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1.
Biosens Bioelectron ; 257: 116330, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38677022

RESUMO

Perfluorooctanoic acid (PFOA) poses a threat to the environment and human health due to its persistence, bioaccumulation, and reproductive toxicity. Herein, a lanthanide metal-organic framework (Ln-MOF)-based surface molecularly imprinted polymers (SMIPs) ratiometric fluorescence probe (Eu/Tb-MOF@MIPs) and a smartphone-assisted portable device were developed for the detection of PFOA with high selectivity in real water samples. The integration of Eu/Tb MOFs as carriers not only had highly stable multiple emission signals but also prevented deformation of the imprinting cavity of MIPs. Meanwhile, the MIPs layer preserved the fluorescence of Ln-MOF and provided selective cavities for improved specificity. Molecular dynamics (MD) was employed to simulate the polymerization process of MIPs, revealing that the formation of multiple recognition sites was attributed to the establishment of hydrogen bonds between functional monomers and templates. The probe showed a good linear relationship with PFOA concentration in the range of 0.02-2.8 µM, by giving the limit of detection (LOD) of 0.98 nM. Additionally, The red-green-blue (RGB) values analysis based on the smartphone-assisted portable device demonstrated a linear relationship of 0.1-2.8 µM PFOA with the LOD of 3.26 nM. The developed probe and portable device sensing platform exhibit substantial potential for on-site detecting PFOA in practical applications and provide a reliable strategy for the intelligent identification of important targets in water environmental samples.


Assuntos
Técnicas Biossensoriais , Caprilatos , Corantes Fluorescentes , Fluorocarbonos , Estruturas Metalorgânicas , Polímeros Molecularmente Impressos , Smartphone , Poluentes Químicos da Água , Estruturas Metalorgânicas/química , Caprilatos/análise , Caprilatos/química , Corantes Fluorescentes/química , Técnicas Biossensoriais/instrumentação , Fluorocarbonos/química , Fluorocarbonos/análise , Polímeros Molecularmente Impressos/química , Poluentes Químicos da Água/análise , Limite de Detecção , Elementos da Série dos Lantanídeos/química , Espectrometria de Fluorescência/métodos , Humanos
2.
Curr Biol ; 34(9): 1866-1879.e6, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38608677

RESUMO

Prefrontal (PFC) and hippocampal (HPC) sequences of neuronal firing modulated by theta rhythms could represent upcoming choices during spatial memory-guided decision-making. How the PFC-HPC network dynamically coordinates theta sequences to predict specific goal locations and how it is interrupted in memory impairments induced by amyloid beta (Aß) remain unclear. Here, we detected theta sequences of firing activities of PFC neurons and HPC place cells during goal-directed spatial memory tasks. We found that PFC ensembles exhibited predictive representation of the specific goal location since the starting phase of memory retrieval, earlier than the hippocampus. High predictive accuracy of PFC theta sequences existed during successful memory retrieval and positively correlated with memory performance. Coordinated PFC-HPC sequences showed PFC-dominant prediction of goal locations during successful memory retrieval. Furthermore, we found that theta sequences of both regions still existed under Aß accumulation, whereas their predictive representation of goal locations was weakened with disrupted spatial representation of HPC place cells and PFC neurons. These findings highlight the essential role of coordinated PFC-HPC sequences in successful memory retrieval of a precise goal location.


Assuntos
Objetivos , Hipocampo , Córtex Pré-Frontal , Memória Espacial , Ritmo Teta , Córtex Pré-Frontal/fisiologia , Ritmo Teta/fisiologia , Animais , Hipocampo/fisiologia , Masculino , Memória Espacial/fisiologia , Neurônios/fisiologia , Camundongos
3.
Curr Med Imaging ; 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38532603

RESUMO

BACKGROUND: In the realm of cancer studies,the differences among the biological behavior of oligometastatic prostate cancer (OPCa), localized prostate cancer (LPCa), and widely prostate cancer (WPCa) are still unclear. OBJECTIVES: The purpose of our study was to assess the clinical and intravoxel incoherent motion (IVIM) parameters of tumor burden in OPCa. In addition, the correlation between clinical and IVIM parameters and the prostate-specific antigen nadir (PSAN) and time to nadir (TTN) during initial androgen deprivation therapy (ADT) in OPCa was explored. It was found that the IVIM parameters could effectively differentiate LPCa and WPCa, as well as LPCa and OPC. Moreover, Gleason score (GS) was positively correlated with PSAN, while prostate volume was positively correlated with TTN. METHODS: About 54 patients were included in this retrospective study (mean age=74±7.4 years). ADC, D, D*, and f were acquired according to the biexponential Diffusion Weighted Imaging (DWI) model. The Kruskal-Wallis test was used to test the differences in clinical and IVIM parameters among the three groups. The Receiver Operating Characteristic (ROC) curve was used to evaluate the discrimination abilities. The Area Under the Curve (AUC) was compared using the DeLong test. Furthermore, Spearman correlation analysis was performed to assess the correlation between clinical and IVIM parameters of PSAN and TTN during initial ADT with OPCa. RESULTS: There were significant differences among the three groups observed for age, PSA, GS, ADC, D and D* values (P<0.05). Multi-parameter pairwise comparison results showed that significant differences between LPCa and WPCa were observed for the age, PSA, GS, ADC, D and D* values (P<0.05). However, D* was different between the LPCa and OPCa groups (P=0.032). GS showed a significant positive correlation with PSAN (Rho=0.594, P=0.042), and prostate volume showed a significant positive correlation with TTN (Rho=0.777, P=0.003). CONCLUSIONS: The IVIM parameters can effectively differentiate LPCa and WPCa, as well as LPCa and OPCa. Moreover, there was a certain trend in their distribution, which could reflect the tumor burden of PCa.

4.
Sci Total Environ ; 922: 171115, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38401730

RESUMO

In the current context of water environmental monitoring and pollution control, there's a crucial need for rapid and simple methods to detect multi-pollutant. We herein report an easy one-step hydrothermal synthesis method to produce Eu-based metal-organic frameworks (Eu MOFs), which was used as a fluorescent probe to detect the aquatic environmental pollutants of ciprofloxacin (CIP) and aluminum ions (Al3+). This fluorescent sensor enabled the cascade detection of CIP and Al3+ through fluorescence enhancement and ratio fluorescence response, respectively. The introduction of CIP significantly turned on the characteristic fluorescence of Eu MOFs at 595 nm and 616 nm through the "antenna effect". Based on this, the sensor enables quantitative detection of CIP within a linear range of 0-120 µM with a LOD as low as 50.421 nM. In the presence of Al3+, the fluorescence emission of Eu MOFs-CIP was sharply turned off due to strong Al3+ coordination with CIP, while the blue fluorescence emission of CIP was remarkably enhanced. And thus allowing ratio fluorescence quantitative detection of Al3+ (LOD = 2.681 µM). The introduction of CIP and Al3+ in cascade resulted in distinct fluorescence color changes from colorless to red and eventually to blue, exhibiting pronounced fluorescence characteristics. This observable phenomenon enables the visual detection of CIP and Al3+ in both aqueous phase and paper test strips. By combining the analysis of fluorescence chromaticity with the use of a smartphone, the fluorescence color of test papers allows for simple quantitative determination, which provides a convenient and accessible approach for quantifying CIP and Al3+ in water environments.


Assuntos
Poluentes Ambientais , Elementos da Série dos Lantanídeos , Ciprofloxacina , Espectrometria de Fluorescência , Água , Corantes Fluorescentes
5.
Bioinformatics ; 40(2)2024 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-38317025

RESUMO

MOTIVATION: Dropout events bring challenges in analyzing single-cell RNA sequencing data as they introduce noise and distort the true distributions of gene expression profiles. Recent studies focus on estimating dropout probability and imputing dropout events by leveraging information from similar cells or genes. However, the number of dropout events differs in different cells, due to the complex factors, such as different sequencing protocols, cell types, and batch effects. The dropout event differences are not fully considered in assessing the similarities between cells and genes, which compromises the reliability of downstream analysis. RESULTS: This work proposes a hybrid Generative Adversarial Network with dropouts identification to impute single-cell RNA sequencing data, named AGImpute. First, the numbers of dropout events in different cells in scRNA-seq data are differentially estimated by using a dynamic threshold estimation strategy. Next, the identified dropout events are imputed by a hybrid deep learning model, combining Autoencoder with a Generative Adversarial Network. To validate the efficiency of the AGImpute, it is compared with seven state-of-the-art dropout imputation methods on two simulated datasets and seven real single-cell RNA sequencing datasets. The results show that AGImpute imputes the least number of dropout events than other methods. Moreover, AGImpute enhances the performance of downstream analysis, including clustering performance, identifying cell-specific marker genes, and inferring trajectory in the time-course dataset. AVAILABILITY AND IMPLEMENTATION: The source code can be obtained from https://github.com/xszhu-lab/AGImpute.


Assuntos
Análise de Célula Única , Análise da Expressão Gênica de Célula Única , Análise de Sequência de RNA/métodos , Reprodutibilidade dos Testes , Análise de Célula Única/métodos , Transcriptoma , Software , Análise por Conglomerados , Perfilação da Expressão Gênica
6.
Adv Mater ; 36(18): e2312140, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38241656

RESUMO

Noble metals have been widely used in catalysis, however, the scarcity and high cost of noble metal motivate researchers to balance the atomic efficiency and atomic density, which is formidably challenging. This article proposes a robust strategy for fabricating 3D amorphous noble metal-based oxides with simultaneous enhancement on atomic efficiency and density with the assistance of atomic channels, where the atomic utilization increases from 18.2% to 59.4%. The unique properties of amorphous bimetallic oxides and formation of atomic channels have been evidenced by detailed experimental characterizations and theoretical simulations. Moreover, the universality of the current strategy is validated by other binary oxides. When Cu2IrOx with atomic channels (Cu2IrOx-AE) is used as catalyst for oxygen evolution reaction (OER), the mass activity and turnover frequency value of Cu2IrOx-AE are 1-2 orders of magnitude higher than CuO/IrO2 and Cu2IrOx without atomic channels, largely outperforming the reported OER catalysts. Theoretical calculations reveal that the formation of atomic channels leads to various Ir sites, on which the proton of adsorbed *OH can transfer to adjacent O atoms of [IrO6]. This work may attract immediate interest of researchers in material science, chemistry, catalysis, and beyond.

7.
Spectrochim Acta A Mol Biomol Spectrosc ; 308: 123687, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38042123

RESUMO

Essential to many activities in our bodies, ascorbic acid is a small molecule essential to human health and physiological processes. In this study, a covalent organic framework called TpNda-COF was synthesized, which is composed of Tp (triformylephloroglucinol) and Nda (1, 5-napthalenediamine). This framework acts as a mimic enzyme and displays excellent oxidase-like activity when stimulated with purple light (at = 405 nm). It catalyzes the oxidation of 3,3',5,5'-tetramethylbenzydine (TMB) by generating O2- free radicals in the presence of oxygen. The resulting oxTMB shows a characteristic absorption peak at 652 nm. The biomimetic catalysis efficiency is significantly improved due to spatial restriction. By introducing ascorbic acid (AA) in the system, the blue oxTMB is reduced to colorless TMB. The decrease in absorption peak intensity can be quantitatively measured using a UV-Vis spectrophotometer, enabling the detection of AA. The sensing platform demonstrates excellent selectivity and sensitivity. It has a wide linear detection range from 5 µM to 50 µM, with a low detection limit of 1.44 µM. Advantages such as the easy control of light, high stability and efficient oxidation are provided by the TpNda-COF mimic oxidase. This innovative method presents a promising and cost-effective approach for rapid detection of ascorbic acid, with potential applications across various fields.


Assuntos
Estruturas Metalorgânicas , Humanos , Ácido Ascórbico , Colorimetria/métodos , Oxirredutases/metabolismo , Oxirredução
8.
Biomed Environ Sci ; 36(9): 874-879, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37803900

RESUMO

Leclercia adecarboxylata is a Gram-negative bacterium belonging to the Enterobacteriaceae family. To our knowledge, this is the first report of a carbapenem-resistant L. adecarboxylata strain isolated from a healthy newborn. The L. adecarboxylata strain isolated in this study carried four plasmids that may serve as reservoirs for antibiotic resistance genes. Plasmids 2 and 4 did not harbor any antimicrobial resistance genes. Plasmid 3 is a novel plasmid containing three resistance genes. The bla IMP gene harbored in the strain was most similar to bla IMP-79 at the nucleotide level, with a similarity of 99.4% (737/741). This case highlights the importance of considering L. adecarboxylata as a potential cause of infections in children.


Assuntos
Infecções por Enterobacteriaceae , Recém-Nascido , Criança , Humanos , Feminino , Infecções por Enterobacteriaceae/tratamento farmacológico , Infecções por Enterobacteriaceae/microbiologia , Enterobacteriaceae/genética , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Plasmídeos
9.
RSC Adv ; 13(37): 26102-26110, 2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37664210

RESUMO

Ascorbic acid is a nutritional small molecule essential to human life activities and health, playing a vital role in many physiological processes. Fresh fruits and beverages can provide abundant AA to maintain human metabolic balance. Therefore, it is of great significance to develop a nanomaterial with superior nanozyme activity for rapid and convenient detection of ascorbic acid (AA) in fruits and beverages. Herein, a dual-signal sensing platform based on UV-vis absorption and test strip chromaticity for the quantitative determination of AA is presented. The sensing platform is based on the horseradish peroxidase-like activity of Ni3V2O8 nanoflowers, which catalyzes the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) by hydrogen peroxide to the blue oxide TMB (ox TMB). The ox TMB produced by the oxidation has a characteristic absorption peak at 650 nm. In the presence of AA, the blue ox TMB is reduced to colorless TMB, and the quantitative detection of AA can be achieved by detecting the decrease in intensity of the absorption peak by UV-Vis spectrophotometry. Under the optimal experimental conditions, the sensing platform exhibited excellent sensitivity and selectivity. A wide linear range of 0.1 µM to 40 µM with a detection limit of 0.032 µM was obtained. The linear equation is ΔA = 0.02513c + 0.1164 with a correlation coefficient of 0.9979. It showed excellent properties in the detection of real samples of fruit juices and beverages, meanwhile, a method for the rapid detection of AA based on chromaticity change of test strips was constructed with high sensitivity and convenience. The linearity range for the ascorbic acid was 1-50 µM with LOD of 0.42 µM. The developed sensing platform has the capability to quickly and accurately detect ascorbic acid (AA) in fresh fruits and beverages. This proposed method offers a new and promising approach for the rapid and cost-effective detection of ascorbic acid, which has a wide range of potential applications.

10.
ACS Nano ; 17(18): 17779-17789, 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37708057

RESUMO

The development of high-performance platinum (Pt)-based electrocatalysts for the hydrogen oxidation reaction (HOR) is highly desirable for hydrogen fuel cells, but it is limited by the sluggish kinetics and severe carbon monoxide (CO) poisoning in alkaline medium. Herein, we explore a class of facet-selected Pt-nickel-indium fishbone-like nanowires (PtNiIn FNWs) featuring high-index facets (HIFs) of Pt3In skin as efficient alkaline HOR catalysts. Impressively, the optimized Pt66Ni6In28 FNWs show the highest mass and specific activities of 4.02 A mgPt-1 and 6.56 mA cm-2, 2.0/2.1 and 13.9/15.6 times larger than those of commercial PtRu/C and commercial Pt/C, respectively, along with a competitive CO-tolerance ability. Specifically, they exhibit only 6.0% current density decay after 10000 s of operation and 25.7% activity loss after 2000 s in the presence of 1000 ppm of CO. Moreover, an isotope experiment and density functional theory (DFT) calculations further prove that the unique structure and synergy among Pt, Ni, and In endow these Pt66Ni6In28 FNWs with an optimized hydrogen binding energy (HBE) and an advantageous hydroxide binding energy (OHBE), giving them excellent alkaline HOR properties. The combined construction of surface-skin and HIFs in PtNiIn FNWs will offer an available method to realize the potential applications of advanced non-PtRu-based catalysts in fuel cells and beyond.

11.
Environ Sci Technol ; 57(33): 12534-12545, 2023 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-37555746

RESUMO

The continuous electron supply for oxidant decomposition-induced reactive oxygen species (ROS) generation is the main contributor for the long-standing micropollutant oxidation in the iron-based advanced oxidation processes (AOPs). Herein, as a new class of co-catalysts, metal borides with dual active sites and preeminent conductive performance can effectively overcome the inherent drawback of Fenton-like reactions by steadily donating electrons to inactive Fe(III). Among the metal borides, tungsten boride (WB) exhibits a significant co-catalytic performance run ahead of common heterogeneous co-catalysts and exceptionally high stability. Based on qualitative and semi-quantitative tests, the hydroxyl radical, sulfate radical, and iron(IV)-oxo complex are all produced in the WB/Fe(III)/PDS system and Fe(IV)-induced methyl phenyl sulfoxide decomposition is up to 72%. Moreover, the production efficiency of ROS and relative proportions of radical and nonradical pathways change with various experimental conditions (dosages of PDS, WB, and solution pH) and water matrices. The rate-determining step of Fe(II) regeneration is greatly accelerated resulting from the synergetic effect between exposed metallic reactive sites and nonmetallic boron with reductive properties of WB. In addition, the self-dissolution of surface tungsten oxide and boron oxide leads to a renovated surface for sustainable Fe(III) reduction in long-term operations. Our discovery provides an efficient and sustainable strategy in the field of enhanced AOPs for water remediation.


Assuntos
Boro , Compostos Férricos , Compostos Férricos/química , Espécies Reativas de Oxigênio , Peróxido de Hidrogênio/química , Ferro/química , Metais , Oxirredução , Água
12.
J Hazard Mater ; 458: 131941, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37392644

RESUMO

A molecularly imprinted polymers (MIPs)-isolated AuNP-enhanced fluorescence sensor, AuNP@MIPs-CdTe QDs, was developed for highly sensitive and selective detection of oxytetracycline (OTC) in aqueous medium. The developed sensor combined the advantages of strong fluorescence signal of metal-enhanced fluorescence (MEF), high selectivity of MIPs, and stability of CdTe QDs. The MIPs shell with specific recognition served as an isolation layer to adjust the distance between AuNP and CdTe QDs to optimize the MEF system. The sensor demonstrated the detection limit as low as 5.22 nM (2.40 µg/L) for a concentration range of 0.1-3.0 µM OTC and good recovery rates of 96.0-103.0% in real water samples. In addition, high specificity recognition for OTC over its analogs was achieved with an imprinting factor of 6.10. Molecular dynamics (MD) simulation was utilized to simulate the polymerization process of MIPs and revealed H-bond formation as the mainly binding sites of APTES and OTC, and finite-difference time-domain (FDTD) analysis was employed to obtain the distribution of electromagnetic field (EM) for AuNP@MIPs-CdTe QDs. The experimental results combined with theoretical analyses not only provided a novel MIP-isolated MEF sensor with excellent detection performance for OTC but also established a theoretical basis for the development of a new generation of sensors.


Assuntos
Compostos de Cádmio , Impressão Molecular , Oxitetraciclina , Pontos Quânticos , Polímeros Molecularmente Impressos , Impressão Molecular/métodos , Pontos Quânticos/química , Compostos de Cádmio/química , Telúrio/química , Água , Limite de Detecção
13.
Chempluschem ; 88(8): e202300292, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37483159

RESUMO

The capture of carbon dioxide (CO2 ) from industrial process emissions is increasingly important for the mitigation and prevention of the disruptive effects of global warming. In this study, PAF (porous aromatic frameworks)-TPB(1,3,5-triphenylbenzene) and three-dimensional PAF-TPM (tetraphenylmethane) porphyrin-based aromatic porous materials were synthesized through the Scholl reaction. The CO2 and N2 adsorption isotherms at 273 K and 298 K were studied to determine the performance in carbon dioxide capture at flue gas conditions. There is a significant difference in the adsorption capacity of the two materials for CO2 and N2 , so they can be used for CO2 /N2 adsorption separation. PAF-TPM has better CO2 /N2 separation at low pressure (150 mbar), while PAF-TPB has the advantage of greater CO2 /N2 separation at high pressure (1 bar). It can be applied to CO2 adsorption separation at low and high pressure, respectively. In particular, PAF-TPB has a CO2 /N2 separation efficiency of up to 100.9 at 1 bar and 273 K. This work provides ideas for the design and synthesis of organic porous materials for the adsorption separation of CO2 and N2 .

14.
Artigo em Inglês | MEDLINE | ID: mdl-37458940

RESUMO

It is widely accepted that circadian rhythm disruption caused short- or long-term adverse effects on health. Although many previous studies have focused on exploration of the molecular mechanisms, there is no rapid, convenient, and non-invasive method to reveal the influence on health after circadian rhythm disruption. Here, we performed a high-resolution mass spectrometry-based data-independent acquisition (DIA) quantitative urinary proteomic approach in order to explore whether urine could reveal stress changes to those brought about by circadian rhythm disruption after sleep deprivation. After sleep deprivation, the subjects showed a significant increase in both systolic and diastolic blood pressure compared with routine sleep. More than 2000 proteins were quantified and they contained specific proteins for various organs throughout the body. And a total of 177 significantly up-regulated proteins and 68 significantly down-regulated proteins were obtained after sleep deprivation. These differentially expressed proteins (DEPs) were associated with multiple organs and pathways, which reflected widespread influences of sleep deprivation. Besides, machine learning identified a panel of five DEPs (CD300A, SCAMP3, TXN2, EFEMP1, and MYH11) that can effectively discriminate circadian rhythm disruption. Taken together, our results validate the value of urinary proteome in predicting and diagnosing the changes by circadian rhythm disruption.

15.
J Comput Biol ; 30(8): 877-888, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37471241

RESUMO

Spatial transcriptome (ST) technology provides both the spatial location and transcriptional profile of spots, as well as tissue images. ST data can be utilized to construct gene regulatory networks, which can help identify gene modules that facilitate the understanding of biological processes such as cell communication. Correlation measurement is the core basis for constructing a gene regulatory network. However, due to the high noise and sparsity in ST data, common correlation measurement methods such as the Pearson correlation coefficient (PCC) and Spearman correlation coefficient (SPCC) are not suitable. In this work, a new gene correlation measurement method called STgcor is proposed. STgcor defines vertexes as spots in a two-dimensional coordinate plane consisting of axes X and Y from the gene pair (X and Y). The joint probability density of Gaussian distribution of the gene pair (X and Y) is calculated to identify and eliminate outliers. To overcome sparsity, the degree, trend, and location of the distribution of vertexes are used to measure the correlation between gene pairs (X, Y). To validate the performance of the STgcor method, it is compared with the PCC and SPCC in a weighted coexpression network analysis method using two ST datasets of breast cancer and prostate cancer. The gene modules identified by these methods are then compared and analyzed. The results show that the STgcor method detects some special gene modules and cancer-related pathways that cannot be detected by the other two methods.


Assuntos
Neoplasias da Mama , Transcriptoma , Masculino , Humanos , Transcriptoma/genética , Redes Reguladoras de Genes , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Perfilação da Expressão Gênica/métodos
16.
Microorganisms ; 11(5)2023 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-37317299

RESUMO

An increase in the carbapenem-hydrolyzing capacity of class D ß-lactamase has been observed in strains of multiple species, posing a significant challenge to the control of antibiotic resistance. In this study, we aimed to investigate the genetic diversity and phylogenetic characteristics of new blaOXA-48-like variants derived from Shewanella xiamenensis. Three ertapenem-non-susceptible S. xiamenensis strains were identified, one isolated from the blood sample of an inpatient, the other two isolated from the aquatic environment. Phenotypic characterization confirmed that the strains were carbapenemase producers and exhibited antimicrobial resistance patterns to ertapenem, with some showing lower susceptibility to imipenem, chloramphenicol, ciprofloxacin, and tetracycline. No significant resistance to cephalosporins was observed. Sequence analysis revealed that one strain harbored blaOXA-181 and the other two strains harbored blaOXA-48-like genes, with open reading frame (ORF) similarities with blaOXA-48 ranging from 98.49% to 99.62%. The two novel blaOXA-48-like genes, named blaOXA-1038 and blaOXA-1039, respectively, were cloned and expressed in E. coli. The three OXA-48-like enzymes demonstrated significant hydrolysis activity against meropenem, and the classical ß-lactamase inhibitor had no significant inhibitory effect. In conclusion, this study demonstrated the diversity of the blaOXA gene and highlighted the emergence of novel OXA carbapenemases in S. xiamenensis. Further attention to S. xiamenensis and OXA carbapenemases is recommended for the effective prevention and control of antibiotic-resistant bacteria.

17.
Radiol Med ; 128(6): 668-678, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37277573

RESUMO

BACKGROUND: Whether Intravoxel incoherent motion (IVIM) can be used as a predictive tool of positive surgical margins (PSMs) and Gleason score (GS) upgrading in prostate cancer (PCa) patients after radical prostatectomy (RP) still remains unclear. The aim of this study is to explore the ability of IVIM and clinical characteristics to predict PSMs and GS upgrading. METHODS: A total of 106 PCa patients after RP who underwent pelvic mpMRI (multiparametric Magnetic Resonance Imaging) between January 2016 and December 2021 and met the requirements were retrospectively included in our study. IVIM parameters were obtained using GE Functool post-processing software. Logistic regression models were fitted to confirm the predictive risk factor of PSMs and GS upgrading. The area under the curve and fourfold contingency table were used to evaluate the diagnostic efficacy of IVIM and clinical parameters. RESULTS: Multivariate logistic regression analyses revealed that percent of positive cores, apparent diffusion coefficient and molecular diffusion coefficient (D) were independent predictors of PSMs (Odds Ratio (OR) were 6.07, 3.62 and 3.16, respectively), Biopsy GS and pseudodiffusion coefficient (D*) were independent predictors of GS upgrading (OR were 0.563 and 7.15, respectively). The fourfold contingency table suggested that combined diagnosis increased the ability of predicting PSMs but had no advantage in predicting GS upgrading except the sensitivity from 57.14 to 91.43%. CONCLUSIONS: IVIM showed good performance in predicting PSMs and GS upgrading. Combining IVIM and clinical factors enhanced the performance of predicting PSMs, which may contribute to clinical diagnosis and treatment.


Assuntos
Margens de Excisão , Neoplasias da Próstata , Masculino , Humanos , Gradação de Tumores , Estudos Retrospectivos , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/cirurgia , Neoplasias da Próstata/patologia , Prostatectomia/métodos
18.
Phys Chem Chem Phys ; 25(20): 14635-14641, 2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37194331

RESUMO

The electronic transport properties of two-dimensional (2D) tetragonal ZnX (X = S, Se) monolayers have been studied using density functional theory (DFT) and non-equilibrium Green's function (NEGF) methods. The gate voltage (a 5 V in particular) generally enhances the transport performance of the monolayers, which is ca. three times that without the gate voltage. It is shown that the transport properties of the Janus Zn2SeS monolayer may show a relatively good trend among the ZnX monolayers, and the Zn2SeS monolayer has the highest sensitivity to gate-voltage regulation. We also investigate the photocurrent of ZnX monolayers under linearly polarized light irradiation in the visible and near-ultraviolet regions, and the ZnS monolayer processes a maximum value of 15 a02 per photon in the near-ultraviolet region. The excellent electronic transport properties make environmentally friendly tetragonal ZnX monolayers promising for utilization in various electronic and optoelectronic devices.

19.
Gene ; 876: 147520, 2023 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-37257791

RESUMO

Toll-like receptors (TLRs) are pattern recognition receptors found on both immune and cancerous cells. Gastric cancer (GC) cells/tissues have been shown to exhibit elevated levels of TLR4. Here, we examined the role of TLR4 on autophagy and proliferation in GC cells. Real-time quantitative polymerase chain reaction (RT-qPCR) and western blot (WB) were used to determine TLR4 levels at different stages of GC cells/tissues as well as the levels of autophagy-related proteins (ARPs) and determine the underlying signaling mechanism. Proliferation was assessed via the CCK-8 assay. The protein and mRNA levels of ARPs were elucidated, followed by estimating the involved signaling pathways. Our results demonstrated that the modulation of the PI3K/AKT/mTOR pathway resulted from autophagy inhibition/induction, which was induced by the overexpression and knockdown of TLR4. Thus, TLR4 played a vital role in GC progression.


Assuntos
Proteínas Proto-Oncogênicas c-akt , Neoplasias Gástricas , Humanos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Receptor 4 Toll-Like , Neoplasias Gástricas/genética , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Linhagem Celular Tumoral , Autofagia , Proliferação de Células
20.
Front Microbiol ; 14: 1138039, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36937303

RESUMO

Streptococcus agalactiae (Group B Streptococcus, GBS) is a major cause of neonatal infections with high morbidity and mortality, and clindamycin is the main antibiotic used to treat GBS infections in patients allergic to penicillin. We aimed to analyse the antibiotic sensitivity, sequence types, serotypes, virulence factors, and antibiotic resistance mechanisms of clinically isolated clindamycin-resistant S. agalactiae and provide basic data for the treatment, prevention, and control of clinical infection of S. agalactiae. A total of 110 strains of clindamycin-resistant S. agalactiae were collected from two tertiary hospitals in Hebei, China. We performed antibiotic sensitivity tests for 11 antibiotics on these strains and whole-genome sequencing analysis. All the strains were susceptible to penicillin, ampicillin, linezolid, vancomycin, tigecycline, and quinupristin-dalfopristin. Resistance to erythromycin, levofloxacin, tetracycline, and chloramphenicol were also observed. Genome sequence analysis revealed that all strains belonged to 12 sequence types (STs) related to six cloning complexes (CCs), namely CC10, CC19, CC23, CC651, CC1, and CC17. Five serotypes were identified, including IA, IB, II, III, and V. The most prominent resistance genes were mreA (100%) and ermB (81.8%). Furthermore, cfb, cylE, pavA and the gene cluster related to the pili were 100% present in all strains, followed by lmb (95.5%) and srr1 (67.2%). This study found that clindamycin-resistant S. agalactiae showed polymorphisms in molecular types and serotypes. Furthermore, multiple virulence factor genes have been identified in their genomes.

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