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Abstract Background To explore potential biomarkers for early diagnosis of atherosclerosis (AS) and provide basic data for further research on AS, the characteristics of serum metabolomics during the progression of AS in mini‐pigs were observed dynamically. Methods An AS model in Bama miniature pigs was established by a high‐cholesterol and high‐fat diet. Fasting serum samples were collected monthly for metabolomics and serum lipid detection. At the end of the treatment period, pathological analysis of the abdominal aorta and coronary artery was performed to evaluate the lesions of AS, thereby distinguishing the susceptibility of mini‐pigs to AS. The metabolomics was detected using a high‐resolution untargeted metabolomic approach. Statistical analysis was used to identify metabolites associated with AS susceptibility. Results Based on pathological analysis, mini‐pigs were divided into two groups: a susceptible group (n = 3) and a non‐susceptible group (n = 6). A total of 1318 metabolites were identified, with significant shifting of metabolic profiles over time in both groups. Dynamic monitoring analysis highlighted 57 metabolites that exhibited an obvious trend of differential changes between two groups with the advance of time. The KEGG (Kyoto Encyclopedia of Genes and Genomes) pathway enrichment analysis indicated significant disorders in cholesterol metabolism, primary bile acid metabolism, histidine metabolism, as well as taurine and hypotaurine metabolism. Conclusions During the progression of AS in mini‐pigs induced by high‐cholesterol/high‐fat diet, the alterations in serum metabolic profile exhibited a time‐dependent pattern, accompanied by notable disturbances in lipid metabolism, cholesterol metabolism, and amino acid metabolism. These metabolites may become potential biomarkers for early diagnosis of AS.

Abstract Background Atherosclerosis is a chronic cardiovascular disease of great concern. However, it is difficult to establish a direct connection between conventional small animal models and clinical practice. The pig's genome, physiology, and anatomy reflect human biology better than other laboratory animals, which is crucial for studying the pathogenesis of atherosclerosis. Methods We used whole‐genome sequencing data from nine Bama minipigs to perform a genome‐wide linkage analysis, and further used bioinformatic tools to filter and identify underlying candidate genes. Candidate gene function prediction was performed using the online prediction tool STRING 12.0. Immunohistochemistry and immunofluorescence were used to detect the expression of proteins encoded by candidate genes. Results We mapped differential single nucleotide polymorphisms (SNPs) to genes and obtained a total of 102 differential genes, then we used GO and KEGG pathway enrichment analysis to identify four candidate genes, including SLA‐1, SLA‐2, SLA‐3, and TAP2. nsSNPs cause changes in the primary and tertiary structures of SLA‐I and TAP2 proteins, the primary structures of these two proteins have undergone amino acid changes, and the tertiary structures also show slight changes. In addition, immunohistochemistry and immunofluorescence results showed that the expression changes of TAP2 protein in coronary arteries showed a trend of increasing from the middle layer to the inner layer. Conclusions We have identified SLA‐I and TAP2 as potential susceptibility genes of atherosclerosis, highlighting the importance of antigen processing and immune response in atherogenesis.

Abstract This study was designed to explore the expression changes of P2Y1 receptors in the distal colonic myenteric layer of rats. An opioid induced constipation(OIC) rat model was generated by intraperitoneal (i.p) injection of loperamide. At 7 days post-treatment, the model rats were assessed by calculating the fecal water content and the gastrointestinal transit ratio. The immunofluorescence (IF)-based histochemical study was used to observe the distribution of P2Y1 receptors in the distal colonic myenteric plexus. Western blotting (WB) was performed to evaluate the expression changes of P2Y1 proteins in the myenteric layer, and the electrophysiological approaches were carried out to determine the regulatory roles of P2Y1 receptors on distal colonic motor function. IF showed that P2Y1 receptors are co-expressed MOR in the enteric nerve cells of the distal colonic myenteric plexus. Moreover, the WB revealed that the protein levels of P2Y1 were significantly decreased in the distal colonic myenteric layer of OIC rats. In vitro tension experiments exhibited that the P2Y1 receptor antagonist MRS2500 enhanced the spontaneous contraction amplitude, adding EM2 and β-FNA did not have any effect on MRS2500. Therefore, P2Y1 receptor expression could be associated with the occurrence of OIC in this rat model and the regulation of colonic motility by MOR may be related to the release of purine neurotransmitters such as ATP in the colonic nervous system.

Carbon nanotubes, as carbon allotropes distinguished by their intricate structures and exceptional physicochemical properties, have demonstrated substantial progress in recent years across diverse domains, including energy production, chemical synthesis, and environmental preservation. They exhibit notable attributes such as high thermal stability, superior adsorption capacity, and a substantial specific surface area, rendering them superb catalyst supports. Particularly in electrochemical energy storage, CNTs are extensively employed in supercapacitor electrodes owing to their elevated electrical conductivity, mechanical robustness, and electrocatalytic prowess, which facilitate significant energy storage capabilities. Their intricate pore architecture and reactive sites make functionalized carbon nanotubes well suited for synthesizing composite materials with diverse components, which are ideal for sequestering carbon dioxide from both atmospheric and indoor environments. This review presents a comprehensive examination of carbon nanotube synthesis methodologies, encompassing chemical vapor deposition, arc discharge, and laser ablation, and evaluates their impacts on the structural and functional properties of carbon nanotubes. Furthermore, this article underscores the applications of carbon nanotubes in fields such as fuel cells, photocatalysis, ammonia synthesis, dry methane reforming, Fischer–Tropsch synthesis, and supercapacitors. Despite the considerable potential of carbon nanotubes, their manufacturing processes remain intricate and costly, impeding large-scale industrial production. This review concludes by addressing the challenges in fabricating carbon nanotube composites and outlining future development prospects.

Abstract Background Hundreds of single‐nucleotide polymorphism (SNP) sites have been found to be potential genetic markers of type 2 diabetes mellitus (T2DM). However, SNPs related to T2DM in minipigs have been less reported. This study aimed to screen the T2DM‐susceptible candidate SNP loci in Bama minipigs so as to improve the success rate of the minipig T2DM model. Methods The genomic DNAs of three Bama minipigs with T2DM, six sibling low‐susceptibility minipigs with T2DM, and three normal control minipigs were compared by whole‐genome sequencing. The T2DM Bama minipig‐specific loci were obtained, and their functions were annotated. Meanwhile, the Biomart software was used to perform homology alignment with T2DM‐related loci obtained from the human genome‐wide association study to screen candidate SNP markers for T2DM in Bama miniature pigs. Results Whole‐genome resequencing detected 6960 specific loci in the minipigs with T2DM, and 13 loci corresponding to 9 diabetes‐related genes were selected. Further, a set of 122 specific loci in 69 orthologous genes of human T2DM candidate genes were obtained in the pigs. Collectively, a batch of T2DM‐susceptible candidate SNP markers in Bama minipigs, covering 16 genes and 135 loci, was established. Conclusions Whole‐genome sequencing and comparative genomics analysis of the orthologous genes in pigs that corresponded to the human T2DM‐related variant loci successfully screened out T2DM‐susceptible candidate markers in Bama miniature pigs. Using these loci to predict the susceptibility of the pigs before constructing an animal model of T2DM may help to establish an ideal animal model.

Key errors of machine tools have a significant impact on their accuracy, however accurately and quickly measuring the geometric errors of machine tools is essential for key error identification. Fortunately, a quick and direct laser measurement method and system for 21 geometric errors of three linear axes of machine tools were proposed previously, which enables the measurement of all 21 geometric errors via a one-step installation and a three-step automated measurement process. Based on this, to efficiently identify the key error factors, this paper first utilizes the 21 geometric errors obtained from the proposed measurement system to evaluate the contribution of each error to the volumetric errors of machine tools, leading to the building of a 21-geometric-error sensitivity analysis model. Then, experiments are carried out on the vertical machining tool TH5656, and all 21 geometric errors are obtained in 5 min. After this, the volumetric error distribution in the machining workspace is mapped according to the relationship between the geometric errors and the machining errors, and the key error factors affecting the manufacturing and machining accuracy of the TH5656 are ultimately determined. Thus, this new method provides a way to quickly identify key errors of the three linear axes of machine tools, and offers guidance for the machine tool configuration design, machining technology determination, and geometric error compensation.

Abstract Background Currently, increasing attention is being paid to the important role of intestinal microbiome in diabetes. However, few studies have evaluated the characteristics of gut microbiome in diabetic miniature pigs, despite it being a good model animal for assessing diabetes. Methods In this study, a mini‐pig diabetes model (DM) was established by 9‐month high‐fat diet (HFD) combined with low‐dose streptozotocin, while the animals fed standard chow diet constituted the control group. 16S ribosomal RNA (rRNA) gene sequencing was performed to assess the characteristics of the intestinal microbiome in diabetic mini‐pigs. Results The results showed that microbial structure in diabetic mini‐pigs was altered, reflected by increases in levels of Coprococcus_3 and Clostridium_sensu_stricto_1, which were positively correlated with diabetes, and decreases in levels of the bacteria Rikenellaceae, Clostridiales_vadinBB60_group, and Bacteroidales_RF16_group, which were inversely correlated with blood glucose and insulin resistance. Moreover, PICRUSt‐predicted pathways related to the glycolysis and Entner‐Doudoroff superpathway, enterobactin biosynthesis, and the l‐tryptophan biosynthesis were significantly elevated in the DM group. Conclusion These results reveal the composition and predictive functions of the intestinal microbiome in the mini‐pig diabetes model, further verifying the relationship between HFD, gut microbiome, and diabetes, and providing novel insights into the application of the mini‐pig diabetes model in gut microbiome research.

In recent years, the greenhouse effect has emerged as a major environmental concern. As a result, the utilization and capture of greenhouse gases have become urgent tasks. The dry reforming of methane (DRM) reaction is a technology that directly converts greenhouse gases (CH4 and CO2) into valuable products. Ni-based catalysts have gained significant attention and industrial prospects in DRM reactions due to their excellent performance and cost-effectiveness compared to noble metals. However, challenges such as metal sintering and carbon deposition hinder its industrialization. This paper provides a review of the recent advancements in catalyst design for DRM reactions, with a focus on the impact of additives, supports, and preparation methods on Ni-based catalysts. It also describes the reaction and deactivation mechanisms, as well as the thermodynamics and kinetics of DRM reactions. Furthermore, this paper envisions the main challenges and opportunities associated with Ni-based catalysts in DRM research.

To investigate the molecular structure and micropore structure of organic matters in coal-measure shale, the black shale samples of the Shanxi formation were collected from Xishan Coalfield, Taiyuan, and a hybrid experimental–simulation method was used for realistic macromolecular models of organic matter (OM). Four experimental techniques were used to determine the structural information of OM, including elemental analysis, state 13C nuclear magnetic resonance (13CNMR), X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared spectroscopy (FTIR). With structural parameters, two-dimensional (2D) average molecular models of OM were established as C177H160O8N2S with a molar weight of 2474, which agreed well with the experimental 13C-NMR spectra. A realistic three-dimensional (3D) OM macromolecular model was also reconstructed, containing 20 2D molecules with a density of 1.41 g/cm3. To determine the connectivity and spatial disposition of the OM pores, focused ion beam microscope (FIB-SEM) and transmission electron micrographs (TEM) were utilized. The 3D OM pores models were developed. The results show that whether the OM pores varied from 20 to 350 nm as obtained from FIB-SEM images or less than 10 nm as observed in the TEM images, both were of poor connectivity. However, the ultra-micro pores from the 3D OM macromolecular model varied from 3Å to 10 Å and showed certain connectivity, which may be the main channel of diffusion. Furthermore, with the pressure increased, the methane adsorption capacity of the 3D OM model increased with a maximum value of 103 cm3/g at 7 MPa, indicating that OM pores less than 1 nm have a huge methane adsorption capacity. Therefore, our work provides an analysis method that is a powerful and superior tool in further research on gas migration.

Abstract Background Miniature pigs are attractive animal models for exploring diabetes because they are similar to humans in terms of physiological structure and metabolism. However, little is known about the complications of diabetes in pigs. Methods In this study, a 28‐month observation of a Wuzhishan miniature pig with streptozotocin (STZ)‐induced (120 mg/kg) diabetes was conducted, to investigate diabetes‐related complications and the possibility of self‐recovery in miniature pigs. Blood glucose, serum and urinary biochemistry was measured, and histopathologic examinations of eyes, kidney and pancreas were made. Results During the observation, diabetic complications of eyes and kidney were observed. The eye complications included bilateral cataracts in the 15th month and degeneration of inner retina and microaneurysm in the 28th month. Kidney complications included glomerular mesangial expansion, focal segmental glomerular sclerosis, and renal tubular epithelial degeneration, but no proteinuria was observed. By 28 months after the application of STZ, with no treatment given, blood glucose had recovered and the number of pancreatic islet beta‐cells had increased significantly. Conclusions We showed that the STZ‐induced diabetes model in miniature pigs could accurately mimic the pathological changes of human diabetes, and that pancreatic islet beta‐cell regeneration did occur in an adult miniature pig, providing a new means for exploring diabetic complications and pancreatic islet beta‐cell regeneration.

As the essential component of shale, clay minerals have a vital influence on the pore structure and the gas content of reservoirs. To investigate the compositional characteristics of coal-measure shale and its effects on pore structure, a total of thirteen Taiyuan formation shale samples were collected from the Qinshui Basin and were analyzed using a combination of X-ray diffraction analysis, X-ray fluorescence spectrometry, Fourier transform infrared spectroscopy (FE-SEM), polarized optical microscopy, and field emission scanning electron microscopy. The results show that the principal minerals of the samples are quartz, kaolinite, and illite. Most of the kaolinite was an original terrigenous detrital material with low crystallinity and a low degree of ordering, whereas the illite was mainly composed of 1Md resulting from diagenesis. Clay minerals developed slits, irregularly-shaped or multisized pores during diagenesis, which can be classed into interlayered pores, intergranular pores, and microfractures. Eight micro-morphological forms of clay minerals were summarized based on FE-SEM observations, such as compacted, parallel, bent, tilted, mutually supporting structures, etc., which are mainly formed by the mechanical compaction of clay minerals with different sizes, shapes, and contact relationships. The diversity and complexity of the micro-morphological forms of clay minerals contribute to the strong heterogeneity, low porosity and high permeability anisotropy of shale.

Objective Adipose tissue is no longer considered as an inert storage organ for lipid, but instead is thought to play an active role in regulating insulin effects via secretion adipokines. However, conflicting reports have emerged regarding the effects of adipokines. In this study, we investigated the role of adipokines in glucose metabolism and insulin sensitivity in obese Bama mini-pigs. Methods An obesity model was established in Bama mini-pigs, by feeding with high-fat and high-sucrose diet for 30 weeks. Plasma glucose and blood biochemistry levels were measured, and intravenous glucose tolerance test was performed. Adipokines, including adiponectin, interleukin-6 (IL-6), resistin and tumor necrosis factor alpha (TNF-α), and glucose-induced insulin secretion were also examined by radioimmunoassay. AMP-activated protein kinase (AMPK) phosphorylation in skeletal muscle, which is a useful insulin resistance marker, was examined by immunoblotting. Additionally, associations of AMPK phosphorylation with plasma adipokines and homeostasis model assessment of insulin resistance (HOMA-IR) index were assessed by Pearce’s correlation analysis. Results Obese pigs showed hyperglycemia, high triglycerides, and insulin resistance. Adiponectin levels were significantly decreased (p

The main objective of this study was observe the distribution and expression of tau in the distal colonic muscle layers using opioid-induced constipation (OIC) rat model and to explore the mechanistic correlation between the tau phosphorylation and occurrence of OIC. The rat model of OIC was generated by intraperitoneal (i.p) injection of loperamide hydrochloride (Lop; 5mg/kg), and was evaluated by examining the fecal properties, intestinal propulsion mobility, immunohistochemistry (IHC), western blot (WB) and ELISA for detecting levels of Tau, P-Ser396-tau, P-Ser404-tau, protein kinase C (PKC), p38 MAPK (p38), p-p38 MAPK (p-p38) and µ-opioid receptors (MORs) in the colonic samples. The gene sequencing approach was used to detect alternatively spliced tau isoforms in the distal colonic muscle layer. Sequencing analysis revealed that 3 isoforms of tau, namely 2N4R, 1N4R and 0N4R were expressed in the distal colonic myocardium tissue. OIC rats had small, dry and hard feces, and intestinal propulsion velocity was significantly slower, especially in the distal colon. P-Ser396-Tau, P-Ser404-Tau, PKC, p-p38, p38, and Tau positive cells were distributed in the intestinal muscle plexus of the distal colon, and all of them were colocalized with MORs; though the expressions levels of tau and p38 remained unchanged, others indexes above significantly increased in the distal colonic muscle layer of OIC rats. However, after the administration of p38 blocker SB203580, OIC rats had salami-like feces, with an increase in colonic propulsion velocities; although the expressions levels of Tau and p38 didn't change significantly in distal colonic muscle layers, the expressions levels of P-Ser396-Tau, P-Ser404-Tau, and p-p38 significantly reduced. To conclude there is a unique distribution pattern of tau within the distal colonic musculature of OIC rats. The abnormal activation of MORs contributes to the hyperphosphorylation of tau protein, which in turn induces the development of OIC. [ABSTRACT FROM AUTHOR]

The modification of noncaking lignite to coking coal was carried out using a CO-subcritical water reaction system, and the surface structure of the modified coal was characterized by X-ray photoelectron spectroscopy. The results show that the caking index (G) of the modified coals increases from 24 to 92 during the progress of catalytic hydromodification. Some oxygen-containing functional groups were removed, decreasing the concentration of C-O, C=O, and COO-. [ABSTRACT FROM AUTHOR]

The laser beam drift is a main factor that influences laser collimation measurement accuracies. In such measurements, the common-path compensation method is an efficient way to eliminate errors which are normally produced by the laser beam drift. Based on our current common-path compensation system, compensations for the laser beam drift were studied by different laser beam radii and detectors. The measurements have shown that the compensation effect for 3 mm beam radius is better than the ones of 1.5 mm and 4.0 mm beam radii. Based on this, the ratio between the 3 mm beam radius and the total area of the quadrant detector, which is 36%, has indicated the best compensation effect. [ABSTRACT FROM AUTHOR]