ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Publication Date: 2009-03-03
    Description: Reprogramming of somatic cells to pluripotency, thereby creating induced pluripotent stem (iPS) cells, promises to transform regenerative medicine. Most instances of direct reprogramming have been achieved by forced expression of defined factors using multiple viral vectors. However, such iPS cells contain a large number of viral vector integrations, any one of which could cause unpredictable genetic dysfunction. Whereas c-Myc is dispensable for reprogramming, complete elimination of the other exogenous factors is also desired because ectopic expression of either Oct4 (also known as Pou5f1) or Klf4 can induce dysplasia. Two transient transfection-reprogramming methods have been published to address this issue. However, the efficiency of both approaches is extremely low, and neither has been applied successfully to human cells so far. Here we show that non-viral transfection of a single multiprotein expression vector, which comprises the coding sequences of c-Myc, Klf4, Oct4 and Sox2 linked with 2A peptides, can reprogram both mouse and human fibroblasts. Moreover, the transgene can be removed once reprogramming has been achieved. iPS cells produced with this non-viral vector show robust expression of pluripotency markers, indicating a reprogrammed state confirmed functionally by in vitro differentiation assays and formation of adult chimaeric mice. When the single-vector reprogramming system was combined with a piggyBac transposon, we succeeded in establishing reprogrammed human cell lines from embryonic fibroblasts with robust expression of pluripotency markers. This system minimizes genome modification in iPS cells and enables complete elimination of exogenous reprogramming factors, efficiently providing iPS cells that are applicable to regenerative medicine, drug screening and the establishment of disease models.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2667910/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2667910/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Kaji, Keisuke -- Norrby, Katherine -- Paca, Agnieszka -- Mileikovsky, Maria -- Mohseni, Paria -- Woltjen, Knut -- G0700672/Medical Research Council/United Kingdom -- G0700672(82649)/Medical Research Council/United Kingdom -- Biotechnology and Biological Sciences Research Council/United Kingdom -- Medical Research Council/United Kingdom -- England -- Nature. 2009 Apr 9;458(7239):771-5. doi: 10.1038/nature07864. Epub 2009 Mar 1.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉MRC Centre for Regenerative Medicine, Institute for Stem Cell Research, University of Edinburgh, Edinburgh EH9 3JQ, UK. keisuke.kaji@ed.ac.uk〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/19252477" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; Biomarkers/analysis ; Cell Line ; Cells, Cultured ; Cellular Reprogramming/*genetics ; Fibroblasts/cytology ; Gene Expression Profiling ; Genetic Vectors/*genetics ; Humans ; Mice ; Pluripotent Stem Cells/*cytology/metabolism ; Transfection/*methods ; Transgenes/genetics
    Print ISSN: 0028-0836
    Electronic ISSN: 1476-4687
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Publication Date: 2009-03-03
    Description: Transgenic expression of just four defined transcription factors (c-Myc, Klf4, Oct4 and Sox2) is sufficient to reprogram somatic cells to a pluripotent state. The resulting induced pluripotent stem (iPS) cells resemble embryonic stem cells in their properties and potential to differentiate into a spectrum of adult cell types. Current reprogramming strategies involve retroviral, lentiviral, adenoviral and plasmid transfection to deliver reprogramming factor transgenes. Although the latter two methods are transient and minimize the potential for insertion mutagenesis, they are currently limited by diminished reprogramming efficiencies. piggyBac (PB) transposition is host-factor independent, and has recently been demonstrated to be functional in various human and mouse cell lines. The PB transposon/transposase system requires only the inverted terminal repeats flanking a transgene and transient expression of the transposase enzyme to catalyse insertion or excision events. Here we demonstrate successful and efficient reprogramming of murine and human embryonic fibroblasts using doxycycline-inducible transcription factors delivered by PB transposition. Stable iPS cells thus generated express characteristic pluripotency markers and succeed in a series of rigorous differentiation assays. By taking advantage of the natural propensity of the PB system for seamless excision, we show that the individual PB insertions can be removed from established iPS cell lines, providing an invaluable tool for discovery. In addition, we have demonstrated the traceless removal of reprogramming factors joined with viral 2A sequences delivered by a single transposon from murine iPS lines. We anticipate that the unique properties of this virus-independent simplification of iPS cell production will accelerate this field further towards full exploration of the reprogramming process and future cell-based therapies.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3758996/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3758996/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Woltjen, Knut -- Michael, Iacovos P -- Mohseni, Paria -- Desai, Ridham -- Mileikovsky, Maria -- Hamalainen, Riikka -- Cowling, Rebecca -- Wang, Wei -- Liu, Pentao -- Gertsenstein, Marina -- Kaji, Keisuke -- Sung, Hoon-Ki -- Nagy, Andras -- 077186/Wellcome Trust/United Kingdom -- G0700672/Medical Research Council/United Kingdom -- Wellcome Trust/United Kingdom -- England -- Nature. 2009 Apr 9;458(7239):766-70. doi: 10.1038/nature07863. Epub 2009 Mar 1.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, Ontario M5G 1X5, Canada.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/19252478" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; *Cell Differentiation ; Cell Line ; Cells, Cultured ; Cellular Reprogramming/*genetics ; DNA Transposable Elements ; Fibroblasts/*cytology/*physiology/virology ; Gene Order ; Gene Transfer Techniques ; Genetic Vectors/*genetics ; Humans ; Mice ; Mice, Nude ; Pluripotent Stem Cells/*physiology ; Sequence Alignment ; Transcription Factors/genetics ; Transgenes/genetics
    Print ISSN: 0028-0836
    Electronic ISSN: 1476-4687
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Publication Date: 1992-09-04
    Description: Coronary collateral vessels reduce damage to ischemic myocardium after coronary obstruction. Factors that stimulate collateral formation are expected to have ameliorating effects on myocardial infarction. In a canine experimental myocardial infarct model, intracoronary injection of basic fibroblast growth factor (bFGF) improved cardiac systolic function and reduced infarct size. Treatment with bFGF increased the number of arterioles and capillaries in the infarct. Thus, the angiogenic action of bFGF might lead to a reduction in infarct size. The application of bFGF might bring about a therapeutic modality for the salvage of infarcted myocardium.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Yanagisawa-Miwa, A -- Uchida, Y -- Nakamura, F -- Tomaru, T -- Kido, H -- Kamijo, T -- Sugimoto, T -- Kaji, K -- Utsuyama, M -- Kurashima, C -- New York, N.Y. -- Science. 1992 Sep 4;257(5075):1401-3.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Second Department of Internal Medicine, Faculty of Medicine, University of Tokyo, Japan.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/1382313" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; Arterioles/pathology ; Capillaries/pathology ; Cell Division ; Coronary Angiography ; Coronary Vessels/pathology ; Dogs ; Endothelium, Vascular/pathology ; Fibroblast Growth Factor 2/administration & dosage/*therapeutic use ; Heart Ventricles/pathology ; Muscle, Smooth, Vascular/pathology ; Myocardial Infarction/*drug therapy/pathology ; Neovascularization, Pathologic ; Organ Size
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    Publication Date: 2013-06-04
    Description: The generation of induced pluripotent stem (iPS) cells presents a challenge to normal developmental processes. The low efficiency and heterogeneity of most methods have hindered understanding of the precise molecular mechanisms promoting, and roadblocks preventing, efficient reprogramming. Although several intermediate populations have been described, it has proved difficult to characterize the rare, asynchronous transition from these intermediate stages to iPS cells. The rapid expansion of minor reprogrammed cells in the heterogeneous population can also obscure investigation of relevant transition processes. Understanding the biological mechanisms essential for successful iPS cell generation requires both accurate capture of cells undergoing the reprogramming process and identification of the associated global gene expression changes. Here we demonstrate that in mouse embryonic fibroblasts, reprogramming follows an orderly sequence of stage transitions, marked by changes in the cell-surface markers CD44 and ICAM1, and a Nanog-enhanced green fluorescent protein (Nanog-eGFP) reporter. RNA-sequencing analysis of these populations demonstrates two waves of pluripotency gene upregulation, and unexpectedly, transient upregulation of several epidermis-related genes, demonstrating that reprogramming is not simply the reversal of the normal developmental processes. This novel high-resolution analysis enables the construction of a detailed reprogramming route map, and the improved understanding of the reprogramming process will lead to new reprogramming strategies.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3743022/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3743022/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉O'Malley, James -- Skylaki, Stavroula -- Iwabuchi, Kumiko A -- Chantzoura, Eleni -- Ruetz, Tyson -- Johnsson, Anna -- Tomlinson, Simon R -- Linnarsson, Sten -- Kaji, Keisuke -- 261075/European Research Council/International -- Medical Research Council/United Kingdom -- England -- Nature. 2013 Jul 4;499(7456):88-91. doi: 10.1038/nature12243. Epub 2013 Jun 2.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉MRC Centre for Regenerative Medicine, University of Edinburgh, Edinburgh BioQuarter, 5 Little France Drive, Edinburgh EH16 4UU, UK.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/23728301" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; Antigens, CD44/genetics/*metabolism ; Biomarkers/analysis/metabolism ; Cellular Reprogramming/genetics/*physiology ; Epidermis/metabolism ; Fibroblasts ; Flow Cytometry ; Gene Expression Profiling ; Genes, Reporter ; Induced Pluripotent Stem Cells/*cytology/*metabolism ; Intercellular Adhesion Molecule-1/genetics/*metabolism ; Mice ; Sequence Analysis, RNA ; Single-Cell Analysis ; Up-Regulation/genetics
    Print ISSN: 0028-0836
    Electronic ISSN: 1476-4687
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 95 (1991), S. 5332-5340 
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: In order to investigate low-energy excitations below 10 meV, inelastic neutron-scattering measurements have been carried out on various organic amorphous polymers at 10 and 50 K and three inorganic glasses at 150 and 295 K. It was found that a broad excitation peak is observed for all amorphous materials in the ω range of 1.5–4.0 meV irrespective of different chemical structures. On the other hand, highly crystalline polyethylene with a degree of crystallinity 0.96 shows no such broad peak, indicating that the low-energy excitation is characteristic of amorphous materials. We have employed an asymmetric double-well potential as a common origin for the low-energy excitation in amorphous materials and analyzed the results of amorphous polyisobutylene to confirm validity of this model and alternatively to determine parameters of the potential. Analysis of the temperature dependence of the inelastic-scattering intensity of the low-energy excitation leads to a concept of phonon-assisted tunneling in the asymmetric double-well potential.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 105 (1996), S. 4342-4349 
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: We have studied the glass transition dynamics of trans-1,4-chloroprene from microscopic view points using a quasielastic neutron scattering technique in a time range of ∼4×10−13 to ∼4×10−10 s. It was found that the so-called fast process of picosecond order appears at around the Vogel–Fulcher temperature T0, similarly to cis-1,4-polybutadiene having no large side groups [J. Chem. Phys. 98, 8262 (1993)]. It is considered that the onset temperature at around T0 must be characteristic to polymers having no large side groups or no large internal degrees of freedom. In addition to the fast process, the slow process of subnanosecond order sets in at around the glass transition temperature Tg and the activation energy of the relaxation time was found to be ∼2.5 kcal/mol. The nature of the slow process is discussed in terms of conformational transition near Tg. © 1996 American Institute of Physics.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 104 (1996), S. 3841-3850 
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The dynamics of atactic polystyrene (PS) has been studied by a quasielastic neutron scattering technique in a temperature range of 21–475 K covering the glass transition temperature Tg (=373 K). The so-called fast process in picosecond order is observed similarly to other glass-forming materials in supercooled states so far reported. However, the onset temperature of the fast process is ∼170 K below Tg in PS, which is far below Tg in contrast to the previous observations. This result implies that the fast process is not necessarily the β process predicted by the recently noted mode coupling theory. By comparing the result of hydrogenated PS with that of partially deuterated polystyrene (PS-d5) where only phenyl rings were preferentially deuterated, the origin of the fast process occurring far below Tg has been assigned to librational motion of phenyl rings, which is coupled with main chain motion near Tg. Analysis of the spectra by curve fit has suggested that the nature of the fast process changes at a temperature ∼30 K above Tg. This change also involves the appearance of a slow relaxation process in the energy range of several tens μeV. The origin of the slow process is discussed in terms of conformational transitions of the main chain. © 1996 American Institute of Physics.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    ISSN: 1520-5835
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    ISSN: 1520-5835
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    ISSN: 1520-5835
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...