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Polystyrene polymers cause severe toxicity to aquatic animals. However, the process and mechanisms of innate immunity of invertebrates living at the bottom of the food chain to these pollutants remain unclear. In this study, the blood system responses of zooplankton Artemia were assessed through in vivo and in vitro exposure to amino-modified polystyrene nanoplastics (PS-NH 2 NPs). The results indicated that the LC 50 values of PS-NH 2 NPs were 1.09 μg·mL−1 over 48 h and 0.42 μg·mL−1 over 7 d. Based on the five hemocyte subpopulations identified in Artemia , in vitro exposure assays revealed that phagocytosis was performed by plasmocytes and granulocytes with phagocytic rate of 22.64 %. TEM analysis further showed that PS-NH 2 NPs caused cytoplasm vacuolization, swollen mitochondria, and lipid processing disorder. Gene expression pattern results demonstrated that Spatzle, Tollip, Hsp70, Hsp90, Casp8, API5and Pxn were significantly upregulated upon acute and chronic exposure (p < 0.05), while chronic exposure could induce significantly upregulation of ProPO (p < 0.05). Moreover, PS-NH 2 NPs exposure remarkably varied the hemolymph microbiota and hemogram, particularly by increasing the proportion of adipohemocytes and phagocytes (p < 0.05). Our findings suggest that PS-NH 2 NPs induce different responses in Artemia hemocyte, as primarily reflected by phagocytic processes, expression of immune and apoptosis relating genes, cell fates, hemogram and hemolymph microbiota variations. These findings support the possibility of using Artemia hemocytes as bioindicator to estimate nanoplastics pollution, thus contributing to hematological toxicity research in response to nanoplastics. [Display omitted] • We identified hemocyte populations and revealed hemogram variation of Artemia. • It is worth paying attention to the immunocyto-toxicity caused by PS-NH 2 NPs. • Significant changes of hemolymph microbiota occurred after chronic exposure. • Artemia hemocyte is a potential indicator to evaluate the toxicity of nanoplastics. [ABSTRACT FROM AUTHOR]

Various known and unknown viral diseases can threaten crustacean aquaculture. To develop prophylactic and therapeutic strategies against viruses, crustacean cell lines are urgently needed for immunology and virology studies. However, there are currently no permanent crustacean cell lines available. In this study, we developed a new method for preparing crayfish plasma (CP) and found that CP enhanced the proliferative capacity of haematopoietic tissue (hpt) cells from Cherax quadricarinatus by an EdU (5-ethynyl-2′-deoxyuridine) assay. The optimal CP concentration for hpt cell culture and the optimal subculture method are discussed. To achieve efficient expression of a foreign gene in hpt cells cultured in vitro , different transfection methods and vectors were analysed. We found that Lipofectamine 2000 could be used to efficiently transfect a foreign vector into hpt cells and exhibited a lower level of cytotoxicity than the other methods tested, and transfection of pEGFP-N1/w249 and pDHsp70-EGFP-FLAG resulted in high EGFP expression. By transmission electron microscopy (TEM) and virus copy number analysis, we found that white spot syndrome virus (WSSV) could infect hpt cells and multiply efficiently. Our results implied that the crayfish hpt cell culture system we improved could be used as a replacement for immortal crustacean cell lines in viral infection studies. Our findings provide a solid foundation for future immortalization and gene function studies in crustacean cells. [ABSTRACT FROM AUTHOR]

Neurodegenerative diseases are neurological diseases that are characterized by neuronal degeneration and apoptosis; they threaten populations around the world and place a great burden on the social economy. Unfortunately, the drugs currently used to treat neurodegenerative diseases have obvious side effects, making them much less effective. Therefore, discovery of new safe and effective drugs is urgently needed. Zanthoxylum bungeanum Maxim. (ZBM) has a long medicinal history in China and can also be used as food. ZBM contains many types of chemical components, of which amides are the most abundant. In preparing this review, we searched and integrated the relevant literature in PubMed, Web of Science, Elesvier, Wliey and Springer using the keywords "ZBM", "amide", "physicochemical properties", and "neurodegenerative diseases". It was found that the amides that are present in ZBM (AZB), although structurally unstable, are the likely material basis for an irritating sensation in the mout,. In addition, AZB can play a therapeutic role in Alzheimer's disease, Parkinson's and depression by exerting antioxidant and anti-inflammatory effects. The main targets of AZB are the TRPV1, TRPA1 and PI3K/AKT signalling pathways. This review will discuss the physical and chemical properties of AZB and its use in the treatment of neurodegenerative diseases to provide a reference for the development of ZBM for use in the treatment of neurodegenerative diseases. [ABSTRACT FROM AUTHOR]

The hemocytes of the red claw crayfish Cherax quadricarinatus are classified by morphologic observation into the following types: hyalinocytes (H), semi-granulocytes (SG) and granulocytes (G). Density gradient centrifugation with Percoll was developed to separate these three subpopulations of hemocytes. Beads, Escherichia coli , and FITC labeling WSSV were used to investigate the characteristics of granulocytes by using scanning electron microscope, transmission electron microscope, and laser scan confocal microscope. Results showed that granulocytes could phagocytose beads and E. coli by endocytic pathways. WSSV could rely on caveolae-mediated endocytosis to mainly enter into granulocytes. These results could elucidate the mechanism of the innate immunity function of granulocytes, and it also showed the mechanism by which WSSV invaded granulocytes in the red claw crayfish. [ABSTRACT FROM AUTHOR]

Abstract: The left and right-turning scheme of weldments was adopted to detect small porosities in laser weldments with complex structures. Detection images were obtained in this study. An algorithm that determines the optimal structure elements for morphology simulation was provided to achieve fidelity segmentation of small porosities. Mathematical models for the defect depth and deviation of bulk porosities were established based on the geometric features of laser weldments. Thus, the features of spatial distribution of small porosities were determined. To improve detection efficiency, the automatic extraction of spatial position data for bulk porosities was divided into two parts: automatic extraction of projection distance, which is important for the determination of weld porosity depth and deviation, and automatic extraction of porosity size. The porosity distribution in the longitudinal direction was obtained by automatic searching, and the features of the spatial distribution of weld porosities were procured. A 3D model of laser weldments was established to visualize the spatial distribution of porosities. Extracted data were inputted to the model, and the spatial positions of bulk porosities were visualized. [Copyright &y& Elsevier]

Abstract: Aiming at the disadvantages of the present electric parameters detection of power harmonics, a power system harmonic detection technique based on sliding-windows iterative of discrete Fourier transform (SWIDFT) and wavelet transform (WT) are proposed in this paper. Using SWIDFT to detect the fundament components and the total harmonic components and using WT to extract and separate the fundamental harmonic and the high order harmonic contents from the total harmonic components. Simulation results obtained by this algorithm reveal that the proposed method can detect harmonic signal precisely. Therefore, it provides an effective means for power system harmonic analysis and detection. [Copyright &y& Elsevier]

Abstract: In order to study the segmentation and quantitative problem of small defects in precision weldments with complex structure, an automated image processing system was setup based on the Visual Basic 6.0 development environment. The weld zones were extracted by adopting the method of twice automatic threshold, and the small defects were segmented successfully by using sharpen, smoothing processing and background subtraction in the extracted weld zones. To determine the spatial distribution features of small defects, calculation formula of defects depth and deviation were deduced individually, and the projection distance of small defects can be extracted automatically also. The image processing system can achieve the goal of small defects segmentation and automatic extraction of projection distance. The depth and deviation of small defects can be obtained through the above deduced formula, and the longitudinal distribution of small defects can be obtained from the detection image, then the spatial distribution features of small defects can be determined. [Copyright &y& Elsevier]