GLORIA

GEOMAR Library Ocean Research Information Access

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
    Description / Table of Contents: The first book of its kind, devoted exclusively to the assessment of DNA damage by the Comet assay in modern toxicology, The vast number of chemicals existing or being added into the environment, have globally aroused great concern regarding their adverse effects in human population. Development and validation of sensitive and better test systems which can assess the adverse effects of chemicals at an early stage for intervention strategies to be implemented in time is currently in progress. This book documents the latest research and showcases the versatile, state-of-the-art technique - the Comet assay - in the field of modern toxicology. The assay is a simple, sensitive rapid and visual technique for the quantitative and qualitative assessment of DNA damage in single cells. The Comet Assay in Toxicology is the first book of its kind to be devoted exclusively to the Comet assay and its applications as an important tool in modern toxicology. This multi-author book will serve as both a reference and a guide to investigations in the biomedical, biochemical and pharmaceutical sciences. Written by investigators from the fields of genetic toxicology and human epidemiology, the authors have first-hand knowledge from their chosen sub-specialities and are active contributors to the peer-reviewed scientific literature. The book is divided into five major sections, reflecting the range of interest in the exploitation of this assay. The book's scope begins with an introduction section reviewing its genesis for those new to the technique and the current knowledge of the various fields in which it finds wide acceptance. This section sets the scene by explaining why the assay has become the most sensitive and sought after assay in modern toxicology. Next is a whole section that considers various procedures being followed to assess different types of DNA damage in various cell types and is contributed by experts in the respective fields. The third section puts together the specific applications of the assay in the diverse fields ranging from genetic toxicity testing to human monitoring, and environmental toxicology. The fourth section consists of the guidelines and recommendations for the conduct of the assay in in vitro and in vivo systems, based on the recommendations of the International Workgroups on genotoxicity test procedures. Finally, the book draws to a close with an assessment of the statistics used for the understanding of the data generated by the assay. This is a unique reference book as it provides the scientific community with the advances in Comet assay as well as its applications. It also incorporates a detailed section with instant and comprehensive information on the procedure of the assay and the latest protocols being used worldwide as well as statistical analyses to be followed. The book is aimed at students as well as scientists in the area of molecular epidemiology and genetic toxicology
    Type of Medium: Online Resource
    Pages: 374 p , Online-Ressource , 43 b&w, ill
    Edition: RSC eBook Collection 1968-2009
    Series Statement: Issues in toxicology v. 5
    Language: English
    Note: Ebook , Preface-- Part I: Genesis of Comet assay-- Part II: Various procedures for the Comet assay-- Oxidative damage-- Water disinfection by-products-- Comet assay in Plants-- Double Strand-- Breaks in bacteria-- Comet - FISH-- Double strand breaks (DSBs) - radiation/challenge assay - Radiation-- Apoptosis-- Multiple mouse organs-- Part III: Applications of Comet assay-- Dietary intervention studies-- Comet assay in Mussels-- Exercise-- Arsenic-- DSBs - radiation/challenge assay - Radiation-- In vivo Comet assay-- In vitro parallelogram approaches-- Photobiology-- Comet assay in sperm-- Comet assay in Human monitoring-- Part IV: Guidelines for comet assay-- In Vitro And In Vivo Guidelines for the Comet Assay-- In vivo Guidelines for Comet-- Part V: Image analysis and Statistics-- Models for image analysis-- Statistics in comet assay.
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 2
    Online Resource
    Online Resource
    [Hamburg] : Marine Training Center Hamburg
    Keywords: Forschungsbericht ; Hafenschlepper ; Fernsteuerung ; Manöver ; Voith-Schneider-Propeller ; Simulation
    Type of Medium: Online Resource
    Pages: 1 Online-Ressource (96 Seiten, 7,11 MB) , Illustrationen, Diagramme
    Language: German
    Note: Förderkennzeichen BMWi 03SX443C , Verbundnummer 01180304 , Autoren dem Berichtsblatt entnommen , Unterschiede zwischen dem gedruckten Dokument und der elektronischen Ressource können nicht ausgeschlossen werden , Sprache der Zusammenfassungen: Deutsch, Englisch
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 3
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 4
    Publication Date: 2023-06-16
    Description: Comprehensive management of karst water resources requires sufficient understanding of their dynamics and karst-specific modeling tools. However, the limited availability of observations of karstic groundwater dynamics has been prohibiting the assessment of karst water resources at regional to global scales. This paper presents the first global effort to integrate experimental approaches and large-scale modeling. Using a global soil-moisture monitoring program and a global database of karst spring discharges, the simulations of a preliminary global karstic-groundwater-recharge model are evaluated. It is shown that soil moisture is a crucial variable that better distinguishes recharge dynamics in different climates and for different land cover types. The newly developed dataset of karst spring discharges provides first insights into the wide variability of discharge volumes and recharge areas of different karst springs around the globe. Comparing the model simulations with the newly collected soil-moisture and spring-discharge observations, indicates that (1) improvements of the recharge model are still necessary to obtain a better representation of different land cover types and snow processes, and (2) there is a need to incorporate groundwater dynamics. Applying and strictly evaluating these improvements in the model will finally provide a tool to identify hot spots of current or future water scarcity in the karst regions around the globe, thus supporting national and international water governance.
    Description: Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659
    Keywords: ddc:551.49 ; Karst ; Soil moisture ; Spring discharge analysis ; Groundwater recharge ; Global simulation model
    Language: English
    Type: doc-type:article
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 5
    Publication Date: 2024-05-23
    Description: 〈title xmlns:mml="http://www.w3.org/1998/Math/MathML"〉Abstract〈/title〉〈p xmlns:mml="http://www.w3.org/1998/Math/MathML" xml:lang="en"〉Hydrochemical data of karst springs provide valuable insights into the internal hydrodynamical functioning of karst systems and support model structure identification. However, the collection of high‐frequency time series of major solute species is limited by analysis costs. In this study, we develop a method to retrieve the individual solute concentration time series and their uncertainty at high temporal resolution for karst springs by using continuous observations of electrical conductivity (EC) and low‐frequency ionic measurements. Due to the large ion content and non‐negligible concentrations of aqueous complexes in karst systems, the concentration of each solute species occurring as free ion and as part of aqueous complexes are computed separately. The concentration of species occurring as free ions are computed considering their contributions to the total EC, whereas the concentration of the species as part of complexes are obtained from speciation calculations. The pivotal role of the complexation processes for the reconstruction of solute concentration time series starting from the EC signal is investigated in two karstic catchments with different geologies and temporal resolution of the available hydrochemical datasets, that is the Kerschbaum dolostone system in Austria and the Baget limestone system in France. The results show that complexation processes are significant and should be considered for the estimation of the total solute concentration in case of SO〈sub〉4〈/sub〉, Ca, Mg and HCO〈sub〉3〈/sub〉. The EC signal of a karst spring can be used to interpolate and quantify the dynamics of those solutes characterized by large contribution (approximately >6%) to the total EC and low relative variability, that is HCO〈sub〉3〈/sub〉, Ca and Mg. Moreover, the presented method can be used to estimate concentrations of solutes when applied to karst systems with stationary and hydrogeochemical homogeneous contributing area. On the contrary, the method is affected by large uncertainty in case of dynamic systems characterized by varying contributions of water from different geological areas. This study aims to contribute to the problem of hydrogeochemical data availability and to support future works on karst systems conceptualization.〈/p〉
    Description: Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659
    Description: École Polytechnique Fédérale de Lausanne http://dx.doi.org/10.13039/501100001703
    Description: European Regional Development Fund http://dx.doi.org/10.13039/501100008530
    Description: http://www.hydroshare.org/resource/fb92daaffced415fb7a991747e73adfa
    Keywords: ddc:551.9 ; electrical conductivity decomposition ; high‐resolution hydrochemical data ; hydrochemical modelling ; karst
    Language: English
    Type: doc-type:article
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 6
    ISSN: 1471-4159
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: There is evidence that an inflammatory microglial reaction participates in the pathophysiology of dopaminergic neuronal death in Parkinson's disease and in animal models of the disease. However, this phenomenon remains incompletely characterized. Using an in vitro model of neuronal/glial mesencephalic cultures, we show that the dopaminergic neurotoxin 1-methyl-4-phenylpyridinium (MPP+) stimulates the proliferation of microglial cells at concentrations that selectively reduce the survival of DA neurones. The mitogenic action of MPP+ was not the mere consequence of neuronal cell demise as the toxin produced the same effect in a model system of neuronal/glial cortical cultures, where target DA neurones are absent. Consistent with this observation, the proliferative effect of MPP+ was also detectable in neurone-free microglial/astroglial cultures. It disappeared, however, when MPP+ was added to pure microglial cell cultures suggesting that astrocytes played a key role in the mitogenic mechanism. Accordingly, the proliferation of microglial cells in response to MPP+ treatment was mimicked by granulocyte macrophage colony-stimulating factor (GM-CSF), a proinflammatory cytokine produced by astrocytes and was blocked by a neutralizing antibody to GM-CSF. Thus, we conclude that the microglial reaction observed following MPP+ exposure depends on astrocytic factors, e.g. GM-CSF, a finding that may have therapeutic implications.
    Type of Medium: Electronic Resource
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 7
    ISSN: 1471-4159
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: To better understand the neurotrophic function of the neurotransmitter noradrenaline, we have developed a model of mesencephalic cultures in which we find low concentrations (0.3–10 µm) of noradrenaline to be remarkably effective in promoting long-term survival and function of dopaminergic neurons. This protective action reproduced the effect of caspase inhibition. It was atypical in that it occurred independently of adrenoceptor activation and was mimicked by some antioxidants, redox metal chelators and the hydroxyl radical detoxifying enzyme catalase. Interestingly, intracellular reactive oxygen species (ROS) were drastically reduced by treatment with noradrenaline, indicating that the neurotransmitter itself acted as an antioxidant. Prevention of oxidative stress was, however, independent of the glutathione antioxidant defense system. Chemical analogues of noradrenaline bearing two free hydroxyl groups in the ortho position of the aromatic ring (o-catechols), as well as o-catechol itself, mimicked the survival promoting effects of the neurotransmitter, suggesting that this diphenolic structure was critical for both neuroprotection and reduction of ROS production. Paradoxically, the autoxidation of noradrenaline and the ensuing production of quinone metabolites may be required for both effects, as the neurotransmitter was spontaneously and rapidly degraded over time in the culture medium. These results support the concept that central noradrenergic mechanisms have a neuroprotective role, perhaps in part by reducing oxidative stress.
    Type of Medium: Electronic Resource
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 8
    ISSN: 1540-8159
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: ATTUEL, P., et al. : Relationship Between Selected Overdrive Parameters and the Therapeutic Outcome and Tolerance of Atrial Overdrive Pacing. There is a paucity of information on the influence of selected overdrive parameters on the clinical efficacy and tolerance of atrial overdrive algorithms to suppress atrial tachyarrhythmias. Data from a completed clinical trial investigating a new DDD+ overdrive algorithm implemented in a permanent pacemaker were analyzed. One-hundred patients with standard pacing indications and atrial tachyarrhythmias were enrolled and followed for 6 months in DDD and 6 months in DDD+ mode in a randomized, crossover fashion. The overdrive step size was programmed at the discretion of the investigators between 4 and 12 beats/min, overdrive plateau length between 10 and 32 beats, and maximum overdrive rate between 100 and 160 beats/min. The effects of DDD+ versus DDD mode on burden and incidence of atrial tachyarrhythmias stored in the mode switch memory were examined as a function of the programmed overdrive parameters. An overdrive step size between 7 and 12 beats/min, and higher a maximum overdrive rate between 121 and 160 beats/min were slightly more effective than lower programmed values, though 〉500 randomized, crossover observations would have been necessary to verify statistical significance. Overdrive pacing related symptoms mandated early manual deactivation of overdrive pacing in 4.7% of 85 evaluated patients. Overdrive was disabled without testing tolerability of less aggressive overdrive values. There was no link between patient symptoms and programmed overdrive step size or overdrive plateau length values. (PACE 2003; 26[Pt. II]:257–263)
    Type of Medium: Electronic Resource
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 9
    ISSN: 1471-4159
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Bax is a proapoptotic member of the Bcl-2 family of proteins. It is believed to exert its action primarily by facilitating the release of cytochrome c from the mitochondrial intermembrane space into the cytosol, leading to caspase activation and cell death. Because alterations in mitochondrial respiratory function, caspase activation and cell death with morphologic features compatible with apoptosis have been observed post mortem in the brain of patients with Parkinson's disease, we tried to clarify the potential role of Bax in this process in an immunohistochemical study on normal and Parkinson's disease post-mortem brain and primary mesencephalic cell cultures treated with MPP+. We found that Bax is expressed ubiquitously by dopaminergic (DA) neurons in post-mortem brain of normal and Parkinson's disease subjects as well as in vitro. Using an antibody to Bax inserted into the outer mitochondrial membrane as an index of Bax activation, no significant differences were observed between control and Parkinson's disease subjects, regardless of the mesencephalic subregion analysed. However, in Parkinson's disease subjects, the percentage of Bax-positive melanized SNpc neurons containing Lewy bodies, suggestive of DA neuronal suffering, was significantly higher than the overall percentage of Bax-positive neurons among melanized neurons. Furthermore, all melanized SNpc neurons in Parkinson's disease subjects with activated caspase-3 were also immunoreactive for Bax, suggesting that Bax anchored in the outer mitochondrial membrane of melanized SNpc neurons showing signs of neuronal suffering or apoptosis is increased compared with DA neurons that are apparently unaltered. Surprisingly, MPP+ treatment of tyrosine hydroxylase (TH)-positive neurons in primary mesencephalic cultures did not cause redistribution of Bax, although cytochrome c was released from the mitochondria and nuclear condensation/fragmentation was induced. Taken together, these findings suggest that in the human pathology, Bax may be a cofactor in caspase activation, but our in vitro data fail to indicate a central role for Bax in apoptotic death of DA neurons in an experimental Parkinson's disease paradigm.
    Type of Medium: Electronic Resource
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 10
    ISSN: 1540-8183
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: We report about the 6-month follow-up of 28 consecutive patients treated with a new tantalum stent (Wiktor™ stent, Medtronic, Inc.). Indication for stenting was the prevention of restenosis in eight patients (restenosis group), and threatening or acute closure after PTCA in 20 patients (acute closure group). Twenty-eight of 30 stents were successfully positioned in 27 of 28 patients (96%), whereas implantation failed twice in one patient. Immediate stent occlusion developed in two patients in the acute closure group (7.4%). Subacute stent occlusion was observed in three patients (11%), one in the restenosis group, two in the acute closure group, between 3 and 5 days after implantation. Coronary bypass surgery had to be performed in four patients (15%): one patient after failed stent placement, two after acute, and one after subacute stent thrombosis. Major bleeding complications related to the anticoagulative drug regimen occurred in nine patients (33%). Three patients (11%) died for reasons most probably not related to stent implantation. A 6-month angiographic follow-up revealed restenosis in two of 19 patients (11%), one patient in each group. Sixteen of the 27 stented patients (59%) reached 6-month follow-up without death, acute or subacute stent thrombosis, or restenosis. It is concluded that the Wiktor stent can be placed with a high rate of success. It may also reduce the risk of restenosis. The stent also offers the possibility to circumvent emergency bypass surgery in case of PTCA related vessel occlusion. Acute and subacute stent occlusion still remains an unsolved topic.
    Type of Medium: Electronic Resource
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...