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ConspectusThe hydrogenative conversion of both CO and CO2 into high-value multicarbon (C2+) compounds, such as olefins, aromatic hydrocarbons, ethanol, and liquid fuels, has attracted much recent attention. The hydrogenation of CO is related to the chemical utilization of various carbon resources including shale gas, biomass, coal, and carbon-containing wastes via syngas (a mixture of H2 and CO), while the hydrogenation of CO2 by green H2 to chemicals and liquid fuels would contribute to recycling CO2 for carbon neutrality. The state-of-the-art technologies for the hydrogenation of CO/CO2 to C2+ compounds primarily rely on a direct route via Fischer-Tropsch (FT) synthesis and an indirect route via two methanol-mediated processes, i.e., methanol synthesis from CO/CO2 and methanol to C2+ compounds. The direct route would be more energy- and cost-efficient owing to the reduced operation units, but the product selectivity of the direct route via FT synthesis is limited by the Anderson-Schulz-Flory (ASF) distribution. Selectivity control for the direct hydrogenation of CO/CO2 to a high-value C2+ compound is one of the most challenging goals in the field of C1 chemistry, i.e., chemistry for the transformation of one-carbon (C1) molecules.We have developed a relay-catalysis strategy to solve the selectivity challenge arising from the complicated reaction network in the hydrogenation of CO/CO2 to C2+ compounds involving multiple intermediates and reaction channels, which inevitably lead to side reactions and byproducts over a conventional heterogeneous catalyst. The core of relay catalysis is to design a single tandem-reaction channel, which can direct the reaction to the target product controllably, by choosing appropriate intermediates (or intermediate products) and reaction steps connecting these intermediates, and arranging optimized yet matched catalysts to implement these steps like a relay. This Account showcases representative relay-catalysis systems developed by our group in the past decade for the synthesis of liquid fuels, lower (C2-C4) olefins, aromatics, and C2+ oxygenates from CO/CO2 with selectivity breaking the limitation of conventional catalysts. These relay systems are typically composed of a metal or metal oxide for CO/CO2/H2 activation and a zeolite for C-C coupling or reconstruction, as well as a third or even a fourth catalyst component with other functions if necessary. The mechanisms for the activation of H2 and CO/CO2 on metal oxides, which are distinct from that on the conventional transition or noble metal surfaces, are discussed with emphasis on the role of oxygen vacancies. Zeolites catalyze the conversion of intermediates (including hydrocracking/isomerization of heavier hydrocarbons, methanol-to-hydrocarbon reactions, and carbonylation of methanol/dimethyl ether) in the relay system, and the selectivity is mainly controlled by the Brønsted acidity and the shape-selectivity or the confinement effect of zeolites. We demonstrate that the thermodynamic/kinetic matching of the relay steps, the proximity and spatial arrangement of the catalyst components, and the transportation of intermediates/products in sequence are the key issues guiding the selection of each catalyst component and the construction of an efficient relay-catalysis system. Our methodology would also be useful for the transformation of other C1 molecules via controlled C-C coupling, inspiring more efforts toward precision catalysis.
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BACKGROUND: Dual antiplatelet therapy (DAPT) with aspirin as a background therapy has become the standard care after percutaneous coronary intervention. However, some adverse noncardiac effects limited the use of aspirin in clinical practice. Thus, evaluation of pharmacological alternatives to aspirin is attractive. Previous data indicated that indobufen could lessen the unwanted side effects of aspirin while retaining the antithrombotic efficacy, but its combination with a P2Y12 inhibitor still lacks randomized clinical trial evidence. METHODS: In this randomized, open-label, noninferiority trial, patients with negative cardiac troponin undergoing coronary drug-eluting stent implantation were randomly assigned in a 1:1 ratio to receive either indobufen-based DAPT (indobufen 100 mg twice a day plus clopidogrel 75 mg/d for 12 months) or conventional DAPT (aspirin 100 mg/d plus clopidogrel 75 mg/d for 12 months). The primary end point was a 1-year composite of cardiovascular death, nonfatal myocardial infarction, ischemic stroke, definite or probable stent thrombosis, or Bleeding Academic Research Consortium criteria type 2, 3, or 5 bleeding. The end points were adjudicated by an independent Clinical Event Committee. RESULTS: Between January 11, 2018, and October 12, 2020, 4551 patients were randomized in 103 cardiovascular centers: 2258 patients to the indobufen-based DAPT group and 2293 to the conventional DAPT group. The primary end point occurred in 101 patients (4.47%) in the indobufen-based DAPT group and 140 patients (6.11%) in the conventional DAPT group (absolute difference, -1.63%; Pnoninferiority<0.001; hazard ratio, 0.73 [95% CI, 0.56-0.94]; P=0.015). Cardiovascular death, nonfatal myocardial infarction, ischemic stroke, and stent thrombosis were observed in 0.13%, 0.40%, 0.80%, and 0.22% of patients in the indobufen-based DAPT group and 0.17%, 0.44%, 0.83%, and 0.17% of patients in the conventional DAPT group (all P>0.05). The occurrence of Bleeding Academic Research Consortium criteria type 2, 3, or 5 bleeding events was lower in the indobufen-based DAPT group compared with the conventional DAPT group (2.97% versus 4.71%; hazard ratio, 0.63 [95% CI, 0.46-0.85]; P=0.002), with the main decrease in type 2 bleeding (1.68% versus 3.49%; hazard ratio, 0.48 [95% CI, 0.33-0.70]; P<0.001). CONCLUSIONS: In Chinese patients with negative cardiac troponin undergoing drug-eluting stent implantation, indobufen plus clopidogrel DAPT compared with aspirin plus clopidogrel DAPT significantly reduced the risk of 1-year net clinical outcomes, which was driven mainly by a reduction in bleeding events without an increase in ischemic events. REGISTRATION: URL: https://www.chictr.org.cn; Unique identifier: ChiCTR-IIR-17013505.
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Stents Farmacológicos , Infarto do Miocárdio , Humanos , Aspirina/uso terapêutico , Clopidogrel/uso terapêutico , Quimioterapia Combinada , Stents Farmacológicos/efeitos adversos , Hemorragia/etiologia , AVC Isquêmico/etiologia , Infarto do Miocárdio/tratamento farmacológico , Intervenção Coronária Percutânea/efeitos adversos , Inibidores da Agregação Plaquetária/uso terapêutico , Trombose/etiologia , Resultado do Tratamento , TroponinaRESUMO
Composite oxides have been widely applied in the hydrogenation of CO/CO2 to methanol or as the component of bifunctional oxide-zeolite for the synthesis of hydrocarbon chemicals. However, it is still challenging to disentangle the stepwise formation mechanism of CH3OH at working conditions and selectively convert CO2 to hydrocarbon chemicals with narrow distribution. Here, we investigate the reaction network of the hydrogenation of CO2 to methanol over a series of spinel oxides (AB2O4), among which the Zn-based nanostructures offer superior performance in methanol synthesis. Through a series of (quasi) in situ spectroscopic characterizations, we evidence that the dissociation of H2 tends to follow a heterolytic pathway and that hydrogenation ability can be regulated by the combination of Zn with Ga or Al. The coordinatively unsaturated metal sites over ZnAl2Ox and ZnGa2Ox originating from oxygen vacancies (OVs) are evidenced to be responsible for the dissociative adsorption and activation of CO2. The evolution of the reaction intermediates, including both carbonaceous and hydrogen species at high temperatures and pressures over the spinel oxides, has been experimentally elaborated at the atomic level. With the integration of a series of zeolites or zeotypes, high selectivities of hydrocarbon chemicals with narrow distributions can be directly produced from CO2 and H2, offering a promising route for CO2 utilization.
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Intervertebral disc degeneration (IVDD) is a common chronic orthopaedic disease in orthopaedics that imposes a heavy economic burden on people and society. Although it is well established that IVDD is associated with genetic susceptibility, ageing and obesity, its pathogenesis remains incompletely understood. Previously, IVDD was thought to occur because of excessive mechanical loading leading to destruction of nucleus pulposus cells (NPCs), but studies have shown that IVDD is a much more complex process associated with inflammation, metabolic factors and NPCs death and can involve all parts of the disc, characterized by causing NPCs death and extracellular matrix (ECM) degradation. The damage pattern of NPCs in IVDD is like that of some programmed cell death, suggesting that IVDD is associated with programmed cell death. Although apoptosis and pyroptosis of NPCs have been studied in IVDD, the pathogenesis of intervertebral disc degeneration can still not be fully elucidated by using only traditional cell death modalities. With increasing research, some new modes of cell death, PANoptosis, ferroptosis and senescence have been found to be closely related to intervertebral disc degeneration. Among these, PANoptosis combines essential elements of pyroptosis, apoptosis and necroptosis to form a highly coordinated and dynamically balanced programmed inflammatory cell death process. Furthermore, we believe that PANoptosis may also crosstalk with pyroptosis and senescence. Therefore, we review the progress of research on multiple deaths of NPCs in IVDD to provide guidance for clinical treatment.
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Metal-organic framework (MOF)-based mixed-matrix membranes (MMMs) represent a class of composite membranes that seamlessly integrate the properties of MOF fillers and polymer matrix into a hybrid system and have been widely used in countless advanced technologies. However, there remains a need for scalable and simple manufacturing techniques that can fabricate a MOF-based MMM with uniform dispersion. Herein, a series of MMMs with well-dispersed MOFs are constructed by a soft spray technique. In brief, by uniformly spraying metal ions onto the surface of a mixed solution containing polyvinylpyrrolidone (PVP) and organic ligands, a free-standing MMM is synthesized at the miscible liquid-liquid interface, facilitated by the dual function of metal ions. Moreover, soft spray technology can also introduce multifunctional materials into the MMM to customize performance. We have successfully introduced carbon black into a MOF-based MMM by soft spray, resulting in MMMs with excellent photothermal effects. The resulted MOF-based MMM exhibits favorable catalytic performance in the condensation reaction of benzaldehyde with primary amines, and the MOF-based MMM modified with carbon black significantly boosts the endothermic CO2 conversion. The work opens a new avenue for the development of MOF-based MMMs with a promising future.
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OBJECTIVES: This study evaluated the long-term efficacy and safety of radiofrequency ablation (RFA) for intrathoracic goiter (ITG) over a follow-up period exceeding six months. METHODS: From 2017 to 2022, 22 patients (6 males, 16 females) with 24 ITGs treated with RFA at a single medical center were evaluated. All patients underwent ultrasonography (US), computed tomography (CT), or magnetic resonance imaging (MRI) before RFA. Follow-up CT/MRI was performed six months after the initial RFA and then every 6-12 months. The primary outcomes measured were the degree of extension, goiter volume, volume reduction rate (VRR), tracheal deviation, and tracheal lumen. Additionally, we assessed the outcomes of single-session RFA (n = 16) vs. multiple sessions (n = 8) on goiters and explored the correlation between ITG volume measurements obtained using ultrasonography and CT/MRI. RESULTS: The median follow-up period was 12 months (interquartile range: 6-36.8 months). At the last follow-up, the nodule volume measured by CT/MRI had significantly decreased (76.2 vs. 24.6 mL; p < 0.05), with a VRR of 64.6%. Patients who underwent multiple RFA sessions showed a significantly higher VRR than the single-session patients (63.8 vs. 80.1%, p < 0.05). The intraclass correlation between goiter volumes measured using US and CT/MRI was moderate. CONCLUSION: This study affirms the long-term efficacy and safety of RFA for ITG, providing an alternative treatment for nonsurgical candidates. Multiple RFA sessions may be beneficial for achieving better volume reduction. Sole reliance on ultrasonography is inadequate; therefore, integrating CT/MRI is essential for accurate pre-RFA and follow-up assessments.
Intrathoracic goiters significantly impact both cosmetic appearance and induce numerous compressive symptoms.Radiofrequency ablation brought notable volume reduction and persistent, effective alleviation of compressive symptoms.Radiofrequency ablation presents a promising therapeutic modality with long-term benefits for patients with intrathoracic goiter.
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Imageamento por Ressonância Magnética , Ablação por Radiofrequência , Tomografia Computadorizada por Raios X , Ultrassonografia , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Ablação por Radiofrequência/métodos , Imageamento por Ressonância Magnética/métodos , Tomografia Computadorizada por Raios X/métodos , Idoso , Ultrassonografia/métodos , Adulto , Resultado do Tratamento , Bócio Subesternal/diagnóstico por imagem , Bócio Subesternal/cirurgiaRESUMO
Near-infrared light sources have potential applications in many fields. Cr3+ is a good luminescence centre to prepare near-infrared phosphors. Improving the performance of existing near-infrared luminescent materials has indeed attracted great interest from researchers. The luminescence properties of Zn2TiO4:Cr3+ were improved by crystal field engineering strategies. Zn2+-Ti4+ was partially replaced using a Li+-Nb5+ ion pair based on the Zn2TiO4:Cr3+ phosphors. Luminescence Cr3+-activated luminescent materials are sensitive to changes in the local crystal structure and crystal field environment. Doping of Li+-Nb5+ increased the luminescence intensity up to 2.7 times that of the undoped sample. Also, the thermal stability of the phosphor was greatly increased by the replacement of Li+-Nb5+.
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Raios Infravermelhos , Luminescência , Íons , Lítio , ZincoRESUMO
Selective oxidation of methane to methanol by dioxygen (O2) is an appealing route for upgrading abundant methane resource and represents one of the most challenging reactions in chemistry due to the overwhelmingly higher reactivity of the product (methanol) versus the reactant (methane). Here, we report that gold nanoparticles dispersed on mordenite efficiently catalyze the selective oxidation of methane to methanol by molecular oxygen in aqueous medium in the presence of carbon monoxide. The methanol productivity reaches 1300 µmol gcat-1 h-1 or 280 mmol gAu-1 h-1 with 75% selectivity at 150 °C, outperforming most catalysts reported under comparable conditions. Both hydroxyl radicals and hydroperoxide species participate in the activation and conversion of methane, while it is shown that the lower affinity of methanol on gold mainly accounts for higher methanol selectivity.
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The ascending arousal system plays a crucial role in individuals' consciousness. Recently, advanced functional magnetic resonance imaging (fMRI) has made it possible to investigate the ascending arousal network (AAN) in vivo. However, the role of AAN in the neuropathology of human insomnia remains unclear. Our study aimed to explore alterations in AAN and its connections with cortical networks in chronic insomnia disorder (CID). Resting-state fMRI data were acquired from 60 patients with CID and 60 good sleeper controls (GSCs). Changes in the brain's functional connectivity (FC) between the AAN and eight cortical networks were detected in patients with CID and GSCs. Multivariate pattern analysis (MVPA) was employed to differentiate CID patients from GSCs and predict clinical symptoms in patients with CID. Finally, these MVPA findings were further verified using an external data set (32 patients with CID and 33 GSCs). Compared to GSCs, patients with CID exhibited increased FC within the AAN, as well as increased FC between the AAN and default mode, cerebellar, sensorimotor, and dorsal attention networks. These AAN-related FC patterns and the MVPA classification model could be used to differentiate CID patients from GSCs with 88% accuracy in the first cohort and 77% accuracy in the validation cohort. Moreover, the MVPA prediction models could separately predict insomnia (data set 1, R2 = .34; data set 2, R2 = .15) and anxiety symptoms (data set 1, R2 = .35; data set 2, R2 = .34) in the two independent cohorts of patients. Our findings indicated that AAN contributed to the neurobiological mechanism of insomnia and highlighted that fMRI-based markers and machine learning techniques might facilitate the evaluation of insomnia and its comorbid mental symptoms.
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Distúrbios do Início e da Manutenção do Sono , Humanos , Distúrbios do Início e da Manutenção do Sono/diagnóstico por imagem , Mapeamento Encefálico/métodos , Estado de Consciência , Cerebelo , Imageamento por Ressonância Magnética/métodos , Nível de Alerta , Encéfalo/diagnóstico por imagemRESUMO
Metal-zeolite composites with metal (oxide) and acid sites are promising catalysts for integrating multiple reactions in tandem to produce a wide variety of wanted products without separating or purifying the intermediates. However, the conventional design of such materials often leads to uncontrolled and non-ideal spatial distributions of the metal inside/on the zeolites, limiting their catalytic performance. Here we demonstrate a simple strategy for synthesizing double-shelled, contiguous metal oxide@zeolite hollow spheres (denoted as MO@ZEO DSHSs) with controllable structural parameters and chemical compositions. This involves the self-assembly of zeolite nanocrystals onto the surface of metal ion-containing carbon spheres followed by calcination and zeolite growth steps. The step-by-step formation mechanism of the material is revealed using mainly in situ Raman spectroscopy and X-ray diffraction and ex situ electron microscopy. We demonstrate that it is due to this structure that an Fe2O3@H-ZSM-5 DSHSs-showcase catalyst exhibits superior performance compared with various conventionally structured Fe2O3-H-ZSM-5 catalysts in gasoline production by the Fischer-Tropsch synthesis. This work is expected to advance the rational synthesis and research of hierarchically hollow, core-shell, multifunctional catalyst materials.
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BACKGROUND: Zika virus (ZIKV) infection is clinically known to induce testicular swelling, termed orchitis, and potentially impact male sterility, but the underlying mechanisms remain unclear. Previous reports suggested that C-type lectins play important roles in mediating virus-induced inflammatory reactions and pathogenesis. We thus investigated whether C-type lectins modulate ZIKV-induced testicular damage. METHODS: C-type lectin domain family 5 member A (CLEC5A) knockout mice were generated in a STAT1-deficient immunocompromised background (denoted clec5a-/-stat1-/-) to enable testing of the role played by CLEC5A after ZIKV infection in a mosquito-to-mouse disease model. Following ZIKV infection, mice were subjected to an array of analyses to evaluate testicular damage, including ZIKV infectivity and neutrophil infiltration estimation via quantitative RT-PCR or histology and immunohistochemistry, inflammatory cytokine and testosterone detection, and spermatozoon counting. Furthermore, DNAX-activating proteins for 12 kDa (DAP12) knockout mice (dap12-/-stat1-/-) were generated and used to evaluate ZIKV infectivity, inflammation, and spermatozoa function in order to investigate the potential mechanisms engaged by CLEC5A. RESULTS: Compared to experiments conducted in ZIKV-infected stat1-/- mice, infected clec5a-/-stat1-/- mice showed reductions in testicular ZIKV titer, local inflammation and apoptosis in testis and epididymis, neutrophil invasion, and sperm count and motility. CLEC5A, a myeloid pattern recognition receptor, therefore appears involved in the pathogenesis of ZIKV-induced orchitis and oligospermia. Furthermore, DAP12 expression was found to be decreased in the testis and epididymis tissues of clec5a-/-stat1-/- mice. As for CLEC5A deficient mice, ZIKV-infected DAP12-deficient mice also showed reductions in testicular ZIKV titer and local inflammation, as well as improved spermatozoa function, as compared to controls. CLEC5A-associated DAP12 signaling appears to in part regulate ZIKV-induced testicular damage. CONCLUSIONS: Our analyses reveal a critical role for CLEC5A in ZIKV-induced proinflammatory responses, as CLEC5A enables leukocytes to infiltrate past the blood-testis barrier and induce testicular and epididymal tissue damage. CLEC5A is thus a potential therapeutic target for the prevention of injuries to male reproductive organs in ZIKV patients.
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Orquite , Infecção por Zika virus , Zika virus , Humanos , Masculino , Camundongos , Animais , Sêmen/metabolismo , Camundongos Knockout , Inflamação/genética , Lectinas Tipo C/genética , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismoRESUMO
OBJECTIVE: Intervertebral disc degeneration (IVDD) is a chronic degenerative orthopedic illness that causes lower back pain as a typical clinical symptom, severely reducing patients' quality of life and work efficiency, and imposing a significant economic burden on society. IVDD is defined by rapid extracellular matrix breakdown, nucleus pulposus cell loss, and an inflammatory response. It is intimately related to the malfunction or loss of myeloid cells among them. Many mechanisms have been implicated in the development of IVDD, including inflammatory factors, oxidative stress, apoptosis, cellular autophagy, and mitochondrial dysfunction. In recent years, mitochondrial dysfunction has become a hot research topic in age-related diseases. As the main source of adenosine triphosphate (ATP) in myeloid cells, mitochondria are essential for maintaining myeloid cell survival and physiological functions. METHODS: We searched the PUBMED database with the search term "intervertebral disc degeneration and mitochondrial dysfunction" and obtained 82 articles, and after reading the abstracts and eliminating 30 irrelevant articles, we finally obtained 52 usable articles. RESULTS: Through a review of the literature, it was discovered that IVDD and cellular mitochondrial dysfunction are also linked. Mitochondrial dysfunction contributes to the advancement of IVDD by influencing a number of pathophysiologic processes such as mitochondrial fission/fusion, mitochondrial autophagy, cellular senescence, and cell death. CONCLUSION: We examine the molecular mechanisms of IVDD-associated mitochondrial dysfunction and present novel directions for quality management of mitochondrial dysfunction as a treatment approach to IVDD.
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Degeneração do Disco Intervertebral , Núcleo Pulposo , Humanos , Degeneração do Disco Intervertebral/metabolismo , Qualidade de Vida , Estresse Oxidativo , Mitocôndrias/metabolismo , Núcleo Pulposo/metabolismoRESUMO
A novel far-red emitting phosphor Sr2 MgWO6 : Mn4+ was fabricated using high-temperature solid-state reaction. X-ray diffraction patterns, scanning electron microscopy images, and photoluminescence excitation and photoluminescence spectra for this phosphor were analyzed in detail. The analysis revealed that its emission ranged from 600 to 800 nm and peaked at 699 nm, which was attributed to the 2 Eg â4 A2g transition of Mn4+ under 314 nm excitation. Moreover, we introduced rare-earth Yb3+ ions into the Sr2 MgWO6 :Mn4+ to improve its far-red emitting intensity. The photoluminescence (PL) intensity of the Yb3+ co-doped phosphor was three times higher than that of the single-doped phosphor. Therefore charge compensation is an efficient approach to improving PL intensity. The phosphor emitted a far-red light that resembled the pigments essential for plant growth in terms of the absorption spectrum. Therefore, the obtained phosphor, Sr2 MgWO6 :0.006Mn4+ ,0.2Yb3+ , had the potential to be a new type of far-red luminescent powder for indoor plant growth LEDs.
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Luz , Luminescência , EurópioRESUMO
Exhaustion of chimeric antigen receptor (CAR) T cells is one of the limitations for CAR T efficacy in solid tumors and for tumor recurrence after initial CAR T treatment. Tumor treatment with a combination of programmed cell death receptor-1 (PD-1)/programmed cell death ligand-1 (PD-L1) blockage and CD28-based CAR T cells has been intensively studied. However, it remains largely unclear whether autocrine single-chain variable fragments (scFv) PD-L1 antibody can improve 4-1BB-based CAR T cell anti-tumor activity and revert CAR T cell exhaustion. Here, we studied T cells engineered with autocrine PD-L1 scFv and 4-1BB-containing CAR. The antitumor activity and exhaustion of CAR T cells were investigated in vitro and in a xenograft cancer model using NCG mice. CAR T cells with autocrine PD-L1 scFv antibody demonstrate enhanced anti-tumor activity in solid tumors and hematologic malignancies by blocking the PD-1/PD-L1 signaling. Importantly, we found that CAR T exhaustion was largely diminished by autocrine PD-L1 scFv antibody in vivo. As such, 4-1BB CAR T with autocrine PD-L1 scFv antibody combined the power of CAR T cells and the immune checkpoint inhibitor, thereby increasing the anti-tumor immune function and CAR T persistence, providing a cell therapy solution for a better clinical outcome.
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Receptores de Antígenos Quiméricos , Anticorpos de Cadeia Única , Humanos , Animais , Camundongos , Receptores de Antígenos de Linfócitos T/metabolismo , Antígeno B7-H1/metabolismo , Receptor de Morte Celular Programada 1/metabolismo , Linhagem Celular Tumoral , Recidiva Local de Neoplasia/metabolismo , Linfócitos T , ImunidadeRESUMO
High-altitude cerebral edema (HACE), a potentially lethal disease, is associated with a time-dependent exposure to altitude-related hypobaric hypoxia (HH) and has reportedly been associated with microglia hyperactivation. Catechins are substances with good antioxidant properties, among which (-)-epigallocatechin gallate (EGCG) may play a neuroprotective role through the inhibition of microglia overactivation; however, the function of its analog- (-)-epicatechin gallate (ECG)-requires further elucidation. The aim of the present study was to investigate whether ECG prevented HACE by inhibiting HH-activated microglia. Primary microglia exposed to lipopolysaccharide (LPS)/ATP were co-treated with EGCG, ECG, and (-)-epigallocatechin, and ECG and EGCG exerted significant anti-inflammatory and neuroprotective effects. ECG inhibited the NF-κB pathway to prevent the activation of microglia induced by 1% O2. In addition, ECG ameliorated the increase in brain water content and aquaporin 4 expression induced by HH in mice. ECG also reduced the number of Iba1+ microglia in the brain, the release of proinflammatory factors, and the recruitment of microglia to blood vessels in HH-exposed mice. The outcomes of the present study revealed that ECG alleviated hypoxic hyperactivated microglia, reduced the neuroinflammation and blood-brain barrier permeability, and prevented HACE by inhibiting NF-κB signaling.
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Doença da Altitude , Edema Encefálico , Fármacos Neuroprotetores , Trifosfato de Adenosina/metabolismo , Doença da Altitude/complicações , Doença da Altitude/metabolismo , Animais , Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Aquaporina 4/metabolismo , Aquaporina 4/farmacologia , Edema Encefálico/complicações , Edema Encefálico/tratamento farmacológico , Edema Encefálico/prevenção & controle , Catequina/análogos & derivados , Hipóxia/complicações , Hipóxia/metabolismo , Lipopolissacarídeos/farmacologia , Camundongos , Microglia/metabolismo , NF-kappa B/metabolismo , Fármacos Neuroprotetores/metabolismo , Água/metabolismoRESUMO
BACKGROUND: High-altitude cerebral edema (HACE) is a serious and potentially fatal brain injury that is caused by acute hypobaric hypoxia (HH) exposure. Vasogenic edema is the main pathological factor of this condition. Hypoxia-induced disruptions of tight junctions in the endothelium trigger bloodâbrain barrier (BBB) damage and induce vasogenic edema. Nuclear respiratory factor 1 (NRF1) acts as a major regulator of hypoxia-induced endothelial cell injury, and caveolin-1 (CAV-1) is upregulated as its downstream gene in hypoxic endothelial cells. This study aimed to investigate whether CAV-1 is involved in HACE progression and the underlying mechanism. METHODS: C57BL/6 mice were exposed to HH (7600 m above sea level) for 24 h, and BBB injury was assessed by brain water content, Evans blue staining and FITC-dextran leakage. Immunofluorescence, transmission electron microscope, transendothelial electrical resistance (TEER), transcytosis assays, and western blotting were performed to confirm the role and underlying mechanism of CAV-1 in the disruption of tight junctions and BBB permeability. Mice or bEnd.3 cells were pretreated with MßCD, a specific blocker of CAV-1, and the effect of CAV-1 on claudin-5 internalization under hypoxic conditions was detected by immunofluorescence, western blotting, and TEER. The expression of NRF1 was knocked down, and the regulation of CAV-1 by NRF1 under hypoxic conditions was examined by qPCR, western blotting, and immunofluorescence. RESULTS: The BBB was severely damaged and was accompanied by a significant loss of vascular tight junction proteins in HACE mice. CAV-1 was significantly upregulated in endothelial cells, and claudin-5 explicitly colocalized with CAV-1. During the in vitro experiments, hypoxia increased cell permeability, CAV-1 expression, and claudin-5 internalization and downregulated tight junction proteins. Simultaneously, hypoxia induced the upregulation of CAV-1 by activating NRF1. Blocking CAV-1-mediated intracellular transport improved the integrity of TJs in hypoxic endothelial cells and effectively inhibited the increase in BBB permeability and brain water content in HH animals. CONCLUSIONS: Hypoxia upregulated CAV-1 transcription via the activation of NRF1 in endothelial cells, thus inducing the internalization and autophagic degradation of claudin-5. These effects lead to the destruction of the BBB and trigger HACE. Therefore, CAV-1 may be a potential therapeutic target for HACE. Video abstract.
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Edema Encefálico , Caveolina 1 , Hipóxia , Animais , Camundongos , Altitude , Barreira Hematoencefálica , Edema Encefálico/complicações , Edema Encefálico/metabolismo , Caveolina 1/metabolismo , Claudina-5/metabolismo , Células Endoteliais/metabolismo , Hipóxia/complicações , Hipóxia/metabolismo , Camundongos Endogâmicos C57BL , Fator 1 Nuclear Respiratório/metabolismo , Proteínas de Junções Íntimas/metabolismo , Junções Íntimas/metabolismoRESUMO
INTRODUCTION: Radiofrequency ablation (RFA) is recognized as an effective technique for the treatment of benign thyroid nodules (BTNs), although the long-term results are limited. This study aimed to evaluate the residual vital volume increase, regrowth, and new growth over a 2-year period after RFA among different nodule volume groups. SUBJECTS AND METHODS: This retrospective study evaluated 135 patients with 153 BTNs who underwent ultrasound guided RFA. The BTNs were categorized into small (<10 mL), medium (10-30 mL), and large (>30 mL) according to the initial volume of BTNs prior to ablation. The volume changes of each nodule were analyzed at 1, 3, 6, 12 and 24 months after RFA. New growth was defined as the growth in volume not found in the early follow-up on ultrasonography. RESULTS: The initial ablation ratio of all BTNs was 99.67%. The mean volume reduction ratio (VRR) of BTNs was 85.53% after 2-year follow-up. The small nodule group showed a lower VRR compared to the other two groups at the 1-month follow-up, and there was no difference of VRR at the subsequent follow-ups. The incidence of residual vital volume increase was 4.58%. The overall incidence of regrowth was 3.92% and the mean timing of regrowth was 16.71 months. New growth occurred in 18.95% of patients. No further treatment was required in the majority of cases. CONCLUSION: RFA achieved a clinically relevant volume reduction in different sizes of single BTNs which persisted for at least 2 years, thereby preventing the need for retreatment.
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Ablação por Radiofrequência , Nódulo da Glândula Tireoide , Progressão da Doença , Seguimentos , Humanos , Ablação por Radiofrequência/métodos , Estudos Retrospectivos , Nódulo da Glândula Tireoide/diagnóstico por imagem , Nódulo da Glândula Tireoide/cirurgia , Resultado do TratamentoRESUMO
INTRODUCTION: This study aimed to investigate and compare the therapeutic efficacy and safety of ultrasound-guided radiofrequency ablation (RFA), between primary hyperparathyroidism (PHPT) and secondary hyperparathyroidism (SHPT) patients, with or without previous parathyroidectomy (PTX). SUBJECTS AND METHODS: A total of 21 patients (7 PHPT, 14 SHPT) underwent RFA for hyperparathyroidism (HPT) at Kaohsiung Chang Gung Memorial Hospital, Taiwan. Five of the 14 SHPT patients had previously received PTX. The laboratory data, volume change of each parathyroid nodule, symptomatic scores, and complications were analyzed and compared between all groups at 1 and 7 days, and at 1, 3, 6, and 12 months after RFA. RESULTS: After RFA, the volume reduction ratio (VRR) for all patients at the last follow-up was 93.76%, and clinical symptoms significantly improved. At 12 months, all PHPT patients achieved successful treatment of intact PTH (iPTH). In SHPT patients, the mean iPTH value significantly decreased 1-day post-RFA, subsequently exhibiting a transient rebound which proceeded to decrease, with 57.1% reaching successful treatment standards. SHPT patients with PTX showed a lower complication score, shorter ablation time, higher iPTH baseline and outcomes, and lower VRR, compared to patients without PTX. The serum calcium level significantly decreased to normal range in 85.7% of all patients at 12 months. Severe hypocalcemia occurred in 23.8% at 1 week, and all were corrected with calcium supplements. CONCLUSIONS: RFA demonstrates a therapeutic efficacy similar to PTX. It can thus be considered an effective alternative treatment for PHPT, SHPT, or post-PTX patients who are unsuitable for another PTX.
Assuntos
Hiperparatireoidismo Secundário , Ablação por Radiofrequência , Cálcio , Humanos , Hiperparatireoidismo Secundário/cirurgia , Hormônio Paratireóideo , Paratireoidectomia/efeitos adversos , Ablação por Radiofrequência/efeitos adversos , Estudos RetrospectivosRESUMO
Mature lysostaphin (mLst) is a glycineglycine endopeptidase, capable of specifically cleaving penta-glycine crosslinker in the peptidoglycan of Staphylococcus aureus cell wall. It is a very effective therapeutic enzyme to kill the multidrug-resistant S. aureus often encountered in hospital acquired infections. Fusing cellulose binding domain (CBD) to mLst significantly reduced the insoluble expression of mLst in E. coli. Employing mLst-cleavable peptides as fusion linkers leaded to an effective self-cleavage expression that CBD and mLst could be completely cleaved off from the fusions during the expression process. The presence of residue linker fragment at N-terminus of the cleaved-off mLst strongly inhibited the cell lytic activity of the recovered recombinant mLst, and only ~ 50% of the wild-type mLst activity could be retained. Intact CBD-Lst fusions were obtained when uncleavable peptide linkers were employed. With CBD at N-terminus of mLst, the intact fusion completely lost its cell lytic activity but the dipeptidase activity still remained. In contrast, approximately 10% cell lytic activity of mLst still could be maintained for the fusion with CBD at C-terminus of mLst. KEY POINTS: ⢠CBD fusion enhanced soluble expression of recombinant lysostaphin. ⢠In vivo self-cleavage of fusion linkers by the expressed lysostaphin fusions. ⢠Self-cleaved lysostaphin fusions retain most of dipeptidase but lose 50% cell lytic activity.
Assuntos
Dipeptidases , Staphylococcus aureus Resistente à Meticilina , Celulose , Escherichia coli/genética , Escherichia coli/metabolismo , Lisostafina/farmacologia , Tipagem de Sequências Multilocus , Peptidoglicano/metabolismoRESUMO
KEY MESSAGE: An ammonium transporter LbAMT3-1 overexpression increases the arbuscular abundance of mycorrhizal that opens the possibility of using LbAMT3-1 in breeding programs to improve symbiotic nutrient uptake in Lycium barbarum. Nitrogen (N) is one of the most essential nutrients required by plants and limits net primary production much of the time in most terrestrial ecosystems. Arbuscular mycorrhizal (AM) fungi can enhance plant nutrient uptake and improve plant productivity in nutrient limit ecosystems. Here, we identified an ammonia transporter, LbAMT3-1, specifically induced by AM fungi in Lycium barbarum. To understand the expression characteristics and biological functions, LbAMT3-1 was cloned, characterized, and overexpressed in Nicotiana tabacum (tobacco). A BLAST search identified the coding sequence for LbAMT3-1 with an open-reading frame of 1473 bp. Reverse transcription polymerase chain reaction (RT-PCR) analysis indicated that, besides mycorrhizal roots, LbAMT3-1 were barely detectable in other tissues, including stems and leaves. Promoter-GUS assay showed that GUS staining was detected in mycorrhizal roots, and GUS activity driven by the LbAMT3-1 promoter was exclusively confined to root cells containing arbuscules. LbAMT3-1 functionally complemented the yeast mutant efficiently, and yeast expressing LbAMT3-1 showed well growth on the agar medium with 0.02, 0.2, and 2 mM NH4+ supply. Moreover, overexpression of LbAMT3-1 in N. tabacum resulted a significant increase in arbuscular abundance and enhanced the nutrient acquisition capacity of mycorrhizal plants. Based on the results of our study, we propose that overexpression of LbAMT3-1 can promote P and N uptake of host plants through the mycorrhizal pathway, and increase the colonization intensity and arbuscular abundance, which opens the possibility of using LbAMT3-1 in breeding programs.