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1.
Lancet ; 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38599220

RESUMO

BACKGROUND: Following percutaneous coronary intervention with stent placement to treat acute coronary syndromes, international clinical guidelines generally recommend dual antiplatelet therapy with aspirin plus a P2Y12 receptor inhibitor for 12 months to prevent myocardial infarction and stent thrombosis. However, data on single antiplatelet therapy with a potent P2Y12 inhibitor earlier than 12 months after percutaneous coronary intervention for patients with an acute coronary syndrome are scarce. The aim of this trial was to assess whether the use of ticagrelor alone, compared with ticagrelor plus aspirin, could reduce the incidence of clinically relevant bleeding events without an accompanying increase in major adverse cardiovascular or cerebrovascular events (MACCE). METHODS: In this randomised, placebo-controlled, double-blind clinical trial, patients aged 18 years or older with an acute coronary syndrome who completed the IVUS-ACS study and who had no major ischaemic or bleeding events after 1-month treatment with dual antiplatelet therapy were randomly assigned to receive oral ticagrelor (90 mg twice daily) plus oral aspirin (100 mg once daily) or oral ticagrelor (90 mg twice daily) plus a matching oral placebo, beginning 1 month and ending at 12 months after percutaneous coronary intervention (11 months in total). Recruitment took place at 58 centres in China, Italy, Pakistan, and the UK. Patients were required to remain event-free for 1 month on dual antiplatelet therapy following percutaneous coronary intervention with contemporary drug-eluting stents. Randomisation was done using a web-based system, stratified by acute coronary syndrome type, diabetes, IVUS-ACS randomisation, and site, using dynamic minimisation. The primary superiority endpoint was clinically relevant bleeding (Bleeding Academic Research Consortium [known as BARC] types 2, 3, or 5). The primary non-inferiority endpoint was MACCE (defined as the composite of cardiac death, myocardial infarction, ischaemic stroke, definite stent thrombosis, or clinically driven target vessel revascularisation), with an expected event rate of 6·2% in the ticagrelor plus aspirin group and an absolute non-inferiority margin of 2·5 percentage points between 1 month and 12 months after percutaneous coronary intervention. The two co-primary endpoints were tested sequentially; the primary superiority endpoint had to be met for hypothesis testing of the MACCE outcome to proceed. All principal analyses were assessed in the intention-to-treat population. This trial is registered with ClinicalTrials.gov, NCT03971500, and is completed. FINDINGS: Between Sept 21, 2019, and Oct 27, 2022, 3400 (97·0%) of the 3505 participants in the IVUS-ACS study were randomly assigned (1700 patients to ticagrelor plus aspirin and 1700 patients to ticagrelor plus placebo). 12-month follow-up was completed by 3399 (>99·9%) patients. Between month 1 and month 12 after percutaneous coronary intervention, clinically relevant bleeding occurred in 35 patients (2·1%) in the ticagrelor plus placebo group and in 78 patients (4·6%) in the ticagrelor plus aspirin group (hazard ratio [HR] 0·45 [95% CI 0·30 to 0·66]; p<0·0001). MACCE occurred in 61 patients (3·6%) in the ticagrelor plus placebo group and in 63 patients (3·7%) in the ticagrelor plus aspirin group (absolute difference -0·1% [95% CI -1·4% to 1·2%]; HR 0·98 [95% CI 0·69 to 1·39]; pnon-inferiority<0·0001, psuperiority=0·89). INTERPRETATION: In patients with an acute coronary syndrome who had percutaneous coronary intervention with contemporary drug-eluting stents and remained event-free for 1 month on dual antiplatelet therapy, treatment with ticagrelor alone between month 1 and month 12 after the intervention resulted in a lower rate of clinically relevant bleeding and a similar rate of MACCE compared with ticagrelor plus aspirin. Along with the results from previous studies, these findings show that most patients in this population can benefit from superior clinical outcomes with aspirin discontinuation and maintenance on ticagrelor monotherapy after 1 month of dual antiplatelet therapy. FUNDING: The Chinese Society of Cardiology, the National Natural Scientific Foundation of China, and the Jiangsu Provincial & Nanjing Municipal Clinical Trial Project. TRANSLATION: For the Mandarin translation of the abstract see Supplementary Materials section.

2.
Org Lett ; 26(15): 3310-3315, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38587335

RESUMO

A catalyst system consisting of a chiral phosphoramidite ligand and Pd2(dba)3·CHCl3 causes the decarboxylation of 5-vinyloxazolidine-2,4-diones to generate amide-containing aza-π-allylpalladium 1,3-dipole intermediates, which are capable of triggering the dearomatization of 3-nitroindoles for diastereo- and enantioselective [3+2] cycloaddition, leading to the formation of a series of highly functionalized pyrroloindolines containing three contiguous stereogenic centers with excellent results (up to 99% yield, 88:12 dr, and 96% ee).

3.
Lancet ; 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38604212

RESUMO

BACKGROUND: Intravascular ultrasound-guided percutaneous coronary intervention has been shown to result in superior clinical outcomes compared with angiography-guided percutaneous coronary intervention. However, insufficient data are available concerning the advantages of intravascular ultrasound guidance for patients with an acute coronary syndrome. This trial aimed to investigate whether the use of intravascular ultrasound guidance, as compared with angiography guidance, improves the outcomes of percutaneous coronary intervention with contemporary drug-eluting stents in patients presenting with an acute coronary syndrome. METHODS: In this two-stage, multicentre, randomised trial, patients aged 18 years or older and presenting with an acute coronary syndrome at 58 centres in China, Italy, Pakistan, and the UK were randomly assigned to intravascular ultrasound-guided percutaneous coronary intervention or angiography-guided percutaneous coronary intervention. Patients, follow-up health-care providers, and assessors were masked to random assignment; however, staff in the catheterisation laboratory were not. The primary endpoint was target vessel failure, a composite of cardiac death, target vessel myocardial infarction, or clinically driven target vessel revascularisation at 1 year after randomisation. This trial is registered at ClinicalTrials.gov, NCT03971500, and is completed. FINDINGS: Between Aug 20, 2019 and Oct 27, 2022, 3505 patients with an acute coronary syndrome were randomly assigned to intravascular ultrasound-guided percutaneous coronary intervention (n=1753) or angiography-guided percutaneous coronary intervention (n=1752). 1-year follow-up was completed in 3504 (>99·9%) patients. The primary endpoint occurred in 70 patients in the intravascular ultrasound group and 128 patients in the angiography group (Kaplan-Meier rate 4·0% vs 7·3%; hazard ratio 0·55 [95% CI 0·41-0·74]; p=0·0001), driven by reductions in target vessel myocardial infarction or target vessel revascularisation. There were no significant differences in all-cause death or stent thrombosis between groups. Safety endpoints were also similar in the two groups. INTERPRETATION: In patients with an acute coronary syndrome, intravascular ultrasound-guided implantation of contemporary drug-eluting stents resulted in a lower 1-year rate of the composite outcome of cardiac death, target vessel myocardial infarction, or clinically driven revascularisation compared with angiography guidance alone. FUNDING: The Chinese Society of Cardiology, the National Natural Scientific Foundation of China, and Jiangsu Provincial & Nanjing Municipal Clinical Trial Project. TRANSLATION: For the Mandarin translation of the abstract see Supplementary Materials section.

4.
Front Pharmacol ; 15: 1349032, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38549672

RESUMO

In China, Russia, Mongolia, Japan, North Korea, and Mexico, Sedum aizoon L. (S. aizoon) is used as an edible plant. Up to now, over 234 metabolites, including phenolic acids, flavonoids, triterpenes, phytosterols, and alkaloids, among others, have been identified. In addition to its antioxidant, anti-inflammatory, anti-fatigue, antimicrobial, anti-cancer, and hemostatic activities, S. aizoon is used for the treatment of cardiovascular disease. This paper provides an overview of the history, botany, nutritional value, traditional use, phytochemistry, pharmacology, toxicology, and quality control of S. aizoon.

5.
Nat Commun ; 15(1): 2736, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38548785

RESUMO

Optimizing thermoelectric conversion efficiency requires the compromise of electrical and thermal properties of materials, which are hard to simultaneously improve due to the strong coupling of carrier and phonon transport. Herein, a one-pot approach realizing simultaneous second phase and Cu vacancies modulation is proposed, which is effective in synergistically optimizing thermoelectric performance in copper sulfides. Multiple lattice defects, including nanoprecipitates, dislocations, and nanopores are produced by adding a refined ratio of Sn and Se. Phonon transport is significantly suppressed by multiple mechanisms. An ultralow lattice thermal conductivity is therefore obtained. Furthermore, extra Se is added in the copper sulfide for optimizing electrical transport properties by inducing generating Cu vacancies. Ultimately, an excellent figure of merit of ~1.6 at 873 K is realized in the Cu1.992SSe0.016(Cu2SnSe4)0.004 bulk sample. The simple strategy of inducing compositional and structural modulation for improving thermoelectric parameters promotes low-cost high-performance copper sulfides as alternatives in thermoelectric applications.

6.
Phys Rev Lett ; 132(8): 083601, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38457704

RESUMO

Quantum non-Gaussianity, a more potent and highly useful form of nonclassicality, excludes all convex mixtures of Gaussian states and Gaussian parametric processes generating them. Here, for the first time, we conclusively test quantum non-Gaussian coincidences of entangled photon pairs with the Clauser-Horne-Shimony-Holt-Bell factor S=2.328±0.004 from a single quantum dot with a depth up to 0.94±0.02 dB. Such deterministically generated photon pairs fundamentally overcome parametric processes by reducing crucial multiphoton errors. For the quantum non-Gaussian depth of the unheralded (heralded) single-photon state, we achieve the value of 8.08±0.05 dB (19.06±0.29 dB). Our Letter experimentally certifies the exclusive quantum non-Gaussianity properties highly relevant for optical sensing, communication, and computation.

7.
J Am Chem Soc ; 146(12): 8727-8736, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38487899

RESUMO

The practical application of thermoelectric devices requires both high-performance n-type and p-type materials of the same system to avoid possible mismatches and improve device reliability. Currently, environmentally friendly SnTe thermoelectrics have witnessed extensive efforts to develop promising p-type transport, making it rather urgent to investigate the n-type counterparts with comparable performance. Herein, we develop a stepwise optimization strategy for improving the transport properties of n-type SnTe. First, we improve the n-type dopability of SnTe by PbSe alloying to narrow the band gap and obtain n-type transport in SnTe with halogen doping over the whole temperature range. Then, we introduce additional Pb atoms to compensate for the cationic vacancies in the SnTe-PbSe matrix, further enhancing the electron carrier concentration and electrical performance. Resultantly, the high-ranged thermoelectric performance of n-type SnTe is substantially optimized, achieving a peak ZT of ∼0.75 at 573 K with a high average ZT (ZTave) exceeding 0.5 from 300 to 823 K in the (SnTe0.98I0.02)0.6(Pb1.06Se)0.4 sample. Moreover, based on the performance optimization on n-type SnTe, for the first time, we fabricate an all-SnTe-based seven-pair thermoelectric device. This device can produce a maximum output power of ∼0.2 W and a conversion efficiency of ∼2.7% under a temperature difference of 350 K, demonstrating an important breakthrough for all-SnTe-based thermoelectric devices. Our research further illustrates the effectiveness and application potential of the environmentally friendly SnTe thermoelectrics for mid-temperature power generation.

8.
Signal Transduct Target Ther ; 9(1): 54, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38443334

RESUMO

Respiratory disease caused by coronavirus infection remains a global health crisis. Although several SARS-CoV-2-specific vaccines and direct-acting antivirals are available, their efficacy on emerging coronaviruses in the future, including SARS-CoV-2 variants, might be compromised. Host-targeting antivirals provide preventive and therapeutic strategies to overcome resistance and manage future outbreak of emerging coronaviruses. Cathepsin L (CTSL) and calpain-1 (CAPN1) are host cysteine proteases which play crucial roles in coronaviral entrance into cells and infection-related immune response. Here, two peptidomimetic α-ketoamide compounds, 14a and 14b, were identified as potent dual target inhibitors against CTSL and CAPN1. The X-ray crystal structures of human CTSL and CAPN1 in complex with 14a and 14b revealed the covalent binding of α-ketoamide groups of 14a and 14b to C25 of CTSL and C115 of CAPN1. Both showed potent and broad-spectrum anticoronaviral activities in vitro, and it is worth noting that they exhibited low nanomolar potency against SARS-CoV-2 and its variants of concern (VOCs) with EC50 values ranging from 0.80 to 161.7 nM in various cells. Preliminary mechanistic exploration indicated that they exhibited anticoronaviral activity through blocking viral entrance. Moreover, 14a and 14b exhibited good oral pharmacokinetic properties in mice, rats and dogs, and favorable safety in mice. In addition, both 14a and 14b treatments demonstrated potent antiviral potency against SARS-CoV-2 XBB 1.16 variant infection in a K18-hACE2 transgenic mouse model. And 14b also showed effective antiviral activity against HCoV-OC43 infection in a mouse model with a final survival rate of 60%. Further evaluation showed that 14a and 14b exhibited excellent anti-inflammatory effects in Raw 264.7 mouse macrophages and in mice with acute pneumonia. Taken together, these results suggested that 14a and 14b are promising drug candidates, providing novel insight into developing pan-coronavirus inhibitors with antiviral and anti-inflammatory properties.


Assuntos
COVID-19 , Hepatite C Crônica , Humanos , Animais , Camundongos , Ratos , Cães , Calpaína , Catepsina L , Antivirais/farmacologia , Vacinas contra COVID-19 , Modelos Animais de Doenças , Camundongos Transgênicos , Anti-Inflamatórios
9.
Science ; 383(6688): 1204-1209, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38484057

RESUMO

Thermoelectric cooling technology has important applications for processes such as precise temperature control in intelligent electronics. The bismuth telluride (Bi2Te3)-based coolers currently in use are limited by the scarcity of Te and less-than-ideal cooling capability. We demonstrate how removing lattice vacancies through a grid-design strategy switched PbSe from being useful as a medium-temperature power generator to a thermoelectric cooler. At room temperature, the seven-pair device based on n-type PbSe and p-type SnSe produced a maximum cooling temperature difference of ~73 kelvin, with a single-leg power generation efficiency approaching 11.2%. We attribute our results to a power factor of >52 microwatts per centimeter per square kelvin, which was achieved by boosting carrier mobility. Our demonstration suggests a path for commercial applications of thermoelectric cooling based on Earth-abundant Te-free selenide-based compounds.

10.
Adv Mater ; 36(7): e2308353, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37903494

RESUMO

Polymorphism (and its extended form - pseudopolymorphism) in solids is ubiquitous in mineralogy, crystallography, chemistry/biochemistry, materials science, and the pharmaceutical industries. Despite the difficulty of controlling (pseudo-)polymorphism, the realization of specific (pseudo-)polymorphic phases and associated boundary structures is an efficient route to enhance material performance for energy conversion and electromechanical applications. Here, this work applies the pseudopolymorphic phase (PP) concept to a thermoelectric copper sulfide, Cu2- x S (x ≤ 0.25), via CuBr2 doping. A peak ZT value of 1.25 is obtained at 773 K in Cu1.8 S + 3 wt% CuBr2 , which is 2.3 times higher than that of a pristine Cu1.8 S sample. Atomic-resolution scanning transmission electron microscopy confirms the transformation of pristine Cu1.8 S low digenite into PP-engineered high digenite, as well as the formation of (semi-)coherent interfaces between different PPs, which is expected to enhance phonon scattering. The results demonstrate that PP engineering is an effective approach for achieving improved thermoelectric performance in Cu-S compounds. It is also expected to be useful in other materials.

11.
Int Wound J ; 21(1): e14372, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37679956

RESUMO

The purpose of this meta-analysis is to determine if the application of stitching in the closed area of the knee arthroplasty remains significantly superior to that of the staples. Data sources: EMBASE, Cochrane Libraryand, publications, and the Web of Science. Patients were treated with staples for closure of their wounds, or with conventional stitches for closure of wounds. The main findings were surgical site infection, wound dehiscence, and cutting time. The secondary results were the time to completion, the duration of the hospitalization, and the time to discharge. We incorporated the SIX trial into the meta-analyses with Review Manager V.5.3. The hazard ratio was computed as a therapeutic outcome with respect to the heterogeneity. For more than 50% of heterogeneous samples, we employed a stochastic effect model. The results showed that there was no significant difference in the degree of infection, the degree of dehiscence, the length of the cut and the degree of satisfaction of the wound. But the time to close the wound and the time to operate were significantly different. The time needed to close the wound was shorter than that of the suture (OR, -227. 22; 95% CI, -238. 74, -215. 69 p < 0. 0001); The time taken to replace the knee was also significantly lower among those who had been stapled sutures (OR, -5.46; 95% CI, -10. 43, -0.49 p = 0. 03). Wound closing materials are an afterthought for many orthopaedic surgeons. Together, the findings from a number of comparative studies indicate that the selection of wound closure materials might affect the outcome of the surgery. The evidence, however, is weak because of the heterogeneous approach adopted in earlier research. This study program is intended to provide guidance on how to select the best wound closure material for the purpose of identifying if there is any difference in the incidence of injuries among traditional stitches and staples.


Assuntos
Artroplastia do Joelho , Técnicas de Sutura , Humanos , Técnicas de Sutura/efeitos adversos , Grampeamento Cirúrgico/efeitos adversos , Artroplastia do Joelho/efeitos adversos , Artroplastia do Joelho/métodos , Infecção da Ferida Cirúrgica/etiologia , Suturas/efeitos adversos
12.
Biochim Biophys Acta Mol Basis Dis ; 1870(2): 166979, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38065272

RESUMO

Heart failure (HF) with preserved ejection fraction (HFpEF) is now the most common form of HF and has been reported to be closely related to diabetes. Accumulating evidence suggests that HFpEF patients exhibit cardiac fibrosis. This study investigates whether direct targeted inhibition of the activation of cardiac fibroblasts (CFs), the main effector cells in cardiac fibrosis, improves diabetes-induced HFpEF and elucidates the underlying mechanisms. Twenty-week-old db/db mice exhibited HFpEF, as confirmed by echocardiography and hemodynamic measurements. Proteomics was performed on CFs isolated from the hearts of 20-week-old C57BL/6 and db/db mice. Bioinformatic prediction was used to identify target proteins. Experimental validation was performed in both high glucose (HG)-treated neonatal mouse CFs (NMCFs) and diabetic hearts. TAX1 binding protein 1 (TAX1BP1) was identified as the most significantly differentially expressed protein between 20-week-old C57BL/6 and db/db mice. TAX1BP1 mRNA and protein were markedly downregulated in CFs from diabetic hearts and HG-cultured NMCFs. Overexpression of TAX1BP1 profoundly inhibited HG/diabetes-induced NF-κB nuclear translocation and collagen synthesis in CFs, improved cardiac fibrosis, hypertrophy, inflammation and HFpEF in diabetic mice. Mechanistically, signal transducer and activator of transcription 3 (STAT3), which is phosphorylated and translocated from the cytoplasm into the nucleus under hyperglycemic conditions, bound to TAX1BP1 promoter and blocked TAX1BP1 transcriptional activity, consequently promoting NF-κB nuclear translocation and collagen synthesis in CFs, aggravating cardiac fibrosis, hypertrophy and inflammation, leading to HFpEF in db/db mice. Taken together, our findings demonstrate that targeting regulation of STAT3-TAX1BP1-NF-κB signaling in CFs may be a promising therapeutic approach for diabetes-induced HFpEF.


Assuntos
Cardiomiopatias , Diabetes Mellitus Experimental , Insuficiência Cardíaca , Animais , Humanos , Camundongos , Cardiomiopatias/metabolismo , Colágeno/metabolismo , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/metabolismo , Regulação para Baixo , Fibroblastos/metabolismo , Fibrose , Insuficiência Cardíaca/metabolismo , Hipertrofia/metabolismo , Inflamação/metabolismo , Camundongos Endogâmicos C57BL , Proteínas de Neoplasias/genética , NF-kappa B/metabolismo , Fator de Transcrição STAT3/metabolismo , Volume Sistólico
13.
Small ; : e2310306, 2023 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-38143297

RESUMO

Bismuth sulfide is a promising thermoelectric material because of its low cost and toxicity; however, its low electrical conductivity limits its thermoelectric properties. In this study, Bi2 S3 +x wt% HfCl4 (x = 0, 0.25, 0.5, 0.75, and 1.0) bulk samples are fabricated using a combination of melting and spark plasma sintering. The microstructures, electronic structures, and thermoelectric properties of the composites are characterized. The results of electronic structure calculations show that doping with HfCl4 produces an impurity energy level that narrows the bandgap and allows the Fermi energy level to enter the conduction band, leading to a favorable increase in carrier concentration. By regulating the HfCl4 doping concentration, the electrical conductivity of the 0.75 wt% doped sample reaches 253 Scm-1 at 423 K and its maximum ZT value is 0.47 at 673 K. Moreover, the sample is compounded with Bi2 S3 nanorods prepared by the hydrothermal method, reducing thermal conductivity by 30% due to the introduction of additional interfaces and pores. This resulted in a final ZT value of 0.61 at 673 K, which is approximately eight times higher than that of pure Bi2 S3 . This step-by-step optimization approach provides a valuable methodology for enhancing the performance of other thermoelectric material systems.

14.
J Am Chem Soc ; 2023 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-37922502

RESUMO

The room-temperature thermoelectric performance of materials underpins their thermoelectric cooling ability. Carrier mobility plays a significant role in the electronic transport property of materials, especially near room temperature, which can be optimized by proper composition control and growing crystals. Here, we grow Pb-compensated AgPb18+xSbTe20 crystals using a vertical Bridgman method. A large weighted mobility of ∼410 cm2 V-1 s-1 is achieved in the AgPb18.4SbTe20 crystal, which is almost 4 times higher than that of the polycrystalline counterpart due to the elimination of grain boundaries and Ag-rich dislocations verified by atom probe tomography, highlighting the significant benefit of growing crystals for low-temperature thermoelectrics. Due to the largely promoted weighted mobility, we achieve a high power factor of ∼37.8 µW cm-1 K-2 and a large figure of merit ZT of ∼0.6 in AgPb18.4SbTe20 crystal at 303 K. We further designed a 7-pair thermoelectric module using this n-type crystal and a commercial p-type (Bi, Sb)2Te3-based material. As a result, a high cooling temperature difference (ΔT) of ∼42.7 K and a power generation efficiency of ∼3.7% are achieved, revealing promising thermoelectric applications for PbTe-based materials near room temperature.

15.
ACS Appl Mater Interfaces ; 15(48): 55903-55915, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-37996252

RESUMO

Selective hydrogenation of α,ß-unsaturated aldehydes into unsaturated alcohols is a process in high demand in organic synthesis, pharmaceuticals, and food production. This process requires the precise hydrogenation of C═O bonds, a challenge that requires a tailored catalyst. Single-atom alloys (SAAs), where individual atoms of one metal are distributed in a host metal matrix, offer a potential solution to this challenge. Nevertheless, identifying the appropriate SAA capable of targeted adsorption and the efficient activation of C═O bonds remains a substantial hurdle. In this work, we synergistically combine density functional theory (DFT) calculations, active learning, and microkinetic simulations to design SAAs for the efficient and selective hydrogenation of α,ß-unsaturated aldehydes. We first comprehensively assessed the potential of 66 SAAs across 264 surfaces (including (100), (110), (111), and (320) crystal planes), to gauge their potential in activating C═C and C═O bonds. Our assessment unveiled the excellent selectivity of the Ti1Au SAA in activating C═O bonds. Moreover, our detailed DFT calculations further demonstrated the high catalytic activity of Ti1Au(320) and Ti1Au(111) surfaces with a low activation energy barrier of only 0.60 eV. Subsequently, we conducted microkinetic simulations on the selective hydrogenation process of crotonaldehyde, by selecting Ti1Au (320) and (111) surfaces as the catalysts and demonstrated that they exhibited a remarkable selectivity and nearly 100% conversion toward crotyl alcohol in the temperature range from 373 to 553 K. The present study not only reveals novel SAAs for targeted hydrogenation of α,ß-unsaturated aldehydes but also establishes a promising path toward efficient design of selective hydrogenation catalysts more broadly.

16.
Adv Sci (Weinh) ; 10(33): e2301639, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37870182

RESUMO

Stem cells play critical roles in cell therapies and tissue engineering for nerve repair. However, achieving effective delivery of high cell density remains a challenge. Here, a novel cell delivery platform termed the hyper expansion scaffold (HES) is developed to enable high cell loading. HES facilitated self-promoted and efficient cell absorption via a dual driving force model. In vitro tests revealed that the HES rapidly expanded 80-fold in size upon absorbing 2.6 million human amniotic epithelial stem cells (hAESCs) within 2 min, representing over a 400% increase in loading capacity versus controls. This enhanced uptake benefited from macroscopic swelling forces as well as microscale capillary action. In spinal cord injury (SCI) rats, HES-hAESCs promoted functional recovery and axonal projection by reducing neuroinflammation and improving the neurotrophic microenvironment surrounding the lesions. In summary, the dual driving forces model provides a new rationale for engineering hydrogel scaffolds to facilitate self-promoted cell absorption. The HES platform demonstrates great potential as a powerful and efficient vehicle for delivering high densities of hAESCs to promote clinical treatment and repair of SCI.


Assuntos
Traumatismos da Medula Espinal , Regeneração da Medula Espinal , Ratos , Animais , Humanos , Tecidos Suporte , Traumatismos da Medula Espinal/terapia , Engenharia Tecidual , Impressão Tridimensional
17.
Artigo em Inglês | MEDLINE | ID: mdl-37903333

RESUMO

Many cathode materials store zinc ions based on the intercalation reaction mechanism in neutral aqueous Zn-ion batteries, and the structural design of the cathodes has been stuck in the curing mode by extending the ion diffusion channel. Here, we first develop halide ions to unlock the electrochemical activity of conversion-type Bi2O3 in aqueous Zn-ion batteries. Notably, the iodide ion shows the best performance compatibility with the Bi2O3 cathode. The electrochemical reaction mechanism studies show that iodide ions can be regarded as a redox medium to reduce the charge-transfer activation energy and motivate the conversion of Bi2O3 from Bi3+ to Bi0 during the cycle. Unsurprising, the discharge-specific capacity can reach 436.8 mAh g-1 at 0.5 A g-1 and achieve a cyclic lifespan of 6000 cycles at a current density of 3 A g-1. The activation of the Bi2O3 conversion reaction by iodide ions is of great significance for broadening the research range of ZIB cathode materials.

18.
AsiaIntervention ; 9(2): 114-123, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37736199

RESUMO

Background: A novel quantitative flow ratio (µQFR) for bifurcated coronary vessels, derived from a single projection, has been recently reported. Provisional stenting is effective for most bifurcation lesions. However, the clinical value of the side branch (SB) µQFR in patients with coronary bifurcation lesions undergoing provisional stenting remains unclear. Aims: This study aims to determine the clinical predictive value of the SB µQFR after provisional stenting in patients with coronary bifurcation lesions. Methods: Between June 2015 and May 2018, 288 patients with true coronary bifurcation lesions who underwent a provisional approach without SB treatment (including predilation, kissing balloon inflation or stenting) were classified by an SB µQFR <0.8 (n=65) and ≥0.8 (n=223) groups. The primary endpoint was the three-year composite of target vessel failure (TVF), including cardiac death, target vessel myocardial infarction (TVMI), and revascularisation (TVR). Results: Three years after the procedures, there were 43 (14.9%) TVFs, with 19 (29.2%) in the SB µQFR <0.8 and 24 (10.8%) in the SB µQFR ≥0.8 groups (adjusted hazard ratio [HR] 2.45, 95% confidence interval [CI] 1.39-5.54; p=0.003), mainly driven by increased TVMI (16.9% vs 5.4%, adjusted HR 3.29, 95% CI: 1.15-6.09; p=0.030) and TVR (15.4% vs 2.2%, adjusted HR 6.39, 95% CI: 2.04-13.48; p=0.007). Baseline diameter stenosis at the ostial SB and SB lesion length were the two predictors of an SB µQFR <0.8 immediately after stenting the main vessel, whereas previous percutaneous coronary intervention and an SB µQFR <0.8 were the two independent factors of 3-year TVF. Conclusions: An SB µQFR <0.8 immediately after the provisional approach is strongly associated with clinical events. Further randomised studies with large patient populations are warranted.

19.
Circ Res ; 133(6): 508-531, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37589160

RESUMO

BACKGROUND: Hypoxia is a major cause and promoter of pulmonary hypertension (PH), a representative vascular remodeling disease with poor prognosis and high mortality. However, the mechanism underlying how pulmonary arterial system responds to hypoxic stress during PH remains unclear. Endothelial mitochondria are considered signaling organelles on oxygen tension. Results from previous clinical research and our studies suggested a potential role of posttranslational SUMOylation (small ubiquitin-like modifier modification) in endothelial mitochondria in hypoxia-related vasculopathy. METHODS: Chronic hypoxia mouse model and Sugen/hypoxia rat model were employed as PH animal models. Mitochondrial morphology and subcellular structure were determined by transmission electron and immunofluorescent microscopies. Mitochondrial metabolism was determined by mitochondrial oxygen consumption rate and extracellular acidification rate. SUMOylation and protein interaction were determined by immunoprecipitation. RESULTS: The involvement of SENP1 (sentrin-specific protease 1)-mediated SUMOylation in mitochondrial remodeling in the pulmonary endothelium was identified in clinical specimens of hypoxia-related PH and was verified in human pulmonary artery endothelial cells under hypoxia. Further analyses in clinical specimens, hypoxic rat and mouse PH models, and human pulmonary artery endothelial cells and human embryonic stem cell-derived endothelial cells revealed that short-term hypoxia-induced SENP1 translocation to endothelial mitochondria to regulate deSUMOylation (the reversible process of SUMOylation) of mitochondrial fission protein FIS1 (mitochondrial fission 1), which facilitated FIS1 assembling with fusion protein MFN2 (mitofusin 2) and mitochondrial gatekeeper VDAC1 (voltage-dependent anion channel 1), and the membrane tethering activity of MFN2 by enhancing its oligomerization. Consequently, FIS1 deSUMOylation maintained the mitochondrial integrity and endoplasmic reticulum-mitochondria calcium communication across mitochondrial-associated membranes, subsequently preserving pulmonary endothelial function and vascular homeostasis. In contrast, prolonged hypoxia disabled the FIS1 deSUMOylation by diminishing the availability of SENP1 in mitochondria via inducing miR (micro RNA)-138 and consequently resulted in mitochondrial dysfunction and metabolic reprogramming in pulmonary endothelium. Functionally, introduction of viral-packaged deSUMOylated FIS1 within pulmonary endothelium in mice improved pulmonary endothelial dysfunction and hypoxic PH development, while knock-in of SUMO (small ubiquitin-like modifier)-conjugated FIS1 in mice exaggerated the diseased cellular and tissue phenotypes. CONCLUSIONS: By maintaining endothelial mitochondrial homeostasis, deSUMOylation of FIS1 adaptively preserves pulmonary endothelial function against hypoxic stress and consequently protects against PH. The FIS1 deSUMOylation-SUMOylation transition in pulmonary endothelium is an intrinsic pathogenesis of hypoxic PH.


Assuntos
Hipertensão Pulmonar , Doenças Vasculares , Humanos , Camundongos , Ratos , Animais , Hipertensão Pulmonar/etiologia , Hipertensão Pulmonar/prevenção & controle , Células Endoteliais , Mitocôndrias , Modelos Animais de Doenças , Endotélio , Ubiquitinas , Proteínas de Membrana , Proteínas Mitocondriais
20.
Chirality ; 35(12): 983-992, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37464916

RESUMO

Fluoxetine (FLT) is a widely used antidepressant in clinical practice, which can be metabolized into active norfluoxetine (NFLT) in vivo. The stereoselectivity of FLT and NFLT enantiomers across the blood-brain barrier (BBB) is still to be clarified. In this study, accurate and reliable UPLC-MS/MS enantioselective analysis was established in rat plasma and brain. The characteristics of FLT and NFLT enantiomers across the BBB were studied by chemical knockout of rat transporters. We found that the dominant enantiomers of FLT and NFLT were S-FLT and R-NFLT, respectively, both in plasma and in brain. The FLT and NFLT enantiomers showed significant stereoselectivity across the BBB, and S-FLT and S-NFLT were the dominant configurations across the BBB. Chemical knockout of organic cation transporter 1 (OCT1) and OCT3 can affect the ratio of plasma FLT and NFLT enantiomers into the brain, suggesting that OCT1/3 is stereoselective for FLT and NFLT transport across the BBB.


Assuntos
Fluoxetina , Transportador 1 de Cátions Orgânicos , Ratos , Animais , Fluoxetina/análise , Fluoxetina/metabolismo , Transportador 1 de Cátions Orgânicos/metabolismo , Barreira Hematoencefálica , Cromatografia Líquida/métodos , Estereoisomerismo , Espectrometria de Massas em Tandem/métodos
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