain-of-function and loss-of-function experiments. RESULTS CircCDYL was downregulated in myocardial tissues and hypoxia myocardial cells, and overexpression and downregulation of circCDYL improved and aggravated, respectively, heart function after AMI. CircCDYL overexpression and downregulation can promote and inhibit, respectively, proliferation of cardiomyocytes in vitro. Finally, we found that circCDYL can sponge miR-4793-5p and regulate its expression, and then miR-4793-5p regulates APP expression. CONCLUSIONS CircCDYL can promote the proliferation of cardiomyocytes through the miR-4793-5p/APP pathway.


Assuntos
Proteínas Correpressoras/genética , Hidroliases/genética , Infarto do Miocárdio/genética , Infarto do Miocárdio/metabolismo , Animais , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células/fisiologia , Proteínas Correpressoras/metabolismo , Feminino , Hidroliases/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/genética , Infarto do Miocárdio/patologia , Miocárdio/metabolismo , Miocárdio/patologia , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , RNA Circular/genética , RNA Circular/metabolismo , Regeneração , Transdução de Sinais
6.
Bioengineered ; 11(1): 53-60, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-31884873

RESUMO

Long non-coding RNAs (lncRNAs) recently have been implicated in many biological processes and diseases. Atherosclerosis is a major risk factor for cardiovascular disease. However, the functional role of lncRNAs in atherosclerosis is largely unknown. Here we identified LOC285194 as a key regulator of cell proliferation and apoptosis during atherosclerosis. The expression of LOC285194 was dramatically down-regulated in a aortic atherosclerotic plaques of well-defined model of apolipoprotein-E knockout (ApoE-/-) mice. Moreover, we found that targeting LOC285194 results in neointimal hyperplasia in vivo in carotid artery injury model. We also showed that targeting LOC285194 promotes cell proliferation and inhibits apoptosis in vascular smooth muscle cells (VSMCs) in vitro, and vice versa. In addition, targeting LOC285194 promotes cell invasion and migration in vitro. Our studies identify LOC285194 as a novel regulator of cell proliferation and apoptosis and suggest that this lncRNA could serve as a therapeutic target to treat atherosclerosis and related cardiovascular disorders.


Assuntos
Apoptose , Aterosclerose/fisiopatologia , Músculo Liso Vascular/citologia , RNA Longo não Codificante/metabolismo , Animais , Apolipoproteínas E/genética , Apolipoproteínas E/metabolismo , Aterosclerose/genética , Aterosclerose/metabolismo , Movimento Celular , Proliferação de Células , Feminino , Humanos , Masculino , Camundongos , Camundongos Knockout , Músculo Liso Vascular/metabolismo , RNA Longo não Codificante/genética
7.
J Biosci Bioeng ; 127(3): 345-352, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30241903

RESUMO

The inhibitory effects of ammonium and sulfide on the methane production using acetate or propionate as a carbon source were investigated under different pH and temperature conditions. The methane production rate, duration of the lag phase, and inhibition threshold limit during methane production were estimated using the Gompertz equation and inhibitor mathematical model. The methane production rates at 53°C were 2.3-2.7 times higher than those at 35°C in the case of non-inhibitors. Increasing the NH4+ and/or S2- concentration decreased the methane production rate and increased the duration of the lag phase. For methane fermentation that was not acclimated to high NH4+ concentration, the critical NH4+ concentration beyond which methane fermentation would stop was 4000-5650 mg/L, depending on the pH, temperature, and carbon source. When NH4+ and S2- were coexistent, the critical NH4+ concentration decreased to approximately 3800 mg/L when propionate was used and to approximately 4450 mg/L when acetate was used. However, no synergistic effect of NH4+ and S2- on the methane production rate was found at an NH4+ concentration of < 5000 mg/L and S2- concentration of 50 mg/L.


Assuntos
Ácido Acético/metabolismo , Compostos de Amônio/farmacologia , Fermentação/efeitos dos fármacos , Metano/biossíntese , Propionatos/metabolismo , Sulfetos/farmacologia , Concentração de Íons de Hidrogênio , Temperatura
8.
Angew Chem Int Ed Engl ; 56(11): 2937-2941, 2017 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-28185385

RESUMO

A new family of sulfur-rich phosphorus sulfide molecules (P4 S10+n ) and their electrochemical reaction mechanism with metallic Li has been explored. These P4 S10+n molecules are synthesized by the reaction between P4 S10 and S. For Li batteries, the P4 S40 molecule in the series of P4 S10+n molecules provides the highest capacity, which has a first discharge capacity of 1223 mAh g-1 at 100 mA g-1 and stabilizes at approximately 720 mAh g-1 at 500 mA g-1 after 100 cycles. This new class of sulfur-rich P4 S10+n molecules and its electrochemical behavior for room-temperature Li+ storage could provide novel insights for phosphorus sulfide molecules and high-energy batteries.

9.
Nanoscale ; 7(8): 3440-4, 2015 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-25644942

RESUMO

Recently, a unique process based on the Kirkendall effect was employed to generate hollow nanostructures with a wide variety of materials. However, a similar hollow structure of silicon based on the fabrication mechanism of the Kirkendall effect is still not proposed. Here, we provide an extensible synthesis method for the high yield fabrication of a uniform vesica-like hollow Si material from SiO2 based on the Kirkendall effect in a molten salt reduction process. Significantly, without further modification, the as-prepared hollow vesica-like Si exhibits a high electrochemical storage capacity and long cycling properties (∼712 mA h g(-1) at 0.36 A g(-1) over 200 cycles).

10.
J Surg Res ; 191(2): 413-22, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25060322

RESUMO

BACKGROUND: There is no consensus as to the impact of lymph node micrometastases (LNMM) on survival of patients with gastric cancer. The aim of this analysis was to investigate the prognostic significance of LNMM in patients with histologic node-negative gastric cancer. METHODS: We searched relevant studies from PubMed, Embase, and the Cochrane Library (1966-2013.5), used software STATA 12.0 to pool the outcomes of each study. Mantel-Haenszel and Inverse Variance methods were used in a fixed effect model and a random effect model, respectively. The hazard ratios (HR) and odds risk (OR) at their 95% confidence intervals (CIs) were used as measures to investigate the prognostic importance of LNMM, by searching for a correlation between the clinical pathologic features and LNMM. RESULTS: Our analysis of 18 eligible studies revealed that patients with LNMM had an increased likelihood of having a worse 5-y survival rate (HR 2.81; 95% CI: 1.96-4.02). Subgroup analyses showed a more significant result for patients in pT1-2N0 (HR 3.52; 95% CI 1.88-6.62). The analyses also revealed that (OR 1.32; 95% CI 1.17-1.48), lymphatic invasion (OR 2.21; 95% CI 1.42-3.44) and venous invasion (OR 1.41; 95% CI 1.08-1.85) were associated with the occurrence of LNMM. CONCLUSIONS: There is a positive correlation between LNMM and an unfavorable surgical outcome in gastric cancer. Undifferentiated histologic findings, lymphatic invasion, and venous invasion are high risk factors for the occurrence of LNMM.


Assuntos
Micrometástase de Neoplasia , Neoplasias Gástricas/patologia , Humanos , Metástase Linfática , Estadiamento de Neoplasias , Estudos Observacionais como Assunto , Prognóstico , Viés de Publicação , Neoplasias Gástricas/mortalidade , Taxa de Sobrevida
11.
Chempluschem ; 79(1): 143-150, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31986750

RESUMO

A new thread for improving the cycling stability of Fe2 O3 nanorice is proposed through combining the electrochemical porousness (EP) effect and solid-electrolyte interphase (SEI) thermolysis approach. Starting from solid Fe2 O3 nanorice, this process could be applied to prepare porous Fe2 O3 nanorice with a good coating of a porous SEI thermolysis layer composed of carbon and Li2 O. The interconnecting pores and full coating of the SEI thermolysis layer provides not only mechanical resistance of the Fe2 O3 nanorice against pulverization, but also high electrical and ionic conductivity over the electrode throughout long cell cycles. This method results in the enhancement of cycling ability and capacity, which is demonstrated by comparison with the starting Fe2 O3 nanorice. After the EP and SEI thermolysis approach, the Fe2 O3 nanorice exhibits an energy capacity retention about of 680 mAh g-1 at a current density of 1000 mA g-1 over 250 cycles, which is more than 82 % of the initial reversible capacity. Moreover, it also has an excellent rate capability and high coulombic efficiency. This strategy provides a simple and convenient route toward stable charge/discharge cycling for not only Fe2 O3 , but also for other electrode materials that are subject to large volume changes and low charge voltages. At the same time, it also contributes to a fundamental understanding of improved cycling stability and reversible capacity for electrode materials.

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