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1.
Surg Endosc ; 37(3): 1700-1709, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36207648

RESUMO

BACKGROUND: The need for intraoperative endoscopic nasobiliary drainage during laparoscopic cholecystectomy and laparoscopic common bile duct exploration with primary closure is controversial in the treatment of cholecystolithiasis combined with choledocholithiasis. The aim of this study was to evaluate the safety and efficacy of laparoscopic cholecystectomy + laparoscopic common bile duct exploration + intraoperative endoscopic nasobiliary drainage + primary closure (LC + LCBDE + IO-ENBD + PC). The safety of different intubation methods in IO-ENBD was also evaluated. METHOD: From January 2018 to January 2022, 168 consecutive patients with cholecystolithiasis combined with choledocholithiasis underwent surgical treatment in our institution. Patients were divided into two groups: group A (n = 96) underwent LC + LCBDE + IO-ENBD + PC and group B (n = 72) underwent LC + LCBDE + PC. Patient characteristics, perioperative indicators, complications, stone residual, and recurrence rates were analyzed. Group A was divided into two subgroups. In group A1, the nasobiliary drainage tube was placed in an anterograde way, and in group A2, nasobiliary drainage tube was placed in an anterograde-retrograde way. Perioperative indicators and complications were analyzed between subgroups. RESULTS: No mortality in the two groups. The operation success rates in groups A and B were 97.9% (94/96) and 100% (72/72), respectively. In group A, two patients were converted to T-tube drainage. The stone clearance rates of group A and group B were 100% (96/96) and 98.6% (71/72), respectively. Common bile duct diameter was smaller in group A [10 vs. 12 mm, P < 0.001] in baseline data. In perioperative indicators, group A had a longer operation time [165 vs.135 min, P < 0.001], but group A had a shorter hospitalization time [10 vs.13 days, P = 0.002]. The overall complications were 7.3% (7/96) in group A and 12.5% (9/72) in group B. Postoperative bile leakage was less in group A [0% (0/96) vs. 5.6% (4/72), P = 0.032)]. There were no residual and recurrent stones in group A. And there were one residual stone and one recurrent stone in group B (all 1.4%). The median follow-up time was 12 months in group A and 6 months in group B. During the follow-up period, 2 (2.8%) patients in group B had a mild biliary stricture. At subgroup analysis, group A1 had shorter operation time [150 vs. 182.5 min, P < 0.001], shorter hospitalization time [9 vs. 10 days, P = 0.002], and fewer patients with postoperative elevated pancreatic enzymes [32.6% (15/46) vs. 68% (34/50), P = 0.001]. CONCLUSION: LC + LCBDE + IO-ENBD + PC is safer and more effective than LC + LCBDE + PC because it reduces hospitalization time and avoids postoperative bile leakage. In the IO-ENBD procedure, the antegrade placement of the nasobiliary drainage tube is more feasible and effective because it reduces the operation time and hospitalization time, and also reduces injury to the duodenal papilla.


Assuntos
Colecistectomia Laparoscópica , Colecistolitíase , Coledocolitíase , Laparoscopia , Humanos , Coledocolitíase/complicações , Coledocolitíase/cirurgia , Colecistolitíase/complicações , Colecistolitíase/cirurgia , Ducto Colédoco/cirurgia , Colecistectomia Laparoscópica/efeitos adversos , Colecistectomia Laparoscópica/métodos , Drenagem/métodos , Laparoscopia/métodos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Estudos Retrospectivos , Colangiopancreatografia Retrógrada Endoscópica/métodos
2.
J Geriatr Cardiol ; 19(10): 743-752, 2022 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-36338278

RESUMO

BACKGROUND: Several studies have proved the safety and feasibility of robot-assisted percutaneous coronary intervention (PCI) in reducing the occupational hazards of interventionists while achieving precision medicine. However, an independently developed robot-assisted system for PCI in China has not yet emerged. This study aimed to evaluate the safety and feasibility of a robot-assisted system for elective PCI in China. METHODS: This preclinical trial included 22 experimental pigs and preliminarily supported the safety and feasibility of the ETcath200 robot-assisted system for PCI. Then, eleven patients with coronary heart disease who met the inclusion criteria and had clinical indications for elective PCI were enrolled. PCI was performed using a robot-assisted system. The primary outcomes were clinical success (defined as visual estimated residual stenosis < 30% after PCI and no major adverse cardiovascular events during hospitalization and within 30 days after PCI) and technical success (defined as the ability to use the robot-assisted system to complete PCI successfully without conversion to the traditional manual PCI). RESULTS: Eleven patients were included in this clinical trial. A drug-eluting stent with a diameter of 3 mm (interquartile range: 2.75-3.5 mm) and a length of 26 mm (interquartile range: 22-28 mm) was deployed in all patients. The clinical success rate was 100%, with no PCI-related complications and no in-hospital or 30-day major adverse cardiovascular events, and the technical success rate was 100%. CONCLUSIONS: The results strongly suggest that the use of the independently developed robot-assisted system in China for elective PCI is feasible, safe, and effective.

3.
Opt Express ; 30(13): 22608-22623, 2022 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-36224954

RESUMO

High-flux measurement characteristics of compressed sensing (CS) imaging causes the imaging system prone to be disturbed by quantization. To realize high-quality CS imaging with limited detector bits, an improved imaging method combining sparse measurements and multiple dithers is proposed to reduce the dynamic range of the measured signals and increase that of effective detection. Simulations and experiments show that compared with traditional CS imaging, the proposed system decreases reconstruction errors caused by quantization distortions and may reduce the required number of detector bits to 1. The effects of detector noise and system parameters are discussed to validate the feasibility and performance of this method.

4.
Angew Chem Int Ed Engl ; 61(35): e202207108, 2022 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-35789523

RESUMO

Production of more than 20 million tons of epoxides per year from olefins suffers from low atom economy due to the use of oxidants and complex catalysts with unsatisfactory selectivity, leading to huge environmental and economic costs. We present a proof-of-concept application of electron-rich RuO2 nanocrystals to boost the highly selective epoxidation of cyclooctene via direct oxygen transfer from water as the sole oxygen source under mild conditions. The enhanced electron enrichment of RuO2 nanocrystals via the Schottky effect with nitrogen-doped carbons largely promotes the capture and activation of cyclooctene to give a high turnover frequency (260 h-1 ) of cyclooctene oxide, far surpassing the reported values (<20 h-1 ) of benchmarked catalysts at room temperature with oxidants. Our electron-rich RuO2 electrocatalysts enable efficient and durable hydrogen production (Faradaic efficiency >90 %) on the cathode without impacting on the selectivity to epoxide (>99 %) on the anode.

5.
Small ; 18(19): e2200885, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35396794

RESUMO

Solar-driven production of hydrogen peroxide (H2 O2 ), as an important industrial chemical oxidant with an extensive range of applications, from oxygen reduction is a sustainable alternative to mainstream anthraquinone oxidation and direct hydrogenation of dioxygen methods. The efficiency of solar to hydrogen peroxide over semiconductor-based photocatalysts is still largely limited by the narrow light absorption to visible light. Here, the authors proposed and demonstrate the proof-of-concept application of light-generated hot electrons in a graphene/semiconductor (exemplified with widely used TiO2 ) dyad to largely extend visible light spectra up to 800 nm for efficient H2 O2 production. The well-designed graphene/semiconductor heterojunction has a rectifying interface with a zero barrier for the hot electron injection, largely boosting excited hot electrons with an average lifetime of ≈0.5 ps into charge carriers with a long fluorescent lifetime (4.0 ns) for subsequent H2 O2 production. The optimized dyadic photocatalyst can provide an H2 O2 yield of 0.67 mm g-1  h-1 under visible light irradiation (λ ≥ 400 nm), which is 20 times of the state-of-the-art noble-metal-free titanium oxide-based photocatalyst, and even achieves an H2 O2 yield of 0.14 mm g-1  h-1 upon photoexcitation by near-infrared-region light (≈800 nm).

6.
J Am Chem Soc ; 144(12): 5418-5423, 2022 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-35230846

RESUMO

Merging existing catalysts together as a cascade catalyst may achieve "one-pot" synthesis of complex but functional molecules by simplifying multistep reactions, which is the blueprint of sustainable chemistry with low pollutant emission and consumption of energy and materials only when the smooth mass exchange between different catalysts is ensured. Effective strategies to facilitate the mass exchange between different active centers, which may dominate the final activity of various cascade catalysts, have not been reached until now, even though charged interfaces due to work function driven electron exchange have been widely observed. Here, we successfully constructed mass (reactants and intermediates) exchange paths between Pd/N-doped carbon and MoC/N-doped carbon induced by interfacial electron exchange to trigger the mild and cascade methylation of amines using CO2 and H2. Theoretical and experimental results have demonstrated that the mass exchange between electron-rich MoC and electron-deficient Pd could prominently improve the production of N,N-dimethyl tertiary amine, which results in a remarkably high turnover frequency value under mild conditions, outperforming the state-of-the-art catalysts in the literature by a factor of 5.9.


Assuntos
Dióxido de Carbono , Elétrons , Aminas/química , Carbono/química , Dióxido de Carbono/química , Catálise
7.
Front Immunol ; 12: 741268, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34745113

RESUMO

Objective: We aimed to evaluate the diagnostic value of soluble interleukin-2 receptor (sIL-2R), tumor necrosis factor-α (TNF-α), procalcitonin (PCT), and combined detection for sepsis infection in patients with closed abdominal injury complicated with severe multiple abdominal injuries. Patients and Methods: One hundred forty patients with closed abdominal injury complicated with severe multiple abdominal injuries who were diagnosed and treated from 2015 to 2020 were divided into a sepsis group (n = 70) and an infection group (n = 70). Results: The levels of sIL-2R, TNF-α, and PCT in the sepsis group were higher than those in the infection group (p < 0.05). The receiver operating characteristic (ROC) curve showed that the areas under the ROC curve (AUCs) of sIL-2R, TNF-α, PCT and sIL-2R+TNF-a+PCT were 0.827, 0.781, 0.821, and 0.846, respectively, which were higher than those of white blood cells (WBC, 0.712), C-reactive protein (CRP, 0.766), serum amyloid A (SAA, 0.666), and IL-6 (0.735). The AUC of the three combined tests was higher than that of TNF-α, and the difference was statistically significant (p < 0.05). There was no significant difference in the AUCs of sIL-2R and TNF-α, sIL-2R and PCT, TNF-α and PCT, the three combined tests and sIL-2R, and the three combined tests and PCT (p > 0.05). When the median was used as the cut point, the corrected sIL-2R, TNF-α, and PCT of the high-level group were not better than those of the low-level group (p > 0.05). When the four groups were classified by using quantile as the cut point, the OR risk values of high levels of TNF-α and PCT (Q4) and the low level of PCT (Q1) after correction were 7.991 and 21.76, respectively, with statistical significance (p < 0.05). Conclusions: The detection of sIL-2R, TNF-α, and PCT has good value in the diagnosis of sepsis infection in patients with closed abdominal injury complicated with severe multiple abdominal injuries. The high concentrations of PCT and TNF-α can be used as predictors of the risk of septic infection.


Assuntos
Traumatismos Abdominais/diagnóstico , Traumatismo Múltiplo/diagnóstico , Pró-Calcitonina/sangue , Receptores de Interleucina-2/sangue , Sepse/diagnóstico , Fator de Necrose Tumoral alfa/sangue , Traumatismos Abdominais/complicações , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Traumatismo Múltiplo/complicações , Valor Preditivo dos Testes , Prognóstico , Risco , Sepse/etiologia
8.
Zhongguo Zhong Yao Za Zhi ; 46(20): 5185-5193, 2021 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-34738418

RESUMO

Quercetin is a naturally occurring phytochemical with good bioactivity, which mainly exists in the form of glycoside in vegetables, fruits, tea, and wine and exhibits beneficial health effects. Quercetin is a dietary polyphenol that exerts the protective effects through diet or use as a food supplement. Compared with chemical agents, quercetin is widely available and safe. Quercetin has been extensively studied for its anti-diabetic, anti-hypertensive, anti-Alzheimer's disease, anti-arthritic, anti-influenza virus, anti-microbial infection, anti-aging, autophagy-regulating, and cardiovascular protective effects. Studies on its activities against different can-cer cell lines have also been reported recently. However, the poor water solubility, rapid in vivo metabolism, and short half-life of quercetin have led to its low bioavailability, thus limiting its application in the field of medicine. Quercetin nanoparticles and nanoparticle drug delivery system have been effectively utilized for enhancing its bioavailability. This paper reviewed the therapeutic potential of quercetin from both preclinical and clinical aspects and proposed solutions to improve its bioavailability, so as to provide a reference for the therapeutic application of natural compounds in the field of medicine.


Assuntos
Nanopartículas , Quercetina , Disponibilidade Biológica , Sistemas de Liberação de Medicamentos , Solubilidade
9.
Zhongguo Zhong Yao Za Zhi ; 46(18): 4654-4665, 2021 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-34581073

RESUMO

Compounds derived from natural products present satisfactory efficacy in disease prevention and treatment. The use of chemical substances in plants to promote healthhas increasingly attracted people's attention. Rutin, a typical flavonoid, is mainly found in various vegetables, fruits and Chinese herbal medicines. As a natural antioxidant, it features many pharmacological activities, such as anti-inflammation, anti-virus, anti-tumor, and prevention and treatment of cardiovascular and cerebrovascular diseases. However, the low bioavailability and poor water solubility limit its clinical application. In view of this, its structure is optimized and modified to afford rutin derivatives with good solubility, high bioavailability, stable metabolism and small toxic side effects. So far, a large number of rutin ethers, esters, and complexes have been synthesized and undergone activity testing. This paper reviews the structural modification of rutin in recent years, and the obtained derivatives have excellent properties and significant biological activity.


Assuntos
Anti-Inflamatórios , Rutina , Antioxidantes , Disponibilidade Biológica , Humanos , Solubilidade
10.
Angew Chem Int Ed Engl ; 60(49): 25766-25770, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34585481

RESUMO

Platinum (Pt) is the most effective bench-marked catalyst for producing renewable and clean hydrogen energy by electrochemical water splitting. There is demand for high HER catalytic activity to achieve efficient utilization and minimize the loading of Pt in catalysts. In this work, we significantly boost the HER mass activity of Pt nanoparticles in Ptx /Co to 8.3 times higher than that of commercial Pt/C by using Co/NC heterojunctions as a heterogeneous version of electron donors. The highly coupled interfaces between Co/NC and Pt metal enrich the electron density of Pt nanoparticles to facilitate the adsorption of H+ , the dissociation of Pt-H bonds and H2 release, giving the lowest HER overpotential of 6.9 mV vs. RHE at 10 mA cm-2 in acid among reported HER electrocatalysts. Given the easy scale-up synthesis due to the stabilization of ultrafine Pt nanoparticles by Co/NC solid ligands, Ptx /Co can even be a promising substitute for commercial Pt/C for practical applications.

11.
Angew Chem Int Ed Engl ; 60(38): 20711-20716, 2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34313361

RESUMO

NOx - reduction acts a pivotal part in sustaining globally balanced nitrogen cycle and restoring ecological environment, ammonia (NH3 ) is an excellent energy carrier and the most valuable product among all the products of NOx - reduction reaction, the selectivity of which is far from satisfaction due to the intrinsic complexity of multiple-electron NOx - -to-NH3 process. Here, we utilize the Schottky barrier-induced surface electric field, by the construction of high density of electron-deficient Ni nanoparticles inside nitrogen-rich carbons, to facilitate the enrichment and fixation of all NOx - anions on the electrode surface, including NO3 - and NO2 - , and thus ensure the final selectivity to NH3 . Both theoretical and experimental results demonstrate that NOx - anions were continuously captured by the electrode with largely enhanced surface electric field, providing excellent Faradaic efficiency of 99 % from both electrocatalytic NO3 - and NO2 - reduction. Remarkably, the NH3 yield rate could reach the maximum of 25.1 mg h-1 cm-2 in electrocatalytic NO2 - reduction reaction, outperforming the maximum in the literature by a factor of 6.3 in neutral solution. With the universality of our electrocatalyst, all sorts of available electrolytes containing NOx - pollutants, including seawater or wastewater, could be directly used for ammonia production in potential through sustainable electrochemical technology.

12.
Biosci Trends ; 15(3): 161-170, 2021 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-34078766

RESUMO

This study aimed to investigate the value of multidisciplinary team (MDT) management in minimally invasive treatment of complex intrahepatic bile duct stones (IHDs) by laparoscopy, choledochoscopy and percutaneous choledochoscopy. The characteristics, perioperative index, complication rate and minimally invasive rate of patients in MDT group (n = 75) and non-MDT group (n = 70) were compared. The members of MDT include doctors in ultrasound, imaging, hepatobiliary and pancreatic surgery, anaesthesia and intensive care medicine. The results showed that minimally invasive surgery reduced the incidence of postoperative residual stones, OR (95% CI) = 0.365 (0.141-0.940) (p = 0.037). MDT reduced the operation time, OR (95% CI) = 0.406 (0.207-0.796) (p = 0.009). Minimally invasive surgery significantly reduced intraoperative bleeding, OR (95% CI) = 0.267 (0.133-0.534) (p < 0.001). Minimally invasive surgery also reduced hospitalization time, OR (95% CI) = 0.295 (0.142-0.611) (p = 0.001). The stone clearance rates of MDT group and non-MDT group were 81.33% and 81.43% respectively. In the MDT group, the operative time was less than that in the non-MDT group (p = 0.010); the intraoperative bleeding volume was significantly less than that in the non-MDT group (p < 0.001); the hospitalization time was less than that in the non-MDT group (p = 0.001). Minimally invasive operation rate:48 cases (64.00%) in MDT group were significantly higher than 17 cases (24.29%) in non-MDT group (p < 0.001). In conclusion, minimally invasive procedures can be selected more through MDT. MDT can shorten the operation time, and minimally invasive surgery can reduce the incidence of residual stones, reduce intraoperative bleeding, and may shorten hospital stay. Therefore, MDT management model can provide personalized and minimally invasive surgical protocol for patients with complex IHD, which has high application value.


Assuntos
Colelitíase/cirurgia , Endoscopia do Sistema Digestório/métodos , Laparoscopia/métodos , Equipe de Assistência ao Paciente , Complicações Pós-Operatórias/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Ductos Biliares/diagnóstico por imagem , Ductos Biliares/patologia , Ductos Biliares/cirurgia , Perda Sanguínea Cirúrgica/estatística & dados numéricos , Colelitíase/diagnóstico , Endoscopia do Sistema Digestório/efeitos adversos , Feminino , Seguimentos , Humanos , Laparoscopia/efeitos adversos , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle , Recidiva , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
13.
Nat Commun ; 12(1): 3882, 2021 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-34162882

RESUMO

The activation of C-H bonds is a central challenge in organic chemistry and usually a key step for the retro-synthesis of functional natural products due to the high chemical stability of C-H bonds. Electrochemical methods are a powerful alternative for C-H activation, but this approach usually requires high overpotential and homogeneous mediators. Here, we design electron-deficient W2C nanocrystal-based electrodes to boost the heterogeneous activation of C-H bonds under mild conditions via an additive-free, purely heterogeneous electrocatalytic strategy. The electron density of W2C nanocrystals is tuned by constructing Schottky heterojunctions with nitrogen-doped carbon support to facilitate the preadsorption and activation of benzylic C-H bonds of ethylbenzene on the W2C surface, enabling a high turnover frequency (18.8 h-1) at a comparably low work potential (2 V versus SCE). The pronounced electron deficiency of the W2C nanocatalysts substantially facilitates the direct deprotonation process to ensure electrode durability without self-oxidation. The efficient oxidation process also boosts the balancing hydrogen production from as-formed protons on the cathode by a factor of 10 compared to an inert reference electrode. The whole process meets the requirements of atomic economy and electric energy utilization in terms of sustainable chemical synthesis.

14.
J Geriatr Cardiol ; 18(4): 271-280, 2021 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-33995506

RESUMO

BACKGROUND: M1 polarization of macrophages is an important pathological process in myocardial ischemia reperfusion injury, which is the major obstacle for the treatment of acute myocardial infarction. Currently, the strategies and mechanisms of inhibiting M1 polarization are poorly explored. This study aims to investigate the role of soluble death receptor 5-Fc (sDR5-Fc) in regulating M1 polarization of macrophages under extreme conditions and explore the mechanisms from the aspect of glycolysis. METHODS: Extreme conditions were induced in RAW264.7 cells. Real-time quantitative polymerase chain reaction and western blot were used to detect the expression of mRNA and proteins, respectively. Cell counting kit-8 was used to investigate the proliferation activity of cells. Expression levels of inflammatory cytokines were determined by enzyme-linked immunosorbent assay. RESULTS: We found that sDR5-Fc rescues the proliferation of macrophages under extreme conditions, including nutrition deficiency, excessive peroxide, and ultraviolet irradiation. In addition, administration of sDR5-Fc inhibits the M1 polarization of macrophages induced by lipopolysaccharide (LPS) and interferon-gamma (IFN-γ), as the expression of M1 polarization markers CD86, CXC motif chemokine ligand 10, matrix metalloproteinase 9, and tumor necrosis factor-α, as well as the secretion of inflammatory factors interleukin (IL)-1ß and IL-6, were significantly decreased. By further investigation of the mechanisms, the results showed that sDR5-Fc can recover the LPS and IFN-γ induced pH reduction, lactic acid elevation, and increased expression of hexokinase 2 and glucose transporter 1, which were markers of glycolysis in macrophages. CONCLUSIONS: sDR5-Fc inhibits the M1 polarization of macrophages by blocking the glycolysis, which provides a new direction for the development of strategies in the treatment of myocardial ischemia reperfusion injury.

15.
Proc Natl Acad Sci U S A ; 118(20)2021 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-33972450

RESUMO

Industrial activity away from plate boundaries can induce earthquakes and has evolved into a global issue. Much of the induced seismicity in the United States' midcontinent is attributed to a direct pressure increase from deep wastewater disposal. This mechanism is not applicable where deep basement faults are hydraulically isolated from shallow injection aquifers, leading to a debate about the mechanisms for induced seismicity. Here, we compile industrial, seismic, geodetic, and geological data within the Delaware Basin, western Texas, and calculate stress and pressure changes at seismogenic depth using a coupled poroelastic model. We show that the widespread deep seismicity is mainly driven by shallow wastewater injection through the transmission of poroelastic stresses assuming that unfractured shales are hydraulic barriers over decadal time scales. A zone of seismic quiescence to the north, where injection-induced stress changes would promote seismicity, suggests a regional tectonic control on the occurrence of induced earthquakes. Comparing the poroelastic responses from injection and extraction operations, we find that the basement stress is most sensitive to shallow reservoir hydrogeological parameters, particularly hydraulic diffusivity. These results demonstrate that intraplate seismicity can be caused by shallow human activities that poroelastically perturb stresses at hydraulically isolated seismogenic depths, with impacts on seismicity that are preconditioned by regional tectonics.

17.
Chem Commun (Camb) ; 57(6): 741-744, 2021 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-33346273

RESUMO

Stille cross-coupling reactions catalysed by an ideal catalyst combining the high activity of homogeneous catalysts and the reusability of heterogeneous catalysts are of great interest for C-C bond formation, which is a widely used reaction in fine chemistry. Despite great effort to increase the utilization ratio of surface metal atoms, the activity of heterogeneous catalysts under mild conditions remains unsatisfactory. Herein, we design a proof-of-concept strategy to trigger the room-temperature activity of heterogeneous Au catalysts by decreasing the electron density at the interface of a rationally designed Schottky heterojunction of Au metals and boron-doped carbons. The electron-deficient Au nanoparticles formed as a result of the rectifying contact with boron-doped carbons facilitate the autocleavage of C-Br bonds for highly efficient C-C coupling reactions of alkylbromides and allylstannanes with a TOF value of 5199 h-1 at room temperature, surpassing that of the state-of-the-art homogeneous catalyst.

18.
Chem Commun (Camb) ; 56(83): 12566-12569, 2020 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-32940264

RESUMO

A stable artificial solid electrolyte interphase (ASEI) containing phosphazene and perfluoroalkoxy groups was designed to protect Li anodes. The ASEI with high ionic conductivity and mechanical robustness successfully suppressed the growth of Li dendrites, significantly enhancing the electrochemical performance of the Li-O2 batteries.

19.
Zhongguo Zhong Yao Za Zhi ; 45(15): 3565-3574, 2020 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-32893545

RESUMO

Quercetin is a kind of typical flavonoid, mainly found in various vegetables, fruits and Chinese herbs that are consumed daily, with the functions of anti-oxidation, anti-tumor, prevention and treatment of cardiovascular and cerebrovascular diseases. Quercetin is a natural compound with defined anti-tumor activity. Due to its low bioavailability and poor water solubility, quercetin has limitations in clinical application. The quercetin derivatives with good solubility, high bioavailability, metabolic stability, and low toxicity have been obtained through modification of quercetin structure. In recent years, a large number of quercetin ethers, esters, complexes, C-4 carbonyloxy substituted derivatives, A,B-ring modified compounds and other derivatives have been synthesized and tested for in vitro anticancer activity. The quercetin derivatives with anti-tumor activity synthesized in the last 5 years were reviewed in this paper.


Assuntos
Neoplasias , Quercetina , Disponibilidade Biológica , Humanos , Oxirredução , Solubilidade
20.
Opt Express ; 27(21): 29838-29853, 2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31684240

RESUMO

A single-pixel compressive imaging technique that uses differential modulation based on the transformation of discrete orthogonal Krawtchouk moments is proposed. In this method, two sets of Krawtchouk basis patterns are used to differentially modulate the light source, then the Krawtchouk moments of the target object are acquired from the light intensities measured by a single-pixel detector. The target image is reconstructed by applying an inverse Krawtchouk moment transform represented in the matrix form. The proposed technique is verified by both computational simulations and laboratory experiments. The results show that this technique can retrieve an image from compressive measurements and the real-time reconstruction. The background noise can be removed by the differential measurement to realize the excellent image quality. Moreover, the proposed technique is especially suitable for the single-pixel imaging application that requires the extraction of the characteristics at the region-of-interest.

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