Fourier Transform Infrared Microspectroscopy Method to Determine Stress in Sapphire

Fourier transform infrared microspectroscopy was used to nondestructively measure stress in ceramics, with sapphire being the model material. An infrared transmitting microscope was used to investigate, via external reflectance, spatial areas as small as 100 μm.     

红外显微光谱法测定生活饮用水中微塑料

建立生活饮用水中微塑料的红外显微光谱测定方法.5 L水样经不锈钢滤膜过滤,用30％H2O2对滤膜上的物质消解2 d(40℃,24 h;常温,24 h),然后用超纯水在30℃条件下超声洗脱20 min,用银膜过滤洗脱液,用傅里叶红外显微光谱仪ATR成像模式进行定性和定量分析.结果显示,该方法的加标回收率为73.1％～92...     

Mesenchymal Stem Cells and Induced Pluripotent Stem Cells as Therapies for Multiple Sclerosis

Multiple sclerosis (MS) is a chronic, autoimmune, inflammatory demyelinating disorder of the central nervous system that leads to permanent neurological deficits. Current MS treatment regimens are insufficient to treat the irreversible neurological disabilities. Tremendous progress in the experimental and clinical applications of cell-based therapies has recognized stem cells as potential candidates for regenerative therapy for many neurodegenerative disorders including MS. Mesenchymal stem cells (MSC) and induced pluripotent stem cell (iPSCs) derived precursor cells can modulate the autoimmune response in the central nervous system (CNS) and promote endogenous remyelination and repair process in animal models. This review highlights studies involving the immunomodulatory and regenerative effects of mesenchymal stem cells and iPSCs derived cells in animal models, and their translation into immunomodulatory and neuroregenerative treatment strategies for MS.     

Stem Cells: The Pursuit of Genomic Stability

Stem cells harbor significant potential for regenerative medicine as well as basic and clinical translational research. Prior to harnessing their reparative nature for degenerative diseases, concerns regarding their genetic integrity and mutation acquisition need to be addressed. Here we review pluripotent and multipotent stem cell response to DNA damage including differences in DNA repair kinetics, specific repair pathways (homologous recombination vs. non-homologous end joining), and apoptotic sensitivity. We also describe DNA damage and repair strategies during reprogramming and discuss potential genotoxic agents that can reduce the inherent risk for teratoma formation and mutation accumulation. Ensuring genomic stability in stem cell lines is required to achieve the quality control standards for safe clinical application.     

傅里叶变换红外光谱法检验塑料吸管的研究

利用傅里叶变换红外光谱仪,对塑料吸管样本分析检验。依据红外光谱图中吸收峰,可以将塑料吸管样本加以区分。该检验方法不破坏检材,重现性好,可用于鉴定塑料吸管物证。     

Isolation of Multipotent Nestin-Expressing Stem Cells Derived from the Epidermis of Elderly Humans and TAT-VHL Peptide-Mediated Neuronal Differentiation of These Cells

A specialized population of cells residing in the hair follicle is quiescent but shows pluripotency for differentiating into epithelial-mesenchymal lineage cells. Therefore, such cells are hoped to be useful as implantable donor cells for regenerative therapy. Recently, it was reported that intracellular delivery of TAT-VHL peptide induces neuronal differentiation of skin-derived precursors. In the present study, we successfully isolated multipotent stem cells derived from the epidermis of elderly humans, characterized these cells as being capable of sphere formation and strong expression of nestin, fibronectin, and CD34 but not of keratin 15, and identified the niche of these cells as being the outer root sheath of the hair follicles. In addition, we showed that TAT-VHL peptide induced their neuronal differentiation in vitro, and confirmed by fluorescence immunohistochemistry the neuronal differentiation of such peptide-treated cells implanted into rodent brains. These multipotent nestin-expressing stem cells derived from human epidermis are easily accessible and should be useful as donor cells for neuronal regenerative cell therapy.     

诱导多能干细胞重编程方法的优化及其在航天医学中的应用展望

近年来,通过外源导入特定的转录因子,将体细胞重编程为类似胚胎干细胞（ESCs）潜能的诱导多能干细胞（iPSCs）掀起了干细胞研究的又一热潮,然而重编程效率低和安全性等问题严重阻碍着其临床应用.太空环境对成体干细胞分化潜能的影响是航天员生理变化的因素之一,具有类似ESCs全能性的iPSCs将为发育生理学及再生医学研究带来全新的视角.综述了iPSCs的研究进展,重点阐述提高安全性和重编程效率的方法和应用研究现状,并探讨了其在航天医学领域中的应用前景.     

红外光谱技术的进展及其应用

对漫反射、衰减全反射傅里叶变换红外光谱和差谱等技术及其应用进行了简单介绍     

Proteomics-Based Analysis of Protein Complexes in Pluripotent Stem Cells and Cancer Biology

A protein complex consists of two or more proteins that are linked together through protein–protein interactions. The proteins show stable/transient and direct/indirect interactions within the protein complex or between the protein complexes. Protein complexes are involved in regulation of most of the cellular processes and molecular functions. The delineation of protein complexes is important to expand our knowledge on proteins functional roles in physiological and pathological conditions. The genetic yeast-2-hybrid method has been extensively used to characterize protein-protein interactions. Alternatively, a biochemical-based affinity purification coupled with mass spectrometry (AP-MS) approach has been widely used to characterize the protein complexes. In the AP-MS method, a protein complex of a target protein of interest is purified using a specific antibody or an affinity tag (e.g., DYKDDDDK peptide (FLAG) and polyhistidine (His)) and is subsequently analyzed by means of MS. Tandem affinity purification, a two-step purification system, coupled with MS has been widely used mainly to reduce the contaminants. We review here a general principle for AP-MS-based characterization of protein complexes and we explore several protein complexes identified in pluripotent stem cell biology and cancer biology as examples.     

傅立叶变换红外光谱法测定黄姜中皂素含量

直接对黄姜进行压片,利用傅立叶变换红外光谱法测定黄姜中皂素含量.结果表明,以1647 cm-1处的吸收峰作为分析峰,在0.5%～5.0%含量范围内峰面积和含量具有良好的线性关系,相关系数为0.9690,加标回收率为99.12%,相对标准偏差RSD为0.22%.测定结果与传统的重量分析法相近,实现了黄姜中皂素含量的无损分析.     

Generation of Bladder Urothelium from Human Pluripotent Stem Cells under Chemically Defined Serum- and Feeder-Free System

Human stem cells are promising sources for bladder regeneration. Among several possible sources, pluripotent stem cells are the most fascinating because they can differentiate into any cell type, and proliferate limitlessly in vitro. Here, we developed a protocol for differentiation of human pluripotent stem cells (hPSCs) into bladder urothelial cells (BUCs) under a chemically defined culture system. We first differentiated hPSCs into definitive endoderm (DE), and further specified DE cells into BUCs by treating retinoic acid under a keratinocyte-specific serum free medium. hPSC-derived DE cells showed significantly expressed DE-specific genes, but did not express mesodermal or ectodermal genes. After DE cells were specified into BUCs, they notably expressed urothelium-specific genes such as UPIb, UPII, UPIIIa, P63 and CK7. Immunocytochemistry showed that BUCs expressed UPII, CK8/18 and P63 as well as tight junction molecules, E-CADHERIN and ZO-1. Additionally, hPSCs-derived BUCs exhibited low permeability in a FITC-dextran permeability assay, indicating BUCs possessed the functional units of barrier on their surfaces. However, BUCs did not express the marker genes of other endodermal lineage cells (intestine and liver) as well as mesodermal or ectodermal lineage cells. In summary, we sequentially differentiated hPSCs into DE and BUCs in a serum- and feeder-free condition. Our differentiation protocol will be useful for producing cells for bladder regeneration and studying normal and pathological development of the human bladder urothelium in vitro.     

高纯六氟乙烷中氯化氢的傅里叶变换红外定量分析

电子行业用作清洗和蚀刻的特种气体六氟乙烷对杂质组分HCl的含量要求严格控制在一定范围,本文建立了用傅里叶变换红外光谱仪分析其中HCl杂质的分析方法,并实现了对产品中HCl的定量分析。     

傅立叶变换红外光谱法剖析未知结垢物

采用傅立叶变换红外光谱法对生产装置产生的未知物进行剖析研究,结果表明,用红外光谱法可以测定出该未知物的组成。并且该方法分析速度快,重现性好,成本低,结果令人满意。     

傅立叶变换红外光谱法鉴别几种纤维材质

采用傅立叶变换红外光谱仪对几种纤维的材质进行了鉴别,经对比红外光谱图,确认了几种纤维的材质为等规聚丙烯。     

FT-NIR快速测定烟叶及卷烟烟丝中挥发碱的含量

采用傅立叶变换近红外光谱技术采集烤烟烟叶和卷烟烟丝样品的近红外光谱,结合水蒸汽蒸馏法测定样品中挥发碱含量的数据,采用偏最小二乘法(PLS)分别建立了预测烤烟烟叶和国内品牌卷烟烟丝中挥发碱含量的近红外模型,两种模型的相关系数分别为0.95396和0.96558。进行了准确性和重复性实验。实验表明,近红外光谱法与标准方法之间不存在显著性差异,可以很好的应用于两类样品挥发碱含量的快速检测。     

傅里叶变换红外光谱法测定白酒中乙醇含量

建立快速测定酒精饮品中乙醇含量的衰减全反射-傅里叶变换红外光谱（ATR-FTIR）法,以ZnSe槽行板为ATR晶体,以水为背景采集样品的FTIR图。以1 044 cm-1的C-OH伸缩振动为特征峰,用峰面积表示整个吸光度以消除尖峰干扰,建立了其线性关系数0.998 6,乙醇水溶液的检测限为0.2%。该方法准确、方便、快速,适用于酒精饮品中乙醇含量的快速测定。     

傅立叶变换红外光谱法在高聚物研究中的应用

本文介绍了红外光谱的相关知识、测定原理,以及采用傅立叶变换红外光谱仪对几种高聚物进行结构剖析的实例。结果表明,用红外光谱法可以准确地剖析出高聚物的组成,该方法分析速度快,重现性好,结果令人满意。     

傅立叶变换红外光谱法对焦油中未知物成分的剖析研究

本文介绍了一种傅立叶变换红外光谱仪在生产过程中的应用。该方法测定手续简便,分析速度快,效率高,重现性好,可做为一种常规分析方法在试验室中应用。本文列举了黑色焦油中未知物的剖析研究实例。     

Epidermal Stem Cells in Orthopaedic Regenerative Medicine

In the last decade, great advances have been made in epidermal stem cell studies at the cellular and molecular level. These studies reported various subpopulations and differentiations existing in the epidermal stem cell. Although controversies and unknown issues remain, epidermal stem cells possess an immune-privileged property in transplantation together with easy accessibility, which is favorable for future clinical application. In this review, we will summarize the biological characteristics of epidermal stem cells, and their potential in orthopedic regenerative medicine. Epidermal stem cells play a critical role via cell replacement, and demonstrate significant translational potential in the treatment of orthopedic injuries and diseases, including treatment for wound healing, peripheral nerve and spinal cord injury, and even muscle and bone remodeling.