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1.
Artículo en Inglés | MEDLINE | ID: mdl-38695529

RESUMEN

Ionic conductive elastomers (ICEs) exhibit a compelling combination of ionic conductivity and elastic properties, rendering them excellent candidates for stretchable electronics, particularly in applications like sensing devices. Despite their appeal, a significant challenge lies in the reprocessing of ICEs without compromising their performance. To address this issue, we propose a strategy that leverages covalent adaptable networks (CANs) for the preparation of ICEs. Specifically, ß-amino ester bonds as dynamic motifs are incorporated into a poly(ethylene oxide) network containing lithium bis(trifluoromethane) sulfonimide (LiTFSI) salt. LiTFSI-containing ß-amino ester networks (LBAEs) exhibit superb transparency (94%), thermal stability (>280 °C), and modest conductivity (0.00576 mS·cm-1 at 20 °C), and some LBAEs maintain operational capability across a wide temperature range (-20 to 100 °C). By regulating the lithium salt content, the mechanical properties, conductivities, and viscoelastic behaviors can be tailored. Benefiting from these features, LBAEs have been successfully applied in sensing devices for monitoring human motion (e.g., finger bending, swallowing, and clenching). Notably, even after four reprocessing cycles, LBAEs demonstrate structural integrity and maintain their operational capability. This novel approach represents a promising solution to the reprocessing challenges associated with flexible conductive devices, demonstrating the successful integration of CANs and ICEs.

2.
Nat Commun ; 15(1): 3177, 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38609361

RESUMEN

Elemental Te is important for semiconductor applications including thermoelectric energy conversion. Introducing dopants such as As, Sb, and Bi has been proven critical for improving its thermoelectric performance. However, the remarkably low solubility of these elements in Te raises questions about the mechanism with which these dopants can improve the thermoelectric properties. Indeed, these dopants overwhelmingly form precipitates rather than dissolve in the Te lattice. To distinguish the role of doping and precipitation on the properties, we have developed a correlative method to locally determine the structure-property relationship for an individual matrix or precipitate. We reveal that the conspicuous enhancement of electrical conductivity and power factor of bulk Te stems from the dopant-induced metavalently bonded telluride precipitates. These precipitates form electrically beneficial interfaces with the Te matrix. A quantum-mechanical-derived map uncovers more candidates for advancing Te thermoelectrics. This unconventional doping scenario adds another recipe to the design options for thermoelectrics and opens interesting pathways for microstructure design.

3.
Sci Rep ; 14(1): 8450, 2024 04 11.
Artículo en Inglés | MEDLINE | ID: mdl-38600309

RESUMEN

The death of coronavirus disease 2019 (COVID-19) is primarily due to from critically ill patients, especially from ARDS complications caused by SARS-CoV-2. Therefore, it is essential to contribute an in-depth understanding of the pathogenesis of the disease and to identify biomarkers for predicting critically ill patients at the molecular level. Immunogenic cell death (ICD), as a specific variant of regulatory cell death driven by stress, can induce adaptive immune responses against cell death antigens in the host. Studies have confirmed that both innate and adaptive immune pathways are involved in the pathogenesis of SARS-CoV-2 infection. However, the role of ICD in the pathogenesis of severe COVID-19 has rarely been explored. In this study, we systematically evaluated the role of ICD-related genes in COVID-19. We conducted consensus clustering, immune infiltration analysis, and functional enrichment analysis based on ICD differentially expressed genes. The results showed that immune infiltration characteristics were altered in severe and non-severe COVID-19. In addition, we used multiple machine learning methods to screen for five risk genes (KLF5, NSUN7, APH1B, GRB10 and CD4), which are used to predict COVID-19 severity. Finally, we constructed a nomogram to predict the risk of severe COVID-19 based on the classification and recognition model, and validated the model with external data sets. This study provides a valuable direction for the exploration of the pathogenesis and progress of COVID-19, and helps in the early identification of severe cases of COVID-19 to reduce mortality.


Asunto(s)
COVID-19 , Humanos , COVID-19/genética , SARS-CoV-2/genética , Enfermedad Crítica , Muerte Celular Inmunogénica , Aprendizaje Automático
4.
Org Biomol Chem ; 22(16): 3245-3248, 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38567821

RESUMEN

Visible-light-promoted hydrocarboxylation of allenes with formate salt and CO2 was developed for the first time using commercially available [Ir(ppy)2(dtbbpy)]PF6 as a photocatalyst. This strategy provides an efficient and practical method to access ß,γ-unsaturated linear carboxylic acids in moderate yields with complete regioselectivity.

5.
Adv Sci (Weinh) ; : e2400377, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38561956

RESUMEN

Ligand-protected heterometallic nanoclusters in contrast to homo-metal counterparts show more broad applications due to the synergistic effect of hetero-metals but their controllable syntheses remain a challenge. Among heterometallic nanoclusters, monovalent Ag-Cu compounds are rarely explored due to much difference of Ag(I) and Cu(I) such as atom radius, coordination habits, and redox potential. Encouraged by copper-catalyzed alkyne-azide cycloaddition (CuAAC) reaction, comproportionation reaction of Cu(II)X2 and Cu(0) in the presence of (PhC≡CAg)n complex and molybdate generated a core-shell peanut-shaped 66-nuclear Ag(I)-Cu(I) heterometallic nanocluster, [(Mo4O16)2@Cu12Ag54(PhC≡C)50] (referred to as Ag54Cu12). The structure and composition of Ag-Cu heterometallic nanocluster are fully characterized. X-ray single crystal diffraction reveals that Ag54Cu12 has a peanut-shaped silver(I)/copper(I) heterometallic nanocage protected by fifty phenylacetylene ligands in µ3-modes and encapsulated two mutually twisted tetramolybdates. Heterometallic nanocage contains a 54-Ag-atom outer ellipsoid silver cage decorated by 12 copper inside wall. Nanosized Ag54Cu12 is a n-type narrow-band-gap semiconductor with a good photocurrent response. Preliminary experiments demonstrates that Ag54Cu12 itself and activated carbon supported Ag54Cu12/C are effective catalysts for 1,3-dipole cycloaddition between alkynes and azides at ambient conditions. The work provides not only a new synthetic route toward Ag(I)-Cu(I) nanoclusters but also an important heterometallic intermediate in CuAAC catalytic reaction.

6.
Mol Biol Rep ; 51(1): 74, 2024 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-38175266

RESUMEN

BACKGROUND: Mechanical Ventilation (MV) is an essential mechanism of life support in the clinic. It may also lead to ventilator-induced acute lung injury (VILI) due to local alveolar overstretching and/or repeated alveolar collapse. However, the pathogenesis of VILI is not completely understood, and its occurrence and development may be related to physiological processes such as the inflammatory response, oxidative stress, and apoptosis. Some studies have found that the the apelin/APJ axis is an endogenous antagonistic mechanism activated during acute respiratory distress syndrome(ARDS), that can counteract the injury response and prevent uncontrolled lung injury. To indicate that apelin-13 plays a protective role in VILI, an animal model of VILI was established in this study to explore whether apelin-13 can alleviate VILI in rats by inhibiting inflammation, apoptosis and oxidative stress. METHODS: SD rats were divided into four groups: control, high tidal volume, high tidal volume + normal saline and high tidal volume + apelin-13. After tracheotomy, the rats in control maintained spontaneous breathing, and the other rats were connected to the small animal ventilator for 4 h to establish the rat VILI model. The mRNA expression of apelin was measured by real-time quantitative polymerase chain reaction(qRT-PCR), immunofluorescence and Western blotting(WB) were used to detect the expression level of APJ, and WB was used to detect the expression of the apoptotic proteins Bax and bcl-2. The degree of lung injury was evaluated by pathological staining of lung tissue,W/D ratio, and BALF total protein concentration. The expression of inflammatory factors(IL-1ß, IL-6, TNF-α) in alveolar lavage fluid was measured using ELISA. The activities of MPO and cat and the content of MDA, an oxidative product, in lung tissue were measured to evaluate the degree of oxidative stress in the lung. RESULTS: After treatment with apelin-13, the apelin/APJ axis in the lung tissue of VILI model rats was activated, and the effect was further enhanced. The pathological damage of lung tissue was alleviated, the expression of the antiapoptotic protein Bcl-2 and the proapoptotic protein Bax was reversed, and the levels of the inflammatory cytokines IL-1ß, IL-6, TNF-α levels were all decreased. MPO activity and MDA content decreased, while CAT activity increased. CONCLUSION: The apelin/apj axis is activated in VILI. Overexpression of apelin-13 further plays a protective role in VILI, mainly by including reducing pathological damage, the inflammatory response, apoptosis and antioxidant stress in lung tissue, thus delaying the occurrence and development of VILI.


Asunto(s)
Lesión Pulmonar Aguda , Síndrome de Dificultad Respiratoria , Animales , Ratas , Ratas Sprague-Dawley , Apelina/farmacología , Interleucina-6 , Factor de Necrosis Tumoral alfa , Proteína X Asociada a bcl-2/genética , Ventiladores Mecánicos
7.
Angew Chem Int Ed Engl ; 63(7): e202318390, 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38117040

RESUMEN

Luban locks with mortise and tenon structure have structural diversity and architectural stability, and it is extremely challenging to synthesize Luban lock-like structures at the molecular level. In this work, we report the cocrystallization of two structurally related atom-precise fcc silver nanoclusters Ag110 (SPhF)48 (PPh3 )12 (Ag110 ) and Ag14 (µ6 -S)(SPhF)12 (PPh3 )8 (Ag14 ). It is worth noting that the Ag110 cluster is the first compound to simulate the complex Luban lock structure at the molecular level. Meanwhile, Ag110 is the largest known fcc-based silver nanocluster, so far, there is no precedent for fcc silver nanocluster with more than 100 silver atoms. DFT calculations show that Ag110 is a 58-electron superatom with an electronically closed shell1S2 1P6 1D10 2S2 1F14 2P6 1G18 . Ag110 ⋅Ag14 can rapidly catalyze the reduction of 4-nitrophenol within 4 minutes. In addition, Ag110 presents clear structural evidence to reveal the critical size and mechanism of the transformation of metal core from fcc stacking to quasi-spherical superatom. This research work provides an important structural model for studying the nucleation mechanism and structural assembly of silver nanoclusters.

8.
Dalton Trans ; 53(3): 1245-1252, 2024 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-38112081

RESUMEN

The electrocatalytic splitting of water to produce hydrogen is regarded as an efficient and promising strategy but is limited by its large overpotential; thus, a highly efficient electrocatalyst is urgently needed. Mixed metal doping is an important strategy in defect engineering because the heteroatoms can change the intrinsic structure to form defects by affecting the atomic coordination mode and adjusting the electronic structure, which is often accompanied by morphological changes. Herein, two-dimensional layered bimetallic Co-pydc containing axially coordinated water molecules was selected by producing surface defects through Fe doping in Co centers as bifunctional electrocatalysts for OER and HER. The optimized Co0.59Fe0.41-pydc possesses outstanding OER performance with the lowest overpotential of 262 mV to reach j = 10 mA cm-2, and Co0.75Fe0.25-pydc possesses superior HER performance with the lowest overpotential of 96 mV at j = 10 mA cm-2. Furthermore, the overall water splitting device assembled with Co0.59Fe0.41-pydc@NF//Co0.59Fe0.41-pydc@NF affords a current density of 10 mA cm-2 at only 1.687 V. This work emphasizes the surface defects formed by tuning the electronic structure of metal centres accompanied with morphological changes of bimetallic dopants for efficient overall water splitting.

9.
ACS Macro Lett ; 12(12): 1698-1704, 2023 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-38039381

RESUMEN

Shape memory polymers (SMPs) are a type of smart shape-shifting material that can respond to various stimuli. Their shape recovery pathway is determined by the internal stress stored in the temporary shapes. Thus, manipulating the internal stress is key to the potential applications of SMPs. This is commonly achieved by the types of deformation forces applied during the programming stage. In contrast, we present here a digital laser direct writing method to selectively induce thermal relaxation of internal stress stored in the two-dimensional (2D) shape of a thermoplastic SMP. The internal stress field, while invisible under natural light, can be visualized under polarized light. Consequently, the digital stress pattern can be used for anticounterfeiting. In addition, further uniform heating induces the release of the programmed internal stress within the 2D film. This triggers its transformation into a three-dimensional (3D) shape, enabling 4D printing. The simplicity and versatility of our approach in manipulating internal stress and shape-shifting make it attractive for potential applications.

10.
BMC Pulm Med ; 23(1): 428, 2023 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-37925442

RESUMEN

OBJECTIVE: The present study aimed to determine the effect and mechanical mechanism of spontaneous breathing during mechanical ventilation on oxygenation and lung injury using Beagles dogs mild or moderate acute respiratory distress syndrome (ARDS) model. METHODS: After inducing mild or moderate ARDS by infusion of oleic acid, Eighteen Beagles dogs were randomly split into Spontaneous breathing group (BIPAPSB, n = 6), and Complete muscle paralysis group (BIPAPPC, n = 6),Six Beagles without ventilator support comprised the control group. Both groups were ventilated for 8 h under BIPAP mode. High-pressure was titrated TV to 6 ml/kg. A multi-pair esophageal balloon electrode catheter was used to measure respiratory mechanics and electromyogram. End-expiratory lung volume (EELV), gas exchange and respiratory variables were recorded in the process of mechanical ventilation. The contents of Interleukin (IL)-6 and IL-8 in lung tissue were measure using qRT-PCR. Besides, lung injury score was calculated in the end of mechanical ventilation. RESULTS: Based on the comparable setting of ventilator, BIPAPSB group exhibited higher safety peak transpulmonary pressure, abdominal pressure, EELV and P/F(PaO2/FiO2) than BIPAPPC group, whereas mean transpulmonary pressure, the mRNA levels of the IL-6 and IL-8 in the lung tissues and lung injury score in BIPAPSB group were lower than those in BIPAPPC group. CONCLUSION: In mild to moderate ARDS animal models, during mechanical ventilation, SB may improve respiratory function and reduce ventilator-induced lung injury. The mechanism may be that spontaneous inspiration up-regulates peak transpulmonary pressure and EELV; Spontaneous expiration decreases mean transpulmonary pressure by up-regulating intra-abdominal pressure, thereby reducing stress and strain.


Asunto(s)
Síndrome de Dificultad Respiratoria , Lesión Pulmonar Inducida por Ventilación Mecánica , Animales , Perros , Interleucina-8 , Pulmón , Síndrome de Dificultad Respiratoria/terapia , Respiración Artificial , Respiración , Presión de las Vías Aéreas Positiva Contínua , Interleucina-6
11.
Adv Mater ; : e2306387, 2023 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-38018316

RESUMEN

The most critical challenge for the large-scale commercialization of proton exchange membrane fuel cells (PEMFCs), one of the primary hydrogen energy technologies, is to achieve decent output performance with low usage of platinum (Pt). Currently, the performance of PEMFCs is largely limited by two issues at the catalyst/ionomer interface, specifically, the poisoning of active sites of Pt by sulfonate groups and the extremely sluggish local oxygen transport toward Pt. In the past few years, emerging strategies are derived to tackle these interface problems through materials optimization and innovation. This perspective summarizes the latest advances in this regard, and in the meantime unveils the molecule-level mechanisms behind the materials modulation of interfacial structures. This paper starts with a brief introduction of processes and structures of catalyst/ionomer interfaces, which is followed by a detailed review of progresses in key materials toward interface optimization, including catalysts, ionomers, and additives, with particular emphasis on the role of materials structure in regulating the intermolecular interactions. Finally, the challenges for the application of the established materials and research directions to broaden the material library are highlighted.

12.
Front Immunol ; 14: 1249878, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37781385

RESUMEN

Background: Disseminated tuberculosis is an uncommon but devastating form of tuberculosis, possibly developing with the immune response of patients. COVID-19 infection may produce an immunosuppressive effect with possible implications for tuberculosis dissemination. Case presentation: A 17-year-old female patient with a history of tuberculous pleurisy presented to the hospital with a high fever and life-threatening dyspnea after contracting a COVID-19 infection. Her condition deteriorated rapidly with grand mal epilepsy and acute gastrointestinal bleeding with a grossly depressed CD4 T-cell count, which was indicative of her profoundly immunosuppressed state. After identifying Mycobacterium tuberculosis in her cerebrospinal fluid and a subcutaneous abscess in her left lower back, she was diagnosed with disseminated tuberculosis involving both lungs, the central nervous system, the terminal ileum, the liver, bilateral adnexal tissue, and subcutaneous soft tissue in accordance with the chest and abdominal CT. Empirical treatment was initiated with dexamethasone (5 mg/day) and an anti-tuberculosis regimen of isoniazid, rifampicin, pyrazinamide, amikacin, and meropenem, which was replaced with faropenem after she left the hospital. The therapeutic effect was considered satisfied in the second month of follow-up. Conclusion: To the best of our knowledge, we report the first case report of disseminated tuberculosis after COVID-19 infection. Tuberculosis may disseminate and progress during the COVID-19 pandemic, requiring more significant studies to provide better diagnosis and treatment options for the co-infection.


Asunto(s)
COVID-19 , Mycobacterium tuberculosis , Tuberculosis Pleural , Humanos , Niño , Femenino , Adolescente , Pandemias , Isoniazida/uso terapéutico
13.
J Am Chem Soc ; 145(41): 22577-22583, 2023 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-37812140

RESUMEN

Atoms in special lattice sites can play a crucial role in realizing materials properties, which is long pursued but difficult to control. Herein, by adopting a stereochemically active lone-pair-containing metal substitution strategy, a nonlinear-optical (NLO) silicate crystal Li3(OH)PbSiO4 was successfully synthesized, featuring [PbSiO4]∞ layers with the perfect orientation of the stereochemically active lone-pair Pb(II) cation in the polar-axis lattice. Li3(OH)PbSiO4 overcomes the long-standing problem of silicates, that is, poor nonlinear properties because it exhibits both the largest birefringence of 0.082 and the largest phase-matchable second-harmonic-generation (SHG) efficiency of 21 × KDP among the known silicates. The successful polar-axis lattice substitution could offer a new direction for realizing the rational control of materials structures and properties.

14.
J Funct Biomater ; 14(9)2023 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-37754870

RESUMEN

Manganese (Mn) is an essential micronutrient in various physiological processes, but its functions in bone metabolism remain undefined. This is partly due to the interplay between immune and bone cells because Mn plays a central role in the immune system. In this study, we utilized the plasma immersion ion implantation and deposition (PIII&D) technique to introduce Mn onto the titanium surface. The results demonstrated that Mn-implanted surfaces stimulated the shift of macrophages toward the M1 phenotype and had minimal effects on the osteogenic differentiation of mouse bone marrow mesenchymal stem cells (mBMSCs) under mono-culture conditions. However, they promoted the M2 polarization of macrophages and improved the osteogenic activities of mBMSCs under co-culture conditions, indicating the importance of the crosstalk between mBMSCs and macrophages mediated by Mn in osteogenic activities. This study provides a positive incentive for the application of Mn in the field of osteoimmunology.

15.
Angew Chem Int Ed Engl ; 62(46): e202306896, 2023 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-37747767

RESUMEN

Developing efficient and robust hydrogen evolution reaction (HER) catalysts for scalable and sustainable hydrogen production through electrochemical water splitting is strategic and challenging. Herein, heterogeneous Mo8 O26 -NbNx Oy supported on N-doped graphene (defined as Mo8 O26 -NbNx Oy /NG) is synthesized by controllable hydrothermal reaction and nitridation process. The O-exposed Mo8 O26 clusters covalently confined on NbNx Oy nanodomains provide a distinctive interface configuration and appropriate electronic structure, where fully exposed multiple active sites give excellent HER performance beyond commercial Pt/C catalyst in pH-universal electrolytes. Theoretical studies reveal that the Mo8 O26 -NbNx Oy interface with electronic reconstruction affords near-optimal hydrogen adsorption energy and enhanced initial H2 O adsorption. Furthermore, the terminal O atoms in Mo8 O26 clusters cooperate with Nb atoms to promote the initial H2 O adsorption, and subsequently reduce the H2 O dissociation energy, accelerating the entire HER kinetics.

16.
Elife ; 122023 09 20.
Artículo en Inglés | MEDLINE | ID: mdl-37728612

RESUMEN

Billions of apoptotic cells are removed daily in a human adult by professional phagocytes (e.g. macrophages) and neighboring nonprofessional phagocytes (e.g. stromal cells). Despite being a type of professional phagocyte, neutrophils are thought to be excluded from apoptotic sites to avoid tissue inflammation. Here, we report a fundamental and unexpected role of neutrophils as the predominant phagocyte responsible for the clearance of apoptotic hepatic cells in the steady state. In contrast to the engulfment of dead cells by macrophages, neutrophils burrowed directly into apoptotic hepatocytes, a process we term perforocytosis, and ingested the effete cells from the inside. The depletion of neutrophils caused defective removal of apoptotic bodies, induced tissue injury in the mouse liver, and led to the generation of autoantibodies. Human autoimmune liver disease showed similar defects in the neutrophil-mediated clearance of apoptotic hepatic cells. Hence, neutrophils possess a specialized immunologically silent mechanism for the clearance of apoptotic hepatocytes through perforocytosis, and defects in this key housekeeping function of neutrophils contribute to the genesis of autoimmune liver disease.


Every day, the immune cells clears the remains of billions of old and damaged cells that have undergone a controlled form of death. Removing them quickly helps to prevent inflammation or the development of autoimmune diseases. While immune cells called neutrophils are generally tasked with removing invading bacteria, macrophages are thought to be responsible for clearing dead cells. However, in healthy tissue, the process occurs so efficiently that it can be difficult to confirm which cells are responsible. To take a closer look, Cao et al. focused on the liver by staining human samples to identify both immune and dead cells. Unexpectedly, there were large numbers of neutrophils visible inside dead liver cells. Further experiments in mice revealed that after entering the dead cells, neutrophils engulfed the contents and digested the dead cell from the inside out. This was a surprising finding because not only are neutrophils not usually associated with dead cells, but immune cells usually engulf cells and bacteria from the outside rather than burrowing inside them. The importance of this neutrophil behaviour was shown when Cao et al. studied samples from patients with an autoimmune disease where immune cells attack the liver. In this case, very few dead liver cells contained neutrophils, and the neutrophils themselves did not seem capable of removing the dead cells, leading to inflammation. This suggests that defective neutrophil function could be a key contributor to this autoimmune disease. The findings identify a new role for neutrophils in maintaining healthy functioning of the liver and reveal a new target in the treatment of autoimmune diseases. In the future, Cao et al. plan to explore whether compounds that enhance clearance of dead cells by neutrophils can be used to treat autoimmune liver disease in mouse models of the disease.


Asunto(s)
Enfermedades Autoinmunes , Neutrófilos , Adulto , Humanos , Animales , Ratones , Hepatocitos , Fagocitos , Macrófagos , Autoanticuerpos
17.
J Hazard Mater ; 459: 132213, 2023 10 05.
Artículo en Inglés | MEDLINE | ID: mdl-37549581

RESUMEN

Sulfate-reducing bacteria (SRB) can immobilize heavy metals in soils through biomineralization, and the parent rock and minerals in the soil are critical to the immobilization efficiency of SRB. To date, there is little knowledge about the fate of Cd associated with the parent rocks and minerals of soil during Cd immobilized by SRB. In this study, we created a model system using clay-size fraction of soil and SRB to explore the role of SRB in immobilizing Cd in soils from stratigraphic successions with high geochemical background. In the system, clay-size fractions (particle size < 2 µm) with concentration of Cd (0.24-2.84 mg/kg) were extracted from soils for bacteria inoculation. After SRB reaction for 10 days, the Cd fraction tended to transform into iron-manganese bound. Further, two clay-size fractions, i.e., the non-crystalline iron oxide (Fe-OX) and the crystalline iron oxide (Fe-CBD), were separated by extraction. The reaction of SRB with them verified the transformation of primary iron-bearing minerals into secondary iron-bearing minerals, which contributed to Cd redistribution. This study shows that SRB could exploit the composition and structure of minerals to induce mineral recrystallization, thereby aggravating Cd redistribution and immobilization in clay-size fractions from stratigraphic successions with high geochemical background.


Asunto(s)
Desulfovibrio , Contaminantes del Suelo , Arcilla , Suelo/química , Cadmio/química , Contaminantes del Suelo/análisis , Minerales/química , Hierro/metabolismo , Desulfovibrio/metabolismo , Sulfatos
18.
Sci Transl Med ; 15(709): eabm5755, 2023 08 16.
Artículo en Inglés | MEDLINE | ID: mdl-37585502

RESUMEN

Aging is a major risk factor of high incidence and increased mortality of acute respiratory distress syndrome (ARDS). Here, we demonstrated that persistent lung injury and high mortality in aged mice after sepsis challenge were attributable to impaired endothelial regeneration and vascular repair. Genetic lineage tracing study showed that endothelial regeneration after sepsis-induced vascular injury was mediated by lung resident endothelial proliferation in young adult mice, whereas this intrinsic regenerative program was impaired in aged mice. Expression of forkhead box M1 (FoxM1), an important mediator of endothelial regeneration in young mice, was not induced in lungs of aged mice. Transgenic FOXM1 expression or in vivo endothelium-targeted nanoparticle delivery of the FOXM1 gene driven by an endothelial cell (EC)-specific promoter reactivated endothelial regeneration, normalized vascular repair and resolution of inflammation, and promoted survival in aged mice after sepsis challenge. In addition, treatment with the FDA-approved DNA demethylating agent decitabine was sufficient to reactivate FoxM1-dependent endothelial regeneration in aged mice, reverse aging-impaired resolution of inflammatory injury, and promote survival. Mechanistically, aging-induced Foxm1 promoter hypermethylation in mice, which could be inhibited by decitabine treatment, inhibited Foxm1 induction after sepsis challenge. In COVID-19 lung autopsy samples, FOXM1 was not induced in vascular ECs of elderly patients in their 80s, in contrast with middle-aged patients (aged 50 to 60 years). Thus, reactivation of FoxM1-mediated endothelial regeneration and vascular repair may represent a potential therapy for elderly patients with ARDS.


Asunto(s)
COVID-19 , Proteína Forkhead Box M1 , Lesión Pulmonar , Síndrome de Dificultad Respiratoria , Sepsis , Animales , Ratones , Decitabina/farmacología , Endotelio Vascular/fisiología , Proteína Forkhead Box M1/genética , Proteína Forkhead Box M1/metabolismo , Pulmón/metabolismo , Lesión Pulmonar/genética , Ratones Transgénicos , Regeneración/fisiología , Sepsis/metabolismo
19.
ACS Nano ; 17(12): 11607-11615, 2023 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-37288740

RESUMEN

Photochemical methods are effective for controllable synthesis of silver nanoparticles with specific sizes and shapes. Whether they are capable of fabricating Ag nanoclusters (NCs) with atomic precision is yet to be proved. In this work, we synthesize an atomically precise Ag NC, [Ag25(4-MePhC≡C)20(Dpppe)3](SbF6)3 (Ag25), via a process mediated by visible light. Its total structure is determined by X-ray crystallography. The investigation of the mechanism reveals that the formation of Ag25 is triggered by a photoinduced electron-transfer (PET) process. An electron of certain amines is excited by light with wavelength shorter than 455 nm and transferred to Ag+. The amine is oxidized to the corresponding amine N-oxide. Such a PET process is supported by experimental and density functional theory studies. To expand the application scope of the photochemical method, another three NCs, [Ag19(4-tBuPhC≡C)14(Dpppe)3](SbF6)3 (Ag19), [Ag32(4-tBuPhC≡C)22(Dppp)4](SbF6)3 (Ag32), and bimetallic [Ag22Au3(4-tBuPhC≡C)20(Dpppe)3](SbF6)3 (Ag22Au3), are produced by replacing certain ingredients. Furthermore, since the formation of Ag19 can be regarded as a photochromatic process, a facile amine visual detection method is also presented based on this mechanism.

20.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 35(4): 442-445, 2023 Apr.
Artículo en Chino | MEDLINE | ID: mdl-37308205

RESUMEN

For patients receiving mechanical ventilation, mechanical ventilation is also an injury factor at the same time of treatment, which can lead to or aggravate lung injury, that is, ventilator-induced lung injury (VILI). The typical feature of VILI is that the mechanical stress is transmitted to cells through the pathway, leading to uncontrollable inflammatory cascade reaction, which causes the activation of inflammatory cells in the lung and the release of a large number of cytokines and inflammatory mediators. Among them, innate immunity is also involved in the occurrence and development of VILI. A large number of studies have shown that damaged lung tissue in VILI can regulate inflammatory response by releasing a large number of damage associated molecular pattern (DAMP). Pattern recognition receptor (PRR) participates in the activation of immune response by combining with DAMP, and releases a large number of inflammatory mediators to promote the occurrence and development of VILI. Recent studies have shown that inhibition of DAMP/PRR signaling pathway can play a protective role in VILI. Therefore, this article will mainly discuss the potential role of blocking DAMP/PRR signal pathway in VILI, and provide new ideas for the treatment of VILI.


Asunto(s)
Respiración Artificial , Lesión Pulmonar Inducida por Ventilación Mecánica , Humanos , Respiración , Inmunidad Innata , Inflamación , Mediadores de Inflamación , Pulmón
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