[Bone marrow mesenchymal stem cells interactions with hepatocytes and hepatic stellate cells on different stiff substrates].

Objective: To explore the effect of substrate mechanical microenvironment and cell-cell interaction on differentiation of bone marrow mesenchymal stem cells (BMSCs), intrahepatic cellular function and phenotype. Methods: Bone marrow mesenchymal stem cells (BMSCs)-hepatocytes (HCs) and BMSCs-hepatic stellate cells (HSCs) were co-cultured on polyvinyl alcohol (PVA) hydrogel substrates at different stiffness (4.50 ± 0.47 kPa, 19.00 ± 3.51 kPa and 37.00 ± 2.09 kPa) by non-contact co-culture method. Furthermore, the effect of substrate mechanical microenvironment on BMSCs, HCs and HSCs and the activation and proliferation of HCs under different co-cultured condition was studied. A Student's t-test was used to compare the two groups. Results: The expression ofα-smooth muscle actin (α-SMA) and collagenα1- I (Col1A1) in BMSCs and HSCs cultured on its own increased with increase of substrate stiffness. After 72 h, the expression of albumin (ALB) of HCs on three stiff substrates was significantly higher than that of 24 and 48 h. Moreover, the expression of ALB of HCs increased with the increase of substrate stiffness. During the co-culture of BMSCs and HSCs, BMSCs of all three stiffness substrates promoted the expression ofα-SMA, Col1A1 in HSCs, but reduced the expression of PPARγin HSCs cells, thererby promoted the activation of HSCs, with apparent stiffness at 37 kPa. HSCs promoted the expression of ABL in BMSCs at three stiff substrates, but inhibited the expression of alpha-SMA and Col1A1 in BMSCs at 37 kPa, suggesting that co-culture had inhibited the differentiation of BMSCs myofibroblasts, and promoted the differentiation of hepatocyte-like cells, especially at high stiff substrates. In the co-culture of BMSCs and hepatic parenchymal cells, BMSCs had promoted the proliferation of hepatic parenchymal cells at 4.5 kPa. Further, hepatic parenchymal cells had inhibited the expression ofα-SMA in BMSCs, and promoted the expression of Alb, with inhibition of BMSCs differentiation towards myofibroblasts. Conclusion: The differentiation of BMSCs affects the substrate mechanical microenvironment, co-culture of HCs and HSCs. Simultaneously, affecting the function of hepatocytes in relation to the mechanical state of the substrates.

[Determination and significance of serum MPO and amylin in adult patients with OSAHS after short-range noninvasive positive pressure ventilation].

Objective:The aim of this study to investigate the determination and significance of serum MPO and amylin in adult patients with OSAHS after short-range noninvasive positive pressure ventilation. Method:Eighty-seven OSAHS patients were divided into severe group (30 cases), moderate group (30 cases) and mild group (27 cases) according to the AHI range. Twenty-seven outpatient health persons were selected as the control group. Serum amylin and myeloperoxidase were measured by ELISA; Amyloid and myeloperoxidase were reassessed in 30 patients with severe OSAHS after 6 months of combined therapy, and the relationship between amylin, myeloperoxidase and PSG was analyzed. Result:①With the severity of OSAHS patients increased, the serum amylin and myeloperoxidase levels gradually increased (F=22.486, 19.755;P<0.01); There was no significant difference in MPO and amylin concentration between the mild group and the control group (P>0.05), and the other groups were significantly different from each other (P<0.01). ②There was no correlation among serum amylin and myeloperoxidase level and BMI and age in OSAHS patients (P>0.05); and a negative correlation with SaO2, and AHI was positively correlated (P<0.01). ③After 3 months of CPAP treatment, LSaO2 increased which the AHI and peripheral blood MPO, amylin levels lower than before in 30 patients (P<0.05); The amylin and myeloperoxidase concentrations of blood after 6 months of treatment were significantly lower than those of 3 months after treatment (P<0.05), which still increased compared with the control group. Conclusion:The determination of serum amylin and MPO in patients with OSAHS has a certain reference value in predicting the condition and curative effect of diabetes mellitus and insulin resistance. CPAP treatment can significantly reduce the degree of hypoxiapatients and cardiovascular damage in OSAHS patients, which was significantly correlated with the treatment time.