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1.
Proc Natl Acad Sci U S A ; 121(2): e2314996121, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38165931

RESUMO

Converting hydrocarbons and greenhouse gases (i.e., carbon dioxide, CO2) directly into electricity through fuel cells at intermediate temperatures (450 to 550 °C) remains a significant challenge, primarily due to the sluggish activation of C-H and C=O bonds. Here, we demonstrated a unique strategy to address this issue, in which light illumination was introduced into the thermal catalytic CO2 reforming of ethane in the anode as a unique thermo-photo anode process for carbonate-superstructured solid fuel cells. The light-enhanced fuel activation led to excellent cell performance with a record-high peak power density of 168 mW cm-2 at an intermediate temperature of 550 °C. Furthermore, no degradation was observed during ~50 h operation. Such a successful integration of photo energy into the fuel cell system provides a new direction for the development of efficient fuel cells.

2.
Genome Res ; 33(5): 779-786, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37295844

RESUMO

Tandem duplications are frequent structural variations of the genome and play important roles in genetic disease and cancer. However, interpreting the phenotypic consequences of tandem duplications remains challenging, in part owing to the lack of genetic tools to model such variations. Here, we developed a strategy, tandem duplication via prime editing (TD-PE), to create targeted, programmable, and precise tandem duplication in the mammalian genome. In this strategy, we design a pair of in trans prime editing guide RNAs (pegRNAs) for each targeted tandem duplication, which encode the same edits but prime the single-stranded DNA (ssDNA) extension in opposite directions. The reverse transcriptase (RT) template of each extension is designed homologous to the target region of the other single guide RNA (sgRNA) to promote the reannealing of the edited DNA strands and the duplication of the fragment in between. We showed that TD-PE produced robust and precise in situ tandem duplications of genomic fragments ranging from ∼50 bp to ∼10 kb, with a maximal efficiency up to 28.33%. By fine-tuning the pegRNAs, we achieved simultaneous targeted duplication and fragment insertion. Finally, we successfully produced multiple disease-relevant tandem duplications, showing the general utility of TD-PE in genetic research.


Assuntos
DNA , Genoma , Animais , DNA/genética , Genômica , Sistemas CRISPR-Cas , Mamíferos/genética
3.
Proc Natl Acad Sci U S A ; 120(12): e2219950120, 2023 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-36913567

RESUMO

High areal capacitance for a practical supercapacitor electrode requires both large mass loading and high utilization efficiency of electroactive materials, which presents a great challenge. Herein, we demonstrated the unprecedented synthesis of superstructured NiMoO4@CoMoO4 core-shell nanofiber arrays (NFAs) on a Mo-transition-layer-modified nickel foam (NF) current collector as a new material, achieving the synergistic combination of highly conductive CoMoO4 and electrochemical active NiMoO4. Moreover, this superstructured material exhibited a large gravimetric capacitance of 1,282.2 F/g in 2 M KOH with a mass loading of 7.8 mg/cm2, leading to an ultrahigh areal capacitance of 10.0 F/cm2 that is larger than any reported values of CoMoO4 and NiMoO4 electrodes. This work provides a strategic insight for rational design of electrodes with high areal capacitances for supercapacitors.

4.
PLoS Pathog ; 19(8): e1011594, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37611054

RESUMO

Treponema pallidum (Tp) has a well-known ability to evade the immune system and can cause neurosyphilis by invading the central nervous system (CNS). Microglia are resident macrophages of the CNS that are essential for host defense against pathogens, this study aims to investigate the interaction between Tp and microglia and the potential mechanism. Here, we found that Tp can exert significant toxic effects on microglia in vivo in Tg (mpeg1: EGFP) transgenic zebrafish embryos. Single-cell RNA sequencing results showed that Tp downregulated autophagy-related genes in human HMC3 microglial cells, which is negatively associated with apoptotic gene expression. Biochemical and cell biology assays further established that Tp inhibits microglial autophagy by interfering with the autophagosome-lysosome fusion process. Transcription factor EB (TFEB) is a master regulator of lysosome biogenesis, Tp activates the mechanistic target of rapamycin complex 1 (mTORC1) signaling to inhibit the nuclear translocation of TFEB, leading to decreased lysosomal biogenesis and accumulated autophagosome. Importantly, the inhibition of autophagosome formation reversed Tp-induced apoptosis and promoted microglial clearance of Tp. Taken together, these findings show that Tp blocks autophagic flux by inhibiting TFEB-mediated lysosomal biosynthesis in human microglia. Autophagosome accumulation was demonstrated to be a key mechanism underlying the effects of Tp in promoting apoptosis and preventing itself from clearing by human microglia. This study offers novel perspectives on the potential mechanism of immune evasion employed by Tp within CNS. The results not only establish the pivotal role of autophagy dysregulation in the detrimental effects of Tp on microglial cells but also bear considerable implications for the development of therapeutic strategies against Tp, specifically involving mTORC1 inhibitors and autophagosome formation inhibitors, in the context of neurosyphilis patients.


Assuntos
Microglia , Neurossífilis , Humanos , Animais , Treponema pallidum/genética , Peixe-Zebra , Autofagia , Apoptose
5.
FASEB J ; 38(19): e70082, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39344592

RESUMO

Nasal obstruction leads to a hypoxia condition throughout the entire body. In this study, the unilateral nasal obstruction (UNO) mouse model was established by blocking the left nostril of mice. The aim of this study was to investigate the effects of UNO-induced hypoxia on mandibular condyle in juvenile (3-week-old), adolescent (6-week-old) and adult (12-week-old) male C57BL/6J mice from the perspective of H-type angiogenesis coupling osteogenesis. Firstly, UNO exerted a significant inhibitory effect on weight gain in mice of all ages. However, only in adolescent mice did UNO have an obvious detrimental effect on femoral bone mass accrual. Subsequently, micro-computed tomography (CT) analysis of mandibular condylar bone mass revealed that UNO significantly retarded condylar head volume gain but increased condylar head trabecular number (Tb.N) in juvenile and adolescent mice. Furthermore, UNO promoted the ratio of proliferative layer to cartilage layer in condylar cartilage and facilitated the chondrocyte-to-osteoblast transformation in juvenile and adolescent mice. Moreover, although UNO enhanced the positive expression of hypoxia-inducible factor (HIF)-1α in the condylar subchondral bone of mice in all ages, an increase in H-type vessels and Osterix+ cells was only detected in juvenile and adolescent mice. In summary, on the one hand, in terms of condylar morphology, UNO has a negative effect on condylar growth, hindering the increase in condylar head volume in juvenile and adolescent mice. However, on the other hand, in terms of condylar microstructure, UNO has a positive effect on condylar osteogenesis, promoting the increase of condylar Tb.N, chondrocyte-to-osteoblast transformation, HIF-1α expression, H-type angiogenesis and Osterix+ cells in juvenile and adolescent mice. Although the changes in condylar morphology and microstructure caused by UNO have not yet been fully elucidated, these findings improve our current understanding of the effects of UNO on condylar bone homeostasis.


Assuntos
Côndilo Mandibular , Camundongos Endogâmicos C57BL , Obstrução Nasal , Osteogênese , Animais , Côndilo Mandibular/patologia , Côndilo Mandibular/metabolismo , Camundongos , Masculino , Osteogênese/fisiologia , Obstrução Nasal/fisiopatologia , Obstrução Nasal/patologia , Obstrução Nasal/metabolismo , Neovascularização Fisiológica/fisiologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Microtomografia por Raio-X , Condrócitos/metabolismo , Condrócitos/patologia , Osteoblastos/metabolismo , Angiogênese
6.
EMBO Rep ; 24(4): e56271, 2023 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-36718777

RESUMO

Although strongly influenced by environmental conditions, lateral root (LR) positioning along the primary root appears to follow obediently an internal spacing mechanism dictated by auxin oscillations that prepattern the primary root, referred to as the root clock. Surprisingly, none of the hitherto characterized PIN- and ABCB-type auxin transporters seem to be involved in this LR prepatterning mechanism. Here, we characterize ABCB15, 16, 17, 18, and 22 (ABCB15-22) as novel auxin-transporting ABCBs. Knock-down and genome editing of this genetically linked group of ABCBs caused strongly reduced LR densities. These phenotypes were correlated with reduced amplitude, but not reduced frequency of the root clock oscillation. High-resolution auxin transport assays and tissue-specific silencing revealed contributions of ABCB15-22 to shootward auxin transport in the lateral root cap (LRC) and epidermis, thereby explaining the reduced auxin oscillation. Jointly, these data support a model in which LRC-derived auxin contributes to the root clock amplitude.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Transporte Biológico , Proteínas de Membrana Transportadoras/genética , Ácidos Indolacéticos , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas
7.
Proc Natl Acad Sci U S A ; 119(41): e2208750119, 2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-36191218

RESUMO

A basic requirement for solid oxide fuel cells (SOFCs) is the sintering of electrolyte into a dense impermeable membrane to prevent the mixing of fuel and oxygen for a sufficiently high open-circuit voltage (OCV). However, herein, we demonstrate a different type of fuel cell, a carbonate-superstructured solid fuel cell (CSSFC), in which in situ generation of superstructured carbonate in the porous samarium-doped ceria layer creates a unique electrolyte with ultrahigh ionic conductivity of 0.17 S⋅cm-1 at 550 °C. The CSSFC achieves unprecedented high OCVs (1.051 V at 500 °C and 1.041 V at 550 °C) with methane fuel. Furthermore, the CSSFC exhibits a high peak power density of 215 mW⋅cm-2 with dry methane fuel at 550 °C, which is higher than all reported values of electrolyte-supported SOFCs. This provides a different approach for the development of efficient solid fuel cells.

8.
Nano Lett ; 24(38): 11968-11975, 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39259027

RESUMO

The conversion of woody biomass to H2 through photocatalysis provides a sustainable strategy to generate renewable hydrogen fuel but was limited by the slow decomposition rate of woody biomass. Here, we fabricate ultrasmall TiO2 nanoparticles with tunable concentration of oxygen vacancy defects (VO-TiO2) as highly efficient photocatalysts for photocatalytic conversion of woody biomass to H2. Owing to the positive role of oxygen vacancy in reducing energy barrier for the generation of •OH which was the critical species to oxidize woody biomass, the obtained VO-TiO2 achieves rapid photocatalytic conversion of α-cellulose and poplar wood chip to H2 in the presence of Pt nanoclusters as the cocatalyst. As expected, the highest H2 generation rate in α-cellulose and poplar wood chip system respectively achieve 1146 and 59 µmol h-1 g-1, and an apparent quantum yield of 4.89% at 380 nm was obtained in α-cellulose aqueous solution.

9.
J Am Chem Soc ; 146(31): 22085-22092, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39051463

RESUMO

Azepines and their saturated azepane counterparts are important moieties in bioactive molecules but are under-represented in current drug screening libraries. Herein, we report a mild and efficient azepine formation via silver-catalyzed dearomative nitrene transfer. A 2,2,2-trichloroethoxysulfonyl (Tces)-protected carbamimidate nitrene precursor, coupled with the appropriate ligand for silver, is essential for achieving the unexpected chemoselectivity between arene dearomatization and benzylic C(sp3)-H amination. Potential applications in the late-stage diversification of azepines to complex molecular scaffolds and diastereoselective hydrogenations to sp3-rich derivatives are also highlighted.

10.
Biochem Biophys Res Commun ; 735: 150741, 2024 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-39401480

RESUMO

Diabetes mellitus has been widely acknowledged to have a negative effect on the osteoblastic differentiation of bone marrow-derived mesenchymal stem cells (BMSCs). However, the underlying epigenetic mechanisms associated with this process remain to be elucidated. The goal of the present study was to investigate the effect of diabetes mellitus on the osteoblastic differentiation of BMSCs and assess the role of histone methylation in the observed phenomena. The osteoblastic differentiation ability of BMSCs was shown to be decreased in diabetes mellitus, as indicated by alkaline phosphatase activity and the mRNA levels of osteoblast-related genes. Furthermore, diabetes mellitus caused an increased expression of the histone methylase EZH2 and the levels of H3K27Me3 and decreased the expression of the histone demethylase KDM6B, as demonstrated by qRT-PCR and western blotting. Furthermore, immunofluorescence staining suggested that both EZH2 and H3K27Me3 were primarily localized in the nucleus. In addition, chromatin immunoprecipitation assays indicated an increased presence of H3K27Me3 on the promoter region of the BMP4 gene. In summary, in the present study, we demonstrated that the osteoblastic differentiation of BMSCs is dramatically reduced in diabetes mellitus. In addition, upregulation of EZH2 expression and downregulation of KDM6B expression may not be enough to eliminate transcriptional repression mediated by H3K27Me3 on the promoter region of the BMP4 gene during the osteoblastic differentiation of BMSCs in diabetes mellitus.

11.
Small ; 20(33): e2311684, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38533989

RESUMO

Carbonate-superstructured solid fuel cells (CSSFCs) are an emerging type of fuel cells with high flexibility of fuels. However, using ethane fuel for solid fuel cells is a great challenge due to serious degradation of their anodes. Herein, this critical issue is solved by creating a novel gradient functional layer anode for CSSFCs. First, a finer-scale anode with a larger surface area is demonstrated to provide more active sites for the internal reforming reaction of ethane, achieving a 60% higher ethane conversion rate and 40% lower polarization resistance than conventional anodes. Second, incorporating a gradient functional layer into the anode results in an additional 50% enhancement in the peak power density of CSSFCs to a record high value (up to 241 mW cm-2) with dry ethane fuel at a low temperature of 550 °C, which is even comparable to the power density of conventional solid oxide fuel cells above 700 °C. Furthermore, the CSSFC with the gradient anode exhibits excellent durability for over 200 h. This finding provides a new strategy to develop efficient anodes for hydrocarbon fuels.

12.
J Virol ; 97(2): e0171922, 2023 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-36688655

RESUMO

Coronavirus disease 2019 (COVID-19), which is caused by the novel coronavirus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is the most severe emerging infectious disease in the current century. The discovery of SARS-CoV-2-related coronaviruses (SARSr-CoV-2) in bats and pangolins in South Asian countries indicates that SARS-CoV-2 likely originated from wildlife. To date, two SARSr-CoV-2 strains have been isolated from pangolins seized in Guangxi and Guangdong by the customs agency of China, respectively. However, it remains unclear whether these viruses cause disease in animal models and whether they pose a transmission risk to humans. In this study, we investigated the biological features of a SARSr-CoV-2 strain isolated from a smuggled Malayan pangolin (Manis javanica) captured by the Guangxi customs agency, termed MpCoV-GX, in terms of receptor usage, cell tropism, and pathogenicity in wild-type BALB/c mice, human angiotensin-converting enzyme 2 (ACE2)-transgenic mice, and human ACE2 knock-in mice. We found that MpCoV-GX can utilize ACE2 from humans, pangolins, civets, bats, pigs, and mice for cell entry and infect cell lines derived from humans, monkeys, bats, minks, and pigs. The virus could infect three mouse models but showed limited pathogenicity, with mild peribronchial and perivascular inflammatory cell infiltration observed in lungs. Our results suggest that this SARSr-CoV-2 virus from pangolins has the potential for interspecies infection, but its pathogenicity is mild in mice. Future surveillance among these wildlife hosts of SARSr-CoV-2 is needed to monitor variants that may have higher pathogenicity and higher spillover risk. IMPORTANCE SARS-CoV-2, which likely spilled over from wildlife, is the third highly pathogenic human coronavirus. Being highly transmissible, it is perpetuating a pandemic and continuously posing a severe threat to global public health. Several SARS-CoV-2-related coronaviruses (SARSr-CoV-2) in bats and pangolins have been identified since the SARS-CoV-2 outbreak. It is therefore important to assess their potential of crossing species barriers for better understanding of their risk of future emergence. In this work, we investigated the biological features and pathogenicity of a SARSr-CoV-2 strain isolated from a smuggled Malayan pangolin, named MpCoV-GX. We found that MpCoV-GX can utilize ACE2 from 7 species for cell entry and infect cell lines derived from a variety of mammalian species. MpCoV-GX can infect mice expressing human ACE2 without causing severe disease. These findings suggest the potential of cross-species transmission of MpCoV-GX, and highlight the need of further surveillance of SARSr-CoV-2 in pangolins and other potential animal hosts.


Assuntos
COVID-19 , Especificidade de Hospedeiro , Pangolins , Animais , Humanos , Camundongos , Enzima de Conversão de Angiotensina 2/genética , Linhagem Celular , China , COVID-19/transmissão , COVID-19/virologia , Pulmão/patologia , Pulmão/virologia , Camundongos Transgênicos , Pangolins/virologia , SARS-CoV-2/classificação , SARS-CoV-2/genética , SARS-CoV-2/patogenicidade , Suínos , Quirópteros
13.
Appl Environ Microbiol ; 90(4): e0000724, 2024 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-38501861

RESUMO

With its estrogenic activity, (S)-equol plays an important role in maintaining host health and preventing estrogen-related diseases. Exclusive production occurs through the transformation of soy isoflavones by intestinal bacteria, but the reasons for variations in (S)-equol production among different individuals and species remain unclear. Here, fecal samples from humans, pigs, chickens, mice, and rats were used as research objects. The concentrations of (S)-equol, along with the genetic homology and evolutionary relationships of (S)-equol production-related genes [daidzein reductase (DZNR), daidzein racemase (DDRC), dihydrodaidzein reductase (DHDR), tetrahydrodaidzein reductase (THDR)], were analyzed. Additionally, in vitro functional verification of the newly identified DDRC gene was conducted. It was found that approximately 40% of human samples contained (S)-equol, whereas 100% of samples from other species contained (S)-equol. However, there were significant variations in (S)-equol content among the different species: rats > pigs > chickens > mice > humans. The distributions of the four genes displayed species-specific patterns. High detection rates across various species were exhibited by DHDR, THDR, and DDRC. In contrast, substantial variations in detection rates among different species and individuals were observed with respect to DZNR. It appears that various types of DZNR may be associated with different concentrations of (S)-equol, which potentially correspond to the regulatory role during (S)-equol synthesis. This enhances our understanding of individual variations in (S)-equol production and their connection with functional genes in vitro. Moreover, the newly identified DDRC exhibits higher potential for (S)-equol synthesis compared to the known DDRC, providing valuable resources for advancing in vitro (S)-equol production. IMPORTANCE: (S)-equol ((S)-EQ) plays a crucial role in maintaining human health, along with its known capacity to prevent and treat various diseases, including cardiovascular diseases, metabolic syndromes, osteoporosis, diabetes, brain-related diseases, high blood pressure, hyperlipidemia, obesity, and inflammation. However, factors affecting individual variations in (S)-EQ production and the underlying regulatory mechanisms remain elusive. This study examines the association between functional genes and (S)-EQ production, highlighting a potential correlation between the DZNR gene and (S)-EQ content. Various types of DZNR may be linked to the regulation of (S)-EQ synthesis. Furthermore, the identification of a new DDRC gene offers promising prospects for enhancing in vitro (S)-EQ production.


Assuntos
Equol , Isoflavonas , Animais , Humanos , Camundongos , Ratos , Suínos , Equol/genética , Equol/metabolismo , Racemases e Epimerases , Galinhas/metabolismo , Isoflavonas/metabolismo , Oxirredutases/metabolismo
14.
BMC Microbiol ; 24(1): 433, 2024 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-39455910

RESUMO

BACKGROUND: Diarrheal irritable bowel syndrome (IBS-D) is a functional bowel disease with diarrhea, and can be associated with common spleen deficiency syndrome of the prevelent traditional Chinese medicine (TCM) syndrome. Fecal microbiota transplantation (FMT) could help treating IBS-D, but may provide variable effects. Our study evaluated the efficacy of TCM- shenling Baizhu decoction and FMT in treating IBS-D with spleen deficiency syndrome, with significant implications on gut microbiome and serum metabolites. METHODS: The new borne rats were procured from SPF facility and separated as healthy (1 group) and IBS-D model ( 3 groups) rats were prepared articially using mother's separation and senna leaf treatment. 2 groups of IBS-D models were further treated with TCM- shenling Baizhu decoction and FMT. The efficacy was evaluated by defecation frequency, bristol stool score, and intestinal tight junction proteins (occludin-1 and claudin-1) expression. Microbiomic analysis was conducted using 16 S rRNA sequencing and bioinformatics tools. Metabolomics were detected in sera of rats by LC-MS and annotated by using KEGG database. RESULTS: Significant increment in occludin-1 and claudin-1 protein expression alleviated the diarrheal severity in IBS-D rats (P < 0.05) after treatment with FMT and TCM. FMT and TCM altered the gut microbiota and regulated the tryptophan metabolism, steroid hormone biosynthesis and glycerophospholipid metabolism of IBS-D rats with spleen deficiency syndrome.The microbial abundance were changed in each case e.g., Monoglobus, Dubosiella, and Akkermansia and othe metabolic profiles. CONCLUSION: FMT and TCM treatment improved the intestinal barrier function by regulating gut microbiota and improved metabolic pathways in IBS-D with spleen deficiency syndrome.


Assuntos
Diarreia , Modelos Animais de Doenças , Medicamentos de Ervas Chinesas , Transplante de Microbiota Fecal , Microbioma Gastrointestinal , Síndrome do Intestino Irritável , Medicina Tradicional Chinesa , Metabolômica , Animais , Síndrome do Intestino Irritável/terapia , Síndrome do Intestino Irritável/microbiologia , Síndrome do Intestino Irritável/tratamento farmacológico , Microbioma Gastrointestinal/efeitos dos fármacos , Ratos , Diarreia/microbiologia , Diarreia/terapia , Diarreia/tratamento farmacológico , Medicina Tradicional Chinesa/métodos , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Esplenopatias/terapia , Esplenopatias/microbiologia , Esplenopatias/tratamento farmacológico , Masculino , RNA Ribossômico 16S/genética , Fezes/microbiologia , Baço/microbiologia , Baço/metabolismo
15.
J Org Chem ; 89(7): 4512-4522, 2024 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-38500313

RESUMO

Over the past two decades, the introduction of bioorthogonal reactions has transformed the ways in which chemoselective labeling, isolation, imaging, and drug delivery are carried out in a complex biological milieu. A key feature of a good bioorthogonal probe is the ease with which it can be attached to a target compound through bioconjugation. This paper describes the expansion of the utility of a class of unique S-, N-, and O-containing heterocyclooctynes (SNO-OCTs), which show chemoselective reactivity with type I and type II dipoles and divergent reactivities in response to electronic tuning of the alkyne. Currently, bioconjugation of SNO-OCTs to a desired target is achieved through an inconvenient aryl or amide linker at the sulfamate nitrogen. Herein, a new synthetic approach toward general SNO-OCT scaffolds is demonstrated that enables the installation of functional handles at both propargylic carbons of the heterocycloalkyne. This capability increases the utility of SNO-OCTs as labeling reagents through the design of bifunctional bioorthogonal probes with expanded capabilities. NMR kinetics also revealed up to sixfold improvement in cycloaddition rates of new analogues compared to first-generation SNO-OCTs.


Assuntos
Alcinos , Nitrogênio , Reação de Cicloadição , Alcinos/química , Nitrogênio/química , Indicadores e Reagentes , Amidas
16.
Environ Sci Technol ; 58(23): 10398-10408, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38803193

RESUMO

It is a great challenge to remove VOCs and NOx simultaneously from flue gas in nonelectric industries. This study focuses on the construction of Fe-MnO2 catalysts that perform well in the simultaneous removal of toluene and NOx at low temperatures. Utilizing the Fe-induced phase transition of MnO2, Fe-MnO2-F&R catalysts with a composite morphology of nanoflowers and nanorods were successfully prepared that provided an abundant microporous structure to facilitate the diffusion of molecules of different sizes. Through in-depth investigation of the active sites and reaction mechanism, we discovered that Fe-induced phase transition could modulate the surface acidity of Fe-MnO2-F&R. The higher concentration of surface Mn4+ provided numerous Brønsted acid sites, which effectively promoted the activation of toluene to reactive intermediates, such as benzyl alcohol/benzoate/maleic acid. Simultaneously, Fe provided a large number of Lewis acid sites that anchor and activate NH3 species, thereby inhibiting NH3 nonselective oxidation. Furthermore, additional Brønsted acid sites were generated during the simultaneous reaction process, enhancing toluene activation. Consequently, the simultaneous removal of toluene and NOx was achieved through regulation of the physical structure and the concentration of acidic sites. The present work provides new insights into the rational design of bifunctional catalysts for the synergistic control of VOCs and NOx emissions.


Assuntos
Tolueno , Tolueno/química , Compostos de Manganês/química , Catálise , Óxidos/química , Transição de Fase , Óxidos de Nitrogênio/química , Temperatura Baixa
17.
Environ Sci Technol ; 58(15): 6725-6735, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38565876

RESUMO

It is a promising research direction to develop catalysts with high stability and ozone utilization for low-temperature ozone catalytic oxidation of VOCs. While bimetallic catalysts exhibit excellent catalytic activity compared with conventional single noble metal catalysts, limited success has been achieved in the influence of the bimetallic effect on the stability and ozone utilization of metal catalysts. Herein, it is necessary to systematically study the enhancement effect in the ozone catalytic reaction induced by the second metal. With a simple continuous impregnation method, a platinum-cerium bimetallic catalyst is prepared. Also highlighted are studies from several aspects of the contribution of the second metal (Ce) to the stability and ozone utilization of the catalysts, including the "electronic effect" and "geometric effect". The synergistic removal rate of toluene and ozone is nearly 100% at 30 °C, and it still shows positive stability after high humidity and a long reaction time. More importantly, the instructive significance, which is the in-depth knowledge of enhanced catalytic mechanism of bimetallic catalysts resulting from a second metal, is provided by this work.


Assuntos
Cério , Ozônio , Oxirredução , Metais , Catálise
18.
Int J Med Sci ; 21(10): 1806-1813, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39113891

RESUMO

Background: Roxadustat is commonly used to treat renal anemia. However, the potential effects of roxadustat on metabolism and organs other than the kidneys have recently attracted increased attention. Objective: This study aimed to examine the regulatory effects of roxadustat on thyroid hormones and blood lipid metabolism in patients with end-stage kidney disease (ESKD) undergoing hemodialysis. Methods: Eighty ESKD patients on hemodialysis and taking roxadustat were enrolled. Hemoglobin, thyroid hormones (TSH, FT3, FT4), and blood lipid profiles (TC, LDL-C, TG, HDL-C) were assessed before and after treatment. Changes in these parameters were compared, and relevant causative factors were analyzed. Results: Roxadustat significantly increased Hb, lowered TSH, FT4, TC, and LDL-C levels (all P<0.001). Patients were categorized into three groups based on post-treatment TSH inhibition percentage: Q1(≥70%), Q2(30%-70%), Q3(≤30%). Pre-treatment TSH decreased with reduced TSH inhibition (P<0.05). Post-treatment, TC, LDL-C, TSH, FT3, and FT4 increased with reduced TSH inhibition (all P<0.05).TC and LDL-C significantly decreased post-treatment in Q1 and Q2 (P<0.05). Correlation analysis showed a positive correlation between ΔTSH and pre-treatment TSH levels (r=0.732, P<0.001). The proportion of patients with ≥70% TSH inhibition increased with higher pre-treatment TSH levels (P for trend <0.05). ΔLDL-C and ΔTSH were positively correlated (r=0.278, P<0.05), with ΔTSH identified as an influencing factor in multiple linear regression (ß=0.133, 95% CI [0.042, 0.223], P<0.05). Conclusion: Roxadustat effectively improves anemia in ESKD patients while inhibiting TSH and FT4 secretion and reducing TC and LDL-C levels. Decreases in TSH levels correlate with baseline TSH levels, and lowered blood lipid levels are associated with decreased TSH levels.


Assuntos
Glicina , Isoquinolinas , Falência Renal Crônica , Metabolismo dos Lipídeos , Diálise Renal , Hormônios Tireóideos , Humanos , Masculino , Feminino , Diálise Renal/efeitos adversos , Pessoa de Meia-Idade , Estudos Retrospectivos , Falência Renal Crônica/terapia , Falência Renal Crônica/sangue , Falência Renal Crônica/complicações , Idoso , Glicina/análogos & derivados , Glicina/uso terapêutico , Metabolismo dos Lipídeos/efeitos dos fármacos , Hormônios Tireóideos/sangue , Isoquinolinas/uso terapêutico , Isoquinolinas/administração & dosagem , Lipídeos/sangue , Adulto , Tireotropina/sangue
19.
J Nanobiotechnology ; 22(1): 597, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39354474

RESUMO

Recent findings suggest that immunoradiotherapy (IRT), combining photon radiotherapy (XRT) or proton radiotherapy (PRT) with immune checkpoint blockade, can enhance systemic tumor control. However, the comparative efficacy of XRT and PRT in IRT remains understudied. To address this, we compared outcomes between XRT + αPD1 and PRT + αPD1 in murine αPD1-resistant lung cancer (344SQR). We also assessed the impact of the nanoparticle radioenhancer NBTXR3 on both XRT + αPD1 and PRT + αPD1 for tumor control and examined the tumor immune microenvironment using single-cell RNA sequencing (scRNAseq). Additionally, mice cured by NBTXR3 + PRT + αPD1 were rechallenged with three lung cancer cell lines to evaluate memory antitumor immunity. PRT + αPD1 showed superior local tumor control and abscopal effects compared to XRT + αPD1. NBTXR3 + PRT + αPD1 significantly outperformed NBTXR3 + XRT + αPD1 in tumor control, promoting greater infiltration of antitumor lymphocytes into irradiated tumors. Unirradiated tumors treated with NBTXR3 + PRT + αPD1 had more NKT cells, CD4 T cells, and B cells, with fewer Tregs, than those treated with NBTXR3 + XRT + αPD1. NBTXR3 + PRT + αPD1 also stimulated higher expression of IFN-γ, GzmB, and Nkg7 in lymphocytes, reduced the TGF-ß pathway, and increased tumor necrosis factor alpha expression compared to NBTXR3 + XRT + αPD1. Moreover, NBTXR3 + PRT + αPD1 resulted in greater M1 macrophage polarization in both irradiated and unirradiated tumors. Mice achieving remission through NBTXR3 + PRT + αPD1 exhibited a robust memory immune response, effectively inhibiting growth of subsequent tumors from three distinct lung cancer cell lines. Proton IRT combined with NBTXR3 offers enhanced tumor control and survival rates over photon-based treatments in managing αPD1-resistant lung cancer, indicating its potential as a potent systemic therapy.


Assuntos
Neoplasias Pulmonares , Terapia com Prótons , Microambiente Tumoral , Animais , Camundongos , Linhagem Celular Tumoral , Microambiente Tumoral/efeitos dos fármacos , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/terapia , Neoplasias Pulmonares/imunologia , Terapia com Prótons/métodos , Fótons , Nanopartículas/química , Feminino , Radioimunoterapia/métodos , Radiossensibilizantes/farmacologia , Humanos
20.
Nucleic Acids Res ; 50(11): 6423-6434, 2022 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-35687127

RESUMO

Prime editors consisting of Cas9-nickase and reverse transcriptase enable targeted precise editing of small DNA pieces, including all 12 kinds of base substitutions, insertions and deletions, while without requiring double-strand breaks or donor templates. Current optimized prime editing strategy (PE3) uses two guide RNAs to guide the performance of prime editor. One guide RNA carrying both spacer and templating sequences (pegRNA) guides prime editor to produce ssDNA break and subsequent extension, and the other one produces a nick in the complementary strand. Here, we demonstrated that positioning the nick sgRNA nearby the templating sequences of the pegRNA facilitated targeted large fragment deletion and that engineering both guide RNAs to be pegRNAs to achieve bi-direction prime editing (Bi-PE) further increase the efficiency by up to 16 times and improved the accuracy of editing products by 60 times. In addition, we showed that Bi-PE strategy also increased the efficiency of simultaneous conversion of multiple bases but not single base conversion over PE3. In conclusion, Bi-PE strategy expanded the editing scope and improved the efficiency and the accuracy of prime editing system, which might have a wide range of potential applications.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes , Pequeno RNA não Traduzido , Animais , Sistemas CRISPR-Cas/genética , Desoxirribonuclease I/metabolismo , Quebras de DNA de Cadeia Dupla , Mamíferos/genética , DNA Polimerase Dirigida por RNA/metabolismo , Pequeno RNA não Traduzido/genética
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