Conditioned medium from human dental pulp stem cells treats spinal cord injury by inhibiting microglial pyroptosis

Human dental pulp stem cell transplantation has been shown to be an effective therapeutic strategy for spinal cord injury.However,whether the human dental pulp stem cell secretome can contribute to functional recovery after spinal cord injury remains unclear.In the present study,we established a rat model of spinal cord injury based on impact injury from a dropped weight and then intraperitoneally injected the rats with conditioned medium from human dental pulp stem cells.We found that the conditioned medium effectively promoted the recovery of sensory and motor functions in rats with spinal cord injury,decreased expression of the microglial pyroptosis markers NLRP3,GSDMD,caspase-1,and interleukin-1β,promoted axonal and myelin regeneration,and inhibited the formation of glial scars.In addition,in a lipopolysaccharide-induced BV2 microglia model,conditioned medium from human dental pulp stem cells protected cells from pyroptosis by inhibiting the NLRP3/caspase-1/interleukin-1βpathway.These results indicate that conditioned medium from human dental pulp stem cells can reduce microglial pyroptosis by inhibiting the NLRP3/caspase-1/interleukin-1βpathway,thereby promoting the recovery of neurological function after spinal cord injury.Therefore,conditioned medium from human dental pulp stem cells may become an alternative therapy for spinal cord injury.

Enhancing Erectile Function and Alleviating Andropause Symptoms: Clinical Efficacy of a Human Stem Cell Conditioned Medium Cream

Erectile dysfunction (ED) is increasingly prevalent in Japan, exceeding 30%, and increasing with age. Unhealthy lifestyle habits, obesity, insufficient exercise, and smoking have been implicated in its pathogenesis, along with endothelial dysfunction of the corpora cavernosa and impaired blood flow to the penis considered underlying factors. However, the current treatments are limited to Phosphodiesterase-5 (PDE5) inhibitors. ED is the primary symptom of andropathy. This study reports the clinical efficacy of human stem cell-conditioned medium cream for ED treatment. Ten men without underlying diseases suspected of andropause with ED (mean age 43.2 ± 4.4 y, Hb 15.2 ± 0.6 gm/dL, AST/ALT 30.2/37.9 ± 12.4/14.0, eGFR 82.7 ± 12.4 mL/min/1.73 m2) were targeted. The cream was applied twice daily to the genital and scrotal areas. The erectile hardness score (EHS), International Index of Erectile Function-5 (IIEF-5), and Aging Male Symptoms (AMS) scale were used to evaluate the participants before and 30 days after use, and the results were compared using paired t-tests. The post-use qualitative opinions were collected through interviews. Significant improvements were observed compared to baseline in the IIEF-5 (11.8 ± 4.6→17.2 ± 5.1, P < 0.001), and AMS (46.3 ± 6.7→37.6 ± 5.3, P < 0.001) scores post cream use. EHS did not show a statistically significant difference, but a trend towards improvement was observed. Qualitative feedback included increased morning erection, improved maintenance of erection during intercourse, and reduced post work fatigue. Human stem cell-conditioned medium contains endothelial growth factors that potentially contribute to the improvement of ED and andropause by enhancing corporal endothelial function. Future studies should include control groups to further investigate the efficacy of these treatments.

Neural stem cell-conditioned medium upregulated the PCMT1 expression and inhibited the phosphorylation of MST1 in SHSY5Y cells induced by Aβ_(25-35)

A progressive neurodegenerative disease,Alzheimer’s disease(AD).Studies suggest that highly expressed protein isoaspartate methyltransferase 1(PCMT1)in brain tissue.In the current study,we explored the effects of neural stem cell-conditioned medium(NSC-CDM)on the PCMT1/MST1 pathway to alleviate Aβ_(25-35)-induced damage in SH-SY5Y cells.Our data suggested that Aβ_(25-35) markedly inhibited cell viability.NSC-CDM or Neural stem cell-complete medium(NSC-CPM)had a suppression effect on toxicity when treatment with Aβ_(25-35),with a greater effect observed with NSC-CDM.Aβ_(25-35)+NSC-CDM group exhibited an increase in PCMT1 expression.sh-PCMT1 markedly decreased cell proliferation and suppressed the protective role of NSC-CDM through the induction of apoptosis and improved p-MST1 expression.Overexpression of PCMT1 reversed the Aβ_(25-35)-induced decrease in cell proliferation and apoptosis.In summary,our findings suggest that NSC-CDM corrects the Aβ_(25-35)-induced damage to cells by improving PCMT1 expressions,which in turn reduces phosphorylation of MST1.

Extraction, Purification and Identification of Bone Morphogenetic Protein in Conditioned Medium of Osteosarcoma Cell (MG-63)

Objective: To find out a method of extraction and purification of bone morphogenetic protein (BMP) from osteosarcoma cell conditioned medium, and evaluate the biological activity of BMP.Methods: Conditioned medium of osteosarcoma cell lines (MG-63) was collected, concentrated and dialyzed. The concentrated protein was purified through gel chromatography on Sephcryl-S-100. The purified protein was tested by BMP monoclonal antibody (McAb), its molecular weight (MW) was determined by SDS-PAGE and its biological activity was demonstrated by heterotopic ossification.Results: The purified protein was proved to be BMP by BMP McAb, had a satisfactory heterotopic ossification, and its MW was about 21 kD.Conclusion: BMP existed in the conditioned medium of osteosarcoma cell and had a satisfactory biological activity after purification. Because osteosarcoma cell can be cultured and grew for a long timein vitro, this method will be helpful to a vast extraction of BMP and clinical application. Key words osteosarcoma cell - conditioned medium - bone morphogenetic protein - protein purification This project was a key scientific and technological program of Hubei Provicial Scientific and Technological Committee (No. 002p1503).

Endothelial progenitor cell-conditioned medium promotes angiogenesis and is neuroprotective after spinal cord injury

Endothelial progenitor cells secrete a variety of growth factors that inhibit inflammation, promote angiogenesis and exert neuroprotective effects. Therefore, in this study, we investigated whether endothelial progenitor cell-conditioned medium might have therapeutic effectiveness for the treatment of spinal cord injury using both in vitro and in vivo experiments. After primary culture of bone marrow-derived macrophages, lipopolysaccharide stimulation was used to classically activate macrophages to their proinflammatory phenotype. These cells were then treated with endothelial progenitor cell-conditioned medium or control medium. Polymerase chain reaction was used to determine mR NA expression levels of related inflammatory factors. Afterwards, primary cultures of rat spinal cord neuronal cells were prepared and treated with H2O2and either endothelial progenitor cell-conditioned medium or control medium. Hoechst 33258 and propidium iodide staining were used to calculate the proportion of neurons undergoing apoptosis. Aortic ring assay was performed to assess the effect of endothelial progenitor cell-conditioned medium on angiogenesis. Compared with control medium, endothelial progenitor cell-conditioned medium mitigated the macrophage inflammatory response at the spinal cord injury site, suppressed apoptosis, and promoted angiogenesis. Next, we used a rat model of spinal cord injury to examine the effects of the endothelial progenitor cell-conditioned medium in vivo. The rats were randomly administered intraperitoneal injection of PBS, control medium or endothelial progenitor cell-conditioned medium, once a day, for 6 consecutive weeks. Immunohistochemistry was used to observe neuronal morphology. Terminal deoxynucleotidyl transferase-mediated d UTP nick-end labeling assay was performed to detect the proportion of apoptotic neurons in the gray matter. The Basso, Beattie and Bresnahan Locomotor Rating Scale was used to evaluate the recovery of motor function of the bilateral hind limbs after spinal cord injury. Compared with the other two groups, the number of axons was increased, cavities in the spinal cord were decreased, the proportion of apoptotic neurons in the gray matter was reduced, and the Basso, Beattie and Bresnahan score was higher in the endothelial progenitor cell-conditioned medium group. Taken together, the in vivo and in vitro results suggest that endothelial progenitor cell-conditioned medium suppresses inflammation, promotes angiogenesis, provides neuroprotection, and promotes functional recovery after spinal cord injury.

Effects of feeder layer and BRL conditioned medium on mouse embryonic stem cells

In vitro growth and maintenance of embryonic stem (ES) cell lines derived from ICM cells of various blastocysts of 129 strain mice, the sustenance of their pluripotency and normal karyotype depend on the feeder layer of mouse embryonic fibroblasts (MEF). Compared with the feeder layer of MEF cells, medium conditioned by Buffalo rat liver cells (BRL-CM) is able to maintain pluripotency and karyo-typic normality of ES cells only in short term cell propagation. Besides, ES cells grown in BRL-CM are also capable of aggregation with 8-cell embryos of Swiss strain and develop into germ line chimaeras. Modification to the method of aggregating ES cells with early embryos by making a hole in agar layer on the top of MEF feeder cells was shown to be more convenient and efficient than the conventional microdrop method.

Effects of coriaria lactone-activated,astrocyte-conditioned medium on estrogen receptor and progesterone receptor expression in rat cortical and hippocampal neurons

BACKGROUND： Coriaria lactone-activated astrocytes released bioactive substances that eventually caused epilepsy. OBJECTIVE： It has been suggested that activated astrocytes alter the expression of the estrogen receptor and progesterone receptor by releasing bioactive substances during epilepsy, thereby affecting neuronal activity in the brain. This study was designed to observe the expression of the estrogen receptor and the progesterone receptor in rat brain following lateral ventricle injection of coriaria lactone-activated, astrocyte-conditioned medium. DESIGN AND SETTING： This immunohistochemical, randomized, controlled, animal study was conducted at the Department of Pathology, Hospital Affiliated to Binzhou Medical College, China. MATERIAL： Coriaria lactone was provided by Huaxi Pharmaceutical Factory, China. METHODS： Forty adult, healthy, male, Sprague Dawley rats were randomly assigned into two groups. Astrocyte-conditioned medium （10 μ L） was injected into rat lateral ventricle in the control group （n = 8）. Coriaria lactone-activated, astrocyte-conditioned medium （10 μL） was infused into the rat lateral ventricle in the coriaria lactone group （n = 32）. At 2, 4, 8 and 12 hours following injection, rats were sacrificed and subjected to immunohistochemistry. Eight rats were studied at each time point. MAIN OUTCOME MEASURES： Behavioral changes were observed in rats of both groups. Expression of the estrogen receptor and the progesterone receptor in rat cortical and hippocampal neurons was measured using immunohistochemistry. RESULTS： Four hours after injection, estrogen receptor levels in rat cortical and hippocampal neurons were significantly higher in the coriaria lactone group than in the control group （P 〈 0.05）. Progesterone receptor levels were significantly lower in the coriaria lactone group than in the control group （P 〈 0.05）. Seizures were not observed in the control group. In the coriaria lactone group, convulsions appeared 30 minutes after injection; seizures reached grade Ⅲ at 45 minutes rat behavior was nearly normal at 2 hours. CONCLUSION： Activated astrocytes can induce seizures in the rat by enhancing estrogen receptor expression and decreasing progesterone receptor expression in cerebral cortical and hippocampal neurons.

Effect of conditioned medium from neural stem cells on glioma progression and its protein expression profile analysis

BACKGROUND Emerging evidence suggests that the spread of glioma to the subventricular zone(SVZ)is closely related to glioma recurrence and patient survival.Neural stem cells(NSCs)are the main cell type in the SVZ region and exhibit tumor-homing ability.AIM To evaluate the effects of conditioned medium(CM)derived from SVZ NSCs on the cancer-related behaviors of glioma cells.METHODS The characteristics of SVZ hNSCs were identified by immunofluorescence.The normoxic-hNSC-CM and hypoxic-hNSC-CM(3%O2,oxygen-glucose deprived[OGD]culturing)were collected from 80%-90%confluent SVZ NSCs in sterile conditions.The CCK8 and Transwell assays were used to compare and evaluate the effects of normoxic-CM and hypoxic-CM on glioma proliferation and invasion.Then proteins secreted from SVZ NSCs into the CM were investigated by mass spectrometry,and the potential effects of candidate protein NCAN in the regulation of glioma progression were examined by CCK8 and Transwell assays.RESULTS The CM from SVZ NSCs significantly increased the proliferation and invasion of glioma cells,particularly the CM from OGD NSCs induced under hypoxic conditions.Furthermore,the secreted protein neurocan(NCAN)in CM from OGD NSCs was identified by proteomic analysis.NCAN was expressed in glioma cells and played regulatory roles in mediating the progression of glioma cells mainly via the Rho/Rho-associated protein kinase pathway.CONCLUSION Our study identified a potential interactive mechanism between SVZ NSCs and glioma cells,in which SVZ NSCs promote glioma progression via the secreted protein NCAN.These findings suggested that exploring the CM derived from cells could be a novel strategy for optimizing treatments and that NCAN derived from SVZ NSCs may be a potential new target in glioma progression.

Dental stem cell-conditioned medium for tissue regeneration: Optimization of production and storage

BACKGROUND Mesenchymal stem cells(MSC)effects on tissue regeneration are mainly mediated by their secreted substances(secretome),inducing their paracrine activity.This Conditioned medium(CM),including soluble factors(proteins,nucleic acids,lipids)and extracellular vesicles is emerging as a potential alternative to cell therapy.However,the manufacturing of CM suffers from variable procedures and protocols leading to varying results between studies.Besides,there is no welldefined optimized procedure targeting specific applications in regenerative medicine.AIM To focus on conditioned medium produced from dental MSC(DMSC-CM),we reviewed the current parameters and manufacturing protocols,in order to propose a standardization and optimization of these manufacturing procedures.METHODS We have selected all publications investigating the effects of dental MSC secretome in in vitro and in vivo models of tissue regeneration,in accordance with the PRISMA guidelines.RESULTS A total of 351 results were identified.And based on the inclusion criteria described above,118 unique articles were included in the systematic review.DMSC-CM production was considered at three stages:before CM recovery(cell sources for CM),during CM production(culture conditions)and after production(CM treatment).CONCLUSION No clear consensus could be recovered as evidence-based methods,but we were able to describe the most commonly used protocols:donors under 30 years of age,dental pulp stem cells and exfoliated deciduous tooth stem cells with cell passage between 1 and 5,at a confluence of 70%to 80%.CM were often collected during 48 h,and stored at-80°C.It is important to point out that the preconditioning environment had a significant impact on DMSCCM content and efficiency.

Intranasal Administration of Conditioned Medium from Cultured Mesenchymal Stem Cells Improves Cognitive Impairment in Olfactory Bulbectomized Mice

Alzheimer’s disease (AD) is the common cause of dementia which shows the neuro-pathologies like an accumulation of amyloid-β (Aβ) and degeneration of cholinergic neuron. Olfactory bulbectomized (OBX) mice show some of AD features, so they have been used to research as AD model. Mesenchymal stem cells (MSCs) can differentiate into many kinds of cells, including neuronal cells. In this study, we intranasally administrated the conditioned medium derived from cultured umbilical cord (UC) MSCs. The intranasal administration of the MSCs medium restored the cognitive impairment observed in OBX mice. In addition, the decreased number of choline acetyltransferase-positive cells in the medial septum was restored by the conditioned medium administration. In conclusion, MSCs-derived conditioned medium may have protective effects of cholinergic neurons in the medial septum, thereby rescuing the cognitive impairment of OBX.

Cycloheximide prevents production of arresting,a fraction of 30-50 kDa obtained from seminiferous tubule conditioned medium

Aim: To evaluate the effect of a protein synthesis inhibitor cycloheximide on arresting activity in spermato-genesis and sperm count in male rats. Methods: The study used seminiferous tubule (ST) segments from adult rats cultured in vitro with or without cycloheximide to condition culture media, which have been concentrated, size fractioned (30-50 kDa) and administered 7 days to adult rats by intraperitoneal injections. The effects on testicular and epididymal weights, spermatogenesis and epididymal sperm count were determined. Results: The fraction (30-50 kDa), named arresting, obtained from the culture without cycloheximide decreased testicular and epididymal weights (P<0.01) and reduced the epididymal sperm count significantly. Study of the spermatogenic cycle by transillumination showed spermatogenic arrest at stage VII in rats treated with arresting compared to that observed in controls. The length of stage VII in the group receiving the seminiferous tubules culture media with cycloheximide (30-50 KDa CHX-STCM fraction) was similar to control. Conclusion: The difference in the effect may be the result of the presence or absence of arresting, a protein secreted by the tubules.

Evaluation of the Secretome Profile and Functional Characteristics of Human Bone Marrow Mesenchymal Stromal Cells-Derived Conditioned Medium Suggest Potential for Skin Rejuvenation

Background/Purpose: Multipotent bone marrow-derived mesenchymal stromal cells (BMMSC) have been shown to possess the potential for tissue regeneration. The application of mesenchymal stromal cells (MSC)-derived growth factors and cytokines (GF/CKs) has been implicated for the repair and regeneration of the damaged skin that occurs due to aging and exposure to environmental stress factors. Methods: We have used both qualitative and quantitative measurements of the GF/CKs from the conditioned medium (CM) of a pooled population of BMMSC by antibody array analysis as well as by enzyme-linked immunosorbent assay (ELISA). Furthermore, the CM was also used in a variety of in vitro biological assays to measure its protective properties in human skin fibroblasts. Results: We have characterized the secretome of BMMSC by analyzing the composition of the CM using a forty-one growth factor array system. Thirteen of these GF/CK/extra cellular matrix (ECM)/ matrix metalloproteinases (MMP)-inhibitors in the CM were quantified owing to their involvement in skin repair cascade. In addition, we report that the BMMSC-CM was also able to protect dermal fibroblasts against tert-Butyl hydro peroxide (tbOH) induced oxidative stress and ultra violet B (UV-B) radiation induced cell damage. Conclusion: Based on the data presented here, we propose that BMMSC-derived CM may have the potential to promote health and rejuvenation of the aging skin.

CONDITIONED MEDIUM OF HUMAN NASOPHARYNGEAL CARCINOMA EPITHELIOID CELL LINE CNE_(1) CONTAINED THE ACTIVITIES OF TRANSFORMED GROWTH-INHIBITING FACTORS

The hormone defined serum free conditioned medium (SFCM) of human nasopharyngeal carcinoma epithelioid cell line (CNE1) was assayed by both the 3H-thymidine incorporation test and the soft agar test. It was found that the SFCM stimulated the growth of long-term serum-free cultured CNE4 cells in ac-cordence with the fact that the growth rate of long-term serum-free cultured CNE1 cells was directly proportional to the plating density. Alternatively 5% SFCM inhibited the growth of short-term serum-free cultured CNE4 cells by 51% in which the indicator cell remained the responsiveness state of growing in the serum-supplemented medium to the effector of interest. Furthermore, SFCM resulted in the inhibition of anchorage-independent growth of CNE4 cells and A431 cells. Also in soft agar test. SFCM reduced the colony formation of NRK(?),9F cells in the presence of EGF or EGF plus TGF-β. These finding suggested that CNE4 secreted autocrine growth stimulating factor(s) and growth inhibiting factor(s) in the serum-free medium, the latter strongly reverse malignant phenotypes of CNE4 and A431 cells in serum-supplemented surrounding.

The Skin Whitening Effect of Co-Cultured Conditioned Medium: Involvement of Synergy between Stem Cells and Immune Cells

Many researchers have described that mesenchymal stem cells conditioned medium and immune cells conditioned medium have a clear whitening effect when they are used as cosmetic ingredients. In this study, we confirmed the whitening efficacy of various concentrations of immune cells and stem cell conditioned media. The author tried to study a conditioned medium that has a strong whitening effect even with a composition of less than 20% (the most used concentration in cosmetics). Because of the fact that the conditioned medium contains various cytokines and growth factors secreted by stem cells or immune cells, it is known to have effects such as wound healing, antioxidant, and whitening effect. Recently, stem cells have been used not only in the development of cosmetic raw materials but also in skincare procedures, and there are reports being released of cosmetics using immune cells conditioned medium. The concentration-dependent whitening effect equivalently increased as the concentration of the mono-cultured conditioned medium was obtained through the stem cells or immune cells culture. In the case of co-culture, whitening results are like the effect of positive control such as arbutin in the medium carrying only 10% of the co-cultured conditioned medium. It is possible that enhanced whitening efficiency in co-cultured conditioned medium leads to a major innovation in the global cosmetic market.

miRNA-21-5p is an important contributor to the promotion of injured peripheral nerve regeneration using hypoxia-pretreated bone marrow-derived neural crest cells

Our previous study found that rat bone marrow–derived neural crest cells(acting as Schwann cell progenitors)have the potential to promote long-distance nerve repair.Cell-based therapy can enhance peripheral nerve repair and regeneration through paracrine bioactive factors and intercellular communication.Nevertheless,the complex contributions of various types of soluble cytokines and extracellular vesicle cargos to the secretome remain unclear.To investigate the role of the secretome and extracellular vesicles in repairing damaged peripheral nerves,we collected conditioned culture medium from hypoxia-pretreated neural crest cells,and found that it significantly promoted the repair of sensory neurons damaged by oxygen-glucose deprivation.The mRNA expression of trophic factors was highly expressed in hypoxia-pretreated neural crest cells.We performed RNA sequencing and bioinformatics analysis and found that miR-21-5p was enriched in hypoxia-pretreated extracellular vesicles of neural crest cells.Subsequently,to further clarify the role of hypoxia-pretreated neural crest cell extracellular vesicles rich in miR-21-5p in axonal growth and regeneration of sensory neurons,we used a microfluidic axonal dissociation model of sensory neurons in vitro,and found that hypoxia-pretreated neural crest cell extracellular vesicles promoted axonal growth and regeneration of sensory neurons,which was greatly dependent on loaded miR-21-5p.Finally,we constructed a miR-21-5p-loaded neural conduit to repair the sciatic nerve defect in rats and found that the motor and sensory functions of injured rat hind limb,as well as muscle tissue morphology of the hind limbs,were obviously restored.These findings suggest that hypoxia-pretreated neural crest extracellular vesicles are natural nanoparticles rich in miRNA-21-5p.miRNA-21-5p is one of the main contributors to promoting nerve regeneration by the neural crest cell secretome.This helps to explain the mechanism of action of the secretome and extracellular vesicles of neural crest cells in repairing damaged peripheral nerves,and also promotes the application of miR-21-5p in tissue engineering regeneration medicine.

烟碱降解细菌Ochrobactrum intermedium DN2生长培养基及培养条件的优化研究

在烟碱生物降解的研究和实际应用中,需要在较短的时间内获得大量O.intermediumDN2菌体。为了提高菌株DN2的菌体浓度,缩短其培养时间,本研究采用PlackettBurman设计对影响O.intermediumDN2生长的内在和外在相关因素进行了评价。结果表明,影响菌株DN2生长的显著因素有胰蛋白胨、MgSO4·7H2O、初始pH值、温度、装液量和培养时间。在此基础上,采用响应曲面法分别对该菌生长培养基的组成和培养条件进行优化,得到最佳培养基组成为(g/L):胰蛋白胨11.34、牛肉膏3.00、NaCl5.00、MgSO4·7H2O3.71,pH值7.23;最佳培养条件为温度32℃、转速120r/min、装液量88ml/250ml三角瓶、培养时间34h。5L发酵罐验证实验表明,菌株DN2达到最大生长量的时间为36h,与预测值34h基本一致,比优化前缩短约12h;最大菌体浓度为6.49×109cfu/ml,与预测值6.73×109cfu/ml接近,比优化前高近一个数量级。

乳酸干预破骨细胞条件培养基促进内皮细胞血管的生成

背景:聚乳酸作为可降解的骨组织工程支架材料被广泛用于组织再生与修复研究,在促进组织愈合与新骨形成、血管生成中具有重要作用。目的:观察聚乳酸降解终产物乳酸对破骨细胞的作用,以及乳酸干预后破骨细胞条件培养基对血管内皮细胞增殖、迁移和小管形成功能的影响。方法:(1)取对数生长期的小鼠单核巨噬细胞系RAW264.7,贴壁后分别加入含0,5,10,20 mmol/L乳酸的破骨诱导培养基(含核因子κB受体活化因子配体、体积分数10%胎牛血清的DMEM培养基),培养5 d后分别进行抗酒石酸酸性磷酸酶与细胞骨架纤维状肌动蛋白染色,培养24h后采用RT-PCR检测抗酒石酸酸性磷酸酶5 m RNA表达。(2)取对数生长期的RAW264.7细胞,贴壁后分2组培养:对照组加入破骨诱导培养基,实验组加入含10 mmol/L乳酸的破骨诱导培养基,培养5 d后更换为无血清DMEM培养基继续培养24 h,离心取上清液,分别与等体积含体积分数10%胎牛血清DMEM培养基混合后作用条件培养基备用。取对数生长期的人脐静脉内皮细胞,分别与对照组、实验组条件培养基共培养,通过CCK-8、Transwell、划痕、成管实验观察细胞的增殖、迁移和成管能力,通过RT-PCR和Western Blot检测血管生成相关基因和蛋白的表达。结果与结论:(1)抗酒石酸酸性磷酸酶与肌动蛋白染色结果显示,5,10 mmol/L乳酸可促进RAW264.7细胞破骨向分化,其中以10 mmol/L乳酸的促进作用更显著;RT-PCR检测结果显示,5,10,20 mmol/L乳酸均可提高酒石酸酸性磷酸酶5 m RNA的表达,其中以10 mmol/L乳酸的提高作用最显著;(2)与对照组条件培养基相比,实验组条件培养基可促进人脐静脉内皮细胞的增殖、迁移与成管能力(P<0.05),提高血管内皮生长因子、血管生成素1的m RNA和蛋白表达(P<0.05);(3)结果表明,乳酸诱导分化的破骨细胞条件培养基可促进内皮细胞的血管生成,机制可能与提高血管内皮生长因子、血管生成素1表达相关。

基于CMS的核电厂安全壳设计地震动确定方法

选取符合核电厂设计要求的输入地震动进行结构动力时程反应分析是保障核电厂抗震能力的重要环节。基于条件均值谱(CMS)的输入地震动选取方法具有既考虑结构自身动力特性又考虑场地地震危险性特征的优点,已经在地震工程相关领域得到应用。以核电厂安全壳结构为研究对象,从概率地震危险性分析出发,以条件均值谱为输入地震动目标谱,给出了核电厂安全壳输入地震动目标谱的计算流程;在国内外选取的18次典型地震的2 480条地震动数据库中,选取了与目标谱匹配良好的40条地震动;再利用epsilon方法在上述地震动数据库中各选取40条地震动,将这两组地震动分别输入安全壳有限元模型中进行动力时程分析,通过对比两种方法顶点的最大位移平均值与标准差,发现CMS方法选取的地震动记录无偏性最好,是一种高效合理的输入地震动选取方法。

如何选择风力发电机组的CMS系统

文章叙述了风电场风力发电机组CMS系统的基本功能和作用,介绍了目前CMS状态监测系统不同的分析方法以及差别。在文章中作者结合自己的工作经验和风力发电机组的特点,提出了风电场设备维修人员和振动故障诊断人员需要什么样的CMS系统。其目的是帮助用户正确选择合适的CMS系统。

ACM对tbOOH致原代神经细胞损伤及凋亡的影响

目的 探讨星形胶质细胞条件培养液 (ACM)对叔丁基脂氢过氧化物 (tb OOH)诱导的原代神经细胞损伤和凋亡的影响。方法 分离培养 SD大鼠大脑皮层星形胶质细胞和神经细胞 ,以 ACM和 /或 tb OOH处理神经细胞后 ,采用 MTT法和光镜评估细胞的生存力 ,Hoechst332 5法观察细胞凋亡 (率 )的变化 ;共聚焦显微镜检测细胞内 Bcl- 2表达。结果 与 tb OOH处理组相比 ,ACM可降低神经细胞损伤和凋亡 (P<0 .0 5) ,增加细胞内 Bcl- 2表达。结论 ACM有保护氧自由基 tb OOH诱导的神经细胞损伤和凋亡作用 ,Bcl- 2表达增加可能参与了 ACM的抑制凋亡。