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Highly magnetic polymer submicrospheres with a hairy core–shell structure were facilely synthesized by combining distillation–precipitation polymerization (DPP) with subsequent surface-initiated atom transfer radical polymerization (SI-ATRP), and then investigated for protein adsorption. A robust polymer shell consisting of poly(divinylbenzene- co -chloromethylstyrene) (P(DVB- co -CMS)) was coated on superparamagnetic submicrometer-sized magnetite colloid nanocrystal clusters (MCNCs) via DPP. With the benzyl chloride groups on the shell as initiator, poly(2-(dimethylamino) ethyl methacrylate) (PDMAEMA) hairs were grafted by SI-ATRP approach. The resulting hairy core–shell structured Fe 3 O 4 @ P(DVB- co -CMS)–PDMAEMA microspheres showed pH- and temperature-sensitivity, and high-magnetization. The composite microspheres were further investigated for adsorption of a typical acidic protein, i.e. bovine serum albumin (BSA). They exhibited a high binding capacity up to over 660 mg/g (corresponding to 158 DMAEMA monomer units cooperating for binding one BSA molecule) and could rapidly reach binding equilibrium within 5 min. Moreover, the adsorption of BSA was found to be remarkably dependent on the pH and salt concentration of the protein solutions, and the bound protein could be quantitatively desorbed by washing with a medium with lowered pH or raised salt concentration. [ABSTRACT FROM AUTHOR]

Abstract: Plasminogen activator inhibitor (PAI)-1 is a major fibrinolytic inhibitor. High PAI-1 is associated with increased renal and cardiovascular disease risk. Previous studies demonstrated PAI-1 down-regulation by 1,25-dihydroxyvitamin D3 (1,25(OH)2D3), but the molecular mechanism remains unknown. Here we show that exposure of mouse embryonic fibroblasts to TNFα or LPS led to a marked induction of PAI-1, which was blunted by 1,25(OH)2D3, NF-κB inhibitor or p65 siRNA, suggesting the involvement of NF-κB in 1,25(OH)2D3-induced repression. In mouse Pai-1 promoter a putative cis-κB element was identified at −299. EMSA and ChIP assays showed that TNF-α increased p50/p65 binding to this κB site, which was disrupted by 1,25(OH)2D3. Luciferase reporter assays showed that PAI-1 promoter activity was induced by TNFα or LPS, and the induction was blocked by 1,25(OH)2D3. Mutation of the κB site blunted TNFα, LPS or 1,25(OH)2D3 effects. 1,25(OH)2D3 blocked IκBα degradation and arrested p50/p65 nuclear translocation. In mice LPS stimulated PAI-1 expression in the heart and macrophages, and the stimulation was blunted by pre-treatment with a vitamin D analog. Together these data demonstrate that 1,25(OH)2D3 down-regulates PAI-1 by blocking NF-κB activation. Inhibition of PAI-1 production may contribute to the reno- and cardio-protective effects of vitamin D. [Copyright &y& Elsevier]

Abstract Acute lung injury (ALI) is a type of diffuse lung inflammation with a high mortality rate. Studies show that miR-155 plays an important role in inflammation. Here, we investigated the role of miR-155 in lipopolysaccharide (LPS)-induced ALI. The mice with bone marrow transplantation between MiR-155 knockout and wild-type were used as animal models of LPS-induced sepsis. In response to LPS injection, ALI was less severe in miR-155 knockout mice than in wild-type mice, and mainly manifested as reduced pulmonary vascular leakage, pulmonary edema, and neutrophil infiltration. The expression levels of Ang-2 and apoptosis-associated caspases-3 and -9, as well as myosin light chain (MLC) phosphorylation in the lungs were also decreased. A bone marrow transplantation experiment showed that miR-155 expressed in bone marrow-derived lymphocytes rather than lung parenchymal lymphocytes promoted inflammation. Findings suggest that miR-155 expressed in bone marrow-derived lymphocytes promoted LPS-induced ALI through the modulation of the Ang-2-Tie-2 pathway. Highlights • Deletion of miR-155 inhibited the Ang2-Tie2 signaling pathway. • MiR-155 knockout inhibited phosphorylation of MLCK and MLC. • MiR-155 expressed in bone marrow-derived lymphocytes promoted inflammation. [ABSTRACT FROM AUTHOR]

Abstract: Submicron-sized superparamagnetic magnetite colloid nanocrystal clusters (MCNCs) composed of many interconnected tiny Fe3O4 nanoparticles provide a new avenue for constructing highly magnetic polymer submicrospheres for biotechnological and medical applications. Herein, a facile and efficient method is described for the synthesis of Fe3O4@poly(methacrylic acid) (PMAA) core–shell submicrospheres using the MCNCs modified with polymerizable vinyl groups as the submicronic cores. The controlled encapsulation of the MCNCs with PMAA shells was achieved via precipitation polymerization mediated by a reversible addition–fragmentation chain transfer (RAFT) agent. A variety of factors influencing the formation of PMAA layers were examined, such as the loading amounts of the magnetic seeds and monomers, polymerization time, and the MCNCs’ surface chemistry. Compared with previous approaches, much higher seed dosage could be employed in the polymerization system without leading to significant particle conglutination. The shell thickness was readily tailored via varying two synthesis parameters, that is, monomer dosage and reaction time. The resulting hybrid particles showed high saturation magnetization and pH responsiveness. Also, this method was successfully extended to coating other hydrophilic polymer shells over the MCNCs and hence may be a general way for the synthesis of magnetic polymer submicrospheres. [Copyright &y& Elsevier]

1,25-dihydroxyvitamin D 3 and its analog (paricalcitol) have beneficial effects on multiple systems and diseases, including myocarditis. However, the therapeutic effect of cholecalciterol cholesterol emulsion (CCE) on myocarditis and the role of pyroptosis in the progress of myocarditis have not been determined. The objective of this study was to investigate the effect of CCE on experimental autoimmune myocarditis and its underlying mechanisms. The ratio of heart weight to body weight was decreased after CCE treatment compared with vehicle-treated controls. In addition, CCE improved the general status of mice, suppressed myocardial apoptosis, and inhibited the pyroptosis signaling pathway. Therefore, CCE can ameliorate experimental autoimmune myocarditis by downregulating the pyroptosis signaling pathway. [ABSTRACT FROM AUTHOR]

The therapeutic effect of 1,25(OH) 2 vitamin D 3 and its analog (paricalcitol) on experimental colitis in animals has been heavily demonstrated. However, the response to Cholecalciterol Cholesterol Emulsion (CCE), a precursor of 1,25(OH) 2 vitamin D 3 , has not yet been reported. Whether pyroptosis is involved in colitic deterioration also remains unclear. Therefore, we adopted molecular biology and histology approaches to examine mechanisms by which CCE was able to regulate experimental colitis in the animal model induced by 2,4,6-trinitrobenzenesulfonic acid (TNBS). Our data revealed that mice displayed a remarkable reduction in colonic histological scores, colonic inflammation and colonic histological damage. In addition, there was an overall improvement in general status (change in body weight, food and water intake, mental status, activity) and a 30% increase in survival rate due to the downregulation of pyroptosis following treatment with CCE. In conclusion, our data have provided evidence that CCE can attenuate the damage of experimental colitis by suppressing pyroptosis signaling. [ABSTRACT FROM AUTHOR]

Abstract: Dentin matrix protein 1 (DMP1) is expressed in both pulp and odontoblast cells and deletion of the Dmp1 gene leads to defects in odontogenesis and mineralization. The goals of this study were to examine how DMP1 controls dentin mineralization and odontogenesis in vivo. Fluorochrome labeling of dentin in Dmp1-null mice showed a diffuse labeling pattern with a 3-fold reduction in dentin appositional rate compared to controls. Deletion of DMP1 was also associated with abnormalities in the dentinal tubule system and delayed formation of the third molar. Unlike the mineralization defect in Vitamin D receptor-null mice, the mineralization defect in Dmp1-null mice was not rescued by a high calcium and phosphate diet, suggesting a different effect of DMP1 on mineralization. Re-expression of Dmp1 in early and late odontoblasts under control of the Col1a1 promoter rescued the defects in mineralization as well as the defects in the dentinal tubules and third molar development. In contrast, re-expression of Dmp1 in mature odontoblasts, using the Dspp promoter, produced only a partial rescue of the mineralization defects. These data suggest that DMP1 is a key regulator of odontoblast differentiation, formation of the dentin tubular system and mineralization and its expression is required in both early and late odontoblasts for normal odontogenesis to proceed. [Copyright &y& Elsevier]