Isolation and Culture of a kind of Derived Cells from Differentiation Group Of Murine ESC-like Cell and Their Traits in Culture

1 Introduction In the process of culturing ESC-like cell from murine blastula,we find that even if no inducing factor was added, ESC-like cell masses can different into many kinds of cell groups. Study on the biological traits, culturing and change of functional genetics of those cell groups will be of great meaning to find out the mechanism of differentiation and possible value of ESC-like cells. UP to now, there are not many references and reports on this aspect. This article introduces a kind of derived cells isolated from ESC-like cell, the change of its growth, and need of culturing conditions, which may be useful in further study on ESC-like cells.     

Biological characteristics and immunoregulation of exosomes derived from mesenchymal stem cells北大核心

BACKGROUND: Clarifying the synthesis and regulation of exosomes derived from mesenchymal stem cells is of great significance to the research and application of exosomes in the future. OBJECTIVE: To summarize the biological characteristics in exosomes derived from different mesenchymal stem cells and the role of these exosomes in the immune regulation, which hopes to find new breakthroughs in the study of exosomes in the future and provide ideas for cell-free therapy. METHODS: The articles were searched on PubMed, CNKI and Wanfang using the keywords of “stem cells, mesenchymal stem cells, exosomes, immunomodulation, inflammatory mediator, biological characteristics of exosomes, biological characteristics of mesenchymal stem cells, regeneration” in Chinese and English. Finally, 105 articles were included for review. RESULTS AND CONCLUSION: Mesenchymal stem cells are a type of pluripotent stem cells that exist widely in various tissues of the body. Mesenchymal stem cells not only have stem cell characteristics, but also play an important role in the immunosuppressive properties. Mesenchymal stem cells had been clinically applied for the treatment of many diseases. Therefore, mesenchymal stem cells were used to manage novel coronavirus pneumonia, and had ideal treatment effect. Exosomes are endosome-derived nanometer-scale vesicles (40–200 nm in diameter). Exosomes derived from mesenchymal stem cells have the same immune regulation function as its maternal cells, including that carrying immunosuppressive factors, promoting macrophages polarization into M2 type, preventing differentiation of pro-inflammatory T cell subsets and inhibiting antigen presentation. © 2022, Publishing House of Chinese Journal of Tissue Engineering Research. All rights reserved.     

Mechanobiology and Cartilage Tissue Engineering

1 IntroductionThe cartilage is a hydrated connective tissue in joints that withstands and distributes mechanical forces. Chondrocytes utilize mechanical signals to maintain tissue homeostasis. They regulate their metabolic activity through complex biological and biophysical interactions with the extracellular matrix (ECM). Although some of the mechanisms of mechanotransduction are known today, there are certainly many others left unrevealed. Different topics of chondrocytes mechanobiology ha…     

Biological Feature of Collagen-Chitosan Membrane with Basic Fibroblast Growth Factor for the Culture of Human Fibroblast

INTRODUCTION　　Collagen present in the extracellular matrix is the most promising natural poly-mer for tissue engineering.It has many expected biological features,includinggrowth promotion,biological stability,low antigenicity and cytotoxic properties.Collagen is frequently used material for cell culture carriers in various fields.Al-though collagen possess excellent biocompatibility,the chemical treatment makesthe reconstituted collagen very low tensile strength and easily biodegraded b…     

Application of graphene-based nanomaterials in stem cells北大核心

BACKGROUND: As a kind of newly-developing nanomaterial, graphene has been used in many fields. Many recent studies have found that graphene-based nanomaterials can affect the biological behaviors of stem cells. OBJECTIVE: To review the application and progress of graphene-based nanomaterials in stem cells. METHODS: We searched the articles about the application of graphene-based nanomaterials in stem cells published in PubMed, Web of Science, and CNKI databases with the search terms “graphene, nanomaterials, stem cell” in English and Chinese. Finally, 57 articles met the criteria for review. RESULTS AND CONCLUSION: Graphene-based nanomaterials have good stability and corrosion resistance, high mechanical strength, good biocompatibility, which are accepted as one of the most promising nanomaterials in biomedicine. Stem cells are undifferentiated cells that can differentiate into various mature cells in human body, which have a broad application prospect in tissue engineering, regenerative medicine and other fields. Many recent studies have applied graphene-based nanomaterials to stem cell research and found that they can affect the growth, proliferation, adhesion and differentiation of stem cells, and these nanomaterials may affect the biological behavior of stem cells by regulating the expression of related genes and various signaling pathways. However, graphene-based nanomaterials have biological toxicity, which restrict their application in biological aspects. Moreover, most researches only involved cellular level, and it needs further animal studies and in vivo experimental researches. © 2022, Publishing House of Chinese Journal of Tissue Engineering Research. All rights reserved.     

Expressions of Collagen I and III in Mesenchymal Stem Cells Co-cultured with Ligament Fibroblasts

1 IntroductionThe poor or failed healing of some tendons and ligaments leads to the requirement of surgical replacement of grafts. Tissue engineering offers the appealing potential to improve the reconstruction of tissues presenting acceptable biological and mechanical properties. Mesenchymal stem cells (MSCs) have been shown to differentiate into several cells. The implantation of MSCs into damaged rabbit Achilles tendons significantly improved the structural properties of the neo-tissues,…     

Mechanical Properties of Living Adherent Cells :Relationship with Structure and Function

1 IntroductionMechanical properties of living cells are dependent on a variety of intracellular and/or extracellular factors (e.g., spatial organization of cytoskeleton (CSK) elements; internal tension; actomyosin contraction; contribution of proximal and/or more distal environment...). Because these factors are involved in biological processes as important as cell adhesion, locomotion, cell contraction, signalization, understanding the relationships between cell mechanical properties, struct…     

炎症的自主神经调控与临床意义

Enormous progresses have been made in recent years for the involvement of nervous system in particular the vagus nerve in inflammatory responses. The parasympathetic nerve can be activated by “inflammatory reflex“ to inhibit macrophages, via their specific nicotinic receptor α- 7 subunit, and hence to reduce the production of tumor necrosis factor [TNF) that plays a pivotal role in many inflammatory reactions and is a key mediator for septic shock. This cholinergic anti - inflammatory pathway has been utilized, with positive outcomes, by means of either pharmacological or electrical stimulation in animal models against inflammatory responses and septic shock. Monoclonal antibodies against TNF and other pro- inflammatory cytokines have also been developed and used against inflammation experimentally and clinically. Although clinical use of these new treatments have yielded primitive and only limited results, these new research findings and concepts are important for the advance of modem medicine, as well as for better comprehension of some theories and practices in traditional medicine. Future directions are discussed herewith.     

Composite scaffolds for bone tissue engineering: Application review and future direction北大核心

BACKGROUND: In general, a single-type artificial bone is difficult to meet the requirements for bone defect repair and extracellular matrix of bone tissue engineering. Compositing and processing the materials with different properties can form the composite-type artificial bone, which can either ensure the biological activity or effectively improve its mechanical properties. OBJECTIVE: To summarize the present situation of the application of composite-type artificial bone and prospects the development trend. METHODS: The literatures were retrieved from CNKI, ScienceDirect, PubMed, SpingerLink, EI Village, Wiley databases from January 2000 to April 2017. The key words were “composite scaffold, tissue engineering, artificial bone” in Chinese and English, respectively. The selected literatures were analyzed according to the inclusion and exclusion criteria. RESULTS AND CONCLUSION: The requirements for the scaffolds used for bone tissue engineering are complex and it should carefully consider and control various factors used in the design and preparation of scaffolds, including microporous structure, mechanical strength, degradation rate, porosity, growth factor, morphology and surface chemistry, so as to meet the bone tissue engineering applications. The preparation of tissue-engineered bone scaffold is based on biological active substances and matrix materials through a reasonable manner. It simulates the components of natural bone matrix, promotes the adhesion, proliferation and differentiation of bioactive substances, and gives play to its functions of osteogenesis. Although existing techniques and methods have made significant progress in the preparation of composite scaffolds, there is no technique or method to fully meet all the requirements for preparation of tissue-engineered bone scaffold. © 2018, Journal of Clinical Rehabilitative Tissue Engineering Research. All rights reserved.     

瘦素（leptin）与肥胖

Obesity is a severely public health problem the whole society faces, and it is correlated closely with many diseases, such as diabetesⅡ, hypertension, coronary heart disease,gallqtone, and so on.Therefore it threatens people‘ s survival quality severely. Obesity is a multiple - factor disease including genetic, metabolic and behavioral factor, and the gene is the main determining factor. With the development of molecular biology technique, people have founded several genes involved in obesity. Among these genes, the research on obese gene is the most profound. The protein leptin is the expression product of the obese gene.This review elucidates the structure, the main biological function, the mechanism of leptin and it‘‘s relationship with obesity.     

Inhibition of HSP90 could be possible mechanism for anti-cancer property of amniotic membrane

Amniotic membrane (AM), the innermost layer of the fetal membrane, is considered as a suitable candidate for cancer therapy. In order to develop the AM as a new cancer therapeutic approach, it is essential to understand the molecular mechanism of the AM anti-cancer properties. Previous studies demonstrated that anti-proliferative effects of the AM on tumor cells were associated with induction of cell cycle arrest. Moreover, it has been shown that unknown substances in the AM induce apoptosis in cancer cells and inhibit angiogenesis in tumors. In contrast to the effects of the AM, heat shock proteins (HSPs), in particular HSP90, play a crucial role in development of tumorgenesis. HSP90 inhibits apoptosis in cancer cells and enhances angiogenesis and cell cycle progression. Based on the opposite effects of the amniotic membrane ingredients and HSP90, we hypothesized here that possible mechanism of the AM anti-cancer effects is through inhibition of HSP90.     

The use of trehalose-treated freeze-dried amniotic membrane for ocular surface reconstruction

The aim of this study was to evaluate the efficacy and safety of trehalose-treated freeze-dried amniotic membrane (TT-FDAM) for ocular surface reconstruction. Human AM deprived of amniotic epithelial cells was first incubated with 10% trehalose solution, and then freeze-dried, vacuum-packed, and sterilized with gamma-irradiation. The resultant newly developed TT-FDAM was characterized for its physical, biological, and morphological properties by comprehensive physical assays, immunohistochemistry, electron microscopy, cell adhesion assay, 3D cell culture, and an in vivo biocompatibility test. The adaptability of TT-FDAM was markedly improved as compared to FDAM. Immunohistochemistry for several extracellular matrix molecules revealed that the process of freeze-drying and irradiation apparently did not affect its biological properties, however, electron microscopy revealed that the detailed morphological appearance of TT-FDAM is more similar to that of native AM than to FDAM. Intracorneal and scleral-surface transplantation of TT-FDAM showed excellent biocompatibility with ocular surface tissues. Thus, TT-FDAM retained most of the physical, biological, and morphological characteristics of native AM, consequently it is a useful biomaterial for ocular surface reconstruction.     

Induction of Adrenomedullin mRNA and Protein by Lipopolysaccharide and Paclitaxel (Taxol) in Murine Macrophages

Lipopolysaccharide (LPS), a potent inflammatory stimulus derived from the outer membrane of gram-negative bacteria, has been implicated in septic shock. Plasma levels of adrenomedullin (AM), a potent vasorelaxant, are increased in septic shock and possibly contribute to the characteristic hypotension. As macrophages play a central role in the host response to LPS, we studied AM production by LPS-stimulated macrophages. When peritoneal exudate macrophages from C3H/OuJ mice were treated with protein-free LPS (100 ng/ml) or the LPS mimetic paclitaxel (Taxol; 35 μM), an ~10-fold increase in steady-state AM mRNA levels was observed, which peaked between 2 and 4 h. A three- to fourfold maximum increase in the levels of immunoreactive AM protein was detected after 6 to 8 h of stimulation. While LPS-hyporesponsive C3H/HeJ macrophages failed to respond to protein-free LPS with an increase in steady-state AM mRNA levels, increased levels were observed after stimulation of these cells with a protein-rich (butanol-extracted) LPS preparation. In addition, increased AM mRNA was observed following treatment of either C3H/OuJ or C3H/HeJ macrophages with soluble Toxoplasma gondii tachyzoite antigen or the synthetic flavone analog 5,6-dimethylxanthenone-4-acetic acid. Gamma interferon also stimulated C3H/OuJ macrophages to express increased AM mRNA levels yet was inhibitory in the presence of LPS or paclitaxel. In vivo, mice challenged intraperitoneally with 25 μg of LPS exhibited increased AM mRNA levels in the lungs, liver, and spleen; the greatest increase (>50-fold) was observed in the liver and lungs. Thus, AM is produced, by murine macrophages, and furthermore, LPS induces AM mRNA in vivo in a number of tissues. These data support a possible role for AM in the pathophysiology of sepsis and septic shock.     

Urocortin and adrenomedullin prevent lethal endotoxemia by down-regulating the inflammatory response

Urocortin 1 (UCN) and adrenomedullin (AM) are two neuropeptides that have emerged as potential endogenous anti-inflammatory factors based on their production by and binding to immune cells. Because human septic shock involves excessive inflammatory cytokine production, we investigated the effect of UCN and AM in the production of inflammatory mediators and their therapeutic actions in two models of septic shock. Both peptides down-regulated the production of inflammatory mediators by endotoxin-activated macrophages. The administration of UCN or AM protected against lethality after cecal ligation and puncture or after injection of bacterial endotoxin and prevented septic shock-associated histopathology, such as infiltration of inflammatory cells and intravascularly disseminated coagulation in various target organs. The therapeutic effect of UCN and AM was mediated by decreasing the local and systemic levels of a wide spectrum of inflammatory mediators, including cytokines, chemokines, and the acute phase protein serum amyloid A. Importantly, UCN or AM treatment was therapeutically effective in established endotoxemia. In conclusion, UCN and AM could represent two multistep therapeutic agents for human septic shock to be used in combination with other immunomodulatory agents or complementary as anti-inflammatory factors to other therapies.     

Computed tomography characterisation of additive manufacturing materials

Additive manufacturing, covering processes frequently referred to as rapid prototyping and rapid manufacturing, provides new opportunities in the manufacture of highly complex and custom-fitting medical devices and products. Whilst many medical applications of AM have been explored and physical properties of the resulting parts have been studied, the characterisation of AM materials in computed tomography has not been explored. The aim of this study was to determine the CT number of commonly used AM materials. There are many potential applications of the information resulting from this study in the design and manufacture of wearable medical devices, implants, prostheses and medical imaging test phantoms. A selection of 19 AM material samples were CT scanned and the resultant images analysed to ascertain the materials' CT number and appearance in the images. It was found that some AM materials have CT numbers very similar to human tissues, FDM, SLA and SLS produce samples that appear uniform on CT images and that 3D printed materials show a variation in internal structure.     

雌激素减轻失血性休克器官损伤的作用与机制

正战伤、交通事故伤、自然灾害和大手术等多种严重创伤因素引起机体大量失血,导致组织有效循环血量急剧减少,引起失血性休克,以急性循环障碍和组织严重缺氧为特征,以组织、细胞损伤和功能障碍为严重后果,是创伤患者死亡的重要原因之一~([1])。经过多年的研究实践,休克的防治取得了很大进步,但重症休克的病死率仍居高不下。据报道,2000~2010年间,创伤性损伤已成为美国46岁以下人口最主要的死亡原因,失血占各种创伤性致死病因的     

The central role of adrenomedullin in host defense

Thirteen years after the isolation of adrenomedullin (AM) from a human pheochromocytoma, the literature is awash with reports describing its implication in countless physiological and disease mechanisms ranging from vasodilatation to cancer promotion. A growing body of evidence illustrates AM as a pivotal component in normal physiology and disease with marked beneficial effects in the host defense mechanism. Exogenous administration of AM as well as its ectopic overexpression and the use of drugs, which potentiates its activity, are promising strategies for treatment of septic shock and several other pathogen-related disorders. Although major progress toward this end has been achieved over the past few years, our further understanding of the pleiotropic mechanisms involved with AM as a protective peptide is paramount to maximize its clinical application.     

Growth, differentiation, and migration of osteoblasts on transparent Ni doped TiO2 thin films deposited on borosilicate glass

A simple and cost effective dip coating method was used to deposit thin films of amorphous (AM) or anatase (AN) titanium dioxide (TiO(2)) on borosilicate glass substrates, either with or without prior doping of TiO(2) with nickel (Ni) cations by a specially designed sol gel technique. The objective of the study was to compare the physicochemical and biological properties of these films and assess their use in orthopedic implants or for in vitro cell biological studies. Analytical techniques such as XRD and XPS, in combination with ATR-FTIR and SEM revealed that only AN films, prepared by controlled heating up to 450°C, irrespective of prior doping with Ni, contained significant crystalline structures of variable morphologies. This observation could be linked to the carbon and oxygen contents and the availability of functional groups in the films. Cell biological studies revealed that Ni doping of TiO(2) in both AM and AN films improved the adhesion, spreading, proliferation, differentiation, and migration of MC3T3 cells. Our studies provide a new approach to prepare optically transparent metal surfaces, with tunable physicochemical properties, which could be suitable for eliciting optimal osteoinductive cell responses and permit the detailed in vitro cell biological studies of osteoblasts.     

生物羊膜冷冻干燥工艺优化研究

为探索羊膜冷冻干燥保存的最佳工艺条件,取健康剖宫产产妇胎盘,钝性剥离羊膜。以保存羊膜组织形态变化、胶原蛋白酶降解速度、生物力学特征、细胞因子含量为考察指标,对羊膜冷冻干燥工艺中的关键因素进行优化。结果显示,改良冷冻干燥羊膜上皮细胞、纤维基质层形态结构与新鲜羊膜基本相同,但纤维基质厚度略有增加,上皮细胞表面微绒毛略有减少;Ⅳ型胶原酶在溶液中降解速度有所加快;生物力学特征与新鲜羊膜无明显差别;6种细胞因子含量明显低于新鲜羊膜。结合前期工作,与常规冷冻干燥法比较,改良冷冻干燥工艺对保存羊膜组织结构和生物学活性因子影响较小,并能使保存羊膜具有更好的生物力学特性。     

The effects of acellular amniotic membrane matrix on osteogenic differentiation and ERK1/2 signaling in human dental apical papilla cells

The amniotic membrane (AM) has been widely used in the field of tissue engineering because of the favorable biological properties for scaffolding material. However, little is known about the effects of an acellular AM matrix on the osteogenic differentiation of mesenchymal stem cells. In this study, it was found that both basement membrane side and collagenous stroma side of the acellular AM matrix were capable of providing a preferential environment for driving the osteogenic differentiation of human dental apical papilla cells (APCs) with proven stem cell characteristics. Acellular AM matrix potentiated the induction effect of osteogenic supplements (OS) such as ascorbic acid, β-glycerophosphate, and dexamethasone and enhanced the osteogenic differentiation of APCs, as seen by increased core-binding factor alpha 1 (Cbfa-1) phosphorylation, alkaline phosphatase activity, mRNA expression of osteogenic marker genes, and mineralized matrix deposition. Even in the absence of soluble OS, acellular AM matrix also could exert the substrate-induced effect on initiating APCs’ differentiation. Especially, the collagenous stroma side was more effective than the basement membrane side. Moreover, the AM-induced effect was significantly inhibited by U0126, an inhibitor of extracellular signaling-regulated kinase 1/2 (ERK1/2) signaling. Taken together, the osteogenic differentiation promoting effect on APCs is AM-specific, which provides potential applications of acellular AM matrix in bone/tooth tissue engineering.