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The urease membrane was immobilized on the surface of indium gallium zinc oxide (IGZO) based on polyethylene terephthalate substrate, which was used to develop an arrayed flexible urea biosensor in this study. In order to improve the properties of arrayed flexible IGZO/Al urea biosensor, graphene oxide (GO) was employed to modify the properties of arrayed flexible IGZO urea biosensor. Compared with the average sensitivity of 1.53 mV/(mg/dl) and linearity of 0.931 for arrayed flexible IGZO/Al urea biosensor, the average sensitivity and linearity of arrayed flexible IGZO urea biosensor modified by GO achieved 3.06 mV/(mg/dl) and 0.970, respectively. As the result, 5 mM pH 7.0 PBS buffer solution was the optimal measurement environment for Urease/IGZO/GO/Al urea biosensor, and which the average sensitivity was 3.65 [mV/(mg/dl)]. Anti-interference testing showed the arrayed flexible IGZO/Al urea biosensor modified by GO was not easily interfered from the other materials.

Fibroblast-like synoviocytes (FLSs) in rheumatoid arthritis (RA) present proliferative and aggressive cell phenotype. RA-FLSs are the essential effector cells that lead to symptoms like synovial inflammation and joint destruction. Currently, the cause of RA-FLSs involving in the pathological process of RA remains unknown. Accumulate researches have demonstrated that lncRNAs may play a critical role in regulating the biological behaviors of RA-FLSs, but the mechanism is still unclear. Here, we found that lncRNA small nucleolar RNA host gene 1 (SNHG1) is up-regulated in RA-FLSs compared with FLSs from trauma arthritis and osteoarthritis patients. The results suggest that SNHG1 in RA-FLSs helps to sustain the cellular functions of proliferation, migration and invasion. Furthermore, the regulation mechanism depends on the interaction between SNHG1 and polypyridine tract-binding protein 1 (PTBP1). This interaction influences PTBP1 expression that participates in the regulation of RA-FLSs biological behaviors. Our results suggest that up-regulated SNHG1 of RA-FLSs may contribute to synovial aggression and disease progression in RA and be favourable for RA treatment target RA-FLSs.

Fibroblast-like synoviocytes (FLSs) are the major effector cells that lead to rheumatoid arthritis (RA) synovitis and joint destruction. Our previous studies showed that Sonic Hedgehog (SHH) signaling pathway is involved in aberrant activation of RA-FLSs and inhibition of SHH pathway decreases proliferation and migration of RA-FLSs. The objective of this study was to investigate if the SHH pathway mediates proliferation and migration of RA-FLSs via the mitogen-activated protein kinases/extracellular signal-regulated kinases (MAPK/ERK) signaling pathway. SHH signaling was studied by using SHH agonist (Purmorphamine) and antagonist (Cyclopamine) targeting the Smoothened (SMO) in FLSs. U0126-EtOH was used to inhibit the MAPK/ERK signaling pathway. The phosphorylation of ERK 1/2 (p-ERKl/2) was examined by western blot. Cell viability was detected using cell proliferation and cytotoxicity kit-8 (CCK8), and cell cycle distribution and proliferating cells were evaluated by the flow cytometry. Cell migration was examined by Transwell assay. Results showed that, compared with the control group, Purmorphamine increased the levels of p-ERK1/2 in concentration-and time-dependent manners (P < 0.01). Co-treated with Purmorphamine and U0126-EtOH or Cyclopamine both decreased the levels of p-ERK1/2 (P < 0.05). RA-FLSs treated with Purmorphamine resulted in alteration of cell cycle distribution, increasing of proliferating cells, cell viability, and migration cells compared to controls (P < 0.01). However, the above phenomenon can be abolished by U0126-EtOH (P < 0.05). The findings suggest that SHH signaling pathway mediates proliferation and migration of RA-FLSs via MAPK/ERK pathway and may contribute to progression of RA. Targeting SHH signaling may have a therapeutic potential in patients with RA.

Aldosterone secretion is subjected to dopaminergic regulation. Our previous study showed that both human D2 and D4 dopamine receptors (D2R and D4R) modulate aldosterone secretion, but in opposing directions. The inhibitory effect of D2R is mediated by attenuating protein kinase C-μ (PKC-μ) and calcium-dependent signaling. The mechanism of D4R effect on angiotensin II (AII)-stimulated aldosterone secretion is explored in this study. Experiments were done with primary human adrenal cortical cells and human adrenocarcinoma (NCI-H295R) cells. Activation of different PKC isoforms was detected by specific phospho-PKC antibodies and PKC translocation. The role of calcium-dependent signaling was examined by measuring the cytoplasmic inositol 1,4,5-triphosphate (IP3) and calcium ([Ca2+]i). The D4R agonist PD-168,077 enhanced AII-stimulated aldosterone synthesis and secretion as early as 30 min following exposure independently of the modulation of aldosterone synthase (CYP11B2) transcription. CYP11B2 mRNA level elevated by AII was augmented by D4R in the later period. These effects were reversed by the D4R antagonist L-745,870. AII activated PKC-α/βII, -ε, and -μ but not PKC-δ, -θ, or -ζ/λ of H295R cells. The D4R agonist selectively enhanced AII-stimulated PKC-ε phosphorylation and its translocation to the cell membrane. Furthermore, the D4R agonist enhanced the AII-stimulated elevation of intracellular IP3 and [Ca2+]i. Inhibition of PKC-ε translocation by the PKC-ε-specific inhibitory peptide attenuated AII-stimulated aldosterone secretion, CYP11B2 mRNA expression, and elevation of intracellular IP3 and [Ca2+]i. We conclude that D4R augmented aldosterone synthesis/secretion induced by AII. The mechanisms responsible for this augmentation are mediated through enhancing PKC-ε phosphorylation and [Ca2+]i elevation.

The mechanism associated with the overproduction of aldosterone by aldosterone-producing adenomas (APA) is unknown.The objective of the study was to explore the role of the D2 dopamine receptor (D2R) on aldosterone synthesis and secretion and clarify the clinical importance of this role on aldosterone overproduction in APA.D2R expression in APA was examined in 24 patients and was much less than that in the nontumorous adrenal cortex. D2R mRNA levels in APA were inversely correlated with CYP11B2 mRNA levels and the patient's plasma aldosterone concentration. Angiotensin II (AII)-stimulated aldosterone secretion and CYP11B2 mRNA expression in human adenocarcinoma cells (H295R) was attenuated by the D2 agonist, bromocriptine (BMC). BMC selectively attenuated AII-induced protein kinase C (PKC)-mu phosphorylation and its translocation to the cell membrane. PKCmu-specific short-hairpin RNA significantly decreased AII-induced CYP11B2 mRNA expression and aldosterone secretion. BMC also attenuated the AII-induced increase in cytoplasmic calcium, partially through an inhibition of cytoplasmic inositol 1,4,5 triphosphate production. Despite similar total PKCmu levels in APA and the nontumorous adrenal cortex, expression of phosphorylated PKCmu in APA was much higher.This is the first study to demonstrate that the D2R modulated aldosterone secretion and synthesis through a specific attenuation of PKCmu activity, as well as the intracellular calcium level. Down-regulation of the D2R in APA, in turn, increased PKCmu activity and led to overproduction of aldosterone in affected patients. The D2R may thus serve as a potential treatment target for primary aldosteronism.

Dyschromatosis symmetrica hereditaria (DSH) is a rare autosomal dominant cutaneous disorder characterized by a mixture of hyperpigmented and hypopigmented macules of various sizes on the extremities. Pathogenic mutations in the DSRAD gene have been identified. In this report, we identified a Chinese family with a three-generation pedigree of DSH, in which a novel heterozygous nucleotide G--A transition was found. It is at position 3,125 in exon 12 of the DSRAD gene which induces a R1042H change in the putative deaminase domain of DSRAD. Our study expands the database on the DSRAD gene mutations in DSH.

Studies have shown that microRNA-148a (miR-148a) was proved to be silenced while DNA methyltransferase 1 (DNMT1) was over-expressed in gastric cancer. But the mechanism of aberrant expression of miR-148a and DNMT1 and their relationships in gastric cancer are still unknown. The aims of this study were to investigate the expression profile of miR-148a and DNMT1 and reveal whether they have any relationships. We used reverse-transcriptase quantitative real-time PCR, methylation-specific PCR and Western blot to measure the level of miR-148a expression, DNA methylation level and DNMT1 expression, respectively. Gastric cancer cells were transfected with plasmid or siRNA or treated with 5-aza-2'-deoxycytidine. Cell proliferation and apoptosis were detected by cell counting and flow cytometric analysis. In this study, we demonstrated that gastric cancer tissues and cell lines displayed a consistent down-regulation of miR-148a and hypermethylation of promoter region. DNMT1 was over-expressed in primary tumors and cell lines, while knockdown of DNMT1 using siRNA could decrease methylation level of miR-148a promoter and restore its expression. Furthermore, ectopic over-expression of miR-148a in cancer cell lines caused reduction in DNMT1 expression and inhibited cell proliferation, but no obvious change was found in apoptosis rate. These results suggest that miR-148a is inactivated by DNA hypermethylation of promoter region in gastric cancer, which is mediated through DNMT1 over-expression. Additionally, the silence of miR-148a reduces its suppression to DNMT1 in gastric cancer, and this may in turn result in over-expression of DNMT1 and promote DNA hypermethylation.