Cellular evidence and spatial distribution of endosomal biosynthesis and autophagy in intestinal immune barrier cells of crucian carp (Carassiuscarassius).

Crucian carp (Carassius carassius) is an important aquatic economic animal, and the immune barrier function of its intestine has been a focus of research into oral vaccines and drugs. However, the histological structures of the intestinal barrier and its adjacent areas have not been clearly established, and little subcellular evidence is available to elucidate the spatial distribution of intracellular biological processes. In this study, the spatial distribution of autophagy and endosome formation in the intestinal epithelial cells (IECs) of crucian carp were analyzed. These two biological activities are closely related to intestinal homeostasis, immunity, and cell communication. Periodic acid-Schiff (PAS) and Masson's trichrome staining were employed to elucidate the distinctive histological framework of the Crucian carp's myoid cell network, which resides within the subepithelial layer and is characterized by gap junctions. Transmission electron microscopy (TEM), immunohistochemistry (IHC), and immunofluorescence (IF) were used to detect the structural and functional aspects of the IEC in different intestinal segments. TEM and immunohistochemical analyses captured the biogenesis and maturation of early and late endosomes as well as multivesicular bodies (MVBs), as well as the initiation and progression of autophagy, including macroautophagy and mitophagy. The endosome and MVBs-specific marker CD63 and autophagy-related protein LC3 were highly expressed in IECs and were correlated with autophagy and endosome biosynthesis in the apical and basal regions of individual cells, and differed between different intestinal segments. In summary, this study elucidated the ubiquity and morphological characteristics of autophagy and endosome formation across different intestinal segments of crucian carp. A unique myoid cell network beneath the intestinal epithelium in crucian carp was also identified, expanding the histological understanding of this animal's intestinal tract.

Cellular evidence of mucus cell immunological and differentiation characteristics in allogeneic crucian carp intestinal lamina propria.

The allogeneic crucian carp is an important fish farm animal with a very different digestive system structure from that of mammals. The lamina propria of the fish intestine is also considered to be an important site of intestinal immunity in fish, but functional histological studies of the lamina propria of the allogeneic crucian carp intestine are still lacking. In this study, Identification of the ubiquitous lamina propria mucus cells in the lamina propria of the intestine by hematoxylin-eosin staining, and determination of the mucocytic properties, class, and distribution of these cells in each intestinal segment by Alcian Blue-Periodic Acid-Schiff (AB-PAS) staining. The results show that type III mucus cells were abundant in the lamina propria of the foregut and midgut, while type II and type IV mucus cells predominate in the hindgut, possibly reflecting the distinct functions of these intestinal segments. Transmission electron microscopy dissected the differentiation of mucus cells in the lamina propria of the intestine at the ultrastructural level and investigated their morphology and distribution patterns in different intestinal segments, the findings revealed that lamina propria mucus cells perform rudimentary functions such as mucous secretion, phagocytosis, and degradation functions. Moreover, immunohistochemistry labeling with CD68 and LAMP1 revealed that numerous cells in the anterior, middle, and posterior intestines were positive for both proteins. Immunofluorescence double-labeling demonstrated that these cells highly co-expressed CD68 and LAMP1. Besides, the distribution and morphology of CD68+ and LAMP1+ cells were similar to those of AB-PAS positive cells and they accounted for the majority of parenchyma cells. Considering the above results, there were abundant cells with both mucous secretion and phagocytosis in the intestinal lamina propria of allogeneic crucian carp, which are a essential component of the intestinal immune process of allogeneic crucian carp.

Atherosclerosis-related biomarker PABPC1 predicts pan-cancer events.

BACKGROUND: Atherosclerosis (AS) and tumours are the leading causes of death worldwide and share common risk factors, detection methods and molecular markers. Therefore, searching for serum markers shared by AS and tumours is beneficial to the early diagnosis of patients. METHODS: The sera of 23 patients with AS-related transient ischaemic attack were screened by serological identification of antigens through recombinant cDNA expression cloning (SEREX), and cDNA clones were identified. Pathway function enrichment analysis was performed on cDNA clones to identify their biological pathways and determine whether they were related to AS or tumours. Subsequently, gene-gene and protein-protein interactions were performed and AS-associated markers would be discovered. The expression of AS biomarkers in human normal organs and pan-cancer tumour tissues were explored. Then, immune infiltration level and tumour mutation burden of various immune cells were evaluated. Survival curves analysis could show the expression of AS markers in pan-cancer. RESULTS: AS-related sera were screened by SEREX, and 83 cDNA clones with high homology were obtained. Through functional enrichment analysis, it was found that their functions were closely related to AS and tumour functions. After multiple biological information interaction screening and the external cohort validating, poly(A) binding protein cytoplasmic 1 (PABPC1) was found to be a potential AS biomarker. To assess whether PABPC1 was related to pan-cancer, its expression in different tumour pathological stages and ages was screened. Since AS-associated proteins were closely related to cancer immune infiltration, we investigated and found that PABPC1 had the same role in pan-cancer. Finally, analysis of Kaplan-Meier survival curves revealed that high PABPC1 expression in pan-cancer was associated with high risk of death. CONCLUSIONS: Through the findings of SEREX and bioinformatics pan-cancer analysis, we concluded that PABPC1 might serve as a potential biomarker for the prediction and diagnosis of AS and pan-cancer.

Serum Anti-BRAT1 is a Common Molecular Biomarker for Gastrointestinal Cancers and Atherosclerosis.

Atherosclerosis (AS) and cancers are major global causes of mortality and morbidity. They also share common modifiable pathogenesis risk factors. As the same strategies used to predict AS could also detect certain cancers, we sought novel serum antibody biomarkers of cancers in atherosclerotic sera sampled by liquid biopsy. Using serological antigen identification by cDNA expression cloning (SEREX) and western blot, we screened and detected the antigens BRCA1-Associated ATM Activator 1 (BRAT1) and WD Repeat Domain 1 (WDR1) in the sera of patients with transient ischemic attacks (TIA). Amplified luminescence proximity homogeneous assay-linked immunosorbent assay (AlphaLISA) established the upregulation of serum BRAT1 antibody (BRAT1-Abs) and WDR1 antibody (WDR1-Abs) in patients with AS-related diseases compared with healthy subjects. ROC and Spearman's correlation analyses showed that BRAT1-Abs and WDR1-Abs could detect AS-related diseases. Thus, serum BRAT1-Abs and WDR1-Abs are potential AS biomarkers. We used online databases and AlphaLISA detection to compare relative antigen and serum antibody expression and found high BRAT1 and BRAT1-Abs expression in patients with GI cancers. Significant increases (> 0.6) in the AUC for BRAT1-Ab vs. esophageal squamous cell carcinoma (ESCC), gastric cancer, and colorectal cancer suggested that BRAT1-Ab exhibited better predictive potential for GI cancers than WDR1-Ab. There was no significant difference in overall survival (OS) between BRAT1-Ab groups (P = 0.12). Nevertheless, a log-rank test disclosed that the highest serum BRAT1-Ab levels were associated with poor ESCC prognosis at 5-60 weeks post-surgery. We validated the foregoing conclusions by comparing serum BRAT1-Ab and WDR1-Ab levels based on the clinicopathological characteristics of the patients with ESCC. Multiple statistical approaches established a correlation between serum BRAT1-Ab levels and platelet counts. BRAT1-Ab upregulation may enable early detection of AS and GI cancers and facilitate the delay of disease progression. Thus, BRAT1-Ab is a potential antibody biomarker for the diagnosis of AS and GI cancers and strongly supports the routine clinical application of liquid biopsy in chronic disease detection and diagnosis.

HDAC1-mediated deacetylation of HIF1α prevents atherosclerosis progression by promoting miR-224-3p-mediated inhibition of FOSL2.

We intended to characterize functional relevance of microRNA (miR)-224-3p in endothelial cell (EC) apoptosis and reactive oxygen species (ROS) accumulation in atherosclerosis, considering also the integral involvement of histone deacetylase 1 (HDAC1)-mediated hypoxia-inducible factor-1α (HIF1α) deacetylation. The binding affinity between miR-224-3p and Fos-like antigen 2 (FOSL2) was predicted and validated. Furthermore, we manipulated miR-224-3p, FOSL2, HDAC1, and HIF1α expression in oxidized low-density lipoprotein (ox-LDL)-induced ECs, aiming to clarify their effects on cell activities, inflammation, and ROS level. Additionally, we examined the impact of miR-224-3p on aortic atherosclerotic plaque and lesions in a high-fat-diet-induced atherosclerosis model in ApoE-/- mice. Clinical atherosclerotic samples and ox-LDL-induced human aortic ECs (HAECs) exhibited low HDAC1/miR-224-3p expression and high HIF1α/FOSL2 expression. miR-224-3p repressed EC cell apoptosis, inflammatory responses, and intracellular ROS levels through targeting FOSL2. HIF1α reduced miR-224-3p expression to accelerate EC apoptosis and ROS accumulation. Moreover, HDAC1 inhibited HIF1α expression by deacetylation, which in turn enhanced miR-224-3p expression to attenuate EC apoptosis and ROS accumulation. miR-224-3p overexpression reduced atherosclerotic lesions in vivo. In summary, HDAC1 overexpression may enhance the anti-atherosclerotic and endothelial-protective effects of miR-224-3p-mediated inhibition of FOSL2 by deacetylating HIF1α, underscoring a novel therapeutic insight against experimental atherosclerosis.

[Particulate Component Emission Characteristic from a Diesel Bus with DOC and CDPF].

A diesel bus was tested with a China City Bus Cycle (CCBC) on a heavy chassis dynamometer, and the components of the particulate emissions with different after-treatment equipment were investigated. Results showed that OC was less than EC in the particulates of the bus emissions without the use of after-treatment equipment. The organic components were mainly fatty acids (60.9%) and n-alkanes (32.4%), with a few hopanes and PAHs. Fatty acid components were mainly C16:0, C18, C14, and C18:1. The n-alkanes were mainly C18-C24, with C21H44 and C22H46 accounting for the greatest portion. PAH mass was concentrated in medium and small molecular weight components, such as Pyr, FL, and PA. While PAH toxicity was dominated by medium and high molecular weight components, BaP was the most toxic, followed by B(b+k)F, BaA, and IcdP. The total toxicity of the PAHs decreased by 2.7% after DOC treatment and continued to decrease by 89.6%-93.8% after CDPF treatment. After-treatment equipment significantly reduced the OC+EC emissions by 18.9% (DOC) and 70.5%-72.5% (CDPF), but the reduction rate varied from one component to another. The different precious metal loadings of the CDPF did not obviously affect the reduction rate.

[Effects of Different Precious Metal Loads of CDPF on Characteristics of VOCs Emissions from a Diesel Bus].

Based on heavy chassis dynamometers, an experimental study was conducted in a diesel bus with proton transfer reaction mass spectrometry (PTR-MS). It investigated the effects of volatile organic compound (VOC) emission characteristics with three different diesel oxidation catalyst (DOC)+catalyzed diesel particulate filter (CDPF) after-treatments for a typical Chinese city bus driving cycle (CCBC). The results reveal that the major compounds from the diesel bus are OVOCs, aromatic hydrocarbons, alkenes, alkanes, nitrogenous organic compounds, and polycyclic aromatic hydrocarbons (PAH), and that the OVOCs account for more than 50%of the total VOCs. With the same precious metal composition and ratio of the proportion in the CDPF catalyst, the emissions of VOCs decrease with an increase in precious metal load. The emission reduction rates of the VOCs are 36.2%, 40.1%, and 41.4%, respectively, when the precious metal loads are 15 g·ft-3 (type A after-treatment device), 25 g·ft-3 (type B), and 35 g·ft-3 (type C). The average emission rates of alkanes for the three kinds of DOC+CDPF after-treatments are all over 59% for the entire CCBC cycle. The type C after-treatment device can reduce the alkane emissions by 70.2%, with a slight advantage for the OVOC reduction compared with type A and type B devices. For unsaturated hydrocarbons, including aromatic hydrocarbons, alkenes, and PAHs, the after-treatment devices have a catalytic effect, but there is no significant difference between them. The emissions of nitrogenous organic compounds are greatly decreased, by 50.5%, with the type A after-treatment, but the reduction rate decreases with an increase in precious metal load. In addition, OVOCs, aromatic hydrocarbons, and alkenes are the most important contributors to ozone formation. The adoption of DOC+CDPF reduces the emissions of VOCs and, therefore, the ozone formation potential. Taking into account the emission reduction rates and costs of the three different after-treatments and for weighting coefficients of 0.8 and 0.2, respectively, the type B after-treatment is the optimal solution.