Mesenchymal stem cells (MSCs) can differentiate into chondroblasts, adipocytes, or osteoblasts under appropriate stimulation. Ghrelin, an endogenous ligand for the growth hormone secretagogue receptor (GHSR), stimulates growth hormone (GH) secretion, and has both orexigenic and adipogenic effects. This study sought to understand the potential involvement of members of MAPK serine/threonine kinases in the ghrelin-induced growth of rabbit MSCs ( rBMSC). We applied various concentrations of ghrelin to cultured rBMSC and observed the growth rate of the cells by MTT, changes in the phosphorylation state of ERK1/2, JNK and p38, and the expression levels of ALP, Runx2, and Osterix by wetern blot. We found that the growth and osteogenic differentiation of ghrelin-treated rBMSC are promoted primarily by phosphorylated ERK1/2, and that this phosphorylation, as well p38 phosphorylation, is mediated by GHSR. Our study suggests that ghrelin promotes the growth and osteogenic differentiation of rBMSC primarily through the ERK1/2 pathway.

The polygonal scaled boundary finite element method (PSBFEM) is a novel approach integrating the standard scaled boundary finite element method and the polygonal mesh technique. In this work, a user‐defined element (UEL) for dynamic analysis based on the PSBFEM is developed in the general finite element software ABAQUS. We present the main procedures of interacting with Abaqus, updating AMATRX and RHS, defining the UEL element, and solving the stiffness and mass matrices through eigenvalue decomposition. Several benchmark problems of free and forced vibration are solved to validate the proposed implementation. The results show that the PSBFEM is more accurate than the FEM with mesh refinement. Moreover, the PSBFEM avoids the occurrence of hanging nodes by constructing a polygonal mesh. Thus, the PSBFEM can choose an appropriate mesh resolution for different structures ensuring accuracy and reducing calculation costs.

To explore the clinicopathological characteristics and prognosis of idiopathic membranous nephropathy (IMN) with focal segmental sclerosis lesions (FSL). A total of 70 IMN patients with FSL (FSL+group) were enrolled in this study, and 140 patients were randomly selected by age and sex matching as disease controls (FSL-group). The clinical and renal histopathological data on renal biopsy and clinical data of patients regularly followed were collected. Serum anti-phospholipase A2 receptor (PLA2R) autoantibody, thrombospondin type-1 domain-containing 7A (7A) autoantibody, glomerular PLA2R and 7A expression, and IgG4 deposition were detected. First, the clinical and pathological significance of IMN combined with the FSL group was analyzed. Whether FSL is a risk factor for renal outcomes was further analyzed. 1. Compared with the FSL- group, patients in the FSL+ group had a significantly higher incidence of hypertension and a longer duration of hypertension as well as higher levels of systolic blood pressure, serum creatinine, serum triglycerides, serum cholesterol, 24-hour urinary protein excretion, and lower eGFR and urine osmotic pressure. Patients in the FSL+ group had an increased frequency of Churg stage III and more severe glomerulosclerosis and interstitial fibrosis. The remission rate was significantly lower in the FSL+ group than in the FSL- group (50.0% vs 75.9%, P = .027). 2. Multivariate Cox regression analysis showed that FSL (HR = 3.01, 95%CI = 1.07–8.52, P = .038) was an independent risk factor for progression of renal function deterioration, and FSL (HR = 3.25, 95%CI = 1.43–7.38, P = .005) and high levels of serum anti-PLA2R antibody (HR = 1.89, 95%CI = 1.27–2.82, P = .002) were independent risk factors for nonremission of IMN. IMN patients who developed FSL had more severe clinical and pathological characteristics than those without FSL. FSL was an independent risk factor for poorer prognosis. When the appearance of FSL in IMN patients with a high level of serum anti-PLA2R antibody, the treatment needs to be more aggressive to promote remission and to delay the progression of renal function.