Library

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
    Springer
    Acta neurochirurgica 105 (1990), S. 158-168 
    ISSN: 0942-0940
    Keywords: Brain edema ; cerebral blood flow ; brain tissue hydraulic resistance ; somatosensory evoked potential ; intracranial pressure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary To evaluate the potency of putative secondary mediators of brain edema and their possible contribution to edema related brain dysfunction an infusion model of brain edema was developed in rats. 100 ul of fluid (saline, 20% nonautologous protein) was infused over one hour into the left forebrain white matter through a stereotaxically placed (+ 1.2 mm ant to bregma, 3 mm lateral and 2.9 mm depth) 25 G needle. Brain tissue hydraulic resistance (Rt), regional cerebral blood flow (rCBF), cortical somatosensory evoked potentials (SEPs) and intracranial pressure (ICP) (intraventricular needle) were monitored during the infusion and rCBF CO2 reactivity (hydrogen clearance), local brain water content (microgravimetry), BBB integrity (Evans Blue 2%) and brain histology (H & E, Solochrome-cyanin) were evaluated after the infusion. Saline infusates caused no physiological dysfunction despite ipsilateral expansion and vacuolation of the subcortical white matter, separation of axonal bundles and a significant decrease (p=3.8×10−5)in local subcortical tissue specific gravity. Cortical histology and specific gravity adjacent to the infusion locus were normal. Rt significantly decreased (p=6.5×10−4) during the infusion but there were only minor increases in ICP. Findings with 20% protein infusates were similar despite a focal 65% decrement in the rCBF CO2 reactivity adjacent to the infusion site. This study has shown that a simple and inexpensive model of infusion brain edema can be created in the rat and that it provides a useful model for assessing the physiological effects of mediator compounds in the infusate. Potential applications and methodological improvements for this model are discussed.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 0942-0940
    Keywords: Brain edema ; blood brain barrier ; serum protein ; evoked potential ; glioma ; cerebral blood flow ; permeability factor
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The feline infusion model of brain edema was used to evaluate the pathophysiological effects of 0.6ml infusions of autologous serum protein (66%), human serum protein (66%), human glioma cyst fluid and a tissue culture medium (TCM) on the structure and function of the forebrain white matter. These infusions increased local white matter water content by between 10.8 and 12.5 ml/100 g brain and were associated with moderate increases in ICP and CSF outflow resistance and a significant decrease in lumped craniospinal compliance. Cortical somatosensory potentials, motor evoked potentials, EEG and local cerebral blood flow (rCBF) at normocapnia were generally unchanged by the various infusions. All infusates except the 66% autologous serum protein infusion impaired rCBF CO2 reactivity. Histologically all infusates caused marked extracellular edema. The autologous serum protein infusion caused no additional histological changes whereas the glioma cyst infusates caused profound endothelial and astrocytic swelling, focal endothelial necrosis, basement membrane disruption, perivascular microglial reaction and pavementation and perivascular migration of polymor-phonuclear leukocytes. Similar but less marked changes were seen after infusion of human serum protein whilst the TCM produced only minimal changes. The intensity and extent of Evans Blue extravasation into the forebrain white matter was greatest with glioma cyst infusates and with all infusions reflected the extent to microvascular changes. These studies show that products derived from gliomas cause additional damage to the blood-brain-barrier than that caused by non-autologous serum proteins. These results add further support for the existence of glioma derived permeability factors (GDPF), but suggest neither serum proteins nor glioma derived compounds in the white matter interstitium significantly influence local electrophysiological function. Some limitations of the infusion edema model when using non-autologous infusions and difficulties quantitating brain dysfunction are emphasised.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Acta neurochirurgica 115 (1992), S. 53-59 
    ISSN: 0942-0940
    Keywords: Bradykinin ; intracranial pressure ; evoked potentials ; cerebral blood flow ; brain edema ; blood brain barrier
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The feline infusion model of brain edema was used to evaluate the role of bradykinin in the etiology and pathophysiology of vasogenic brain edema. Bradykinin (3 or 90 ug in 600 μL saline) did not alter normocapnic regional cerebral blood flow (rCBF) nor induce specific changes in either the somatosensory (SEP) or motor (MEP) evoked potentials. The mean increases in ICP (from 4.5 to 16.1 mmHg) and peri-infusion white matter water content (from 69.4 to 79.8 ml/100 g tissue), mean decrease in lumped craniospinal compliance (from 0.040 to 0.014 ml/mmHg) and local histological changes were all similar to those after 600 μL saline infusion. The interstitial bradykinin infusion caused focal blood-brain-barrier (BBB) opening to Evans Blue dye and was chemotaxic for granulocytes. After the infusion there was a global loss of rCBF CO2 reactivity but there was no ischemia at normocapnia. These results show that bradykinin in brain edema fluid, at concentrations greater than those found in neuropathological conditions, can open the BBB of normal cerebral parenchymal capillaries and cause vascular dysregulation. In neuropathological conditions bradykinin may therefore potentiate formation of vasogenic brain edema but does not contribute to perilesional brain dysfunction.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    ISSN: 0942-0940
    Keywords: Blood brain barrier ; cerebral blood flow ; intracranial pressure ; arachidonic acid ; brain oedema ; evoked potential
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Arachidonic acid solution (2 to 15 mg/ml) was infused into the right forebrain white matter of anaesthetised cats over three hours to evaluate its contribution to the genesis and pathophysiology of vasogenic brain oedema. The 0.6 ml infusion increased local white matter water content by a mean of 11.3 ml/100 g tissue but did not increase cortical water content. Histological studies revealed local expansion and trabeculation of the white matter with aggregations of granulocytic neutrophils in the venules and perivenular brain. The adjacent cortical cytoarchitecture was normal. The white matter around the infusion site was stained lightly and over a variable area (15–20 mm2) by intravenously administered Evans Blue dye 2%. Regional cerebral blood flow (rCBF) adjacent to the frontal infusion did not change significantly during the period of infusion and remained similar to rCBF in the contralateral hemisphere. Following the arachidonic acid infusion regional CBF CO2 reactivity was normal and three was no asymmetry of either cortical somatosensory evoked potential (SEP) or motor evoked potential (MEP) waveforms. The increase in brain water content and changes in the ICP and ICP related biodynamics (pressure-volume index, lumped craniospinal compliance and CSF outflow resistance) were similar to those seen following infusion of 0.6 ml saline. These studies suggest that free intraparenchymal arachidonic acid, at concentrations exceeding those occurring in most neuropathological conditions, can increase the normal brain parenchymal capillary permeability but does not disrupt focal cerebrovascular and electrophysiological function. The clinical implications of these findings are discussed.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Journal of insect behavior 4 (1991), S. 773-792 
    ISSN: 1572-8889
    Keywords: Delia antiqua ; Anthomyiidae ; Diptera ; herbivore ; egg-laying ; host-finding ; sensory systems ; chemoreception ; n-dipropyl disulfide
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Behavioral responses of female onion flies, Delia antiqua (Meigen), to hostplant cues were quantified during encounters of individual flies with onion plants and onion foliar surrogates. The behavioral repertoire of such females included sitting, grooming, running up and down foliar surfaces, extension of the proboscis such that the labellum contacted foliar and soil surfaces, movements of the tip of the abdomen over surfaces (surface probing), subsurface probing of soil crevices with the ovipositor, and oviposition. Sequences of behaviors preceding oviposition were probabilistic rather than highly stereotyped but generally followed the order given above. Foliar surrogates were used to determine the effects of n-dipropyl disulfide (Pr2S2) on the sequence of behaviors leading up to oviposition. The addition of a Pr2S2-treated surrogate to a cage increased the frequency of alighting on that surrogate but also increased alighting on a nearby foliar surrogate without Pr2S2. After alighting, females encountering surrogates treated with Pr2S2 had shorter latencies to proboscis extension and surface probing, spent less time sitting and grooming, and had runs of shorter duration. These females were also more likely to make the transition from probing of surfaces of foliage and soil to subsurface probing of soil crevices and oviposition. Thus, rather than mediating a particular step in the behavioral sequence, Pr2S2 played a role throughout the sequence leading up to oviposition. Collectively, these data and past studies on the onion fly support the hypothesis that egglaying is triggered by a temporal summation of inputs to the central nervous system from various sensory modalities rather than strict behavioral chaining, with each transition effected by some unique cue.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    Springer
    Journal of chemical ecology 13 (1987), S. 1261-1277 
    ISSN: 1573-1561
    Keywords: Onion fly ; onion maggot ; Delia antiqua ; Hylemya antiqua ; Diptera ; Anthomyiidae ; host selection ; oviposition ; dipropyl disulfide ; behavior ; herbivore ; plant-insect interactions
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Onion fly females,Delia antiqua (Diptera: Anthomyiidae) laid the most eggs on ovipositional dishes havingn-dipropyl disulfide (Pr2S2) release rates of 1–6 ng/sec from polyethylene capsules placed beneath a sand substrate. When dipropyl disulfide was released from the wax coating of surrogate foliage rather than from the substrate, ovipositing females again responded differentially to various concentrations, laying more eggs around stems containing 0.075 and 0.089 mg/stem. Factorial combinations of several concentrations released from surrogate foliage and substrate showed that releases from surrogate foliage stimulated four times more egg-laying than releases from the substrate. Females tended to lay more eggs around surrogate stems having Pr2S2 at the base rather than on the upper half of foliage. Observations of individual females performing preovipositional examining behaviors on Pr2S2-treated surrogate stems indicated that females tended to land on the upper portions of the foliage, but after landing, spent most of their time examining areas of soil and surrogate within 1 cm of the soil-surrogate foliage interface. Surrogate stems provide a realistic context for investigating effects of plant chemicals on host-acceptance behaviors.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Journal of chemical ecology 15 (1989), S. 905-916 
    ISSN: 1573-1561
    Keywords: Onion fly ; Delia antiqua ; Diptera ; Anthomyiidae ; Erwinia carotovora varcarotovora ; Klebsiella pneumoniae ; food attractant ; ovipositional stimulant ; dipropyl disulfide ; 2-phenylethanol ; pentanoic acid
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Decomposing onions at certain microbial successional stages produce potent volatile attractants and ovipositional stimulants of the onion fly,Delia antiqua (Diptera: Anthomyiidae). A reproducible source of these compounds was obtained by culturingErwinia carotovora var.carotovora (EC) on sterile onion tissue. In laboratory choice tests, EC-inoculated onion was more attractive thanKlebsiella pneumoniae (KP) cultured on onion, EC cultured on potato (a nonhost of onion fly), or the chemical synthetic baits dipropyl disulfide and an aqueous solution of 2-phenylethanol and pentanoic acid. Onion flies were mildly attracted to potato after inoculation with EC, but females did not accept EC-inoculated potato for oviposition. This work emphasizes that sources of semiochemicals may need to be defined microbiologically as well as physically and chemically.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 8
    Electronic Resource
    Electronic Resource
    Springer
    Journal of chemical ecology 10 (1984), S. 1477-1488 
    ISSN: 1573-1561
    Keywords: Delia antiqua ; onion fly ; Diptera ; Anthomyiidae ; food attractants ; host attractants ; microbial attractants ; Klebsiella pneumoniae ; bacteria ; Allium ; onion ; garlic ; chive
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Of various chopped vegetables tested,Allium spp. high in propyl-containing alkyl sulfides (e.g.,cepa group) caught the most onion flies in trapping tests in the field. Fly catches to chopped onion increased with bait quantity. Attractancy of chopped onion changed dramatically during aging in the field; catch increased over the first few days, peaked at ca. fivefold over fresh material by 3–5 days, and then declined sharply. This age-dependent increase in attraction was not seen for garlic (known to have antimicrobial properties) nor with chopped onion mixed with chopped garlic. These data suggested that attraction of onion flies to onions was strongly influenced by microbial activity associated with decomposing onions. The bacteriumKlebsiella pneumoniae was identified as a major colonizer of onions maximally attractive to onion flies. This increased attraction is not due to the previously reported microbially produced volatiles ethyl acetate and tetramethyl pyrazine.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 9
    Electronic Resource
    Electronic Resource
    Springer
    Journal of chemical ecology 15 (1989), S. 719-730 
    ISSN: 1573-1561
    Keywords: Onion fly ; Delia antiqua ; Diptera ; Anthomyiidae ; oviposition ; deterrent ; capsaicin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract In laboratory choice experiments, the spices dill, paprika, black pepper, chili powder, ginger, and red pepper deterredDelia antiqua oviposition by 88–100%. Dose-response choice tests demonstrated that 1 mg of ground cayenne pepper (GCP) placed within 1 cm of artificial onion foliage reduced oviposition by 78%. A synthetic analog of capsaicin, the principal flavor ingredient of red peppers, deterred oviposition by 95% when present at 320 ppm in the top centimeter of sand (the ovipositional substrate). However, in no-choice conditions 10 mg GCP was not an effective deterrent. Sevana Bird Repellent and Agrigard Insect Repellent both use red pepper as a principal ingredient; at recommended field rates, neither of these materials was an effective ovipositional deterrent either in laboratory or field. Capsaicin-based materials do not appear to be candidates for onion maggot control via behavioral modification.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 10
    Electronic Resource
    Electronic Resource
    Springer
    Journal of chemical ecology 11 (1985), S. 435-440 
    ISSN: 1573-1561
    Keywords: Delia (Hylemya) antiqua ; Diptera ; Anthomyiidae ; onion fly ; onion maggot ; tube trap ; insect attractants
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Responses of onion flies,Delia antiqua, to known attractants were measured in the laboratory with a novel tube-trap bioassay. The relative numbers of flies caught in tube traps baited with enzymatic yeast hydrolysate, brewer's yeast, andn-dipropyl disulfide were similar to those obtained previously with cone traps in the field. Changing the shape of the bioassay cage from a cuboid to a cylinder decreased the experimental error obtained from analysis of variance, as did rotating the floor of the circular cage. This bioassay should be useful in evaluating attractants for other insects that orient along the substrate.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...