ABSTRACT
The electrochemical corrosion of Ti surfaces is significantly affected by O adsorption, yet the underlying mechanisms remain unexplored. Herein, density functional theory calculations are employed to examine the adsorption energies, structural properties, electronic structures, and thermodynamic stability of atomic O on Ti(0001) surfaces during initial oxidation. Additionally, the impact of O adsorption on Ti dissolution is assessed by introducing a Ti vacancy on the Ti(0001) surface. The passivation of the Ti(0001) surface is predominantly ascribed to the robust adsorption of O atoms. The thermodynamic results reveal that bulk TiO2 easily forms at 300 K, which explains the spontaneous passivation of the Ti(0001) surface. The formation of an O monolayer on the Ti(0001) surface increases the work function (Φ), positively shifting the equilibrium potential and reducing the corrosion rate. The surface vacancy formation energy of Ti on the Ti(0001)/O surface surpasses that on the clean surface. The electrode potential shift for a Ti atom dissolving from the Ti(0001)/O surface is positive, indicating that oxidation impedes the formation of Ti vacancies, rendering Ti atoms less soluble. This study enhances our comprehension of the corrosion mechanism in Ti metal.
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BACKGROUND: The increasing problem of bacterial resistance, particularly with quinolone-resistant Escherichia coli (QnR eco) poses a serious global health issue. METHODS: We collected data on QnR eco resistance rates and detection frequencies from 2014 to 2021 via the China Antimicrobial Resistance Surveillance System, complemented by meteorological and socioeconomic data from the China Statistical Yearbook and the China Meteorological Data Service Centre (CMDC). Comprehensive nonparametric testing and multivariate regression models were used in the analysis. RESULT: Our analysis revealed significant regional differences in QnR eco resistance and detection rates across China. Along the Hu Huanyong Line, resistance rates varied markedly: 49.35 in the northwest, 54.40 on the line, and 52.30 in the southeast (P = 0.001). Detection rates also showed significant geographical variation, with notable differences between regions (P < 0.001). Climate types influenced these rates, with significant variability observed across different climates (P < 0.001). Our predictive model for resistance rates, integrating climate and healthcare factors, explained 64.1% of the variance (adjusted R-squared = 0.641). For detection rates, the model accounted for 19.2% of the variance, highlighting the impact of environmental and healthcare influences. CONCLUSION: The study found higher resistance rates in warmer, monsoon climates and areas with more public health facilities, but lower rates in cooler, mountainous, or continental climates with more rainfall. This highlights the strong impact of climate on antibiotic resistance. Meanwhile, the predictive model effectively forecasts these resistance rates using China's diverse climate data. This is crucial for public health strategies and helps policymakers and healthcare practitioners tailor their approaches to antibiotic resistance based on local environmental conditions. These insights emphasize the importance of considering regional climates in managing antibiotic resistance.
Subject(s)
Escherichia coli Proteins , Quinolones , Escherichia coli , China/epidemiology , Drug Resistance, Bacterial , Anti-Bacterial Agents/pharmacologyABSTRACT
The computational spectrometer has significant potential for portable in situ applications. Encoding and reconstruction are the most critical technical procedures. In encoding, the random mass production and selection method lacks quantitative designs which leads to low encoding efficiency. In reconstruction, traditional spectrum reconstruction algorithms such as matching tracking and gradient descent demonstrate disadvantages like limited accuracy and efficiency. In this paper, we propose a new lightweight convolutional neural network called the wide-spectrum encoding and reconstruction neural network (WER-Net), which includes optical filters, quantitative spectral transmittance encoding, and fast spectral reconstruction of the encoded spectral information. The spectral transmittance curve obtained by WER-net can be fabricated through the inverse design network. The spectrometer developed based on WER-net experimentally demonstrates that it can achieve a 2-nm high resolution. In addition, the spectral transmittance encoding curve trained by WER-Net has also achieved good performance in other spectral reconstruction algorithms.
Subject(s)
Algorithms , Neural Networks, ComputerABSTRACT
Many proposals for exploring topological quantum computation are based on superconducting quantum devices constructed on materials with strong spin-orbit coupling (SOC). For these devices, full control of both the magnitude and the spatial distribution of the supercurrent is highly demanded, but has been elusive up to now. We constructed a proximity-type Josephson junction on nanoplates of Bi2O2Se, a new emerging semiconductor with strong SOC. Through electrical gating, we show that the supercurrent can be fully turned ON and OFF, and its real-space pathways can be configured either through the bulk or along the edges. Our work demonstrates Bi2O2Se as a promising platform for constructing multifunctional hybrid superconducting devices as well as for searching for topological superconductivity.
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PURPOSE: Polymyxin B, with its unique structure and mechanism of action, has emerged as a key therapeutic agent against Gram-negative bacteria. The study aims to explore potential factors to influence its effectiveness and safety. METHODS: A model-based meta-analysis of 96 articles was conducted, focusing on factors like dosage, bacterial species, and combined antibiotic therapy. The analysis evaluated mortality rates and incidence rate of renal dysfunction, also employing parametric survival models to assess 30-d survival rates. RESULTS: In the study involving 96 articles and 9716 patients, polymyxin B's daily dose showed minimal effect on overall mortality, with high-dose group mortality at 33.57% (95% confidence intervals [CI]: 29.15-38.00) compared to the low-dose group at 35.44% (95% CI: 28.99-41.88), P = 0.64. Mortality significantly varied by bacterial species, with Pseudomonas aeruginosa infections at 58.50% (95% CI: 55.42-63.58). Monotherapy exhibited the highest mortality at 40.25% (95% CI: 34.75-45.76), P < 0.01. Renal dysfunction was more common in high-dose patients at 29.75% (95% CI: 28.52-30.98), with no significant difference across antibiotic regimens, P = 0.54. The 30-d overall survival rate for monotherapy therapy was 63.6% (95% CI: 59.3-67.5) and 70.2% (95% CI: 64.4-76.2) for association therapy with ß-lactam drugs. CONCLUSIONS: The dosage of polymyxin B does not significantly change death rates, but its effectiveness varies based on the bacterial infection. Certain bacteria like P. aeruginosa are associated with higher mortality. Combining polymyxin B with other antibiotics, especially ß-lactam drugs, improves survival rates. Side effects depend on the dose, with lower doses being safer. These findings emphasize the importance of customizing treatment to balance effectiveness and safety.
Subject(s)
Anti-Bacterial Agents , Gram-Negative Bacterial Infections , Polymyxin B , Polymyxin B/therapeutic use , Polymyxin B/adverse effects , Polymyxin B/administration & dosage , Humans , Gram-Negative Bacterial Infections/drug therapy , Gram-Negative Bacterial Infections/mortality , Gram-Negative Bacterial Infections/microbiology , Anti-Bacterial Agents/therapeutic use , Anti-Bacterial Agents/adverse effects , Gram-Negative Bacteria/drug effects , Treatment Outcome , Survival AnalysisABSTRACT
BACKGROUND: The cyclin-dependent kinase 4 (CDK4) interacts with its canonical and non-canonical substrates modulating the cell cycle in tumor cells. However, the potential substrates and the beyond-cell-cycle-regulated functions of CDK4 in colon cancer (CC) are still unknown. Hernandezine (HER) is previously verified to induce G0/G1 phase arrest and autophagic cell death in human cancer cells, which implies that HER might target G0/G1 phase-related proteins, including CDK4. PURPOSE: The present study tried to investigate the glycolytic metabolism and oxidative stress functions of CDK4 in colon cancer. Furthermore, the inhibitory effects and potential binding sites of HER on CDK4, as well as its anti-tumor activity were investigated in CC cells. METHODS: The mass spectrometry assay was performed to identify potential endogenous substrates of CDK4 and the correlation between glycolytic metabolic rate and CDK4 level in COAD patient tissues. Meanwhile, after inhibiting the activity or the expression of CDK4, the binding capacity of CDK4 to PKM2 and NRF2 and the latter two protein distributions in cytoplasm and nucleus were detected in CC cells. In vitro, the regulatory effects of the CDK4-PKM2-NRF2 axis on glycolysis and oxidative stress were performed by ECAR, OCR, and ROS assay. The inhibitory effect of HER on CDK4 activity was explored in CC cells and the potential binding sites were predicted and testified in vitro. Furthermore, tumor growth inhibition of HER by suppressing the CDK4-PKM2-NRF2 axis was also investigated in vitro and in vivo. RESULTS: PKM2 and NRF2 were identified as endogenous substrates of CDK4 and, high-expressed CDK4 was associated with low-level glycolysis in COAD. In vitro, inactivated CDK4 facilitated CDK4-PKM2-NRF2 complex formation which resulted in 1) inhibited PKM2 activity and retarded the glycolytic rate; 2) cytoplasm-detained NRF2 failed to transcript anti-oxidative gene expressions and induced oxidant stress. Additionally, as a CDK4 inhibitor, HER developed triple anti-tumor effects including induced G0/G1 phase arrest, suppressed glycolysis, and disrupted the anti-oxidative capacity of CC cells. CONCLUSION: The results first time revealed that CDK4 modulated glycolytic and anti-oxidative capacity of CC cells via bound to its endogenous substrates, PKM2 and NRF2. Additionally, 140Asp145Asn amino acid sites of CDK4 were potential targets of HER. HER exerts anti-tumor activity by inhibited the activity of CDK4, promoted the CDK4-PKM2-NRF2 complex formation in the CC cells.
Subject(s)
Carrier Proteins , Colonic Neoplasms , Cyclin-Dependent Kinase 4 , Membrane Proteins , NF-E2-Related Factor 2 , Thyroid Hormone-Binding Proteins , Thyroid Hormones , NF-E2-Related Factor 2/metabolism , Humans , Cyclin-Dependent Kinase 4/metabolism , Colonic Neoplasms/drug therapy , Colonic Neoplasms/metabolism , Animals , Membrane Proteins/metabolism , Thyroid Hormones/metabolism , Cell Line, Tumor , Carrier Proteins/metabolism , Glycolysis/drug effects , Mice , Oxidative Stress/drug effects , Mice, Nude , Mice, Inbred BALB C , FemaleABSTRACT
Introduction: The application of voriconazole in patients with liver dysfunction lacks pharmacokinetic data. In previous study, we proposed to develop voriconazole dosing regimens for these patients according to their total bilirubin, but the regimens are based on Monte Carlo simulation and has not been further verified in clinical practice. Besides, there are few reported factors that significantly affect the efficacy of voriconazole. Methods: We collected the information of patients with liver dysfunction hospitalized in our hospital from January 2018 to May 2022 retrospectively, including their baseline information and laboratory data. We mainly evaluated the efficacy of voriconazole and the target attainment of voriconazole trough concentration. Results: A total of 157 patients with liver dysfunction were included, from whom 145 initial and 139 final voriconazole trough concentrations were measured. 60.5% (95/157) of patients experienced the adjustment of dose or frequency. The initial voriconazole trough concentrations were significantly higher than the final (mean, 4.47 versus 3.90 µg/mL, p = 0.0297). Furthermore, daily dose, direct bilirubin, lymphocyte counts and percentage, platelet, blood urea nitrogen and creatinine seven covariates were identified as the factors significantly affect the voriconazole trough concentration. Binary logistic regression analysis revealed that the lymphocyte percentage significantly affected the efficacy of voriconazole (OR 1.138, 95% CI 1.016-1.273), which was further validated by the receiver operating characteristic curve. Conclusion: The significant variation in voriconazole trough concentrations observed in patients with liver dysfunction necessitates caution when prescribing this drug. Clinicians should consider the identified factors, particularly lymphocyte percentage, when dosing voriconazole in this population.