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Abstract: Dentin sialoprotein (DSP) is cleaved from dentin sialophosphoprotein (DSPP) and most abundant dentinal non-collagenous proteins in dentin. DSP is believed to participate in differentiation and mineralization of cells. In this study, we first constructed recombinant human DSP (rhDSP) in Escherichia coli (E. coli) and investigated its odontoblastic differentiation effects on human dental pulp cells (hDPCs). Cell adhesion activity was measured by crystal violet assay and cell proliferation activity was measured by MTT assay. To assess mineralization activity of rhDSP, Alizarin Red S staining was performed. In addition, the mRNA levels of collagen type І (Col І), alkaline phosphatase (ALP), and osteocalcin (OCN) were measured due to their use as mineralization markers for odontoblast-/osteoblast-like differentiation of hDPCs. The obtained rhDSP in E. coli was approximately identified by SDS–PAGE and Western blot. Initially, rhDSP significantly enhanced hDPCs adhesion activity and proliferation (p< 0.05). In Alizarin Red S staining, stained hDPCs increased in a time-dependent manner. This odontoblastic differentiation activity was also verified through mRNA levels of odontoblast-related markers. Here, we first demonstrated that rhDSP may be an important regulatory ECM in determining the hDPCs fate including cell adhesion, proliferation, and odontoblastic differentiation activity. These findings indicate that rhDSP can induce growth and differentiation on hDPCs, leading to improve tooth repair and regeneration. [Copyright &y& Elsevier]

[Display omitted] Hepatitis B virus (HBV) infection is closely associated with the high risk of evolving into human hepatitis diseases including chronic hepatitis, liver fibrosis and cirrhosis, as well as hepatoma. Although various methods have been developed for HBV DNA detection, most of them either rely on expensive instruments or laborious procedures involving professional personnel. In this study, we for the first time established the CRISPR-Cas12a based colorimetric biosensor for target HBV detection by utilizing probe DNA regulation of the catalytic behaviors of Mxene-probe DNA-Ag/Pt nanohybrids. In the presence of HBV target, the Cas12a trans -cleavage activity could be efficiently activated to degrade the DNA probes, which led to the inhibition of DNA metallization and enzyme activity enhancer DNA adsorbed on Mxene, resulting in significantly reduced catalytic activity. The Mxene-probe DNA-Ag/Pt nanohybrids exhibited excellent sensitivity and specificity with subpicomolar detection limits, as well as good accuracy and stability for the determination of target HBV DNA in human serum samples. Moreover, this colorimetric sensing strategy could be integrated with the smartphone platform to allow the visible sensitive detection of target DNA. Taken together, the proposed colorimetric method provides a novel approach for HBV DNA diagnosis, especially suitable for the high endemic, developing countries with limited instrumental and medical supports. [ABSTRACT FROM AUTHOR]

In isolated cardiac sarcoplasmic reticulum (SR) vesicles, methyl methacrylate (2.5–100 mM) directly inhibited initial rates of Ca2+ uptake as well as the maximal uptake. Inhibition of SR Ca2+ uptake by methyl methacrylate was concentration-dependent, and the highest concentration of methyl methacrylate (100 mM) almost completely inhibited the SR Ca2+ uptake. EC50 of methyl methacrylate in percent inhibition of SR Ca2+ uptake was 16.1, 31.9, and 53.4 mM at pCa 7.0, 6.6, and 6.0, respectively. At low Ca2+ concentrations (0.1–1 μM), SR vesicles treated with 20 mM methyl methacrylate showed the decreased Ca2+ uptake rates. However, further increase of Ca2+ concentration to pCa 5.5 abolished the inhibitory effect of methyl methacrylate on SR Ca2+ uptake, showing no difference between the control and the methyl methacrylate-treated SR vesicles. From these results we could conclude that methyl methacrylate exerts a direct inhibition of cardiac SR Ca2+ uptake. This mechanism, at least in part, might contribute to the profound hypotension induced by methyl methacrylate. Supplementation of calcium ion appears to reduce the methyl methacrylate-induced cardiovascular disturbances efficiently. [Copyright &y& Elsevier]

Nickel sulfate supported on γ-Al2O3 was found to be very active even at room temperature, giving a maximum in both activity and acidity when catalyst containing 20% NiSO4 was calcined and evacuated at 600°C. The high catalytic activity of NiSO4/γ-Al2O3 was related to the increase of acidity and acid strength due to the addition of NiSO4. The asymmetric stretching frequency of the S&z.dbnd;O bonds for NiSO4/γ-Al2O3 samples was related to the acidic properties and catalytic activity. The active sites responsible for ethylene dimerization consist of a low-valent nickel, Ni+, and an acid, as evidenced by the IR spectra of CO adsorbed on NiSO4/γ-Al2O3 and Ni 2P XPS. [Copyright &y& Elsevier]

Highlights: [•] 3D collagen hydrogel provides effective culture environments for umbilical cord blood (UCB) derived cells [•] Hydrogel matrix stimulates UCB-derived cells to express neurotrophic factors [•] Neurotrophic factor release affects neurite outgrowth of neural precursor cells [•] Stem cell culture with 3D matrix is effective for neural regenerative therapy [ABSTRACT FROM AUTHOR]

Abstract: Clusterin is a stress-response protein that is involved in diverse biological processes, including cell proliferation, apoptosis, tissue differentiation, inflammation, and lipid transport. Its expression is upregulated in a broad spectrum of diverse pathological states. Clusterin was recently reported to be associated with diabetes, metabolic syndrome, and their sequelae. However, the regulation of clusterin expression by metabolic signals was not addressed. In this study we evaluated the effects of glucose on hepatic clusterin expression. Interestingly, high glucose concentrations significantly increased clusterin expression in primary hepatocytes and hepatoma cell lines, but the conventional promoter region of the clusterin gene did not respond to glucose stimulation. In contrast, the first intronic region was transcriptionally activated by high glucose concentrations. We then defined a glucose response element (GlRE) of the clusterin gene, showing that it consists of two E-box motifs separated by five nucleotides and resembles carbohydrate response element (ChoRE). Unexpectedly, however, these E-box motifs were not activated by ChoRE binding protein (ChREBP), but were activated by sterol regulatory element binding protein-1c (SREBP-1c). Furthermore, we found that glucose induced recruitment of SREBP-1c to the E-box of the clusterin gene intronic region. Taken together, these results suggest that clusterin expression is increased by glucose stimulation, and SREBP-1c plays a crucial role in the metabolic regulation of clusterin. [Copyright &y& Elsevier]