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1.
Phytomedicine ; 127: 155487, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38490078

RESUMO

AIM: To extend and form the "Grading of Recommendations Assessment, Development and Evaluation in Traditional Chinese Medicine" (GRADE-TCM). METHODS: Methodologies were systematically reviewed and analyzed concerning evidence-based TCM guidelines worldwide. A survey questionnaire was developed based on the literature review and open-end expert interviews. Then, we performed expert consensus, discussion meeting, opinion collection, external examination, and the GRADE-TCM was formed eventually. RESULTS: 265 Chinese and English TCM guidelines were included and analyzed. Five experts completed the open-end interviews. Ten methodological entries were summarized, screened and selected. One round of consensus was conducted, including a total of 22 experts and 220 valid questionnaire entries, concerning 1) selection of the GRADE, 2) GRADE-TCM upgrading criteria, 3) GRADE-TCM evaluation standard, 4) principles of consensus and recommendation, and 5) presentation of the GRADE-TCM and recommendation. Finally, consensus was reached on the above 10 entries, and the results were of high importance (with voting percentages ranging from 50 % to 81.82 % for "very important" rating) and strong reliability (with the Cr ranging from 0.93 to 0.99). Expert discussion meeting (with 40 experts), opinion collection (in two online platforms) and external examination (with 14 third-party experts) were conducted, and the GRADE-TCM was established eventually. CONCLUSION: GRADE-TCM provides a new extended evidence-based evaluation standard for TCM guidelines. In GRADE-TCM, international evidence-based norms, characteristics of TCM intervention, and inheritance of TCM culture were combined organically and followed. This is helpful for localization of the GRADE in TCM and internationalization of TCM guidelines.


Assuntos
Medicina Baseada em Evidências , Medicina Tradicional Chinesa , Humanos , Medicina Tradicional Chinesa/métodos , Reprodutibilidade dos Testes , Inquéritos e Questionários , Povo Asiático
2.
Abdom Radiol (NY) ; 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38472310

RESUMO

PURPOSE: To evaluate and compare the diagnostic performances of whole-lesion iodine map (IM) histogram analysis and single-slice IM measurement in the risk classification of gastrointestinal stromal tumors (GISTs). METHODS: Thirty-seven patients with GISTs, including 19 with low malignant underlying GISTs (LG-GISTs) and 18 with high malignant underlying GISTs (HG-GISTs), were evaluated with dual-energy computed tomography (DECT). Whole-lesion IM histogram parameters (mean; median; minimum; maximum; standard deviation; variance; 1st, 10th, 25th, 50th, 75th, 90th, and 99th percentile; kurtosis, skewness, and entropy) were computed for each lesion. In other sessions, iodine concentrations (ICs) were derived from the IM by placing regions of interest (ROIs) on the tumor slices and normalizing them to the iodine concentration in the aorta. Both quantitative analyses were performed on the venous phase images. The diagnostic accuracies of the two methods were assessed and compared. RESULTS: The minimum, maximum, 1st, 10th, and 25th percentile of the whole-lesion IM histogram and the IC and normalized IC (NIC) of the single-slice IC measurement significantly differed between LG- and HG-GISTs (p < 0.001 - p = 0.042). The minimum value in the histogram analysis (AUC = 0.844) and the NIC in the single-slice measurement analysis (AUC = 0.886) showed the best diagnostic performances. The NIC of single-slice measurements had a diagnostic performance similar to that of the whole-lesion IM histogram analysis (p = 0.618). CONCLUSIONS: Both whole-lesion IM histogram analysis and single-slice IC measurement can differentiate LG-GISTs and HG-GISTs with similar diagnostic performances.

3.
Sci Rep ; 14(1): 5566, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38448463

RESUMO

The micro-scale gas adsorption-desorption characteristics determine the macro-scale gas transport and production behavior. To reveal the three-dimensional stress state-induced gas adsorption-desorption characteristics in coal-bearing shale reservoirs from a micro-scale perspective, the coal-bearing shale samples from the Dongbaowei Coal Mine in the Shuangyashan Basin were chosen as the research subject. Isothermal adsorption-desorption experiments under three-dimensional stress state were conducted using the low field nuclear magnetic resonance (L-NMR) T2 spectrum method to simulate the in-situ coal-bearing shale gas adsorption-desorption process. The average effective stress was used as the equivalent stress indicator for coal-bearing shale, and the integral of nuclear magnetic resonance T2 spectrum amplitude was employed as the gas characterization indicator for coal-bearing shale. A quantitative analysis was performed to examine the relationship between gas adsorption in coal-bearing shale and the average effective stress. And a quantitative analysis was performed to examine the relationship between the macroscopic and microscopic gas quantities of coal-bearing shale. Experimental findings: (1) The adsorption-desorption process of coal-bearing shale gas follows the L-F function model and the D-A-d function model respectively with respect to the amount of gas and the average effective stress. (2) There is a logarithmic relationship between the macroscopic and microscopic gas quantities of coal-bearing shale during the adsorption-desorption process. This quantitatively characterizes the differences in the curves, which may be related to the elastic-plastic deformation, damage and fracture of the micropores in coal-bearing shale, as well as the hysteresis of gas desorption and the stress field of the gas occurrence state.

4.
ChemSusChem ; : e202301719, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38411399

RESUMO

The electroreduction of CO2 to high-value products is a promising approach for achieving carbon neutrality. Among these products, formic acid stands out as having the most potential for industrialization due to its optimal economic value in terms of consumption and output. In recent years, the Faraday efficiency of formic acid from CO2 electroreduction has reached 90~100 %. However, this high selectivity cannot be maintained for extended periods under high currents to meet industrial requirements. This paper reviews excellent work from the perspective of catalyst stability, summarizing and discussing the performance of typical catalysts. Strategies for preparing stable and highly active catalysts are also briefly described. This review may offer a useful data reference and valuable guidance for the future design of long-stability catalysts.

5.
Biomed Opt Express ; 15(2): 506-523, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38404328

RESUMO

As endoscopic imaging technology advances, there is a growing clinical demand for enhanced imaging capabilities. Although conventional white light imaging (WLI) endoscopy offers realistic images, it often cannot reveal detailed characteristics of the mucosa. On the other hand, optical staining endoscopy, such as Compound Band Imaging (CBI), can discern subtle structures, serving to some extent as an optical biopsy. However, its image brightness is low, and the colors can be abrupt. These two techniques, commonly used in clinical settings, have complementary advantages. Nonetheless, they require different lighting conditions, which makes it challenging to combine their imaging strengths on living tissues. In this study, we introduce a novel endoscopic imaging technique that effectively combines the advantages of both WLI and CBI. Doctors don't need to manually switch between these two observation modes, as they can obtain the image information of both modes in one image. We calibrated an appropriate proportion for simultaneous illumination with the light required for WLI and CBI. We designed a new illumination spectrum tailored for gastrointestinal examination, achieving their fusion at the optical level. Using a new algorithm that focuses on enhancing specific hemoglobin tissue features, we restored narrow-band image characteristics lost due to the introduction of white light. Our hardware and software innovations not only boost the illumination brightness of the endoscope but also ensure the narrow-band feature details of the image. To evaluate the reliability and safety of the new endoscopic system, we conducted a series of tests in line with relevant international standards and validated the design parameters. For clinical trials, we collected a total of 256 sets of images, each set comprising images of the same lesion location captured using WLI, CBI, and our proposed method. We recruited four experienced clinicians to conduct subjective evaluations of the collected images. The results affirmed the significant advantages of our method. We believe that the novel endoscopic system we introduced has vast potential for clinical application in the future.

6.
Chemistry ; 30(25): e202303989, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38345999

RESUMO

Benzobicyclo[3.2.1]octane is a cage-like unique motif containing a bicyclo[3.2.1]octane structure fused with at least one benzene ring. It is found in various natural products that exhibit structural complexities and important biological activities. The total synthesis of natural products possessing this challenging structure has received considerable attention, and great advances have been made in this field during the past 15 years. This review summarizes thus far achieved chemical syntheses and synthetic studies of natural compounds featuring the benzobicyclo[3.2.1]octane core. It focuses on strategic approaches constructing the bridged structure, aiming to provide a useful reference for inspiring further advancements in strategies and total syntheses of natural products with such a framework.

7.
J Am Chem Soc ; 146(7): 4433-4443, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38329948

RESUMO

Potassium-sulfur (K-S) batteries are severely limited by the sluggish kinetics of the solid-phase conversion of K2S3/K2S2 to K2S, the rate-determining and performance-governing step, which urgently requires a cathode with facilitated sulfur accommodation and improved catalytic efficiency. To this end, we leverage the orbital-coupling approach and herein report a strong d-π coupling catalytic configuration of single-atom Co anchored between two alkynyls of graphdiyne (Co-GDY). The d-π orbital coupling of the Co-C4 moiety fully redistributes electrons two-dimensionally across the GDY, and as a result, drastically accelerates the solid-phase K2S3/K2S2 to K2S conversion and enhances the adsorption of sulfur species. Applied as the cathode, the S/Co-GDY delivered a record-high rate performance of 496.0 mAh g-1 at 5 A g-1 in K-S batteries. In situ and ex situ characterizations coupling density functional theory (DFT) calculations rationalize how the strong d-π orbital coupling of Co-C4 configuration promotes the reversible solid-state transformation kinetics of potassium polysulfide for high-performance K-S batteries.

8.
Angew Chem Int Ed Engl ; 63(11): e202319108, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38196079

RESUMO

Engineering isolated metal sites resembling the primary coordination sphere of metallocofactors enables atomically dispersed materials as promising nanozymes. However, most existing nanozymes primarily focus on replicating specific metallocofactors while neglecting other supporting cofactors within active pockets, leading to reduced electron transfer (ET) efficiency and thus inferior catalytic performances. Herein, we report a metal-organic framework UiO-67 nanozyme with atomically dispersed iron sites, which involves multiple tailored enzyme-like nanocofactors that synergistically drive the ET process for enhanced peroxidase-like catalysis. Among them, the linker-coupled atomic iron site plays a critical role in substrate activation, while bare linkers and zirconia nodes facilitate the ET efficiency of intermediates. The synergy of three nanocofactors results in a 4.29-fold enhancement compared with the single effort of isolated metal site-based nanocofactor, holding promise in immunoassay for sensitive detection of chlorpyrifos. This finding opens a new way for designing high-performance nanozymes by harmonizing various nanocofactors at the atomic and molecular scale.


Assuntos
Oxirredutases , Peroxidase , Peroxidases , Ferro/química , Catálise
9.
Small ; : e2310469, 2024 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-38282141

RESUMO

Water splitting (or, water electrolysis) is considered as a promising approach to produce green hydrogen and relieve the ever-increasing energy consumption as well as the accompanied environmental impact. Development of high-efficiency, low-cost practical water-splitting systems demands elegant design and fabrication of catalyst-loaded electrodes with both high activity and long-life time. To this end, dimensional engineering strategies, which effectively tune the microstructure and activity of electrodes as well as the electrochemical kinetics, play an important role and have been extensively reported over the past years. Here, a type of most investigated electrode configurations is reviewed, combining particulate catalysts with 3D porous substrates (aerogels, metal foams, hydrogels, etc.), which offer special advantages in the field of water splitting. It is analyzed the design principles, structural and interfacial characteristics, and performance of particle-3D substrate electrode systems including overpotential, cycle life, and the underlying mechanism toward improved catalytic properties. In particular, it is also categorized the catalysts as different dimensional particles, and show the importance of building hybrid composite electrodes by dimensional control and engineering. Finally, present challenges and possible research directions toward low-cost high-efficiency water splitting and hydrogen production is discussed.

10.
Int J Comput Assist Radiol Surg ; 19(2): 331-344, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37603164

RESUMO

PURPOSE: White light imaging (WLI) is a commonly seen examination mode in endoscopy. The particular light in compound band imaging (CBI) can highlight delicate structures, such as capillaries and tiny structures on the mucosal surface. These two modes complement each other, and doctors switch between them manually to complete the examination. This paper proposes an endoscopy image fusion system to combine WLI and CBI. METHODS: We add a real-time rotatable color wheel in the light source device of the AQ-200 endoscopy system to achieve rapid imaging of two modes at the same position of living tissue. The two images corresponding to the pixel level can avoid registration and lay the foundation for image fusion. We propose a multi-scale image fusion framework, which involves Laplacian pyramid (LP) and convolutional sparse representation (CSR) and strengthens the details in the fusion rule. RESULTS: Volunteer experiments and ex vivo pig stomach trials are conducted to verify the feasibility of our proposed system. We also conduct comparative experiments with other image fusion methods, evaluate the quality of the fused images, and verify the effectiveness of our fusion framework. The results show that our fused image has rich details, high color contrast, apparent structures, and clear lesion boundaries. CONCLUSION: An endoscopy image fusion system is proposed, which does not change the doctor's operation and makes the fusion of WLI and CBI optical staining technology a reality. We change the light source device of the endoscope, propose an image fusion framework, and verify the feasibility and effectiveness of our scheme. Our method fully integrates the advantages of WLI and CBI, which can help doctors make more accurate judgments than before. The endoscopy image fusion system is of great significance for improving the detection rate of early lesions and has broad application prospects.


Assuntos
Endoscopia Gastrointestinal , Endoscopia , Humanos , Animais , Suínos , Luz , Imagem de Banda Estreita/métodos
11.
J Colloid Interface Sci ; 658: 137-147, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38100970

RESUMO

Hydrogel-based functional materials had attracted great attention in the fields of artificial intelligence, soft robotics, and motion monitoring. However, the gelation of hydrogels induced by free radical polymerization typically required heating, light exposure, and other conditions, limiting their practical applications and development in real-life scenarios. In this study, a simple and direct method was proposed to achieve rapid gelation at room temperature by incorporating reductive MXene sheets in conjunction with metal ions into the chitosan network and inducing the formation of a polyacrylamide network in an extremely short time (10 s). This resulted in a dual-network MXene-crosslinked conductive hydrogel composite that exhibited exceptional stretchability (1350 %), remarkably low dissipated energy (0.40 kJ m-3 at 100 % strain), high sensitivity (GF = 2.86 at 300-500 % strain), and strong adhesion to various substrate surfaces. The study demonstrated potential applications in the reliable detection of various motions, including repetitive fine movements and large-scale human body motions. This work provided a feasible platform for developing integrated wearable health-monitoring electronic systems.


Assuntos
Quitosana , Nitritos , Elementos de Transição , Dispositivos Eletrônicos Vestíveis , Humanos , Hidrogéis , Inteligência Artificial , Condutividade Elétrica
12.
Nat Commun ; 14(1): 6064, 2023 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-37770453

RESUMO

Neurotoxicity of organophosphate compounds (OPs) can catastrophically cause nervous system injury by inhibiting acetylcholinesterase (AChE) expression. Although artificial systems have been developed for indirect neuroprotection, they are limited to dissociating P-O bonds for eliminating OPs. However, these systems have failed to overcome the deactivation of AChE. Herein, we report our finding that Al3+ is engineered onto the nodes of metal-organic framework to synthesize MOF-808-Al with enhanced Lewis acidity. The resultant MOF-808-Al efficiently mimics the catalytic behavior of AChE and has a self-defense ability to break the activity inhibition by OPs. Mechanism investigations elucidate that Al3+ Lewis acid sites with a strong polarization effect unite the highly electronegative -OH groups to form the enzyme-like catalytic center, resulting in superior substrate activation and nucleophilic attack ability with a 2.7-fold activity improvement. The multifunctional MOF-808-Al, which has satisfactory biosafety, is efficient in reducing neurotoxic effects and preventing neuronal tissue damage.


Assuntos
Acetilcolinesterase , Biomimética , Acetilcolinesterase/química , Neuroproteção , Organofosfatos
13.
J Am Chem Soc ; 145(39): 21432-21441, 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37728051

RESUMO

Although dispersing Pt atomic clusters (ACs) on a conducting support is a promising way to minimize the Pt amount required in hydrogen evolution reaction (HER), the catalytic mass activity and durability of Pt ACs are often unsatisfactory for alkaline HER due to their unfavorable water dissociation and challenges in stabilizing them against agglomeration and detachment. Herein, we report a class of single-atom Cr-N4 sites with high oxophilicity interfaced with Pt ACs on mesoporous carbon for achieving a highly active and stable alkaline HER in an anion-exchange-membrane water electrolyzer (AEMWE). The as-made catalyst achieves the highest reported Pt mass activity (37.6 times higher than commercial Pt/C) and outstanding operational stability. Experimental and theoretical studies elucidate that the formation of a unique Pt-Cr quasi-covalent bonding interaction at the interface of Cr-N4 sites and Pt ACs effectively suppresses the migration and thermal vibration of Pt atoms to stabilize Pt ACs and contributes to the greatly enhanced catalytic stability. Moreover, oxophilic Cr-N4 sites adjacent to Pt ACs with favorable adsorption of hydroxyl species facilitate nearly barrierless water dissociation and thus enhance the HER activity. An AEMWE using this catalyst (with only 50 µgPt cm-2) can operate stably at an industrial-level current density of 500 mA cm-2 at 1.8 V for >100 h with a small degradation rate of 90 µV h-1.

14.
Hum Vaccin Immunother ; 19(2): 2236538, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37530139

RESUMO

To evaluated the risk ratio of Allergic rhinitis (AR) people on the symptoms after COVID-19 infection, and explored the relationship between AR and the symptoms after COVID-19 infection. An observational study was performed of people from outpatient department of the Hospital of Chengdu University of Chinese Medicine. Participants completed an electronic survey and between January 10 to January 20, 2023. We divided the participants into three groups according to the disease information of the population: non-AR people group (AR-N), AR patients with sublingual immunotherapy group (AR-S), and AR patients with conventional therapy group (AR-C). A total of 1116 participants were included in the study, with an average age of 21.76 ± 8.713, women accounted for 62.5%, men accounted for 37.5%. The final results showed that the risk of most symptoms after AR-C infection was not different from that of AR-N, except for sore throat, dry and itchy, chest distress, shortness of breath, and dyspnea. AR-S could effectively reduce the risk of post-infection symptoms including: dry and itchy (OR = 0.484, 95%CI: 0.335-0.698), pain (OR = 0.513, 95%CI:0.362-0.728), cough (OR = 0.506, 95% CI:0.341-0.749), expectoration (OR = 0.349, 95% CI:0.244-0.498), fever (OR = 0.569, 95% CI:0.379-0.853), head and body pain (OR = 0.456, 95% CI:0.323-0.644), fatigue (OR = 0.256, 95% CI:0.177-0.371), cold limbs (OR = 0.325, 95%CI:0.227-0.465), diarrhea (OR = 0.246, 95% CI:0.132-0.457), constipation (OR = 0.227, 95%CI:0.100-0.513), hyposmia (OR = 0.456, 95% CI:0.296-0.701), hypogeusia (OR = 0.397, 95% CI:0.259-0.607), chest distress (OR = 0.534, 95% CI:0.343-0.829), shortness of breath (OR = 0.622, 95% CI:0.398-0.974), palpitations (OR = 0.355, 95% CI:0.206-0.613). The risk of symptoms after COVID-19 infection in allergic rhinitis population receiving sublingual immunotherapy is lower.


Assuntos
COVID-19 , Rinite Alérgica , Imunoterapia Sublingual , Masculino , Humanos , Feminino , Adolescente , Adulto Jovem , Adulto , Imunoterapia Sublingual/efeitos adversos , Imunoterapia Sublingual/métodos , COVID-19/terapia , Rinite Alérgica/terapia , Dispneia/etiologia , Dor/etiologia
15.
Front Pediatr ; 11: 1228737, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37601128

RESUMO

Background: Allergic rhinitis is a chronic and refractory disease that can be affected by a variety of factors. Studies have shown an association between cesarean section and the risk of pediatric allergic rhinitis. Methods: The PubMed, Springer, Embase, Cochrane Library, and Web of Science databases were searched to retrieve all studies published from January 2000 to November 2022, focusing on the relationship between cesarean section and the risk of pediatric allergic rhinitis. A meta-analysis was conducted to find a correlation between cesarean section and the risk of pediatric allergic rhinitis. A subgroup analysis was performed, considering the region and family history of allergy, after adjusting for confounding factors. Pooled odds ratios (ORs) were calculated, publication bias was assessed using a funnel plot, and heterogeneity between study-specific relative risks was taken into account. Results: The results showed that cesarean section was significantly associated with an increased risk of pediatric allergic rhinitis (OR: 1.27, 95% CI: 1.20-1.35). Subgroup analysis stratified by region indicated that cesarean section increased the risk of pediatric allergic rhinitis, with the highest increase in South America (OR: 1.67, 95% CI: 1.10-2.52) and the lowest in Europe (OR: 1.13, 95% CI: 1.02-1.25). The results of the subgroup analysis stratified by family history of allergy indicate that family history of allergy was not associated with the risk of pediatric allergic rhinitis. Conclusion: An association exists between cesarean section as the mode of delivery and the increased risk of pediatric allergic rhinitis, and cesarean section is a risk factor for allergic rhinitis.

16.
J Am Chem Soc ; 145(36): 19877-19884, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37584527

RESUMO

Metal-isolated clusters (MICs) physically confined on photoactive materials are of great interest in the field of photosynthesis of hydrogen peroxide (H2O2). Despite recent important endeavors, weak confinement of MICs in the reported photocatalytic systems leads to their low catalytic activity and stability. Herein, we report a new strategy of fluorinated covalent organic frameworks (COFs) to strongly confine Pd ICs for greatly boosting the photocatalytic activity and stability of H2O2 photosynthesis. Both experimental and theoretical results reveal that strong electronegative fluorine can increase the metal-support interaction and optimize the d-band center of Pd ICs, thus significantly enhancing the stability and activity of photocatalytic H2O2. An optimal TAPT-TFPA COFs@Pd ICs photocatalyst delivers a stable H2O2 yield rate of 2143 µmol h-1 g-1. Most importantly, the as-made TAPT-TFPA COFs@Pd ICs exhibit high catalytic stability over 100 h, which is the best among the reported materials.

17.
Small Methods ; 7(10): e2300518, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37401189

RESUMO

Two-dimensional transition metal carbide/nitrides (MXenes) have recently received extensive attention due to their diverse material types and versatile structures, large-scale production, and excellent properties. MXene sheets possess abundant hydrophilic functional groups on their surface, which enable them to be assembled into macroscopic fibers or compounded with other functional materials to produce composite fibers. This review aims to provide a comprehensive analysis of MXene fibers in terms of their fabrication, structure, properties, and recent applications as flexible and wearable electronics. The review will discuss the principles of different methods used to synthesize MXene fibers and analyze the characteristics of the as-synthesized fibers, with a particular focus on the wet spinning method. The fundamental relationships between the microstructure of MXene fibers and their resulting mechanical and electrical properties will be explored. Furthermore, the review will elaborate on the progress made in MXene-based fibers in the rapidly growing field of wearable electronics applications, provide insights into future development of MXene fiber materials and propose solutions to the challenges facing practical applications.

18.
Molecules ; 28(13)2023 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-37446549

RESUMO

Pynegabine, an antiepileptic drug candidate in phase I clinical trials, is a structural analog of the marketed drug retigabine with improved chemical stability, strong efficacy, and a better safety margin. The reported shortest synthetic route for pynegabine contains six steps and involves the manipulation of highly toxic methyl chloroformate and dangerous hydrogen gas. To improve the feasibility of drug production, we developed a concise, three-step process using unconventional methoxycarbonylation and highly efficient Buchwald-Hartwig cross coupling. The new synthetic route generated pynegabine at the decagram scale without column chromatographic purification and avoided the dangerous manipulation of hazardous reagents.


Assuntos
Anticonvulsivantes , Hidrogênio
19.
Proc Natl Acad Sci U S A ; 120(21): e2220315120, 2023 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-37186847

RESUMO

The unsatisfactory catalytic activity of nanozymes owing to their inefficient electron transfer (ET) is the major challenge in biomimetic catalysis-related biomedical applications. Inspired by the photoelectron transfers in natural photoenzymes, we herein report a photonanozyme of single-atom Ru anchored on metal-organic frameworks (UiO-67-Ru) for achieving photoenhanced peroxidase (POD)-like activity. We demonstrate that the atomically dispersed Ru sites can realize high photoelectric conversion efficiency, superior POD-like activity (7.0-fold photoactivity enhancement relative to that of UiO-67), and good catalytic specificity. Both in situ experiments and theoretical calculations reveal that photoelectrons follow the cofactor-mediated ET process of enzymes to promote the production of active intermediates and the release of products, demonstrating more favorable thermodynamics and kinetics in H2O2 reduction. Taking advantage of the unique interaction of the Zr-O-P bond, we establish a UiO-67-Ru-based immunoassay platform for the photoenhanced detection of organophosphorus pesticides.


Assuntos
Peróxido de Hidrogênio , Praguicidas , Biomimética , Compostos Organofosforados , Oxirredução , Catálise
20.
ACS Nano ; 17(9): 8355-8366, 2023 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-37012260

RESUMO

Electronic gloves (e-gloves), with their multifunctional sensing capability, hold a promising application in robotic skin and human-machine interfaces, endowing robots with a human sense of touch. Despite the progress in developing e-gloves by exploiting flexible or stretchable sensors, existing models have inherent rigidity in their sensing area, limiting their stretchability and sensing performance. Herein, we present an all-directional strain-insensitive stretchable e-glove that successfully extends sensing functionality such as pressure, temperature, humidity, and ECG with minimal crosstalk. A scalable and facile method is successfully demonstrated by combining low-cost CO2 laser engraving and electrospinning technology to fabricate multimodal e-glove sensors with a vertical architecture. In comparison to other smart gloves, the proposed e-glove features a ripple-like meandering sensing area and interconnections that are designed to stretch in response to the applied deformation, without affecting the performance of the sensors offering full mechanical stretchability. Furthermore, CNT-coated laser-engraved graphene (CNT/LEG) is used as an active sensing material in which the cross-linking network of the CNT in the LEG minimizes the stress effect and maximizes the sensitivity of the sensors. The fabricated e-glove can detect hot/cold, moisture, and pain simultaneously and precisely, while also allowing for remote transmission of sensory data to the user.


Assuntos
Procedimentos Cirúrgicos Robóticos , Robótica , Humanos , Pele , Tato
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