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Simple Summary: As a filter-feeding and sessile invertebrate living in estuaries and intertidal areas, Crassostrea gigas must cope with and adapt to a dynamic and changeable environment. Vibrio alginolyticus is a Gram-negative bacterium that is widespread in oceans and estuaries, and is one of the main Vibrio species that cause oyster disease. In this study, we used transcriptome sequencing to help us better understand how the giant oyster adapts to pathogen-rich environments. By focusing on the gills, which play a crucial role in the immune response, we aimed to shed light on the molecular processes underlying the interaction between the oyster and the pathogen. Over the years, oysters have faced recurring mass mortality issues during the summer breeding season, with Vibrio infection emerging as a significant contributing factor. Tubules of gill filaments were confirmed to be in the hematopoietic position in Crassostrea gigas, which produce hemocytes with immune defense capabilities. Additionally, the epithelial cells of oyster gills produce immune effectors to defend against pathogens. In light of this, we performed a transcriptome analysis of gill tissues obtained from C. gigas infected with Vibrio alginolyticus for 12 h and 48 h. Through this analysis, we identified 1024 differentially expressed genes (DEGs) at 12 h post-injection and 1079 DEGs at 48 h post-injection. Enrichment analysis of these DEGs revealed a significant association with immune-related Gene Ontology (GO) terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. To further investigate the immune response, we constructed a protein–protein interaction (PPI) network using the DEGs enriched in immune-associated KEGG pathways. This network provided insights into the interactions and relationships among these genes, shedding light on the underlying mechanisms of the innate immune defense mechanism in oyster gills. To ensure the accuracy of our findings, we validated 16 key genes using quantitative RT-PCR. Overall, this study represents the first exploration of the innate immune defense mechanism in oyster gills using a PPI network approach. The findings provide valuable insights for future research on oyster pathogen control and the development of oysters with enhanced antimicrobial resistance. [ABSTRACT FROM AUTHOR]

Tetraploid oysters are artificially produced oysters that do not exist in nature. The successful breeding of 100% triploid oysters resolved the difficulties of traditional drug-induced triploids, such as the presence of drug residues and a low triploid induction rate. However, little is known concerning the biochemical composition and nutrient contents of such tetraploids. Therefore, we investigated compositional differences among diploid, triploid, and tetraploid Crassostrea gigas as well as between males and females of diploids and tetraploids. The findings indicated that glycogen, EPA, ∑PUFA, and omega-3 contents were significantly higher in triploid oysters than in diploids or tetraploids; tetraploid oysters had a significantly higher protein content, C14:0, essential amino acid, and flavor-presenting amino acid contents than diploids or triploids. For both diploid and tetraploids, females had significantly higher levels of glutamate, methionine, and phenylalanine than males but lower levels of glycine and alanine. In addition, female oysters had significantly more EPA, DHA, omega-3, and total fatty acids, a result that may be due to the fact that gonadal development in male oysters requires more energy to sustain growth, consumes greater amounts of nutrients, and accumulates more proteins. With these results, important information is provided on the production of C. gigas, as well as on the basis and backing for the genetic breeding of oysters. [ABSTRACT FROM AUTHOR]

Wound management for acute and chronic wounds has become a serious clinical problem worldwide, placing considerable pressure on public health systems. Owing to the high‐precision, adjustable pore structure, and repeatable manufacturing process, 3D‐printed electrospun fibre (3DP‐ESF) has attracted widespread attention for fabricating wound dressing. In addition, in comparison with 2D electrospun fibre membranes fabricated by traditional electrospinning, the 3D structures provide additional guidance on cell behaviour. In this perspective article, we first summarise the basic manufacturing principles and methods to fabricate 3DP‐ESF. Then, we discuss the function of 3DP‐ESF in manipulating the different stages of wound healing, including anti‐bacteria, anti‐inflammation, and promotion of cell migration and proliferation, as well as the construction of tissue‐engineered scaffolds. In the end, we provide the current challenge faced by 3DP‐ESF in the application of skin wound regeneration and its promising future directions. [ABSTRACT FROM AUTHOR]

The existing object detection algorithms are divided into neural network and non-neural network based methods. Both of them require sufficient training data samples and the consistent environment with the training data to work stably and efficiently. However, they are not able to work if i) there is no object image sample, and/or ii) the working viewports are different from those of the object sampling. To address the above problems, we propose a new method, which includes point-cloud projection (PCP), and equivalent-radius (ER), and the feature-points calibration (FPC) algorithms based on the optical imaging principle. The new PCP algorithm provides a general method to project the point cloud of the object to different viewports for detection. The new ER algorithm uses the output of the PCP algorithm to detect objects. The new FPC algorithm uses markers of a known size to calibrate the viewport parameters of any visual system for the PCP algorithm. Different from the conventional object detection methods and the rendering methods in computer graphics, the new method does not need training samples and thus has less computation. Moreover, it has better generality since it is independent of the viewport locations and angles. Simulation results show that the proposed method works effectively and its object detection accuracy on a standard dataset is above 99.7%, demonstrating that the new method works well without training data, and has a high accuracy even if the working viewports are different from those for object sampling. [ABSTRACT FROM AUTHOR]

In this study, diploid, triploid, and tetraploid Crassostrea gigas samples were subjected to gas chromatography and ion mobility (GC-IMS) to identify and analyze volatile compounds and flavor fingerprints under conditions of high-temperature incubation. The GC-IMS technology identified a total of 54 volatile components in C. gigas. The contents of 1-octen-3-ol, butyl pentanoate, p-methyl anisole, and 2-methyl-2-hepten-6-one in male oysters were significantly higher than in females, while the contents of phenylacetaldehyde, benzaldehyde, 2-ethyl-3-methylpyrazine, 2-ethylfuran, and 2,4-hexadienal in female oysters were significantly higher than in males. The contents of non-3-en-2-one-M and 1-pentanol in diploids were significantly higher than in triploids and tetraploids, while the content of 2,4-hexadienal in tetraploids was significantly higher than in diploids and tetraploids. The contents of ethyl acetate, ethyl-2-butenoate, and butanal in tetraploids were significantly higher than those in diploids and triploids. The results of a principal components analysis showed that different samples were relatively independently clustered, allowing the ability to distinguish different oyster samples. The chemical fingerprints of volatile compounds of C. gigas with different ploidy and gender under high-temperature incubation were established, and the volatile substance contours of C. gigas were visualized. The results provide a reference for distinguishing the ploidy and gender of C. gigas under conditions of high-temperature incubation. [ABSTRACT FROM AUTHOR]

In this study, GC-IMS was used to analyze the volatile component and flavor profiles of Crassostrea gigas individuals of different ploidy and gender. Principal component analysis was used to explore overall differences in flavor profiles, and a total of 54 volatile compounds were identified. The total volatile flavor contents in the edible parts of tetraploid oysters were significantly higher than in diploid and triploid oysters. The concentrations of ethyl (E)-2-butenoate and 1-penten-3-ol were significantly higher in triploid oysters than in diploid and tetraploid oysters. In addition, the volatile compounds propanoic acid, ethyl propanoate, 1-butanol, butanal, and 2-ethyl furan were significantly higher in females than in males. The volatile compounds p-methyl anisole, 3-octanone, 3-octanone, and (E)-2-heptenal were present in higher levels in male than in female oysters. Overall, different ploidy and gender of oysters are connected with different sensory characteristics, providing new insights for understanding the flavor characteristics of oysters. [ABSTRACT FROM AUTHOR]