Variations in Surface Morphologies, Properties, and Electrochemical Responses to Nitro-Analyte by Controlled Electropolymerization of Thiophene Derivatives

Herein, we reported the fabrication of conjugated microporous polymer (CMP) films based on three thiophene derivatives using a one-step templateless electropolymerization in dichloromethane without any surfactants. The formation of hydrophilic or hydrophobic films with specific morphology is a comprehensive result of the polymerization sites in each monomer, the polymerization rate, and the gas bubble produced in situ during the polymerization process, which can be easily controlled by the experimental conditions, such as electropolymerization method, electrolyte, and “trace water” existed in the organic solvent. Moreover, the electrochemical reduction of metronidazole as a prototypical nitro-analyte at CMP-modified glassy carbon (GC) electrode shows remarkably increased current response compared to nonmodified GC electrode. The process is demonstrated to be typical adsorption-controlled, and the hydrophobic surface of the electrode coating film is more favorable to the absorption and thus reduction of metronidazole. This work provides a new perspective and a breakthrough point for the application of CMPs in the electrochemical sensors

Characteristics of cases with uterine fibroids and controls and odds ratios of uterine fibroids according to subclinical atherogenic and cardiovascular risk parameters.

a<p>Age-adjusted.</p>b<p>Adjusted for age (continuous), BMI (<21.94, 21.94–24.41, >24.41), age at menarche (≤14, 15–16, ≥17, missing), gravity (0, 1, 2, 3, ≥4) and age at last birth (≤24, 25–29, ≥30, missing).</p>c<p>Adjusted for age (continuous), age at menarche (≤14, 15–16, ≥17, missing), gravity (0, 1, 2, 3, ≥4) and age at last birth (≤24, 25–29, ≥30, missing).</p>d<p>Adjusted for adjusted for age (continuous), BMI (<21.94, 21.94–24.41, >24.41), age at menarche (≤14, 15–16, ≥17, missing), gravity (0, 1, 2, 3, ≥4), age at last birth (≤24, 25–29, ≥30, missing), folate (<8.55, 8.55–11.27, >11.27) and vitamin B12 (<433.57, 433.57–612.10, >612.10).</p

Characteristics of cases with uterine fibroids and controls and unadjusted odds ratios for uterine fibroids according to selected characteristics.

a<p>Data were available for 71.9% of cases and 91.8% of controls.</p>b<p>Data were available for 87.2% of cases and 87.9% of controls.</p

Classification of Molecular Binding Traces for Dynamic Single-Molecule Sensing

Interference from nonspecific binding imposes a fundamental limit in the sensitivity of biosensors that is dependent on the affinity and specificity of the available sensing probes. The dynamic single-molecule sensing (DSMS) strategy allows ultrasensitive detection of biomarkers at the femtomolar level by identifying specific binding according to molecular binding traces. However, the accuracy in classifying binding traces is not sufficient from separate features, such as the bound lifetime. Here, we establish a DSMS workflow to improve the sensitivity and linearity by classifying molecular binding traces in surface plasmon resonance microscopy with multiple kinetic features. The improvement is achieved by correlation analysis to select key features of binding traces, followed by unsupervised k-clustering. The results show that this unsupervised classification approach improves the sensitivity and linearity in microRNA (hsa-miR155-5p, hsa-miR21-5p, and hsa-miR362-5p) detection to achieve a limit of detection at the subfemtomolar level

Multivariable model of best predictors according to subclinical atherogenic and cardiovascular risk parameters for UF in the overall and hysterectomy-confirmed groups.

a<p>Adjusted for age (continuous), BMI (<21.94, 21.94–24.41, >24.41), age at menarche (≤14, 15–16, ≥17, missing), gravity (0, 1, 2, 3, ≥4) and age at last birth (≤24, 25–29, ≥30, missing).</p

Label-Free Simultaneous Analysis of Fe(III) and Ascorbic Acid Using Fluorescence Switching of Ultrathin Graphitic Carbon Nitride Nanosheets

A simple chemical oxidation and ultrasound exfoliation method has been developed to synthesize the two-dimensional and ultrathin-layer materialsgraphitic carbon nitride nanosheets (g-C₃N₄ NNs). The prepared ultrathin g-C₃N₄ NNs display strong fluorescence and stability, including good photostability and excellent antisalt ability. Herein, a new “on–off–on” fluorescent switching sensor is designed. The iron ion (Fe³⁺) has an ultrasensitive response to quench the fluorescence of g-C₃N₄ NNs based on the synergistic effect between inner filter effect and photoinduced electron transfer. The linear limit for Fe³⁺ was from 0.05 to 30 μmol L^–1 with a detection limit of 0.018 μmol L^–1. Meanwhile, the fluorescence of g-C₃N₄ NNs can recover through the redox reaction between Fe³⁺ and ascorbic acid (AA). In addition, the linear range for AA was from 0.2 to 112.5 μmol L^–1 with a 0.086 μmol L^–1 detection limit. The proposed method exhibited rapid response, excellent selectivity, wide detection range, and low detection limit for simultaneous analysis of Fe³⁺ and AA, and it was applied for the determination of Fe³⁺ and AA in water sample and human serum with satisfactory results

Reduced Iron-Containing Clay Minerals as Antibacterial Agents

Previous work documented the general antibacterial mechanism of iron containing clays that involved hydroxyl radical (•OH) production from soluble Fe²⁺, and attack of cell membrane and intracellular proteins. Here we explore the role of clay structural Fe­(II) in •OH production at near neutral pH and identify a lipid involved in the antibacterial process. Structural Fe­(III) in nontronite NAu-2 was reduced (rNAu-2) and <i>E. coli</i>, a model bacterium, was exposed to rNAu-2 in oxic suspension. The antibacterial activity of rNAu-2 was dependent on pH and Fe­(II) concentration, where <i>E. coli</i> were completely killed at pH 6, but survived at pH 7 and 8. In the presence of a •OH scavenger or in anaerobic atmosphere, <i>E. coli</i> survived better, suggesting that cell death may be caused by •OH generated from oxidation of structural Fe­(II) in rNAu-2. In-situ imaging revealed damage of a membrane lipid, cardiolipin, in the polar region of <i>E. coli</i> cells, where reactive oxygen species and redox-active labile Fe were enriched. Our results advance the previous antibacterial model by demonstrating that the structural Fe­(II) is the primary source of •OH, which damages cardiolipin, triggers the influx of soluble Fe²⁺ into the cell, and ultimately leads to cell death

DataSheet1.PDF

<p>Purpose: To present a new modified tri-exponential model for diffusion-weighted imaging (DWI) to detect the strictly diffusion-limited compartment, and to compare it with the conventional bi- and tri-exponential models.</p><p>Methods: Multi-b-value diffusion-weighted imaging (DWI) with 17 b-values up to 8,000 s/mm² were performed on six volunteers. The corrected Akaike information criterions (AICc) and squared predicted errors (SPE) were calculated to compare these three models.</p><p>Results: The mean f₀ values were ranging 11.9–18.7% in white matter ROIs and 1.2–2.7% in gray matter ROIs. In all white matter ROIs: the AICcs of the modified tri-exponential model were the lowest (p < 0.05 for five ROIs), indicating the new model has the best fit among these models; the SPEs of the bi-exponential model were the highest (p < 0.05), suggesting the bi-exponential model is unable to predict the signal intensity at ultra-high b-value. The mean ADC_very−slow values were extremely low in white matter (1–7 × 10⁻⁶ mm²/s), but not in gray matter (251–445 × 10⁻⁶ mm²/s), indicating that the conventional tri-exponential model fails to represent a special compartment.</p><p>Conclusions: The strictly diffusion-limited compartment may be an important component in white matter. The new model fits better than the other two models, and may provide additional information.</p

Spearman's correlation coefficients between the EZSCAN value and indices of arterial stiffness.

<p>cSBP, central systolic blood pressure; baPWV, brachial-ankle pulse wave velocity; ABI, ankle-brachial index.</p><p>^***<i>P</i><0.0001; ^**<i>P</i><0.01; ^*<i>P</i><0.05.</p

Prevalence of NGT (solid bars) and IGR (open bars) across EZSCAN value quartiles.

<p>Prevalence of NGT (solid bars) and IGR (open bars) across EZSCAN value quartiles.</p