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Although chlorobromoisocyanuric acid has been widely used in agriculture, its deleterious toxicity on aquatic organisms remains rare. In this study, zebrafish were exposed to chlorobromoisocyanuric acid (0, 30, 40, and 50 mg/L) from 10 to 96 h post‐fertilization (hpf). We found a significant reduction in immune cell numbers (neutrophils and macrophages) and the area of thymus at 96 hpf. The expression of immune‐related genes and pro‐inflammatory cytokines genes were upregulated. Besides, chlorobromoisocyanuric acid triggered neutrophils cell apoptosis. The mRNA and protein levels of pro‐apoptotic p53 pathway and the Bax/Bcl‐2 ratio further indicated the underlying mechanism. Furthermore, the oxidative stress was observed that the accumulation of reactive oxygen species and malondialdehyde significantly increased. Subsequently, the antioxidant agent astaxanthin significantly attenuated the level of oxidative stress and the dysregulation of inflammatory response. In summary, our results showed that chlorobromoisocyanuric acid induced developmental defects and immunotoxicity of zebrafish, partly owing to oxidative stress and cell apoptosis. [ABSTRACT FROM AUTHOR]

When the traditional dark channel prior (DCP) algorithm is used for image defogging, it faces some problems such as unsatisfactory restoration of the target edge details, distortion in large‐scale and high‐brightness sky regions. To solve these problems, this paper proposes an improved dark channel defogging algorithm based on the HSI colour space, named the IDCP algorithm. First, an asymmetric mean filter window is used to obtain the modified dark channel image to improve the grey value mutation in the traditional dark channel image. Based on this work, an improved global atmospheric transmittance calculation method is proposed, which effectively improves the inapplicability of the dark channel prior in large‐scale and high‐brightness sky regions. Finally, the Laplacian operator is used to sharpen the image to enhance the target edge information. Simulation results show that the proposed algorithm can effectively solve the distortion phenomenon caused by the traditional DCP algorithm when handling large‐scale and high‐brightness sky regions, improve the target edge details, and restore the true colour of the image scene. [ABSTRACT FROM AUTHOR]

Purpose: To develop a fully automated vessel wall (VW) analysis workflow (fully automated and robust analysis technique for popliteal artery evaluation, FRAPPE) on the popliteal artery in standardized knee MR images. Methods: Popliteal artery locations were detected from each MR slice by a deep neural network model and connected into a 3D artery centerline. Vessel wall regions around the centerline were then segmented using another neural network model for segmentation in polar coordinate system. Contours from vessel wall segmentations were used for vascular feature calculation, such as mean wall thickness and wall area. A transfer learning and active learning framework was applied in training the localization and segmentation neural network models to maintain accuracy while reducing manual annotations. This new popliteal artery analysis technique (FRAPPE) was validated against manual segmentation qualitatively and quantitatively in a series of 225 cases from the Osteoarthritis Initiative (OAI) dataset. Results: FRAPPE demonstrated high accuracy and robustness in locating popliteal arteries, segmenting artery walls, and quantifying arterial features. Qualitative evaluations showed 1.2% of slices had noticeable major errors, including segmenting the wrong target and irregular vessel wall contours. The mean Dice similarity coefficient with manual segmentation was 0.79, which is comparable to inter‐rater variations. Repeatability evaluations show most of the vascular features have good to excellent repeatability from repeated scans of same subjects, with intra‐class coefficient ranging from 0.80 to 0.98. Conclusion: This technique can be used in large population‐based studies, such as OAI, to efficiently assess the burden of atherosclerosis from routine MR knee scans. [ABSTRACT FROM AUTHOR]

The application of fluorescent method to metal ions detection features high sensitivity, simple operation and real‐time monitoring. A 2,7‐dihydroxynaphthalene‐functionalized dimethyl glycoluril (called clip 1) was synthesized, using a relatively simple method. And it is fully characterized by 1H NMR, 13C NMR, HR‐MS and single crystal X‐ray diffraction. The recognition properties of molecular clip 1 were analyzed systematically toward several metal ions using fluorescence spectroscopy, and it was found that molecular clip 1 is selective and sensitive to Fe3+. At the same time, the clip 1 shows good anti‐interference ability when other metal ions existed. The limit detection of Fe3+ is 3×10−7M. The fluorescence of clip 1 was quenched apparently by Fe3+, which was speculated to be caused by ligand–metal charge transfer mechanism (LMCT). As a new fluorescence probe for Fe3+ ion, it may expanded the application of glycoluril molecular clips. [ABSTRACT FROM AUTHOR]

Impaired orthostatic blood pressure (BP) stabilization is prevalent in patients with chronic kidney disease (CKD) and is associated with adverse outcomes. We aimed to test the hypothesis that reduced hemoglobin is an important contributor to orthostatic intolerance in CKD in the present study. This study included 262 patients with non-dialysis-dependent CKD. Seated and standing BP was measured, and orthostatic BP reduction was calculated for both systolic BP (∆ SBP) and diastolic BP (∆ DBP). The association between orthostatic BP reduction and hemoglobin was determined by multiple linear regression models. We also performed mediation analysis to test to what extent the effect of renal dysfunction on impaired orthostatic BP stabilization can be explained by reduced hemoglobin. The mean age of the patients was 57.7 (±14.5) years, and 61.5% were male. Both ∆ SBP and ∆ DBP correlated negatively with estimated glomerular filtration rate (eGFR). With adjustment for age and sex, hemoglobin level was negatively associated with ∆ SBP (β = -1.4, SE = 0.4, P < .001) and ∆ DBP (β = -0.6, SE = 0.2, P = .009). The associations remained significant with further adjustment for additional covariates. When eGFR was introduced as a covariate, it did not eliminate the significance (both P < .05). The associations remained essentially unchanged in a sensitivity analysis excluding those with concurrent erythropoietin use. Mediation analysis demonstrated that reduced hemoglobin accounted for 35.4% (P = .004) of the effect of eGFR on ∆ SBP and 47.7% (P = .032) on ∆ DBP. Our study suggests that reduced hemoglobin is a potentially important contributor to the development of orthostatic hypotension in CKD. [ABSTRACT FROM AUTHOR]

A new glycoluril derivative‐1H, 4H, 5H, 8H‐2, 3a, 4a, 6, 7a, 8a‐hexaazacyclopenta[def]fluorene‐4, 8‐dione, hexahydro‐2, 6‐bis(phenylmethyl) (3) is strategically designed and synthesized through the reaction between glycoluril, formaldehyde and benzylamine with the optimized molar ratio of 1:6:2. Compound 3 is fully characterized by 1H NMR, 13C NMR, IR, MS and X‐ray single crystal diffraction. Reduction of compound 3 delivers a potential precursor‐imidazo[4, 5‐d]imidazole, octahydro‐hexahydro‐2, 6‐bis(phenylmethyl) (4) for the synthesis of novel nitramine explosives (i.e. bicyclo‐HMX and bi‐RDX). The nitration and hydrolysis of compound 4 are investigated in detail and three ring‐opened molecules N, 2, 4‐trinitro‐benzenemethanamine (8a), N, 2‐dinitro‐benzenemethanamine (8b) and N‐methylene‐benzenemethanamine (9) are obtained. The synthesis, X‐ray crystal structure, hydrolysis, nitrolysis of two potential precursors for the preparation of nitramine explosives (bicycle‐HMX and bi‐RDX) are reported. [ABSTRACT FROM AUTHOR]

Abstract: We designed and synthesized a “hybrid” molecular container 1, which is structurally related to both cucurbit[n]uril (CB[n]) and pillar[n]arene type receptors. Receptor 1 was fully characterized by 1H NMR, 13C NMR, IR, MS and X‐ray single crystal diffraction. The self‐association behavior, host–guest recognition properties of 1, and the [salt] dependence of Ka were investigated in detail by 1H NMR and isothermal titration calorimetry (ITC). Optical transmittance and TEM measurements provide strong evidence that receptor 1 undergoes co‐assemble with amphiphilic guest C10 in water to form supramolecular bilayer vesicles (diameter 25.6±2.7 nm, wall thickness ≈3.5 nm) that can encapsulate the hydrophilic anticancer drug doxorubicin (DOX) and the hydrophobic dye Nile red (NR). The release of encapsulated DOX or NR from the vesicles can be triggered by hexamethonium (8 c) or spermine (10) which leads to the disruption of the supramolecular vesicles. [ABSTRACT FROM AUTHOR]

Mechanisms underlying elevated blood pressure in dialysis patients are complex as a variety of non-traditional factors are involved. We sought to explore the association of circulating betaine, a compound widely distributed in food, with blood pressure in dialysis patients. We used baseline data of an ongoing cohort study involving patients on hemodialysis. Plasma betaine was measured by high performance liquid chromatography in 327 subjects. Blood pressure level was determined by intradialytic ambulatory blood pressure monitoring. The mean age of the patients was 52.6 ± 11.9 years, and 58.4% were male. Average interdialytic ambulatory systolic and diastolic blood pressure were 138.4 ± 22.7 mm Hg and 84.4 ± 12.5 mm Hg, respectively. Mean plasma betaine level was 37.6 μmol/L. Multiple linear regression analysis revealed significant associations of betaine with both systolic blood pressure (β = -3.66, P = .003) and diastolic blood pressure (β = -2.00, P = .004). The associations persisted even after extensive adjustment for cardiovascular covariates. Subgroup analysis revealed that the association between betaine and blood pressure was mainly limited to female patients. Our data suggest that alteration of circulating betaine possibly contributes to blood pressure regulation in these patients. [ABSTRACT FROM AUTHOR]

A series of high energy density compounds (HEDCs) based on N-nitrourea were designed and their theoretical performances were calculated using the Gaussian programs. The predicted values of the energy density of these compounds are in the range 1.848-1.93 g cm−3, and their calculated VODs are in the range 6700-8305 m s−1. Tetranitrodiglycoluril (TNDGU) ( 1) and tetranitrotriglycoluril (TNTGU) ( 2) were synthesized and characterized by NMR (1H, 13C) and IR spectroscopy as well as elemental analyses. The structure of the aminolysis product ( 7) of TNDGU was further confirmed by single-crystal X-ray diffraction, which indicated that the structure belongs to P21/ c space group in the monoclinic system. [ABSTRACT FROM AUTHOR]

Ethylene responsive factors (ERFs) are plant-specific transcription factors that are involved in a variety of biological processes. We previously demonstrated that an ERF gene from Tamarix hispida, ThERF1, encodes a protein binding to GCC-box and DRE motifs and negatively modulates abiotic stress tolerance. In the present study, microarray analysis was performed to study the genes regulated by ThERF1 on a genomic scale. There were 154 and 307 genes (respectively representing 134 and 260 unique genes) significantly up- and downregulated by ThERF1 under salt stress conditions, respectively. A novel motif, named TTG, was identified to be recognized by ThERF1, which commonly presents in the promoters of ThERF1-targeted genes. The TTG motif is also bound by other ERFs of a different subfamily from T. hispida and Arabidopsis, indicating that it is commonly recognized by ERF proteins. The binding affinities of ERFs to the TTG motif are significantly induced by salt stress. The TTG motif is more enriched than the GCC-box and DRE motifs in the promoters of ThERF1-targeted genes. Taken together, these studies suggested that the TTG motif plays an important role in the gene expression regulated by ERFs in response to salt stress. [ABSTRACT FROM AUTHOR]

Although ambulatory blood pressure (ABP) monitoring (ABPM) is often considered to have an advantage over dialysis unit blood pressure (BP) in dialysis patients, the exact relationship between these two measurements of BP has not been well determined. In a cohort of 90 Chinese dialysis patients, agreement between dialysis unit BP (predialysis and postdialysis BP) and interdialytic ABP was evaluated using Bland-Altman plots and Lin's concordance correlation coefficient for quantitative analysis, and inter-rater agreement (κ) for qualitative analysis. Limits of agreement between dialysis unit BP and ABP were wide (predialysis systolic BP: -33.5 to 20.9 mm Hg; predialysis diastolic BP: -22.2 to 11.9 mm Hg; postdialysis systolic BP: -25.4 to 26.5 mm Hg; postdialysis diastolic BP: -18.4 to 12.3 mm Hg). Lin's concordance correlation coefficient exhibited a poor agreement with concordance correlation coefficients of 0.75, 0.81, 0.64, and 0.75 for predialysis systolic BP, postdialysis systolic BP, predialysis diastolic BP, and postdialysis diastolic BP, respectively. When BP level was classified into quartiles, an increasing trend for incorrect classification rate was observed with deleterious hypertension, with the highest value in grade 3 hypertension (100% and 75.0% for predialysis and postdialysis BP, respectively). Therefore, these data suggest that agreement between dialysis unit BP and interdialytic ABP is poor in Chinese dialysis patients, and the bias for patients with higher degree of hypertension is more prominent. [ABSTRACT FROM AUTHOR]

Somatic sequencing of cancers has produced new insight into tumorigenesis, tumor heterogeneity, and disease progression, but the vast majority of genetic events identified are of indeterminate clinical significance. Here, we describe a NextGen sequencing approach to fully analyzing 248 genes, including all those of known clinical significance in melanoma. This strategy features solution capture of DNA followed by multiplexed, highthroughput sequencing and was evaluated in 31 melanoma cell lines and 18 tumor tissues from patients with metastatic melanoma. Mutations in melanoma cell lines correlated with their sensitivity to corresponding small molecule inhibitors, confirming, for example, lapatinib sensitivity in ERBB4 mutant lines and identifying a novel activating mutation of BRAF. The latter event would not have been identified by clinical sequencing and was associated with responsiveness to a BRAF kinase inhibitor. This approach identified focal copy number changes of PTEN not found by standard methods, such as comparative genomic hybridization (CGH). Actionable mutations were found in 89% of the tumor tissues analyzed, 56% of which would not be identified by standardof- care approaches. This work shows that targeted sequencing is an attractive approach for clinical use in melanoma. [ABSTRACT FROM AUTHOR]

The two most commonly used strategies to evaluate dialysis patients' blood pressure ( BP) level are 44-hour and 24-hour ambulatory blood pressure monitoring ( ABPM). The objective of this study was to find an appropriate 24-hour period that correlated well with the 44-hour BP level and determine the differences between these strategies. In a group of 51 dialysis patients, the authors performed 44-hour ABPM and extracted data for a fixed 24-hour ABPM. The fixed 24-hour ABPM started at 6 am on the nondialysis day. A strong correlation was found between all parameters of 44-hour and the fixed 24-hour ABPM, with paired sample t test showing only small magnitude changes in a few parameters. Both 24-hour ABPM and 44-hour ABPM were superior to clinic BP in predicting left ventricular mass index ( LVMI) by multiple regression analysis. It was found that 44-hour ambulatory arterial stiffness index ( AASI), but not 24-hour AASI, had a positive association with LVMI ( r=0.328, P=.021). However, after adjustment for 44 -hour systolic blood pressure, this association disappeared. Fixed 24 -hour ABPM is a good surrogate of 44-hour ABPM to some extent, while 44-hour ABPM can provide more accurate and detailed information. [ABSTRACT FROM AUTHOR]

Summary: In this paper, a chaos‐based optimization algorithm is employed for medical images contrast enhancement. Here, a weighted combined framework is suggested as the cost function for the contrast enhancement. The method utilizes the advantages of Gamma correction, histogram equalization, and edge information for decreasing the original image features losses. For more enhancements, a piecewise version of Gamma correction is also utilized to decrease the unnatural artifacts in the output image. A combined cost function is employed based on the three aforementioned features and the proposed chaos world cup optimization algorithm is used for maximizing the fitness function. The simulation results have been compared with five state‐of‐the‐art methods for presenting the method efficiency. To do this, contrast, homogeneity, weighted average peak SNR, a measure of enhancement, and contrast noise ratio are employed. The results also applied to two standard medical imaging datasets and compared with the other methods. Final results denoted that the presented multiobjective optimization algorithm improves the quality of the image contrast and can illustrate more details and information toward the other compared methods. [ABSTRACT FROM AUTHOR]

Mechanoluminescence (ML) is a fascinating phenomenon with diverse applications in pressure sensing, damage detection, and stress distribution visualization. However, most ML materials exhibit instantaneous photon emission that requires real‐time recording with a photodetector, and thereby circumscribing their applicability predominantly to real‐time stress‐sensing scenarios. In this work, a novel method is introduced for non‐real‐time stress sensing utilizing Li0.1Na0.9NbO3:Pr3+ phosphor, which allows for the retrieval of pressure location and intensity even 20 days after the event. The influence of heat and pressure on the trap depth distribution is analyzed using thermoluminescence (TL) and ML measurements, and it is proved that both heat and pressure release the captured electrons in the same traps. Leveraging the intricate competition between mechanical and thermal detrapping processes, stress information can be accessed through TL imaging. Furthermore, an algorithm is proposed based on this phenomenon to authenticate the stress information. This research not only advances the fundamental understanding of ML phenomena but also introduces a novel approach for applications such as mechano‐history indicators, security papers, and advanced data storage systems. [ABSTRACT FROM AUTHOR]

The article presents information on the phenomena of senescence escape in melanoma cells. It reflects on the oncogenic activation of B-RAF which results in reduced level of PI3K signaling and increased level of p16INK4a expression. It shows that the loss of either PTEN or p16INK4a or both results in senescence-escape and melanoma progression, and also informs about the oncogene-induced senescence (OIS) that results from the expression of mutant either B-RAF or N-RAS genes.