In the past few years, convolutional neural networks (CNNs) have achieved milestones in medical image analysis. Especially, the deep neural networks based on U-shaped architecture and skip-connections have been widely applied in a variety of medical image tasks. However, although CNN has achieved excellent performance, it cannot learn global and long-range semantic information interaction well due to the locality of convolution operation. In this paper, we propose Swin-Unet, which is a Unet-like pure Transformer for medical image segmentation. The tokenized image patches are fed into the Transformer-based Ushaped Encoder-Decoder architecture with skip-connections for localglobal semantic feature learning. Specifically, we use hierarchical Swin Transformer with shifted windows as the encoder to extract context features. And a symmetric Swin Transformer-based decoder with patch expanding layer is designed to perform the up-sampling operation to restore the spatial resolution of the feature maps. Under the direct downsampling and up-sampling of the inputs and outputs by 4×, experiments on multi-organ and cardiac segmentation tasks demonstrate that the pure Transformer-based U-shaped Encoder-Decoder network outperforms those methods with full-convolution or the combination of transformer and convolution. The codes and trained models will be publicly available at https://github.com/HuCaoFighting/Swin-Unet.

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In this study, localized surface plasmon resonance mediated by aluminium nanoparticles (Al NPs) was employed to enhance the ultraviolet (UV) response of ZnO nanorod array (NRA) photodetectors grown vertically on a Quartz substrate using a simple vapor transport method. The responsivity of the ZnO NRA photodetector decorated with Al NPs was enhanced from 0.12 to 1.59 A W(-1) and the sensitivity and response rate have been improved greatly compared with those of the bare one. The measurement results in the transmittance spectra and time-resolved photoluminescence spectra suggest that the improved photoresponse and the enhanced spontaneous emission of the ZnO NRA photodetector with Al NP decoration are both attributed to resonant coupling between the excitons in ZnO and the localized surface plasmons (LSPs) in the Al NPs. Our results demonstrated that the plasmon-enhanced ZnO NRA photodetector has a great potential for application in building sensors with a fast response and reset time, high sensitivity, and good signal-to-noise ratio for photoelectric sensing.

Hypoxia-induced inflammation and excessive proliferation of pulmonary artery smooth muscle cells (PASMCs) play important roles in the pathological process of hypoxic pulmonary hypertension (HPH). Melatonin possesses anti-inflammatory and antiproliferative properties. However, the effect of melatonin on HPH remains unclear. In this study, adult Sprague-Dawley rats were exposed to intermittent chronic hypoxia for 4 wk to mimic a severe HPH condition. Hemodynamic and pulmonary pathomorphology data showed that chronic hypoxia significantly increased right ventricular systolic pressures (RVSP), weight of the right ventricle/left ventricle plus septum (RV/LV+S) ratio, and median width of pulmonary arterioles. Melatonin attenuated the elevation of RVSP, RV/LV+S, and mitigated the pulmonary vascular structure remodeling. Melatonin also suppressed the hypoxia-induced high expression of proliferating cell nuclear antigen (PCNA), hypoxia-inducible factor-1α (HIF-1α), and nuclear factor-κB (NF-κB). In vitro, melatonin concentration-dependently inhibited the proliferation of PASMCs and the levels of phosphorylation of Akt and extracellular signal-regulated kinases1/2 (ERK1/2) caused by hypoxia. These results suggested that melatonin might potentially prevent HPH via anti-inflammatory and antiproliferative mechanisms.

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MicroRNAs (miRNAs) have been identified as major post-transcriptional regulators of the initiation and progression of human cancers, including breast cancer. However, the detail role of miR-451 has not been fully elucidated in breast cancer. In this study, we aimed to investigate the biological role and molecular mechanisms of miR-451 in drug resistance in breast cancer cell lines and in xenograft model. We show that miR-451 is decreased in human breast cancer specimens and in paclitaxel-resistant (PR) cells. Ectopic expression of miR-451 could inhibit the cell migration and invasion, promoted apoptosis, induced cell-cycle arrest Furthermore, tyrosine3-monooxygenase/tryptophan5-monooxygenase activation protein zeta (YWHAZ) was identified as a direct target of miR-451. Remarkably, the expression of YWHAZ is inversely correlated with the level of miR-451 in human breast cancer samples. Co-treatment with miR-451 mimics and YWHAZ-siRNA significantly enhanced YWHAZ knockdown in both SKBR3/PR and MCF-7/PR cells Moreover, miR-451 markedly inhibited expression of β-catenin via YWHAZ and subsequently inhibited downstream gene cyclin D1, c-Myc expression. The results of xenograft model in vivo showed that intratumor injection of miR-451 agomir induced a tumor-suppressive effect in SKBR3/PR drug-resistant xenograft model. Taken together, our findings suggested that miR-451 might be considered as important and potential target in paclitaxel-resistant breast cancer treatment.

Artemisinin, a sesquiterpene lactone endoperoxide derived from Artemisia annua L., is the most effective antimalarial drug. In an effort to increase the artemisinin production, abscisic acid (ABA) with different concentrations (1, 10 and 100 µM) was tested by treating A. annua plants. As a result, the artemisinin content in ABA-treated plants was significantly increased. Especially, artemisinin content in plants treated by 10 µM ABA was 65% higher than that in the control plants, up to an average of 1.84% dry weight. Gene expression analysis showed that in both the ABA-treated plants and cell suspension cultures, HMGR, FPS, CYP71AV1 and CPR, the important genes in the artemisinin biosynthetic pathway, were significantly induced. While only a slight increase of ADS expression was observed in ABA-treated plants, no expression of ADS was detected in cell suspension cultures. This study suggests that there is probably a crosstalk between the ABA signaling pathway and artemisinin biosynthetic pathway and that CYP71AV1, which was induced most significantly, may play a key regulatory role in the artemisinin biosynthetic pathway.

Accurate segmentation of organ at risk (OAR) play a critical role in the treatment planning of image guided radiation treatment of head and neck cancer. This segmentation task is challenging for both human and automatic algorithms because of the relatively large number of OARs to be segmented, the large variability of the size and morphology across different OARs, and the low contrast of between some OARs and the background. In this paper, we proposed a two-stage segmentation framework based on 3D U-Net. In this framework, the segmentation of each OAR is decomposed into two sub-tasks: locating a bounding box of the OAR and segment it from a small volume within the bounding box, and each sub-tasks is fulfilled by a dedicated 3D U-Net. The decomposition makes each of the two sub-tasks much easier, so that they can be better completed. We evaluated the proposed method and compared it to state-ofthe-art methods by using the MICCAI 2015 Challenge dataset. In terms of the boundary-based metric 95HD, the proposed method ranked first in eight of all nine OARs and ranked second in the other OAR. In terms of the area-based metric DSC, the proposed method ranked first in six of the nine OARs and ranked second in the other three OARs with small difference with the first one.