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2.
Nat Hum Behav ; 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38987357

RESUMO

Recent expansion of proteomic coverage opens unparalleled avenues to unveil new biomarkers of Alzheimer's disease (AD). Among 6,361 cerebrospinal fluid (CSF) proteins analysed from the ADNI database, YWHAG performed best in diagnosing both biologically (AUC = 0.969) and clinically (AUC = 0.857) defined AD. Four- (YWHAG, SMOC1, PIGR and TMOD2) and five- (ACHE, YWHAG, PCSK1, MMP10 and IRF1) protein panels greatly improved the accuracy to 0.987 and 0.975, respectively. Their superior performance was validated in an independent external cohort and in discriminating autopsy-confirmed AD versus non-AD, rivalling even canonical CSF ATN biomarkers. Moreover, they effectively predicted the clinical progression to AD dementia and were strongly associated with AD core biomarkers and cognitive decline. Synaptic, neurogenic and infectious pathways were enriched in distinct AD stages. Mendelian randomization did not support the significant genetic link between CSF proteins and AD. Our findings revealed promising high-performance biomarkers for AD diagnosis and prediction, with implications for clinical trials targeting different pathomechanisms.

3.
Clin Transl Oncol ; 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38965192

RESUMO

BACKGROUND: To develop and validate a serum protein nomogram for colorectal cancer (CRC) screening. METHODS: The serum protein characteristics were extracted from an independent sample containing 30 colorectal cancer and 12 polyp tissues along with their paired samples, and different serum protein expression profiles were validated using RNA microarrays. The prediction model was developed in a training cohort that included 1345 patients clinicopathologically confirmed CRC and 518 normal participants, and data were gathered from November 2011 to January 2017. The lasso logistic regression model was employed for features selection and serum nomogram building. An internal validation cohort containing 576 CRC patients and 222 normal participants was assessed. RESULTS: Serum signatures containing 27 secreted proteins were significantly differentially expressed in polyps and CRC compared to paired normal tissue, and REG family proteins were selected as potential predictors. The C-index of the nomogram1 (based on Lasso logistic regression model) which contains REG1A, REG3A, CEA and age was 0.913 (95% CI, 0.899 to 0.928) and was well calibrated. Addition of CA199 to the nomogram failed to show incremental prognostic value, as shown in nomogram2 (based on logistic regression model). Application of the nomogram1 in the independent validation cohort had similar discrimination (C-index, 0.912 [95% CI, 0.890 to 0.934]) and good calibration. The decision curve (DCA) and clinical impact curve (ICI) analysis demonstrated that nomogram1 was clinically useful. CONCLUSIONS: This study presents a serum nomogram that included REG1A, REG3A, CEA and age, which can be convenient for screening of colorectal cancer.

4.
Cureus ; 16(5): e60372, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38883073

RESUMO

Erythroderma, also known as exfoliative dermatitis, is a rarely reported atypical cutaneous manifestation of adult-onset Still's disease (AOSD). We present the case of erythroderma in association with AOSD that was steroid dependent and responded to tocilizumab therapy. Skin rash, pruritis, and related laboratory findings were significantly improved upon the addition of tocilizumab, while prednisolone was successfully tapered to an ever-lowest maintenance level. To our knowledge, this is the first to report the sole therapeutic effect of tocilizumab in erythroderma related to AOSD.

5.
Science ; 384(6701): 1254-1259, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38870285

RESUMO

Low-dimensional water transport can be drastically enhanced under atomic-scale confinement. However, its microscopic origin is still under debate. In this work, we directly imaged the atomic structure and transport of two-dimensional water islands on graphene and hexagonal boron nitride surfaces using qPlus-based atomic force microscopy. The lattice of the water island was incommensurate with the graphene surface but commensurate with the boron nitride surface owing to different surface electrostatics. The area-normalized static friction on the graphene diminished as the island area was increased by a power of ~-0.58, suggesting superlubricity behavior. By contrast, the friction on the boron nitride appeared insensitive to the area. Molecular dynamic simulations further showed that the friction coefficient of the water islands on the graphene could reduce to <0.01.

6.
J Affect Disord ; 360: 336-344, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38824965

RESUMO

BACKGROUND: The absence of clinically-validated biomarkers or objective protocols hinders effective major depressive disorder (MDD) diagnosis. Compared to healthy control (HC), MDD exhibits anomalies in plasma protein levels and neuroimaging presentations. Despite extensive machine learning studies in psychiatric diagnosis, a reliable tool integrating multi-modality data is still lacking. METHODS: In this study, blood samples from 100 MDD and 100 HC were analyzed, along with MRI images from 46 MDD and 49 HC. Here, we devised a novel algorithm, integrating graph neural networks and attention modules, for MDD diagnosis based on inflammatory cytokines, neurotrophic factors, and Orexin A levels in the blood samples. Model performance was assessed via accuracy and F1 value in 3-fold cross-validation, comparing with 9 traditional algorithms. We then applied our algorithm to a dataset containing both the aforementioned protein quantifications and neuroimages, evaluating if integrating neuroimages into the model improves performance. RESULTS: Compared to HC, MDD showed significant alterations in plasma protein levels and gray matter volume revealed by MRI. Our new algorithm exhibited superior performance, achieving an F1 value and accuracy of 0.9436 and 94.08 %, respectively. Integration of neuroimaging data enhanced our novel algorithm's performance, resulting in an improved F1 value and accuracy, reaching 0.9543 and 95.06 %. LIMITATIONS: This single-center study with a small sample size requires future evaluations on a larger test set for improved reliability. CONCLUSIONS: In comparison to traditional machine learning models, our newly developed MDD diagnostic model exhibited superior performance and showed promising potential for inclusion in routine clinical diagnosis for MDD.


Assuntos
Biomarcadores , Transtorno Depressivo Maior , Imageamento por Ressonância Magnética , Redes Neurais de Computação , Neuroimagem , Humanos , Transtorno Depressivo Maior/sangue , Transtorno Depressivo Maior/diagnóstico por imagem , Biomarcadores/sangue , Imageamento por Ressonância Magnética/métodos , Adulto , Feminino , Masculino , Neuroimagem/métodos , Pessoa de Meia-Idade , Algoritmos , Orexinas/sangue , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Citocinas/sangue , Aprendizado de Máquina , Atenção , Estudos de Casos e Controles
7.
Endocrine ; 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38834859

RESUMO

PURPOSE: There is still controversy in different guidelines regarding the necessity of routine preoperative calcitonin (Ctn) testing in medullary thyroid cancer (MTC). The level of preoperative Ctn may influence the extent of surgery. METHODS: This retrospective multicenter cohort study involved 149 MTC patients from 6 centers between 2013 to 2023. Clinical characteristics, surgical procedure and clinical outcomes were compared between Ctn-screened and Non-screened group. Kaplan-Meier method was used to estimate recurrence-free survival (RFS) and overall survival (OS). RESULTS: In total, 127 MTC patients with preoperative Ctn screening and 22 MTC patients without screening were analyzed. MTC patients with preoperative Ctn screening underwent more radical surgical procedures including total thyroidectomy and lymph node dissection, compared to those without screening (84.3% vs. 68.2% and 91.3% vs. 72.7%, respectively). The rate of recurrence and death were lower in the Ctn-screened group (16.1% vs. 36.4%, 0.8% vs. 18.2%, respectively). The survival curve showed a significantly better overall survival in Ctn-screened group than Non-screened group (HR:17.932, 95% CI 1.888-170.294, p-value = 0.001), while no significant difference was observed of RFS between two groups (HR:1.6, 95% CI 0.645-3.966, p-value = 0.307). CONCLUSION: Preoperative Ctn screening can prompt surgeons choosing more radical initial surgical treatment for MTC patients, potentially leading to better long-term outcomes. Further evaluation of the cost-effectiveness of routine Ctn screening in thyroid nodule patients is warranted.

8.
Nat Commun ; 15(1): 4849, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38844505

RESUMO

Porphyry-type molybdenum deposits, many of which are in China, supply most of the World's molybdenum. Of particular importance are the molybdenum deposits located in the Qinling-Dabie region that are responsible for more than half of China's molybdenum production. A feature that distinguishes this suite of deposits from the better-known Climax and Endako sub-types of porphyry molybdenum deposits is their formation from CO2-rich magmatic-hydrothermal fluids. The role of CO2, if any, in the transport of molybdenum by these fluids, however, is poorly understood. We conducted experiments on the partitioning of molybdenum between H2O-CO2, H2O-NaCl, and H2O-NaCl-CO2 fluids and a felsic melt at 850 °C and 100 and 200 MPa. Here we show that the exsolution of separate (immiscible) brine and vapor leads to the very high brine DMo values needed for efficient extraction of Mo from the magmas forming Dabie-type porphyry molybdenum deposits.

9.
Pestic Biochem Physiol ; 202: 105933, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38879325

RESUMO

Citrus sour rot is a common postharvest citrus disease caused by Geotrichum citri-aurantiiti, which has led to enormous economic losses, particularly during rainy seasons. In this study, we aimed to clarify the impact of berberine hydrochloride (BH), the hydrochloride form of an isoquinoline alkaloid, on the control efficiency of citrus sour rot and its antifungal mode against G. citri-aurantii. Results demonstrated that BH markedly impede the propagation of G. citri-aurantii by delaying the spores development from dormant stage into swollen and germinating stages, with the MIC and MFC value of 0.08 and 0.16 g L-1, respectively. When the artificially inoculated citrus fruit in control group were totally rotted, the disease incidence of BH-treated groups decreased by 35.00%-73.30%, which effectively delayed the disease progression and almost did not negatively affect fruit quality. SEM observation, CFW and PI staining images revealed that BH caused significant damage to both the cell membrane and cell wall of G. citri-aurantii spores, whereas only the cell membrane of the mycelium was affected. The impact of cell wall was related to the block of chitin and ß-1,3-glucan synthesis. Transcriptome results and further verification proved that 0.5 × MIC BH treatment affected the glycolysis pathway and TCA cycle mainly by inhibiting the production of acetyl-CoA and pyruvate. Subsequently, the activities of key enzymes declined, resulting in a further decrease in ATP levels, ultimately inhibiting the germination of spores. In conlusion, BH delays citrus sour rot mainly by disrupting carbohydrate and energy metabolism of G. citri-aurantii spores.


Assuntos
Berberina , Citrus , Metabolismo Energético , Geotrichum , Doenças das Plantas , Esporos Fúngicos , Citrus/microbiologia , Geotrichum/efeitos dos fármacos , Geotrichum/metabolismo , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Berberina/farmacologia , Metabolismo Energético/efeitos dos fármacos , Esporos Fúngicos/efeitos dos fármacos , Metabolismo dos Carboidratos/efeitos dos fármacos , Fungicidas Industriais/farmacologia
11.
Materials (Basel) ; 17(12)2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38930308

RESUMO

The two-step thermal stress calculation method (TTSCM) is commonly used to predict the cracking temperature of asphalt mixture. The aim of this study is to improve TTSCM's mathematical model so as to enhance its prediction accuracy. First, this study evaluated the errors of predicted cracking temperatures of original TTSCM for AC-16 and AC-25 asphalt mixtures by thermal stress-restrained specimen test (TSRST). Then, an improved method called the extended creep compliance test (ECCT) was developed to modify the TTSCM. The test results show that the cracking predictions of the original TTSCM are not always accurate. Particularly for AC-16 asphalt mixture, the predicted cracking temperature is 2.9 °C (-10.6%) higher than the measured value by the TSRST. The ECCT method has been proven to be an effective way to enhance the prediction accuracy of the TTSCM. The predicted cracking temperatures modified by the ECCT method for both asphalt mixtures are relatively accurate, having an error within ±2%. The ECCT method changed the calculated thermal stress values at different temperatures of the TTSCM; however, they still conformed to a basic changing trend with respect to the initial temperature and cooling rate. Finally, a recommendation regarding the ECCT method was presented.

12.
Adv Mater ; : e2404833, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38847439

RESUMO

The development of new near-infrared-responsive photocatalysts is a fascinating and challenging approach to acquire high photocatalytic hydrogen evolution (PHE) performance. Herein, near-infrared-responsive black CuVP2S6 and CuCrP2S6 flakes, as well as CuInP2S6 flakes, are designed and constructed for PHE. Atom-resolved scanning transmission electron microscopy images and X-ray absorption fine structure evidence the formation of ultrathin single-crystalline sheet-like structure of CuVP2S6 and CuCrP2S6. The synthetic CuVP2S6 and CuCrP2S6, with a narrow bandgap of ≈1.0 eV, shows the high light-absorption edge exceeding 1100 nm. Moreover, through the femtosecond-resolved transient absorption spectroscopy, CuCrP2S6 displays the efficient charge transfer and long charge lifetime (18318.1 ps), which is nearly 3 and 29 times longer than that of CuVP2S6 and CuInP2S6, respectively. In addition, CuCrP2S6, with the appropriate d-band and p-band, is thermodynamically favorable for the H+ adsorption and H2 desorption by contrast with CuVP2S6 and CuInP2S6. As a result, CuCrP2S6 exhibits high PHE rates of 9.12 and 0.66 mmol h-1 g-1 under simulated sunlight and near-infrared light irradiation, respectively, far exceeding other layered metal phospho-sulfides. This work offers a distinctive perspective for the development of new near-infrared-responsive photocatalysts.

14.
Ann Surg Oncol ; 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38824192

RESUMO

BACKGROUND: This study was designed to develop an innovative classification and guidance system for renal hilar tumors and to assess the safety and effectiveness of robot-assisted partial nephrectomy (RAPN) for managing such tumors. METHODS: A total of 179 patients undergoing RAPN for renal hilar tumors were retrospectively reviewed. A novel classification system with surgical techniques was introduced and the perioperative features, tumor characteristics, and the efficacy and safety of RAPN were compared within subgroups. RESULTS: We classified the tumors according to our novel system as follows: 131 Type I, 35 Type II, and 13 Type III. However, Type III had higher median R.E.N.A.L., PADUA, and ROADS scores compared with the others (all p < 0.001), indicating increased operative complexity and higher estimated blood loss [180.00 (115.00-215.00) ml]. Operative outcomes revealed significant disparities between Type III and the others, with longer operative times [165.00 (145.00-200.50) min], warm ischemia times [24.00 (21.50-30.50) min], tumor resection times [13.00 (12.00-15.50) min], and incision closure times [22.00 (20.00-23.50) min] (all p < 0.005). Postoperative outcomes also showed significant differences, with longer durations of drain removal (77.08 ± 18.16 h) and hospitalization for Type III [5.00 (5.00-6.00) d] (all p < 0.05). Additionally, Type I had a larger tumor diameter than the others (p = 0.009) and pT stage differed significantly between the subtypes (p = 0.020). CONCLUSIONS: The novel renal hilar tumor classification system is capable of differentiating the surgical difficulty of RAPN and further offers personalized surgical steps tailored to each specific classification. It provides a meaningful tool for clinical practice.

15.
Dig Dis Sci ; 69(7): 2540-2547, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38700630

RESUMO

BACKGROUND: Bismuth-containing quadruple therapy is the first-line treatment for eradicating Helicobacter pylori (H. pylori). The optimal duration for H. pylori eradication using bismuth-containing quadruple therapy remains controversial. Therefore, we aimed to compare the clinical effects of the 10- and 14-day bismuth-containing quadruple treatment regimen to eradicate H. pylori. METHODS: Treatment-naïve patients with H. pylori infection (n = 1300) were enrolled in this multicenter randomized controlled study across five hospitals in China. They were randomized into 10- or 14-day treatment groups to receive bismuth-containing quadruple therapy as follows: vonoprazan 20 mg twice daily; bismuth 220 mg twice daily; amoxicillin 1000 mg twice daily; and either clarithromycin 500 mg twice daily or tetracycline 500 mg four times daily. At least 6 weeks after treatment, we performed a 13C-urea breath test to evaluate H. pylori eradication. RESULTS: The per-protocol eradication rates were 93.22% (564/605) and 93.74% (569/607) (p < 0.001) and the intention-to-treat eradication rates were 88.62% (576/650) and 89.38% (581/650) (p = 0.007) for the 10- and 14-day regimens, respectively. Incidence of adverse effects was lower in patients who received 10- vs. 14 days of treatment (22.59% vs. 28.50%, p = 0.016). We observed no significant differences in the compliance to treatment or the discontinuation of therapy because of severe adverse effects between the groups. CONCLUSION: Compared with the 14-day bismuth-containing quadruple regimens, the 10-day regimen demonstrated a non-inferior efficacy and lower incidence of adverse effects. Therefore, the 10-day regimen is safe and tolerated and could be recommended for H. pylori eradication (NCT05049902).


Assuntos
Amoxicilina , Antibacterianos , Bismuto , Claritromicina , Esquema de Medicação , Quimioterapia Combinada , Infecções por Helicobacter , Helicobacter pylori , Sulfonamidas , Tetraciclina , Humanos , Infecções por Helicobacter/tratamento farmacológico , Infecções por Helicobacter/diagnóstico , Helicobacter pylori/efeitos dos fármacos , Pessoa de Meia-Idade , Masculino , Feminino , Tetraciclina/administração & dosagem , Tetraciclina/uso terapêutico , Antibacterianos/administração & dosagem , Antibacterianos/efeitos adversos , Bismuto/administração & dosagem , Bismuto/uso terapêutico , Bismuto/efeitos adversos , Adulto , Claritromicina/administração & dosagem , Amoxicilina/administração & dosagem , Sulfonamidas/administração & dosagem , Pirróis/administração & dosagem , Pirróis/efeitos adversos , Inibidores da Bomba de Prótons/administração & dosagem , Inibidores da Bomba de Prótons/efeitos adversos , Testes Respiratórios , Resultado do Tratamento , Idoso , China
16.
Aging (Albany NY) ; 16(9): 7799-7817, 2024 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-38696317

RESUMO

Non-small cell lung cancer (NSCLC) is the most common histopathological type, and it is purposeful for screening potential prognostic biomarkers for NSCLC. This study aims to identify the lncRNAs and mRNAs related to survival of non-small cell lung cancer (NSCLC). The expression profile data of lung adenocarcinoma and lung squamous cell carcinoma were downloaded in The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) dataset. A total of eight survival related long non-coding RNAs (lncRNAs) and 262 survival related mRNAs were filtered. By gene set enrichment analysis, 17 significantly correlated Gene Ontology signal pathways and 14 Kyoto Encyclopedia of Genes and Genomes signal pathways were screened. Based on the clinical survival and prognosis information of the samples, we screened eight lncRNAs and 193 mRNAs by single factor Cox regression analysis. Further single and multifactor Cox regression analysis were performed, 30 independent prognostication-related mRNAs were obtained. The PPI network was further constructed. We then performed the machine learning algorithms (Least absolute shrinkage and selection operator, Recursive feature elimination, and Random forest) to screen the optimized DEGs combination, and a total of 17 overlapping mRNAs were obtained. Based on the 17 characteristic mRNAs obtained, we firstly built a Nomogram prediction model, and the ROC values of training set and testing set were 0.835 and 0.767, respectively. By overlapping the 17 characteristic mRNAs and PPI network hub genes, three genes were obtained: CDC6, CEP55, TYMS, which were considered as key factors associated with survival of NSCLC. The in vitro experiments were performed to examine the effect of CDC6, CEP55, and TYMS on NSCLC cells. Finally, the lncRNAs-mRNAs networks were constructed.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Biologia Computacional , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares , Aprendizado de Máquina , RNA Longo não Codificante , RNA Mensageiro , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/patologia , Humanos , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Biologia Computacional/métodos , Prognóstico , Biomarcadores Tumorais/genética , Perfilação da Expressão Gênica , Redes Reguladoras de Genes , Nomogramas
17.
Kaohsiung J Med Sci ; 40(7): 650-659, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38757734

RESUMO

Colorectal cancer (CRC) is notable for its high mortality and high metastatic characteristics. The shear force generated by bloodstream provides mechanical signals regulating multiple responses of cells, including metastatic cancer cells, dispersing in blood vessels. We, therefore, studied the effect of shear flow on circulating CRC cells in the present study. The CRC cell line SW620 was subjected to shear flow of 12.5 dynes/cm2 for 1 and 2 h separately. Resulting elevated caspase-9 and -3 indicated that shear flow initiated the apoptosis of SW620. Enlarged cell size associated with a higher level of cyclin D1 was coincident with the flow cytometric results indicating that the cell cycle was arrested at the G1 phase. An elevated phosphor-eNOSS1177 increased the production of nitric oxide and led to reactive oxygen species-mediated oxidative stress. Shear flow also regulated epithelial-mesenchymal transition (EMT) by increasing E-cadherin and ZO-1 while decreasing Snail and Twist1. The migration and invasion of sheared SW620 were also substantially decreased. Further investigations showed that mitochondrial membrane potential was significantly decreased, whereas mitochondrial mass and ATP production were not changed. In addition to the shear flow of 12.5 dynes/cm2, the expressions of EMT were compared at lower (6.25 dynes/cm2) and at higher (25 dynes/cm2) shear flow. The results showed that lower shear flow increased mesenchymal characteristics and higher shear flow increased epithelial characteristics. Shear flow reduces the malignancy of CRC in their metastatic dispersal that opens up new ways to improve cancer therapies by applying a mechanical shear flow device.


Assuntos
Apoptose , Movimento Celular , Neoplasias Colorretais , Transição Epitelial-Mesenquimal , Espécies Reativas de Oxigênio , Humanos , Neoplasias Colorretais/patologia , Neoplasias Colorretais/metabolismo , Linhagem Celular Tumoral , Espécies Reativas de Oxigênio/metabolismo , Estresse Mecânico , Potencial da Membrana Mitocondrial , Ciclina D1/metabolismo , Estresse Oxidativo , Caderinas/metabolismo , Óxido Nítrico/metabolismo , Caspase 9/metabolismo , Caspase 3/metabolismo , Proteína da Zônula de Oclusão-1/metabolismo , Proteína 1 Relacionada a Twist/metabolismo
18.
Adv Mater ; : e2404851, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38742925

RESUMO

Photocatalytic synthesis of hydrogen peroxide (H2O2) from O2 and H2O under near-infrared light is a sustainable renewable energy production strategy, but challenging reaction. The bottleneck of this reaction lies in the regulation of O2 reduction path by photocatalyst. Herein, the center of the one-step two-electron reduction (OSR) pathway of O2 for H2O2 evolution via the formation of the hydroxyl-bonded Co single-atom sites on boroncarbonitride surface (BCN-OH2/Co1) is constructed. The experimental and theoretical prediction results confirm that the hydroxyl group on the surface and the electronic band structure of BCN-OH2/Co1 are the key factor in regulating the O2 reduction pathway. In addition, the hydroxyl-bonded Co single-atom sites can further enrich O2 molecules with more electrons, which can avoid the one-electron reduction of O2 to •O2 -, thus promoting the direct two-electron activation hydrogenation of O2. Consequently, BCN-OH2/Co1 exhibits a high H2O2 evolution apparent quantum efficiency of 0.8% at 850 nm, better than most of the previously reported photocatalysts. This study reveals an important reaction pathway for the generation of H2O2, emphasizing that precise control of the active site structure of the photocatalyst is essential for achieving efficient conversion of solar-to-chemical.

19.
Macromol Rapid Commun ; : e2400163, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38690806

RESUMO

Synthesis of monomer-recyclable polyesters solely from CO2 and bulk olefins holds great potential in significantly reducing CO2 emissions and addressing the issue of plastic pollution. Due to the kinetic disadvantage of direct copolymerization of CO2 and bulk olefins compared to homopolymerization of bulk olefins, considerable research attention has been devoted to synthesis of polyester via the ring-opening polymerization (ROP) of a six-membered disubstituted lactone intermediate, 1,2-ethylidene-6-vinyl-tetrahydro-2H-pyran-2-one (𝜹-L), obtained from telomerization of CO2 and 1,3-butadiene. However, the conjugate olefin on the six-membered ring of 𝜹-L leads to serious Michael addition side reactions. Thus, the selective ROP of 𝜹-L, which can precisely control the repeating unit for the production of polyesters potentially amenable to efficient monomer recycling, remains an unresolved challenge. Herein, the first example of selective ROP of 𝜹-L is reported using a combination of organobase and N,N'-Bis[3,5-bis(trifluoromethyl)phenyl]urea as the catalytic system. Systematic modifications of the substituent of the urea show that the presence of electron-deficient 3,5-bis(trifluoromethyl)-phenyl groups is the key to the extraordinary selectivity of ring opening over Michael addition. Efficient monomer recovery of oligo(𝜹-L) is also achieved under mild catalytic conditions.

20.
J Org Chem ; 89(10): 7163-7168, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38721654

RESUMO

A [3 + 2] cycloaddition of C,N-cyclic azomethine imine with in situ-generated CF3CN for the construction of 2-(trifluoromethyl)-[1,2,4]triazolo[5,1-a]isoquinoline is reported. Remarkably, this process shows a broad substrate scope with excellent functional group tolerance, which is scalable and enables a practical route to a library of 2-(trifluoromethyl)-[1,2,4]triazolo[5,1-a]isoquinoline derivatives in moderate to good yields.

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