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1.
J Am Chem Soc ; 146(30): 20649-20659, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39018421

RESUMO

When catalytic reactions are interfered with by radiation sources, thorium clusters are promising as potential catalysts due to their superior radiation resistance. However, there is currently very little research on the design synthesis and catalytic application of radiation-stable thorium clusters. In this work, we have elaborately engineered and fabricated three high-nuclear thorium cluster catalysts denoted as Th12L3-MA12, Th12L3-MA6-BF6, and Th12L3-Fcc12, which did not undergo any significant alterations in their molecular structures and compositions after irradiation with 690 kGy γ-rays. We systematically investigated the photocatalytic/thermocatalytic properties of these radiation-resistant thorium clusters for the first time and found that γ-rays could not alter their catalytic activities. In addition, it was found that ligand engineering could modulate the catalytic activity of thorium clusters, thus expanding the range of catalytic applications of thorium clusters, including reduction reactions (nitroarene reduction) and some oxidation reactions (N-heterocyclic oxidative dehydrogenation and diphenylmethane oxidation). Meanwhile, all of these organic transformation reactions achieved a >80% conversion and nearly 100% product selectivity. Radiation experiments combined with DFT calculations showed that the synergistic catalysis of thorium-oxo core and ligands led to the generation of specific active species (H+, O2•-, or tBuO/tBuOO•) and activation of substrate molecules, thus achieving superior catalytic performance. This work is not only the first to develop radiation-resistant thorium cluster catalysts to perform efficient redox reactions but also provides design ideas for the construction of high-nuclearity thorium clusters under mild conditions.

3.
Food Res Int ; 187: 114428, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38763678

RESUMO

In this study, blackberry polysaccharide-selenium nanoparticles (BBP-24-3Se) were first prepared via Na2SeO3/Vc redox reaction, followed by coating with red blood cell membrane (RBC) to form core-shell structure polysaccharide-selenium nanoparticles (RBC@BBP-24-3Se). The particle size of BBP-24-3Se (167.1 nm) was increased to 239.8 nm (RBC@BBP-24-3Se) with an obvious core-shell structure after coating with RBC. FT-IR and XPS results indicated that the interaction between BBP-24-3 and SeNPs formed a new C-O···Se bond with valence state of Se0. Bioassays indicated that RBC coating markedly enhanced both the biocompatibility and bioabsorbability of RBC@BBP-24-3Se, and the absorption rate of RBC@BBP-24-3Se in HepG2 cells was 4.99 times higher than that of BBP-24-3Se at a concentration of 10 µg/mL. Compared with BBP-24-3Se, RBC@BBP-24-3Se possessed significantly heightened protective efficacy against oxidative damage and better regulation of glucose/lipid metabolism disorder induced by palmitic acid in HepG2 cells. Mechanistic studies demonstrated that RBC@BBP-24-3Se could effectively improve PI3K/AKT signaling pathway to promote glucose metabolism, inhibit the expression of lipid synthesis genes and up-regulate the expression of lipid-decomposing genes through AMPK signaling pathway to improve lipid metabolism. These results provided a theoretical basis for developing a new type of selenium supplement for the treatment of insulin resistance.


Assuntos
Glucose , Metabolismo dos Lipídeos , Nanopartículas , Polissacarídeos , Rubus , Selênio , Humanos , Selênio/química , Células Hep G2 , Polissacarídeos/farmacologia , Polissacarídeos/química , Metabolismo dos Lipídeos/efeitos dos fármacos , Glucose/metabolismo , Nanopartículas/química , Rubus/química , Tamanho da Partícula , Estresse Oxidativo/efeitos dos fármacos , Antioxidantes/farmacologia , Transdução de Sinais/efeitos dos fármacos
5.
Sci Bull (Beijing) ; 69(10): 1418-1426, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38485624

RESUMO

The Zr(IV) ions are easily hydrolyzed to form oxides, which severely limits the discovery of new structures and applications of Zr-based compounds. In this work, three ferrocene (Fc)-functionalized Zr-oxo clusters (ZrOCs), Zr9Fc6, Zr10Fc6 and Zr12Fc8 were synthesized through inhibiting the hydrolysis of Zr(IV) ions, which show increased nuclearity and regular structural variation. More importantly, these Fc-functionalized ZrOCs were used as heterogeneous catalysts for the transfer hydrogenation of levulinic acid (LA) and phenol oxidation reactions for the first time, and displayed outstanding catalytic activity. In particular, Zr12Fc8 with the largest number of Zr active sites and Fc groups can achieve > 95% yield for LA-to-γ-valerolactone within 4 h (130 °C) and > 98% yield for 2,3,6-trimethylphenol-to-2,3,5-trimethyl-p-benzoquinone within 30 min (80 °C), showing the best catalytic performance. Catalytic characterization combined with theory calculations reveal that in the Fc-functionalized ZrOCs, the Zr active sites could serve as substrate adsorption sites, while the Fc groups could act as hydrogen transfer reagent or Fenton reagent, and thus achieve effectively intramolecular metal-ligand synergistic catalysis. This work develops functionalized ZrOCs as catalysts for thermal-triggered redox reactions.

6.
Nat Biomed Eng ; 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38491329

RESUMO

Dental calculi can cause gingival bleeding and periodontitis, yet the mechanism underlying the formation of such mineral build-ups, and in particular the role of the local microenvironment, are unclear. Here we show that the formation of dental calculi involves bacteria in local mature biofilms converting the DNA in neutrophil extracellular traps (NETs) from being degradable by the enzyme DNase I to being degradation resistant, promoting the nucleation and growth of apatite. DNase I inhibited NET-induced mineralization in vitro and ex vivo, yet plasma DNases were ineffective at inhibiting ectopic mineralization in the oral cavity in rodents. The topical application of the DNA-intercalating agent chloroquine in rodents fed with a dental calculogenic diet reverted NET DNA to its degradable form, inhibiting the formation of calculi. Our findings may motivate therapeutic strategies for the reduction of the prevalence of the deposition of bacteria-driven calculi in the oral cavity.

7.
Angew Chem Int Ed Engl ; 63(14): e202318180, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38242848

RESUMO

Although photocatalytic C-H activation has been realized by using heterogeneous catalysts, most of them require high-temperature conditions to provide the energy required for C-H bond breakage. The catalysts with photothermal conversion properties can catalyze this reaction efficiently at room temperature, but so far, these catalysts have been rarely developed. Here, we construct bifunctional catalysts Rh-COF-316 and -318 to combine photosensitive covalent organic frameworks (COFs) and transition-metal catalytic moiety using a post-synthetic approach. The Rh-COF enable the heterogeneous C-H activation reaction by photothermal conversion for the first time, and exhibit excellent yields (up to 98 %) and broad scope of substrates in [4+2] annulation at room temperature, while maintaining the high stability and recyclability. Significantly, this work is the highest yield reported so far in porous materials catalyzing C(sp2)-C(sp2) formation at room temperature. The excellent performances can be attributed to the COF-316, which enhances the photothermal effect (ΔT=50.9 °C), thus accelerating C-H bond activation and the exchange of catalyst with substrates.

8.
World J Surg Oncol ; 22(1): 3, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38166925

RESUMO

OBJECTIVE: To compare the effects of laparoscopic hepatectomy (LH) on the short-term and long-term outcomes in hepatocellular carcinoma (HCC) patients with and without clinically significant portal hypertension (CSPH). METHODS: A systematic literature search of the PubMed, EMBASE, and Cochrane databases was performed for articles published from inception to March 1, 2023. Meta-analysis of surgical and oncological outcomes was performed using a random effects model. Data were summarized as mean difference and risk ratio with 95% confidence intervals. RESULTS: Five cohort studies with a total of 310 HCC patients were included (CSPH 143; Non-CSPH 167). In terms of surgical outcomes, estimated blood loss and the length of hospital stay were significantly lower in the Non-CSPH group than in the CSPH group. There were no significant differences between the two groups regarding other surgical outcomes, including the operative time, ratio of conversion to open surgery, and overall complication rate. In addition, there were also no significant differences between the two groups regarding the oncological outcomes, such as 1-, 3-, and 5-year overall survival. CONCLUSIONS: HCC patients with and without CSPH who underwent LH had comparable surgical and oncological outcomes. LH is a safe and effective treatment for HCC patients with CSPH under the premise of rational screening of patients.


Assuntos
Carcinoma Hepatocelular , Hipertensão Portal , Laparoscopia , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/complicações , Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/complicações , Neoplasias Hepáticas/cirurgia , Hepatectomia/efeitos adversos , Resultado do Tratamento , Hipertensão Portal/complicações , Hipertensão Portal/cirurgia , Laparoscopia/efeitos adversos , Tempo de Internação , Estudos Retrospectivos
9.
Angew Chem Int Ed Engl ; 63(11): e202320036, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38191990

RESUMO

The striking aesthetic appeal of fullerene-like clusters has captured the interest of researchers. Nevertheless, the assembly of fullerene-like polyoxovadanadate (POV) cages remains a significant challenge due to the scarcity of suitable pentagonal motif. Herein, we have successfully synthesized the first fullerene-like all-inorganic POV cage, {(V2 O)V30 Nb12 O102 (H2 O)12 } (V30 Nb12 ), by introducing Nb into the POVs. V30 Nb12 is assembled by 12 heterometallic {(Nb)V5 } pentagons through sharing V centers with Ih symmetry, reminiscent of C60 . To our knowledge, the fullerene-like V30 Nb12 not only represents the highest-nuclearity POV cage but also stands as the first niobovanadate cluster. Notably, V30 Nb12 exhibits excellent solution stability, as confirmed by ESI-MS, FT-IR and UV/Vis spectra. As there is no protection organic ligand on its outer surface, V30 Nb12 can be further modified with Cu-complexes to form a fullerene-like cluster based zigzag chain (Cu-V30 Nb12 ).

10.
Nat Commun ; 15(1): 537, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38225374

RESUMO

In modern industries, the aerobic oxidation of C(sp3)-H bonds to achieve the value-added conversion of hydrocarbons requires high temperatures and pressures, which significantly increases energy consumption and capital investment. The development of a light-driven strategy, even under natural sunlight and ambient air, is therefore of great significance. Here we develop a series of hetero-motif molecular junction photocatalysts containing two bifunctional motifs. With these materials, the reduction of O2 and oxidation of C(sp3)-H bonds can be effectively accomplished, thus realizing efficient aerobic oxidation of C(sp3)-H bonds in e.g., toluene and ethylbenzene. Especially for ethylbenzene oxidation reactions, excellent catalytic capacity (861 mmol g cat-1) is observed. In addition to the direct oxidation of C(sp3)-H bonds, CeBTTD-A can also be applied to other types of aerobic oxidation reactions highlighting their potential for industrial applications.

11.
Adv Mater ; 36(15): e2310061, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38227292

RESUMO

Integrating the advantages of homogeneous and heterogeneous catalysis has proved to be an optimal strategy for developing catalytic systems with high efficiency, selectivity, and recoverability. Supramolecular metal-organic cages (MOCs), assembled by the coordination of metal ions with organic linkers into discrete molecules, have performed solvent processability due to their tunable packing modes, endowing them with the potential to act as homogeneous or heterogeneous catalysts in different solvent systems. Here, the design and synthesis of a series of stable {Cu3} cluster-based tetrahedral MOCs with varied packing structures are reported. These MOCs, as homogeneous catalysts, not only show high catalytic activity and selectivity regardless of substrate size during the CO2 cycloaddition reaction, but also can be easily recovered from the reaction media through separating products and co-catalysts by one-step work-up. This is because that these MOCs have varied solubilities in different solvents due to the tunable packing of MOCs in the solid state. Moreover, the entire catalytic reaction system is very clean, and the purity of cyclic carbonates is as high as 97% without further purification. This work provides a unique strategy for developing novel supramolecular catalysts that can be used for homogeneous catalysis and recycled in a heterogeneous manner.

12.
Surg Endosc ; 38(1): 56-65, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38017157

RESUMO

OBJECTIVE: How different surgical procedures, including the robotic-assisted liver resection (RLR) and laparoscopic liver resection (LLR), can affect the prognosis of patients with liver malignancies is unclear. Thus, in this study, we compared the effects of RLR and LLR on the surgical and oncological outcomes in patients with liver malignancies through propensity score-matched cohort studies. METHODS: The PubMed, Embase, and Cochrane databases were searched using Medical Subject Headings terms and keywords from inception until May 31, 2023. The quality of the included studies was assessed using the Newcastle-Ottawa quality assessment scale. The mean difference with 95% confidence interval (95% CI) was used for analysis of continuous variables; the risk ratio with 95% CI was used for dichotomous variables; and the hazard ratio with 95% CI was used for survival-related variables. Meta-analysis was performed using a random-effects model. RESULTS: Five high-quality cohort studies with 986 patients were included (370 and 616 cases for RLR and LLR, respectively). In terms of surgical outcomes, there were no significant differences in the operation time, conversion rate to open surgery, overall complication rate, major complication rate, and length of hospital stay between the RLR and LLR groups. In terms of oncological outcomes, there were no significant differences in the 5-year overall survival and disease-free survival between the two groups. CONCLUSION: Surgical and oncological outcomes are comparable between RLR and LLR on patients with liver malignancies. Therefore, the benefits of applying RLR in patients with liver malignancies need to be further explored.


Assuntos
Carcinoma Hepatocelular , Laparoscopia , Neoplasias Hepáticas , Procedimentos Cirúrgicos Robóticos , Humanos , Pontuação de Propensão , Hepatectomia/métodos , Laparoscopia/métodos , Tempo de Internação , Estudos Retrospectivos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia
13.
Chinese Journal of Oncology ; (12): 57-65, 2024.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1045840

RESUMO

Objective: This paper provides a brief overview of the epidemiology of colorectal cancer in China and around the world, and discusses how to prevent colorectal cancer to reduce its disease burden. Method: Using the official database of GLOBOCAN 2020, the China Cancer Registry Annual Report compiled by the National Cancer Center, and data from CONCORD-3.Data management was performed by Microsoft Excel 2016 and R 4.2.1 Relevant graphs were generated using the ggplot2 package for result visualization. Result: An estimated 1 931 590 people were diagnosed with colorectal cancer worldwide in 2020 with an age-standardized incidence rate of 19.5 per 100 000. There were about 935 173 deaths caused by colorectal cancer internationally, with an age-standardized mortality rate of 9.0 per 100 000. Overall, colorectal cancer was the fourth most commonly diagnosed cancer and the third leading cause of cancer-related death worldwide in 2020. In China, the age-standardized incidence rate and mortality rate of colorectal cancer was 17.3 per 100 000 and 7.8 per 100 000, respectively. Gender differences in trends were observed, with a decreasing trend in incidence and mortality among females and an increasing trend in incidence and mortality among males. The primary risk factors for colorectal cancer include age, genetic factors, gastrointestinal disorders, dietary habits, and lifestyle et al. Conclusions: Colorectal cancer poses a significant burden globally and in China. The occurrence of colorectal cancer is closely related to physiology, genetics, behavioral habits, lifestyle, and disease factors. To better control the colorectal cancer burden with the lowest cost, specific measures should be taken to reduce exposure to established risk factors. By combining the disease prevention and control strategies of tertiary prevention in China with the characteristic factors of colorectal cancer, the incidence and mortality of colorectal cancer may be effectively controlled.


Assuntos
Feminino , Masculino , Humanos , Prevalência , China/epidemiologia , Bases de Dados Factuais , Sistema de Registros , Neoplasias Colorretais/prevenção & controle
14.
Chinese Journal of Oncology ; (12): 57-65, 2024.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1046163

RESUMO

Objective: This paper provides a brief overview of the epidemiology of colorectal cancer in China and around the world, and discusses how to prevent colorectal cancer to reduce its disease burden. Method: Using the official database of GLOBOCAN 2020, the China Cancer Registry Annual Report compiled by the National Cancer Center, and data from CONCORD-3.Data management was performed by Microsoft Excel 2016 and R 4.2.1 Relevant graphs were generated using the ggplot2 package for result visualization. Result: An estimated 1 931 590 people were diagnosed with colorectal cancer worldwide in 2020 with an age-standardized incidence rate of 19.5 per 100 000. There were about 935 173 deaths caused by colorectal cancer internationally, with an age-standardized mortality rate of 9.0 per 100 000. Overall, colorectal cancer was the fourth most commonly diagnosed cancer and the third leading cause of cancer-related death worldwide in 2020. In China, the age-standardized incidence rate and mortality rate of colorectal cancer was 17.3 per 100 000 and 7.8 per 100 000, respectively. Gender differences in trends were observed, with a decreasing trend in incidence and mortality among females and an increasing trend in incidence and mortality among males. The primary risk factors for colorectal cancer include age, genetic factors, gastrointestinal disorders, dietary habits, and lifestyle et al. Conclusions: Colorectal cancer poses a significant burden globally and in China. The occurrence of colorectal cancer is closely related to physiology, genetics, behavioral habits, lifestyle, and disease factors. To better control the colorectal cancer burden with the lowest cost, specific measures should be taken to reduce exposure to established risk factors. By combining the disease prevention and control strategies of tertiary prevention in China with the characteristic factors of colorectal cancer, the incidence and mortality of colorectal cancer may be effectively controlled.


Assuntos
Feminino , Masculino , Humanos , Prevalência , China/epidemiologia , Bases de Dados Factuais , Sistema de Registros , Neoplasias Colorretais/prevenção & controle
15.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1021371

RESUMO

BACKGROUND:Obesity and its relevant chronic inflammation are important risk factors for inducing type 2 diabetes.This inflammatory response will further involve skeletal muscle,leading to an increase in catabolic and autophagic fluxes in skeletal muscle.Aerobic exercise is the mainstream mode of exercise in the prevention and treatment of type 2 diabetes,and may also has a certain protective effect on skeletal muscle. OBJECTIVE:To explore the effects and regulatory mechanisms of aerobic exercise on glucolipid metabolism,skeletal muscle inflammation and autophagy in type 2 diabetic rats. METHODS:Animal models of type 2 diabetes were established in rats by 8-week high-fat feeding combined with streptozotocin injection,and the experimental rats were then divided into normal control group,normal exercise group,diabetic control group and diabetic exercise group.The exercise group performed 4 weeks of aerobic exercise(16 m/min,60 min/d,5 d/wk).The levels of blood glucose,high-density lipoprotein,low-density lipoprotein and triglyceride in serum were measured by an automated biochemical analyzer.Serum insulin level was determined using enzyme-linked immunosorbent assay and the insulin resistance index and area under the glucose metabolism curve were calculated.The levels of interleukin 6 and tumor necrosis factor α in skeletal muscle were measured by enzyme-linked immunosorbent assay after 4 weeks of aerobic exercise,and the expression levels of forkhead box protein O3(FoxO3),LC3 and p62 in skeletal muscle were measured by western blot assay. RESULTS AND CONCLUSION:The area under the glucose tolerance curve and insulin resistance index both increased significantly in type 2 diabetic rats(P<0.001,P=0.025),and aerobic exercise significantly reduced the area under the glucose tolerance curve and insulin resistance index in the normal exercise group(P<0.001,P=0.038)and diabetic exercise group(P<0.001,P=0.004).Serum high-density lipoprotein significantly decreased(P=0.030),and low-density lipoprotein and triglyceride(P=0.027,P=0.014)levels significantly increased in the diabetic control group compared with the normal control group.Aerobic exercise significantly reduced triglyceride and low-density lipoprotein levels in the normal exercise group(P=0.019,P=0.008)as well as triglyceride levels in the diabetic exercise group(P=0.022).Both interleukin-6 and tumor necrosis factor α levels were significantly increased in the skeletal muscle of type 2 diabetic rats compared with the normal control group(P<0.001,P=0.007),and aerobic exercise significantly reduced tumor necrosis factor α levels in the diabetic exercise group(P=0.017).The LC3-Ⅱ/LC3-I was significantly increased in the skeletal muscle of type 2 diabetic rats compared with the normal control group.Aerobic exercise significantly increased the LC3-Ⅱ/LC3-I in the normal exercise group(P<0.001)and decreased the LC3-Ⅱ/LC3-I,FoxO3 and p62 protein expression levels in the diabetic exercise group(P=0.026,P=0.050,P=0.048).To conclusion,type 2 diabetes model established by high-fat feeding combined with streptozotocin injection has obvious glycolipid metabolism disorder,and leads to inflammatory response and excessive activation of autophagy in skeletal muscle.Aerobic exercise can improve glycolipid metabolism,reduce local inflammation in skeletal muscle and inhibit autophagy,and finally play a protective role in skeletal muscle.

16.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1024373

RESUMO

Objective To compare the clinical efficacies of video-assisted thoracoscopic segmentectomy versus lobectomy for early-stage non-small cell lung cancer.Methods The clinical data of 234 patients with stage ⅠA non-small cell lung cancer and undergoing different surgical methods under video-assisted thoracoscopy admitted to Chongqing Dianjiang General Hospital were retrospectively analyzed,and the patients were divided into the lung segment group and the lung lobe group according to their surgical methods.The clinical characteristics of the patients in the two groups were balanced by a 1-to-1 ratio matching through the propensity score matching method,and each group finally included 63 cases.The perioperative indicators containing operation time,intraoperative blood loss,postoperative thoracic drainage tube indwelling time,thoracic drainage volumes 24 hours and 48 hours after operation and postoperative hospital stay were compared of patients between the two groups.The incidence of postoperative complications such as air leakage>6 days,pulmonary infection,atelectasis,hemoptysis,and hoarseness in the two groups was collected.Results There was no significant difference in the operation time,intraoperative blood loss,thoracic drainage volumes 24 hours and 48 hours after operation,postoperative thoracic drainage tube indwelling time or incidence of postoperative complications of patients between the two groups(P>0.05).The postoperative hospital stay of patients in the lung segment group was shorter than that in the lung lobe group,with statistically significant difference(P=0.003).Conclusion For patients with stage ⅠA non-small cell lung cancer,video-assisted thoracoscopic segmentectomy has similar perioperative efficacy to lobectomy,while segmentectomy has a more significant advantage in shortening the hospital stay.

17.
Iran J Parasitol ; 18(3): 382-389, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37886258

RESUMO

Background: The pathogen of angiostrongyliasis is the parasite Angiostrongylus cantonensis, and the transcriptome profiling of the male adult was unclear. We aimed to understand how the male adults adapt, so the expression profile of A. cantonensis adult males was analyzed. Methods: In order to improve the understanding of the transcriptome of adult males, RNA from three groups of male adult A. cantonensis was extracted and reverse transcribed to construct cDNA libraries. After sequencing, annotation of unigenes and transcripts was performed by querying the NR (Non-Redundant Protein Sequence Database), GO (Gene Ontology) and COG/KOG (Clusters of Orthologous Groups of proteins/euKaryotic Ortholog Groups) databases. Results: For each group of adults, 43,260,894 raw reads and 43,200,341 clean reads were obtained. After successful assembly, 87,649 unigenes and 146,895 transcripts were obtained. Annotation of the unigenes and transcripts was identical and male adults expressed a series of genes encoding proteins specific to the male gender at the adult stage, such as proteins involved in energy metabolism, energy synthesis and transport. Expression of the ribosome pathway suggests a relationship with the physical activities during the adult male stage. Conclusion: The transcriptome analysis is a good reference to understand further the expression profile of male adult A. cantonensis.

18.
Natl Sci Rev ; 10(11): nwad226, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37818117

RESUMO

Electrocatalytic CO2 reduction (ECR) coupled with organic oxidation is a promising strategy to produce high value-added chemicals and improve energy efficiency. However, achieving the efficient redox coupling reaction is still challenging due to the lack of suitable electrocatalysts. Herein, we designed two bifunctional polyimides-linked covalent organic frameworks (PI-COFs) through assembling phthalocyanine (Pc) and porphyrin (Por) by non-toxic hydrothermal methods in pure water to realize the above catalytic reactions. Due to the high conductivity and well-defined active sites with different chemical environments, NiPc-NiPor COF performs efficient ECR coupled with methanol oxidation reaction (MOR) (Faradaic efficiency of CO (FECO) = 98.12%, partial current densities of CO (jCO) = 6.14 mA cm-2 for ECR, FEHCOOH = 93.75%, jHCOOH = 5.81 mA cm-2 for MOR at low cell voltage (2.1 V) and remarkable long-term stability). Furthermore, experimental evidences and density functional theory (DFT) calculations demonstrate that the ECR process mainly conducts on NiPc unit with the assistance of NiPor, meanwhile, the MOR prefers NiPor conjugating with NiPc. The two units of NiPc-NiPor COF collaboratively promote the coupled oxidation-reduction reaction. For the first time, this work achieves the rational design of bifunctional COFs for coupled heterogeneous catalysis, which opens a new area for crystalline material catalysts.

19.
Genomics ; 115(5): 110707, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37722434

RESUMO

The role of lncRNAs in the regeneration of fibrotic liver is unclear. To address this issue, we established a 70% hepatectomy model of liver fibrosis in mice, used high-throughput sequencing technology to obtain the expression profiles of lncRNAs, miRNAs, and mRNAs, and constructed a lncRNA-miRNA-mRNA regulatory network. A total of 1329 lncRNAs, 167 miRNAs, and 6458 mRNAs were differentially expressed. On this basis, a lncRNA-miRNA-mRNA ceRNA regulatory network consisting of 38 DE lncRNAs, 24 DE miRNAs, and 299 DE mRNAs was constructed, and a transcription factor (TF) - mRNA regulatory network composed of 20 TFs and 98 DE mRNAs was built. Through the protein network analysis, a core protein interaction network composed of 20 hub genes was derived. Furthermore, Xist/miR-144-3p/Cdc14b and Snhg3/miR-365-3p/Map3k14 axes in the ceRNA regulatory network were verified by Real-Time quantitative PCR. Therefore, we concluded that these new insights may further our understanding of liver regeneration.

20.
Angew Chem Int Ed Engl ; 62(36): e202308505, 2023 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-37435787

RESUMO

Photocatalytic synthesis of hydrogen peroxide (H2 O2 ) is a potential clean method, but the long distance between the oxidation and reduction sites in photocatalysts hinders the rapid transfer of photogenerated charges, limiting the improvement of its performance. Here, a metal-organic cage photocatalyst, Co14 (L-CH3 )24 , is constructed by directly coordinating metal sites (Co sites) used for the O2 reduction reaction (ORR) with non-metallic sites (imidazole sites of ligands) used for the H2 O oxidation reaction (WOR), which shortens the transport path of photogenerated electrons and holes, and improves the transport efficiency of charges and activity of the photocatalyst. Therefore, it can be used as an efficient photocatalyst with a rate of as high as 146.6 µmol g-1 h-1 for H2 O2 production under O2 -saturated pure water without sacrificial agents. Significantly, the combination of photocatalytic experiments and theoretical calculations proves that the functionalized modification of ligands is more conducive to adsorbing key intermediates (*OH for WOR and *HOOH for ORR), resulting in better performance. This work proposed a new catalytic strategy for the first time; i.e., to build a synergistic metal-nonmetal active site in the crystalline catalyst and use the host-guest chemistry inherent in the metal-organic cage (MOC)to increase the contact between the substrate and the catalytically active site, and finally achieve efficient photocatalytic H2 O2 synthesis.

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