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P08-04 Mutagenicity testing of alkenylbenzenes: need for refined approaches due to sulfotransferase-mediated bioactivation. Toxicol Lett 2022. [DOI: 10.1016/j.toxlet.2022.07.403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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2
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Interpretierbares maschinelles Lernen in der Diagnostik von Verkalkungen in der Brust in der Cone-beam Brust CT und digitalen Vollfeldmammographie. ROFO-FORTSCHR RONTG 2022. [DOI: 10.1055/s-0042-1749851] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Impact of medical imaging on the epigenome - low-dose exposure in the course of computed tomography does not induce detectable changes of DNA-methylation profiles in peripheral blood cells. Int J Radiat Biol 2021; 98:980-985. [PMID: 34779695 DOI: 10.1080/09553002.2021.2004329] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
BACKGROUND Computed tomography (CT) is a main contributor to artificial low-dose exposure. Understanding the biological effects induced by CT exposure and their dependency on the characteristics of photon spectra is essential for knowledge-driven risk assessment. In a previous gene expression study, we have identified upregulation of AEN, BAX, DDB2, EDA2R and FDXR after ex vivo exposure with single-energy CT and dual-energy CT (DECT). In this study, we focused on CT-induced changes of DNA methylation. This epigenetic modification of DNA is a central regulator of gene expression and instrumental in preserving genome integrity. Previous studies reported focal hypermethylation and global hypomethylation after exposure with doses above 100 mSv, however, the effect of low dose exposure on DNA methylation is hardly explored. MATERIALS AND METHODS DNA was isolated from peripheral blood of three healthy individuals 6 h after ex vivo exposition to single-energy (80 kV and 150 kV) and DECT (80 kV/Sn150 kV) with a calculated effective dose of 7.0 ± 0.08 mSv. The experimental setting was identical to the one used in our previous gene expression study enabling a direct comparison of gene expression results with changes of DNA methylation identified in this study. DNA methylation was analyzed by high-throughput sequencing of bisulfite-treated DNA targeted methylation sequencing. RESULTS Unsupervised hierarchical clustering based on DNA methylation profiles of all samples created three distinct clusters. Formation of these three clusters was solely determined by the origin of samples, indicating the absence of prominent irradiation-associated changes of DNA methylation. In line with this observation, inter-individual comparison of non-irradiated samples revealed 1163, 1224 and 4550 significant differentially methylated regions (DMRs), respectively, whereas the pairwise comparison of irradiated and non-irradiated samples failed to identify irradiation-induced DMRs in any of the three probands. This even applied to the genomic regions harboring AEN, BAX, DDB2, EDA2R and FDXR, the five genes known to be upregulated by CT exposure. CONCLUSIONS CT exposure with various photon spectra did not result in detectable changes of DNA methylation. However, minor effects in a subpopulation of irradiated cells cannot be ruled out. Thus, future studies with extended observation intervals are needed to investigate DNA methylation changes that are induced by indirect effects at later points of time or become detectable by clonal expansion of affected cells. Moreover, our data suggest that DNA methylation analysis is less sensitive in detecting immediate effects of low-dose irradiation when compared to gene expression analysis.
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Gene expression changes and DNA damage after ex vivo exposure of peripheral blood cells to various CT photon spectra. Sci Rep 2021; 11:12060. [PMID: 34103547 PMCID: PMC8187728 DOI: 10.1038/s41598-021-91023-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Accepted: 05/13/2021] [Indexed: 11/09/2022] Open
Abstract
Dual-energy CT provides enhanced diagnostic power with similar or even reduced radiation dose as compared to single-energy CT. Its principle is based on the distinct physical properties of low and high energetic photons, which, however, may also affect the biological effectiveness and hence the extent of CT-induced cellular damage. Therefore, a comparative analysis of biological effectiveness of dual- and single-energy CT scans with focus on early gene regulation and frequency of radiation-induced DNA double strand breaks (DSBs) was performed. Blood samples from three healthy individuals were irradiated ex vivo with single-energy (80 kV and 150 kV) and dual-energy tube voltages (80 kV/Sn150kV) employing a modern dual source CT scanner resulting in Volume Computed Tomography Dose Index (CTDIvol) of 15.79-18.26 mGy and dose length product (DLP) of 606.7-613.8 mGy*cm. Non-irradiated samples served as a control. Differential gene expression in peripheral blood mononuclear cells was analyzed 6 h after irradiation using whole transcriptome sequencing. DSB frequency was studied by 53BP1 + γH2AX co-immunostaining and microscopic evaluation of their focal accumulation at DSBs. Neither the analysis of gene expression nor DSB frequency provided any evidence for significantly increased biological effectiveness of dual-energy CT in comparison to samples irradiated with particular single-energy CT spectra. Relative to control, irradiated samples were characterized by a significantly higher rate of DSBs (p < 0.001) and the shared upregulation of five genes, AEN, BAX, DDB2, FDXR and EDA2R, which have already been suggested as radiation-induced biomarkers in previous studies. Despite steadily decreasing doses, CT diagnostics remain a genotoxic stressor with impact on gene regulation and DNA integrity. However, no evidence was found that varying X-ray spectra of CT impact the extent of cellular damage.
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Identification of physiologically relevant EWS-FLI1 target genes in Ewing sarcoma via CRISPRa screening. Eur J Cancer 2020. [DOI: 10.1016/s0959-8049(20)31129-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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6
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Energieeffizienz in der Prozessindustrie – Technologieoptionen des Forschungsnetzwerks Energie in Industrie und Gewerbe. CHEM-ING-TECH 2020. [DOI: 10.1002/cite.202055180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Abstract
Acute right heart failure is often overlooked as a cause of cardiopulmonary insufficiency. The various pathologies underlying right heart failure at the level of afterload, preload and contractility, make rapid, targeted diagnostics necessary. In addition to clinical symptoms and laboratory chemical parameters, echocardiography in particular is relevant for making a diagnosis. Symptomatic treatment of the endangered patient is essential. The focus is on a reduction of right ventricular pressure and afterload, a correction of systemic hypotension and positive inotropic support of the right ventricle. Mechanical organ replacement and support procedures are increasingly being used in the case of persistent right heart failure and expand the possibilities for treatment. Decisive for the prognosis is a causal treatment adapted to the underlying triggering disease.
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Influence of the charge of the complex unit on the SCO properties in pyrazolyl-pyridinyl-benzimidazole based Fe(II) complexes. Polyhedron 2017. [DOI: 10.1016/j.poly.2017.06.035] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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10
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Daily changes of individual gait patterns identified by means of support vector machines. Gait Posture 2016; 49:309-314. [PMID: 27479216 DOI: 10.1016/j.gaitpost.2016.07.073] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/19/2015] [Revised: 07/19/2016] [Accepted: 07/21/2016] [Indexed: 02/02/2023]
Abstract
Despite the common knowledge about the individual character of human gait patterns and about their non-repeatability, little is known about their stability, their interactions and their changes over time. Variations of gait patterns are typically described as random deviations around a stable mean curve derived from groups, which appear due to noise or experimental insufficiencies. The purpose of this study is to examine the nature of intrinsic inter-session variability in more detail by proving separable characteristics of gait patterns between individuals as well as within individuals in repeated measurement sessions. Eight healthy subjects performed 15 gait trials at a self-selected speed on eight days within two weeks. For each trial, the time-continuous ground reaction forces and lower body kinematics were quantified. A total of 960 gait patterns were analysed by means of support vector machines and the coefficient of multiple correlation. The results emphasise the remarkable amount of individual characteristics in human gait. Support vector machines results showed an error-free assignment of gait patterns to the corresponding individual. Thus, differences in gait patterns between individuals seem to be persistent over two weeks. Within the range of individual gait patterns, day specific characteristics could be distinguished by classification rates of 97.3% and 59.5% for the eight-day classification of lower body joint angles and ground reaction forces, respectively. Hence, gait patterns can be assumed not to be constant over time and rather exhibit discernible daily changes within previously stated good repeatability. Advantages for more individual and situational diagnoses or therapy are identified.
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11
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Photothermal method for absorption measurements in anisotropic crystals. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2016; 87:023904. [PMID: 26931863 DOI: 10.1063/1.4941662] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
A measurement system for quantitative determination of both surface and bulk contributions to the photo-thermal absorption has been extended to anisotropic optical media. It bases upon a highly sensitive Hartmann-Shack wavefront sensor, accomplishing precise on-line monitoring of wavefront deformations of a collimated test beam transmitted perpendicularly through the laser-irradiated side of a cuboid sample. Caused by the temperature dependence of the refractive index as well as thermal expansion, the initially plane wavefront of the test beam is distorted. Sign and magnitude depend on index change and expansion. By comparison with thermal theory, a calibration of the measurement is possible, yielding a quantitative absolute measure of bulk and surface absorption losses from the transient wavefront distortion. Results for KTP and BBO single crystals are presented.
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Gefährdungsanalyse – aus Sicht des UBA. DAS GESUNDHEITSWESEN 2014. [DOI: 10.1055/s-0034-1371608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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13
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Analysis of the oligomeric state and transactivation potential of TAp73α. Cell Death Differ 2013; 20:1008-16. [PMID: 23538419 DOI: 10.1038/cdd.2013.23] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2013] [Revised: 02/21/2013] [Accepted: 02/21/2013] [Indexed: 11/09/2022] Open
Abstract
The proteins p73 and p63 are members of the p53 protein family and are involved in important developmental processes. Their high sequence identity with the tumor suppressor p53 has suggested that they act as tumor suppressors as well. While p63 has a crucial role in the maintenance of epithelial stem cells and in the quality control of oocytes without a clear role as a tumor suppressor, p73's tumor suppressor activity is well documented. In a recent study we have shown that the transcriptional activity of TAp63α, the isoform responsible for the quality control in oocytes, is regulated by its oligomeric state. The protein forms an inactive, dimeric and compact conformation in resting oocytes, while the detection of DNA damage leads to the formation of an active, tetrameric and open conformation. p73 shows a high sequence identity to p63, including those domains that are crucial in stabilizing its inactive state, thus suggesting that p73's activity might be regulated by its oligomeric state as well. Here, we have investigated the oligomeric state of TAp73α by size exclusion chromatography and detailed domain interaction mapping, and show that in contrast to p63, TAp73α is a constitutive open tetramer. However, its transactivation potential depends on the cellular background and the promoter context. These results imply that the regulation of p73's transcriptional activity might be more closely related to p53 than to p63.
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Enabling the cryopreservation of parathyroid glands for hospitals without biobank. Exp Clin Endocrinol Diabetes 2013. [DOI: 10.1055/s-0033-1336710] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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15
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Time-resolved investigation of nanometer scale deformations induced by a high flux x-ray beam. OPTICS EXPRESS 2011; 19:15516-15524. [PMID: 21934914 DOI: 10.1364/oe.19.015516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We present results of a time-resolved pump-probe experiment where a Si sample was exposed to an intense 15 keV beam and its surface monitored by measuring the wavefront deformation of a reflected optical laser probe beam. By reconstructing and back propagating the wavefront, the deformed surface can be retrieved for each time step. The dynamics of the heat bump, build-up and relaxation, is followed with a spatial resolution in the nanometer range. The results are interpreted taking into account results of finite element method simulations. Due to its robustness and simplicity this method should find further developments at new x-ray light sources (FEL) or be used to gain understanding on thermo-dynamical behavior of highly excited materials.
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Abstract
Atmospheric plasma jets are being intensively studied with respect to potential applications in medicine. The aim of this in vitro study was to test a microwave-powered non-thermal atmospheric plasma jet for its antimicrobial efficacy against adherent oral micro-organisms. Agar plates and dentin slices were inoculated with 6 log(10) c.f.u. cm(-2) of Lactobacillus casei, Streptococcus mutans and Candida albicans, with Escherichia coli as a control. Areas of 1 cm(2) on the agar plates or the complete dentin slices were irradiated with a helium plasma jet for 0.3, 0.6 or 0.9 s mm(-2), respectively. The agar plates were incubated at 37 degrees C, and dentin slices were vortexed in liquid media and suspensions were placed on agar plates. The killing efficacy of the plasma jet was assessed by counting the number of c.f.u. on the irradiated areas of the agar plates, as well as by determination of the number of c.f.u. recovered from dentin slices. A microbe-killing effect was found on the irradiated parts of the agar plates for L. casei, S. mutans, C. albicans and E. coli. The plasma-jet treatment reduced the c.f.u. by 3-4 log(10) intervals on the dentin slices in comparison to recovery rates from untreated controls. The microbe-killing effect was correlated with increasing irradiation times. Thus, non-thermal atmospheric plasma jets could be used for the disinfection of dental surfaces.
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Fluiddynamische Einflüsse bei der Verarbeitung nanoskaliger Partikelsysteme. CHEM-ING-TECH 2009. [DOI: 10.1002/cite.200950242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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18
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The kinesin I family member KIF5C is a novel substrate for protein kinase CK2. Biochem Biophys Res Commun 2008; 375:179-83. [DOI: 10.1016/j.bbrc.2008.07.107] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2008] [Accepted: 07/23/2008] [Indexed: 11/28/2022]
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21
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Einflüsse auf die elektroosmotische Durchströmung von nanoporösen Haufwerken. CHEM-ING-TECH 2007. [DOI: 10.1002/cite.200600085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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22
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23
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Der Erwerb der Wortproduktionskonsequenz bei Zweijährigen: ein Mittel zur Früherkennung von Aussprachestörungen? SPRACHE-STIMME-GEHOR 2006. [DOI: 10.1055/s-2006-951757] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Wave microcarrier cultivation of MDCK cells for influenza virus production in serum containing and serum-free media. Vaccine 2006; 24:6074-87. [PMID: 16781022 DOI: 10.1016/j.vaccine.2006.05.023] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2006] [Revised: 05/09/2006] [Accepted: 05/16/2006] [Indexed: 02/06/2023]
Abstract
A process for equine influenza virus vaccine production using a microcarrier system (Cytodex 1) in a 2 L Wave bioreactor is described. Growth of Madin Darby canine kidney (MDCK) cells in serum containing GMEM medium (SC) is compared to growth in serum-free Ex-Cell MDCK medium (SF) without washing steps and medium exchange before infection. Cultivations with microcarrier concentrations of 2 and 4 g/L for both media are shown. Metabolic data from carbon and amino acid metabolism are discussed. Additionally, in roller bottle experiments the influence of multiplicity of infection (moi) and trypsin concentration on the HA value was investigated. Analysis of HA and TCID(50) at 37 degrees C showed a stable HA of maximum 2.6 log HA/100 microL for 2 weeks. Peak TCID(50) titers of 10(7.7) viruses/mL were achieved 20h post infection, but infectivity was below detection limit after 150 h. Cell attachment onto microcarriers under serum-free conditions was improved by Ca(2+) addition and by cell harvesting without trypsin using only an EDTA/PBS solution. For the wave cultivation maximum virus titers of 2.3-2.6 log HA units/100 microL were reached from infection with a moi of 0.05. However, in SF medium pH dropped to less than pH 6.8 which resulted in lower HA titers of 1.7 log HA units/100 microL. For the higher microcarrier concentration (4 g/L) medium exchange steps (500 mL) were needed for both media. Omission of the washing step and medium exchange before infection in SF medium clearly simplified the influenza production process; however, for higher virus yields a better pH control of the wave bioreactor would be required. Higher cell densities (2.8 x 10(6) cells/mL for 2 g/L microcarrier) and better attachment compared to stirred tank bioreactors showed, that the wave bioreactor is a good alternative to stirred tank processes for expanding production capacities in case of a pandemic.
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25
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Distinction between Electrostatic and Electrokinetic Effects on the Permeability of Colloidal Packed Beds. Chem Eng Technol 2005. [DOI: 10.1002/ceat.200500079] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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26
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[Fusion inhibitor enfuvirtidE. Continuous virologic and immunologic response]. MMW Fortschr Med 2005; 147 Spec No 1:31. [PMID: 16385869] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
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The in vivo form of the murine class VI POU protein Emb is larger than that encoded by previously described transcripts. Gene 2004; 333:35-46. [PMID: 15177678 DOI: 10.1016/j.gene.2004.02.047] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2003] [Revised: 11/28/2003] [Accepted: 02/05/2004] [Indexed: 11/25/2022]
Abstract
The class VI POU domain family member known as Emb in the mouse (rat Brn5 or human mPOU/TCFbeta1) is present in vivo as a protein migrating at about 80 kDa on western blots, considerably larger than that predicted (about 42 kDa) from previously cloned coding sequences. By RT-PCR and 5' RACE strategies a full-length Emb sequence, Emb FL, is now identified. Shorter sequences encoding the -COOH terminal, and an -NH(2) terminal isoform, EmbN, were also isolated. Comparisons of Emb coding sequences between species, including the full-length zebra fish, POU(c), are presented, together with a compilation of the multiple transcripts produced by alternative splicing and the presence of different transcriptional start and stop sites, from the Emb gene.
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Steuerung der Durchströmung nanoskaliger Haufwerke. CHEM-ING-TECH 2004. [DOI: 10.1002/cite.200490284] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Genetic aspects of targeted insertion mutagenesis in yeasts. FEMS Microbiol Rev 2004; 28:201-23. [PMID: 15109785 DOI: 10.1016/j.femsre.2003.10.002] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2003] [Revised: 08/20/2003] [Accepted: 10/02/2003] [Indexed: 11/16/2022] Open
Abstract
Targeted insertion mutagenesis is a main molecular tool of yeast science initially applied in Saccharomyces cerevisiae. The method was extended to fission yeast Schizosaccharomyces pombe and to "non-conventional" yeast species, which show specific properties of special interest to both basic and applied research. Consequently, the behaviour of such non-Saccharomyces yeasts is reviewed against the background of the knowledge of targeted insertion mutagenesis in S. cerevisiae. Data of homologous integration efficiencies obtained with circular, ends-in or ends-out vectors in several yeasts are compared. We follow details of targeted insertion mutagenesis in order to recognize possible rate-limiting steps. The route of the vector to the target and possible mechanisms of its integration into chromosomal genes are considered. Specific features of some yeast species are discussed. In addition, similar approaches based on homologous recombination that have been established for the mitochondrial genome of S. cerevisiae are described.
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A novel complex regulates cardiac actin gene expression through interaction of Emb, a class VI POU domain protein, MEF2D, and the histone transacetylase p300. Mol Cell Biol 2004; 24:2944-57. [PMID: 15024082 PMCID: PMC371105 DOI: 10.1128/mcb.24.7.2944-2957.2004] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2002] [Revised: 10/23/2002] [Accepted: 01/06/2004] [Indexed: 11/20/2022] Open
Abstract
Expression of the mouse cardiac actin gene depends on a distal enhancer (-7 kbp) which has been shown, in transgenic mice, to direct expression to embryonic skeletal muscle. The presence of this distal sequence is also associated with reproducible expression of cardiac actin transgenes. In differentiated skeletal muscle cells, activity of the enhancer is driven by an E box, binding MyoD family members, and by a 3' AT-rich sequence which is in the location of a DNase I-hypersensitive site. This sequence does not bind MEF2 proteins, or other known muscle transcription factors, directly. Oct1 and Emb, a class VI POU domain protein, bind to consensus sites on the DNA, and it is the binding of Emb which is important for activity. Emb binds as a major complex with MEF2D and the histone transacetylase p300. The form of Emb present in this complex and as a major form in muscle cell extracts is longer (80 kDa) than that previously described. These results demonstrate the importance of this novel complex in the transcriptional regulation of the cardiac actin gene and suggest a potential role in chromatin remodeling associated with muscle gene activation.
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31
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Quality of life in children with traumatic brain injury--basic issues, assessment, and recommendations. Restor Neurol Neurosci 2003; 20:151-9. [PMID: 12454363] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/27/2023]
Abstract
An international Task Force was convened under the guidance of BMBF Conference so as to review the "State of the art" for measuring quality of life (QoL) in children who have suffered traumatic brain injury (TBI). After expert review of instruments and evaluation of two independent literature reviews this work group established "inclusion criteria" for the review of current tools that could contribute to the measurement of QoL in children with TBI. Six instruments were determined to meet all or most of the criteria required to be used in current clinical practice and research for children with TBI.
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Abstract
Northern blot analysis suggested that the boar epididymis produces closely related counterparts to human epididymal proteins HE1, HE3, HE4, HE5 and HE12. 'Full-length' cloning by nucleic acid and amino acid sequence similarity was achieved by RT-PCR methods in the case of the porcine counterparts of HE3 and HE4, while the homologues of HE5 and HE12, despite their cross-hybridization during Northern blot analysis, have not yet been cloned. The two novel porcine cDNAs were derived from moderately abundant epididymal mRNAs that were 75 and 83% identical to HE3 and HE4 cDNAs, respectively. To emphasize their relationship to the corresponding HEs, they were named Se3 and Se4 cDNAs. Their open reading frames predicted small secretory proteins with 55% (Se3) and 76% (Se4) conserved amino acids. Monospecific antipeptide antibodies to HE secretory proteins identified He3- and HE12-related proteins on Western blots of porcine epididymal fluid and semen. Both Northern and Western analyses indicated that the Se proteins were produced in a regionalized pattern and accumulated in the cauda fluid.
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Erratum to: Systematische Entwicklung eines Messinstruments zur Erfassung der gesundheitsbezogenen Lebensqualität beim polytraumatisierten Patienten. Unfallchirurg 2002. [DOI: 10.1007/s00113-002-0479-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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[Systematic development of a scale for determination of health-related quality of life in multiple trauma patients. The Polytrauma Outcome (POLO) Chart]. Unfallchirurg 2002; 105:413-22. [PMID: 12132202 DOI: 10.1007/s00113-001-0348-5] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Even years after having sustained multiple injuries patients often suffer from its sequelae. These comprise restrictions in physical function, but also pain, social and psychological impairments. Although the Meran Consensus Conference in 1990 defined the contents of "quality of life" (QoL) measures in surgery, still no instrument is available for the valid assessment of all relevant QoL domains in multiple injured patients. This paper describes the systematic development of a modular instrument for the assessment of health related QoL. Within three phases (phase I: generation of items, phase II: item reduction, phase III: pre-testing in 70 multiple injured and control patients) a questionnaire of 57 items was developed, which measures all relevant trauma-related aspects of QoL after acute hospital care. In combination with the Glascow Outcome Scale (GOS), the EUROQOL and the SF-36, the newly developed instrument builds the Polytrauma Outcome Chart (POLO-Chart) which will also be used as "Part E" for outcome assessment within the "Trauma registry" of the German Society for Trauma Surgery. In phase IV, the POLO-Chart will finally be validated in five trauma centres (Celle, Essen, Hanover, Cologne und Munich).
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Development of an inducible pol III transcription system essentially requiring a mutated form of the TATA-binding protein. Nucleic Acids Res 2001; 29:1672-82. [PMID: 11292839 PMCID: PMC31323 DOI: 10.1093/nar/29.8.1672] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
We attempted to devise a transcription system in which a particular DNA sequence of interest could be inducibly expressed under the control of a modified polymerase III (pol III) promoter. Its activation requires a mutated transcription factor not contained endogenously in human cells. We constructed such a promoter by fusing elements of the beta-lactamase gene of Escherichia coli, containing a modified TATA-box and a pol III terminator, to the initiation region of the human U6 gene. This construct functionally resembles a 5'-regulated pol III gene and its transcribed segment can be exchanged for an arbitrary sequence. Its transcription in vitro by pol III requires the same factors as the U6 gene with the major exception that the modified TATA-box of this construct only interacts with a TATA-binding protein (TBP) mutant (TBP-DR2) but not with TBP wild-type (TBPwt). Its transcription therefore requires TBP-DR2 exclusively instead of TBPWT: In order to render the system inducible, we fused the gene coding for TBP-DR2 to a tetracycline control element and stably transfected this new construct into HeLa cells. Induction of such a stable and viable clone with tetracycline resulted in the expression of functional TBP-DR2. This system may conceptually be used in the future to inducibly express an arbitrary DNA sequence in vivo under the control of the above mentioned promoter.
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MESH Headings
- Base Sequence
- Cloning, Molecular
- DNA/genetics
- DNA/metabolism
- DNA Footprinting
- DNA Polymerase III/metabolism
- DNA, Recombinant/genetics
- DNA-Binding Proteins/genetics
- DNA-Binding Proteins/metabolism
- Escherichia coli/genetics
- Genes, Bacterial/genetics
- Genetic Vectors/genetics
- HeLa Cells
- Humans
- Mutation/genetics
- Protein Binding
- RNA, Messenger/analysis
- RNA, Messenger/biosynthesis
- RNA, Messenger/genetics
- RNA, Small Nuclear/genetics
- Substrate Specificity
- TATA Box/genetics
- TATA-Box Binding Protein
- Templates, Genetic
- Terminator Regions, Genetic/genetics
- Tetracycline/pharmacology
- Transcription Factor TFIIIB
- Transcription Factors/genetics
- Transcription Factors/metabolism
- Transcription Factors, TFIII/metabolism
- Transcription, Genetic/drug effects
- Transcriptional Activation/drug effects
- beta-Lactamases/genetics
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36
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A Short and Efficient Synthesis of (S)-1-Boc-2,5-dihydro-1H-pyrrole-2-carboxylic Acid. SYNTHESIS-STUTTGART 2001. [DOI: 10.1055/s-2001-9755] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
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37
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Abstract
We analyzed the effects of domestication on the subdivisions of the cochlear nucleus in the gerbil (Meriones unguiculatus) by comparing their volumes and rostrocaudal extents in laboratory gerbils and in age-matched F1 offspring of gerbils caught in the wild. In addition, soma size was systematically analyzed in the anteroventral cochlear nucleus of both groups. Total cochlear nucleus volume and rostrocaudal extent were not significantly different between groups either for young (postnatal day 9) animals before the onset of hearing or for young 4-month-old animals. However, the dorsal cochlear nucleus was significantly larger and the anteroventral cochlear nucleus was significantly smaller in young adults of the wild strain. Thus the relative proportions of the cochlear nucleus subdivisions differed between the groups. In addition, soma size was significantly larger in the low-frequency portion of the anterovental cochlear nucleus in domesticated gerbils compared to wild gerbils. To our knowledge, this is the first reported instance of a well-defined brain structure (e.g., the antreovental cochlear nucleus) being larger in the domesticated than in the wild form.
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Abstract
Complete manipulation by laser light allows precise and gentle treatment of plant cells, subcellular structures, and even individual DNA molecules. Recently, affordable lasers have become available for the construction of microbeams as well as for optical tweezers. This may generate new interest in these tools for plant biologists. Early experiments, reviewed in this journal, showed that laser supported microinjection of material into plant cells or tissues circumvents mechanical problems encountered in microinjection by fragile glass capillaries. Plant protoplasts could be fused with each other when under microscopical observation, and it was no major problem to generate a triple or quadruple fusion product. In the present paper we review experiments where membrane material was prepared from root hair tips and microgravity was simulated in algae. As many plant cells are transparent, it is possible to work inside living, intact cells. New experiments show that it is possible to release by optical micromanipulation, with high spatial resolutions, intracellular calcium from caged compounds and to study calcium oscillations. An example for avian cardiac tissue is given, but the technique is also suitable for plant cell research. As a more technical tool, optical tweezers can be used to spatially fix subcellular structures otherwise moving inside a cell and thus make them available for investigation with a confocal microscope even when the time for image formation is extended (for example at low fluorescence emission). A molecular biological example is the handling of chromosomes and isolated individual DNA molecules by laser microtools. For example, chromosomes can be cut along complex trajectories, not only perpendicular to their long axis. Single DNA molecules are cut by the laser microbeam and, after coupling such a molecule to a polystrene microbead, are handled in complex geometries. Here, the individual DNA molecules are made visible with a conventional fluorescence microscope by fluorescent dyes such as SYBRGreen. The cutting of a single DNA molecule by molecules of the restriction endonuclease EcoRI can be observed directly, i.e. a type of single molecule restriction analysis is possible. Finally, mechanical properties of individual DNA molecules can be observed directly.
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39
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In vitro differentiation of endothelial cells from AC133-positive progenitor cells. Blood 2000; 95:3106-12. [PMID: 10807776] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023] Open
Abstract
Recent findings support the hypothesis that the CD34(+)-cell population in bone marrow and peripheral blood contains hematopoietic and endothelial progenitor and stem cells. In this study, we report that human AC133(+) cells from granulocyte colony-stimulating factor-mobilized peripheral blood have the capacity to differentiate into endothelial cells (ECs). When cultured in the presence of vascular endothelial growth factor (VEGF) and the novel cytokine stem cell growth factor (SCGF), AC133(+) progenitors generate both adherent and proliferating nonadherent cells. Phenotypic analysis of the cells within the adherent population reveals that the majority display endothelial features, including the expression of KDR, Tie-2, Ulex europaeus agglutinin-1, and von Willebrand factor. Electron microscopic studies of these cells show structures compatible with Weibel-Palade bodies that are found exclusively in vascular endothelium. AC133-derived nonadherent cells give rise to both hematopoietic and endothelial colonies in semisolid medium. On transfer to fresh liquid culture with VEGF and SCGF, nonadherent cells again produce an adherent and a nonadherent population. In mice with severe combined immunodeficiency, AC133-derived cells form new blood vessels in vivo when injected subcutaneously together with A549 lung cancer cells. These data indicate that the AC133(+)-cell population consists of progenitor and stem cells not only with hematopoietic potential but also with the capacity to differentiate into ECs. Whether these hematopoietic and endothelial progenitors develop from a common precursor, the hemangioblast will be studied at the single-cell level.
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40
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Topotecan--a new treatment option in the therapy of brain metastases of lung cancer. FRONTIERS OF RADIATION THERAPY AND ONCOLOGY 1999; 33:354-63. [PMID: 10549507 DOI: 10.1159/000061219] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
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41
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42
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[Difference between gastric mucosal pCO2 and arterio-intramucosal pCO2 during orthotopic liver transplantation]. Wien Klin Wochenschr 1999; 111:555-9. [PMID: 10467642] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
Tonometry is a clinically accepted method to monitor blood flow of the splanchnic region, which is of particular interest in orthotopic liver transplantation (OLT). We investigated the hemodynamic changes and the tonometrically registered perioperative course of the difference between gastric mucosal pCO2 (prCO2) and arterial mucosal CO2 (CO2 gap) in 23 patients undergoing OLT without veno-venous bypass. Gastric mucosal pH (pHi) was additionally calculated. Despite significant changes in systemic hemodynamics during the anhepatic stage and after reperfusion and a significant drop in pHi during anhepacy, the difference between prCO2 and CO2 was constant. These contrasting findings of tonometry, i.e. solely a drop in pHi is, in our opinion, a consequence of the poor metabolic capacity of the liver in the perioperative OLT period, which influenced the calculation of the pHi with the Henderson-Hasselbalch equation. We conclude that, due to methodical problems, calculated pHi is not a reliable indicator of splanchnic blood flow and oxygenation during OLT. We therefore suggest that the prCO2 and the CO2 gap be used to monitor the splanchnic region. These parameters, obtained perioperatively, do not indicate a further reduction in splanchnic oxygenation despite profound changes in systemic hemodynamics during OLT without veno-venous bypass.
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43
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Abstract
Single-molecule studies in the life sciences often deal with observation or spectroscopy. Studies of reactions are rare, and the light microscope has been used for such experiments only occasionally. In an experimental environment, for example, as is required for most nearfield scanning or electron microscopies, it is difficult to study single-molecule reactions of biological relevance. Therefore, we have developed techniques to study single-molecule reactions with classic (nonscanning) farfield light microscopy. The conversion of nicotinamide adenine dinucleotide (NAD+) and lactate to NADH (a reduced form of NAD+), pyruvate, and H+ catalyzed by a few LDH-1 enzyme molecules has been studied in substrate solutions with different viscosity using the NADH autofluorescence. It is even possible to monitor the progress of the reaction by phase-contrast microscopy via scattering or absorption by product molecules. As an example for a single-molecule reaction with a macromolecule as substrate, the handling and enzymatic cutting of fluorescently stained lambda-DNA is studied. In solutions containing 10 mM magnesium and 66 mM potassium ions at pH 7.9, an individual DNA molecule tends to collapse into a globular structure. When moved through an aqueous solution, it becomes stretched by viscosity drag. After stopping the motion, the molecule collapses and the dynamics of this process can be quantified. When a restriction enzyme is present, sequence-specific cutting can be directly observed in the light microscope. The theoretical restriction pattern, as predicted from the sequence of the molecule, can be generated directly under visual inspection.
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A novel group-II intron in the cox1 gene of the fission yeast Schizosaccharomyces pombe is inserted in the same codon as the mobile group-II intron aI2 in the Saccharomyces cerevisiae cox1 homologue. Curr Genet 1999; 35:602-8. [PMID: 10467004 DOI: 10.1007/s002940050458] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
We describe herein a large group-II intron which is inserted in the mitochondrial cox1 gene of the Schizosaccharomyces pombe strain EF2. The intron RNA consists of 2492 nucleotides which can be folded into a secondary structure with all the expected sequence motifs of subgroup-IIA1 introns (Michel et al. 1989). Determination of the exact splice point revealed that the intron is inserted in the same codon, but 1 bp downstream, as the mobile intron aI2 in the Saccharomyces cerevisiae cox1 homologue. A total of nine nucleotide changes was observed around the insertion site of the intron in the cox1 gene of strain EF2 compared with the reference strain ade7-50h(-). Seven of these changes are clustered within the 51 bp upstream of the splice point. Only one sequence deviation was found in the downstream exon. The intron is capable of splicing despite the fact that both the EBS1/IBS1 and the EBS2/IBS2 sequence motifs, thought to be necessary for correct splicing, extend over 5 instead of 6 bp. The maturase, endonuclease and reverse transcriptase domains of the putative protein encoded by the newly described S. pombe group-II intron were not closer to those encoded by the other two, cobI and cox2I, S. pombe group-II introns than to the group-II intron-encoded proteins in Allomyces, Marchantia, Podospora and Saccharomyces.
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45
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Calculations of multicomponent phase equilibria with a new group contribution method. Phys Chem Chem Phys 1999. [DOI: 10.1039/a806724d] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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46
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Abstract
Two Pichia stipitis ADH genes (PsADH1 and PsADH2) were isolated by complementation of a Saccharomyces cerevisiae Adh(-)-mutant. The genes enabled the transformants to grow in the presence of antimycin A on glucose, to use ethanol as sole carbon source and made them sensitive to allylalcohol. The sequences of the genes showed similarities of 70-77% to sequences of ADH genes of Candida albicans, Kluyveromyces lactis, K. marxianus, and S. cerevisiae and about 60% homology to those of Schizosaccharomyces pombe and Aspergillus flavus. Southern hybridization experiments suggested that P. stipitis has only these two ADH genes. Both genes are located on the largest chromosome of P. stipitis. PsADH2 encodes for the ADH activity that is responsible for ethanol formation at oxygen limitation. The gene is regulated at the transcriptional level. Moreover, also in cells grown on ethanol, only PsADH2 transcript was found. PsADH1 transcript was detected under aerobic conditions on fermentable carbon sources.
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47
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Tolerability of high energy transurethral microwave thermotherapy with topical urethral anesthesia: results of a prospective, randomized, single-blinded clinical trial. J Urol 1998; 160:772-6. [PMID: 9720545 DOI: 10.1097/00005392-199809010-00039] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
PURPOSE We determine the tolerability of high energy transurethral microwave thermotherapy with topical urethral anesthesia alone without supplementary systemic sedoanalgesia. MATERIALS AND METHODS A total of 45 patients with symptomatic benign prostatic hyperplasia were randomized to high energy transurethral microwave thermotherapy using either topical urethral anesthesia alone (topical anesthesia group) or topical anesthesia with adjunctive intravenous sedoanalgesia (sedoanalgesia group). Pain was evaluated sequentially by means of a 0 to 10 visual analog scale score. Posttreatment followup included determinations of International Prostate Symptom Score, peak flow rate, post-void residual urine, and quality of life score at 6 and 12 weeks. RESULTS Upon commencement of microwave treatment mean visual analog scale score was 1.3 (95% confidence interval [CI], 1.0 to 1.7) in the sedoanalgesia group and 1.4 (95% CI, 1.0 to 1.9) in the topical anesthesia group. During therapy visual analog scale score increased to a peak at 30 minutes of 2.0 (95% CI, 1.6 to 2.4) and 2.2 (95% CI, 1.7 to 2.6) in the sedoanalgesia and topical anesthesia groups, respectively. Thereafter, visual analog scale score continuously declined, falling to 0.1 (95% CI, 0.0 to 0.2) and 0.2 (95% CI, 0.0 to 0.3) in the 2 respective groups by 1 hour following conclusion of the treatment period. There was no statistically significant difference between the groups in the treatment profile of visual analog scale scores (p = 0.701). Significant posttreatment improvements were demonstrated in International Prostate Symptom Score, peak flow rate, post-void residual urine and quality of life scores but there were no significant differences between the groups in the magnitude of improvement in these outcome measures. CONCLUSIONS High energy transurethral microwave thermotherapy is well tolerated by patients under topical anesthesia alone and, therefore, can be administered in the outpatient setting without potent medications that necessitate intensive patient monitoring, pose risks for side effects and add to treatment costs.
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48
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Mosaic structure of the cox2 gene in the petite negative yeast Schizosaccharomyces pombe: a group II intron is inserted at the same location as the otherwise unrelated group II introns in the mitochondria of higher plants. Gene 1998; 214:101-12. [PMID: 9651494 DOI: 10.1016/s0378-1119(98)00204-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
In contrast to homologous genes in other fungal mitochondrial genomes, the gene encoding subunit 2 of cytochrome oxidase (cox2) in several Schizosaccharomyces pombe strains contains a large group II intron. Its 2436 nucleotides can be folded into a typical group II intron secondary structure, possessing all the expected sequence motifs for subgroup IIA1 (Michel et al., 1989). This intron is remarkable for the following reasons: (i) Five nucleotide changes were observed compared with the continuous form of the cox2 gene in the reference strain 50 at the 3'-exon sequence, but not in the 5'-exon. (ii) One of these changes occurred at the splice point leading to a serine instead of a threonine residue in the deduced cox2 polypeptide. In all cases, the alterations resulted in the replacement of more frequently used codons by rare ones. (iii) Although the intron is able to undergo splicing, the sequence motifs thought to be necessary for interaction between the 5'-exon and the intron during the splicing process (the EBS1/IBS1 as well as the EBS2/IBS2 pairings) are unusual. (iv) The intron is inserted at the same location in the cox2 gene as the otherwise unrelated intron from higher plants.
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49
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Detection of graft nonfunction after liver transplantation by assessment of indocyanine green kinetics. Anesth Analg 1998; 87:34-6. [PMID: 9661541 DOI: 10.1097/00000539-199807000-00008] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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50
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Relocation of urf a from the mitochondrion to the nucleus cures the mitochondrial mutator phenotype in the fission yeast Schizosaccharomyces pombe. MOLECULAR & GENERAL GENETICS : MGG 1998; 258:389-96. [PMID: 9648744 DOI: 10.1007/s004380050746] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
In previous papers we have reported the characterisation of mitochondrial mutator mutants of Schizosaccharomzyces pombe. In contrast to nuclear mutator mutants known from other eucaryotes, this mutator phenotype correlates with mutations in an unassigned open reading frame (urf a) in the mitochondrial genome. Since an efficient biolistic transformation system for fission yeast mitochondria is not yet available, we relocated the mitochondrial urf a gene to the nucleus. As host strain for the ectopic expression, we used the nonsense mutant ana(r)-6, which carries a premature stop codon in the urf a gene. The phenotype of this mutant is characterised by continuous segregation of progeny giving rise to fully respiration competent colonies, colonies that show moderate growth on glycerol and a fraction of colonies that are unable to grow on glycerol. The phenotype of this mutant provides an excellent tool with which to study the effects on the mutator phenotype of ectopic expression of the urf a gene. Since a UGA codon encoding tryptophan is present in the original mitochondrial gene, we constructed two types of expression cassettes containing either the mitochondrial version of the urf a gene (mt-urf a) or a standard genetic code version (nc-urf a; UGA replaced by UGG) fused to the N-terminal import leader sequence of the cox4 gene of Saccharomyces cerevisiae. We show that the expression of the mt-urf a gene in its new location is able to cure, at least in part, the phenotype of mutant ana(r)-6, whereas the expression of the nc-urf a gene completely restores the wild-type (non-mutator) phenotype. The significant similarity of the urf a gene to the mitochondrial var1 gene of S. cerevisiae and homologous genes in other yeasts suggests that the urf a gene product might be a ribosomal protein with a dual function in protein synthesis and maintenance of mitochondrial DNA integrity.
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