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To improve accuracy of the MobileNet network, a new lightweight deep neural network is designed based on the MobileNetV2 network. Firstly, it modifies the network depth of MobileNetV2 to balance the image resolution, network width and depth to keep the gradient stable, which reduces the generation of gradient vanishing or gradient exploding. Secondly, it proposes an improved Bottleneck module by introducing channel attention mechanism. It assigns different weights for different channels according to the degree of relevance between the object features and channels. Therefore, the network can extract more effective features from a complex background. In the end, a new usage strategy of the improved Bottleneck is proposed. It uses the improved Bottleneck module in the second, fourth and fifth stages of MobileNetV2, and uses the original Bottleneck module in other states. Compared with MobileNetV2, MobileNetV3, ShuffleNetV2, GhostNet and HBONetmethods, the proposed method has the highest classification accuracy on the ImageNet-1K dataset, CIFAR-10 and CIFAR-100. Compared with YOLOV4-Lite methods based on these lightweight network networks, YOLOV4-Lite based on our proposed network also has the highest detection accuracy on the PASCAL VOC07+12 dataset. [ABSTRACT FROM AUTHOR]

Although wheat (Triticum aestivum L.) pericarp starch granule (PSG) has been well-studied, our knowledge of its features and mechanism of accumulation and degradation during pericarp growth is poor. In the present study, developing wheat caryopses were collected and starch granules were extracted from their pericarp to investigate the morphological and structural characteristics of PSGs using microscopy, X-ray diffraction and Fourier transform infrared spectroscopy techniques. Relative gene expression levels of ADP-glucose pyrophosphorylase (APGase), granule-bound starch synthase II (GBSS II), and α-amylase (AMY) were quantified by quantitative real-time polymerase chain reaction. PSGs presented as single or multiple starch granules and were synthesized both in the amyloplast and chloroplast in the pericarp. PSG degradation occurred in the mesocarp, beginning at 6 days after anthesis. Amylose contents in PSGs were lower and relative degrees of crystallinity were higher at later stages of development than at earlier stages. Short-range ordered structures in the external regions of PSGs showed no differences in the developing pericarp. When hydrolyzed by α-amylase, PSGs at various developmental stages showed high degrees of enzymolysis. Expression levels of AGPase, GBSS II, and AMY were closely related to starch synthesis and degradation. These results help elucidate the mechanisms of accumulation and degradation as well as the functions of PSG during wheat caryopsis development. [ABSTRACT FROM AUTHOR]

Retinal ischemia is a common feature associated with several ocular diseases, including diabetic retinopathy. In this study, we investigated the effect of a retinal ischemia and reperfusion (I/R) injury on protein levels via a quantitative shotgun strategy using stable isotope dimethyl labeling combined with LC-MS/MS analysis. Based on the relative quantitation data of 1088 proteins, 234 proteins showed a greater than 1.5-fold change following I/R injury, 194 of which were up-regulated and 40 were down-regulated. Gene ontology analysis revealed that after I/R injury, there was an increase in the metabolic-process related proteins but a decline in cell communication, system process and transport-related proteins. A ribosome protein network and a secreted protein network consisting of many protease inhibitors were identified among the up-regulated proteins, despite a suppression of the mammalian target of rapamycin (mTOR) pathway following the I/R injury. A synaptic-related protein network was found to be significantly down-regulated, implicating a functional reduction of neurons following a retinal I/R injury. Our results provide new systems-biology clues for the study of retinal ischemia. [ABSTRACT FROM AUTHOR]

Background: PTPRD, encoding protein tyrosine phosphatases receptor type D, is located at chromosome 9p23–24.1, a loci frequently lost in many types of tumors. Recently, PTPRD has been proposed to function as a tumor suppressor gene. The current study aimed to investigate PTPRD expression and its prognostic significance in primary gastric adenocarcinoma. Methods and Results: Quantitative real time reverse transcription PCR (qRT-PCR) and western blotting were used to examine PTPRD expression in paired gastric tumourous and paracancerous tissues. Compared with the matched normal gastric mucosa tissues, both the mRNA (P = 0.0138) and protein (P = 0.0093) expression of PTPRD in fresh surgical specimens were significantly reduced. Clinicopathological and prognostic roles of PTPRD in gastric adenocarcinoma were investigated using immunohistochemistry with 513 paraffin-embedded gastric adenocarcinoma tissue blocks. Statistical analysis revealed that reduced PTPRD expression was significantly associated with T stage (P = 0.004), TNM stage (P<0.001) and tumor size (P = 0.003). Furthermore, Kaplan-Meier survival analysis revealed that low expression of PTPRD significantly correlated with poor survival of gastric cancer patients (P<0.001). Cox regression analysis confirmed PTPRD expression as independent predictor of the overall survival of gastric cancer patients. The MTT assay determined the effects of PTPRD on cell proliferation of MGC803 and GES1 cell lines. Restoring PTPRD expression in MGC803 cells significantly inhibited their growth rate. Silencing PTPRD expression by siRNA treatment in GES1 significantly enhanced cell proliferation compared with mock siRNA treatment. Methylation analysis of PTPRD promoter CpG island in 3 primary GC samples showed one case with partial methylation. Conclusions: These results indicated that PTPRD is a candidate tumour suppressor in gastric cancer. Thus, PTPRD may play an important role in gastric tumorigenesis and serve as a valuable prognostic marker of gastric adenocarcinoma. [ABSTRACT FROM AUTHOR]