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1.
J Environ Sci (China) ; 149: 234-241, 2025 Mar.
Article in English | MEDLINE | ID: mdl-39181638

ABSTRACT

Reducing the cost of RuO2/TiO2 catalysts is still one of the urgent challenges in catalytic HCl oxidation. In the present work, a Ce-doped TiO2 supported RuO2 catalyst with a low Ru loading was developed, showing a high activity in the catalytic oxidation of HCl to Cl2. The results on some extensive characterizations of both Ce-doped TiO2 carriers and their supported RuO2 catalysts show that the doping of Ce into TiO2 can effectively change the lattice parameters of TiO2 to improve the dispersion of the active RuO2 species on the carrier, which facilitates the production of surface Ru species to expose more active sites for boosting the catalytic performance even under some harsh reaction conditions. This work provides some scientific basis and technical support for chlorine recycling.


Subject(s)
Cerium , Hydrochloric Acid , Oxidation-Reduction , Titanium , Titanium/chemistry , Catalysis , Cerium/chemistry , Hydrochloric Acid/chemistry , Ruthenium Compounds/chemistry , Chlorides/chemistry , Models, Chemical , Chlorine/chemistry
2.
Perioper Med (Lond) ; 13(1): 96, 2024 Oct 04.
Article in English | MEDLINE | ID: mdl-39367478

ABSTRACT

BACKGROUND: A systematic review and network meta-analysis (NMA) to compare the safety and efficacy of pericapsular nerve group block (PENGB) with other regional analgesia techniques in patients undergoing total hip arthroplasty (THA). METHODS: We searched PubMed, Embase, Web of Science, and the Cochrane Library for relevant research from inception to May, 2024. Randomized controlled trials (RCTs) comparing PENGB with other regional analgesia techniques in patients undergoing THA were included. The primary outcome was resting pain scores at 6 h after surgery. The NMA was made by using Stata 15.1 software. Potential risk of bias was assessed by using CINeMA. Sensitivity and subgroup analyses were performed on the primary outcome. RESULTS: A total of 11 RCTs including 766 patients were eligible for inclusion. For postoperative resting and movement pain scores within 24 h analysis, PENGB + periarticular local anesthetic infiltration (PLAI) was found to be significantly more effective than other treatments and its Surface under the cumulative ranking curve (SUCRA) was the lowest. Moreover, PENGB + PLAI was ranked the best in reducing opioid consumption within 24 h and the length of hospital stay. PENGB was found to have significantly lower incidence of quadriceps motor block and postoperative nausea and vomiting (PONV). CONCLUSIONS: PENGB is more likely to reduce the incidence of quadriceps motor block and PONV in patients undergoing THA, but PENGB + PLAI is superior to other regional analgesia techniques (PLAI, PENGB, fascia iliaca compartment block, and quadratus lumborum block) in improving postoperative pain and shortening the length of hospital stay. TRIAL REGISTRATION NUMBER: CRD42024538421.

3.
J Org Chem ; 89(19): 14164-14176, 2024 Oct 04.
Article in English | MEDLINE | ID: mdl-39291865

ABSTRACT

Based on rich sulfur-involving chemical transformations, a novel spokewise synthetic strategy, a subclass of the collective strategies, has been developed to concisely synthesize four erythrina alkaloids through a single-step transformation from a common synthetic precursor. Moreover, six additional erythrina alkaloids have also been synthesized by subsequent 1-2 steps chemical transformations. The current synthetic approaches provide a valuable platform for collective total syntheses of erythrina alkaloids and pseudo-natural erythrina alkaloids.

4.
Chem Sci ; 2024 Sep 03.
Article in English | MEDLINE | ID: mdl-39296994

ABSTRACT

An unusual cascade C-H activation, vinylation and 6π-electrocyclization of 2-pyridyl aldimines with vinyl bromides/triflates was achieved using catalysis with a unique CCC pincer NHC-Ru(iii) complex (Cat B). This reaction was found to enable a rapid and diverse synthesis of polycyclic 4H-pyrido[1,2-a]pyrimidine derivatives in mostly good to high yields, and with a broad substrate scope. A mechanistic study suggested the formation of a semi-opened Ru(iii) intermediate chelating/activating the aldimine, and the occurrence of single-electron transfer (SET) to generate a vinyl radical, followed by vinylation and then an intramolecular 6π-electrocyclization of 1N,3N-hexatrene to form the product. This protocol provides a convenient approach for preparing and seeking new drug candidates.

5.
Chemistry ; : e202402757, 2024 Sep 06.
Article in English | MEDLINE | ID: mdl-39242340

ABSTRACT

The direct hydrogenation of 2-nitroacylbenzene to 2,1-benzisoxazole presents a significant challenge in the pharmaceutical and fine chemicals industries. In this study, a defect engineering strategy is employed to create bifunctional single-atom catalysts (SACs) by anchoring Pt single atoms onto metal vacancies within MgO(Al) nanosheets. The resultant Pt1/MgO(Al) SAC displays an exceptional catalytic activity and selectivity in the hydrogenation-cyclization of 2-nitroacylbenzene, achieving a 97.5% yield at complete conversion and a record-breaking turnover frequency of 458.8 h-1 under the mild conditions. The synergistic catalysis between the fully exposed single-atom Pt sites within a unique Pt-O-Mg/Al moiety and the abundant basic sites of the MgO(Al) support is responsible for this outstanding catalytic performance. The current work, therefore, paves the way for developing bifunctional or multifunctional SACs that can enhance efficient organocatalytic conversions.

6.
J Am Chem Soc ; 146(37): 25445-25450, 2024 Sep 18.
Article in English | MEDLINE | ID: mdl-39235150

ABSTRACT

To date, it remains challenging to precisely and efficiently construct structurally intriguing polycarbocycles with densely packed stereocenters in organic synthesis. Niduterpenoid B, a naturally occurring ERα inhibitor, exemplifies this complexity with its intricate polycyclic network comprising 5 cyclopentane and 1 cyclopropane rings, featuring 13 contiguous stereocenters, including 4 all-carbon quaternary centers. In this work, we describe the first total synthesis of niduterpenoid B using a structural reorganization strategy. Key features include the following: (1) an efficient methoxy-controlled cascade reaction that precisely forges a highly functionalized tetraquinane (A-D rings) bearing sterically hindered contiguous quaternary stereocenters; (2) a rhodium-catalyzed [1 + 2] cycloaddition that facilitates the construction of a strained 3/5 bicycle (E-F rings) angularly fused with ring D.

7.
Dig Endosc ; 2024 Sep 10.
Article in English | MEDLINE | ID: mdl-39253829

ABSTRACT

OBJECTIVES: Although the incidence of isolated gastric varices type 1 (IGV1) bleeding is low, the condition is highly dangerous and associated with high mortality, making its treatment challenging. We aimed to compare the safety and efficacy of endoscopic clipping combined with cyanoacrylate injection (EC-CYA) vs. transjugular intrahepatic portosystemic shunt (TIPS) in treating IGV1. METHODS: In a single-center, randomized controlled trial, patients with IGV1 bleeding were randomly assigned to the EC-CYA group or TIPS group. The primary end-points were gastric variceal rebleeding rates and technical success. Secondary end-points included cumulative nonbleeding rates, mortality, and complications. RESULTS: A total of 156 patients between January 2019 and April 2023 were selected and randomly assigned to the EC-CYA group (n = 76) and TIPS group (n = 80). The technical success rate was 100% for both groups. The rebleeding rates were 14.5% in the EC-CYA group and 8.8% in the TIPS group, showing no significant difference (P = 0.263). Kaplan-Meier analysis revealed that the cumulative nonbleeding rates at 6, 12, 24, and 36 months for the two groups lacked statistical significance (P = 0.344). Similarly, cumulative survival rates at 12, 24, and 36 months for the two groups were not statistically significant (P = 0.916). The bleeding rates from other causes were 13.2% and 6.3% for the respective groups, showing no significant difference (P = 0.144). No instances of ectopic embolism were observed in either group. The incidence of hepatic encephalopathy (HE) in the TIPS group was statistically higher than that in the EC-CYA group (P = 0.001). CONCLUSION: Both groups are effective in controlling IGV1 bleeding. Notably, EC-CYA did not result in ectopic embolism, and the incidence of HE was lower than that observed with TIPS.

8.
Chem Commun (Camb) ; 60(73): 9954-9957, 2024 Sep 10.
Article in English | MEDLINE | ID: mdl-39177032

ABSTRACT

A catalytic asymmetric α-hydroxylation of pyridinone-fused lactones, containing the core structure of camptothecin, is described. Development of a novel spiropyrrolidine amide (SPA) derived triazolium bromide organo-cation catalyst is crucial for a highly enantioselective oxidation, which also accommodates a wide array of lactones with various substituents. The resulting tricyclic tertiary alcohol with an oxa-quaternary carbon center can be further applied in the synthesis of SN-38 and irinotecan, two anti-cancer drugs derived from camptothecin.

9.
Angew Chem Int Ed Engl ; : e202412337, 2024 Aug 06.
Article in English | MEDLINE | ID: mdl-39106111

ABSTRACT

A cascade Nazarov cyclization/dicycloexpansions reaction was developed for the precise synthesis of the angularly fused M/5/N (M = 5, 6; N = 4-9, 13) tricyclic skeletons. The prioritized expansion of the first ring played a critical role in the transformations, due to the release of ring strain, and the nature of the substituents present on the substrate is another influencing factor. This pioneering cascade reaction features broad substrates scope (33 examples), short reaction time, exceptional yields (up to 95%), and remarkable regioselectivities (> 20:1). Exploiting the synthetic application of this cascade reaction, we successfully executed a succinct total synthesis of nominal madreporanone for the first time.

10.
Surg Laparosc Endosc Percutan Tech ; 34(5): 518-523, 2024 Oct 01.
Article in English | MEDLINE | ID: mdl-39056236

ABSTRACT

OBJECTIVE: The purpose of this study was to investigate the efficacy and safety of endoscopic ultrasound (EUS)-guided injection of cyanoacrylate (CYA) and transjugular intrahepatic portal shunts (TIPSs) in the treatment of patients with cirrhosis with ruptured gastric varices. METHODS: In this retrospective study, 105 patients with liver cirrhosis and gastric varicose veins who were admitted to the First Affiliated Hospital of Anhui Medical University between April 2018 and April 2023 without nonselective ß-blockers treatment and no portal vein thrombosis were evaluated. The patients were divided into the transjugular intrahepatic portal shunt (TIPS) group (n = 60) and the EUS-CYA group (n = 45) for the purpose of evaluating postoperative rebleeding rates, complications, survival rates, and other factors. RESULTS: During the follow-up, there was no significant difference in the rebleeding rates between the TIPS group and EUS-CYA group within 3 months (5% vs 2.2%; P = 0.825; 10% vs 20%, P = 0.147). However, the TIPS group had significantly lower rebleeding rates than the EUS-CYA group at 6 months (10% vs 33.3%; P = 0.030) and 1 year or longer (11.7% vs 42.2%; P < 0.01). In terms of hepatic encephalopathy, the incidence rate of the TIPS group was significantly higher than that of the EUS-CYA group (20% vs 2.2%; P = 0.006). In addition, there was no difference in the survival rates between the two groups (93.3% vs 97.8%; P = 0.552). CONCLUSIONS: TIPS is superior to EUS in preventing rebleeding in patients with ruptured varices of the fundus, but it has a higher incidence of hepatic encephalopathy, and there is no difference in long-term survival between the two groups.


Subject(s)
Cyanoacrylates , Endosonography , Esophageal and Gastric Varices , Gastrointestinal Hemorrhage , Portasystemic Shunt, Transjugular Intrahepatic , Humans , Male , Female , Portasystemic Shunt, Transjugular Intrahepatic/methods , Esophageal and Gastric Varices/therapy , Retrospective Studies , Middle Aged , Cyanoacrylates/administration & dosage , Gastrointestinal Hemorrhage/prevention & control , Gastrointestinal Hemorrhage/etiology , Recurrence , Liver Cirrhosis/complications , Adult , Aged , Treatment Outcome , Ultrasonography, Interventional , Secondary Prevention/methods
11.
Mol Biol Evol ; 41(6)2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38768215

ABSTRACT

High mountains harbor a considerable proportion of biodiversity, but we know little about how diverse plants adapt to the harsh environment. Here we finished a high-quality genome assembly for Dasiphora fruticosa, an ecologically important plant distributed in the Qinghai-Tibetan Plateau and lowland of the Northern Hemisphere, and resequenced 592 natural individuals to address how this horticulture plant adapts to highland. Demographic analysis revealed D. fruticosa underwent a bottleneck after Naynayxungla Glaciation. Selective sweep analysis of two pairs of lowland and highland populations identified 63 shared genes related to cell wall organization or biogenesis, cellular component organization, and dwarfism, suggesting parallel adaptation to highland habitats. Most importantly, we found that stronger purging of estimated genetic load due to inbreeding in highland populations apparently contributed to their adaptation to the highest mountain. Our results revealed how plants could tolerate the extreme plateau, which could provide potential insights for species conservation and crop breeding.


Subject(s)
Genome, Plant , Selection, Genetic , Adaptation, Physiological/genetics , Altitude
12.
ACS Appl Mater Interfaces ; 16(11): 13839-13848, 2024 Mar 20.
Article in English | MEDLINE | ID: mdl-38446719

ABSTRACT

The application of covalent organic frameworks (COFs) for the photocatalytic reduction of CO2 is mostly limited by severe charge recombination and low sunlight utilization. Herein, a triazine-based COF with an electron-rich and large π-conjugated system (TCOF) was employed as a building block and integrated with CuInS2 (CIS) to construct a noble-metal-free and high-efficiency photocatalyst for CO2 reduction. The in situ growth of CIS nanosheets on TCOF creates a p-n heterojunction, named CIS@TCOF. Compared with TCOF, the CIS@TCOF heterostructure exhibits a dramatically boosted photocatalytic performance in the reduction of CO2. The produced HCOOH yield over 10 wt % CIS@TCOF can be up to 171.2 µmol g-1 h-1 under visible light irradiation with good reproducibility, which is about 3 times as high as that over TCOF. Further in-depth studies indicate that the introduction of CIS not only enhances the visible light utilization but also restrains the recombination of photogenerated electron-hole pairs efficiently and facilitates the photoinduced charge transfer via the p-n heterojunction system due to the unique structural and compositional features. This research shows the great potential of COFs as efficient photocatalytic carbon fixation materials and provides a versatile route to construct semiconductor-COF heterostructures for photocatalysis.

13.
Mol Ecol ; 33(5): e17268, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38230514

ABSTRACT

Ecological divergence due to habitat difference plays a prominent role in the formation of new species, but the genetic architecture during ecological speciation and the mechanism underlying phenotypic divergence remain less understood. Two wild ancestors of rice (Oryza rufipogon and Oryza nivara) are a progenitor-derivative species pair with ecological divergence and provide a unique system for studying ecological adaptation/speciation. Here, we constructed a high-resolution linkage map and conducted a quantitative trait locus (QTL) analysis of 19 phenotypic traits using an F2 population generated from a cross between the two Oryza species. We identified 113 QTLs associated with interspecific divergence of 16 quantitative traits, with effect sizes ranging from 1.61% to 34.1% in terms of the percentage of variation explained (PVE). The distribution of effect sizes of QTLs followed a negative exponential, suggesting that a few genes of large effect and many genes of small effect were responsible for the phenotypic divergence. We observed 18 clusters of QTLs (QTL hotspots) on 11 chromosomes, significantly more than that expected by chance, demonstrating the importance of coinheritance of loci/genes in ecological adaptation/speciation. Analysis of effect direction and v-test statistics revealed that interspecific differentiation of most traits was driven by divergent natural selection, supporting the argument that ecological adaptation/speciation would proceed rapidly under coordinated selection on multiple traits. Our findings provide new insights into the understanding of genetic architecture of ecological adaptation and speciation in plants and help effective manipulation of specific genes or gene cluster in rice breeding.


Subject(s)
Oryza , Oryza/genetics , Plant Breeding , Chromosome Mapping , Phenotype , Quantitative Trait Loci/genetics
14.
Circ Cardiovasc Interv ; 17(2): e013455, 2024 02.
Article in English | MEDLINE | ID: mdl-38258563

ABSTRACT

BACKGROUND: It is uncertain whether adjunctive thrombolysis is beneficial for patients with ST-segment-elevation myocardial infarction undergoing percutaneous coronary intervention (PCI) within 120 minutes of presentation. This study was to determine whether in patients presenting with ST-segment-elevation myocardial infarction a single bolus recombinant staphylokinase (r-SAK) before timely PCI leads to improved patency of the infarct-related artery and reduces the infarct size. METHODS: This is an open-label, prospective, multicenter, randomized study. We enrolled patients aged 18 to 75 years who were within 12 hours of symptom onset of ST-segment-elevation myocardial infarction and expected to undergo PCI within 120 minutes. Patients were administered loading doses of aspirin and ticagrelor and intravenous heparin and were randomized to receive 5 mg bolus of r-SAK or normal saline intravenously before PCI. The primary end point was Thrombolysis in Myocardial Infarction flow grade 2 to 3 or grade 3 in the infarct-related artery 60 minutes after thrombolysis. The infarct size was detected by cardiac magnetic resonance 5 days after randomization. The safety end point was major bleeding (Bleeding Academic Research Consortium ≥3) during 30-day follow-up. RESULTS: A total of 283 patients were screened from 8 centers and 200 were randomized (median age, 58.5 years; 14% female). The median symptom to thrombolysis time was 252.5 (interquartile range, 142.8-423.8) minutes and thrombolysis to coronary arteriography was 50.0 (interquartile range, 37.0-66.0) minutes. Patients randomized to r-SAK compared with normal saline more often had Thrombolysis in Myocardial Infarction flow grade 2 to 3 (69.0% versus 29.0%; P<0.001) and Thrombolysis in Myocardial Infarction flow grade 3 (51.0% versus 18.0%; P<0.001) and had smaller infarct size (21.91±10.84% versus 26.85±12.37%; P=0.016). There was no increase in major bleeding (r-SAK, 1.0% versus control, 3.0%; P=0.616). CONCLUSIONS: A single bolus r-SAK before primary PCI for ST-segment-elevation myocardial infarction improves infarct-related artery patency and reduces infarct size without increasing major bleeding. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT05023681.


Subject(s)
Metalloendopeptidases , Myocardial Infarction , Percutaneous Coronary Intervention , ST Elevation Myocardial Infarction , Female , Humans , Male , Middle Aged , Hemorrhage/chemically induced , Myocardial Infarction/etiology , Percutaneous Coronary Intervention/adverse effects , Prospective Studies , Saline Solution/therapeutic use , ST Elevation Myocardial Infarction/diagnostic imaging , ST Elevation Myocardial Infarction/therapy , ST Elevation Myocardial Infarction/etiology , Treatment Outcome , Adolescent , Young Adult , Adult , Aged
15.
Surg Endosc ; 38(2): 633-639, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38012437

ABSTRACT

OBJECTIVE: The present study aimed to investigate the accuracy of endoscopic ultrasonography (EUS) combined with Indian ink in locating target vessels of gastric varices (GVs) compared with conventional endoscopic techniques. Additionally, the characteristics of GVs under conventional endoscopy were also explored. METHODS: All 50 cirrhotic patients with GVs between August 2021 and December 2022 were included in the study. Firstly, conventional endoscopy was employed to identify GVs and to record the expected injection sites. Subsequently, EUS was used to locate the perforated vessel and the injection site was them marked with India ink followed by injection with cyanoacrylate (CYA). Finally, conventional endoscopy was used to examine GVs, to identify the marker points of Indian ink and to compare whether the injection points under conventional endoscopy were consistent with those marked with Indian ink. Furthermore, patients with consistent and inconsistent distribution of endoscopic markers and injection sites were divided into two groups. RESULTS: EUS could detect the perforating vessels in real time and intuitively. The distribution of markers using EUS was significantly different compared with the injection points obtained by conventional endoscopy (P < 0.001). Therefore, 20 cases were allocated to the consistent group and 30 cases to the non-consistent group. 16 patients who showed red wale signs were obtained in the consistent group and 11 patients in the non-consistent group (P = 0.048). The diameter of the largest GVs was 13.5 (10-15) mm in the consistent group compared with 10 (7.5-10) mm in the non-consistent group (P = 0.006). CONCLUSION: EUS could provide the exact location of GVs, thus more accurately describing the endoscopic characteristics of the GVs. Furthermore, the red wale signs and diameter of the largest GVs obtained using conventional endoscopy were helpful in determining the location of target GVs.


Subject(s)
Endosonography , Esophageal and Gastric Varices , Humans , Endosonography/methods , Esophageal and Gastric Varices/diagnostic imaging , Esophageal and Gastric Varices/etiology , Ink , Cyanoacrylates , Endoscopy, Gastrointestinal , Gastrointestinal Hemorrhage
16.
Nanoscale Adv ; 5(24): 7087, 2023 Dec 05.
Article in English | MEDLINE | ID: mdl-38059032

ABSTRACT

[This corrects the article DOI: 10.1039/D3NA90045B.][This corrects the article DOI: 10.1039/D2NA00758D.].

17.
Chem Commun (Camb) ; 59(97): 14427-14430, 2023 Dec 05.
Article in English | MEDLINE | ID: mdl-37975863

ABSTRACT

A photoinduced reductive Reformatsky reaction by cooperative dual-metal catalysis is described. This methodology enables the implementation of this venerable reaction in environmentally friendly conditions, obviating the need for a stoichiometric amount of metals. A broad range of synthetically useful ß-hydroxy esters can be efficiently prepared in moderate to high yields using this protocol.

18.
Chaos ; 33(11)2023 Nov 01.
Article in English | MEDLINE | ID: mdl-37967264

ABSTRACT

This study presents a general framework, namely, Sparse Spatiotemporal System Discovery (S3d), for discovering dynamical models given by Partial Differential Equations (PDEs) from spatiotemporal data. S3d is built on the recent development of sparse Bayesian learning, which enforces sparsity in the estimated PDEs. This approach enables a balance between model complexity and fitting error with theoretical guarantees. The proposed framework integrates Bayesian inference and a sparse priori distribution with the sparse regression method. It also introduces a principled iterative re-weighted algorithm to select dominant features in PDEs and solve for the sparse coefficients. We have demonstrated the discovery of the complex Ginzburg-Landau equation from a traveling-wave convection experiment, as well as several other PDEs, including the important cases of Navier-Stokes and sine-Gordon equations, from simulated data.

19.
J Am Chem Soc ; 145(49): 26550-26556, 2023 Dec 13.
Article in English | MEDLINE | ID: mdl-38019148

ABSTRACT

A catalytic enantioselective polycyclization of tertiary enamides with terminal silyl enol ethers has been developed by virtue of Cu(OTf)2 catalysis with a novel spiropyrroline-derived oxazole (SPDO) ligand. This tandem reaction offers an effective approach to assemble bicyclic and tricyclic N-heterocycles bearing both aza- and oxa-quaternary stereogenic centers, which are primal subunits in a range of natural alkaloids. Strategic application of this methodology and a late-stage radical cyclization as key steps have been showcased in the concise total synthesis of (-)-cephalocyclidin A.

20.
J Org Chem ; 88(20): 14670-14675, 2023 Oct 20.
Article in English | MEDLINE | ID: mdl-37815481

ABSTRACT

An asymmetric [3+2] cycloaddition of quinone esters with 2,3-dihydrofuran has been realized via a newly developed Cu(II)/SPDO complex. It provides straightforward access to 2,3,3a,8a-tetrahydrofuro[2,3-b]benzofurans (TFB) with high enantioselectivity (up to 97.5:2.5 er) and diastereoselectivity (all >20:1 dr). The resulting adducts contain two adjacent stereocenters and a continuously functionalized benzene ring. Additionally, this transformation could be easily performed on a gram scale, allowing for expedient synthesis of natural dihydroaflatoxin D2 and aflatoxin B2.

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