38 research outputs found
Comparative analysis of load responses and deformation for crust composite foundation and pile-supported embankment
Ground improvement using artificial crust composite foundation, consisting of stabilization of soft clay and composite foundation, is an effective technique for the treatment of deep soft soil layers under infrastructure embankments. In this study, the load responses and settlement performance of this improvement technique were investigated using two centrifuge model tests to compare the variations of the vertical deformation, pore water pressure, axial force of the piles and tensile stress at the bottom of the artificial crust in the crust composite foundation with those in pile-supported embankment. The results of centrifuge model tests showed that the load responses and settlement performance of artificial crust composite foundation was different from the pile-supported embankment, which displayed mainly that the final middle settlement of crust composite foundation can be reduced by about 15% compared with those of pile-supported embankment with the same length of pile and construction cost. The deformation of the crust with the characteristics of the plate was found based on the change of the tensile stress. Additionally, the excess pore water pressure in the crust composite foundation was lower owing to the stress diffusion effect of the crust during the loading period and the dissipation rate of excess pore water pressure was slower due to lower permeability of the crust at the same loading period. Eventually, the axial force of the middle piles was reduced. At the same time, the boundary stress was functioned with the crust, the axial force of the side piles was improved. The comparison of measured and calculated results was carried out using the stress reduction ratio, the result shows that the bearing capacity of the subsoil in the crust composite was improved
Effect of Gelsemium elegans
Gelsemium elegans (GE) is a kind of well-known toxic plant. It can be detoxified by Mussaenda pubescens (MP), but the detoxification mechanism is still unclear. Thus, a detoxification herbal formula (GM) comprising GE and MP was derived. The Caco-2 cells monolayer model was used to evaluate GM effects on transporting six kinds of indole alkaloids of GE. The bidirectional transport studies demonstrated that absorbance percentage of indole alkaloids in GE increased linearly over time. But in GM, Papp (AP→BL) values of the most toxic members, gelsenicine, humantenidine, and gelsevirine, were lower than that of Papp (BL→AP) (P<0.05). The prominent analgesic effect members, gelsemine and koumine, were approximately 1.00 in γ values. Nowhere was this increasing efflux more pronounced than in the case of indole alkaloids with N-O structure. In the presence of verapamil, the γ values of humantenidine, gelsenicine, gelsevirine, and humantenine were decreased by 43.69, 41.42, 36.00, and 8.90 percent, respectively. The γ values in presence of ciclosporin were homologous with a decrease of 42.32, 40.59, 34.00, and 15.07 percent. It suggested that the efflux transport was affected by transporters. Taken together, due to the efflux transporters participation, the increasing efflux of indole alkaloids from GM was found in Caco-2 cells
From trash to treasure: the role of bacterial extracellular vesicles in gut health and disease
Bacterial extracellular vesicles (BEVs) have emerged as critical factors involved in gut health regulation, transcending their traditional roles as byproducts of bacterial metabolism. These vesicles function as cargo carriers and contribute to various aspects of intestinal homeostasis, including microbial balance, antimicrobial peptide secretion, physical barrier integrity, and immune system activation. Therefore, any imbalance in BEV production can cause several gut-related issues including intestinal infection, inflammatory bowel disease, metabolic dysregulation, and even cancer. BEVs derived from beneficial or commensal bacteria can act as potent immune regulators and have been implicated in maintaining gut health. They also show promise for future clinical applications in vaccine development and tumor immunotherapy. This review examines the multifaceted role of BEVs in gut health and disease, and also delves into future research directions and potential applications
Transcriptional activation of follistatin by Nrf2 protects pulmonary epithelial cells against silica nanoparticle-induced oxidative stress
Silica nanoparticles (SiO2 NPs) cause oxidative stress in respiratory system. Meanwhile, human cells launch adaptive responses to overcome SiO2 NP toxicity. However, besides a few examples, the regulation of SiO2 NP-responsive proteins and their functions in SiO2 NP response remain largely unknown. In this study, we demonstrated that SiO2 NP induced the expression of follistatin (FST), a stress responsive gene, in mouse lung tissue as well as in human lung epithelial cells (A549). The levels of Ac-H3(K9/18) and H3K4me2, two active gene markers, at FST promoter region were significantly increased during SiO2 NP treatment. The induction of FST transcription was mediated by the nuclear factor erythroid 2-related factor 2 (Nrf2), as evidenced by the decreased FST expression in Nrf2-deficient cells and the direct binding of Nrf2 to FST promoter region. Down-regulation of FST promoted SiO2 NP-induced apoptosis both in cultured cells and in mouse lung tissue. Furthermore, knockdown of FST increased while overexpression of FST decreased the expression level of NADPH oxidase 1 (NOX1) and NOX5 as well as the production of cellular reactive oxygen species (ROS). Taken together, these findings demonstrated a protective role of FST in SiO2 NP-induced oxidative stress and shed light on the interaction between SiO2 NPs and biological systems
Clinical factors of post-chemoradiotherapy as valuable indicators for pathological complete response in locally advanced rectal cancer
OBJECTIVES: Pathological complete response has shown a better prognosis for patients with locally advanced rectal cancer after preoperative chemoradiotherapy. However, correlations between post-chemoradiotherapy clinical factors and pathologic complete response are not well confirmed. The aim of the current study was to identify post-chemoradiotherapy clinical factors that could serve as indicators of pathologic complete response in locally advanced rectal cancer. METHODS: This study retrospectively analyzed 544 consecutive patients with locally advanced rectal cancer treated at Sun Yat-sen University Cancer Center from December 2003 to June 2014. All patients received preoperative chemoradiotherapy followed by surgery. Univariate and multivariate regression analyses were performed to identify post-chemoradiotherapy clinical factors that are significant indicators of pathologic complete response. RESULTS: In this study, 126 of 544 patients (23.2%) achieved pathological complete response. In multivariate analyses, increased pathological complete response rate was significantly associated with the following factors: post-chemoradiotherapy clinical T stage 0-2 (odds ratio=2.098, 95% confidence interval=1.023-4.304, p=0.043), post-chemoradiotherapy clinical N stage 0 (odds ratio=2.011, 95% confidence interval=1.264-3.201, p=0.003), interval from completion of preoperative chemoradiotherapy to surgery of >;7 weeks (odds ratio=1.795, 95% confidence interval=1.151-2.801, p=0.010) and post-chemoradiotherapy carcinoembryonic antigen ≤2 ng/ml (odds ratio=1.579, 95% confidence interval=1.026-2.432, p=0.038). CONCLUSIONS: Post-chemoradiotherapy clinical T stage 0-2, post-chemoradiotherapy clinical N stage 0, interval from completion of chemoradiotherapy to surgery of >;7 weeks and post-chemoradiotherapy carcinoembryonic antigen ≤2 ng/ml were independent clinical indicators for pathological complete response. These findings demonstrate that post-chemoradiotherapy clinical factors could be valuable for post-operative assessment of pathological complete response
Delineating the molecular landscape of different histopathological growth patterns in colorectal cancer liver metastases
BackgroundHistopathological growth patterns (HGPs) have shown important prognostic values for patients with colorectal cancer liver metastases, but the potential molecular mechanisms remain largely unknown.MethodsWe performed an exploratory analysis by conducting the RNA sequencing of primary colorectal lesions, colorectal liver metastatic lesions and normal liver tissues.FindingsWe found that desmoplastic HGPs of the metastatic lesions were significantly enriched in EMT, angiogenesis, stroma, and immune signaling pathways, while replacement HGPs were enriched in metabolism, cell cycle, and DNA damage repair pathways. With the exception of immune-related genes, the differentially expressed genes of the two HGPs from colorectal liver metastases were mostly inherited from the primary tumor. Moreover, normal liver tissue in the desmoplastic HGP subgroup was markedly enriched in the fibrinous inflammation pathway.ConclusionsWe surmised that HGPs are observable morphological changes resulting from the regulation of molecular expressions, which is the combined effect of the heterogeneity and remodeling of primary tumors seeds and liver soils
Specific microRNAs as novel biomarkers for combination chemotherapy resistance detection of colon adenocarcinoma
Effect of Gelsemium elegans and Mussaenda pubescens, the Components of a Detoxification Herbal Formula, on Disturbance of the Intestinal Absorptions of Indole Alkaloids in Caco-2 Cells
Gelsemium elegans (GE) is a kind of well-known toxic plant. It can be detoxified by Mussaenda pubescens (MP), but the detoxification mechanism is still unclear. Thus, a detoxification herbal formula (GM) comprising GE and MP was derived. The Caco-2 cells monolayer model was used to evaluate GM effects on transporting six kinds of indole alkaloids of GE. The bidirectional transport studies demonstrated that absorbance percentage of indole alkaloids in GE increased linearly over time. But in GM, Papp (AP→BL) values of the most toxic members, gelsenicine, humantenidine, and gelsevirine, were lower than that of Papp (BL→AP) (P<0.05). The prominent analgesic effect members, gelsemine and koumine, were approximately 1.00 in γ values. Nowhere was this increasing efflux more pronounced than in the case of indole alkaloids with N-O structure. In the presence of verapamil, the γ values of humantenidine, gelsenicine, gelsevirine, and humantenine were decreased by 43.69, 41.42, 36.00, and 8.90 percent, respectively. The γ values in presence of ciclosporin were homologous with a decrease of 42.32, 40.59, 34.00, and 15.07 percent. It suggested that the efflux transport was affected by transporters. Taken together, due to the efflux transporters participation, the increasing efflux of indole alkaloids from GM was found in Caco-2 cells
Innovation-Driven Development and Urban Land Low-Carbon Use Efficiency: A Policy Assessment from China
Improving the low-carbon utilization efficiency of urban land is crucial to the low-carbon transformation and sustainable development of China and the world economy. Innovation-driven development, especially the construction of National Independent Innovation Demonstration Zones (NIIDZs), is an important measure to realize the low-carbon transformation of urban land use and sustainable economic development in China. However, previous studies have neglected to study the impact of the construction of NIIDZs on the low-carbon utilization efficiency of urban land. Based on a theoretical analysis and using the panel data of 283 cities in China from 2006 to 2019, we took NIIDZ construction in China as a quasi-natural experiment and adopted the progressive difference-in-differences method (DID) to evaluate the impact and action mechanism of NIIDZ construction on urban land low-carbon utilization efficiency. We found that NIIDZ construction can significantly promote the improvement of the low-carbon utilization efficiency of urban land, and a series of robustness analysis results support this research conclusion. With the passage of time, this kind of promotion effect shows a trend of increasing fluctuation. NIIDZ construction mainly improves the low-carbon utilization efficiency of urban land by promoting green technology innovation and generating economies of scale. In addition, compared with eastern cities, small-scale cities and resource-based cities, the promotion effect of NIIDZ construction in central and western cities, large cities, and non-resource-based cities is more obvious. This study provides a theoretical basis and practical reference for the low-carbon utilization of urban land from the perspective of innovation in China
Innovation-Driven Development and Urban Land Low-Carbon Use Efficiency: A Policy Assessment from China
Improving the low-carbon utilization efficiency of urban land is crucial to the low-carbon transformation and sustainable development of China and the world economy. Innovation-driven development, especially the construction of National Independent Innovation Demonstration Zones (NIIDZs), is an important measure to realize the low-carbon transformation of urban land use and sustainable economic development in China. However, previous studies have neglected to study the impact of the construction of NIIDZs on the low-carbon utilization efficiency of urban land. Based on a theoretical analysis and using the panel data of 283 cities in China from 2006 to 2019, we took NIIDZ construction in China as a quasi-natural experiment and adopted the progressive difference-in-differences method (DID) to evaluate the impact and action mechanism of NIIDZ construction on urban land low-carbon utilization efficiency. We found that NIIDZ construction can significantly promote the improvement of the low-carbon utilization efficiency of urban land, and a series of robustness analysis results support this research conclusion. With the passage of time, this kind of promotion effect shows a trend of increasing fluctuation. NIIDZ construction mainly improves the low-carbon utilization efficiency of urban land by promoting green technology innovation and generating economies of scale. In addition, compared with eastern cities, small-scale cities and resource-based cities, the promotion effect of NIIDZ construction in central and western cities, large cities, and non-resource-based cities is more obvious. This study provides a theoretical basis and practical reference for the low-carbon utilization of urban land from the perspective of innovation in China