Search | Engineering

订阅投稿

首页工程期刊工程焦点工程成就工程前沿关于我们 English

资源类型

期刊论文 629

年份

2024 1

2023 44

2022 55

2021 62

2020 35

2019 61

2018 38

2017 42

2016 24

2015 35

2014 29

2013 33

2012 17

2011 24

2010 21

2009 30

2008 16

2007 20

2006 2

2005 3

展开︾

关键词

燃料电池 7

固体氧化物燃料电池 4

人工智能 3

干细胞 3

COVID-19 2

SOFC 2

临床试验 2

人–信息–物理系统 2

人机协作 2

催化剂 2

新一代智能制造 2

氢燃料电池 2

氢能 2

间充质干细胞 2

高压 2

2035 1

21世纪 1

3D支架平台 1

3D细胞容器 1

展开︾

检索范围：

排序：展示方式：

Dental stem cell and dental tissue regeneration

Qiming Zhai, Zhiwei Dong, Wei Wang, Bei Li, Yan Jin

《医学前沿（英文）》 2019年第13卷第2期页码 152-159 doi: 10.1007/s11684-018-0628-x

摘要： The teeth are highly differentiated chewing organs formed by the development of tooth germ tissue located in the jaw and consist of the enamel, dentin, cementum, pulp, and periodontal tissue. Moreover, the teeth have a complicated regulatory mechanism, special histologic origin, diverse structure, and important function in mastication, articulation, and aesthetics. These characteristics, to a certain extent, greatly complicate the research in tooth regeneration. Recently, new ideas for tooth and tissue regeneration have begun to appear with rapid developments in the theories and technologies in tissue engineering. Numerous types of stem cells have been isolated from dental tissue, such as dental pulp stem cells (DPSCs), stem cells isolated from human pulp of exfoliated deciduous teeth (SHED), periodontal ligament stem cells (PDLSCs), stem cells from apical papilla (SCAPs), and dental follicle cells (DFCs). All these cells can regenerate the tissue of tooth. This review outlines the cell types and strategies of stem cell therapy applied in tooth regeneration, in order to provide theoretical basis for clinical treatments.

关键词： stem cells pulp regeneration periodontal regeneration

HTML PDF 收藏

Effect of incorporating Elaeagnus angustifolia extract in PCL-PEG-PCL nanofibers for bone tissue engineering

Vahideh R. Hokmabad, Soodabeh Davaran, Marziyeh Aghazadeh, Effat Alizadeh, Roya Salehi, Ali Ramazani

《化学科学与工程前沿（英文）》 2019年第13卷第1期页码 108-119 doi: 10.1007/s11705-018-1742-7

摘要：

Plants have been used for medicinal purposes for thousands of years but they are still finding new uses in modern times. For example, Elaeagnus angustifolia (EA) is a medicinal herb with antinociceptive, anti-inflammatory, antibacterial and antioxidant properties and it is widely used in the treatment of rheumatoid arthritis and osteoarthritis. EA extract was loaded onto poly(ϵ-caprolactone)-poly(ethylene glycol)-poly(ϵ-caprolactone) (PCL-PEG-PCL/EA) nanofibers and their potential applications for bone tissue engineering were studied. The morphology and chemical properties of the fibers were evaluated using Fourier transform infrared spectroscopy, field emission scanning electron microscopy, contact angle measurements and mechanical tests. All the samples had bead-free morphologies with average diameters ranging from 100 to 200 nm. The response of human cells to the PCL-PEG-PCL/EA nanofibers was evaluated using human dental pulp stem cells (hDPSCs). The hDPSCs had better adhesion and proliferation capacity on the EA loaded nanofibers than on the pristine PCL-PEG-PCL nanofibers. An alizarin red S assay and the alkaline phosphatase activity confirmed that the nanofibrous scaffolds induced osteoblastic performance in the hDPSCs. The quantitative real time polymerase chain reaction results confirmed that the EA loaded nanofibrous scaffolds had significantly upregulated gene expression correlating to osteogenic differentiation. These results suggest that PCL-PEG-PCL/EA nanofibers might have potential applications for bone tissue engineering.

关键词： Elaeagnus angustifolia scaffold electrospinning human dental pulp stem cell tissue engineering

HTML PDF 收藏

Advancement of human leukocyte antigen-partially matched related hematopoietic stem cell transplantation

null

《医学前沿（英文）》 2013年第7卷第3期页码 306-315 doi: 10.1007/s11684-013-0279-x

摘要：

Allogeneic hematopoietic stem cell transplantation (HSCT) is one of the most effective options for hematological malignancies, and human leukocyte antigen-partially matched related donors (PMRDs) are a valuable option for HSCT. Several protocols (with or without ex vivo T-cell depletion (TCD)) have been established worldwide. TCD including CD34⁺positive selection and CD3/CD19 depletion has successfully overcome the human leukocyte antigen disparity. However, TCD is associated with prolonged immune deficiencies, increased risks of infectious complications, and high transplantation-related mortality. PMRD HSCT without ex vivo TCD is well developed, and numerous patients have benefitted from it. Here, we review the literature on PMRD HSCT.

关键词： partially matched related donor hematopoietic stem cell transplantation allogeneic

HTML PDF 收藏

Self-etching adhesives: possible new pulp capping agents to vital pulp therapy

null

《医学前沿（英文）》 2011年第5卷第1期页码 77-79 doi: 10.1007/s11684-010-0104-8

摘要：

Pulp capping is one of the solving for keeping vital pulp in the case of dentin caries, reversible pulpitis or traumatic pulp exposure. The presence of bacteria on the cavity walls or in the pulp was the major factor that leads to the failure of pulp capping. Traditional pulp capping agent, calcium hydroxide, may not prevent microleakage. Self-etching system is a newly developed adhesive system, which could provide less microleakage and would not break down or dissolve, preventing the oral fluids and bacteria from the pulp along the cavity wall. This may reduce such clinical problems as postoperative sensitivity, secondary caries and marginal discoloration. Researches showed that some kinds of self-etching adhesives induced the mild to moderate inflammatory pulp response, with negative bacterial staining. Inclusion of antibacterial components into self-etching system, such as 12- methacryloyloxydodecylpyridinium bromide (MDPB) may inhibit bacteria and provide better clinical effects. It is speculated that using the self-etching adhesive system containing the antibacterial agent, such as MDPB, to the dental pulp directly or indirectly, may inhibit bacteria after the placement of restoration as well as residual bacteria in the cavity.

关键词： dental pulp pulp capping self-etching adhesives antibacterial components

HTML PDF 收藏

Immunohistochemical characterization of hepatic stem cell-related cells in developing human liver

XU Jun, HU Yong, WANG Jian, ZHANG Taiping, ZHOU Ji, YU Hongyu

《医学前沿（英文）》 2007年第1卷第3期页码 264-268 doi: 10.1007/s11684-007-0050-2

摘要： Little is known about the expression characteristics of the various kinds of possible markers in hepatic stem cells (HSCs) and other HSC-related cells in human fetal liver in various developmental stages. It is significant to investigate the immunohistochemical expression for better understanding of the origin, differentiation and migration of HSCs in the developing human liver. H-E staining and immunohistochemical methods were used to observe the expression of hepatic/cholangiocellular differentiation markers (AFP, GST-, CK7, CK19) and hematopoietic stem cell markers (CD34 and c-kit) in several kinds of HSC-related cells in thirty cases of fetal liver samples (4–35 weeks after pregnancy). AFP expression appears in fetal hepatocytes at four weeks’ gestation. It peaks at 16–24 weeks’ gestation and decreases gradually afterwards. Finally, weak signals were only found in some ductal plate cells and a few limiting plate cells. GST- was detected in hepatic cord cells from the sixth week and in the ductal plate cells from the eighth week. Twenty-six weeks later, only some ductal plate cells and a few limiting plate cells show positive signals. CK19 expression peaks during the 6th–11th weeks in hepatic cord cells and decreases gradually afterwards, except for the ductal plates. CK7 expression was limited in the ductal plate cells and bile ducts cells from the 14th week. CD34 and c-kit were detected at the eighth week in some ductal plate cells and a few mononuclear cells in the hepatic cords/mesenchymal tissue of portal areas. After 21 weeks, CD34 and c-kit were found only in ductal plate cells and a few mononuclear cells in the hepatic mesenchymal tissue of portal areas. Fetal hepatocytes at 4–16 weeks’ gestation are mainly constituted by HSCs characterized with bi-potential differentiation capacity. At 16 weeks’ gestation, most hepatic cord cells begin to differentiate into hepatocytes and abundant HSCs remain in ductal plate (the origin site of Hering canals). It is also indicated that the hematopoietic stem cells may give rise to some HSCs in embryonic liver. These indirectly support the hypothesis about the location and origin of HSCs in liver valley hypothesis reported previously.

关键词： origin Little mesenchymal tissue cords/mesenchymal tissue CD34

HTML PDF 收藏

人类诱导性多能干细胞稳定生产的最新进展 Review

Ikki Horiguchi, Masahiro Kino-oka

《工程（英文）》 2021年第7卷第2期页码 144-152 doi: 10.1016/j.eng.2021.01.001

摘要：

诱导性多能干细胞（iPSC）在许多方面，如再生医学和药物筛选方面，是理想的细胞来源，其开发前景广阔。但是，目前还没有一种有效的大规模生产系统来确保诱导性多能干细胞的稳定供应。本文综述了近年来为了实现诱导性多能干细胞的稳定生产所采取的方法。本文首先讨论了诱导性多能干细胞培养过程中需要控制的因素，如养分供应、废物清除和氧气供应。然后，介绍了基于黏附、悬浮和支架的诱导性多能干细胞培养系统的最新研究。本文还讨论了细胞培养阶段之后进行的过程，如灌装和冻存过程，由于细胞悬浮液在超低温保存培养基中存活率降低，所以其生产规模受到了限制。最后，我们总结了实现诱导性多能干细胞稳定生产的可能性，并强调了仍有待克服的局限性。本文表明为了获得最佳且稳定的大规模生产诱导性多能干细胞系统，运用多学科研究手段对研究影响细胞生长和质量的复杂因素是至关重要的。

关键词：诱导性多能干细胞细胞生产扩增灌装冻存

HTML PDF 收藏

The unregulated commercialization of stem cell treatments: a global perspective

Douglas Sipp

《医学前沿（英文）》 2011年第5卷第4期页码 348-355 doi: 10.1007/s11684-011-0150-x

摘要： Research into the biological properties and clinical potential of stem cells has spurred strong public investment, industry development, media coverage, and patient interest in recent years. To date, however, few clinical applications of demonstrated safety and efficacy have been developed with the exception of uses of hematopoietic stem cells in the treatment of diseases of the blood and immune systems. This lack of an evidence basis notwithstanding, hundreds of companies and private clinics around the world now sell putative stem cell treatments for an enormously broad range of medical and quality-of-life conditions. This represents a major challenge for legitimate scientists working in the field, for authorities seeking to protect their constituencies, and for patients and consumers targeted by such companies’ marketing strategies. In this review, I provide an overview of the global industry in pseudomedical stem cell treatments, with an investigation of claims in a single disease area (amyotrophic lateral sclerosis), and make recommendations for the introduction and enforcement of appropriate regulatory responses to this problem.

关键词： stem cell tourism medical ethics stem cell policy and regulation alternative medicine

HTML PDF 收藏

Implantation of human umbilical cord mesenchymal stem cells for ischemic stroke: perspectives and challenges

null

《医学前沿（英文）》 2015年第9卷第1期页码 20-29 doi: 10.1007/s11684-014-0371-x

摘要：

Ischemic stroke is a focal cerebral insult that often leads to many adverse neurological complications severely affecting the quality of life. The prevalence of stroke is increasing throughout the world, while the efficacy of current pharmacological therapies remains unclear. As a neuroregenerative therapy, the implantation of human umbilical cord mesenchymal stem cells (hUC-MSCs) has shown great possibility to restore function after stroke. This review article provides an update role of hUC-MSCs implantation in the treatment of ischemic stroke. With the unique “immunosuppressive and immunoprivilege” property, hUC-MSCs are advised to be an important candidate for allogeneic cell treatment. Nevertheless, most of the treatments are still at primary stage and not clinically feasible at the current time. Several uncertain problems, such as culture conditions, allograft rejection, and potential tumorigenicity, are the choke points in this cellular therapy. More preclinical researches and clinical studies are needed before hUC-MSCs implantation can be used as a routinely applied clinical therapy.

关键词： cellular therapy transplantation human umbilical cord mesenchymal stem cells ischemic stroke

HTML PDF 收藏

Production of pectic extracts from sugar beet pulp with antiproliferative activity on a breast cancercell line

Jacqueline CONCHA, Caroline WEINSTEIN, María Elvira Zú?IGA

《化学科学与工程前沿（英文）》 2013年第7卷第4期页码 482-489 doi: 10.1007/s11705-013-1342-5

摘要： In the last years, sugar beet pectins have been the subject of several investigations involving extraction methodologies, chemical composition and functional properties. The structure of pectins, which depends on the extraction method, is decisive in their capacity to induce apoptosis on several cancer cell lines like colon, prostate and breast. In this work, sugar beet pectin extraction was performed in the following steps: lipid extraction with hexane, removal of soluble complex carbohydrates and proteins, and enzymatic treatment with amyloglucosidase, protease, and pectinase. The enzymatic treatment was carried out with Rohapect DA6L under the following conditions: 50°C, pH 4.0, 2% enzyme/substrate (E/S) ratio, 15 h, and a solid to liquid ratio of 1 ∶ 10. The pectic extract showed a degree of polymerization (DP) profile of 55.8% with DP≥7; 4.9% with DP6; 5.8% between DP2 and DP6 ; 4.7% with DP2; and 28.8% with DP1. The pectic extract was examined for its antiproliferative activity on the MCF-7 breast cancer cell line. At a concentration range of 12.5–25 mg/mL the pectic extract killed 80.6% of the cells, exhibiting a higher antiproliferative activity than 4-hydroxytamoxifen (4-OHT), a classical anticancer drug, which killed 56.5% of the cells.

关键词： pectic extracts antiproliferative activity breast cancer enzymatic treatment

HTML PDF 收藏

The regulatory sciences for stem cell-based medicinal products

null

《医学前沿（英文）》 2014年第8卷第2期页码 190-200 doi: 10.1007/s11684-014-0323-5

摘要：

Over the past few years, several new achievements have been made from stem cell studies, many of which have moved up from preclinical stages to early, or from early to middle or late, stages thanks to relatively safe profile and preliminary evidence of effectiveness. Moreover, some stem cell-based products have been approved for marketing by different national regulatory authorities. However, many critical issues associated mainly with incomplete understanding of stem cell biology and the relevant risk factors, and lack of effective regulations still exist and need to be urgently addressed, especially in countries where establishment of appropriate regulatory system just commenced. More relevantly, the stem cell regulatory sciences need to be established or improved to more effectively evaluate quality, safety and efficacy of stem cell products, and for building up the appropriate regulatory framework. In this review, we summarize some new achievements in stem cell studies, especially the preclinical and clinical studies, the existing regulations, and the associated challenges, and we then propose some considerations for improving stem cell regulatory sciences with a goal of promoting the steadfast growth of the well-regulated stem cell therapies abreast of evolvement of stem cell sciences and technologies.

关键词： stem cell-based medicinal products (SCMPs) stem cell therapy (SCT) safety effectiveness standards guidelines regulatory science

HTML PDF 收藏

Therapeutic potential of stem cell in liver regeneration

null

《医学前沿（英文）》 2011年第5卷第1期页码 26-32 doi: 10.1007/s11684-011-0107-0

摘要：

Liver transplantation is the only life-saving procedure for patients with end-stage liver disease. However, its potential benefits are hampered by many disadvantages, such as the relative shortage of donors, operative risks, and high costs. These issues have prompted the search for new alternative therapies for irreversible liver disease. Stem cell therapy, with the ability for self-renewal and potential for multilineage differentiation, is a promising alternative approach. Several studies have demonstrated that transplantation of hepatic stem/progenitor cells or hepatocyte-like cells derived from multipotent stem cells leads to donor cell-mediated repopulation of the liver and improved survival rates in experimental models of liver disease. However, a registered clinical application based on stem cell technology will take at least an additional 5 to 10 years because of some limitations; e.g. the lack of suitable cell sources and risk of teratoma formation. This review summarizes the general understanding of the therapeutic potentials of stem cells in liver disease, including the sources, mechanisms, and delivery methods of hepatic stem cells in liver regeneration, and discusses some challenges for their therapeutic application.

关键词： stem cell liver disease regenerative medicine

HTML PDF 收藏

Stem cell niches and endogenous electric fields in tissue repair

null

《医学前沿（英文）》 2011年第5卷第1期页码 40-44 doi: 10.1007/s11684-011-0108-z

摘要：

Adult stem cells are responsible for homeostasis and repair of many tissues. Endogenous adult stem cells reside in certain regions of organs, known as the stem cell niche, which is recognized to have an important role in regulating tissue maintenance and repair. In wound healing and tissue repair, stem cells are mobilized and recruited to the site of wound, and participate in the repair process. Many regulatory factors are involved in the stem cell-based repair process, including stem cell niches and endogenous wound electric fields, which are present at wound tissues and proved to be important in guiding wound healing. Here we briefly review the role of stem cell niches and endogenous electric fields in tissue repair, and hypothesize that endogenous electric fields become part of stem cell niche in the wound site.

关键词： stem cell stem cell niche electric field tissue repair

HTML PDF 收藏

Transcriptomics and proteomics in stem cell research

null

《医学前沿（英文）》 2014年第8卷第4期页码 433-444 doi: 10.1007/s11684-014-0336-0

摘要：

Stem cells are capable of self-renewal and differentiation, and the processes regulating these events are among the most comprehensively investigated topics in life sciences. In particular, the molecular mechanisms of the self-renewal, proliferation, and differentiation of stem cells have been extensively examined. Multi-omics integrative analysis, such as transcriptomics combined with proteomics, is one of the most promising approaches to the systemic investigation of stem cell biology. We reviewed the available information on stem cells by examining published results using transcriptomic and proteomic characterization of the different stem cell processes. Comprehensive understanding of these important processes can only be achieved using a systemic methodology, and employing such method will strengthen the study on stem cell biology and promote the clinical applications of stem cells.

关键词： embryonic stem cells transcriptomics proteomics

HTML PDF 收藏

Human menstrual blood-derived stem cells alleviate autoimmune hepatitis via JNK/MAPK signaling pathway

《医学前沿（英文）》 2023年第17卷第3期页码 534-548 doi: 10.1007/s11684-022-0953-y

摘要： Autoimmune hepatitis (AIH) is a severe globally distributed liver disease that could occur at any age. Human menstrual blood-derived stem cells (MenSCs) have shown therapeutic effect in acute lung injury and liver failure. However, their role in the curative effect of AIH remains unclear. Here, a classic AIH mouse model was constructed through intravenous injection with concanavalin A (Con A). MenSCs were intravenously injected while Con A injection in the treatment groups. The results showed that the mortality by Con A injection was significantly decreased by MenSCs treatment and liver function tests and histological analysis were also ameliorated. The results of phosphoproteomic analysis and RNA-seq revealed that MenSCs improved AIH, mainly by apoptosis and c-Jun N-terminal kinase/mitogen-activated protein signaling pathways. Apoptosis analysis demonstrated that the protein expression of cleaved caspase 3 was increased by Con A injection and reduced by MenSCs transplantation, consistent with the TUNEL staining results. An AML12 co-culture system and JNK inhibitor (SP600125) were used to verify the JNK/MAPK and apoptosis signaling pathways. These findings suggested that MenSCs could be a promising strategy for AIH.

关键词： autoimmune hepatitis (AIH) concanavalin A (Con A) human menstrual blood-derived stem cells (MenSCs) apoptosis mitogen-activated protein kinase (MAPK)

HTML PDF 收藏

Cannabidiol prevents depressive-like behaviors through the modulation of neural stem cell differentiation

《医学前沿（英文）》 2022年第16卷第2期页码 227-239 doi: 10.1007/s11684-021-0896-8

摘要： Chronic stress impairs radial neural stem cell (rNSC) differentiation and adult hippocampal neurogenesis (AHN), whereas promoting AHN can increase stress resilience against depression. Therefore, investigating the mechanism of neural differentiation and AHN is of great importance for developing antidepressant drugs. The nonpsychoactive phytocannabinoid cannabidiol (CBD) has been shown to be effective against depression. However, whether CBD can modulate rNSC differentiation and hippocampal neurogenesis is unknown. Here, by using the chronic restraint stress (CRS) mouse model, we showed that hippocampal rNSCs mostly differentiated into astrocytes under stress conditions. Moreover, transcriptome analysis revealed that the FoxO signaling pathway was involved in the regulation of this process. The administration of CBD rescued depressive-like symptoms in CRS mice and prevented rNSCs overactivation and differentiation into astrocyte, which was partly mediated by the modulation of the FoxO signaling pathway. These results revealed a previously unknown neural mechanism for neural differentiation and AHN in depression and provided mechanistic insights into the antidepressive effects of CBD.

关键词： cannabidiol depression radial neural stem cells neurogenesis