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1.
Am J Physiol Cell Physiol ; 326(1): C27-C39, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37661919

RESUMO

The follicle is the basic structural and functional unit of the ovary in female mammals. The excessive depletion of follicles will lead to diminished ovarian reserve or even premature ovarian failure, resulting in diminished ovarian oogenesis and endocrine function. Excessive follicular depletion is mainly due to loss of primordial follicles. Our analysis of published human ovarian single-cell sequencing results by others revealed a significant increase in rho-associated protein kinase 1 (ROCK1) expression during primordial follicle development. However, the role of ROCK1 in primordial follicle development and maintenance is not clear. This study revealed a gradual increase in ROCK1 expression during primordial follicle activation. Inhibition of ROCK1 resulted in reduced primordial follicle activation, decreased follicular reserve, and delayed development of growing follicles. This effect may be achieved through the HIPPO pathway. The present study indicates that ROCK1 is a key molecule for primordial follicular reserve and follicular development.NEW & NOTEWORTHY ROCK1, one of the Rho GTPases, plays an important role in primordial follicle reserve and follicular development. ROCK1 was primarily expressed in the cytoplasm of oocytes and granulosa cell in mice. Inhibition of ROCK1 significantly reduced the primordial follicle reserve and delayed growing follicle development. ROCK1 regulates primordial follicular reserve and follicle development through the HIPPO signaling pathway. These findings shed new lights on the physiology of sustaining female reproduction.


Assuntos
Oócitos , Folículo Ovariano , Animais , Feminino , Humanos , Camundongos , Células da Granulosa/metabolismo , Mamíferos , Oogênese , Folículo Ovariano/metabolismo , Ovário/metabolismo , Quinases Associadas a rho/genética , Quinases Associadas a rho/metabolismo
2.
Biochem Biophys Res Commun ; 717: 150061, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38718570

RESUMO

Epithelial mesenchymal transition (EMT) is a critical process implicated in the pathogenesis of retinal fibrosis and the exacerbation of diabetic retinopathy (DR) within retinal pigment epithelium (RPE) cells. Apigenin (AP), a potential dietary supplement for managing diabetes and its associated complications, has demonstrated inhibitory effects on EMT in various diseases. However, the specific impact and underlying mechanisms of AP on EMT in RPE cells remain poorly understood. In this study, we have successfully validated the inhibitory effects of AP on high glucose-induced EMT in ARPE-19 cells and diabetic db/db mice. Notably, our findings have identified CBP/p300 as a potential therapeutic target for EMT in RPE cells and have further substantiated that AP effectively downregulates the expression of EMT-related genes by attenuating the activity of CBP/p300, consequently reducing histone acetylation alterations within the promoter region of these genes. Taken together, our results provide novel evidence supporting the inhibitory effect of AP on EMT in RPE cells, and highlight the potential of specifically targeting CBP/p300 as a strategy for inhibiting retinal fibrosis in the context of DR.


Assuntos
Apigenina , Transição Epitelial-Mesenquimal , Glucose , Histonas , Epitélio Pigmentado da Retina , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Epitélio Pigmentado da Retina/efeitos dos fármacos , Epitélio Pigmentado da Retina/metabolismo , Epitélio Pigmentado da Retina/patologia , Animais , Apigenina/farmacologia , Acetilação/efeitos dos fármacos , Humanos , Glucose/metabolismo , Glucose/toxicidade , Histonas/metabolismo , Linhagem Celular , Camundongos , Fatores de Transcrição de p300-CBP/metabolismo , Fatores de Transcrição de p300-CBP/antagonistas & inibidores , Camundongos Endogâmicos C57BL , Retinopatia Diabética/metabolismo , Retinopatia Diabética/patologia , Retinopatia Diabética/tratamento farmacológico , Proteína p300 Associada a E1A/metabolismo , Masculino , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Proteína de Ligação a CREB/metabolismo , Proteína de Ligação a CREB/genética
3.
Small ; 20(22): e2307853, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38143294

RESUMO

Converting carbon dioxide (CO2) into fuel and high-value-added chemicals is considered a green and effective way to solve global energy and environmental problems. Covalent triazine frameworks (CTFs) are extensively utilized as an emerging catalyst for photo/electrocatalytic CO2 reduction reaction (CO2RR) recently recognized for their distinctive qualities, including excellent thermal and chemical stability, π-conjugated structure, rich nitrogen content, and a strong affinity for CO2, etc. Nevertheless, single-component CTFs have the problems of accelerated recombination of photoexcited electron-hole pairs and restricted conductivity, which limit their application for photo/electrocatalytic CO2RR. Therefore, emphasis will then summarize the strategies for enhancing the photocatalytic and electrocatalytic efficiency of CTFs for CO2RR in this paper, including atom doping, constructing a heterojunction structure, etc. This review first illustrates the synthesis strategies of CTFs and the advantages of CTFs in the field of photo/electrocatalytic CO2RR. Subsequently, the mechanism of CTF-based materials in photo/electrocatalytic CO2RR is described. Lastly, the challenges and future prospects of CTFs in photo/electrocatalytic CO2RR are addressed, which offers a fresh perspective for the future development of CTFs in photo/electrocatalytic CO2RR.

4.
Small ; 20(7): e2306621, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37814375

RESUMO

Future renewable energy supply and green, sustainable environmental development rely on various types of catalytic reactions. Copper single-atom catalysts (Cu SACs) are attractive due to their distinctive electronic structure (3d orbitals are not filled with valence electrons), high atomic utilization, and excellent catalytic performance and selectivity. Despite numerous optimization studies are conducted on Cu SACs in terms of energy conversion and environmental purification, the coupling among Cu atoms-support interactions, active sites, and catalytic performance remains unclear, and a systematic review of Cu SACs is lacking. To this end, this work summarizes the recent advances of Cu SACs. The synthesis strategies of Cu SACs, metal-support interactions between Cu single atoms and different supports, modification methods including modification for carriers, coordination environment regulating, site distance effect utilizing, and dual metal active center catalysts constructing, as well as their applications in energy conversion and environmental purification are emphatically introduced. Finally, the opportunities and challenges for the future Cu SACs development are discussed. This review aims to provide insight into Cu SACs and a reference for their optimal design and wide application.

5.
Plant Biotechnol J ; 22(1): 66-81, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38153293

RESUMO

Rye (Secale cereale), a valuable relative of wheat, contains abundant powdery mildew resistance (Pm) genes. Using physical mapping, transcriptome sequencing, barley stripe mosaic virus-induced gene silencing, ethyl methane sulfonate mutagenesis, and stable transformation, we isolated and validated two coiled-coil, nucleotide-binding site and leucine-rich repeat (CC-NBS-LRR) alleles, PmTR1 and PmTR3, located on rye chromosome 6RS from different triticale lines. PmTR1 confers age-related resistance starting from the three-leaf stage, whereas its allele, PmTR3, confers typical all-stage resistance, which may be associated with their differential gene expression patterns. Overexpression in Nicotiana benthamiana showed that the CC, CC-NBS, and CC-LRR fragments of PMTR1 induce cell death, whereas in PMTR3 the CC and full-length fragments perform this function. Luciferase complementation imaging and pull-down assays revealed distinct interaction activities between the CC and NBS fragments. Our study elucidates two novel rye-derived Pm genes and their derivative germplasm resources and provides novel insights into the mechanism of age-related resistance, which can aid the improvement of resistance against wheat powdery mildew.


Assuntos
Ascomicetos , Secale , Secale/genética , Resistência à Doença/genética , Triticum/genética , Proteínas de Repetições Ricas em Leucina , Ascomicetos/fisiologia , Nucleotídeos , Cromossomos de Plantas/genética , Sítios de Ligação , Doenças das Plantas/genética
6.
J Virol ; 97(10): e0106323, 2023 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-37732788

RESUMO

IMPORTANCE: Porcine epidemic diarrhea (PED) caused by PED virus (PEDV) remains a big threat to the swine industry worldwide. Vaccination with live attenuated vaccine is a promising method to prevent and control PED, because it can elicit a more protective immunity than the killed vaccine, subunit vaccine, and so on. In this study, we found two obvious deletions in the genome of a high passage of AH2012/12. We further confirmed the second deletion which contains seven amino acids at the carboxy-terminus of the S2 gene and the start codon of ORF3 can reduce its pathogenicity in vivo. Animal experiments indicated that the recombinant PEDV with deleted carboxy-terminus of S gene showed higher IgG, IgA, neutralization antibodies, and protection effects against virus challenge than the killed vaccine. These data reveal that the engineering of the carboxy-terminus of the S2 gene may be a promising method to develop live attenuated vaccine candidates of PEDV.


Assuntos
Infecções por Coronavirus , Vírus da Diarreia Epidêmica Suína , Doenças dos Suínos , Animais , Infecções por Coronavirus/veterinária , Infecções por Coronavirus/virologia , Diarreia , Vírus da Diarreia Epidêmica Suína/genética , Vírus da Diarreia Epidêmica Suína/patogenicidade , Suínos , Doenças dos Suínos/virologia , Vacinas Atenuadas/genética , Vacinas de Produtos Inativados , Vacinas Virais/genética , Virulência
7.
Opt Express ; 32(6): 10461-10478, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38571257

RESUMO

We propose a multimode interference-based optical fiber NHTSN sensor with a helical taper for simultaneous measurement of micro torsion and temperature. The sensor consists of single mode fiber (SMF), no-core fiber (NCF), and seven-core fiber (SCF). A helical taper is fabricated in the SCF using a flame heater, forming the SMF-NCF-Helical Taper SCF-NCF-SMF (NHTSN) structure. Theoretical analysis and experimental results demonstrate that the introduction of helical taper not only imparts directionality to the torsion measurement, but also results in a significant improvement in torsion sensitivity due to the increased inter-mode optical path difference (OPD) and enhanced inter-mode coupling. In the experiment, the torsion sensitivity of the NHTSN sensor reaches -1.255 nm/(rad/m) in the twist rate (TR) range of -3.931 rad/m to 3.931 rad/m, which is a 9-fold improvement over the original structure. Further reduction of the helical taper diameter increases the sensitivity to -1.690 nm/(rad/m). In addition, the sensor has a temperature sensitivity of up to 97 pm/°C from 20 °C to 90 °C, and simultaneous measurement of torsion and temperature is attainable through a dual-parameter measurement matrix. The NHTSN sensor possesses advantages of compact size, high sensitivity, good linearity, and strain-independence, endowing it with potential applications in structural health monitoring (SHM) and engineering machinery.

8.
Psychol Med ; 54(4): 775-784, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37671675

RESUMO

BACKGROUND: The neuroanatomical alteration in bipolar II depression (BDII-D) and its associations with inflammation, childhood adversity, and psychiatric symptoms are currently unclear. We hypothesize that neuroanatomical deficits will be related to higher inflammation, greater childhood adversity, and worse psychiatric symptoms in BDII-D. METHODS: Voxel- and surface-based morphometry was performed using the CAT toolbox in 150 BDII-D patients and 155 healthy controls (HCs). Partial Pearson correlations followed by multiple comparison correction was used to indicate significant relationships between neuroanatomy and inflammation, childhood adversity, and psychiatric symptoms. RESULTS: Compared with HCs, the BDII-D group demonstrated significantly smaller gray matter volumes (GMVs) in frontostriatal and fronto-cerebellar area, insula, rectus, and temporal gyrus, while significantly thinner cortices were found in frontal and temporal areas. In BDII-D, smaller GMV in the right middle frontal gyrus (MFG) was correlated with greater sexual abuse (r = -0.348, q < 0.001) while larger GMV in the right orbital MFG was correlated with greater physical neglect (r = 0.254, q = 0.03). Higher WBC count (r = -0.227, q = 0.015) and IL-6 levels (r = -0.266, q = 0.015) was associated with smaller GMVs in fronto-cerebellar area in BDII-D. Greater positive symptoms was correlated with larger GMVs of the left middle temporal pole (r = 0.245, q = 0.03). CONCLUSIONS: Neuroanatomical alterations in frontostriatal and fronto-cerebellar area, insula, rectus, temporal gyrus volumes, and frontal-temporal thickness may reflect a core pathophysiological mechanism of BDII-D, which are related to inflammation, trauma, and psychiatric symptoms in BDII-D.


Assuntos
Experiências Adversas da Infância , Transtorno Bipolar , Humanos , Transtorno Bipolar/diagnóstico por imagem , Depressão/diagnóstico por imagem , Imageamento por Ressonância Magnética , Encéfalo/diagnóstico por imagem , Substância Cinzenta/diagnóstico por imagem , Inflamação/diagnóstico por imagem
9.
Immunity ; 43(2): 251-63, 2015 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-26275994

RESUMO

Regulatory T (Treg) cells are essential for maintenance of immune homeostasis. Here we found that hydrogen sulfide (H2S) was required for Foxp3(+) Treg cell differentiation and function and that H2S deficiency led to systemic autoimmune disease. H2S maintained expression of methylcytosine dioxygenases Tet1 and Tet2 by sulfhydrating nuclear transcription factor Y subunit beta (NFYB) to facilitate its binding to Tet1 and Tet2 promoters. Transforming growth factor-ß (TGF-ß)-activated Smad3 and interleukin-2 (IL-2)-activated Stat5 facilitated Tet1 and Tet2 binding to Foxp3. Tet1 and Tet2 catalyzed conversion of 5-methylcytosine (5mC) to 5-hydroxymethylcytosine (5hmC) in Foxp3 to establish a Treg-cell-specific hypomethylation pattern and stable Foxp3 expression. Consequently, Tet1 and Tet2 deletion led to Foxp3 hypermethylation, impaired Treg cell differentiation and function, and autoimmune disease. Thus, H2S promotes Tet1 and Tet2 expression, which are recruited to Foxp3 by TGF-ß and IL-2 signaling to maintain Foxp3 demethylation and Treg-cell-associated immune homeostasis.


Assuntos
Colite/imunologia , Proteínas de Ligação a DNA/metabolismo , Fatores de Transcrição Forkhead/metabolismo , Sulfeto de Hidrogênio/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Linfócitos T Reguladores/imunologia , Transferência Adotiva , Animais , Fator de Ligação a CCAAT/metabolismo , Diferenciação Celular/genética , Colite/genética , Metilação de DNA/genética , Proteínas de Ligação a DNA/genética , Dioxigenases , Fatores de Transcrição Forkhead/genética , Homeostase/genética , Homeostase/imunologia , Humanos , Interleucina-2/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Proto-Oncogênicas/genética , Fator de Transcrição STAT5/metabolismo , Proteína Smad3/metabolismo , Linfócitos T Reguladores/transplante , Fator de Crescimento Transformador beta/imunologia
10.
Soft Matter ; 20(21): 4246-4256, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38747973

RESUMO

The self-oscillation of objects that perform continuous and periodic motions upon unchanging and constant stimuli is highly important for intelligent actuators, advanced robotics, and biomedical machines. Liquid crystalline elastomer (LCE) materials are superior to traditional stimuli-responsive polymeric materials in the development of self-oscillators because of their reversible, large and anisotropic shape-changing ability, fast response ability and versatile structural design. In addition, fiber-shaped oscillators have attracted much interest due to their agility, flexibility and diverse oscillation modes. Herein, we present a strategy for fabricating fiber-shaped LCE self-oscillators using soft tubes as molds. Through the settlement of different configuration states of the soft tubes, the prepared fiber-shaped LCE oscillators can perform continuous rotational self-oscillation or up-and-down shifting self-oscillation under constant light stimuli, which are realized by photoinduced repetitive self-winding motion and self-waving motion, respectively. The mechanism of self-oscillating movements is attributed to the local temperature oscillation of LCE fibers caused by repetitive self-shadowing effects. LCE self-oscillators can operate stably over many oscillating cycles without obvious performance attenuation, revealing good robustness. Our work offers a versatile way by which LCE self-oscillators can be conveniently designed and fabricated in bulk and at low cost, and broadens the road for developing self-oscillating materials for biological robotics and health care machines.

11.
Med Sci Monit ; 30: e943666, 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38850016

RESUMO

BACKGROUND Helicobacter pylori has a high infection rate worldwide, and epidemiological study of H. pylori is important. Artificial intelligence has been widely used in the field of medical research and has become a hotspot in recent years. This paper proposed a prediction model for H. pylori infection based on machine learning in adults. MATERIAL AND METHODS Adult patients were selected as research participants, and information on 30 factors was collected. The chi-square test, mutual information, ReliefF, and information gain were used to screen the feature factors and establish 2 subsets. We constructed an H. pylori infection prediction model based on XGBoost and optimized the model using a grid search by analyzing the correlation between features. The performance of the model was assessed by comparing its accuracy, recall, precision, F1 score, and AUC with those of 4 other classical machine learning methods. RESULTS The model performed better on the part B subset than on the part A subset. Compared with the other 4 machine learning methods, the model had the highest accuracy, recall, F1 score, and AUC. SHAP was used to evaluate the importance of features in the model. It was found that H. pylori infection of family members, living in rural areas, poor washing hands before meals and after using the toilet were risk factors for H. pylori infection. CONCLUSIONS The model proposed in this paper is superior to other models in predicting H. pylori infection and can provide a scientific basis for identifying the population susceptible to H. pylori and preventing H. pylori infection.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Aprendizado de Máquina , Humanos , Infecções por Helicobacter/diagnóstico , Infecções por Helicobacter/epidemiologia , Adulto , Masculino , Feminino , Pessoa de Meia-Idade , Fatores de Risco
12.
Biol Res ; 57(1): 3, 2024 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-38217055

RESUMO

BACKGROUND: Sensorineural hearing loss (SNHL) poses a major threat to both physical and mental health; however, there is still a lack of effective drugs to treat the disease. Recently, novel biological therapies, such as mesenchymal stem cells (MSCs) and their products, namely, exosomes, are showing promising therapeutic potential due to their low immunogenicity, few ethical concerns, and easy accessibility. Nevertheless, the precise mechanisms underlying the therapeutic effects of MSC-derived exosomes remain unclear. RESULTS: Exosomes derived from MSCs reduced hearing and hair cell loss caused by neomycin-induced damage in models in vivo and in vitro. In addition, MSC-derived exosomes modulated autophagy in hair cells to exert a protective effect. Mechanistically, exogenously administered exosomes were internalized by hair cells and subsequently upregulated endocytic gene expression and endosome formation, ultimately leading to autophagy activation. This increased autophagic activity promoted cell survival, decreased the mitochondrial oxidative stress level and the apoptosis rate in hair cells, and ameliorated neomycin-induced ototoxicity. CONCLUSIONS: In summary, our findings reveal the otoprotective capacity of exogenous exosome-mediated autophagy activation in hair cells in an endocytosis-dependent manner, suggesting possibilities for deafness treatment.


Assuntos
Exossomos , Neomicina , Neomicina/toxicidade , Neomicina/metabolismo , Exossomos/metabolismo , Células Ciliadas Auditivas , Autofagia/fisiologia
13.
Sensors (Basel) ; 24(11)2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38894241

RESUMO

Eddy current testing (ECT) is commonly used for the detection of defects inside metallic materials. In order to achieve the effective testing of CFRP materials, increasing the operating frequency or improving the coil structure is a common method used by researchers. Higher or wider operating frequencies make the design of the ADC's conditioning circuit complex and difficult to miniaturize. In this paper, an LC resonator based on inductance-to-digital converters (LDCs) is designed to easily detect the resonant frequency response to the state of the material under test. The reasonableness of the coil design is proven by simulation. The high signal-to-noise ratio (SNR) and detection sensitivity of the LC resonator are demonstrated through comparison experiments involving multiple probes. The anti-interference capability of the LC resonator in CFRP defect detection is demonstrated through various interference experiments.

14.
J Environ Sci (China) ; 138: 470-481, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38135413

RESUMO

The close-coupled selective catalytic reduction (cc-SCR) catalyst is an effective technology to reduce tailpipe NOx emission during cold start. This paper investigated the optimal ammonia storage under steady and transient state in the cc-SCR. The study showed that a trade-off between NOx conversion efficiency and ammonia slip is observed on the pareto solutions under steady state, and the optimal ammonia storage is calculated with ammonia slip less than 10 µL/L based on the China Ⅵ emission legislation. The rapid temperature increase will lead to severe ammonia slip in the transient test cycle. A simplified 0-D calculation method on ammonia slip under transient state is proposed based on kinetic model of ammonia adsorption and desorption. In addition, the effect of ammonia storage, catalyst temperature and temperature increasing rate on ammonia slip are analyzed. The optimal ammonia storage is calculated with maximum ammonia slip less than 100 µL/L according to the oxidation efficiency of ammonia slip catalyst (ASC) downstream cc-SCR. It was found that the optimal ammonia storage under transient state is much lower than that under steady state in cc-SCR at lower temperature, and a phase diagram is established to analyze the influence of temperature and temperature increasing rate on optimal ammonia storage.


Assuntos
Amônia , Temperatura Baixa , Oxirredução , Temperatura , Catálise
15.
BMC Genomics ; 24(1): 354, 2023 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-37365511

RESUMO

BBX proteins play important roles in all of the major light-regulated developmental processes. However, no systematic analysis of BBX gene family regarding the regulation of photoperiodic microtuber formation has been previously performed in yam. In this study, a systematic analysis on the BBX gene family was conducted in three yam species, with the results, indicating that this gene plays a role in regulating photoperiodic microtuber formation. These analyses included identification the BBX gene family in three yam species, their evolutionary relationships, conserved domains, motifs, gene structure, cis-acting elements, and expressional patterns. Based on these analyses, DoBBX2/DoCOL5 and DoBBX8/DoCOL8 showing the most opposite pattern of expression during microtuber formation were selected as candidate genes for further investigation. Gene expression analysis showed DoBBX2/DoCOL5 and DoBBX8/DoCOL8 were highest expressed in leaves and exhibited photoperiod responsive expression patterns. Besides, the overexpression of DoBBX2/DoCOL5 and DoBBX8/DoCOL8 in potato accelerated tuber formation under short-day (SD) conditions, whereas only the overexpression of DoBBX8/DoCOL8 enhanced the accelerating effect of dark conditions on tuber induction. Tuber number was increased in DoBBX8/DoCOL8 overexpressing plants under dark, as well as in DoBBX2/DoCOL5 overexpressing plants under SD. Overall, the data generated in this study may form the basis of future functional characterizations of BBX genes in yam, especially regarding their regulation of microtuber formation via the photoperiodic response pathway.


Assuntos
Dioscorea , Dioscorea/genética , Dioscorea/metabolismo , Perfilação da Expressão Gênica , Família Multigênica , Fotoperíodo , Ritmo Circadiano , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/metabolismo
16.
J Am Chem Soc ; 145(9): 5310-5319, 2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36758639

RESUMO

Herein, we report a versatile solvent-mediated polymerization-induced self-assembly (PISA) strategy to directly synthesize highly N-doped hierarchically porous structured carbon spheres with a tunable meso-macroporous configuration. The introduction of intermolecular hydrogen bonds is verified to enhance the interfacial interactions between block copolymers, oil droplets, and polyphenols. Moreover, the dominant hydrogen-bond-driven interactions can be systematically manipulated by selecting different cosolvent systems to generate diverse porous structures from the transformation of micellar and precursor co-assembly. Impressively, hierarchically structured meso-macroporous N-doped carbon spheres present simultaneously tunable sphere sizes and mesopores and macropores, ranging from 1.2 µm, 9/50 and 227 nm to 1.0 µm, 40, and 183 nm and 480, 24, and 95 nm. As a demonstration, dendritic-like N-doped hierarchically meso-macroporous carbon spheres manifest excellent enzyme-like activity, which is attributed to the continuous mass transport from the multiordered porosity. The current study provides a new platform for the synthesis of novel well-defined porous materials.

17.
Anal Chem ; 95(28): 10557-10564, 2023 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-37387220

RESUMO

Cobalt-mediated radical polymerization is noted for its great level of control over the polymerization of acrylic and vinyl esters monomers, even at high molar mass. Vitamin B12, a natural bionic enzyme cobalt complex, involves the conversion of organic halides to olefins through chain-growth polymerization. In this work, the notion of R-Co(III) free radical persistent free radical effect and vitamin B12 circulation were first reported for the perception of ultralow abundance of microRNA-21, a lung cancer biomarker. Indeed, most Co-containing catalytic reactions can occur under mild conditions due to their minimal bond dissociation of the C-Co bond, with blue light irradiation. Based on the intrinsic stability of the vitamin B12 framework and recycling of the catalyst, it is evident that this natural catalytic scheme has potential applications in medicinal chemistry and biomaterials. In addition, this strategy, combined with highly specific recognition probes and vitamin B12 circulation-mediated chain-growth polymerization, has a detection limit as low as 910 aM. Furthermore, it is sensitive for sensing in serum samples containing biomarkers and shows great potential for RNA selection and amplification sensing in clinical samples.


Assuntos
Biomarcadores Tumorais , Neoplasias Pulmonares , Humanos , Polimerização , Biônica , Vitamina B 12 , Radicais Livres/química , Cobalto/química , Complexos Multienzimáticos , Pulmão , Vitaminas
18.
Small ; 19(50): e2304808, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37501314

RESUMO

The synthesis of efficient and highly selective catalysts and rational reactor design play decisive roles in the industrial application of the electrocatalytic carbon dioxide reduction reaction (CO2 RR). In this study, a dual-metal-organic framework (MOF) copper-based catalytic electrode is designed and prepared in one step by in situ synthesis on a foamed copper substrate. The MOF-on-MOF structure can effectively inhibit the generation of H2 and CO, and further enhance the selectivity of HCOOH. Furthermore, by using cheap and durable poly(tetrafluoroethylene) (PTFE) instead of an expensive and fragile GDE, the optimized reactor design improves the stability and durability of the gas channel and the replaceability of the electrode. The structure-optimized reactor has a maximum Faradaic efficiency of 89.2% in neutral medium, and an average current density of 26.1 mA cm-2 in the flow cell, which has comparable performance to a GDE and can continue to operate stably. The use of PTFE improves the service life of the gas mass transfer channel, and the independent catalytic electrode can provide good catalytic efficiency. These results provide new insights into the reaction mechanism of structurally recombined double MOFs and PTFE-optimized CO2 RR reactor designs, providing technical support for the practical industrial application of the CO2 RR.

19.
Small ; 19(34): e2301817, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37093465

RESUMO

Single-atom catalysts (SACs) for photocatalytic hydrogen peroxide (H2 O2 ) generation are researched but it is still challenging to obtain high H2 O2 yields. Herein, graphite carbon nitride (FeSA /CN) confined single Fe atoms with N/O coordination is prepared, and FeSA /CN shows high H2 O2 production via oxalic acid and O2 activation. Under visible light illumination, the concentration of H2 O2 generated by FeSA /CN can achieve 40.19 mM g-1 h-1 , which is 10.44 times higher than that of g-C3 N4 . The enhanced H2 O2 generation can be attributed to the formation of metal-organic complexes and rapid electron transfer. Moreover, the O2 activation of photocatalysts is revealed by 3,3',5,5'-tetramethylbenzidine oxidation. The results display that the O2 activation capacity of FeSA /CN is higher than that of g-C3 N4 , which facilitates the formation of H2 O2 . Finally, density functional theory calculation demonstrates that O2 is chemically adsorbed on Fe atomic sites. The adsorption energy of O2 is enhanced from -0.555 to -1.497 eV, and the bond length of OO is extended from 1.235 to 1.292 Å. These results exhibit that the confinement of single Fe atoms can promote O2 adsorption and activation. Finally, the photocatalytic mechanism is elaborated, which provides a deep understanding for SACs-catalyzed H2 O2 generation.

20.
Pancreatology ; 23(1): 18-27, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36503677

RESUMO

BACKGROUND: Measuring intra-abdominal pressure (IAP) is important for management of patients with severe acute pancreatitis (SAP). Intra-bladder pressure (IBP) is an indirect index that reflects IAP, but measuring techniques vary. We sought to optimise IBP measuring techniques in predicted SAP patients. METHODS: Predicted SAP patients consecutively admitted between June 2018 and January 2020 were scrutinised. Eligible patients had their IBP monitored for the first 72 h at 6-h intervals, and were then sequentially allocated into three research scenarios: (1) in the supine position along with head of bed elevation(HoBE)of 0, 15 and 30° at various points including the iliac crest the midaxillary line, pubic symphysis, and right atrium level, instilled with 25 mL normal saline (NS) at room temperature (RT); (2) NS instillation volume from 0, 10, 25, 40-50 mL at the iliac crest with HoBE15 at RT; and (3) NS instillation (25 mL) at either RT or 37 °C with HoBE15. RESULTS: The dynamic IBP values measured at the pubic symphysis and iliac crest were fairly similar between HoBE0 and HoBE15 (all P > 0.05), but greatly increased at HoBE30 (all P < 0.01). IBP was significantly increased with escalating instillation volumes of NS (all P < 0.01 versus 0 mL NS), while there was no significant difference between 25 mL and 10 mL (P = 0.055). IBP was similar between NS at RT and under 37 °C (P = 0.643). CONCLUSION: In predicted SAP patients, measuring IBP at the iliac crest with HoBE15 after instilling 10 mL of NS seems to be appropriate for monitoring IAP.


Assuntos
Pancreatite , Humanos , Bexiga Urinária , Doença Aguda , Pressão , Solução Salina
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