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As part of this study, laboratory- and pilot-scale washing of soils contaminated with Cr, Cu, Ni, and Zn were performed. The soil washing agents used included strong acids (hydrochloric acid (HCl) and sulfuric acid (H2SO4)) and chelating agents (ethylenediaminetetraacetic acid calcium disodium salt (EDTA) and citric acid (CA)). A positive correlation was observed between the removal efficiency of the washing process and the concentration of the washing solution. Moreover, the effect of H2SO4 on metal removal with respect to concentration variations was more pronounced in the batch studies due mainly to acid dissolution of the heavy metals. Using H2SO4 concentrations of between 300 and 1000 mM, the removal efficiencies achieved when targeting Cr, Cu, Ni, Zn and the total metal content were 41-42, 38-68, 23-25, 47-53, and 42-55%. The removal efficiencies recorded during the engineering pilot scale washing of the field soils using H2SO4 are comparable to those obtained in the batch study. © 2011 American Institute of Chemical Engineers Environ Prog, 2011 [ABSTRACT FROM AUTHOR]

Objectives: To investigate the role and mechanism of epithelial-mesenchymal transition (EMT) in a rat model of bronchopulmonary dysplasia (BPD)., Methods: The experiment consisted of two parts. (1) Forty-eight preterm rats were randomly divided into a normoxia group and a hyperoxia group, with 24 rats in each group. The hyperoxia group was exposed to 85% oxygen to establish a BPD model, while the normoxia group was kept in room air at normal pressure. Lung tissue samples were collected on days 1, 4, 7, and 14 of the experiment. (2) Rat type II alveolar epithelial cells (RLE-6TN) were randomly divided into a normoxia group (cultured in air) and a hyperoxia group (cultured in 95% oxygen), and cell samples were collected 12, 24, and 48 hours after hyperoxia exposure. Hematoxylin-eosin staining was used to observe alveolarization in preterm rat lungs, and immunofluorescence was used to detect the co-localization of surfactant protein C (SPC) and α-smooth muscle actin (α-SMA) in preterm rat lung tissue and RLE-6TN cells. Quantitative real-time polymerase chain reaction and protein immunoblotting were used to detect the expression levels of EMT-related mRNA and proteins in preterm rat lung tissue and RLE-6TN cells., Results: (1) Compared with the normoxia group, the hyperoxia group showed blocked alveolarization and simplified alveolar structure after 7 days of hyperoxia exposure. Co-localization of SPC and α-SMA was observed in lung tissue, with decreased SPC expression and increased α-SMA expression in the hyperoxia group at 7 and 14 days of hyperoxia exposure compared to the normoxia group. In the hyperoxia group, the mRNA and protein levels of TGF-β1, α-SMA, and N-cadherin were increased, while the mRNA and protein levels of SPC and E-cadherin were decreased at 7 and 14 days of hyperoxia exposure compared to the normoxia group ( P <0.05). (2) SPC and α-SMA was observed in RLE-6TN cells, with decreased SPC expression and increased α-SMA expression in the hyperoxia group at 24 and 48 hours of hyperoxia exposure compared to the normoxia group. Compared to the normoxia group, the mRNA and protein levels of SPC and E-cadherin in the hyperoxia group were decreased, while the mRNA and protein levels of TGF-β1, α-SMA, and E-cadherin in the hyperoxia group increased at 48 hours of hyperoxia exposure ( P <0.05)., Conclusions: EMT disrupts the tight connections between alveolar epithelial cells in a preterm rat model of BPD, leading to simplified alveolar structure and abnormal development, and is involved in the development of BPD. Citation:Chinese Journal of Contemporary Pediatrics, 2024, 26(7): 765-773 .

The multiple myeloma (MM), the second most common hematologic malignancy, is malignant proliferative disease of plasma cells. Although the application of many targeted drugs has significantly prolonged the survival time of MM patients, it is still an incurable disease. In recent years, the immunosuppression caused by interaction between tumor microenvironment(TME) and tumor cells has attracted people's attention gradually. As a kind of immunosuppressive cells in TME, regulatory T cells (Treg) play an important role in the progress of MM. Treg is related to the proliferation and metastasis of tumors, and can lead to the progress of MM by promoting the angiogenesis and generating immunosuppressive TME. In this review, we briefly summarized the latest research progress on the impact of Treg on the pathogenesis of MM.

Numerous biomolecules possess α-D-glucosamine as structural component. However, chemical glycosylations aimed at this backbone are usually not easily attained without generating the unwanted β-isomer. We report herein a versatile approach in affording full α-stereoselectivity built upon a carefully selected set of orthogonal protecting groups on a D-glucosaminyl donor. The excellent stereoselectivity provided by the protecting group combination was found independent of leaving groups and activators. With the trichloroacetimidate as the optimum donor leaving group, core skeletons of glycosylphosphatidyl inositol anchors, heparosan, heparan sulfate, and heparin were efficiently assembled. The orthogonal protecting groups were successfully manipulated to further carry out the total syntheses of heparosan tri- and pentasaccharides and heparin di-, tetra-, hexa-, and octasaccharide analogues. Using the heparin analogues, heparin-binding hemagglutinin, a virulence factor of Mycobacterium tuberculosis, was found to bind at least six sugar units with the interaction notably being entropically driven.