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1.
Chemistry ; 27(62): 15536-15544, 2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34431546

RESUMO

The photocatalytic reduction of CO2 into fuels offers the prospect for creating a new CO2 economy. Harnessing visible light-driven CO2 -to-CO reduction mediated by the long-lived triplet excited state of rhenium(I) tricarbonyl complexes is a challenging approach. We here develop a series of new mononuclear rhenium(I) tricarbonyl complexes (Re-1-Re-4) based on the imidazole-pyridine skeleton for photo-driven CO2 reduction. These catalysts are featured by combining pyridyl-imidazole with the aromatic ring and different pendant organic groups onto the N1 position of 1,3-imidazole unit, which display phosphorescence under Ar-saturated solution even at ambient conditions. By contrast, {Re[9-(pyren-1-yl)-10-(pyridin-2-yl)-9H-pyreno[4,5-d]imidazole)](CO)3 Cl} (Re-4) by introducing pyrene ring at the N1 position of pyrene-fused imidazole unit exhibits superior catalytic performance with a higher turnover number for CO (TONCO =124) and >99.9 % selectivity, primarily ascribed to the strong visible light-harvesting ability, long-lived triplet lifetimes (164.2 µs) and large reductive quenching constant. Moreover, the rhenium(I) tricarbonyl complexes derived from π-extended pyrene chromophore exhibit a long lifetime corresponding to its ligand-localized triplet state (3 IL) evidenced from spectroscopic investigations and DFT calculations.

2.
Sensors (Basel) ; 21(16)2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34450756

RESUMO

Colonoscopies reduce the incidence of colorectal cancer through early recognition and resecting of the colon polyps. However, the colon polyp miss detection rate is as high as 26% in conventional colonoscopy. The search for methods to decrease the polyp miss rate is nowadays a paramount task. A number of algorithms or systems have been developed to enhance polyp detection, but few are suitable for real-time detection or classification due to their limited computational ability. Recent studies indicate that the automated colon polyp detection system is developing at an astonishing speed. Real-time detection with classification is still a yet to be explored field. Newer image pattern recognition algorithms with convolutional neuro-network (CNN) transfer learning has shed light on this topic. We proposed a study using real-time colonoscopies with the CNN transfer learning approach. Several multi-class classifiers were trained and mAP ranged from 38% to 49%. Based on an Inception v2 model, a detector adopting a Faster R-CNN was trained. The mAP of the detector was 77%, which was an improvement of 35% compared to the same type of multi-class classifier. Therefore, our results indicated that the polyp detection model could attain a high accuracy, but the polyp type classification still leaves room for improvement.


Assuntos
Colonoscopia , Redes Neurais de Computação , Colo , Computadores , Aprendizado de Máquina
3.
J Org Chem ; 85(21): 14109-14120, 2020 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-33118350

RESUMO

Compounds bearing organophosphorus motifs and 2-oxazolidinone have found numerous applications in pharmaceutical chemistry, homogeneous catalysis, and organic materials. Here, we describe an efficient and selective protocol for straightforward access to a series of 5-((diarylphosphoryl)methyl)oxazolidin-2-ones via the copper-catalyzed difunctionalization of the C≡C bond of propargylic amines with CO2 and phosphine oxide. Notably, copper catalysis is a sustainable and benign catalytic mode. This reaction proceeds under mild reaction conditions, which is operationally simple and scalable with a broad scope, exclusive selectivity, and good functional group compatibility. Mechanistic studies suggest a one-pot tandem cyclization/radical addition sequence, along with the phosphorylation/cyclization scheme.

4.
Research (Wash D C) ; 2020: 9398285, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33063016

RESUMO

In the photoreduction of CO2 to CO, the competitive H2 evolution is always inevitable due to the approximate reduction potentials of H+/H2 and CO2/CO, which results in poor selectivity for CO production. Herein, imidazolium-type ionic liquid- (IL-) modified rhenium bipyridine-based porous organometallic polymers (Re-POMP-IL) were designed as efficient and selective photocatalysts for visible-light CO2 photoreduction to CO based on the affinity of IL with CO2. Photoreduction studies demonstrated that CO2 photoreduction promoted by Re-POMP-IL functioning as the catalyst exhibits excellent CO selectivity up to 95.5% and generate 40.1 mmol CO/g of Re-POMP-IL1.0 (obtained by providing equivalent [(5,5'-divinyl-2,2'-bipyridine)Re(CO)3Cl] and 3-ethyl-1-vinyl-1H-imidazol-3-ium bromide) at 12 h, outperforming that attained with the corresponding Re-POMP analogue without IL, which highlights the crucial role of IL. Notably, CO2 adsorption, light harvesting, and transfer of photogenerated charges as key steps for CO2RR were studied by employing POMPs modified with different amounts of IL as photocatalysts, among which the CO2 affinity as an important factor for POMPs catalyzed CO2 reduction is revealed. Overall, this work provides a practical pathway to improve the CO2 photoreduction efficiency and CO selectivity by employing IL as a regulator.

5.
ChemSusChem ; 13(23): 6284-6289, 2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-32311230

RESUMO

Developing an efficient and easy-to-handle strategy in designing catalysts for CO2 reduction into CO by harnessing sunlight is a promising project. Here, a facile strategy was developed to design a Re catalyst modified with an ionic secondary coordination sphere for photoreduction of CO2 to CO by visible light. By adding ionic liquids or tuning a different ionic secondary coordination sphere, it was discovered that an outstanding optical property, other than CO2 absorption ability or the ability to dissociation of chloride anion, is the prerequisite for catalyst design. Accordingly, a novel Re catalyst, {Re[BpyMe(tris(2-hydroxyethyl)amine)](CO)3 Cl}Br (Re-THEA), was designed, screened, and resulted in a relative high quantum yield (up to 34 %) for visible-light-induced CO2 reduction with a single-molecule system. DFT calculations, combined with experimental outcomes, suggested the pendant ionic tris(2-hydroxyethyl)amino (THEA) group on Re-THEA can enhance visible-light absorption, stabilize reaction intermediates, and suppress the Re-Re dimer formation.

6.
ChemSusChem ; 12(23): 5081-5085, 2019 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-31671246

RESUMO

A visible-light-promoted metal-free carboxylative cyclization of propargylic amines with CO2 was shown to offer exo-iodomethylene 2-oxazolidinones. Incorporation of both CO2 and iodo moieties into these compounds was realized efficiently. The mechanism study revealed that this carboxylative cyclization proceeds through a radical pathway. Notably, the iodine-functionalized 2-oxazolidinone as a platform molecule could be easily converted into a wide range of value-added chemicals through Buchwald-Hartwig, Suzuki, Sonogashira, photocatalytic ene, and photoreduction reactions. As a result, the plentiful downstream transformations remarkably enhance the range of chemicals derived from CO2 and open a potential avenue for CO2 functionalization to circumvent energy challenges in this field.

7.
Front Chem ; 6: 462, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30349815

RESUMO

Carbon dioxide, as a promising C1 synthon, has attracted great interest in organic synthesis. Due to the thermodynamic stability and kinetic inertness of CO2, developing efficient strategies for CO2 activation and subsequent conversion is very crucial. In this context, Ionic liquids (ILs) show great potential for capturing and activating CO2 owing to their unique structures and properties, making them become ideal alternatives to volatile organic solvents and/or catalysts for CO2 transformation. This minireview aims at summarizing ILs-promoted reactions of CO2 with N-nucleophiles (primary amines)/O-nucleophiles (primary alcohols, water). Two catalytic systems i.e., metal/ILs binary systems such as Cu/ILs systems and Ag/ILs systems as well as single ILs systems including anion-functionalized ILs and bifunctionalized ILs have been developed for CO2 catalytic conversion, for instance, carboxylative cyclization of nucleophiles e.g., propargylic alcohols, amines, 2-aminobenzonitriles and o-aminobenzenethiol, and formylation of amines or 2-aminothiophenols with hydrosilanes to afford various value-added chemicals e.g., cyclic carbamates, unsymmetrical organic carbonates, α-hydroxyl ketones, and benzimidazolones. In a word, IL could provide a powerful tool for efficient CO2 utilization.

9.
Comput Methods Programs Biomed ; 144: 37-48, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28495005

RESUMO

BACKGROUND AND OBJECTIVE: Self-management in healthcare can allow patients managing their health data anytime and everywhere for prevention of chronic diseases. This study established a prototype of ubiquitous health management system (UHMS) with healthy diet control (HDC) for people who need services of metabolic syndrome healthcare in Taiwan. METHODS: System infrastructure comprises of three portals and a database tier with mutually supportive components to achieve functionality of diet diaries, nutrition guides, and health risk assessments for self-health management. With the diet, nutrition, and personal health database, the design enables the analytical diagrams on the interactive interface to support a mobile application for diet diary, a Web-based platform for health management, and the modules of research and development for medical care. For database integrity, dietary data can be stored at offline mode prior to transformation between mobile device and server site at online mode. RESULTS: The UHMS-HDC was developed by open source technology for ubiquitous health management with personalized dietary criteria. The system integrates mobile, internet, and electronic healthcare services with the diet diary functions to manage healthy diet behaviors of users. The virtual patients were involved to simulate the self-health management procedure. The assessment functions were approved by capturing the screen snapshots in the procedure. The proposed system development was capable for practical intervention. CONCLUSION: This approach details the expandable framework with collaborative components regarding the self-developed UHMS-HDC. The multi-disciplinary applications for self-health management can support the healthcare professionals to reduce medical resources and improve healthcare effects for the patient who requires monitoring personal health condition with diet control. The proposed system can be practiced for intervention in the hospital.


Assuntos
Dieta Saudável , Promoção da Saúde/métodos , Síndrome Metabólica/dietoterapia , Aplicativos Móveis , Autocuidado , Registros de Dieta , Humanos , Internet , Taiwan
10.
Medicine (Baltimore) ; 96(10): e6259, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28272231

RESUMO

The potential value of N-terminal pro-brain natriuretic peptide (NT-proBNP) for contrast-induced acute kidney injury (CI-AKI) in patients with heart failure and mid-range ejection fraction (HFmrEF) is unclear. We investigated whether NT-proBNP is associated with CI-AKI and long-term mortality following elective cardiac catheterization in patients with HFmrEF.A total of 174 consecutive patients with HFmrEF undergoing elective coronary angiography or intervention were enrolled. The primary endpoint was the development of CI-AKI, defined as an absolute increase of ≥0.3 mg/dL or ≥ 50% from baseline serum creatinine with 48 hours after contrast medium exposure. Receiver-operating characteristic curve analysis was conducted, and Youden index was used to determine the best cutoff NT-proBNP value. Multivariable logistic regression and Cox proportional hazards regression analyses were performed to identify the independent risk factors for CI-AKI and long-term mortality, respectively.The incidence of CI-AKI was 12.1%. Patients with CI-AKI had higher NT-proBNP values than those without (4373[1561.9-7470.5] vs 1303[625.2-2482.3], P = 0.003). Receiver-operating characteristic curve revealed that NT-proBNP was not significantly different from the Mehran risk score in predicting CI-AKI (area under the curve [AUC] = 0.723 vs 0.767, P = 0.516). The best cutoff NT-proBNP value for CI-AKI was 3299 pg/mL, with 70.6% sensitivity and 83.1% specificity. Multivariable analysis demonstrated that NT-proBNP ≥3299 pg/mL is significantly related to CI-AKI (odds ratio = 12.79; 95% confidence interval, 3.18-51.49; P < 0.001). Cox regression analysis showed that NT-proBNP ≥3299 pg/mL is associated with long-term mortality (adjusted hazard ratio = 11.91; 95%CI, 2.16-65.70; P = 0.004) during follow-up.In patients with HFmrEF, NT-proBNP ≥3299 pg/mL is associated with CI-AKI and long-term mortality following elective coronary angiography or intervention.


Assuntos
Injúria Renal Aguda/sangue , Injúria Renal Aguda/induzido quimicamente , Insuficiência Cardíaca/complicações , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Injúria Renal Aguda/mortalidade , Idoso , Cateterismo Cardíaco , China/epidemiologia , Feminino , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Volume Sistólico
11.
Oncotarget ; 8(65): 109762-109771, 2017 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-29312646

RESUMO

OBJECTIVE: To investigate the predictive value of post-procedural early (within 24 h) increase in cystatin C for contrast-induced acute kidney injury (CI-AKI) and all-cause mortality following coronary angiography or intervention. METHODS: We prospectively investigated 1042 consecutive patients with both baseline and early post-procedural cystatin C measurement undergoing coronary angiography or intervention. CI-AKI was defined as an increase ≥0.3 mg/dL or >50% in serum creatinine from baseline within 48 h post-procedure. Mean follow-up was 2.26 years. RESULTS: Overall, the patients had a CI-AKI incidence was 3.6% (38/1042), mean serum creatinine of 87 µmol/L. Compared with Mehran risk score, post-procedural early absolute increase (AUC: 0.584 vs. 0.706, P = 0.060) and relative increase (AUC: 0.585 vs. 0.706, P = 0.058) in cystatin C had poorer predictive value for CI-AKI. According to multivariate analysis, post-procedural significant early increase (≥0.3 mg/dL or ≥10%) in cystatin C developed in 231 patients (22.2%), was not independent predictor of CI-AKI (adjusted OR: 1.23, 95% CI, 0.56-2.69, P = 0.612), and long-term mortality (adjusted HR: 0.90; P = 0.838). CONCLUSIONS: Our data suggested post-procedural early increase (within 24 h) in cystatin C was not effective for predicting CI-AKI or all-cause mortality following coronary angiography or intervention among patients at relative low risk of CI-AKI, the negative finding of poor predictive value should be further evaluated in larger multicenter trials.

12.
Gene ; 592(1): 43-48, 2016 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-27425867

RESUMO

Atherosclerosis is a chronic disease of the arterial wall and a leading cause of death worldwide. Though the pathophysiology of atherosclerotic lesion formation has been studied, we still lack evidence of the global changes in the artery during atherosclerosis. In this report, we induced atherosclerosis in rats and conducted GeneChip analysis on carotid arteries with or without plaque formation. We found that molecular pathways underlying plaque formation in atherosclerosis were related to immune response, angiogenesis, cell proliferation, apoptosis and hypoxic microenvironments, suggesting that the pathophysiology of atherosclerosis is varied. In addition, we showed that three lncRNAs, GAS5, SNHG6 and Zfas1, were significantly increased in the plaque of atherosclerosis patients compared to normal people. A complex interaction of mRNA and lncRNA was identified in atherosclerosis. Our results provide a global transcriptomic network of atherosclerosis development in rats and possible targets that could lead to new clinical applications in the future.


Assuntos
Aterosclerose/genética , Transcriptoma , Animais , Masculino , RNA Longo não Codificante/genética , Ratos , Ratos Sprague-Dawley
13.
Zhonghua Nan Ke Xue ; 22(2): 175-9, 2016 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-26939405

RESUMO

The G protein-coupled estrogen receptor (GPER), also known as G protein-coupled receptor 30 (GPR30), was identified in the recent years as a functional membrane receptor different from the classical nuclear estrogen receptors. This receptor is widely expressed in the cortex, cerebellum, hippocampus, heart, lung, liver, skeletal muscle, and the urogenital system. It is responsible for the mediation of nongenomic effects associated with estrogen and its derivatives, participating in the physiological activities of the body. The present study reviews the molecular structure, subcellular localization, signaling pathways, distribution, and function of GPER in the male reproductive system.


Assuntos
Genitália Masculina/metabolismo , Receptores de Estrogênio/fisiologia , Receptores Acoplados a Proteínas G/fisiologia , Reprodução/fisiologia , Estrogênios/metabolismo , Humanos , Masculino , Estrutura Molecular , Especificidade de Órgãos , Receptores de Estrogênio/química , Receptores Acoplados a Proteínas G/química , Transdução de Sinais
14.
Int J Clin Exp Pathol ; 8(6): 7217-22, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26261617

RESUMO

Recent evidence suggested a positive correlation between environmental estrogens (EEs) and high incidence of abnormalities in male urogenital system. EEs are known to cause the abnormalities of testes development and testicular descent. Diethylstilbestrol (DES) is a nonsteroidal synthetic estrogen that disrupts the morphology and proliferation of gubernacular cells, and its nongenomic effects on gubernaculum testis cells may be mediated by G protein-coupled estrogen receptor (GPER). In this study, we detected the expression of GPER in mouse gubernacular testis and investigated the effects of DES on the expression of GPER in gubernaculum testis cells. RT-PCR analysis revealed that GPER mRNA was expressed in the gubernaculum. GPER protein was detected in the parenchymal cells of the gubernaculum early in development. Furthermore, we demonstrate that GPER inhibitor G15 relieved DES-induced inhibition of GPER expression in gubernaculum testis cell, but ER inhibitor ICI 182780 had the converse effects on DES-induced inhibition of GPER expression in these cells. These data suggest that the effects of DES on mouse gubernaculum testis cells are mediated at least partially by the regulation of GPER expression.


Assuntos
Dietilestilbestrol/toxicidade , Disruptores Endócrinos/toxicidade , Receptores de Estrogênio/efeitos dos fármacos , Receptores Acoplados a Proteínas G/efeitos dos fármacos , Testículo/efeitos dos fármacos , Animais , Benzodioxóis/farmacologia , Células Cultivadas , Estradiol/análogos & derivados , Estradiol/farmacologia , Antagonistas do Receptor de Estrogênio/farmacologia , Fulvestranto , Regulação da Expressão Gênica , Masculino , Camundongos , Quinolinas/farmacologia , RNA Mensageiro/metabolismo , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Testículo/metabolismo , Testículo/patologia , Fatores de Tempo
15.
J Thorac Dis ; 6(9): E169-72, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25276390

RESUMO

A 22-year-old young man with a history of idiopathic dilated cardiomyopathy (IDC) was admitted to our hospital due to difficult-to-control heart failure. A thoracic X-ray showed multiple nodules at the both pulmonary hilus and upper lobe of the right lung. Computed tomography (CT) angiography of the thorax confirmed arteriovenous malformation (AVM). However, effective treatment was impossible due to the poor physical condition; he died a few days later. Here we reported on the case of pulmonary arteriovenous malformations (PAVMs) being misdiagnosed as refractory heart failure.

16.
Phys Chem Chem Phys ; 14(45): 15832-9, 2012 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-23090138

RESUMO

Up to now, flue-gas desulfurization (FGD) is one of the most effective techniques to control SO(2) emission from the combustion of fossil fuels. The conventional technology for FGD poses serious inherent drawbacks such as formation of byproducts and volatilization of solvents. In this work, polyethylene glycol (PEG)-functionalized Lewis basic ionic liquids (ILs) derived from DABCO were proved to be highly efficient absorbents for FGD due to its specific features such as high thermal stability, negligible vapor pressure, high loading capacity. Notably, PEG(150)MeDABCONTf(2) gave an extremely high SO(2) capacity (4.38 mol mol(-1) IL), even under 0.1 bar SO(2) partial pressure (1.01 mol mol(-1) IL), presumably owing to the strong SO(2)-philic characterization of the PEG chain. Furthermore, the absorbed SO(2) could be easy to release by just bubbling N(2) at room temperature, greatly reducing energy requirement for SO(2) desorption. In addition, SO(2)/CO(2) selectivity (110) of PEG(150)MeDABCONTf(2) is two times larger than the non-functionalized imidazolium IL (45). On the other hand, through activation of SO(2) with the tertiary nitrogen in the cation, Lewis basic ILs such as PEG(150)MeDABCOBr proved to be efficient catalysts for the conversion of SO(2) to some value-added chemicals such as cyclic sulfites without utilization of any organic solvent or additive. Thus, this protocol would pave the way for the development of technological innovation towards efficient and low energy demanded practical process for SO(2) absorption and subsequent transformation.


Assuntos
Líquidos Iônicos/química , Polietilenoglicóis/química , Dióxido de Enxofre/química , Estrutura Molecular , Sulfitos/síntese química , Sulfitos/química
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