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1.
Nature ; 621(7978): 300-305, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37704763

RESUMO

Crystal phase is a key factor determining the properties, and hence functions, of two-dimensional transition-metal dichalcogenides (TMDs)1,2. The TMD materials, explored for diverse applications3-8, commonly serve as templates for constructing nanomaterials3,9 and supported metal catalysts4,6-8. However, how the TMD crystal phase affects the growth of the secondary material is poorly understood, although relevant, particularly for catalyst development. In the case of Pt nanoparticles on two-dimensional MoS2 nanosheets used as electrocatalysts for the hydrogen evolution reaction7, only about two thirds of Pt nanoparticles were epitaxially grown on the MoS2 template composed of the metallic/semimetallic 1T/1T' phase but with thermodynamically stable and poorly conducting 2H phase mixed in. Here we report the production of MoS2 nanosheets with high phase purity and show that the 2H-phase templates facilitate the epitaxial growth of Pt nanoparticles, whereas the 1T' phase supports single-atomically dispersed Pt (s-Pt) atoms with Pt loading up to 10 wt%. We find that the Pt atoms in this s-Pt/1T'-MoS2 system occupy three distinct sites, with density functional theory calculations indicating for Pt atoms located atop of Mo atoms a hydrogen adsorption free energy of close to zero. This probably contributes to efficient electrocatalytic H2 evolution in acidic media, where we measure for s-Pt/1T'-MoS2 a mass activity of 85 ± 23 A [Formula: see text] at the overpotential of -50 mV and a mass-normalized exchange current density of 127 A [Formula: see text] and we see stable performance in an H-type cell and prototype proton exchange membrane electrolyser operated at room temperature. Although phase stability limitations prevent operation at high temperatures, we anticipate that 1T'-TMDs will also be effective supports for other catalysts targeting other important reactions.

2.
Chem Rev ; 124(7): 4479-4539, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38552165

RESUMO

Crystal phase, a critical structural characteristic beyond the morphology, size, dimension, facet, etc., determines the physicochemical properties of nanomaterials. As a group of layered nanomaterials with polymorphs, transition metal dichalcogenides (TMDs) have attracted intensive research attention due to their phase-dependent properties. Therefore, great efforts have been devoted to the phase engineering of TMDs to synthesize TMDs with controlled phases, especially unconventional/metastable phases, for various applications in electronics, optoelectronics, catalysis, biomedicine, energy storage and conversion, and ferroelectrics. Considering the significant progress in the synthesis and applications of TMDs, we believe that a comprehensive review on the phase engineering of TMDs is critical to promote their fundamental studies and practical applications. This Review aims to provide a comprehensive introduction and discussion on the crystal structures, synthetic strategies, and phase-dependent properties and applications of TMDs. Finally, our perspectives on the challenges and opportunities in phase engineering of TMDs will also be discussed.

3.
Nat Mater ; 23(10): 1355-1362, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38589543

RESUMO

Unconventional 1T'-phase transition metal dichalcogenides (TMDs) have aroused tremendous research interest due to their unique phase-dependent physicochemical properties and applications. However, due to the metastable nature of 1T'-TMDs, the controlled synthesis of 1T'-TMD monolayers (MLs) with high phase purity and stability still remains a challenge. Here we report that 4H-Au nanowires (NWs), when used as templates, can induce the quasi-epitaxial growth of high-phase-purity and stable 1T'-TMD MLs, including WS2, WSe2, MoS2 and MoSe2, via a facile and rapid wet-chemical method. The as-synthesized 4H-Au@1T'-TMD core-shell NWs can be used for ultrasensitive surface-enhanced Raman scattering (SERS) detection. For instance, the 4H-Au@1T'-WS2 NWs have achieved attomole-level SERS detections of Rhodamine 6G and a variety of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike proteins. This work provides insights into the preparation of high-phase-purity and stable 1T'-TMD MLs on metal substrates or templates, showing great potential in various promising applications.

4.
Chem Rev ; 123(23): 13489-13692, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-37962496

RESUMO

As a key structural parameter, phase depicts the arrangement of atoms in materials. Normally, a nanomaterial exists in its thermodynamically stable crystal phase. With the development of nanotechnology, nanomaterials with unconventional crystal phases, which rarely exist in their bulk counterparts, or amorphous phase have been prepared using carefully controlled reaction conditions. Together these methods are beginning to enable phase engineering of nanomaterials (PEN), i.e., the synthesis of nanomaterials with unconventional phases and the transformation between different phases, to obtain desired properties and functions. This Review summarizes the research progress in the field of PEN. First, we present representative strategies for the direct synthesis of unconventional phases and modulation of phase transformation in diverse kinds of nanomaterials. We cover the synthesis of nanomaterials ranging from metal nanostructures such as Au, Ag, Cu, Pd, and Ru, and their alloys; metal oxides, borides, and carbides; to transition metal dichalcogenides (TMDs) and 2D layered materials. We review synthesis and growth methods ranging from wet-chemical reduction and seed-mediated epitaxial growth to chemical vapor deposition (CVD), high pressure phase transformation, and electron and ion-beam irradiation. After that, we summarize the significant influence of phase on the various properties of unconventional-phase nanomaterials. We also discuss the potential applications of the developed unconventional-phase nanomaterials in different areas including catalysis, electrochemical energy storage (batteries and supercapacitors), solar cells, optoelectronics, and sensing. Finally, we discuss existing challenges and future research directions in PEN.

5.
Nano Lett ; 2024 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-39494941

RESUMO

Phase engineering of two-dimensional (2D) transition metal dichalcogenides (TMDs) is an attractive avenue to construct new surface-enhanced Raman scattering (SERS) substrates. Herein, 2D WS2 and MoS2 monolayers with high-purity distorted octahedral phase (1T') are prepared for highly sensitive SERS detection of analytes (e.g., rhodamine 6G, rhodamine B and crystal violet). 1T'-WS2 and 1T'-MoS2 monolayers show the detection limits of 8.28 × 10-12 and 8.57 × 10-11 M for rhodamine 6G, with the enhancement factors of 4.6 × 108 and 3.9 × 107, respectively, which are comparable to noble-metal substrates, outperforming semiconducting 2H-W(Mo)S2 monolayers and most of the reported non-noble-metal substrates. First-principles density functional theory calculations show that their Raman enhancement effect is mainly ascribed to highly efficient interfacial charge transfer between the 1T'-W(Mo)S2 monolayers and analytes. Our study reveals that 2D TMDs with semimetallic 1T' phase are promising as next-generation SERS substrates.

6.
Gut ; 73(7): 1169-1182, 2024 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-38395437

RESUMO

OBJECTIVE: Hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC), mostly characterised by HBV integrations, is prevalent worldwide. Previous HBV studies mainly focused on a few hotspot integrations. However, the oncogenic role of the other HBV integrations remains unclear. This study aimed to elucidate HBV integration-induced tumourigenesis further. DESIGN: Here, we illuminated the genomic structures encompassing HBV integrations in 124 HCCs across ages using whole genome sequencing and Nanopore long reads. We classified a repertoire of integration patterns featured by complex genomic rearrangement. We also conducted a clustered regularly interspaced short palindromic repeat (CRISPR)-based gain-of-function genetic screen in mouse hepatocytes. We individually activated each candidate gene in the mouse model to uncover HBV integration-mediated oncogenic aberration that elicits tumourigenesis in mice. RESULTS: These HBV-mediated rearrangements are significantly enriched in a bridge-fusion-bridge pattern and interchromosomal translocations, and frequently led to a wide range of aberrations including driver copy number variations in chr 4q, 5p (TERT), 6q, 8p, 16q, 9p (CDKN2A/B), 17p (TP53) and 13q (RB1), and particularly, ultra-early amplifications in chr8q. Integrated HBV frequently contains complex structures correlated with the translocation distance. Paired breakpoints within each integration event usually exhibit different microhomology, likely mediated by different DNA repair mechanisms. HBV-mediated rearrangements significantly correlated with young age, higher HBV DNA level and TP53 mutations but were less prevalent in the patients subjected to prior antiviral therapies. Finally, we recapitulated the TONSL and TMEM65 amplification in chr8q led by HBV integration using CRISPR/Cas9 editing and demonstrated their tumourigenic potentials. CONCLUSION: HBV integrations extensively reshape genomic structures and promote hepatocarcinogenesis (graphical abstract), which may occur early in a patient's life.


Assuntos
Carcinoma Hepatocelular , Vírus da Hepatite B , Neoplasias Hepáticas , Integração Viral , Carcinoma Hepatocelular/virologia , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/virologia , Neoplasias Hepáticas/patologia , Vírus da Hepatite B/genética , Humanos , Integração Viral/genética , Animais , Camundongos , Masculino , Pessoa de Meia-Idade , Feminino , Adulto , Sequenciamento Completo do Genoma , Variações do Número de Cópias de DNA , Idoso
7.
J Cell Mol Med ; 28(7): e18242, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38509736

RESUMO

Articular cartilage defect is challenged by insufficient regenerative ability of cartilage. Catalpol (CA), the primary active component of Rehmanniae Radix, could exert protective effects against various diseases. However, the impact of CA on the treatment of articular cartilage injuries is still unclear. In this study, full-thickness articular cartilage defect was induced in a mouse model via surgery. The animals were intraperitoneally injected with CA for 4 or 8 weeks. According to the results of macroscopic observation, micro-computed tomography CT (µCT), histological and immunohistochemistry staining, CA treatment could promote mouse cartilage repair, resulting in cartilage regeneration, bone structure improvement and matrix anabolism. Specifically, an increase in the expression of CD90, the marker of mesenchymal stem cells (MSCs), in the cartilage was observed. In addition, we evaluated the migratory and chondrogenic effects of CA on MSCs. Different concentration of CA was added to C3H10 T1/2 cells. The results showed that CA enhanced cell migration and chondrogenesis without affecting proliferation. Collectively, our findings indicate that CA may be effective for the treatment of cartilage defects via stimulation of endogenous MSCs.


Assuntos
Doenças das Cartilagens , Cartilagem Articular , Glucosídeos Iridoides , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Animais , Camundongos , Cartilagem Articular/patologia , Microtomografia por Raio-X , Diferenciação Celular , Doenças das Cartilagens/metabolismo , Transplante de Células-Tronco Mesenquimais/métodos , Condrogênese
8.
J Am Chem Soc ; 146(34): 24141-24149, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39162360

RESUMO

Facet control and phase engineering of metal nanomaterials are both important strategies to regulate their physicochemical properties and improve their applications. However, it is still a challenge to tune the exposed facets of metal nanomaterials with unconventional crystal phases, hindering the exploration of the facet effects on their properties and functions. In this work, by using Pd nanoparticles with unconventional hexagonal close-packed (hcp, 2H type) phase, referred to as 2H-Pd, as seeds, a selective epitaxial growth method is developed to tune the predominant growth directions of secondary materials on 2H-Pd, forming Pd@NiRh nanoplates (NPLs) and nanorods (NRs) with 2H phase, referred to as 2H-Pd@2H-NiRh NPLs and NRs, respectively. The 2H-Pd@2H-NiRh NRs expose more (100)h and (101)h facets on the 2H-NiRh shells compared to the 2H-Pd@2H-NiRh NPLs. Impressively, when used as electrocatalysts toward hydrogen oxidation reaction (HOR), the 2H-Pd@2H-NiRh NRs show superior activity compared to the NiRh alloy with conventional face-centered cubic (fcc) phase (fcc-NiRh) and the 2H-Pd@2H-NiRh NPLs, revealing the crucial role of facet control in enhancing the catalytic performance of unconventional-phase metal nanomaterials. Density functional theory (DFT) calculations further unravel that the excellent HOR activity of 2H-Pd@2H-NiRh NRs can be attributed to the more exposed (100)h and (101)h facets on the 2H-NiRh shells, which possess high electron transfer efficiency, optimized H* binding energy, enhanced OH* binding energy, and a low energy barrier for the rate-determining step during the HOR process.

9.
BMC Microbiol ; 24(1): 283, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39085808

RESUMO

BACKGROUND: The guts of mammals are home to trillions of microbes, forming a complex and dynamic ecosystem. Gut microbiota is an important biological barrier for maintaining immune homeostasis. Recently, the use of antibiotics to clear gut microbiota has gained popularity as a low cost and easy-to-use alternative to germ-free animals. However, the effect of the duration of the antibiotic cocktail on the gut microbiome is unclear, and more importantly, the effect of dramatic changes in the gut microbiota on intestinal tissue morphology and local immune response is rarely reported. RESULTS: We observed a significant reduction in fecal microbiota species and abundance after 1 week of exposure to an antibiotic cocktail, gavage twice daily by intragastric administration. In terms of composition, Bacteroidetes and Firmicutes were replaced by Proteobacteria. Extending antibiotic exposure to 2-3 weeks did not significantly improve the overall efficiency of microbiotal consumption. No significant histomorphological changes were observed in the first 2 weeks of antibiotic cocktail exposure, but the expression of inflammatory mediators in intestinal tissue was increased after 3 weeks of antibiotic cocktail exposure. Mendelian randomization analysis showed that Actinobacteria had a significant causal association with the increase of IL-1ß (OR = 1.65, 95% CI = 1.23 to 2.21, P = 0.007) and TNF-α (OR = 1.81, 95% CI = 1.26 to 2.61, P = 0.001). CONCLUSIONS: Our data suggest that treatment with an antibiotic cocktail lasting 1 week is sufficient to induce a significant reduction in gut microbes. 3 weeks of antibiotic exposure can lead to the colonization of persistant microbiota and cause changes in intestinal tissue and local immune responses.


Assuntos
Antibacterianos , Fezes , Microbioma Gastrointestinal , Antibacterianos/farmacologia , Animais , Fezes/microbiologia , Microbioma Gastrointestinal/efeitos dos fármacos , Interleucina-1beta/genética , Camundongos , Bactérias/efeitos dos fármacos , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Camundongos Endogâmicos C57BL , Bacteroidetes/efeitos dos fármacos , Firmicutes/efeitos dos fármacos
10.
Stem Cells ; 41(5): 482-492, 2023 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-36702547

RESUMO

Osteoarthritis (OA) is an entire joint disease with pathological alteration in both articular cartilage and subchondral bone. It has been recognized recently the association between metabolic syndrome and OA, particularly glucose metabolism in regulation of articular cartilage homeostasis and joint integrity. Whereas the role of glucose metabolism in subchondral bone sclerosis remains largely unknown during pathogenesis of OA. Consistent with common OA features, we observed subchondral bone sclerosis and abnormal bone remodeling in human OA joints and murine OA joints as reflected by hyperactive bone resorption and overall bone formation which was measured via dynamic histomorphometry. Osx-CreER;tdTomato mice also displayed the similar overall bone formation under injury-induced OA condition. Immunohistochemistry further revealed increased IL-1ß expression in human and murine OA subchondral bone. Given the inflammatory environment in joints under OA condition, we treated MC3T3-E1 cell, a pre-osteoblast cell line, with IL-1ß in this study and demonstrated that IL-1ß treatment could stimulate the cell osteogenic differentiation and meanwhile upregulate glycolysis and oxidative phosphorylation in cell cultures. More importantly, intraperitoneal injection of 2-deoxy-D-glucose (2-DG) and oligomycin (OGM), respectively, suppressed the subchondral bone glycolysis and oxidative phosphorylation in mice. Consequently, 2-DG and OGM treatment attenuated abnormal osteoblast differentiation and protected against aberrant bone formation in subchondral bone and articular cartilage degradation in wildtype mice following with joint injury. Collectively, these data strongly suggest glycolysis and oxidative may serve as important therapeutic targets for OA treatment.


Assuntos
Cartilagem Articular , Osteoartrite , Humanos , Camundongos , Animais , Osteogênese , Esclerose/complicações , Esclerose/metabolismo , Esclerose/patologia , Osso e Ossos/metabolismo , Cartilagem Articular/patologia , Inflamação/patologia
11.
Chemistry ; 30(26): e202400278, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38406889

RESUMO

A novel [3+3] annulation reaction of 2-alkenylindoles with hydrazonyl chlorides in the presence of base for the formation of pyridazino[4,5-b]indoles was developed. This approach provided a convenient and efficient way to synthesize a series of functionalized pyridazino[4,5-b]indoles derivatives. The method exhibited a broad substrate scope and provided the corresponding pyridazino[4,5-b]indoles products with excellent yields.

12.
FASEB J ; 37(2): e22743, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36645109

RESUMO

Thrombospondin-2 (Tsp2), a glycoprotein in the extracellular matrix, plays a critical role in the maintenance of vascular homeostasis. However, its role in the pathogenesis of cardiovascular disorders such as intimal hyperplasia is not fully elucidated. This study, therefore, aims to explore the effect of Tsp2 on intimal hyperplasia and its associated underlying mechanisms. Intimal hyperplasia (IH) was established using a modified wire-mediated femoral artery injury model. Immunofluorescence and qPCR identified upregulated Tsp2 expression in the injured femoral artery compared with the uninjured femoral artery. Similarly, TSP2 expression was also increased in human samples from the atherosclerotic femoral artery and colocalized with vascular smooth muscle cells (VSMCs). Compared with the wild-type littermates, Tsp2 knockout mice displayed a mitigated IH in the injured femoral artery, as demonstrated by a decreased neointimal area and intimal/median ratio. Primary mouse VSMCs were cultured to explore the mechanism by which Tsp2 influenced IH in vitro. PDGF-stimulated VSMCs presented an elevated Tsp2 expression and enhanced migration and proliferation. However, Tsp2 knockdown by siRNA blocked the increased migration and proliferation of VSMCs. Further analysis identified an association between Notch3 and IH when the intracellular domain of Notch3 (Nicd3) was upregulated in PDGF-stimulated VSMCs and femoral arteries with IH in human tissues. Along with the overexpression and downregulation of Tsp2, the Nicd3 expression was also up and downregulated accordingly. Tsp2 was associated with IH and may serve as a therapeutic target for IH. Downregulation of Tsp2 could mitigate the progression of IH by modulating the proliferation and migration of VSMCs.


Assuntos
Músculo Liso Vascular , Neointima , Trombospondinas , Animais , Humanos , Camundongos , Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Células Cultivadas , Modelos Animais de Doenças , Hiperplasia/metabolismo , Camundongos Knockout , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Neointima/metabolismo , Trombospondinas/genética , Trombospondinas/metabolismo
13.
Artigo em Inglês | MEDLINE | ID: mdl-39242332

RESUMO

OBJECTIVES: Cognitive frailty refers to the co-occurrence of cognitive impairment and frailty without concurrent Alzheimer's disease or dementia. Studies of cognitive frailty and mortality have been limited to single country or older people. However, frailty and cognitive decline may occur much earlier. We aimed to examine the association between different cognitive frailty status and subsequent all-cause mortality among middle-aged and older people in 17 countries. METHODS: Participants aged 50 and over were drawn from six prospective cohorts of aging. We classified participants according to their cognitive impairment and frailty status into the following groups: none, only cognitive impairment, only frailty and cognitive frailty. Competing-risks regression models were used to evaluate the association of different cognitive frailty status at baseline with subsequent all-cause mortality. RESULTS: The cognitive frailty group had a higher mortality risk compared to those without cognitive impairment and frailty groups. Meta-analysis results showed participants with cognitive frailty (pooled subhazard ratio [SHR] = 2.34, 95% confidence interval [CI]: 2.01-2.72, I2 = 68.0%) had a higher mortality risk compared with those with only cognitive impairment status (pooled SHR = 1.36, 95% CI: 1.25-1.48, I2 = 3.0%) or only frailty status (pooled SHR = 1.83, 95% CI: 1.72-1.95, I2 = 31.0%). The association between cognitive frailty and mortality were stronger among those who were aged 70 years and older, males, single and nonconsumers of alcohol. CONCLUSIONS: Cognitive frailty, frailty or cognitive impairment alone, is associated with an increased risk of all-cause mortality in Asian, European and American countries. Physical and cognitive function screening should be conducted as early as possible in middle-aged and older people, and targeted intervention approaches should be developed to reduce the incidence of adverse health outcomes.

14.
J Endovasc Ther ; : 15266028241231036, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38357875

RESUMO

OBJECTIVE: The purpose of this study is to compare the initial outcomes of using the Chocolate balloon pre-dilatation (CLP) and sequential enlarging angioplasty pre-dilatation (sequential balloon pre-dilation [SP]) techniques versus the conventional balloon pre-dilatation (CP) method prior to drug-coated balloon (DCB) treatment for femoropopliteal (FP) lesions. METHODS: This was a retrospective analysis of prospectively collected data from the CIVILIAN (Clinical InVestigation of different lesIon preparation modaLIty followed by DCB in femoropopliteal Artery occlusioN disease) registry. Between March 2021 and November 2022, 3 pre-dilation techniques used prior to the DCB angioplasty were included. The study endpoint included intraoperative finial severe dissection after provisional stent placement, bailout stenting rate, the diameter of the largest pre-dilation balloon and DCB, as well as major adverse events (MAEs), including death, major limb amputation, or target vessel revascularization at 6 months. RESULTS: During the study period, 435 limbs (429 patients) were pre-dilated before DCB treatment in FP lesions, 166 limbs were pre-dilated with Chocolate balloons, 93 limbs with sequential enlarging balloon pre-dilation technique, and 176 limbs with CP. The largest pre-dilation balloon was significantly larger in CLP and SP groups than that in the CP group (CLP 4.74±0.52 mm vs CP 4.36±0.64 mm, p<0.001; SP 4.82±0.69 mm vs CP 4.36±0.63 mm, p<0.001). A consistent result was shown in DCB diameter (CLP 4.86±0.44 mm vs CP 4.71±0.51 mm, p=0.003; SP 4.90±0.58 mm vs CP 4.71±0.51 mm, p=0.006). The bailout stenting rate was significantly lower in the CLP group than that in the CP group (18.1% vs 30.1%, p=0.011). The rates of MAEs at 6 months in the CLP and SP groups were comparable to those in the CP group (7.2% and 8.6% vs 6.3%, p>0.05). The risk for intraoperative bailout stenting rate was related to TASC D classification (3.59, 95% CI: 1.83-7.05, p<0.001), chronic total occlusion (CTO) lesion (1.82, 95% CI: 1.07-3.10, p=0.028), as well as pre-dilated with the conventional balloon (1.64, 95% CI: 1.00-2.69, p=0.048). CONCLUSIONS: By utilizing chocolate balloon and sequential enlarging angioplasty, it becomes possible to use larger pre-dilation balloons and DCBs. In addition, the use of the chocolate balloon can significantly reduce the need for bailout stenting when compared with conventional balloons. CLINICAL IMPACT: The utilization of a chocolate balloon and sequential enlarging angioplasty has emerged as a promising technique for angioplasty procedures. This approach allows for the use of larger pre-dilation balloons and drug-coated balloons. The use of the chocolate balloon can significantly reduce the need for bail-out stenting when compared to conventional balloons. Further research is required to determine the impact of vessel preparation techniques on the primary patency.

15.
J Org Chem ; 89(10): 7339-7346, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38662477

RESUMO

NHC-catalyzed [4+2] annulation of 2H-azirine-2-carbaldehydes with ketimines and isocyanates has been developed, providing straightforward synthetic protocols for constructing structurally intriguing pyrimido[1,2-a]indolediones and pyrimidinediones under mild conditions with excellent yields. This protocol can be used to synthesize the core skeleton of pharmaceutically important drugs and pyrimido[1,2-a]indoledione-containing natural products, making it potentially valuable for creating biologically active derivatives.

16.
J Vasc Interv Radiol ; 35(2): 251-258, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37866474

RESUMO

PURPOSE: To report the outcomes of the IN-DEPT trial assessing the feasibility, preliminary safety data, and 12-month outcomes of a new drug-coated balloon (DCB) product for peripheral artery disease (PAD) in Chinese patients. MATERIALS AND METHODS: This is a prospective, multicenter, single-arm clinical trial. A total of 160 patients with superficial femoral artery (SFA) and/or proximal popliteal artery lesions were treated with a new paclitaxel-coated DCB. The preliminary effectiveness end point was 12-month primary patency. The primary safety end point was freedom from device- and procedure-related mortality over 30 days and freedom from major target limb amputation and clinically driven target lesion revascularization (CD-TLR) within 12 months after the index procedure. RESULTS: In total, 160 patients presented with 162 target lesions. A total of 139 lesions (85.8%) were treated with 1 DCB, whereas the other 23 lesions (14.2%) were treated with 2 devices. The device success rate was 100%. A total of 135 subjects reached the preliminary effectiveness end point, with a 12-month primary patency rate of 84.4%. There was no 30-day device- or procedure-related death or unplanned major target limb amputation at 12 months. Five CD-TLRs (3.1%) occurred during the 12-month follow-up period. CONCLUSIONS: Results from the IN-DEPT SFA trial showed satisfactory feasibility and safety of the new DCB over 12 months in Chinese patients with PAD and femoropopliteal de novo lesions, including both stenoses and total occlusions.


Assuntos
Angioplastia com Balão , Fármacos Cardiovasculares , Doença Arterial Periférica , Humanos , Artéria Femoral/diagnóstico por imagem , Artéria Femoral/patologia , Estudos Prospectivos , Angioplastia com Balão/efeitos adversos , Materiais Revestidos Biocompatíveis , Fatores de Tempo , Fármacos Cardiovasculares/efeitos adversos , Artéria Poplítea/diagnóstico por imagem , Doença Arterial Periférica/diagnóstico por imagem , Doença Arterial Periférica/terapia , Doença Arterial Periférica/patologia , Grau de Desobstrução Vascular , Resultado do Tratamento
17.
Analyst ; 149(20): 4981-4996, 2024 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-39311536

RESUMO

Glass nano/micron pipettes, owing to their easy preparation, unique confined space at the tip, and modifiable inner surface of the tip, can capture the ion current signal caused by a single entity, making them widely used in the construction of highly sensitive and highly selective electrochemical sensors for single entity analysis. Compared with other solid-state nanopores, their conical nano-tip causes less damage to cells when inserted into them, thereby becoming a powerful tool for the in situ analysis of important substances in cells. However, glass nanopipettes have some shortcomings, such as poor mechanical properties, difficulty in precise preparation (aperture less than 50 nm), and easy blockage during complex real sample detection, limiting their practicability. Therefore, in recent years, researchers have conducted a series of studies on glass micropipettes. Ionic current rectification technology is a novel electrochemical analysis technique. Compared with traditional electrochemical analysis methods, it does not generate redox products during the detection process; therefore, it can not only be used for the determination of non-electrochemically active substances, but also causes less damage to the cell/living body in situ analysis, becoming a powerful analysis technology for the in situ analysis of cells/in vivo in recent years. In this review, we summarize the preparation and functionalization of glass nano/micron pipettes and introduce the sensing mechanisms of two electrochemical sensing platforms constructed using glass nano/micron pipette-based ion current rectification sensing technology as well as their applications in single cell/in vivo analysis, existing problems, and future prospects.


Assuntos
Técnicas Eletroquímicas , Vidro , Análise de Célula Única , Análise de Célula Única/instrumentação , Análise de Célula Única/métodos , Vidro/química , Técnicas Eletroquímicas/instrumentação , Técnicas Eletroquímicas/métodos , Humanos , Animais , Íons/química , Íons/análise , Nanotecnologia/instrumentação , Nanotecnologia/métodos
18.
Thromb J ; 22(1): 48, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38844941

RESUMO

BACKGROUND: Risks of recurrence and major bleeding with extended anticoagulation in Asian patients with venous thromboembolism (VTE) are similar to those in non-Asian patients but risks according to baseline risk factor profiles is not well documented. METHODS: Subgroup analysis of two randomized trials, which compared once-daily rivaroxaban (20 mg or 10 mg) with placebo or aspirin (100 mg) for extended treatment in Asian patients with VTE who had completed 6-12 months of anticoagulation. Index events were classified as unprovoked, provoked by major persistent risk factors, minor persistent risk factors, minor transient risk factors, or major transient risk factors. One-year cumulative risks of recurrent VTE were calculated for these risk factor profiles. RESULTS: 367 patients received rivaroxaban, 159 aspirin, and 48 placebo. For patients with unprovoked VTE, one-year cumulative incidences of recurrence in the 202 patients given rivaroxaban, the 89 given aspirin and the 28 given placebo were 1.6%, 5.8%, and 14.8%, respectively. For patients with VTE provoked by minor persistent risk factors, these incidences were 0% in the 74 patients given rivaroxaban, 9.3% in the 36 given aspirin, and 0% in the 12 given placebo. No recurrent VTE occurred in patients with VTE provoked by major persistent or transient risk factors or minor transient risk factors. Rivaroxaban was not associated with a significant increase in major bleeding. CONCLUSIONS: Rivaroxaban seems to be an effective and safe option for extended treatment in Asian patients, especially those presenting with unprovoked VTE. Subgroups of patients with provoked risk factors were too small to draw meaningful conclusions. TRIAL REGISTRATION: NCT00439725 and NCT02064439.

19.
Environ Res ; 244: 117899, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38109953

RESUMO

Fluoride pollution in water has become a global challenge. This challenge especially affects China as a country experiencing serious fluoride pollution. While the have been past studies on the spatial distribution of fluoride, there has been less attention on different forms of fluoride. This study collected 176 samples (60, 40, and 76 ice, water, and sediment samples, respectively) from Lake Ulansuhai during the freezing period. The occurrence and spatial distribution characteristics of fluoride in lake ice-water-sediment were explored using Kriging interpolation, Piper three-line diagram, and Gibbs diagram analysis methods. The migration and transformation of fluoride during the freezing period were revealed and the factors influencing fluoride concentration in the water body were discussed considering the hydrochemical characteristics of lake surface water. The results showed that the average fluoride concentrations in the upper ice, middle ice and lower ice were 0.18, 0.09, and 0.12 mg/L, respectively, decreasing from north to south in the lake. The average concentrations of fluoride in surface water and bottom water were 0.63 and 0.83 mg/L, respectively. The concentrations of fluoride in ice and water were within the World Health Organisation drinking water threshold of 1.50 mg/L and the Class III Chinese surface water standard (GB3838-2002). The average sediment total fluorine was 1344.38 ± 200 mg/kg, significantly exceeding the global average (321 mg/kg) and decreasing with depth. The contents of water soluble, exchangeable, Fe/Mn bound, organic bound, and residual fluorides were 40.22-47.18, 13.24-43.23, 49.52-160.48, and 71.59-173.03 mg/kg, respectively. There was a significant positive correlation between fluoride concentration in ice and that in water. The change in fluoride concentration in water was mainly due to specific climatic and geographical conditions, pH, hydrochemical characteristics and ice sealing. This study is of great significance for the management of high-fluorine lakes in arid and semi-arid areas.


Assuntos
Fluoretos , Poluentes Químicos da Água , Gelo/análise , Lagos/química , Congelamento , Flúor/análise , Monitoramento Ambiental/métodos , Água/química , China , Poluentes Químicos da Água/análise
20.
Mol Cell Proteomics ; 21(3): 100193, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34999219

RESUMO

Protein post-translational modifications play key roles in multiple cellular processes by allowing rapid reprogramming of individual protein functions. Acylation, one of the most important post-translational modifications, is involved in different physiological activities including cell differentiation and energy metabolism. In recent years, the progression in technologies, especially the antibodies against acylation and the highly sensitive and effective mass spectrometry-based proteomics, as well as optimized functional studies, greatly deepen our understanding of protein acylation. In this review, we give a general overview of the 12 main protein acylations (formylation, acetylation, propionylation, butyrylation, malonylation, succinylation, glutarylation, palmitoylation, myristoylation, benzoylation, crotonylation, and 2-hydroxyisobutyrylation), including their substrates (histones and nonhistone proteins), regulatory enzymes (writers, readers, and erasers), biological functions (transcriptional regulation, metabolic regulation, subcellular targeting, protein-membrane interactions, protein stability, and folding), and related diseases (cancer, diabetes, heart disease, neurodegenerative disease, and viral infection), to present a complete picture of protein acylations and highlight their functional significance in future research.


Assuntos
Lisina , Doenças Neurodegenerativas , Acetilação , Acilação , Histonas/metabolismo , Humanos , Lisina/metabolismo , Processamento de Proteína Pós-Traducional
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