Effects of Lanthanum on Bone Resorbing Activity of Rabbit Mature Osteoclasts Co-Cultured with Osteoblasts

The effects of lanthanum (Ⅲ) on the bone resorbing activity of rabbit mature osteoclasts (OCs) in the presence of osteoblasts (OBs) were studied in vitro by measuring the number and area of absorption pits. La(Ⅲ) at concentrations ranging from 1.00×10-5 to 1.00×10-8 mol·L-1 show no effect on mature OC number (P＞0.05). In the OC-OB co-culture systems without La(Ⅲ), osteoblasts alone did not influence the pit number and area whether the two kinds of cells were in contact or not (P＞0.05). Under the OC-OB not-in-contact condition, the effect of La(Ⅲ) on the bone-resorbing activity of OCs was similar to that of La(Ⅲ) in the absence of OBs (P＞0.05). However, while OCs were in direct contact with OBs, the inhibitory effects of La(Ⅲ) on OCs' bone-resorbing activity decreased at the concentrations of 1.00×10-5, 1.00×10-6 and 1.00×10-7 mol·L-1, and the promotion effects increased at 1.00×10-8 mol·L-1 (P＜0.05). The results suggest that direct cell-cell contact between OC and OB be essential for OBs to play their role in regulating the response of OCs to La(Ⅲ).     

Effects of Lanthanum on Formation and Bone-Resorbing Activity of Osteoclast-Like Cells

The effect of La3 on formation of osteoclast-like cells in rabbit bone marrow cells induced by 1,25-dihydroxyvitamin D3 and their bone-resorbing activity was evaluated by counting the number of tartrate resistant-acid phosphatase-positive ［TRAP( )］ multi-nucleated cells and measuring the number and surface area of bone resorption pits with photomicrography and image analysis. The formation and morphological characteristics of osteoclast-like cells and bone resorption pits were observed under a phase contrast inverted microscope. La3 promotes the formation of osteoclast-like cells at the concentration of 1.00×10-8mol·L-1 compared with the control group(P<0.01), whereas no significant change in cell number is observed at higher concentrations(1.00×10-5, 1.00×10-6 and 1.00×10-7 mol·L-1)(P>0.05). La3 at the concentration of 1.00×10-8mol·L-1 also increases the number and surface area of the resorption pits(P<0.01), but inhibits the bone-resorbing activity dose-dependently(P<0.01)at higher concentrations(1.00×10-5, 1.00×10-6 and 1.00×10-7 mol·L-1). These findings suggest that La3 may promote or inhibit the formation and bone-resorbing activity of osteoclast-like cells depending on its concentration.     

间充质干细胞源性外泌体及其在创面修复中的研究进展

外泌体（exosomes）是细胞分泌的膜性囊泡,其作为干细胞旁分泌因子参与了创面修复。该文对近年间充质干细胞外泌体促进创面修复的研究进展进行综述,外泌体通过调控炎症反应、促进细胞增殖及血管再生、调控细胞外基质重塑及抑制瘢痕形成等多种途径全面地参与了创面修复。工程化干细胞可提高其外泌体功效和产量,为外泌体临床应用带来了巨大的潜力和优势。     

P2混合动力汽车发动机起动过程变速箱控制策略研究

为实现P2混合动力汽车发动机起动过程整车驾驶的平顺性,对发动机起动过程变速箱的转矩预控控制策略进行了研究,针对现有控制策略在实车验证中存在的不足,提出了一种新的变速箱转矩预控控制策略.通过设计变速箱控制时的电机转速与DCT变速箱输入轴之间转速差的判断条件,避免了起动过程因转速波动而引起的整车顿挫,同时变速箱转矩控制过程...     

Ytterbium ion promotes apoptosis of primary mouse bone marrow stromal cells

One of the main target organs for the lanthanides(Ln) is bone. Previous studies revealed that ytterbium(Yb) produced damage to the skeletal system in vivo. But the effects of Yb3+ on bone marrow stromal cells(BMSCs) in vitro had not been reported. In this paper, cell viability, apoptosis, mitochondrial membrane potential(MMP), reactive oxygen species(ROS) and lactate dehydrogenase(LDH) were measured in order to study the effects of Yb3+ on BMSCs. The results indicated that Yb3+ displayed a slight positive effect on the BMSCs viability at concentrations of 1×10–6, 1×10–5, and 1×10–4 mol/L, but turned to decrease the viability of BMSCs at the highest concentration of 1×10–3 mol/L for 24, 48 and 72 h. Yb3+ at 1×10–3 mol/L promoted apoptosis of BMSCs, increased the levels of ROS and LDH, and decreased MMP in BMSCs. It suggested that the precipitate of Yb PO4 might decrease the viability of BMSCs. Yb3+ induced the apoptosis of BMSCs via mitochondrial pathway. The results might be useful for more rational application of Yb-based compounds in the future.     

Effect of Lanthanum（ Ⅲ ） on Cytosolic Free Calcium in Isolated Rabbit Mature Osteoclasts

Theformationandresorptionofboneismain tainedbytheinteractionsofosteoblasts(OBs)withos teoclasts(OCs),andafunctionalimbalancebetween themmaycausethelossofbonemass.OCsaremulti nucleatedcellsformedbythefusionofmononuclear progenitorsofthemonocyte macrophagef…     

Effects of gadolinium on proliferation, differentiation and calcification of primary mouse osteoblasts in vitro

To evaluate the effects of Gd on proliferation, differentiation and mineralization function of primary osteoblasts (OBs) in vitro, we tested cell viability by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay, cell differentiation by alkaline phosphatase (ALP) activity assay, synthesis of type ? collagen, and oil red O and alizarin red S (ARS) stain assays. The results indicated that effects of Gd on the proliferation, osteogenic differentiation, mineralization function and adipocytic transdifferentiation of primary OBs de-pended on concentration and incubation time, but were not dose-dependent. It was suggested that the effect of Gd on bone metabolism was complicated, and concentration and culture time were key factors for switching the biological effects of Gd from damage to protection.     

Effect of yttrium ion on the proliferation,differentiation and mineralization function of primary mouse osteoblasts in vitro

A series of experimental methods including MTT test,alkaline phosphatase(ALP) activity measurement,oil red O stain and measurement and mineralized function were employed to assess the effects of Y3+ on the proliferation,differentiation,adipogenic transdifferentiation and mineralization function of primary mouse osteoblasts(OBs) in vitro.The results indicated that Y3+(1×10-9,1×10-8,1×10-7,1×10-6,1×10-5,and 1×10-4 mol/L) promoted the proliferation of OBs on day 1,2 and 3.Y3+ had no effect on the differentiati...     

浅谈仪表自动化在化工工业方面的应用

自动化是我国化工工业生产中应用广泛的一种技术手段,通过相关设备,结合多种科技形式,自主管理工业生产的多个环节.我国的自动化技术随着科技发展而发展,目前,自动化设备的功能越来越完善,仪表精度越来越高,其智能化、集成化、自动化的程度也越来越好.基于此,本文就仪表自动化在化工工业方面的应用进行详细探究.     

油墨刮刀电刷镀层厚度与刷镀工艺参数关系的数学模型

油墨刮刀表面强化层的厚度是影响刮刀制作质量的重要因素,目前国内这方面的研究尚不深入。应用电刷镀方法对传统刮刀进行镀覆,分析了电刷镀工艺参数对油墨刮刀镀层厚度的影响。采用中心组合设计法和响应面法,建立了镀层厚度与刷镀电压及镀头运动速度之间的数学模型。结果表明:刷镀层厚度随电压的增大而增大,随镀头运动速度的增大而减小;在刷镀过程中可以根据该模型控制电压,动态优化镀头运动速度,实现镀层厚度的均匀化和精确控制。