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The hepatopancreas is an important tissue involved in various biological metabolism for molluscs, but its responses to salinity have not been well evaluated. In this study, the dynamic changes of antioxidant, immune function, and apoptosis in the hepatopancreas of Hong Kong oyster (Crassostrea hongkongensis) under high salinity (30 and 35) stress within a 7-day period were analyzed. The data showed that high salinity stress could lead to DNA damage in Hong Kong oyster hemocytes, resulting in an initial up-regulation followed by a decrease in the expression of enzyme-related genes (SOD, GPX) and immune-related genes (SABL, galectin, C3) in the hepatopancreas. Meanwhile, some apoptosis-related genes (Casp-2, P53), heat shock protein-related genes (HSP90), and osmotic pressure-related genes (NaK, CLC7) maintain high expression levels. Correlation analysis indicated that DNA damage showed a negative correlation with the mRNA expression of Casp-3, Casp-2, Casp-8, P53, SABL, galectin, C3, HSP90, HSP70, Na/K, and CLC7, with the negative correlation being particularly strong for the mRNA expression of HSP90 and Na/K. The results enhance the current understanding of the molecular mechanisms of salinity stress responses in Hong Kong oyster. KEY WORDS: Crassostrea hongkongensis, salinity, hepatopancreas, apoptosis, immune function, INTRODUCTION The Hong Kong oyster (Crassostrea hongkongensis), a commercially valuable aquaculture species, is mainly distributed along the northern coast of the South China Sea, yielding up to 130 metric tons [...]

Gender differences in the hemocyte immune response of Hong Kong oyster Crassostrea hongkongensis to Vibrio harveyi and lipopolysaccharide (LPS) infection exist. To determine if a gender difference also exists, we use a 1H NMR-based metabolomics method to investigate responses in C. hongkongensis hepatopancreas tissues to V. harveyi and LPS infection. Both infections induced pronounced gender- and immune-specific metabolic responses in hepatopancreas tissues. Responses are mainly presented in changes in substances involved in energy metabolism (decreased glucose, ATP, and AMP in males and increased ATP and AMP in LPS-infected females), oxidative stress (decreased glutathione in males and decreased tryptophan and phenylalanine and increased choline and proline in LPS-infected females), tricarboxylic acid (TCA) cycle (decreased α-ketoglutarate acid and increased fumarate in LPS-infected males, and decreased fumarate in LPS-infected females), and osmotic regulation (decreased trigonelline and increased taurine in V. harveyi-infected males and decreased betaine in V. harveyi-infected females). Results suggest that post-spawning-phase male oysters have a more significant energy metabolic response and greater ability to cope with oxidative stress than female oysters. We propose that the impact of oyster gender should be taken into consideration in the aftermath of oyster farming or oyster disease in natural seas. [ABSTRACT FROM AUTHOR]

In recent years, more and more studies have shown that early pathogenic bacterial infection in invertebrates can enhance immunity and significantly reduce mortality when reinfected with the same pathogen. There are mechanisms to explain this phenomenon, but they are relatively few. In addition, dose-dependent primary infection is also associated with increased immunity. In the present study, the initial infection dose and mortality of abalone Haliotis diversicolor after reinfection with Vibrio harveyi were recorded, and the mechanism of immune enhancement was investigated by the transcriptomic response of abalone after two successive stimuli with V. harveyi. Priming with different concentrations of pathogen can enhance immunity; however, higher concentration is not always better. Compared with the first exposure, more genes were up-regulated after the second exposure. Among the commonly expressed genes, the immune related genes were significantly or persistently highly expressed after two infections and included pattern recognition receptors as well as immune effectors, such as toll-like receptors, perlucin 4, scavenger receptor class B-like protein, cytochrome P450 1B1-like, glutathione S-transferase 6, lysozyme and so on; in addition, these immune-related genes were mainly distributed in the pathways related to phagocytosis and calcium signaling. Among the specifically expressed genes, compared with the first infection, more genes were involved in the immune, metabolic and digestive pathways after the second infection, which would be more conducive to preventing the invasion of pathogens. This study outlined the mechanism of immune enhancement in abalone after secondary infection at the global molecular level, which is helpful for a comprehensive understanding of the mechanism of immune priming in invertebrates. [ABSTRACT FROM AUTHOR]

Gender differences in individual immune responses to external stimuli have been elucidated in many invertebrates. However, it is unclear if gender differences do exist in the Hong Kong oyster Crassostrea hongkongensis , one of the most valuable marine species cultivated along the coast of South China. To clarify this, we stimulated post-spawning adult C. hongkongensis with Vibrio harveyi and lipopolysaccharide (LPS). Gender-based differences in some essential functional parameters of hemocytes were studied via flow cytometry. Obvious gender-, subpopulation-, and immune-specific alterations were found in the hemocyte immune parameters of C. hongkongensis. Three hemocyte subpopulations were identified: granulocytes, semi-granulocytes, and agranulocytes. Granulocytes, the chief phagocytes and major producers of esterase, reactive oxygen species, and nitric oxide, were the main immunocompetent hemocytes. Immune parameter alterations were notable in the accumulation of granulocyte esterase activities, lysosomal masses, nitric oxide levels, and granulocyte numbers in male oysters. These results suggest that post-spawning-phase male oysters possess a more powerful immune response than females. Gender and subpopulation differences in bivalve immune parameters should be considered in the future analysis of immune parameters when studying the impact of pathogenic or environmental factors. [ABSTRACT FROM AUTHOR]

Biofouling poses severe challenges to pearl oyster Pinctada imbricata culture in China, and controlling it is both labor- and capital-intensive. The antifouling properties of wax, and wax mixed with Chinese herbs, sprayed onto pearl oyster shell surfaces during peak biofouling seasons were evaluated. Pearl oysters coated with three wax treatments (plain wax, Chinaberry seed extract, Chinese honeylocust fruit extract) and a control (no treatment), were cultured in nets for up to 60 days. Mortality rate, fouling organism and pearl-oyster weights, and shell height are reported for individual oysters on each of six sampling dates. With the exception of oysters submerged for 12 days, all oysters were significantly affected by treatment type and submersion duration. Fouling weight increased more rapidly over time in the control-treatment oysters. Wax-based coatings deterred fouling-organism settlement on oysters for at least 2 months during the intensive fouling season, reducing mortality and not adversely effecting growth. [ABSTRACT FROM AUTHOR]

Abstract: An epizootic occurred among cultured golden pompano (Trachinotus ovatus); it involved mass mortality on fish farms in Linshui in Hainan province, China, in 2008. Diseased fish exhibited no obvious clinical signs, but pathological studies showed that nodules were scattered over the spleen and kidney. To investigate the nature of the pathogen, we studied the surviving fish, and a Gram-negative bacterium (designated strain TOS1) was isolated from the spleens of golden pompano. Pathogenicity assays revealed that TOS1 was virulent for golden pompano when they were challenged by intraperitoneal injection, and the lethal dose (LD50) was 1.1×106 colony forming units (CFU)g−1. 16S rDNA gene sequence of TOS1 demonstrated high similarity (99%) to that of Photobacterium damselae subsp. piscicida. Phylogenetic analysis also showed a clear association of strain TOS1 with P. damselae subsp. piscicida, and this agreed with the results of morphological, physiological and biochemical identification. The results also showed that TOS1 was sensitive to norfloxacin, gentamicin, sulfamethoxazole/trimethoprim, neomycin, streptomycin and tetracycline, and was very sensitive to Psidium guajava and Atractylodes lancea (minimum bactericidal concentration, MBC=10−6 g/mL). This paper describes a systematic study of P. damselae subsp. piscicida isolated from diseased golden pompano in China, including its sensitivity to different antibiotics and Chinese herbal extracts, which will contribute to the diagnosis and prevention of the associated disease. [Copyright &y& Elsevier]

The 3D human pituitary organoid represents a promising laboratory model for investigating human pituitary diseases. Nonetheless, this technology is still in its nascent stage, with uncertainties regarding the cellular composition, intercellular interactions, and spatial distribution of the human pituitary organoids. To address these gaps, the culture conditions are systematically adjusted and the efficiency of induced pluripotent stem cells' (iPSCs') differentiation into pituitary organoids is successfully improved, achieving results comparable to or exceeding those of previous studies. Additionally, single-cell RNA-sequencing (scRNA-seq) and stereomics sequencing (Stereo-seq) are performed on the pituitary organoids for the first time, and unveil the diverse cell clusters, intricate intercellular interactions, and spatial information within the organoids. Furthermore, the SOX3 gene interference impedes the iPSCs' differentiation into pituitary organoids, thereby highlighting the potential of pituitary organoids as an ideal experimental model. Altogether, the research provides an optimized protocol for the human pituitary organoid culture and a valuable transcriptomic dataset for future explorations, laying the foundation for subsequent research in the field of pituitary organoids or pituitary diseases., (© 2025 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)

Background: Pituitary stalk interruption syndrome (PSIS) is a complex clinical syndrome characterized by varied pituitary hormone deficiencies, leading to severe manifestations across multiple systems. These include lifelong infertility, short stature, mental retardation, and potentially life-threatening pituitary crises if not promptly diagnosed and treated. Despite extensive research, the precise pathogenesis of PSIS remains unclear. Currently, there are two proposed theories regarding the pathogenic mechanisms: the genetic defect theory and the perinatal injury theory., Methods: We systematically searched English databases (PubMed, Web of Science, Embase) and Chinese databases (CNKI, WanFang Med Online, Sinomed) up to February 24, 2023, to summarize studies on gene sequencing in PSIS patients. Enrichment analyses of reported mutated genes were subsequently performed using the Metascape platform., Results: Our study included 37 articles. KEGG enrichment analysis revealed mutated genes were enriched in the Notch signaling pathway, Wnt signaling pathway, and Hedgehog signaling pathway. GO enrichment analysis demonstrated mutated genes were enriched in biological processes such as embryonic development, brain development, axon development and guidance, and development of other organs., Conclusion: Based on our summary and analyses, we propose a new hypothesis: disruptions in normal embryonic development, partially stemming from the genetic background and/or specific gene mutations in individuals, may increase the likelihood of abnormal fetal deliveries, where different degrees of traction during delivery may lead to different levels of pituitary stalk interruption and posterior lobe ectopia. The clinical diversity observed in PSIS patients may result from a combination of genetic background, specific mutations, and variable degrees of traction during delivery., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The reviewer ZL declared a shared affiliation with the authors SW, DJ, YX, LY, and QG to the handling editor at the time of review., (Copyright © 2024 Wang, Qin, Jiang, Xiao, Ye, Jiang and Guo.)

A new polydorin species, Polydora lingshuiensis sp. n., which is found not only in burrows of pearl oyster shells (shell-boring type) but also in mudtubes on the surface of pearl oyster cages (tube-dwelling type), is described with the use of light microscopy, scanning electron microscopy, and molecular phylogeny. Morphological and molecular distinctions between P. lingshuiensis and other related species reveal that P. lingshuiensis is a valid new species. The reproduction characteristic that the eggs of P. lingshuiensis are gathered together in one hollow cylinder is another piece of evidence confirming that it is indeed a valid new species. Sequence comparisons based on nuclear 18S rDNA, 28S rDNA, and mitochondrial 16S rDNA show that strains of the shell-boring type possess as high as 99.9% to 100% sequence identity relative to those of the tube-dwelling type. This finding evidently indicates that these species types are conspecific. We also find that a comparison of mitochondrial 16S rDNA sequences can provide a higher resolution of polydorin species than those of the nuclear 18S rDNA because the former has a higher interspecific/intraspecific difference ratio. Phylogenetic analyses based on 18S rDNA sequences indicate that all P. lingshuiensis samples group together to forming a sister clade to Polydora uncinata and thus fall within Polydora aura/P. uncinata clade.