Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 140
Filtrar
1.
FASEB J ; 38(13): e23706, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38877842

RESUMO

The etiology of preeclampsia (PE), a complex and multifactorial condition, remains incompletely understood. DNA methylation, which is primarily regulated by three DNA methyltransferases (DNMTs), DNMT1, DNMT3A, and DNMT3B, plays a vital role in early embryonic development and trophectoderm differentiation. Yet, how DNMTs modulate trophoblast fusion and PE development remains unclear. In this study, we found that the DNMTs expression was downregulated during trophoblast cells fusion. Downregulation of DNMTs was observed during the reconstruction of the denuded syncytiotrophoblast (STB) layer of placental explants. Additionally, overexpression of DNMTs inhibited trophoblast fusion. Conversely, treatment with the DNA methylation inhibitor 5-aza-CdR decreased the expression of DNMTs and promoted trophoblast fusion. A combined analysis of DNA methylation data and gene transcriptome data obtained from the primary cytotrophoblasts (CTBs) fusion process identified 104 potential methylation-regulated differentially expressed genes (MeDEGs) with upregulated expression due to DNA demethylation, including CD59, TNFAIP3, SDC1, and CDK6. The transcription regulation region (TRR) of TNFAIP3 showed a hypomethylation with induction of 5-aza-CdR, which facilitated CREB recruitment and thereby participated in regulating trophoblast fusion. More importantly, clinical correlation analysis of PE showed that the abnormal increase in DNMTs may be involved in the development of PE. This study identified placental DNA methylation-regulated genes that may contribute to PE, offering a novel perspective on the role of epigenetics in trophoblast fusion and its implication in PE development.


Assuntos
DNA (Citosina-5-)-Metiltransferases , Metilação de DNA , Pré-Eclâmpsia , Trofoblastos , Trofoblastos/metabolismo , Feminino , Pré-Eclâmpsia/genética , Pré-Eclâmpsia/metabolismo , Pré-Eclâmpsia/patologia , Gravidez , Humanos , DNA (Citosina-5-)-Metiltransferases/genética , DNA (Citosina-5-)-Metiltransferases/metabolismo , Fusão Celular , Placenta/metabolismo , DNA (Citosina-5-)-Metiltransferase 1/metabolismo , DNA (Citosina-5-)-Metiltransferase 1/genética
2.
Biochim Biophys Acta Mol Cell Res ; 1871(7): 119768, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38838858

RESUMO

The regulatory mechanism of the transcription factor GATA3 in the differentiation and maturation process of extravillous trophoblasts (EVT) in early pregnancy placenta, as well as its relevance to the occurrence of pregnancy disorders, remains poorly understood. This study leveraged single-cell RNA sequencing data from placental organoid models and placental tissue to explore the dynamic changes in GATA3 expression during EVT maturation. The expression pattern exhibited an initial upregulation followed by subsequent downregulation, with aberrant GATA3 localization observed in cases of recurrent miscarriage (RM). By identifying global targets regulated by GATA3 in primary placental EVT cells, JEG3, and HTR8/SVneo cell lines, this study offered insights into its regulatory mechanisms across different EVT cell models. Shared regulatory targets among these cell types and activation of trophoblast cell marker genes emphasized the importance of GATA3 in EVT differentiation and maturation. Knockdown of GATA3 in JEG3 cells led to repression of GATA3-induced epithelial-mesenchymal transition (EMT), as evidenced by changes in marker gene expression levels and enhanced migration ability. Additionally, interference with GATA3 accelerated cellular senescence, as indicated by reduced proliferation rates and increased activity levels for senescence-associated ß-galactosidase enzyme, along with elevated expression levels for senescence-associated genes. This study provides comprehensive insights into the dual role of GATA3 in regulating EMT and cellular senescence during EVT differentiation, shedding light on the dynamic changes in GATA3 expression in normal and pathological placental conditions.

3.
Hum Reprod ; 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38725195

RESUMO

STUDY QUESTION: Can exposure to palmitic acid (PA), a common saturated fatty acid, modulate autophagy in both human and mouse trophoblast cells through the regulation of acyl-coenzyme A-binding protein (ACBP)? SUMMARY ANSWER: PA exposure before and during pregnancy impairs placental development through mechanisms involving placental autophagy and ACBP expression. WHAT IS KNOWN ALREADY: High-fat diets, including PA, have been implicated in adverse effects on human placental and fetal development. Despite this recognition, the precise molecular mechanisms underlying these effects are not fully understood. STUDY DESIGN, SIZE, DURATION: Extravillous trophoblast (EVT) cell line HTR-8/SVneo and human trophoblast stem cell (hTSC)-derived EVT (hTSCs-EVT) were exposed to PA or vehicle control for 24 h. Female wild-type C57BL/6 mice were divided into PA and control groups (n = 10 per group) and subjected to a 12-week dietary intervention. Afterward, they were mated with male wild-type C57BL/6 mice and euthanized on Day 14 of gestation. Female ACBPflox/flox mice were also randomly assigned to control and PA-exposed groups (each with 10 mice), undergoing the same dietary intervention and mating with ACBPflox/floxELF5-Cre male mice, followed by euthanasia on Day 14 of gestation. The study assessed the effects of PA on mouse embryonic development and placental autophagy. Additionally, the role of ACBP in the pathogenesis of PA-induced placental toxicity was investigated. PARTICIPANTS/MATERIALS, SETTING, METHODS: The findings were validated using real-time PCR, Western blot, immunofluorescence, transmission electron microscopy, and shRNA knockdown approaches. MAIN RESULTS AND THE ROLE OF CHANCE: Exposure to PA-upregulated ACBP expression in both human HTR-8/SVneo cells and hTSCs-EVT, as well as in mouse placenta. PA exposure also induced autophagic dysfunction in HTR-8/SVneo cells, hTSCs-EVT, and mouse placenta. Through studies on ACBP placental conditional knockout mice and ACBP knockdown human trophoblast cells, it was revealed that reduced ACBP expression led to trophoblast malfunction and affected the expression of autophagy-related proteins LC3B-II and P62, thereby impacting embryonic development. Conversely, ACBP knockdown partially mitigated PA-induced impairment of placental trophoblast autophagy, observed both in vitro in human trophoblast cells and in vivo in mice. LARGE SCALE DATA: N/A. LIMITATIONS, REASONS FOR CAUTION: Primary EVT cells from early pregnancy are fragile, limiting research use. Maintaining their viability is tough, affecting data reliability. The study lacks depth to explore PA diet cessation effects after 12 weeks. Without follow-up, understanding postdiet impacts on pregnancy stages is incomplete. Placental abnormalities linked to elevated PA diet in embryos lack confirmation due to absence of control groups. Clarifying if issues stem solely from PA exposure is difficult without proper controls. WIDER IMPLICATIONS OF THE FINDINGS: Consuming a high-fat diet before and during pregnancy may result in complications or challenges in successfully carrying the pregnancy to term. It suggests that such dietary habits can have detrimental effects on the health of both the mother and the developing fetus. STUDY FUNDING/COMPETING INTEREST(S): This work was supported in part by the National Natural Science Foundation of China (82171664, 82301909) and the Natural Science Foundation of Chongqing Municipality of China (CSTB2022NS·CQ-LZX0062, cstc2019jcyj-msxmX0749, and cstc2021jcyj-msxmX0236). The authors declare that they have no conflict of interest. TRIAL REGISTRATION NUMBER: N/A.

4.
J Chem Phys ; 160(20)2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38804489

RESUMO

The thermophysical properties and elemental abundances of the noble gases in terrestrial materials can provide unique insights into the Earth's evolution and mantle dynamics. Here, we perform extensive ab initio molecular dynamics simulations to determine the melting temperature and sound velocity of neon up to 370 GPa and 7500 K to constrain its physical state and storage capacity, together with to reveal its implications for the deep interior of the Earth. It is found that solid neon can exist stably under the lower mantle and inner core conditions, and the abnormal melting of neon is not observed under the entire temperature (T) and pressure (P) region inside the Earth owing to its peculiar electronic structure, which is substantially distinct from other heavier noble gases. An inspection of the reduction for sound velocity along the Earth's geotherm evidences that neon can be used as a light element to account for the low-velocity anomaly and density deficit in the deep Earth. A comparison of the pair distribution functions and mean square displacements of MgSiO3-Ne and Fe-Ne alloys further reveals that MgSiO3 has a larger neon storage capacity than the liquid iron under the deep Earth condition, indicating that the lower mantle may be a natural deep noble gas storage reservoir. Our results provide valuable information for studying the fundamental behavior and phase transition of neon in a higher T-P regime, and further enhance our understanding for the interior structure and evolution processes inside the Earth.

5.
World J Gastrointest Oncol ; 16(4): 1309-1318, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38660663

RESUMO

BACKGROUND: Despite continuous changes in treatment methods, the survival rate for advanced hepatocellular carcinoma (HCC) patients remains low, highlighting the importance of diagnostic methods for HCC. AIM: To explore the efficacy of texture analysis based on multi-parametric magnetic resonance (MR) imaging (MRI) in predicting microvascular invasion (MVI) in preoperative HCC. METHODS: This study included 105 patients with pathologically confirmed HCC, categorized into MVI-positive and MVI-negative groups. We employed Original Data Analysis, Principal Component Analysis, Linear Discriminant Analysis (LDA), and Non-LDA (NDA) for texture analysis using multi-parametric MR images to predict preoperative MVI. The effectiveness of texture analysis was determined using the B11 program of the MaZda4.6 software, with results expressed as the misjudgment rate (MCR). RESULTS: Texture analysis using multi-parametric MRI, particularly the MI + PA + F dimensionality reduction method combined with NDA discrimination, demonstrated the most effective prediction of MVI in HCC. Prediction accuracy in the pulse and equilibrium phases was 83.81%. MCRs for the combination of T2-weighted imaging (T2WI), arterial phase, portal venous phase, and equilibrium phase were 22.86%, 16.19%, 20.95%, and 20.95%, respectively. The area under the curve for predicting MVI positivity was 0.844, with a sensitivity of 77.19% and specificity of 91.67%. CONCLUSION: Texture analysis of arterial phase images demonstrated superior predictive efficacy for MVI in HCC compared to T2WI, portal venous, and equilibrium phases. This study provides an objective, non-invasive method for preoperative prediction of MVI, offering a theoretical foundation for the selection of clinical therapy.

6.
Biol Reprod ; 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38647664

RESUMO

OBJECTIVE: The purpose of this study is to investigate the role of high mobility group protein B1 (HMGB1) in placental development and fetal growth. METHODS: We employed the Cre-loxP recombination system to establish a placenta-specific HMGB1 knockout mouse model. Breeding HMGB1flox/flox mice with Elf5-Cre mice facilitated the knockout, leveraging Elf5 expression in extra-embryonic ectoderm, ectoplacental cone, and trophoblast giant cells at 12.5 days of embryonic development. The primary goal of this model was to elucidate the molecular mechanism of HMGB1 in placental development, assessing parameters such as placental weight, fetal weight, and bone development. Additionally, we utilized lentiviral interference and overexpression of HMGB1 in human trophoblast cells to further investigate HMGB1's functional role. RESULTS: Our findings indicate that HMGB1flox/floxElf5cre/+ mouse display fetal growth restriction (FGR), characterized by decreased placental and fetal weight and impaired bone development. And the absence of HMGB1 inhibits autophagosome formation, impairs lysosomal degradation, and disrupts autophagic flux. Depletion of HMGB1 in human trophoblast cells also suppresses cell viability, proliferation, migration, and invasion by inhibiting the ERK signaling pathway. Overexpression of HMGB1 observed the opposite phenotypes. CONCLUSIONS: HMGB1 participates in the regulation of autophagy through the ERK signaling pathway and affects placental development.

7.
Brain Res Bull ; 211: 110937, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38570077

RESUMO

Adult survivors of childhood brain tumors often present with cognitive deficits that affect their quality of life. Studying brain structure and function in brain tumor survivors can help understand the underlying mechanisms of their cognitive deficits to improve long-term prognosis of these patients. This study analyzed voxel-based morphometry (VBM) derived from T1-weighted MRI and the amplitude of low-frequency fluctuation (ALFF) from resting-state functional magnetic resonance imaging (rs-fMRI) to examine the structural and functional alterations in 35 brain tumor survivors using 35 matching healthy individuals as controls. Compared with healthy controls, brain tumor survivors had decreased gray matter volumes (GMV) in the thalamus and increased GMV in the superior frontal gyrus. Functionally, brain tumor survivors had lower ALFF values in the inferior temporal gyrus and medial prefrontal area and higher ALFF values in the thalamus. Importantly, we found concurrent but negatively correlated structural and functional alterations in the thalamus based on observed significant differences in GMV and ALFF values. These findings on concurrent brain structural and functional alterations provide new insights towards a better understanding of the cognitive deficits in brain tumor survivors.


Assuntos
Neoplasias Encefálicas , Sobreviventes de Câncer , Imageamento por Ressonância Magnética , Tálamo , Humanos , Masculino , Feminino , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/patologia , Imageamento por Ressonância Magnética/métodos , Tálamo/diagnóstico por imagem , Tálamo/patologia , Adulto , Adulto Jovem , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Adolescente , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Encéfalo/fisiopatologia , Imagem Multimodal/métodos , Criança , Sobreviventes
8.
Sci Data ; 11(1): 13, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38167545

RESUMO

Early and accurate diagnosis of ear deformities in newborns is crucial for an effective non-surgical correction treatment, since this commonly seen ear anomalies would affect aesthetics and cause mental problems if untreated. It is not easy even for experienced physicians to diagnose the auricular deformities of newborns and the classification of the sub-types, because of the rich bio-metric features embedded in the ear shape. Machine learning has already been introduced to analyze the auricular shape. However, there is little publicly available datasets of ear images from newborns. We released a dataset that contains quality-controlled photos of 3,852 ears from 1,926 newborns. The dataset also contains medical diagnosis of the ear shape, and the health data of each newborn and its mother. Our aim is to provide a freely accessible dataset, which would facilitate researches related with ear anatomies, such as the AI-aided detection and classification of auricular deformities and medical risk analysis.


Assuntos
Orelha Externa , Aprendizado de Máquina , Humanos , Recém-Nascido , Orelha Externa/anormalidades , Orelha Externa/cirurgia , Médicos , Medição de Risco
9.
Laryngoscope ; 134(1): 148-153, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37243347

RESUMO

Hearing improvement is another basic requirement for microtia patients in addition to aesthetic needs. This quantitative framework fabrication method can reduce the learning curve, obtain satisfactory aesthetic results with few complications, and reserve a certain space for future canalplasty. Laryngoscope, 134:148-153, 2024.


Assuntos
Microtia Congênita , Cartilagem Costal , Procedimentos de Cirurgia Plástica , Humanos , Cartilagem Costal/transplante , Orelha Externa/cirurgia , Microtia Congênita/cirurgia , Cartilagem/transplante
10.
Altern Ther Health Med ; 30(2): 131-135, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37856809

RESUMO

Objective: This study investigated the expression and clinical significance of Melanoma Associated Antigen (MAGE)-A proteins and mRNA in patients with non-small cell lung cancer (NSCLC). Methods: A retrospective study was conducted, and we selected a cohort of 88 NSCLC patients treated at our hospital from January 2015 to January 2020. Adjacent tissues were chosen as controls. The expression of MAGE-A proteins in lung cancer and adjacent tissues was assessed via Western blot, while MAGE-As mRNA expression was measured using RT-PCR. Results: The relative expression levels of MAGE-A proteins and mRNA in NSCLC tissues were significantly higher than those in adjacent tissues (P < .05), with values of (0.343 ± 0.101) and (0.728 ± 0.112), respectively. Furthermore, MAGE-As protein expression was significantly higher in stage III - IV lung cancer compared to stage I - II (P < .05). No significant differences were observed in MAGE-A protein expression concerning gender, age, tumor diameter, pathological type, and differentiation degree (P > .05). The relative expression of MAGE-As mRNA was significantly higher in clinical stage III - IV and moderately differentiated lung cancer tissues compared to stage I - II and well-differentiated tissues (P < .05). No significant differences were found in MAGE-As mRNA expression concerning gender, age, tumor diameter, and pathological type (P > .05). Patients with high MAGE-As mRNA expression had a significantly shorter median overall survival of 33 months (95% CI: 31.64-34.36) compared to those with low MAGE-As mRNA expression (P < .05). However, no significant difference was observed in median overall survival between patients with high and low MAGE-As protein expression (P > .05). Conclusions: In NSCLC, the up-regulation of MAGE-A proteins and mRNA is associated with clinical stage and differentiation degree, warranting further investigation.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Estudos Retrospectivos , RNA Mensageiro , Relevância Clínica , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/metabolismo
11.
Sci Rep ; 13(1): 21558, 2023 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-38057437

RESUMO

To explore the influence of wind speed on the quality of tobacco in this study, we employed a heat pump-powered intensive curing barn and a three-stage curing process. By evaluating the influence of fan parameters on the quality of tobacco leaves at different curing stages, the optimal wind speed was determined. After adopting the optimized wind speed process, the degradation of macromolecular substances was faster, the accumulation of aroma substances was delayed to 55 °C, and the accumulation was more complete. Among them, the contents of reducing sugar and total sugar in flue-cured tobacco leaves were 22.25% and 29.2%, respectively, which were lower than those in the control group. The sugar was converted into more aroma substances, and the total amount of neutral aroma substances was 48.82% higher than that of the control group. The content of related aroma substances increased significantly. The content of petroleum ether extract related to aroma substances increased by 0.93% compared with the control group. The macromolecular substances were degraded more fully than the control group, such as the starch content decreased to 1.56%. The results of metabolomics showed that the contents of aldehydes, heterocyclic compounds, alcohols, ketones and esters increased significantly in different degrees after this process. These results show that the optimization of wind speed parameters can significantly improve the baking quality of tobacco leaves. This study provides a reference for the optimization of the flue-cured tobacco baking process.


Assuntos
Temperatura Alta , Vento , Nicotiana , Folhas de Planta , Açúcares , Substâncias Macromoleculares
12.
Materials (Basel) ; 16(21)2023 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-37959641

RESUMO

Acoustic metasurfaces, as two-dimensional acoustic metamaterials, are a current research topic for their sub-wavelength thickness and excellent acoustic wave manipulation. They hold significant promise in noise reduction and isolation, cloaking, camouflage, acoustic imaging, and focusing. Resonant structural units are utilized to construct acoustic metasurfaces with the unique advantage of controlling large wavelengths within a small size. In this paper, the recent research progresses of the resonant metasurfaces are reviewed, covering the design mechanisms and advances of structural units, the classification and application of the resonant metasurfaces, and the tunable metasurfaces. Finally, research interest in this field is predicted in future.

13.
Phys Chem Chem Phys ; 25(43): 29633-29640, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37880996

RESUMO

We conducted first-principles calculations to investigate the dynamic braiding of local edge states and the spin topological transport mechanism in a strong topological MoS1.75Te0.25 matrix. The presence of type-II Van Hove singularity in the middle of the X-S path indicates a strong cohesive interaction and a paring condensation mechanism within the matrix. The surface state data of MoS1.75Te0.25 clearly demonstrate the characteristic features of strong regular loop braiding in spin transport. The spin Hall conductivity of the matrix was determined from the anisotropic characteristics of the spin Berry curvature. The phase transition of the spin Hall conductivity was evidenced by the positive sign of local spin polarization strength, primarily contributed by the dz2 orbital of Mo atoms, and the negative sign of spin polarization strength, mainly contributed by the p-px orbitals of S atoms. Moreover, the inclusion of Te selectively tuned the spin transport efficiency of the dz2 and px orbitals. Comprehensive braiding and readout of edge states can be achieved using an artificially designed MoS1.75Te0.25 spintronic device. This 2D fractional braiding holds significant potential for applications in topological quantum computation.

14.
Environ Sci Technol ; 57(42): 16053-16064, 2023 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-37824517

RESUMO

Rhizosphere microbiota are an important factor impacting plant uptake of pollutants. However, little is known about how microbial nitrogen (N) transformation in the rhizosphere affects the uptake and accumulation of antibiotics in plants. Here, we determined recruitment of N transformation functional bacteria upon ciprofloxacin (CIP) exposure, by comparing differences in assembly processes of both rhizospheric bacterial communities and N transformation between two choysum (Brassica parachinensis) varieties differing in CIP accumulation. The low accumulation variety (LAV) of CIP recruited more host bacteria (e.g., Nitrospiria and Nitrolancea) carrying nitrification genes (mainly nxrA) but fewer host bacteria carrying denitrification genes, especially narG, relative to the high accumulation variety (HAV) of CIP. The nxrA and narG abundance in the LAV rhizosphere were, respectively, 1.6-7.8 fold higher and 1.4-3.4 fold lower than those in the HAV rhizosphere. Considering that nitrate can decrease CIP uptake into choysum through competing for the proton motive force and energy, such specific bacteria recruitment in LAV favored the production and utilization of nitrate in its rhizosphere, thus limiting its CIP accumulation with 1.6-2.4 fold lower than the HAV. The findings give insight into the mechanism underlying low pollutant accumulation, filling the knowledge gap regarding the profound effects of rhizosphere microflora and N transformation processes on antibiotic accumulation in crops.


Assuntos
Brassica , Ciprofloxacina , Rizosfera , Nitratos , Nitrogênio/análise , Antibacterianos , Bactérias/genética , Plantas , Solo , Microbiologia do Solo
15.
J Clin Med ; 12(18)2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37762842

RESUMO

Bone conduction devices (BCDs) are widely used in the treatment of conductive hearing loss (CHL), but their applications on unilateral CHL (UCHL) patients remain controversial. To evaluate the effects of BCDs in UCHL, a systematic search was undertaken until May 2023 following the PRISMA guidelines. Among the 391 references, 21 studies met the inclusion criteria and were ultimately selected for review. Data on hearing thresholds, speech recognition, sound localization, and subjective questionnaire outcomes were collected and summarized. Moderate hearing threshold improvements were found in UCHL patients aided with BCDs. Their speech recognition abilities improved significantly. However, sound localization results showed wide individual variations. According to subjective questionnaires, BCDs had an overall positive influence on the daily life of UCHL patients, although several unfavorable experiences were reported by some of them. We concluded that the positive audiological benefits and subjective questionnaire results have made BCDs a credible intervention for UCHL patients. Before final implantations, UCHL patients should first go through a period of time when they were fitted with non-implantable BCDs as a trial.

16.
Phys Chem Chem Phys ; 25(27): 18224-18232, 2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37395132

RESUMO

The electrocatalytic nitrogen reduction reaction (NRR) is a promising technology for the synthesis of NH3 in an ambient environment. However, developing low-cost and high-efficiency electrocatalysts still remains a long-standing challenge. In this work, density function theory (DFT) calculations are done to systematically investigate the NRR catalytic activity of transition metals (TM = Sc-Cu, Y-Ag, and Hf-Au) supported on monolayer graphyne (GY). TM@GY (TM = Sc, V, Mn, Y, Tc, and Os) with excellent NRR performance are demonstrated. The mixed pathway is the most favorable for Sc, V, Y, and Os@GY with the potentials of -0.37, -0.27, -0.40, and -0.36 V, respectively, while the distal reaction pathway is most favorable for Mn and Tc@GY with the potentials of -0.37 and -0.42 V. Most strikingly, Mn, Tc, and Os@GY exhibit high NRR selectivity. This work provides a screening scheme for exploring highly efficient electrocatalysts for the electrochemical NRR under ambient conditions.

17.
Environ Int ; 178: 108054, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37354883

RESUMO

Microbial degradation has been confirmed as effective and environmentally friendly approach to remediate phthalates from the environment, and hydrolase is an effective element for contaminant degradation. In the present study, a novel dibutyl phthalate (DBP)-hydrolyzing carboxylesterase (named PS06828) from Pseudomonas sp. PS1 was heterogeneously expressed in E. coli, which was identified as a new member of the lipolytic family VI. Purified PS06828 could efficiently degrade DBP with a wide range of temperature (25-37 °C) and pH (6.5-9.0). Multi-spectroscopy methods combined with molecular docking were employed to study the interaction of PS06828 with DBP. Fluorescence and UV-visible absorption spectra revealed the simultaneous presence of static and dynamic component in the fluorescence quenching of PS06828 by DBP. Synchronous fluorescence and circular dichroism spectra showed inconspicuous alteration in micro-environmental polarity around amino acid residues but obvious increasing of α-helix and reducing of ß-sheet and random coil in protein conformation. Based on the information on exact binding sites of DBP on PS06828 provided by molecular docking, the catalytic mechanism mediated by key residues (Ser113, Asp166, and His197) was proposed and subsequently confirmed by site-directed mutagenesis. The results can strengthen our mechanistic understanding of family VI esterase involved in hydrolysis of phthalic acid esters, and provide a solid foundation for further enzymatic modification.


Assuntos
Esterases , Ácidos Ftálicos , Esterases/genética , Esterases/metabolismo , Dibutilftalato , Simulação de Acoplamento Molecular , Escherichia coli/genética , Escherichia coli/metabolismo , Ácidos Ftálicos/metabolismo
18.
BMJ Open ; 13(4): e069345, 2023 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-37116992

RESUMO

OBJECTIVE: Recent studies have shown that blood urea nitrogen to creatinine (BUN/Cr) ratio might be an effective marker for the prognosis of patients with respiratory diseases. Herein, we aimed to assess the association between BUN/Cr ratio and the risk of in-hospital mortality in patients with trauma-related acute respiratory distress syndrome (ARDS). DESIGN: A retrospective cohort study. SETTING AND PARTICIPANTS: 1034 patients were extracted from the Medical Information Mart for Intensive Care-III (MIMIC-III) database. PRIMARY AND SECONDARY OUTCOME MEASURES: The primary outcome of the study was in-hospital mortality, defined by the vital status at the time of hospital discharge (ie, survivors and non-survivors). RESULTS: Of the total patients, 191 (18.5%) died in hospital. The median follow-up duration was 16.0 (8.3-26.6) days. The results showed that high level of BUN/Cr ratio was significantly associated with an increased risk of in-hospital mortality (15.54-21.43: HR=2.00, 95% CI: (1.18 to 3.38); >21.43: HR=1.76, 95% CI: (1.04 to 2.99)) of patients with trauma-related ARDS. In patients with trauma-related ARDS that aged ≥65 years old, male and female, Onychomycosis Severity Index (OSI)>98, Revised Trauma Score (RTS)>11, Simplified Acute Physiology Score II (SAPS-II)>37 and sequential organ failure assessment (SOFA) scores≤7, BUN/Cr ratio was also related to the increased risk of in-hospital mortality (all p<0.05). The predictive performance of BUN/Cr ratio for in-hospital mortality was superior to BUN or Cr, respectively, with the area under the curve of receiver operator characteristic curve at 0.6, and that association was observed in age, gender, OSI, RTS, SAPS-II and SOFA score subgroups. CONCLUSION: BUN/Cr ratio may be a potential biomarker for the risk of in-hospital mortality of trauma-related ARDS, which may help the clinicians to identify high-risk individuals and to implement clinical interventions.


Assuntos
Síndrome do Desconforto Respiratório , Humanos , Masculino , Feminino , Idoso , Nitrogênio da Ureia Sanguínea , Estudos Retrospectivos , Creatinina , Mortalidade Hospitalar , Prognóstico , Síndrome do Desconforto Respiratório/etiologia , Curva ROC
19.
Nanomaterials (Basel) ; 13(6)2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36985938

RESUMO

Lightweight, high-temperature-resistant carbon-bonded carbon fiber (CBCF) composites with excellent thermal insulation properties are desirable materials for thermal protection systems in military and aerospace applications. Here, glucose was introduced into the polyacrylamide hydrogel to form the glucose-polyacrylamide (Glu-PAM) hydrogel. The CBCF composites were prepared using the Glu-PAM hydrogel as a brand-new binder, and the synergistic effect between glucose and acrylamide was investigated. The results showed the Glu-PAM hydrogel could limit the foaming of glucose and enhance the carbon yield of glucose. Meanwhile, the dopamine-modified chopped carbon fiber could be uniformly mixed by high-speed shearing to form a slurry with the Glu-PAM hydrogel. Finally, the slurry was successfully extruded and molded to prepare CBCF composites with a density of 0.158~0.390 g cm-3 and excellent thermal insulation performance and good mechanical properties. The compressive strength of CBCF composites with a density of 0.158 g cm-3 in the Z direction is 0.18 MPa, and the thermal conductivity in the Z direction at 25 °C and 1200 °C is 0.10 W m-1 k-1 and 0.20 W m-1 k-1, respectively. This study provided an efficient, environment-friendly, and cost-effective strategy for the preparation of CBCF composites.

20.
Opt Express ; 31(2): 3258-3268, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36785322

RESUMO

A Bragg grating is successfully inscribed in a piece of strongly coupled seven-core fiber (SCF). There are two separate Bragg resonance notches observed in the transmission spectrum, corresponding to backward coupling of HE11-like and HE12-like supermodes of the SCF. The mode coupling mechanism of the Bragg grating is theoretically investigated via modeling and analyzing modal properties of the SCF. The theoretical results agree well with the experimental results. Since the SCF is spliced between two standard single mode fibers with central alignments at both ends, the transmission spectrum of the device also contains a set of interference fringe due to modal interference between the supermodes. The device's responses to temperature and curvature are experimentally measured, respectively. The obtained temperature sensitivities and curvature sensitivities of the supermode Bragg grating notches are 9.55 pm/°C and 9.55 pm/°C, -1.8 pm/m-1 and -112.3 pm/m-1, respectively. The obtained temperature sensitivity and curvature sensitivity of one of the interference spectrum dips are 11.8 pm/°C and -3909.8 pm/m-1, respectively. This device is potentially useful for simultaneous measurement of temperature and curvature.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA