Studies on competitive adsorption characteristics of bisphenol A and 17α-ethinylestradiol on thermoplastic polyurethane by site energy distribution theory.

Compound pollution of microplastics and estrogens is a growing ecotoxicological problem in aquatic environments. The adsorption isothermal properties of bisphenol A (BPA) and 17α-ethinyl estradiol (EE2) on polyamide (TPU) in monosolute and bisolute systems were studied. Under the same adsorption concentration (1-4 mg L-1), EE2 had a greater adsorption capacity than BPA in the monsolute system. Compared to the energy distribution features of the adsorption sites of EE2 and BPA, the BPA adsorption sites were located in the higher energy area and were more evenly distributed than those of EE2, while the quantity of BPA adsorption sites was less than that of EE2. In the bisolute system, the average site energy, site energy inhomogeneity, and adsorption site numbers of BPA increased by 1.674, -17.166, and 16.793%, respectively. In comparison, the average site energy, site energy inhomogeneity, and adsorption sites numbers of EE2 increased by 2.267, 4.416, and 8.585%, respectively. The results showed that BPA and EE2 had a cooperative effect on the competitive adsorption of TPU. XPS analysis showed that BPA and EE2 had electron transfer on TPU, although the chemisorption effects and hydrogen bonds between BPA and TPU were more significant. Comparing the changes in the relative functional group content of TPU in monosolute and bisolute systems, BPA and EE2 were synergistically absorbed on TPU. This study can provide a theoretical reference for the study of competitive adsorption between coexisting organic pollutants.

The severity of portal hypertension by a non-invasive assessment: acoustic structure quantification analysis of liver parenchyma.

BACKGROUND: Acoustic structure quantification (ASQ) has been applied to evaluate liver histologic changes by analyzing the speckle pattern seen on B-mode ultrasound. We aimed to assess the severity of portal hypertension (PHT) through hepatic ultrasonography. METHODS: Sixty patients diagnosed with PHT and underwent surgical treatment with portosystemic shunts were enrolled. Portal pressure (PP) was measured intraoperatively. Patients were divided into subgroups according to the severity of gastroesophageal varices and Child-Pugh class. Three difference ratio (Cm2) values on ASQ histogram mode were analyzed for their relationships with PP, degree of gastroesophageal varices and Child-Pugh liver function. Thirty healthy volunteers matched with the patients for gender and age were enrolled as controls. Comparisons among groups and correlation of the parameters with PP were analyzed. Area under the receive operating characteristic curve was used to evaluate the predicting value of ASQ parameters. RESULTS: In the patients, the ASQ parameters peak Cm2 (Cm2max), mean Cm2 (Cm2mean) and the highest occurred Cm2 value of the obtained red curve (RmaxCm2) were all greatly increased (P < 0.0001, P < 0.0001, P = 0.027). Multiple comparisons indicated that, regardless of Child-Pugh class and degree of gastroesophageal varices, the patients had significantly increased Cm2max and Cm2mean compared with the controls (all P < 0.0001). No differences among subgroups were observed. Cm2max was significantly statistically correlated with PP (r = 0.3505, P < 0.01), degree of varices (r = 0.4998, P < 0.0001). Youden's index for Cm2max with a cut-off value of 140.3 for predicting the presence of PHT, gastroesophageal varices and liver function equal to or worse than Child-Pugh class B were 0.8, 0.91 and 0.84, respectively. CONCLUSIONS: ASQ analysis of ultrasonographic images may have a role in the evaluation of the severity of PHT by detecting liver histologic changes in the speckle pattern caused by cirrhosis.

Single-Nucleotide Resolution Analysis of 5-Hydroxymethylcytosine in DNA by Enzyme-Mediated Deamination in Combination with Sequencing.

The report of the existence of 5-hydroxymethylcytosine (hm5C) in mammalian genomes is a milestone discovery. hm5C is now generally viewed as the sixth base of DNA with important functions on epigenetic regulation. The in-depth investigation of the biological functions of hm5C requires elucidating the distribution patterns of hm5C in genomes, better in single-nucleotide resolution. It was reported that the cytosine deaminases of the APOBEC (apolipoprotein B mRNA-editing catalytic polypeptide-like) family are nucleic acid editing enzymes and can deaminate cytosine (C) to form uracil (U). Particularly, a subfamily of APOBEC (APOBEC3A) can efficiently deaminate both C and 5-methylcytosine (m5C). In the current study, we identified that APOBEC3A protein can effectively deaminate C, m5C, and hm5C but shows no observable deamination activity toward glycosylated hm5C (ß-glucosyl-5-hydroxymethyl-2'-deoxycytidine, ghm5C) by using the restriction enzyme-based assay and liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) analysis. By virtue of the differential deamination activity of APOBEC3A toward C, m5C, and ghm5C in conjugation with sequencing, we developed the single-nucleotide resolution analysis of hm5C in DNA. In this analytical strategy, the original C and m5C in DNA will be deaminated by APOBEC3A to form U and thymine (T), both of which will read as T during sequencing, while ghm5C is resistant to deamination and will read as C during sequencing. Therefore, the remaining C in the sequence context only could come from original hm5C, which offers the single-nucleotide resolution analysis of hm5C in DNA. This APOBEC3A-mediated deamination sequencing (AMD-seq) is straightforward and involves no bisulfite treatment, which avoids the substantial degradation of DNA. Future application of this strategy can be performed for the reliable mapping of hm5C in genome-wide scale at the single-nucleotide resolution.

Artificial neural network aided non-invasive grading evaluation of hepatic fibrosis by duplex ultrasonography.

BACKGROUND: Artificial neural networks (ANNs) are widely studied for evaluating diseases. This paper discusses the intelligence mode of an ANN in grading the diagnosis of liver fibrosis by duplex ultrasonogaphy. METHODS: 239 patients who were confirmed as having liver fibrosis or cirrhosis by ultrasound guided liver biopsy were investigated in this study. We quantified ultrasonographic parameters as significant parameters using a data optimization procedure applied to an ANN. 179 patients were typed at random as the training group; 60 additional patients were consequently enrolled as the validating group. Performance of the ANN was evaluated according to accuracy, sensitivity, specificity, Youden's index and receiver operating characteristic (ROC) analysis. RESULTS: 5 ultrasonographic parameters; i.e., the liver parenchyma, thickness of spleen, hepatic vein (HV) waveform, hepatic artery pulsatile index (HAPI) and HV damping index (HVDI), were enrolled as the input neurons in the ANN model. The sensitivity, specificity and accuracy of the ANN model for quantitative diagnosis of liver fibrosis were 95.0%, 85.0% and 88.3%, respectively. The Youden's index (YI) was 0.80. CONCLUSIONS: The established ANN model had good sensitivity and specificity in quantitative diagnosis of hepatic fibrosis or liver cirrhosis. Our study suggests that the ANN model based on duplex ultrasound may help non-invasive grading diagnosis of liver fibrosis in clinical practice.

Noninvasive stiffness assessment of the human lens nucleus in patients with anisometropia using an ultrasound elastography system.

AIM: To investigate the significance of ultrasound elastography for evaluating stiffness of the human lens nucleus in patients with anisometropia. METHODS: A total of 14 patients (28 eyes) with anisometropia were enrolled. The difference in refractive status between two eyes ≥-4.0 diopters (D) and the difference in axial length (AL) of the eyes was ≥3 mm. There were 5 males and 9 females with an average age of 62±3.3y. The test data of the long AL eye of each patient was included in group A (14 eyes), and test data of the eye with relative short AL was included in group B. Lens nuclear stiffness was measured with free-hand qualitative elastography by independent operators. Strain gray scale and color-coded elastography maps were recorded. In each case, three consecutive measurements were performed and strain ratio was used for statistical analysis. Photograph and sectional view of the lens were analyzed and archived by anterior segment image. RESULTS: In the long AL group, the strain rate in the nucleus of the lens was 0.16%±0.08%; in the short AL group, the strain rate in the nucleus of the lens was 0.54%±0.16%. Independent sample t-test analyses showed that the long AL group lens had a significantly smaller nuclear strain rate than the relatively short AL group, P<0.05. CONCLUSION: The relationship between human lens stiffness and different AL is demonstrated by ultrasound elastography. The long AL is associated with lower strain ratio and less resilience of the lens.

Location analysis of 8-oxo-7,8-dihydroguanine in DNA by polymerase-mediated differential coding.

Accumulating lines of evidence indicate that reactive oxygen species (ROS) are important signalling molecules for various cellular processes. 8-Oxo-7,8-dihydroguanine (OG) is a prominent oxidative modification formed in DNA by ROS. Recently, it has been proposed that OG may have regulatory and possibly epigenetic-like properties in modulating gene expression by interfering with transcription components or affecting the formation of G-quadruplex structures. Deciphering the molecular mechanisms of OG on regulation of gene expression requires uncovering the location of OG on genome. In the current study, we characterized two commercially available DNA polymerases, Bsu DNA polymerase (Bsu Pol) and Tth DNA polymerase (Tth Pol), which can selectively incorporate adenine (A) and cytosine (C) opposite OG, respectively. By virtue of the differential coding properties of Bsu Pol and Tth Pol that can faithfully or error-prone copy a DNA strand carrying OG, we achieved quantitative and single-base resolution analysis of OG in synthesized DNA that carries OG as well as in the G-rich telomeric DNA from HeLa cells. In addition, the parallel analysis of the primer extension products with Bsu Pol and Tth Pol followed by sequencing provided distinct detection of OG in synthesized DNA. Future application of this approach will greatly increase our knowledge of the chemical biology of OG with respect to its epigenetic-like regulatory roles.