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PURPOSE A locally segmented parallel imaging reconstruction method is proposed that efficiently utilizes sensitivity distribution of multichannel receiver coil. selleck compound THEORY AND METHODS A method of locally segmenting a MR signal is introduced to maximize the differences in sensitivity between receiver channels. A 1D Fourier transformation of the undersampled k-space data is performed along the readout direction, which generates a hybrid 2D space. The hybrid space is partitioned into localized segments along the readout direction. In every localized segment, kernels representing relation between adjacent signals are estimated from autocalibration signals, and data at unsampled points are estimated using the kernels. Then, the images are reconstructed from full k-space data that consists of the sampled data and the estimated data at unsampled points. RESULTS In a computer simulation and in vivo experiments, the locally segmented reconstruction method produced fewer residual artifacts compared to the conventional parallel imaging reconstruction methods with the same kernel geometry. The performance gain of the proposed method comes from maximizing encoding capability of receiver channels, thus resulting in the accurately estimated kernel weights that reflect the relation between adjacent signals. CONCLUSION The proposed spatial segmentation method maximally utilizes differences in the sensitivity of receiver channels to reconstruct images with reduced artifacts. © 2020 International Society for Magnetic Resonance in Medicine.In ecotoxicology and aquatic ecology, we often ignore responses of individuals and focus on average responses. Yet, both terrestrial and aquatic animals display consistent behavioural differences between individuals. The distribution of behavioural differences within a population contains vital information for predicting population responses to novel environmental challenges. Currently, individual data for behavioural and physiological traits of small marine invertebrates are few, partly because such variation is lost within published group means and assumed normality. We tested the combined effects of an inorganic contaminant (copper) and a biological stressor (i.e. chemical cues of a fish predator) on activity in a marine copepod. While direct stress effects were weak, individuals behaved consistently different, yet depending on context. Individual differences in behaviour were only expressed under the influence of kairomones, but not by copper exposure alone. This indicates that copepods express repeatable and context dependent behaviour. We also demonstrate how large variation in behavioural data can hide consistent differences between individuals. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.This study investigated if EX-527 has an anti-tumour effect in SKOV-3 and OVCAR-3 ovarian cancer (OC) cell lines and if this effect involves the SIRT1/NF-κB axis. Cells were cultured in the presence or absence of EX-527, a selective SIRT-1 inhibitor. Exendin-4 significantly induced cell death in both cell lines and inhibited cell migration and invasion. Also, it decreased protein levels of Bcl-2, MMP-9, and ICAM-1 and increased those of Bax, cyclin D1 and cleaved caspase-3. Mechanistically, Exendin-4 increased the activity and nuclear accumulation of SIRT1 and decreased nuclear levels of NF-κB p65; acetylated levels of NF-κB p65, and cytoplasmic levels of p-IKKα and p-IκBα. EX-527 partially ameliorated the effect of Exendin-4 on cell death, migration, and invasion, as well as on the expression of Bcl-2, MMP-9, Bax, cleaved caspase-3 and ICAM-1. In addition, EX-527 did not affect the levels of nuclear p65 and p-p65 (Ser536); p-IκBα (Ser32) and p-IKKαβ. In conclusion, Exendin-4 can suppress OC by inhibiting NF-kB through SIRT1 dependent and independent mechanisms. © 2020 John Wiley & Sons Australia, Ltd.Carboplatin (CBP) is a widely used targeted anticancer therapeutic drug, however, multi-drug resistance induced by the accumulation of CBP eventually causes diseases progression. The anti-malarial drug artesunate (ART) also exerts anti-cancer effects in various cancers; however, the combined effect of ART and CBP on non-small cell lung cancer (NSCLC) remains unclear. In the present study, the NSCLC cell line A549 was pretreated with various concentrations of CBP, ART and gemcitabine (GEM). 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays were conducted to detect cell viability. Cell apoptosis was evaluated by both flow cytometry and TUNEL apoptotic assay. The expression profiles of cell cycle-related proteins and apoptotic proteins were determined by western blot. Cell clone numbers were visualized using crystal violet staining. Here, we found that both CBP and ART suppressed cell viability, and promoted cell apoptosis, and the combined application of ART and CBP at a lower concentration exhibited synergistic effects. Specifically, the combination of ART and CBP at a lower concentration suppressed cell clone numbers, promoted cell cycle arrest at the G2 /M phase, and induced the expression of the cell cycle and apoptosis related proteins BAX, p21, p53, and Caspae-3, while decreasing Bcl-2 and CyclinB1 expression. Based on these results, we concluded that combined application of ART and CBP exerts synergistic anti-tumor effects on NSCLC by enhancing cell apoptosis in a mitochondria-dependent manner. This article is protected by copyright. All rights reserved.PURPOSE Chemical exchange saturation transfer (CEST) is an MRI technique sensitive to the presence of low-concentration solute protons exchanging with water. However, magnetization transfer (MT) effects also arise when large semisolid molecules interact with water, which biases CEST parameter estimates if quantitative models do not account for macromolecular effects. This study establishes under what conditions this bias is significant and demonstrates how using an appropriate model provides more accurate quantitative CEST measurements. METHODS CEST and MT data were acquired in phantoms containing bovine serum albumin and agarose. Several quantitative CEST and MT models were used with the phantom data to demonstrate how underfitting can influence estimates of the CEST effect. CEST and MT data were acquired in healthy volunteers, and a two-pool model was fit in vivo and in vitro, whereas removing increasing amounts of CEST data to show biases in the CEST analysis also corrupts MT parameter estimates. RESULTS When all significant CEST/MT effects were included, the derived parameter estimates for each CEST/MT pool significantly correlated (P  less then  .

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