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Human genetic evidence suggests a protective role of loss-of-function variants in 17-beta hydroxysteroid dehydrogenase 13 (HSD17B13) for liver fibrotic diseases. Although there is limited preclinical experimental data on Hsd17b13 antisense oligonucleotide (ASO) or siRNA in a fibrosis model, several ASO and siRNA approaches are being tested clinically as potential therapies for nonalcoholic steatohepatitis (NASH). The aim of this study was to assess the therapeutic potential of Hsd17b13 ASO in a preclinical advanced NASH-like hepatic fibrosis in vivo model. In vitro testing on primary hepatocytes demonstrated that Hsd17b13 ASO exhibited strong efficacy and specificity for knockdown of the Hsd17b13 gene. In choline-deficient, L-amino acid-defined, HFD (CDAHFD)-induced steatotic and fibrotic mice, therapeutic administration of Hsd17b13 ASO resulted in a significant and dose-dependent reduction of hepatic Hsd17b13 gene expression. The CDAHFD group exhibited considerably elevated liver enzyme levels, hepatic steatosis score, hepatic fibrosis, and increased fibrotic and inflammatory gene expression, indicating an advanced NASH-like hepatic fibrosis phenotype. Although Hsd17b13 ASO therapy significantly affected hepatic steatosis, it had no effect on hepatic fibrosis. Our findings demonstrate, for the first time, that Hsd17b13 ASO effectively suppressed Hsd17b13 gene expression both in vitro and in vivo, and had a modulatory effect on hepatic steatosis in mice, but did not affect fibrosis in the CDAHFD mouse model of NASH.
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Hepatopatia Gordurosa não Alcoólica , Animais , Camundongos , Modelos Animais de Doenças , Fígado/metabolismo , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/genética , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/genética , Oligonucleotídeos Antissenso/genética , Oligonucleotídeos Antissenso/farmacologia , Oligonucleotídeos Antissenso/uso terapêutico , RNA Interferente Pequeno/metabolismoRESUMO
Actuating materials convert different forms of energy into mechanical responses. To satisfy various application scenarios, they are desired to have rich categories, novel functionalities, clear structure-property relationships, fast responses, and, in particular, giant and reversible shape changes. Herein, we report a phase transition-driven ferroelectric crystal, (rac-3-HOPD)PbI3 (3-HOPD = 3-hydroxypiperidine cation), showing intriguingly large and anisotropic room-temperature actuating behaviors. The crystal consists of rigid one-dimensional [PbI3] anionic chains running along the a-axis and discrete disk-like cations loosely wrapping around the chains, leaving room for anisotropic shape changes in both the b- and c-axes. The shape change is switched by a ferroelectric phase transition occurring at around room temperature (294 K), driven by the exceptionally synergistic order-disorder and displacive phase transition. The rotation of the cations exerts internal pressure on the stacking structure to trigger an exceptionally large displacement of the inorganic chains, corresponding to a crystal lattice transformation with length changes of +24.6% and -17.5% along the b- and c-axis, respectively. Single crystal-based prototype devices of circuit switches and elevators have been fabricated by exploiting the unconventional negative temperature-dependent actuating behaviors. This work provides a new model for the development of multifunctional mechanically responsive materials.
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Metal halide perovskites (MHPs) have garnered significant attention due to their distinctive optical and electronic properties, coupled with excellent processability. However, the thermal characteristics of these materials are often overlooked, which can be harnessed to cater to diverse application scenarios. We showcase the efficacy of lowering the congruent melting temperature (Tm) of layered 2D MHPs by employing a strategy that involves the modification of flexible alkylammonium through N-methylation and I-substitution. Structural-property analysis reveals that the N-methylation and I-substitution play pivotal roles in reducing hydrogen bond interactions between the organic components and inorganic parts, lowering the rotational symmetry number of the cation and restricting the residual motion of the cations. Additional I···I interactions enhance intermolecular interactions and lead to improved molten stability, as evidenced by a higher viscosity. The 2D MHPs discussed in this study exhibit low Tm and wide melt-processable windows, e.g., (DMIPA)2PbI4 showcasing a low Tm of 98 °C and large melt-processable window of 145 °C. The efficacy of the strategy was further validated when applied to bromine-substituted 2D MHPs. Lowering the Tm and enhancing the molten stability of the MHPs hold great promise for various applications, including glass formation, preparation of high-quality films for photodetection, and fabrication of flexible devices.
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OBJECTIVE: Connective tissue growth factor (CTGF) exhibits potent proliferative, differentiated, and mineralizing effects, and is believed to be contribute to cartilage mineralization in Osteoarthritis (OA). However, the underlying mechanism of chondrocyte mineralization induced by CTGF remains obscure. As a key regulator of mineral responses, type III phosphate transporter 1 (Pit-1) has been associated with the pathogenesis of articular mineralization. Therefore, the primary objective of this study was to investigate whether CTGF influences the development of mature chondrocyte mineralization and the underlying mechanisms governing such mineralization. METHODS: The effect of Connective tissue growth factor (CTGF) on human C-28/I2 chondrocytes were investigated. The chondrocytes were treated with CTGF or related inhibitors, and transfected with Overexpression and siRNA transfection of Type III Phosphate Transporter 1(Pit-1). Subsequently, the cells were subjected to Alizarin red S staining, PiPer Phosphate Assay Kit, Alkaline Phosphatase Diethanolamine Activity Kit, ELISA, RT-PCR or Western blot analysis. RESULTS: Stimulation with Connective tissue growth factor (CTGF) significantly upregulated the expression of the Type III Phosphate Transporter 1(Pit-1) and mineralization levels in chondrocytes through activation of α5ß1 integrin and BMP/Samd1/5/8 signaling pathways. Furthermore, treatment with overexpressed Pit-1 markedly increased the expression of Multipass Transmembrane Ankylosis (ANK) transporter in the cells. The inhibitory effect of CTGF receptor blockade using α5ß1 Integrin blocking antibody was demonstrated by significantly suppressed the expression of Pit-1 and ANK transporter, as well as chondrocyte mineralization. CONCLUSIONS: Our data indicate that Connective tissue growth factor (CTGF) plays a critical role inchondrocyte mineralization, which is dependent on the expression of the Type III Phosphate Transporter 1(Pit-1) and Multipass Transmembrane Ankylosis (ANK) transporter. Consequently, inhibition of CTGF activity may represent a novel therapeutic approach for the management of Osteoarthritis (OA).
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Anquilose , Calcinose , Osteoartrite , Humanos , Anquilose/metabolismo , Anquilose/patologia , Calcinose/patologia , Células Cultivadas , Condrócitos/metabolismo , Fator de Crescimento do Tecido Conjuntivo/genética , Fator de Crescimento do Tecido Conjuntivo/metabolismo , Integrinas/metabolismo , Osteoartrite/metabolismo , Proteínas de Transporte de Fosfato/genética , Proteínas de Transporte de Fosfato/metabolismoRESUMO
Lithium-sulfur batteries (LSBs) are considered as the development direction of the new generation energy storage system due to their high energy density and low cost. The slow redox kinetics of sulfur and the shuttle effect of lithium polysulfide (LiPS) are considered to be the main obstacles to the practical application of LSBs. Transition-metal sulfide as the cathode host can improve the Li-S redox chemistry. However, there has been no investigation of the application of FeS2 host in Li-S redox chemistry. Applying the first-principles calculations, we investigated the formation energy, band gap, Li+ diffusion, adsorption energy, catalytic performance and Li2 S decomposition barrier of FeAx S2-x (A=N, P, O, Se; x=0, 0.125, 0.25, 0.375) to explore the Li-S redox chemistry and finally select excellent host material. FeA0.25 S1.75 (A=P, Se) has a low Li+ diffusion barrier and superior electronic conductivity. FeO0.25 S1.75 is more favorable for LiPS adsorption, followed by FeP0.25 S1.75 . FeP0.25 S1.75 (001) shows a low overpotential for the Li-S redox chemistry. In summary, FeP0.25 S1.75 has more application potential in LSBs due to its physical and chemical properties, followed by FeSe0.25 S1.75 . This work provides theoretical guidance for the design and selection of the sulfur cathode host materials in LSBs.
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As a result of our continued efforts to pursue Gal-3 inhibitors that could be used to fully evaluate the potential of Gal-3 as a therapeutic target, two novel series of benzothiazole derived monosaccharides as potent (against both human and mouse Gal-3) and orally bioavailable Gal-3 inhibitors, represented by 4 and 5, respectively, were identified. These discoveries were made based on proposals that the benzothiazole sulfur atom could interact with the carbonyl oxygen of G182/G196 in h/mGal-3, and that the anomeric triazole moiety could be modified into an N-methyl carboxamide functionality. The interaction between the benzothiazole sulfur and the carbonyl oxygen of G196 in mGal-3 was confirmed by an X-ray co-crystal structure of early lead 9, providing a rare example of using a S···O binding interaction for drug design. It was found that for both the series, methylation of 3-OH in the monosaccharides caused no loss in h & mGal-3 potencies but significantly improved permeability of the molecules.
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Galectina 3 , Monossacarídeos , Animais , Humanos , Camundongos , Benzotiazóis/química , Benzotiazóis/farmacologia , Desenho de Fármacos , Galectina 3/antagonistas & inibidores , Galectinas/antagonistas & inibidores , Monossacarídeos/química , Monossacarídeos/farmacologia , Oxigênio , EnxofreRESUMO
Lithium-sulfur batteries (LSBs) are one of the most promising energy storage devices with high energy density. However, their application and commercialization are hampered by the slow Li-S redox chemistry. Fe0.875M0.125S2 (M = Ti, V), as the sulfur cathode host, enhances the Li-S redox chemistry. FeS2 with Pa3Ì is transformed into Li2FeS2 with P3Ìm1 after discharge. The structure changes and physicochemical properties during Fe0.875M0.125S2 discharge process are further investigated to screen out the sulfur cathode host materials with the best comprehensive properties. The discharge structure of Fe0.875M0.125S2 is verified by the thermodynamic stability of Li-deficient phases, voltage and capacity based on Monte Carlo methods. Fe0.875M0.125S2 with Pa3Ì is transformed into Li2Fe0.875M0.125S2 with P3Ìm1 after discharge. Using the first-principles calculations, the physicochemical properties of Li2Fe0.875M0.125S2 are systematically investigated, including the formation energy, voltage, theoretical capacity, electrical conductivity, Li+ diffusion, catalytic performance and Li2S oxidation decomposition. The average redox voltage of Li2Fe0.875V0.125S2 is higher than that of Li2Fe0.875Ti0.125S2. Li2Fe0.875M0.125S2 shows metallic properties. Li2Fe0.875V0.125S2 is more beneficial to the reduction reaction of Li2S2 and Li2S oxidation decomposition. Fe0.875V0.125S2 has more potential as the sulfur cathode host than Fe0.875Ti0.125S2 in LSBs. A new strategy for the selection of the sulfur cathode host material for LSBs is provided by this work.
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INTRODUCTION: There is a paucity of real-world studies examining the risks of stroke/systemic embolism (SE) and major bleeding (MB) among non-valvular atrial fibrillation (NVAF) patients switching from warfarin to a direct oral anticoagulant (DOAC). This retrospective study was conducted to compare the stroke/SE and MB risks between patients switched from warfarin to apixaban, dabigatran, or rivaroxaban in real-world clinical practice. MATERIALS AND METHODS: This study used data from four United States commercial claims databases from January 1, 2012 to June 30, 2019. The study population included NVAF patients initially treated with warfarin and switched to apixaban, dabigatran, or rivaroxaban within 90 days of their warfarin prescription ending. Patients were matched 1:1 between the DOACs in each database using propensity scores and then pooled for the final analysis. Cox proportional hazards models were used to calculate the risk of stroke/SE and MB. RESULTS AND CONCLUSIONS: The final population consisted of 2,611 apixaban-dabigatran, 12,165 apixaban-rivaroxaban, and 2,672 dabigatran-rivaroxaban pairs. Apixaban vs. dabigatran was associated with a lower risk of stroke/SE (hazard ratio [HR]: 0.61; 95% confidence interval [CI]: 0.39-0.96) and MB (HR: 0.67; 95% CI: 0.50-0.91). Apixaban vs. rivaroxaban was associated with a similar risk of stroke/SE (HR: 0.88; 95% CI: 0.73-1.07) and a lower risk of MB (HR: 0.60; 95% CI: 0.52-0.68). There was no significant difference in either risk between dabigatran and rivaroxaban. These results provide important insights into how the risks of stroke/SE and MB for NVAF patients vary when switching from warfarin to different DOACs.
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Anticoagulantes , Fibrilação Atrial , Dabigatrana , Hemorragia , Pirazóis , Piridonas , Rivaroxabana , Acidente Vascular Cerebral , Varfarina , Humanos , Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/complicações , Varfarina/efeitos adversos , Varfarina/uso terapêutico , Varfarina/administração & dosagem , Masculino , Feminino , Idoso , Estudos Retrospectivos , Estados Unidos/epidemiologia , Rivaroxabana/uso terapêutico , Rivaroxabana/efeitos adversos , Rivaroxabana/administração & dosagem , Dabigatrana/efeitos adversos , Dabigatrana/uso terapêutico , Dabigatrana/administração & dosagem , Pirazóis/efeitos adversos , Pirazóis/uso terapêutico , Pirazóis/administração & dosagem , Acidente Vascular Cerebral/prevenção & controle , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/epidemiologia , Pessoa de Meia-Idade , Piridonas/efeitos adversos , Piridonas/uso terapêutico , Piridonas/administração & dosagem , Anticoagulantes/uso terapêutico , Anticoagulantes/efeitos adversos , Anticoagulantes/administração & dosagem , Hemorragia/induzido quimicamente , Administração Oral , Substituição de Medicamentos , Embolia/prevenção & controle , Embolia/etiologia , Embolia/epidemiologia , Resultado do TratamentoRESUMO
Liriomyza trifolii, an invasive pest, poses a substantial threat to horticultural and vegetable plants. It spreads rapidly, especially in hot weather, leading to large-scale outbreaks with strong thermotolerance and insecticide resistance. In this study, mortality and LtCYP4g1 expression in L. trifolii were evaluated after thermal and insecticides exposure. Furthermore, functional verification of LtCYP4g1 was conducted through RNA interference and bacterial survival assays in Escherichia coli containing recombinant LtCYP4g1 protein. Results indicated that a short time exposure to high temperature incresed insecticide tolerance of L. trifolii, attributed to decreased mortality and induced LtCYP4g1 expression; LtCYP4g1 was involved in stimulating synthesis of cuticular hydrocarbons (CHCs) and elevating epicuticle lipid content and thickness, and E. coli cells overexpressing LtCYP4g1 exhibited significant tolerance to thermal and insecticide stress. In general, P450-mediated tolerance of L. trifolii was enhanced by high temperature, with LtCYP4g1 playing a role in promoting biosynthesis of CHCs for thickening epidermal lipid barrier and reducing cuticular penetration. This study provides a framework for delving into the function of CYP450s in insecticide detoxification and illustrates the role of global warming in driving the evolution of L. trifolii.
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Sistema Enzimático do Citocromo P-450 , Inseticidas , Ivermectina , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Animais , Inseticidas/farmacologia , Ivermectina/análogos & derivados , Ivermectina/farmacologia , Resistência a Inseticidas/genética , Hidrocarbonetos/metabolismo , Temperatura Alta , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Besouros/efeitos dos fármacos , Besouros/genética , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismoRESUMO
This paper proposes a solution to the problem of mobile robot navigation and trajectory interpolation in dynamic environments with large scenes. The solution combines a semantic laser SLAM system that utilizes deep learning and a trajectory interpolation algorithm. The paper first introduces some open-source laser SLAM algorithms and then elaborates in detail on the general framework of the SLAM system used in this paper. Second, the concept of voxels is introduced into the occupation probability map to enhance the ability of local voxel maps to represent dynamic objects. Then, in this paper, we propose a PointNet++ point cloud semantic segmentation network combined with deep learning algorithms to extract deep features of dynamic point clouds in large scenes and output semantic information of points on static objects. A descriptor of the global environment is generated based on its semantic information. Closed-loop completion of global map optimization is performed to reduce cumulative error. Finally, T-trajectory interpolation is utilized to ensure the motion performance of the robot and improve the smooth stability of the robot trajectory. The experimental results indicate that the combination of the semantic laser SLAM system with deep learning and the trajectory interpolation algorithm proposed in this paper yields better graph-building and loop-closure effects in large scenes at SIASUN large scene campus. The use of T-trajectory interpolation ensures vibration-free and stable transitions between target points.
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Dormancy release and reactivation in temperate trees are mainly controlled by temperature and are affected by age, but the underlying molecular mechanisms are still unclear. In this study, we explored the effects of low temperatures in winter and warm temperatures in spring on dormancy release and reactivation in Larix kaempferi. Further, we established the relationships between cell-cycle genes and cambium cell division. The results showed that chilling accelerated L. kaempferi bud break overall, and the longer the duration of chilling is, the shorter the bud break time is. After dormancy release, warm temperatures induced cell-cycle gene expression; when the configuration value of the cell-cycle genes reached 4.97, the cambium cells divided and L. kaempferi reactivated. This study helps to predict the impact of climate change on wood production and provides technical support for seedling cultivation in greenhouses.
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Larix , Larix/genética , Câmbio , Genes cdc , Divisão Celular , Mudança ClimáticaRESUMO
Biotin, also known as vitamin H or B7, acts as a crucial cofactor in the central metabolism processes of fatty acids, amino acids, and carbohydrates. Biotin has important applications in food additives, biomedicine, and other fields. While the ability to synthesize biotin de novo is confined to microorganisms and plants, humans and animals require substantial daily intake, primarily through dietary sources and intestinal microflora. Currently, chemical synthesis stands as the primary method for commercial biotin production, although microbial biotin production offers an environmentally sustainable alternative with promising prospects. This review presents a comprehensive overview of the pathways involved in de novo biotin synthesis in various species of microbes and insights into its regulatory and transport systems. Furthermore, diverse strategies are discussed to improve the biotin production here, including mutation breeding, rational metabolic engineering design, artificial genetic modification, and process optimization. The review also presents the potential strategies for addressing current challenges for industrial-scale bioproduction of biotin in the future. This review is very helpful for exploring efficient and sustainable strategies for large-scale biotin production.
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Aminoácidos , Biotina , Animais , Humanos , Biotecnologia , Ácidos Graxos , Aditivos AlimentaresRESUMO
In this study, a mouse model of premature ovarian failure(POF) was constructed by injecting D-galactose(200 mg·kg~(-1)) into the back of the neck for 6 weeks. The mice were randomly divided into a normal group(group N), a model group(group M), and a Qiwei Guibao Granules group(group A, 12.87 g·kg~(-1)). Starting from the 11th day of modeling, group A was treated with Qiwei Guibao Granules by gavage for 32 days, while group M and group N were given equal volume of saline. Metabolomics analysis was used to explore the mechanism of action of Qiwei Guibao Granules in the treatment of POF. The results showed that compared with group N, the group M exhibited decreased wet weight of bilateral ovaries, increased levels of LH and FSH in serum, and significantly decreased levels of E_2 and PROG. After treatment with Qiwei Guibao Granules, compared with the group M, the group A showed a significant increase in the wet weight of bilateral ovaries, a significant decrease in the levels of FSH and LH in serum, and a significant increase in the level of E_2. Metabolomics analysis revealed 55 differential metabolites identified between group N and group M(14 upregulated and 41 downregulated compared with group N) and 82 differential metabolites identified between group M and group A(56 upregulated and 26 downregulated compared with group M), with 5 metabolites showing consistent changes between the group N vs group M. After excluding these 5 metabolites, 77 metabolites that changed after intervention with Qiwei Guibao Granules were focused on. These mainly involved histidine metabolism, glycine, serine, and threonine metabolism, and glycerophospholipid metabolism. Among them, carnosine, 1-methyl-L-histidine, imidazoleacetic acid, choline, L-threonine, beta-hydroxypyruvic acid, phosphatidylcholine, and glycerol-3-phosphate were the major differential metabolites in these three metabolic pathways. Therefore, Qiwei Guibao Granules may exert therapeutic effects on POF mice by regulating amino acid metabolism and lipid metabolism in the mouse body.
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Medicamentos de Ervas Chinesas , Metabolômica , Insuficiência Ovariana Primária , Animais , Feminino , Insuficiência Ovariana Primária/tratamento farmacológico , Insuficiência Ovariana Primária/metabolismo , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/farmacologia , Camundongos , Humanos , Ovário/efeitos dos fármacos , Ovário/metabolismo , Modelos Animais de DoençasRESUMO
A mononuclear valence tautomeric (VT) complex, [Co(pycz)2(Sq)(Cat)] (1-trans), where pycz = 9-(pyridin-4-yl)-9H-carbazole, Sqâ - = 3,5-di-tert-butyl-semiquinonato, and Cat2- = 3,5-di-tert-butyl-catecholato, is synthesized in the trans configuration, which undergoes one-step valence tautomeric transition above room temperature. Remarkably, 1-trans can transform into its isomeric structure, [Co(pycz)2(Sq)(Sq)] (1-cis), at temperature above 350â K in a single-crystal-to-single-crystal way by in situ molecular twist, and the resulting 1-cis exhibits a pronounced two-step VT transition during magnetic measurements that is rare for mononuclear VT complexes. Such drastic solid-state structural transformation is reported in VT compounds for the first time, which is actuated by a crystal surface's melting-recrystallization induced phase transition process. DFT calculations offer an underlying mechanism suggesting a concerted bond rotation during the structural transformation. The results demonstrate an unconventional approach that realizes structural transformation of VT complexes and the control of VT performance.
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PURPOSE: To explore the influence of gingival biotype and width of keratinized gingiva on peri-implant bone tissue, soft tissue health, and esthetic outcome of the papilla surrounding single posterior maxillary implants. METHODS: Seventy-eight patients who underwent single posterior maxillary implant surgery from May 2019 to September 2022 were selected, involving the placement of 78 implants. Based on periodontal probing outcomes one month post-restoration, the patients were divided into thin gingival biotype group(n=32) and thick gingival biotype group(n=46). Comparisons were made six months after implant restoration regarding buccal keratinized mucosa width(KMW), peri-implant bone tissue [implant bone loss(IBL)], soft tissue health [modified plaque index (mPLI), modified bleeding index for implants (mBLI), probing pocket depth (PPD)], and esthetic effect of the papilla [papilla index score (PIS), food impaction, gingival margin color satisfaction index (GMCS)]. Statistical analysis was performed with SPSS 27.0 software package. RESULTS: The thick gingival biotype group showed significantly greater keratinized gingival width compared to the thin gingival biotype group (Pï¼0.05). Spearman correlation analysis revealed a positive correlation between gingival biotype and keratinized gingival width(r=-0.416, P=0.000). For peri-implant bone tissue, bone loss in the thin gingival biotype group was significantly higher than that in the thick gingival biotype group. In soft tissue health, the probing pocket depth for implants in the thin gingival biotype group was significantly less than that in the thick gingival biotype group. In terms of esthetic effect of the papilla, PES score in the thin gingival biotype group was significantly lower than in the thick gingival biotype group(Pï¼0.05). Pearson correlation analysis showed a negative correlation between gingival biotype and papilla index score, GMCS, bleeding on probing, and PPD, but a positive correlation with food impaction, bone loss and mPLI(Pï¼0.05). The width of keratinized gingiva was positively correlated with papilla index score, GMCS, bleeding on probing and PPD, but negatively correlated with food impaction, bone loss and mPLI(Pï¼0.05). There was significantly difference between thin and thick gingival biotype groups for KMW >2 mm(Pï¼0.05). A significant difference was showed in thick gingival biotype group when KMW ≤2 mm and ï¼2 mm(Pï¼0.05). CONCLUSIONS: Gingival biotype and keratinized mucosa width significantly influence peri-implant bone and soft tissue health as well as esthetic outcome of the papilla around single posterior maxillary implants, offering guidance for predicting the long-term success and esthetic outcomes of implants.
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Estética Dentária , Gengiva , Maxila , Humanos , Gengiva/anatomia & histologia , Gengiva/cirurgia , Maxila/anatomia & histologia , Maxila/cirurgia , Índice Periodontal , Implantes Dentários para Um Único Dente , Índice de Placa DentáriaRESUMO
The real-time monitoring of volatile sulfur compounds is indispensable; however, it continues to pose a significant challenge due to issues such as limited performance towards parts-per-billion (ppb)-level gas. Herein, a concept of synergistic sensitization effects involving single-atom gold (Au) and cerium (Ce) dopants is proposed to boost the sensing performance of allyl mercaptan, a common volatile sulfur compound. As a proof-of-concept, a chemiresistive gas sensor based on mesoporous SnO2 nanospheres with single-atom Au decoration and Ce dopant (denoted Au/Ce-SnO2) is successfully synthesized. The synthesis of Au/Ce-SnO2 is achieved through the utilization of a self-template strategy, employing metal-phenolic hybrids as a precursor. The obtained materials exhibit high specific surface area (89.4 m2 g-1), and small particle size (â¼86 nm). The gas sensor reveals unprecedented sensitivity (0.097 ppb-1) and ultra-low detection limit (0.74 ppb), surpassing all state-of-the-art allyl mercaptan gas sensors. Furthermore, a wireless gas sensor is constructed for highly selective and real-time monitoring of allyl mercaptan. The decoration of single-atom Au facilitates the adsorption and dissociation of oxygen and target gases. Simultaneously, the Ce dopant enhances the oxidation of allyl mercaptan. The sensing performance is boosted by the mesoporous framework of SnO2, as well as the synergistic sensitization effects resulting from single-atom Au decoration and Ce doping, thereby facilitating its potential application in environmental and health-related domains.
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Achieving ultrasensitive and rapid detection of 3-methylbutyraldehyde is crucial for monitoring chemical intermediate leakage in pharmaceutical and chemical industries as well as diagnosing ventilator-associated pneumonia by monitoring exhaled gas. However, developing a sensitive and rapid method for detecting 3-methylbutyraldehyde poses challenges. Herein, a wireless chemiresistive gas sensor based on a mesoporous ZnO-SnO2 heterostructure is fabricated to enable the ultrasensitive and rapid detection of 3-methylbutyraldehyde for the first time. The mesoporous ZnO-SnO2 heterostructure exhibits a uniform spherical shape (â¼79 nm in diameter), a high specific surface area (54.8 m2 g-1), a small crystal size (â¼4 nm), and a large pore size (6.7 nm). The gas sensor demonstrates high response (18.98@20 ppm), short response/recovery times (13/13 s), and a low detection limit (0.48 ppm) toward 3-methylbutyraldehyde. Furthermore, a real-time monitoring system is developed utilizing microelectromechanical systems gas sensors. The modification of amorphous ZnO on the mesoporous SnO2 pore wall can effectively increase the chemisorbed oxygen content and the thickness of the electron depletion layer at the gas-solid interface, which facilitates the interface redox reaction and enhances the sensing performance. This work presents an initial example of semiconductor metal oxide gas sensors for efficient detection of 3-methylbutyraldehyde that holds great potential for ensuring safety during chemical production and disease diagnosis.
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Compostos de Estanho , Óxido de Zinco , Óxido de Zinco/química , Compostos de Estanho/química , Porosidade , Limite de Detecção , Aldeídos/química , Gases/química , Gases/análise , Tecnologia sem FioRESUMO
Various liver diseases pose great threats to humans. Although the etiologies of these liver diseases are quite diverse, they share similar pathologic phenotypes and molecular mechanisms such as oxidative stress, lipid and glucose metabolism disturbance, hepatic Kupffer cell (KC) proinflammatory polarization and inflammation, insulin resistance, and hepatic stellate cell (HSC) activation and proliferation. Peroxisome proliferator-activated receptor ß/δ (PPARß/δ) is expressed in various types of liver cells with relatively higher expression in KCs and HSCs. Accumulating evidence has revealed the versatile functions of PPARß/δ such as controlling lipid homeostasis, inhibiting inflammation, regulating glucose metabolism, and restoring insulin sensitivity, suggesting that PPARß/δ may serve as a potential molecular drug target for various liver diseases. This article aims to provide a concise review of the structure, expression pattern and biological functions of PPARß/δ in the liver and its roles in various liver diseases, and to discuss potential future research perspectives.