生物物理化学
Online ISSN : 1349-9785
Print ISSN : 0031-9082
ISSN-L : 0031-9082
48 巻, 4 号
選択された号の論文の12件中1~12を表示しています
  • 福田 信治, 田賀 哲也
    2004 年 48 巻 4 号 p. 123-127
    発行日: 2004/12/15
    公開日: 2009/03/31
    ジャーナル フリー
    Neurons, astrocytes and oligodendrocytes arise from common progenitor cells that reside in the neuroepithelium of the developing brain. We have focused on cytokines as astrocyte-inducing cell external cues, and found that leukemia inhibitory factor (LIF) and bone morphogenetic protein 2 (BMP2) synergistically induce glial fibrillary acidic protein (GFAP)-positive astrocytes. The synergistic action of these two cytokines is achieved by the complex formation between respective downstream transcription factors, STAT3 and Smad1, bridged by a transcriptional coactivator p300. Simultaneously, BMP2 also represses the differentiation of neurons by inducing anti-neurogenic basic helix-loop-helix (bHLH) transcription factors, Id1, Id3 and Hes-5. Astrocyte-inducing cytokines not only promote astrocytogenesis but also inhibit neurogenesis, suggesting the presence of negative interaction between neuronal and astrocytic differentiation pathways. We also found that oligodendrocytic bHLH factor OLIG2 inhibits the LIF-induced transcription of GFAP gene by abolishing the complex formation between STAT3 and p300. This suggests the presence of negative interaction between astrocytic and oligodendrocytic cell lineages, same as has been observed for neuronal and astrocytic cell lineages. Interestingly, differentiation of neuroepithelial cells depends on cell intrinsic programs, in addition to cell external cues. In contrast to embryonic day 14.5 (E14.5) neuroepithelial cells, LIF is not sufficient to induce GFAP expression in E11.5 neuroepithelial cells. Analysis of the GFAP gene promoter revealed that CpG dinucleotide sequences within the STAT3 recognition site is methylated in E11.5 neuroepithelial cells, and this methylation leads to the inaccessibility of activated STAT3 to its binding elements. The methylation frequency in the STAT3 binding site in the GFAP promoter declines as the developmental process proceeds, allowing the expression of GFAP in astrocytic cell lineage. The results suggest that lineage specification is regulated by cell-external cues and cell-intrinsic programs, where the former involves extracellular cytokines and the latter includes DNA methylation of cell lineage specific gene promoters. Our work also suggests the presence of negative regulatory interactions among the signals that promote differentiation of neurons, astrocytes and oligodendrocytes.
  • 池田 宇一
    2004 年 48 巻 4 号 p. 129-131
    発行日: 2004/12/15
    公開日: 2009/03/31
    ジャーナル フリー
    Epidemiological studies in Western countries indicate that up to 5% of men and 2.5% of women 60 years of age or older have symptoms of intermittent claudication. The symptoms of chronic arterial insufficiency of the lower extremities progress rather slowly over time. Thus, after 5 to 10 years, more than 70% of patients report either no change or improvement in their symptoms, while 20% to 30% have progressive symptoms and require intervention, and less than 10% need amputation.
    With respect to affected limbs, the goal is to eliminate ischemic symptoms and prevent progression to vascular occlusion. Accepted treatments include nonsurgical measures such as exercise, risk factor modification, and pharmacological therapy, as well as surgical treatment, which includes interventional radiological procedures such as angioplasty or stent insertion and surgical treatment such as endarterectomy, bypass grafting, and amputation.
    Therapeutic angiogenesis by cell transplantation is another promising therapy. Recently, we have reported the effectiveness and safety of therapeutic angiogenesis by transplantation of autologous bone marrow mononuclear cells (BM-MNCs) to ischemic limbs, because of the natural ability of bone marrow cells to supply endothelial progenitor cells and secrete various angiogenic factors or cytokines. Autologous transplantation of BM-MNCs represents a new and promising strategy for clinical application designed to revascularize ischemic tissues.
  • 新井 文用, 平尾 敦, 須田 年生
    2004 年 48 巻 4 号 p. 133-138
    発行日: 2004/12/15
    公開日: 2009/03/31
    ジャーナル フリー
    幹細胞は「自分と同じ細胞と造り出す (自己複製) と同時に, 様々な種類の細胞に分化する能力 (多分化能) を持つ細胞」であり, 様々な組織・臓器でその維持・再生を担い, 幹細胞とは個体の一生を通じて, 枯渇することなく, 娘細胞を供給する. このような幹細胞システムの維持は生命の維持にとってきわめて重要である. 成体の各組織における幹細胞システムは, 幹細胞と隣接する細胞・組織との相互作用によって成り立っている. この幹細胞が維持・増殖する部位は「幹細胞ニッチ」と呼ばれ, 幹細胞はニッチにおいて細胞周期を静止した状態に保つことで, 長期にわたりその未分化性を維持していると想定される.「ニッチ」という概念は, 1970年代にヒトの造血幹細胞おいて提唱されたものであり, 概念的に, 幹細胞と幹細胞に影響を与える支持細胞などから構成されるものである. 今後, 幹細胞のニッチを制御する分子機構を理解することによって, 幹細胞の自己複製・分化といった「幹細胞の本体」の解明につながると考えられる.
  • 宮崎 純一, 宮崎 早月
    2004 年 48 巻 4 号 p. 139-141
    発行日: 2004/12/15
    公開日: 2009/03/31
    ジャーナル フリー
    Embryonic stem (ES) cells can differentiate into a wide range of well-defined cell types. Cell transplantation to restore tissue function after disease or injury is in theory applicable to a huge variety of human diseases. Thus, the use of lineage-restricted differentiation techniques developed for ES cells will promote future cell therapy. Recently, we and several groups have reported that ES cells can be induced to differentiate into insulin-producing cells. However, the efficiency of differentiation is not enough to produce insulin-secreting cells for future therapeutic use. Another potential source of beta cell regeneration is adult pancreatic stem cells. Recently, several reports showed that the prolonged culture of isolated ductal tissues from mice and humans resulted in the production of functional endocrine cells, suggesting that adult pancreatic stem cells locate at or near the ductal tissues. However, these cells tended to spontaneously differentiate and have not been fully characterized. We recently established our original methods to isolate duct epithelial cells from normal adult mouse pancreas and grow in serum-free culture. We investigated the differentiation capacity of these duct-derived cells. We showed that the duct-derived cells retained the capacity to differentiate into both pancreatic endocrine cells and hepatocytes, and were considered to be endodermal stem cells. Further studies to efficiently induce the differentiation of these cells into insulin-producing cells should afford promise of future therapeutic use of human pancreatic stem cells for diabetes patients.
  • 清島 満, 鈴木 麻希子, 前田 悟司
    2004 年 48 巻 4 号 p. 143-146
    発行日: 2004/12/15
    公開日: 2009/03/31
    ジャーナル フリー
    Although atherosclerosis progresses with age and causes various disorders, the mechanism for the formation of atherosclerosis is complicated and not fully understood. At present, several biochemical markers are known as risk factors for atherosclerosis. A new guideline for the reference value of serum lipid (total cholesterol, LDL-cholesterol, HDL-cholesterol and triglyceride) was proposed by the Japan Atherosclerosis Society in 2002. These values are utilized for the diagnosis and treatment of hyperlipidemia to protect patients from coronary heart disease (CHD). Degenerated lipoprotein has also been involved in the progression of atherosclerosis. Actually, oxidized LDL is increased in patients with CHD. Preβ1-HDL, not electrophoresed on α but on preβ position, is a unique HDL and increased in patients with CHD. Other lipoproteins such as Lp(a)and small dense LDL are also considered to be risk factors of atherosclerosis. Additionally, clinical research papers showed that gene variant of homocystein showed high homocystein level in serum and is strongly associated with the incidence of CHD. On the other hand, it is now clear that atherosclerosis is a chronic inflammatory disease and oxidized LDL is a key factor in the process of plaque inflammation. High-sensitive CRP (hs-CRP) may be thus used for the predictor of CHD, but it can not be available for patients accompanied with other inflammatory diseases. More recently, it is reported that serum LOX-1 is a possible predictor for CHD. These predictors are clinically useful and more sensitive biomarkers for atherosclerosis may be available in the future.
  • 臨床検査への応用の可能性
    日野田 裕治
    2004 年 48 巻 4 号 p. 147-150
    発行日: 2004/12/15
    公開日: 2009/03/31
    ジャーナル フリー
    It has been shown that the matrix metalloproteinase (MMP)-1 promoter polymorphism 1G/2G is associated with an increased risk of developing various cancers including renal cell carcinoma (RCC), and is in linkage disequilibrium (LD) with the MMP-3 promoter polymorphism 5A/6A. However, the relationship between the MMP-3 5A/6A polymorphism and susceptibility to cancer remains ambiguous. In this study, we genotyped eight polymorphisms over the region of the MMP-1 and MMP-3 genes in 177 healthy subjects, and explored the relationships between RCC and these polymorphisms or haplotypes in 156 cases and 230 age- and gender-matched controls. There were three polymorphisms that showed stronger LD with the MMP-1 1G/2G than with the MMP-3 promoter 5A/6A variant. One of these three polymorphisms was found to be present in the second exon of the MMP-3 gene and to cause an amino acid change, Glu45Lys (G/A). When the genotype distribution of Glu45Lys was compared between RCC patients and controls, the frequency of the G/G genotype was significantly higher in the patients (age- and gender-adjusted odds ratio [OR]=1.81). A significant increase in the frequency of the 2G/2G genotype of MMP-1 1G/2G polymorphism was also observed in the patients (age- and gender-adjusted OR=1.86). The frequency of the 2G-G haplotype of MMP-1 1G/2G and MMP-3 Glu45Lys polymorphisms was significantly higher in the patients compared to controls (crude OR=1.95, CI=1.31-2.91). These findings suggest that a haplotype of MMP-1 and MMP-3 variants may be associated with the risk of developing RCC.
  • 宮地 勇人
    2004 年 48 巻 4 号 p. 151-157
    発行日: 2004/12/15
    公開日: 2009/03/31
    ジャーナル フリー
    Advances in molecular biotechnologies and elucidation of molecular etiology of diseases in combination have facilitated laboratory uses of the molecular diagnostic tests. Uses of the molecular diagnostic tests have been essential in performing medical practice of infectious, neoplastic as well as genetic diseases. Automated systems have been developed for amplification and detection, and lately for extraction, allowing improvement of not only assay efficiency but also quality control of the tests. The information on the genome sequences as the outcome of human genome project has been studied to elucidate functions of genes and proteins and clinical significance of nucleic acid sequences. There has been further technological innovations for post-genomics such as expression profiling using DNA microarray, proteomics, and single nucleotide polymorphisms analysis, in conjunction with bioinformatics. Such emerging technologies will continue to be investigated for usage of the molecular diagnostic tests for therapeutic and preventive health care.
  • 富永 真琴
    2004 年 48 巻 4 号 p. 159-162
    発行日: 2004/12/15
    公開日: 2009/03/31
    ジャーナル フリー
    One of most important reasons of the advancement of treatment of diabetes mellitus after the 1980s was the clinical application of hemoglobin A1c (HbA1c). However, HbA1c is not the name of a substance, but the name of one fraction of HPLC, so standardization has been difficult. In Japan, by using the primary calibrators, Lot 1 and Lot 2, standardization has been achieved and maintained. The international standardization of the measurement of HbA1c will be completed in the near future according to the method proposed by the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC). In order to avoid expected confusions, the Japan Diabetes Society (JDS) and the Japan Society of Clinical Chemistry (JSCC) committees propose A1c-ISP (International Standardized Percent) as the new test name.
  • 糖鎖結合位置及び結合糖鎖の解析
    伊藤 さつき, 原園 景, 川崎 ナナ, 橋井 則貴, 松石 紫, 川西 徹, 早川 堯夫
    2004 年 48 巻 4 号 p. 163-168
    発行日: 2004/12/15
    公開日: 2009/03/31
    ジャーナル フリー
    LC/MS/MSは, アミノ酸配列情報に加え, 糖鎖構造に関する情報についても得ることができ, 糖ペプチドの解析にも有用である. QqTOF-MSを用いたLC/MS/MSは, 糖ペプチドのピークを特定し, ペプチドを同定し, 結合糖鎖構造に関する情報も得ることができる. 本稿では, 糖ペプチドの解析例として, APF及び電気泳動で分離されたGPIアンカー型タンパク質の解析例を示す.
  • 小林 直之, Gerherd Weber
    2004 年 48 巻 4 号 p. 169-174
    発行日: 2004/12/15
    公開日: 2009/03/31
    ジャーナル フリー
    The principle of free-flow electrophoresis (FFE) was first introduced by Barrolier (1958) and Hannig (1961). FFE provides a liquid-based separation in three different operating modes: zone electrophoresis-separation of particles (cells, organelles) due to their electrophoretic mobility, isotachphoresis-separation of proteins and peptides in pH step gradient and isoelectric focusing-separation of proteins and peptides due to their isoelectric point. The key feature of FFE technology is as follows. (i) The separation is performed continuously and enables us to obtain as much as hundreds of milligrams or even gram amounts pure substances. (ii) the separation is performed in a thin aqueous film without gels and enables us to collection of matrix-free fraction with high reproducibility. Therefore, FFE technology ensures that the separated samples are compatible with all downstream concentration procedures (e.g. ultrafiltration), whose enrichment allows to visualize less abundant proteins for subsequent 2-DE analysis and separate poor soluble proteins (e.g. membrane proteins) for subsequent SDS-PAGE. Moreover, FFE can be coupled with such analytical methods as liquid chromatography/mass spectrometry. In the field of proteomics, FFE is a highly versatile technology to support key applications due to prefractionation of samples.
  • 田澤 英克, 坂口 和子, 鈴木 潤
    2004 年 48 巻 4 号 p. 175-179
    発行日: 2004/12/15
    公開日: 2009/03/31
    ジャーナル フリー
    日常的な分析法では試料の微量化, および短時間でしかも多数の試料の同時分析が要求されている. ミクロ2次元ポリアクリルアミドゲル電気泳動法 (M2D-PAGE) は2次元電気泳動法のゲルサイズのミクロ化により, 試料量を微量にし, さらに, 泳動時間を短縮するために考案された.
    ここに述べる方法は, M2D-PAGEをさらに改善するものであり, M2D-PAGEのゲルの薄層化により熱発散効率を改善し, 泳動時間, 染色, 脱色時間の短縮, ならびに少試料化を目指した.
    ここでは, M2D-PAGE 1サイクルを約30分間で終了する方法を確立した. さらに, クマシーブリリアントブルー染色でM2D-PAGEの1/12の試料量である0.1μLにより, 従来法と同数のタンパク質スポットを検出し, 加えて, 銀染色では試料量1nLによりスポットの検出が可能となった.
  • Brandon C. Jones, Newton P. Hilliard
    2004 年 48 巻 4 号 p. 181-184
    発行日: 2004/12/15
    公開日: 2009/03/31
    ジャーナル フリー
    Oxidation of sulfur by microorganisms is a topic of interest for a number of researchers worldwide. Literature reports indicate that several different pathways for sulfur oxidation may be present within a single organism. In order to discriminate between activities within these pathways, methods must be available which allow discrimination between specific sulfur oxidizing activities. We describe herein a general method of increasing contrast of ferricyanide reducing zymograms and simultaneously fixing gels for storage.
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