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This work investigates the effect of cyclic creep on the long-term oxidation of a directionally-solidified nickel-based superalloy DZ445 up to 1800 h. The stress application of cyclic creep refines the oxides, increases the oxidation weight gain, reduces the oxidation rate exponent, and decreases the activation energy. It enhances the content of Al2O3 and TiO2 in the outermost layer and in the sub-outer layer of CrTaO4 in the film. It delays the formation of the continuous innermost layer of Al2O3 and the sub-inner layer that is rich in Al2O3. The change of phase content and type in the oxidation layers could be ascribed to the diffusion kinetic effect of cyclic creep stress in the superalloy.

ABSTRACT: Four experiments were performed to investigate the role of the mitogen-activated protein kinase (MAPK) signaling pathway in intestinal absorption of phosphorus (P) and calcium (Ca) in broiler chickens. Experiment 1 assessed how dietary levels of 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) influence the gene expression of intestinal P and Ca transporters in broilers. Experiment 2 evaluated the effects of 1,25(OH)2D3 administered via intraperitoneal injection on the extracellular signal-regulated kinase (ERK) and p38 mitogen-activated protein kinase (p38MAPK) signaling pathways. Experiments 3 and 4 investigated the effect of ERK and p38MAPK inhibitors on the expression of intestinal P and Ca transporters. The findings demonstrated that broilers (1–21 days old) fed a 1,25(OH)2D3-deficient diet (0.625 µg/kg) exhibited reduced body weight, tibia P and Ca levels, and mRNA levels of P transporters (NaPi-IIb, PiT-1, and PiT-2), Ca transporters (NCX1, PMCA1b, and CaBP-D28k), vitamin D receptors (VDR), ERK, and p38MAPK in the duodenum (Experiment 1) (P < 0.05). By comparison, the growth, bone quality, and mRNA levels of genes (except for duodenal NaPi-IIb) in broilers were similar to those in broilers fed the control diet when dietary 1,25(OH)2D3 was adequate (5 µg/kg) (Experiment 1) (P > 0.05). After intraperitoneal injection of 1,25(OH)2D3, the mRNA level of jejunal NaPi-IIb and the protein level of p-p38MAPK/t-p38MAPK in broilers (9–14 days old) decreased (P < 0.05), whereas the mRNA level of CaBP-D28k and the protein level of p-ERK/t-ERK increased (Experiment 2) (P < 0.05). The mRNA and protein expression of jejunal NaPi-IIb and the protein expression of CaBP-D28k in broilers (9–17 days old) treated with the ERK inhibitor PD98059 were greater than those in the control group (Experiment 3) (P < 0.05). Similarly, compared with control broilers, broilers (9–17 days old) treated with the p38MAPK inhibitor SB203580 showed elevated mRNA expression of jejunal NaPi-IIb and CaBP-D28k (Experiment 4) (P < 0.05). These results suggest that adequate supplementation with 1,25(OH)2D3 (5 µg/kg) can restore broiler growth and bone quality by upregulating the transcription of genes involved in intestinal P and Ca absorption. Additionally, the ERK and p38MAPK signaling pathways are implicated in the modulatory effect of 1,25(OH)2D3 on the absorption of P and Ca in broilers.

Abstract Compound plant extracts (CPE) are beneficial for aquatic animals on growth performance and antioxidant capacity. A 56‐day experiment was conducted to investigate its positive effect on rice field eel. The fish were fed a commercial diet and supplementing CPE (mainly containing eucommia polysaccharides, reducing sugar) at 0, 0.8, 1.6, 2.4, and 3.2 g/kg. Results showed that dietary CPE significantly increased weight gain and specific growth rate (p

Two experiments were conducted in this research. Experiment 1 investigated the spatial expression characteristics of calcium (Ca) and phosphorus (P) transporters in the duodenum, jejunum, and ileum of 21-day-old broilers provided with adequate nutrient feed. Experiment 2 evaluated the effects of dietary vitamin D3 (VD3) concentration (0, 125, 250, 500, 1,000, and 2,000 IU/kg) on growth performance, bone development, and gene expression levels of intestinal Ca and P transporters in 1–21-day-old broilers provided with the negative control diet without supplemental VD3. Results in experiment 1 showed that the mRNA levels of calcium-binding protein 28-kDa (CaBP-D28k), sodium-calcium exchanger 1 (NCX1), plasma membrane calcium ATPase 1b (PMCA1b), and IIb sodium-phosphate cotransporter (NaPi-IIb) were the highest in the broiler duodenum. By contrast, the mRNA levels of inorganic phosphate transporter 1 (PiT-1) and 2 (PiT-2) were the highest in the ileum. Results in experiment 2 showed that adding 125 IU/kg VD3 increased body weight gain (BWG), feed intake (FI), bone weight, and percentage and weight of Ca and P in the tibia and femur of 1–21-day-old broilers compared with the negative control diet (p < 0.05). The rise in dietary VD3 levels from 125 to 1,000 IU/kg further increased the BWG, FI, and weights of the bone, ash, Ca, and P (p < 0.05). No difference in growth rate and leg bone quality was noted in the broilers provided with 1,000 and 2,000 IU/kg VD3 (p > 0.05). Supplementation with 125–2,000 IU/kg VD3 increased the mRNA abundances of intestinal Ca and P transporters to varying degrees. The mRNA level of CaBP-D28k increased by 536, 1,161, and 28 folds in the duodenum, jejunum, and ileum, respectively, after adding 1,000 IU/kg VD3. The mRNA levels of other Ca and P transporters (PMCA1b, NCX1, NaPi-IIb, PiT-1, and PiT-2) increased by 0.57–1.74 folds by adding 1,000–2,000 IU/kg VD3. These data suggest that intestinal Ca and P transporters are mainly expressed in the duodenum of broilers. Moreover, the addition of VD3 stimulates the two mineral transporter transcription in broiler intestines.

1,25-Dihydroxycholecalciferol (1,25-(OH)2-D3) is the final active product of vitamin D. This study aimed to investigate the effects of 1,25-(OH)2-D3 on growth performance, bone development, and calcium (Ca) transporter gene expression levels in the small intestine of broiler chickens. On the day of hatching, 140 female Ross 308 broilers were randomly allotted into two treatments with five replicates (14 birds per replicate). Two levels of 1,25-(OH)2-D3 (0 and 1.25 µg/kg) were added to the basal diet without vitamin D. Results showed that the addition of 1.25 µg/kg 1,25-(OH)2-D3 increased the average daily feed intake and the average daily gain and decreased the feed conversion ratio and mortality in 1- to 19-day-old broiler chickens compared with the basal diet without vitamin D (P0.05). These data indicate that 1,25-(OH)2-D3 upregulated Ca transporter gene transcription and promoted Ca2+ absorption in the small intestine, especially in the proximal intestine (duodenum and jejunum), thereby improving growth performance and bone mineralization in broiler chickens.

Vascular stem cells exist in the three-layer structure of blood vessel walls and play an indispensable role in angiogenesis under physiological conditions and vascular remodeling under pathological conditions. Vascular stem cells are mostly quiescent, but can be activated in response to injury and participate in endothelial repair and neointima formation. Extensive studies have demonstrated the differentiation potential of stem/progenitor cells to repair endothelium and participate in neointima formation during vascular remodeling. The stem cell population has markers on the surface of the cells that can be used to identify this cell population. The main positive markers include Stem cell antigen-1 (Sca1), Sry-box transcription factor 10 (SOX10). Stromal cell antigen 1 (Stro-1) and Stem cell growth factor receptor kit (c-kit) are still controversial. Different parts of the vessel have different stem cell populations and multiple markers. In this review, we trace the role of vascular stem/progenitor cells in the progression of atherosclerosis and neointima formation, focusing on the expression of stem cell molecular markers that occur during neointima formation and vascular repair, as well as the molecular phenotypic changes that occur during differentiation of different stem cell types. To explore the correlation between stem cell molecular markers and atherosclerotic diseases and neointima formation, summarize the differential changes of molecular phenotype during the differentiation of stem cells into smooth muscle cells and endothelial cells, and further analyze the signaling pathways and molecular mechanisms of stem cells expressing different positive markers participating in intima formation and vascular repair. Summarizing the limitations of stem cells in the prevention and treatment of atherosclerotic diseases and the pressing issues that need to be addressed, we provide a feasible scheme for studying the signaling pathways of vascular stem cells involved in vascular diseases.

Objective This experiment was conducted to determine the chemical composition, digestible energy (DE) and metabolizable energy (ME) contents of corn germ meals (CGM) and to develop equations to predict the corresponding energy contents based on the chemical characteristics of individual CGM. Methods Sixty-six barrows (initial body weight = 51.3±4.6 kg) were allotted to 11 diets including a basal diet and 10 CGM test diets in a completely randomized design. In the test diets, CGM was included in replacement of 30% of the energy-providing ingredients in the basal diet, resulting in a final inclusion rate of 29.1%. Each diet was fed to 6 barrows housed in individual metabolism crates for a 7-d acclimation period followed by a 5-d total but separate collection of feces and urine. Results Considerable variation was observed in acid-hydrolyzed ether extract, ether extract, ash, calcium (Ca) and total phosphorus contents among the CGM samples. On dry matter (DM) basis, the DE and ME contents of the CGM ranged from 10.22 to 15.83 MJ/kg and from 9.94 to 15.43 MJ/kg, respectively. The acid detergent fiber (ADF) contents were negatively correlated with the DE and ME contents of CGM samples. The best-fit prediction equations for the DE and ME values (MJ/kg DM) of the 10 CGM were: DE = 26.85–0.28 insoluble dietary fiber (%)–17.79 Ca (%); ME = 21.05–0.43 ADF (%)–11.40 Ca (%). Conclusion The chemical compositions of CGM vary depending on sources, particularly in ether extract and Ca. The DE and ME values of CGM can be predicted based on their chemical composition in growing pigs.

Commensal microorganisms are essential to the normal development and function of many aspects of animal biology, including digestion, nutrient absorption, immunological development, behaviors, and evolution. The specific microbial composition and evolution of the intestinal tracts of wild pigs remain poorly characterized. This study therefore sought to assess the composition, distribution, and evolution of the intestinal microbiome of wild pigs. For these analyses, 16S rRNA V3-V4 regions from five gut sections prepared from each of three wild sows were sequenced to detect the microbiome composition. These analyses revealed the presence of 6,513 operational taxonomic units (OTUs) mostly distributed across 17 phyla and 163 genera in these samples, with Firmicutes and Actinobacteria being the most prevalent phyla of microbes present in cecum and jejunum samples, respectively. Moreover, the abundance of Actinobacteria in wild pigs was higher than that in domestic pigs. At the genus level the Bifidobacterium and Allobaculum species of microbes were most abundant in all tested gut sections, with higher relative abundance in wild pigs relative to domestic pigs, indicating that in the process of pig evolution, the intestinal microbes also evolved, and changes in the intestinal microbial diversity could have been one of the evolutionary forces of pigs. Intestinal microbial functional analyses also revealed the microbes present in the small intestine (duodenum, jejunum, and ileum) and large intestine (cecum and colon) of wild pigs to engage distinct metabolic spatial structures and pathways relative to one another. Overall, these results offer unique insights that would help to advance the current understanding of how the intestinal microbes interact with the host and affect the evolution of pigs.

ABSTRACT - A 7 × 2 factorial experiment was designed to test the effects of calcium (Ca) to non-phytate phosphorus (NPP) ratio (1.14, 1.43, 1.71, 2.00, 2.29, 2.57, and 2.86) and different sources of vitamin D (1α-hydroxycholecalciferol (1α-OH-D3) and 25-hydroxycholecalciferol (25-OH-D3)) on growth performance and bone mineralization in 1- to 42-d-old broiler chickens. On the day of hatch, 700 female Ross 308 broilers were weighed and randomly assigned to 14 treatments with five stainless steel cages of 10 birds each. Dietary Ca levels were 4.0, 5.0, 6.0, 7.0, 8.0, 9.0, and 10.0 g kg−1 and the NPP content was 3.5 g kg−1. The dose of 1α-OH-D3 or 25-OH-D3 was 5 µg kg−1. Diets were not supplemented with cholecalciferol (vitamin D3). Results showed that the Ca to NPP ratio, vitamin D source, and their interaction affected body weight gain (BWG), feed intake (FI), feed efficiency (FE), and carcass and breast yields, as well as tibia weight and length and ash weight in broiler chickens from 1 to 42 d of age. Broilers fed 1α-OH-D3 had higher BWG and FI as well as tibia breaking strength, weight, length, diameter, and ash weight than birds fed 25-OH-D3 at 42 d of age. The Ca to NPP ratio had a quadratic effect on BWG, FI, mortality, as well as tibia breaking strength, weight, length, ash weight, and ash and P contents in 42-d-old broilers. Broiler chickens at 42 d of age obtain optimal growth performance and bone mineralization at the Ca to NPP ratio of 2.32 when 1α-OH-D3 or 25-OH-D3 are used as the vitamin D source.

This experiment was conducted to determine the effects of inclusion level of soybean oil (SO) and palm oil (PO) on their digestible and metabolism energy (DE and ME) contents when fed to growing pigs by difference and regression method. Sixty-six crossbred growing barrows (Duroc×Landrace×Yorkshire and weighing 38.1±2.4 kg) were randomly allotted to a 2×5 factorial arrangement involving 2 lipid sources (SO and PO), and 5 levels of lipid (2%, 4%, 6%, 8%, and 10%) as well as a basal diet composed of corn and soybean meal. The barrows were housed in individual metabolism crates to facilitate separate collection of feces and urine, and were fed the assigned test diets at 4% of initial body weight per day. A 5-d total collection of feces and urine followed a 7-d diet adaptation period. The results showed that the DE and ME contents of SO and PO determined by the difference method were not affected by inclusion level. The DE and ME determined by the regression method for SO were greater compared with the corresponding respective values for PO (DE: 37.07, ME: 36.79 MJ/kg for SO; DE: 34.11, ME: 33.84 MJ/kg for PO, respectively). These values were close to the DE and ME values determined by the difference method at the 10% inclusion level (DE: 37.31, ME: 36.83 MJ/kg for SO; DE: 34.62, ME: 33.47 MJ/kg for PO, respectively). A similar response for the apparent total tract digestibility of acid-hydrolyzed ether extract (AEE) in lipids was observed. The true total tract digestibility of AEE in SO was significantly (p

Hepatoblastoma is the most frequent liver malignancy in children. HepG2 has been discovered as a hepatoblastoma-derived cell line and tends to form clumps in culture. Intriguingly, we observed that the addition of calcium ions reduced cell clumping and disassociated HepG2 cells. The calcium signal is in connection with a series of processes critical in the tumorigenesis. Here, we demonstrated that extracellular calcium ions induced morphological changes and enhanced the epithelial-mesenchymal transition in HepG2 cells. Mechanistically, calcium ions promoted HepG2 proliferation and migration by up-regulating the phosphorylation levels of focal adhesion kinase (FAK), protein kinase B, and p38 mitogen-activated protein kinase. The inhibitor of FAK or Ca2+/calmodulin-dependent kinase II (CaMKII) reversed the Ca2+-induced effects on HepG2 cells, including cell proliferation and migration, epithelial-mesenchymal transition protein expression levels, and phosphorylation levels of FAK and protein kinase B. Moreover, calcium ions decreased HepG2 cells' sensitivity to cisplatin. Furthermore, we found that the expression levels of FAK and CaMK II were increased in hepatoblastoma. The group with high expression levels of FAK and CaMK II exhibited significantly lower ImmunoScore as well as CD8+ T and NK cells. The expression of CaMK II was positively correlated with that of PDCD1 and LAG3. Correspondingly, the expression of FAK was negatively correlated with that of TNFSF9, TNFRSF4, and TNFRSF18. Collectively, extracellular calcium accelerates HepG2 cell proliferation and migration via FAK and CaMKII and enhances cisplatin resistance. FAK and CaMKII shape immune cell infiltration and responses in tumor microenvironments, thereby serving as potential targets for hepatoblastoma. [ABSTRACT FROM AUTHOR]