Manganese is an element essential for living organisms. Development of industrial technologies and exploitation of mineral resources have led to the release of large amount of Mn(Ⅱ) into the environment, posing a serious threat to human health. Bioremediation can remove the Mn(Ⅱ) from the environment rapidly and effectively without generating secondary pollution, thus received increasing attention. This review summarized the diversity and distribution of Mn(Ⅱ) removal microorganisms and the associated mechanisms, followed by discussing the effect of environmental factors on microbial Mn(Ⅱ) removal. Finally, the challenges and prospects for bioremediation of Mn(Ⅱ) polluted wastewater were proposed.
Biodegradation, Environmental ; Humans ; Manganese ; Oxidation-Reduction ; Waste Water

Vascular endothelial cell glycocalyx is a layer of glycoprotein complex located on the surface of endothelial cells, forming a selective permeation barrier on the surface of endothelial cells. In the present review, after a brief introduction of glycocalyx, the relationship between glycocalyx and mass transport under fluid sheer stress (FSS), especially the relationship between glycocalyx and macromolecules such as low density lipoprotein (LDL) has been discussed. This relationship was reflected as following: on the one hand, the thickness and integrity of the glycocalyx affects the concentration polarization of LDL and its transendothelial transport and heparan sulfate proteoglycan (HSPG) participates in the whole process of residual lipoproteins metabolism. On the other hand, ox-LDL, an oxidized product of LDL, destroys heparan sulfate (HS) which is a major component of the endothelial cell glycocalyx. The study on relationship between vascular endothelial glycocalyx and lipoproteins will provide a new clue to elucidate the pathogenesis of atherosclerosis and provide more evidence to view the glycocalyx as a new control target.

Objective To investigate the effect of LAG-3 deficiency (LAG3^-/-) on natural killer (NK) cell function and hepatic fibrosis in mice infected with Echinococcus multilocularis. Methods C57BL/6 mice, each weighing (20 ± 2) g, were divided into the LAG3^-/- and wild type (WT) groups, and each mouse in both groups was inoculated with 3 000 E. multilocularis protoscoleces via the hepatic portal vein. Mouse liver and spleen specimens were collected 12 weeks post-infection, sectioned and stained with sirius red, and the hepatic lesions and fibrosis were observed. Mouse hepatic and splenic lymphocytes were isolated, and flow cytometry was performed to detect the proportions of hepatic and splenic NK cells, the expression of CD44, CD25 and CD69 molecules on NK cell surface, and the secretion of interferon γ (IFN-γ), tumor necrosis factor α (TNF-α), interleukin (IL)-4, IL-10 and IL-17A. Results Sirius red staining showed widening of inflammatory cell bands and hyperplasia of fibrotic connective tissues around mouse hepatic lesions, as well as increased deposition of collagen fibers in the LAG3-/-group relative to the WT group. Flow cytometry revealed lower proportions of mouse hepatic (6.29% ± 1.06% vs. 11.91% ± 1.85%, P < 0.000 1) and splenic NK cells (4.44% ± 1.22% vs. 5.85% ± 1.10%, P > 0.05) in the LAG3^-/- group than in the WT group, and the mean fluorescence intensity of CD44 was higher on the surface of mouse hepatic NK cells in the LAG3^-/- group than in the WT group (t = −3.234, P < 0.01), while no significant differences were found in the mean fluorescence intensity of CD25 or CD69 on the surface of mouse hepaticNK cells between the LAG3^-/- and WT groups (both P values > 0.05). There were significant differences between the LAG3^-/- and WT groups in terms of the percentages of IFN-γ (t = −0.723, P > 0.05), TNF-α (t = −0.659, P > 0.05), IL-4 (t = −0.263, P > 0.05), IL-10 (t = −0.455, P > 0.05) or IL-17A secreted by mouse hepatic NK cells (t = 0.091, P > 0.05), and the percentage of IFN-γ secreted by mouse splenic NK cells was higher in the LAG3^-/- group than in the WT group (58.40% ± 1.64% vs. 50.40% ± 4.13%; t = −4.042, P < 0.01); however, there were no significant differences between the two groups in terms of the proportions of TNF-α (t = −1.902, P > 0.05), IL-4 (t = −1.333, P > 0.05), IL-10 (t = −1.356, P > 0.05) or IL-17A secreted by mouse splenic NK cells (t = 0.529, P > 0.05). Conclusions During the course of E. multilocularis infections, LAG3^-/- promotes high-level secretion of IFN-γ by splenic NK cells, which may participate in the reversal the immune function of NK cells, resulting in aggravation of hepatic fibrosis.