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  • 1980-1984  (6)
  • 1
    Electronic Resource
    Electronic Resource
    Histamine release and hypotensive reactions in dogs by solubilizing agents and fatty acids: Analysis of various components in cremophor El and development of a compound with reduced toxicity (1982)
    Springer
    Inflammation research 12 (1982), S. 64-80 
    Details
    ISSN: 1420-908X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Anaphylactoid reactions in man following administration of drugs solubilized with cremophor El® (polyethylenglycolglycerol riconoleate) are a considerable clinical problem. Since these reactions occur in dogs on first exposure and in pigs on second exposure, the ‘dog model’ was used in this communication to analyse components and chemical modifications of cremophor El and its components for their clinical effects, their hypotensive actions and their histamine-releasing capacity. Two series of experiments in 1978 and 1980 were performed in 144 adult mongrel dogs of both sexes. In these studies histamine release wasnot related to the effect of the solubilizing agents as tensides and was elicited by rather low doses (about 10–100 mg/kg i.v.). The effect of these substances on blood pressure and on blood histamine levels was connected with distinct chemical features: the most potent compounds were oxethylated and additionally esterified unsaturated or hydroxylated fatty acids. Several phases in hypotensive reactions were observed, including an immediate response, a delayed blood pressure response and a late response about 15–20 min after injection. Only the delayed response was associated with histamine release. The combination of cardiovascular effects and histamine release was fatal on some occasions indicating that histamine release can be dangerous. Compared to cremophor El, the tenside effect was equal, but the toxicity was reduced in oxethylated 12-hydroxystearic acid. It is recommended that this solubilizer should be used in further extended studies in animals and — if these are successful—in clinical trials.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01965109
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  • 2
    Electronic Resource
    Electronic Resource
    Assay and identification of histamine in human gastric aspirate by a fluorometric-fluoroenzymatic technique. Its application in patients with chronic duodenal ulcer (1982)
    Springer
    Inflammation research 12 (1982), S. 17-25 
    Details
    ISSN: 1420-908X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Histamine assays can be unreliable in individual subjects or samples even though the particular method is in general working very well. Therefore the specificity and accuracy of histamine determination in the gastric aspirate of individual duodenal ulcer patients was thoroughly examined and shown to be satisfactory. Pitfalls of the fluorometric assay were investigated. A native (non-histamine) fluorescence in gastric aspirate which occurs before the addition of OPT was not removed by the original Shore procedure. In the combined assay (Dowex 50+ butanol extraction) this fluorescence no longer interferes with the assay. For the identification of histamine in a single gastric aspirate of an individual duodenal ulcer patient, the reversed blank (3M HCl added to the reaction mixture before OPT instead after OPT), excitation and fluorescence spectra, the heating test with spectra recorded and the HMT test were found to be reliable. The formaldehyde test and the heating test without recording the spectra were useless since they gave false negative results. Since the HMT test was regarded as a reference method it was thoroughly investigated both by theoretical considerations (enzyme kinetics) and by a series of measurements in a single patient as well as in a group of nine subjects. Samples from the period of peak acid output in response to pentagastrin showed an average histamine concentration of about 8 ng/ml and a histamine output of 1.5 μg/30 min.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01965100
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  • 3
    Electronic Resource
    Electronic Resource
    Histamine and peptic ulcer: Influence of sample-taking on the precision and accuracy of fluorometric histamine assay in biopsies of human gastric mucosa (1980)
    Springer
    Inflammation research 10 (1980), S. 175-185 
    Details
    ISSN: 1420-908X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract From a methodological point of view the relevance of clinical-biochemical trials depends on the answers to mainly four complexes of questions: (1) the reliability of the assays in the clinical situation to be tested, (2) the precision and accuracy of sample-taking, (3) the qualification of the design and the protocols in the clinical part of the trial and (4) the usefulness of the time concepts in the trial concerning biorhythms, seasonal influences, psychological trauma of diagnostic procedures and treatment. In this study mainly the second complex of questions was studied intensely. The precision of the fluorometric histamine assay in biopsy specimens from human gastric mucosa depended on several conditions: Biochemical technique, sample preparation and removal of biopsies from gastric mucosa via endoscopy. The CV% of the whole procedure was about 8-times higher than that of the biochemical technique. In clinical-biochemical studies on the significance of histamine or any other hormone (such as gastrin) in any disease (such as duodenal ulcer) it seems therefore useless to describe the precision of an assay only by the variance of the biochemical technique. Calculation of the histamine content as mean of 3 samples reduced the CV% from 27.2 to 14.9% and should therefore be recommended. The accuracy of the fluorometric histamine assay in biopsy specimens has been tested by several methods recommended by the IFCC and was found to be satisfactory. Conflicing results in the literature concerning the histamine content of human gastric mucosa could be explained on a methodological basis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02024207
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  • 4
    Electronic Resource
    Electronic Resource
    H1+H2-receptor antagonists for premedication in anaesthesia and surgery: A critical view based on randomized clinical trials with haemaccel and various antiallergic drugs (1980)
    Springer
    Inflammation research 10 (1980), S. 114-124 
    Details
    ISSN: 1420-908X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Histamine release by drugs used in anaesthesia and surgery has been often demonstrated in human volunteers, but only occasionally in patients. Three questions arose from these studies. (1) Is the incidence of histamine release high in patients during routine anaesthesia and surgery? (2) Can the clinical effects of histamine release in man be prevented by H1+H2-receptor antagonists? (3) Are there any side-effects of such a premedication? These problems were investigated in patients and volunteers by randomized controlled clinical trials using only one of the histamine-liberating drugs in man, the plasma substitute Haemaccel. This drug was chosen because it causes a reproducible histamine release in man and because its mechanism of action in man is largely known. (1) Out of 600 orthopaedic patients 30 (5%) showed anaphylactoid reactions following Haemaccel infusion. 26 of these had a histamine release of more than 1 ng histamine/ml plasma. Using predictive values this gives an efficiency of the test by nearly 98%. (2) In volunteers the combination of an H1-plus H2-receptor antagonist (dimethpyrindene and cimetidine) completely prevented the clinical effects of histamine release by Haemaccel (9 allergoid and anaphylactoid reactions in the control group, none in the H1+H2-group). The incidence of histamine release, however, remained unchanged. (3) The premedication was found to release histamine itself. Cimetidine was effective when given alone but especially in combination with chlorpheniramine (4 events out of 7 applications). The clinical side-effects of these premedication were mild since apparently the free histamine was largely blocked at the receptor sites. It is concluded that premedication with a combination of H1- and H2-receptor antagonists is indicated due to the high incidence of histamine release during anaesthesia and surgery induced by various drugs and treatments. Such premedication is effective but associated with mild side-effects. For this reason more extended clinical trials with dimethypyrindene plus cimetidine in patients are necessary before this premedication can be generally recommended.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02024192
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  • 5
    Electronic Resource
    Electronic Resource
    Histamine content, diamine oxidase activity and histamine methyltransferase activity in human tissues: Fact or fictions? (1984)
    Springer
    Inflammation research 14 (1984), S. 325-334 
    Details
    ISSN: 1420-908X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract To understand the role of histamine in the aetiology and pathogenesis of human diseases reliable data are urgently needed for the histamine content and for the activities of histamine-forming and-inactivating enzymes in human tissues. In order to make a substantial progress toward this aim a tissue-sampling programme during surgical interventions was carefully conceived and conducted. From March 1982 until January 1983 106 tissue specimens were taken from 56 patients who underwent surgery. Only healthy tissues, not injured or oedematous, and without adherent structures were taken by only one surgeon who was interested in this research and experienced in tissue preparation procedures in biochemistry. The times of ‘warm’ ischaemia during the operative procedures were visually estimated, the times between resection of the organs or specimens and deep-freezing of the tissues were precisely recorded. Compared to previous work in the literature and especially to our own work using the same assays for determination higher histamine contents were found in this study in most of the tissues, in particular in the gastrointestinal tract. Also the diamine oxidase activities were considerably higher in many organs, e.g. 3–4 times higher in the gastrointestinal tract when compared with those in publications of our group who used always the same analytical test. However, the histamine methyltransferase activities in this study were not at variance to those determined in previous investigations. Many of them were reported in this communication for the first time. Since the methods for histamine determination and those for measuring enzymic activities were not different in this study and in previous communications of our group we are convinced that the optimized tissue-sampling and-preparation techniques were responsible for the higher values in this communication. But the problem of the ‘warm’ ischaemia period could not be solved by sample-taking procedures of this type during operations. There are good reasons to prefer biopsy specimens for the analysis of histamine storage and metabolism in human tissues in health and disease, but — unfortunately — they are not always available.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01973821
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  • 6
    Electronic Resource
    Electronic Resource
    The reactions of polyacetylene with trimethyloxonium hexachloroantimonate. Covalent doping of (CH)xPresented in part at the Symposium on Conducting Polymers, Division of Polymer Chemistry (Abstract No. 105), 183rd National Meeting of the American Chemical Society, Las Vegas, 1982. (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 1929-1940 
    Details
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polyacetylene, (CH)x, has been doped with trimethyloxonium hexachloroantimonate, (CH3)3O+SbCl6-(1), in dichloromethane and acetonitrile. The maximally doped (CH)x films have moderate conductivities [σRT(CH2Cl2) = 10, σRT(CH3CN) = 0.7 Ω-1 cm-1]. Reactions between 1 and (CH)x CH2Cl2 or CH3CN were followed in situ by 1H nuclear magnetic resonance spectroscopy and x-band electron spin resonance spectroscopy. It was found that the reactions in the two solvents are different. In dichloromethane the dopant is SbCl5, which forms from the decomposition of 1, and doping proceeds by electron removal from (CH)x chains. Based on the ESR signal loss, an estimate can be made of the diffusion rate of SbCl5, into the (CH)x fibrils in CH2Cl2; it is found to be ca. 10-17 cm2/s. In acetonitrile the dopant appears to be either CH3CNCH3+, H+, CH3+, or a combination of one or more of these dopants. It is postulated that the CH3CNCH3+, CH+3, and/or H+ dopant covalently binds to the (CH)x chain. X-ray photoelectron spectra show that films doped with excess 1 in both solvents have approximately one SbCl6- per 33 CH units.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.170210705
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