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Accurate brain tumor segmentation using multi-sequence magnetic resonance (MR) imaging plays a pivotal role in clinical practice and research settings. Despite their prevalence, deep learning-based segmentation methods, which usually use multiple MR sequences as input, still have limited performance, partly due to their insufficient ability to image representation. In this paper, we propose a brain tumor segmentation (BraTSeg) model, which uses cross-sequence MR image generation as a self-supervision tool to improve the segmentation accuracy. This model is an ensemble of three image segmentation and generation (ImgSG) models, which are designed for simultaneous segmentation of brain tumors and generation of T1, T2, and Flair sequences, respectively. We evaluated the proposed BraTSeg model on the BraTS 2019 dataset and achieved an average Dice similarity coefficient (DSC) of 81.93%, 87.80%, and 83.44% in the segmentation of enhancing tumor, whole tumor, and tumor score on the testing set, respectively. Our results suggest that using cross-sequence MR image generation is an effective self-supervision method that can improve the accuracy of brain tumor segmentation and the proposed BraTSeg model can produce satisfactory segmentation of brain tumors and intra-tumor structures.

Staphylococcus aureus is a common foodborne pathogenic microorganism. A modified propidium monoazide (PMAxx) dye combined with recombinase aided amplification (RAA) was proposed for the rapid and real-time detection of viable S. aureus. PMAxx, a kind of nucleic acid dye is used to distinguish viable bacteria from dead bacteria. Additionally, RAA technique has the advantage of a short detection time (20 min) and uniform temperature (39 °C), which is of great significance for the efficient detection of S. aureus. The S. aureus nuc gene was used as primer and probe in a microplate assay. The effect of PMAxx treatment exhibited permeation of the dead cell membranes that was observed under confocal laser scanning microscope (CLSM). After the enrichment of viable target bacteria ranging from 5.4 × 101 to 5.4 × 103 CFU/mL, the LOD for viable S. aureus was 102 CFU/mL under 3 h enrichment and 101 CFU/mL under 6 h enrichment in artificially contaminated milk, respectively. In the presence of nontarget bacteria at 106 CFU/mL, the system could detect 107 CFU/mL S. aureus in milk sample. The proposed PMAxx-RAA assay exhibited potential for the accurate and rapid viable S. aureus detection in milk.

We analyzed the scats of Amur tigers and Amur leopards, and examined their annual and seasonal food habits in Northeast China to comprehend their coexistence. Wild boar had the highest annual and seasonal consumption frequencies by the tigers, while both roe deer and sika deer were mostly preyed by the leopards annually. The three species appeared to be the key preys in terms of high proportion of consumed biomass by the two felids. Our data also revealed numerous mid-sized carnivores and small mammals included in the two felids’ food list. We used the relative abundance and biomass density estimation in prey density estimation to calculate the prey preferences of tigers and leopards, and both methods confirmed that Amur tigers strongly preferred wild boar. However, preference estimations of Amur leopards were not consistant, or even opposite to one another from the two methods. The results of the study suggested that prey preference of predators is largely determined by body size of the prey species. Variation in diet composition of the two felids suggests that resource partitioning may contribute to their coexistence.

Tannic acid, propyl gallate, methyl gallate, and gallic acid were tested for their inhibitory effects on selected aquatic microorganisms by the well assay technique. Tannic acid, propyl gallate, and methyl gallate in deionized water inhibited the growth of Aeromonas hydrophila, A. sobria, Edwardsiella iclaluri, E. tarda, Pseudomonas fluorescens, and Escherichia coli, but gallic acid did not. When 500-μg/mL concentrations of these four compounds were tested in sterilized fish pond water at pH 7.0 and with a low bacterial inoculum of 103–104 colony-forming units (CFU) per milliliter, they inhibited the growth of P. fluorescens and (except for tannic acid) E. coli. Pseudomonas fluorescens inoculated at 103–104 CFU/mL in pond water was inhibited by methyl gallate, propyl gallate, and tannic acid concentrations as low as 50 μg/mL, but a gallic acid contration of 100 μg/mL was required for inhibition. Escherichia coli was inhibited by methyl gallate and propyl gallate at 250 μg/mL and by gallic acid at...

Genetic alterations serve as beacons for the involvement of specific pathways in tumorigenesis. It was previously shown that 5% of prostate tumors harbor CTNNB1 mutations, suggesting that this tumor type may involve a deregulated APC/CTNNB1 pathway. To explore this possibility further, we searched for mutations in genes implicated in this pathway in 22 samples that included cell lines, xenografts, and primary tumors. We identified seven alterations: two in CTNNB1, three in APC, and two in hTRCP1 (also known as BTRC) which controls the degradation of CTNNB1. Alterations in the CTNNB1 regulatory domain, APC, and hTRCP1 were mutually exclusive, consistent with their equivalent effects on CTNNB1 stability. These results suggest that CTNNB1 signaling plays a critical role in the development of a significant fraction of prostate cancers. Moreover, they provide the first evidence that hTRCP1 plays a role in human neoplasia. © 2002 Wiley-Liss, Inc.