ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
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
    Electronic Resource
    Electronic Resource
    Methylglyoxal production in bacteria: suicide or survival? (1998)
    Springer
    Archives of microbiology 170 (1998), S. 209-218 
    Details
    ISSN: 1432-072X
    Keywords: Key words Methylglyoxal ; Cytoplasmic pH ; Potassium ; Glyoxalase ; Glycolysis ; Metabolism
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Methylglyoxal is a toxic electrophile. In Escherichia coli cells, the principal route of methylglyoxal production is from dihydroxyacetone phosphate by the action of methylglyoxal synthase. The toxicity of methylglyoxal is believed to be due to its ability to interact with the nucleophilic centres of macromolecules such as DNA. Bacteria possess an array of detoxification pathways for methylglyoxal. In E. coli, glutathione-based detoxification is central to survival of exposure to methylglyoxal. The glutathione-dependent glyoxalase I-II pathway is the primary route of methylglyoxal detoxification, and the glutathione conjugates formed can activate the KefB and KefC potassium channels. The activation of these channels leads to a lowering of the intracellular pH of the bacterial cell, which protects against the toxic effects of electrophiles. In addition to the KefB and KefC systems, E. coli cells are equipped with a number of independent protective mechanisms whose purpose appears to be directed at ensuring the integrity of the DNA. A model of how these protective mechanisms function will be presented. The production of methylglyoxal by cells is a paradox that can be resolved by assigning an important role in adaptation to conditions of nutrient imbalance. Analysis of a methylglyoxal synthase-deficient mutant provides evidence that methylglyoxal production is required to allow growth under certain environmental conditions. The production of methylglyoxal may represent a high-risk strategy that facilitates adaptation, but which on failure leads to cell death. New strategies for antibacterial therapy may be based on undermining the detoxification and defence mechanisms coupled with deregulation of methylglyoxal synthesis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002030050635
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Egg laying inAplysia (1989)
    Springer
    Journal of comparative physiology 164 (1989), S. 835-847 
    Details
    ISSN: 1432-1351
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Aplysia egg laying is a complex sequence of head and neck movements initiated by the release of ovulatory and neuroactive hormones from the neurosecretory bag cells. This behavioral pattern is difficult to study in reduced preparations, because they do not show ovulation or egg laying behaviors. This paper describes the use of chronically implanted electrodes to elicit normal neurosecretory activity and provides an analysis of egg laying behaviors and the underlying muscle activity in intact, freely behavingA. californica andA. brasiliana. 1. Bag cell discharges elicited with a fine wire electrode implanted in the connective tissue sheath above the cell bodies were typically without noxious behavioral side effects. 2. Following selectively elicited bag cell discharges, egg laying consisted of four rhythmic head and neck movements that were separated functionally into appetitive behaviors (‘waves’ and ‘undulations’) used to explore and prepare the substrate and consummatory behaviors (‘weaves’ and ‘tamps’) used to distribute and attach the egg string. The amount of time an animal performed consummatory behaviors was positively related to the amount of eggs deposited. By contrast, the appetitive phase of egg laying was independent of the size of the egg mass. 3. The individual behaviors and their temporal sequence were similar following selectively elicited bag cell discharges, spontaneous discharges of animals with implanted electrodes and during normal egg laying of unoperated animals. 4. Three longitudinal muscle systems occurred within the head and neck. Following a selectively elicited bag cell discharge, spatially and temporally coordinated patterns of EJP bursts of different durations were recorded chronically from each muscle group. These EJP patterns were characteristic for specific head and neck movements used in appetitive and consummatory egg laying behaviors.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00616755
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Neuronal input contributes to sequence of Aplysia egg laying behaviors (1996)
    Springer
    Journal of comparative physiology 179 (1996), S. 775-783 
    Details
    ISSN: 1432-1351
    Keywords: Bag cells ; Reproduction ; Aplysia
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Egg laying in Aplysia is controlled by the bag cell neuroendocrine system, which releases multiple peptides during a long-lasting electrical discharge. Following the discharge, a fixed sequence of head and neck movements is performed in which two phases can be distinguished: an appetitive or preparatory phase, in which the substrate is prepared, and a consummatory phase, when the egg string is deposited. During egg laying, feeding responses are suppressed. In this study, Aplysia fasciata was used. When the movement of the egg string through the genital groove was prevented by ligation, lesions of the nerve innervating the genital pore completely abolished the consummatory egg-laying behaviors. This shows that a nervous connection between the genital pore area and the central nervous system is important for the consummatory egg-laying behaviors. We found that suppression of feeding responses to seaweed occurred only during the consummatory phase of egg laying in controls, but animals with ligated genital grooves continued to show normal responses to food. It is hypothesized that a neuronal feedback, possibly together with the bag cell peptides, is critical for the temporal organization of egg-laying behavior in Aplysia.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00207356
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Egg laying inAplysia (1989)
    Springer
    Journal of comparative physiology 164 (1989), S. 849-857 
    Details
    ISSN: 1432-1351
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary 1. Central pathways for bag cell activation were identified by examining the frequency of spontaneous egg laying episodes in animals with central connective lesions. Bilateral lesions of the cerebropleural (but not the cerebropedal) connectives abolished spontaneous egg laying. In contrast, bilateral lesions of all cerebral ganglion peripheral nerves did not abolish spontaneous egg laying, suggesting that sensory input to the cerebral ganglion is not necessary for activating the bag cells. 2. Backfilling either pleuroabdominal connective labelled cell bodies in the cerebral ganglia (via the ipsilateral cerebropleural connective) that could project to the bag cells. Focal extracellular stimulation of these stained clusters activated the bag cells in isolated brains. 3. Central pathways for initiating egg laying behaviors were identified by selectively eliciting bag cell discharges in animals with central connective lesions. Bilateral lesions of the cerebropedal (but not the cerebropleural) connectives completely abolished elicited egg laying behaviors. 4. Pathways for motor output during rhythmic head and neck movements were identified by eliciting bag cell discharges in animals with peripheral nerve lesions. Bilateral lesions of the four tegumentary nerves in combination with the anterior pedal nerve completely abolished elicited egg laying behaviors, indicating that these nerves are necessary for normal motor output. A normal pattern of egg laying behaviors occurred when the four tegumentary and the anterior pedal nerves were left intact and all other pedal ganglion nerves were lesioned bilaterally, indicating that these nerves are also sufficient for normal motor output. 5. We conclude that i) the cerebropleural connectives are necessary for initiation of spontaneous bag cell discharges but not egg laying behaviors, ii) the cerebropedal connectives are necessary for initiation of egg laying behaviors but not bag cell discharges, and iii) the motor output for egg laying behaviors is distributed through a limited number of pedal ganglion nerves.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00616756
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    The structure ofcis-dichloro-bis-(triphenylphosphine)platinum(II); a product in the reaction ofcis-[PtCl2(CO)(PPh3)] with tin (II) chloride (1982)
    Springer
    Journal of chemical crystallography 12 (1982), S. 449-458 
    Details
    ISSN: 1572-8854
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Abstract The reaction ofcis-[PtCl2(CO)(PPh3)] with two equivalents of SnCl2. 2H2O in acetone solution allows isolation ofcis-[PtCl2(PPh3)2] as the acetone solvate, the crystal structure of which has been determined. Crystals ofcis-[PtCl2(PPh3)2]·C3H6O are monoclinic, space groupP21/c (No. 14) with four formula units in a cell of dimensionsa=10.288(3),b=24.372(5),c= 15.367(3) Å, /gb=98.07(2)°. The structure was solved by the heavy-atom method and refined by full-matrix least-squares calculations to a finalRof 0.033 for 3761 reflections withI〉(I). The crystal structure contains discrete well-resolvedcis-PtCl2(PPh3)2 molecules with acetone of solvation filling cavities in the crystal structure. The Pt coordination is slightly distorted square-planar with Pt-Cl 2.333(2) and 2.356(2), Pt-P 2.251(2) and 2.265(2) Å, P-Pt-P 97.8(1), and Cl-Pt-Cl 87.1(1)°.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01161406
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    The crystal structure and absolute configuration of(S)-((S)-1-chloroethyl)-methyl-1-naphthalenylphenylsilane (1983)
    Springer
    Journal of chemical crystallography 13 (1983), S. 421-429 
    Details
    ISSN: 1572-8854
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Abstract Recrystallization from hexane of diastereomeric (S)-((R/S)-1-chloroethyl)-methyl-1-naphthalenylphenylsilane, C19H19ClSi, initially yields crystals composed of only one stereoisomer, whose crystal structure has been determined. The crystals are orthorhombic, space groupP212121 (No. 19), with four formula units in a cell of dimensionsa=7.729(4),b=11.239(1), andc=19.214(3) Å. Intensities were measured (Mo radiation) for all reflections having 2θ〈43°, but only part of the data were collected from 43 to 60° due to crystal decomposition. The structure was solved by direct methods and refined by full-matrix least-squares calculations to a finalR of 0.0378 for 2074 reflections havingI〉3σ(I). The crystal structure is composed of discrete molecules having theS configuration at both Si and alpha-C(2) asymmetric centers, and in which the naphthalenyl group bonded to Si is juxtaposed to the Cl bonded to C(2). The plane of the naphthalenyl group almost eclipses the Si-C(methyl) bond, and a similar relationship exists between the phenyl group and the Si-C(2) bond.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01194756
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Farben, Lacke, Überzüge (1939)
    Springer
    Fresenius' Zeitschrift für analytische Chemie 116 (1939), S. 209-215 
    Details
    ISSN: 1618-2650
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01358939
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Die Verwendung von Trockeneis als Vorbeugungsmittel gegen atmosphärische Oxydation (1942)
    Springer
    Fresenius' Zeitschrift für analytische Chemie 124 (1942), S. 125-125 
    Details
    ISSN: 1618-2650
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01393151
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    facet.materialart.
    Unknown
    Methylglyoxal production in bacteria: suicide or survival? (1998)
    Springer
    Details
    Publication Date: 1998-09-09
    Print ISSN: 0302-8933
    Electronic ISSN: 1432-072X
    Topics: Biology
    Published by Springer
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 10
    facet.materialart.
    Unknown
    Die Verwendung von Trockeneis als Vorbeugungsmittel gegen atmosphärische Oxydation (1942)
    Springer
    Details
    Publication Date: 1942-03-01
    Print ISSN: 0016-1152
    Topics: Chemistry and Pharmacology
    Published by Springer
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...