301
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Gross-Fengels W, Friedmann G, Kuhn M, Huber R, Dommasck J, Neufang KF. [Techniques, results and risks of chemoembolization of malignant liver tumors]. AKTUELLE RADIOLOGIE 1991; 1:97-104. [PMID: 1878387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
This is a report on 55 chemoembolizations (ChE) in 31 patients with primary (n = 10) and secondary (n = 21) liver malignomas. Probing of the segmental arteries was always possible by means of a coaxially placed 3F catheter system. Chemoembolization was effected with a mixture of ivalon particles, 20 mg mitomycin or 40-60 mg epirubicin and an ethibloc solution. More than 75% of the patients showed a decrease in tumour size and/or tumour density. The proportion of surviving patients was 80.6% after 6 months. Within this period, extrahepatic metastases were seen for the first time in 19.4% of the patients. References in literature on techniques and results of chemoembolization are discussed.
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302
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Kuhn M, Otten A, Frölich JC, Förstermann U. Endothelial cyclic GMP and cyclic AMP do not regulate the release of endothelium-derived relaxing factor/nitric oxide from bovine aortic endothelial cells. J Pharmacol Exp Ther 1991; 256:677-82. [PMID: 1847208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The present study was designed to investigate whether cyclic GMP or cyclic AMP modulates the release of endothelium-derived relaxing factor/nitric oxide (EDRF/NO) in cultured bovine aortic endothelial cells (BAE cells). BAE cell-conditioned medium was transferred onto rat fetal lung fibroblasts (RFL-6 cells) and the increase in cyclic GMP in these cells was used as a sensitive bioassay of EDRF/NO activity. BAE cells released a material that markedly enhanced cyclic GMP in RFL-6 cells. The synthesis of this substance could be stimulated with bradykinin (10 nM) or Ca++ ionophore A23187 (1 microM) and was completely prevented by treatment of the BAE cells with the EDRF/NO synthesis inhibitors NG-nitro-L-arginine (100 microM) or NG-methyl-L-arginine (1 mM). Addition of hemoglobin (10 microM) or incubation of the RFL-6 detector cells with methylene blue (10 microM) also abolished the cyclic GMP increase in the RFL-6 cells. The release of EDRF/NO by bradykinin and A23187 was accompanied by an approximately 2-fold increase in the cyclic GMP content in the producing BAE cells (in the presence of the cyclic GMP phosphodiesterase inhibitor M&B 22,948, 0.1 mM). Incubation of BAE cells with atrial natriuretic peptide (0.1 microM) or sodium nitroprusside (10 microM) enhanced cyclic GMP content of BAE cells 6.5-fold and 4.1-fold, respectively (in the presence of M&B 22,948, 0.1 mM). These increases in the cyclic GMP levels in BAE cells had no effect on basal or bradykinin- and A23187-stimulated release of EDRF/NO. Bradykinin (10 nM) and A23187 (1 microM) also stimulated prostacyclin production in BAE cells 2.4-fold and 5.6-fold, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)
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303
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Parks RW, Zec RF, Kuhn M, Vicari S, Feldman E, Coburn KL, Ashford JW, Crockett DJ, Moreno MA, Rashid A. Electrocortical mapping, MRI, and neuropsychological measures: evidence of Alzheimer's disease in the presence of vascular lesions. Arch Clin Neuropsychol 1991; 6:393-408. [PMID: 14589529] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/27/2023] Open
Abstract
We report here a case study of a 76-year-old woman with a high school education, whose presenting psychiatric symptomatology indicated dementia of unknown etiology. Neuropsychological test results were consistent with AD, but diagnosis was complicated by an MRI showing a large right hemisphere cortical infarct and scattered subcortical changes leading to a diagnosis of possible AD. Electrocortical mapping showed the right hemisphere infarct, and gave independent evidence suggestive of AD in the relatively intact left hemisphere. This case demonstrates the utility of multidimensional assessment as an aid to differential diagnosis.
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304
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Abstract
EDRF/NO released from bovine aortic endothelial cells was measured by transferring conditioned medium to rat fetal lung fibroblasts (RFL-6 cells). These cells contain considerable amounts of soluble guanylyl cyclase. The increase in cyclic GMP in these cells provided a sensitive bioassay for EDRF/NO activity. Bovine aortic endothelial cells released a material that markedly enhanced cyclic GMP in RFL-6 cells. The synthesis of this substance could be stimulated with bradykinin (10 nM) or Ca2+ ionophore A23187 (1 microM) and was completely prevented by treatment of the endothelial cells with the EDRF/NO synthesis inhibitor, NG-L-arginine (100 microM), or incubation of the RFL-6 detector cells with the inhibitor of soluble guanylyl cyclase, methylene blue (10 microM). The release of EDRF/NO by bradykinin and A23187 was accompanied by an about two-fold increase in the cyclic GMP content in the producing endothelial cells. Incubation of bovine aortic endothelial cells with atrial natriuretic peptide (0.1 microM) or sodium nitroprusside (10 microM) enhanced their cyclic GMP content 6.5-fold and 4.1-fold, respectively. These increases in endothelial cyclic GMP levels had no effect on basal or bradykinin- and A23187-stimulated release of EDRF/NO. We conclude that cyclic GMP does not feed back on EDRF/NO formation or release in bovine aortic endothelial cells.
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305
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Parks RW, Zec RF, Kuhn M, Vicari S, Feldman E, Coburn KL, Ashford J, Crockett DJ, Moreno MA, Rashid A. Electrocortical mapping, MRI, and neuropsychological measures: Evidence of Alzheimer's disease in the presence of vascular lesions. Arch Clin Neuropsychol 1991. [DOI: 10.1093/arclin/6.4.393] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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306
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Soltermann B, Frutiger A, Kuhn M. Lightning injury with lung bleeding in a tracheotomized patient. Chest 1991; 99:240-2. [PMID: 1984964 DOI: 10.1378/chest.99.1.240] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
A 68-year-old man, who had undergone laryngectomy six months earlier, was struck by lightning and developed pulmonary hemorrhage. This was attributed to pulmonary barotrauma due to a lightning blast via his tracheostoma.
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307
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Hesselmann J, Kuhn M, Ostendorf PC, Huep WW. [Acute alveolitis in ulcerative colitis: extra-intestinal organ complication or drug side effect]. LEBER, MAGEN, DARM 1991; 21:26-8, 31. [PMID: 2027303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The histories of three possible cases of 5-ASA-induced toxic interstitial lung disease are presented. In addition diagnostical methods and procedures for the differential-diagnosis are discussed and as diagnostical program for the identification of remedy-induced toxic lung-damages is explained.
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308
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Sham TK, Yiu YM, Kuhn M, Tan KH. Erratum: "Electronic structure of ordered and disordered Cu3Au: The behavior of the Au 5d bands". PHYSICAL REVIEW. B, CONDENSED MATTER 1990; 42:9194. [PMID: 9995145 DOI: 10.1103/physrevb.42.9194] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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309
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Kuhn M, Prévost MC, Mounier J, Sansonetti PJ. A nonvirulent mutant of Listeria monocytogenes does not move intracellularly but still induces polymerization of actin. Infect Immun 1990; 58:3477-86. [PMID: 2172164 PMCID: PMC313686 DOI: 10.1128/iai.58.11.3477-3486.1990] [Citation(s) in RCA: 58] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Listeria monocytogenes has the capacity to penetrate and multiply within professional and nonprofessional phagocytic cells, such as the Caco-2 human enterocytelike cell line. It was shown recently that shortly after listeriae have been phagocytosed, the phagosomal membrane is dissolved, probably by the action of the bacterial cytolysin listeriolysin O. The listeriae, which are then lying obviously free in the cytoplasm, become surrounded by a coat of actin filaments within a few hours. Once formed, this layer of actin filaments is reorganized in an as yet unknown way to form polar tails, which seem to be associated to the generation of listerial movement inside the cytoplasm and in intercellular spread. By using transposon Tn916 mutagenesis, a bank of L. monocytogenes mutants was generated and subsequently screened by the plaque assay system in order to select an intracellular, nonmotile mutant of L. monocytogenes. One such mutant was identified. This mutant, called L. monocytogenes M117 Imt- (for intracellular motility), like the wild type, induced actin polymerization but was not able to rearrange the actin coat to generate movement and as a result remained entrapped within the actin cloud. In a mouse virulence assay, this strain was significantly reduced in virulence. L. monocytogenes M117 is the first example to date of a Listeria mutant which is still hemolytic and invasive but reduced in virulence.
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310
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Sham TK, Yiu YM, Kuhn M, Tan KH. Electronic structure of ordered and disordered Cu3Au: The behavior of the Au 5d bands. PHYSICAL REVIEW. B, CONDENSED MATTER 1990; 41:11881-11886. [PMID: 9993639 DOI: 10.1103/physrevb.41.11881] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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311
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Kuhn M, Gross-Fengels W, Neufang KF, Krüger J. [The importance of i.v. DSA in the diagnosis of acute pulmonary embolism]. RONTGEN-BLATTER; ZEITSCHRIFT FUR RONTGEN-TECHNIK UND MEDIZINISCH-WISSENSCHAFTLICHE PHOTOGRAPHIE 1990; 43:188-94. [PMID: 2189201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The high mortality rate of pulmonary embolism requires rapid and rational diagnosis especially with regard to the necessary decision about the best possible treatment. Analysis of data published in the literature, and of our own data, show that angiography of the a. pulmonalis according to the i.v. DSA technique is of central importance. This involves fewer hazards than conventional pulmonalis angiography while being comparatively satisfactory in respect of reliability of the results (more than 90%). It is, therefore, a safe basis for deciding on the appropriate treatment: lysis or surgery.
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312
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Abstract
A quasi-experimental trial, yielding 30 data points per system, was carried out to investigate the influence of component parts on the overall performance of urinary sheath systems. Information was obtained on the effect of changing both the sheath and leg-bag. Data from the trial was supported by accurate stock-taking analysis over two periods of 4 weeks' duration when alternative systems were used in a clinical setting. Results suggest that leg-bag design profoundly influences the performance of urinary sheaths. A significant difference in the performance of two urinary sheaths in the presence of the same leg-bag was also observed. The significance of the findings for nursing practice is discussed since the optimum performance, from the components tested, was a 'hybrid' system. A continuing line of investigation is suggested whereby improvements in the composition of urinary sheath systems could be made from nursing research.
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313
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Bode SM, Kuhn M, Förstermann U. Chemotactic peptide FMLP contracts human coronary arteries via cyclooxygenase products. THE AMERICAN JOURNAL OF PHYSIOLOGY 1990; 258:H848-53. [PMID: 2107761 DOI: 10.1152/ajpheart.1990.258.3.h848] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The chemotactic peptide N-formyl-L-methionyl-L-leucyl-L-phenylalanine (FMLP) is a constrictor of bronchial smooth muscle. Recently it has also been shown to contract rabbit coronary arteries by an unknown mechanism. This prompted us to investigate whether the chemotactic peptide has an effect on the tone of human coronary arteries obtained during heart transplantation. FMLP was found to be a potent and efficacious myotropic agent on strips of human coronary artery. Contractions were generally transient and subject to tachyphylaxis. The FMLP-induced vasoconstriction was not dependent on the presence of endothelial cells. The response was unaffected by the histamine H1-antagonist diphenhydramine or the antagonist of peptido-leukotrienes FPL 55712. However, the contractions were completely abolished in the presence of the fatty acid cyclooxygenase inhibitors aspirin or indomethacin. Stimulation of rings of human coronary artery with FMLP resulted in a marked production of prostaglandin (PG)F2 alpha, a smaller production of PGD2, and a slight increase in thromboxane B2. All these prostanoids constricted the artery, but the stable thromboxane mimetic U44069 was 100 times more potent than PGF2 alpha or PGD2. These data indicate that FMLP activates cells of unknown identity in the adventitia or media of human coronary arteries to produce a mixture of vasoconstrictor cyclooxygenase products. These compounds are likely to mediate the myotropic effect of FMLP on this artery. The mechanism may participate in the pathogenesis of some forms of coronary vasospasm.
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314
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Kuhn M, Böger P. Studies on the light-induced loss of the D1 protein in photosystem-II membrane fragments. PHOTOSYNTHESIS RESEARCH 1990; 23:291-296. [PMID: 24419652 DOI: 10.1007/bf00034859] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/1988] [Accepted: 09/17/1989] [Indexed: 06/03/2023]
Abstract
PS II membrane fragments produced from higher plant thylakoids by Triton X-100 treatment exhibit strong photoinhibition and concomitant fast degradation of the D1 protein. Involvement of (molecular) oxygen is necessary for degradation of the D1 protein.The herbicides atrazine and diuron, but not ioxynil, partly protect the D1 protein against degradation. Binding of atrazine to the D1 protein is necessary to protect the D1 polypeptide, as shown with PS II membrane fragments from an atrazine-resistant biotype of Chenopodium album which are protected by diuron not by atrazine.
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315
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Kuhn M, Nef W, Gartmann J, Hartmann G. [Non-healing foot wound]. SCHWEIZERISCHE RUNDSCHAU FUR MEDIZIN PRAXIS = REVUE SUISSE DE MEDECINE PRAXIS 1989; 78:1319-22. [PMID: 2587883] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
A young man from Sri Lanka developed a suppurative chronic wound on the right foot after a minor trauma. In spite of several surgical interventions a closure of the ulcer did not occur. Only six months later after serious miliary tuberculosis had developed the correct diagnosis was established and tuberculostatic therapy initiated. This manifestation of tuberculosis--rare in recent times--is reviewed. Emphasis is placed on the causal relation between trauma and reactivation of tuberculosis as well as the pathogenesis of secondary miliary tuberculosis.
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316
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Kuhn M. [What is your diagnosis? Mature teratoma of the anterior mediastinum]. SCHWEIZERISCHE RUNDSCHAU FUR MEDIZIN PRAXIS = REVUE SUISSE DE MEDECINE PRAXIS 1989; 78:1243-4. [PMID: 2814109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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317
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Abstract
Pleural fluid eosinophilia is rare and is commonly considered as an indicator of good prognosis. In a series of 224 patients, pleural eosinophilia was present in four of 84 malignant cases; however, the incidence of malignancy in the presence of pleural eosinophilia was 0.40, being explained by a relatively high prevalence of malignancies in the population studied. Although pleural eosinophilia is rare in malignant effusions, it cannot be considered as indicating a good prognosis without taking into consideration the local prevalence of malignancies.
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318
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Pethig R, Kuhn M, Payne R, Adler E, Chen TH, Jaffe LF. On the dissociation constants of BAPTA-type calcium buffers. Cell Calcium 1989; 10:491-8. [PMID: 2515001 DOI: 10.1016/0143-4160(89)90026-2] [Citation(s) in RCA: 115] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
We have determined or redetermined the calcium dissociation constants of seven BAPTA-type buffers with KD's in the range from 0.4 microM to about 20 mM in 300 mM KCl. These include four newly synthesized ones: 5-nitro BAPTA; 5,5'-dinitro BAPTA; 5-methyl-5'-nitro BAPTA; and 5-methyl-5'-formyl BAPTA. Moreover, we tabulate dissociation constants or KD's for BAPTA and eleven BAPTA-type buffers, compare most of them with an empirical curve based upon so-called Hammett values, and predict KD's for several still unsynthesized but potentially valuable buffers.
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319
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Eigenmann AK, Kuhn M. [Pulmonary eosinophilic infiltration with pneumothorax during trimipramine treatment]. Dtsch Med Wochenschr 1989; 114:1320-3. [PMID: 2766955 DOI: 10.1055/s-2008-1066760] [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: 01/02/2023]
Abstract
Three weeks after starting treatment with the antidepressant trimipramine a 55-year-old man developed increasing cough, fatigue and lack of appetite. The blood count revealed marked eosinophilia (15%) and the chest X-ray showed bilateral pulmonary infiltrates. Later a left spontaneous pneumothorax occurred. When trimipramine was discontinued (as the suspected cause of the described changes) the symptoms quickly subsided and the infiltrate as well as the eosinophilia quickly disappeared.
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320
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Kuhn M, Kreysa G. Modelling of gas-evolving electrolysis cells. III. TheiR drop at gas-evolving electrodes. J APPL ELECTROCHEM 1989. [DOI: 10.1007/bf01320647] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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321
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Kuhn M. [What is your diagnosis? Chronic eosinophilic pneumonia]. SCHWEIZERISCHE RUNDSCHAU FUR MEDIZIN PRAXIS = REVUE SUISSE DE MEDECINE PRAXIS 1989; 78:887-8. [PMID: 2799161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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322
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Fehr T, Kuhn M, Loosli HR, Ponelle M, Boelsterli JJ, Walkinshaw MD. 2-Epimutalomycin and 28-epimutalomycin, two new polyether antibiotics from Streptomyces mutabilis. Derivatization of mutalomycin and the structure elucidation of two minor metabolites. J Antibiot (Tokyo) 1989; 42:897-902. [PMID: 2737949 DOI: 10.7164/antibiotics.42.897] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
A number of derivatives of mutalomycin (1), a naturally occurring polyether antibiotic, have been synthesized. In the desulfurization reaction of the ethylthio derivative (5) of mutalomycin (1) with Raney-nickel we observed an unusual course of the reaction, namely the introduction of a hydroxy group instead of the usual exchange against hydrogen, leading to two reaction products, mutalomycin (1) and 28-epimutalomycin (3). The structure of 3 and 2-epimutalomycin (2), both minor metabolites from the mutalomycin fermentation, were elucidated by X-ray analysis.
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323
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Yersin B, Kuhn M. [Pulmonary complications and acid-base disorders in liver diseases]. SCHWEIZERISCHE MEDIZINISCHE WOCHENSCHRIFT 1989; 119:595-600. [PMID: 2662399] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Liver diseases are frequently associated with pulmonary complications and acid-base disorders, alterations which are frequently overlooked and thus undiagnosed in these patients. Among the respiratory abnormalities, mention should be made of the numerous functional and anatomic alterations responsible for arterial desaturation, the frequent chronic hyperventilation and the rare plexiform pulmonary hypertension. Acid-base disorders, especially respiratory alkalosis and metabolic alkalosis, are common. These conditions have a number of therapeutic implications since some of them play an important role in the pathophysiology of hepatic encephalopathy. The complications and their specific diagnostic features are reviewed and some therapeutic proposals are made.
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324
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325
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Kuhn M, Goebel W. Identification of an extracellular protein of Listeria monocytogenes possibly involved in intracellular uptake by mammalian cells. Infect Immun 1989; 57:55-61. [PMID: 2491841 PMCID: PMC313040 DOI: 10.1128/iai.57.1.55-61.1989] [Citation(s) in RCA: 213] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Mutants of Listeria monocytogenes were recently isolated which are impaired in the synthesis of a major extracellular protein (p60). As shown in this investigation, the p60 mutants have lost the capability of invading nonprofessional phagocytic 3T6 mouse fibroblast cells. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of supernatant proteins of these mutants indicated that no other extracellular protein was altered in these mutants. The p60 mutants formed long cell chains which disaggregated to normal-sized single bacteria upon treatment with partially purified p60. These disaggregated bacterial cells were able to invade 3T6 cells. Physical disruption of the cell chains by ultrasonication produced similar single cells which were, however, noninvasive. Treatment of these ultrasonicated mutant cells with wild-type p60 restored their ability to invade 3T6 cells.
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326
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de Ancos E, Kuhn M, Portmann L. [Frequent problems with non-steroidal antirheumatic agents (NSAID) in old age]. SCHWEIZERISCHE MEDIZINISCHE WOCHENSCHRIFT 1988; 118:1808-9. [PMID: 3206227] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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327
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Vogt P, Goy JJ, Kuhn M, Leuenberger P, Kappenberger L. Single versus double chamber rate responsive cardiac pacing: comparison by cardiopulmonary noninvasive exercise testing. Pacing Clin Electrophysiol 1988; 11:1896-901. [PMID: 2463564 DOI: 10.1111/j.1540-8159.1988.tb06326.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
A new double chamber rate responsive cardiac pacemaker (DDDMR) has been implanted in seven patients (four males and three females) with a mean age of 62 years. Indication for pacemaker treatment was complete AV block in two patients, complete AV block associated to sinus node disease in three patients and sinus node disease alone in two patients. Six patients underwent two maximal stress tests on a cycloergometer performed twice randomly starting with VVIMR or DDDMR. Basic work load of 50 watts was increased by steps of 25 watts every 2 minutes. Heart rate, respiratory frequency, blood pressure, exercise duration, maximal charge developed, oxygen consumption, rate pressure product, efficiency and Borg scale were compared. Our results show a general trend but no significant differences between all the measured parameters except for efficiency which was significantly higher with DDDMR. These results prove a slight improvement of cardiopulmonary performance in DDDMR pacing compared to VVIMR and also confirm the importance of atrial contribution to cardiac output on exercise.
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328
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Hussain Z, Kuhn M, Lannigan R, Austin TW. Microbiological investigation of an outbreak of bacteraemia due to Streptococcus faecalis in an intensive care unit. J Hosp Infect 1988; 12:263-71. [PMID: 2907332 DOI: 10.1016/0195-6701(88)90068-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
An increased incidence of bacteraemia due to Streptococcus faecalis in a Critical Care and Trauma Centre (CCTC) during November 1985 prompted investigation. During the epidemic 21 blood cultures from five CCTC patients were positive for S. faecalis. A point prevalence culture survey revealed two more strains from wounds from two of these five patients. Fifteen strains from blood cultures and the two strains from wound sites were further characterized by conventional biotyping methods and susceptibility patterns, but they could not be differentiated from 40 unrelated control strains by these methods. The API-20S and the API-ZYM systems, however, were able to distinguish the outbreak isolates from the control strains. This investigation supports the hypothesis that S. faecalis is capable of causing cross-infection, and it may be necessary to characterize enterococci beyond routine tests to identify an outbreak due to this organism.
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329
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Abstract
The ECG diagnosis of myocardial infarction in the setting of bundle branch block is one that most physicians find difficult and that many erroneously believe to be impossible. Two case reports of a patient with right bundle branch block and of a patient with left bundle branch block are presented to illustrate instances in which the ECG diagnosis of myocardial infarction was both possible and essential. Methods for detecting ECG changes that indicate acute myocardial injury in the patient with bundle branch block are presented and applied to these cases.
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330
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Goldfarb CR, Ongseng F, Kuhn M, Metzger T. Non-skeletal accumulation of bone seeking agents: pelvis. Semin Nucl Med 1988; 18:159-61. [PMID: 3388051 DOI: 10.1016/s0001-2998(88)80007-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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331
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Poniewierski M, Barthels M, Kuhn M, Poliwoda H. [Effectiveness of low molecular weight heparin (Fragmin) in the prevention of thromboembolism in internal medicine patients. A randomized double-blind study]. MEDIZINISCHE KLINIK (MUNICH, GERMANY : 1983) 1988; 83:241-5, 278. [PMID: 2837625] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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332
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Goebel W, Kathariou S, Kuhn M, Sokolovic Z, Kreft J, Köhler S, Funke D, Chakraborty T, Leimeister-Wächter M. Hemolysin from Listeria--biochemistry, genetics and function in pathogenesis. Infection 1988; 16 Suppl 2:S149-56. [PMID: 3138189 DOI: 10.1007/bf01639739] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Thiol-activated hemolysins (listeriolysins) from Listeria monocytogenes (Sv4b) and Listeria ivanovii were purified to homogeneity. The N-terminal amino acid sequences of the 58 kDa listeriolysin of L. ivanovii and of a 24 kDa protein which may represent the CAMP-factor of L. ivanovii were determined. Antibodies raised against the L. ivanovii listeriolysin and anti-streptolysin O antibodies were used in Western blot analyses to detect listeriolysin(s) in virulent and avirulent Listeria strains. It was found that all virulent strains of L. monocytogenes synthesize and secrete listeriolysin (Mr 58-59 kDa), albeit in significantly variable quantities. No protein cross-reaction with anti-listeriolysin antibodies or anti-streptolysin O-antibodies was present in the supernatant of Listeria innocua, Listeria welshimeri, Listeria grayi and Listeria murrayi strains. Furthermore, the avirulent but hemolytic Listeria seeligeri did not cross-react with these antibodies. In a L. monocytogenes (strain EGD) gene bank constructed in Escherichia coli two types of hemolytic clones were identified. The first type carried recombinant plasmids with a common 2.0 kb fragment coding for a 23 kDa protein. This hemolytic activity was not activated by DTT and the 23 kDa protein did not cross react with anti-listeriolysin or anti-streptolysin antibodies. The other type of hemolytic clones was detected by using anti-streptolysin O antibodies to screen the gene bank. Some of these clones synthesized a protein of 61 kDa which cross reacted with anti-streptolysin O (or anti-listeriolysin) antibodies. By transposon Tn916 mutagenesis of L. monocytogenes two types of nonhemolytic mutants were obtained. Type I produced no extracellular protein that cross reacted with anti-listeriolysin (or anti SLO) antibodies.(ABSTRACT TRUNCATED AT 250 WORDS)
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Keljo DJ, Kuhn M, Smith A. Acidification of endosomes is not important for the entry of rotavirus into the cell. J Pediatr Gastroenterol Nutr 1988; 7:257-63. [PMID: 2832585 DOI: 10.1097/00005176-198803000-00016] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Rotavirus causes enteritis in both man and animals. The mechanism by which this protein-enveloped virus enters the cell to initiate infection is not known. Many viruses depend on the acidification of endosomes for entry into the cell. We studied the importance of the acidification of endosomes for the initiation of two early phases of rotavirus infection, virus RNA and peptide synthesis. Monensin, nigericin, chloroquine and ammonium chloride at a variety of concentrations caused no specific inhibition of virus RNA or peptide synthesis. We conclude that the acidification of endosomes is not important for the entry of rotavirus into the cell.
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334
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Kuhn M, Jendrossek D, Fründ C, Steinbüchel A, Schlegel HG. Cloning of the Alcaligenes eutrophus alcohol dehydrogenase gene. J Bacteriol 1988; 170:685-92. [PMID: 2828319 PMCID: PMC210709 DOI: 10.1128/jb.170.2.685-692.1988] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Mutants of Alcaligenes eutrophus which are altered with respect to the utilization of 2,3-butanediol and acetoin were isolated after transposon mutagenesis. The suicide vehicle pSUP5011 was used to introduce the drug resistance transposable element Tn5 into A. eutrophus. Kanamycin-resistant transconjugants of the 2,3-butanediol-utilizing parent strains CF10141 and AS141 were screened for mutants impaired in the utilization of 2,3-butanediol or acetoin. Eleven mutants were negative for 2,3-butanediol but positive for acetoin; they were unable to synthesize active fermentative alcohol dehydrogenase protein (class 1). Forty mutants were negative for 2,3-butanediol and for acetoin (class 2). Tn5-mob was also introduced into a Smr derivative of the 2,3-butanediol-nonutilizing parent strain H16. Of about 35,000 transconjugants, 2 were able to grow on 2,3-butanediol. Both mutants synthesized the fermentative alcohol dehydrogenase constitutively (class 3). The Tn5-labeled EcoRI fragments of genomic DNA of four class 1 and two class 3 mutants were cloned from a cosmid library. They were biotinylated and used as probes for the detection of the corresponding wild-type fragments in a lambda L47 and a cosmid gene bank. The gene which encodes the fermentative alcohol dehydrogenase in A. eutrophus was cloned and localized to a 2.5-kilobase (kb) SalI fragment which is located within a 11.5-kb EcoRI-fragment. The gene was heterologously expressed in A. eutrophus JMP222 and in Pseudomonas oxalaticus. The insertion of Tn5-mob in class 3 mutants mapped near the structural gene for alcohol dehydrogenase on the same 2.5-kb SalI fragment.
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Wagner W, Kuhn M, Goebel W. Active and inactive forms of hemolysin (HlyA) from Escherichia coli. BIOLOGICAL CHEMISTRY HOPPE-SEYLER 1988; 369:39-46. [PMID: 3279976 DOI: 10.1515/bchm3.1988.369.1.39] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The HlyA protein (Mr 110 kDa) which is the gene product of the hlyA gene encoded by the hemolysin determinant of Escherichia coli (Goebel, W. & Hedgpeth, J. (1982) J. Bacteriol. 151, 1290-1298) was observed to accumulate in the culture supernatant (in the presence of the three other Hly proteins HlyC, B and D) throughout the active growth cycle. However, the amount of extracellular HlyA protein did not correlate with the external hemolytic activity, which declined when the cells entered the stationary phase. External hemolytic activity was highly sensitive to phospholipase C and to ultrasonication. The size of the HlyA protein on SDS-PAGE was not changed by these treatments although the hemolytic activity was entirely abolished. On a polyacrylamide gel containing 2M urea but only 0.1% SDS hemolytically active HlyA migrated slightly ahead of the inactive HlyA suggesting that HlyA is more negatively charged than HlyA. Active hemolysin from unconcentrated hemolytic supernatants migrated on Sephacryl S-400 and on glycerol gradients as large complexes. Analysis of the hemolytically active fractions on SDS-PAGE yielded in both cases only HlyA (110 kDA) as major protein. An internal hemolytic activity appeared in most Escherichia coli K-12 strains in the stationary phase which was independent of the presence of HlyA or any other Hly gene product. This hemolytic activity which reached in some strains about 10% of the level determined by the hly genes was sensitive to proteinase K and disappeared upon shift of the cells to the logarithmic phase.
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Kuhn M, Kathariou S, Goebel W. Hemolysin supports survival but not entry of the intracellular bacterium Listeria monocytogenes. Infect Immun 1988; 56:79-82. [PMID: 3121515 PMCID: PMC259237 DOI: 10.1128/iai.56.1.79-82.1988] [Citation(s) in RCA: 150] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
The gram-positive bacterium Listeria monocytogenes is a facultative intracellular pathogen. The only known property of L. monocytogenes which has been shown to be involved in virulence is a hemolysin, listeriolysin (J. L. Gaillard, P. Berche, and P. Sansonetti, Infect. Immun. 52:50-55, 1986; S. Kathariou, P. Metz, H. Hof, and W. Goebel, J. Bacteriol. 169:1291-1297, 1987). Using our previously obtained transposon Tn916-induced hemolysin-negative mutants of L. monocytogenes Sv1/2a (Mackaness strain), we demonstrated that the loss of hemolysin reduced significantly the rate of survival of the bacteria in mouse peritoneal macrophages but did not reduce their uptake. It was further shown that virulent L. monocytogenes strains could invade the mouse embryo fibroblast 3T6 cell line, i.e., mammalian cells which are nonprofessional phagocytes. This uptake was inhibited by cytochalasin B and hence seems to be accomplished by parasite-induced endocytosis. Hemolysin was not essential for this step. Strains of other Listeria species could not efficiently penetrate the 3T6 cells.
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Chakraborty T, Kathariou S, Hacker J, Hof H, Huhle B, Wagner W, Kuhn M, Goebel W. Molecular analysis of bacterial cytolysins. REVIEWS OF INFECTIOUS DISEASES 1987; 9 Suppl 5:S456-66. [PMID: 2825323 DOI: 10.1093/clinids/9.supplement_5.s456] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Results of molecular and pathogenic studies of three different bacterial hemolysins (cytolysins) are presented. These exoproteins derive from the two gram-negative bacteria Escherichia coli and Aeromonas hydrophila and from the gram-positive pathogen Listeria monocytogenes. The hemolysin of E. coli is determined by an 8-kilobase (kb) region that includes four clustered genes (hlyC, hlyA, hlyB, and hlyD). This hemolysin determinant is part either of large transmissible plasmids or of the chromosome. The genes located chromosomally are found predominantly in E. coli strains that can cause pyelonephritis and/or other extraintestinal infections. A detailed analysis of the chromosomal hyl determinants of one nephropathogenic E. coli strain revealed the existence of specific, large chromosomal insertions 75 kb and 100 kb in size that carry the hly genes but that also influence the expression of other virulence properties, i.e., adhesion and serum resistance. The direct involvement of E. coli hemolysin in virulence could be demonstrated in several model systems. The genetic determinants for hemolysin (cytolysin) formation in A. hydrophila (aerolysin) and L. monocytogenes (listeriolysin) are less complex. Both cytolysins seem to be encoded by single genes, although two loci (aerB and aerC) that affect the expression and activity of aerolysin have been identified distal and proximal to the structural gene for aerolysin (aerA). Cytolysin-negative mutants of both bacteria were obtained by site-specific deletion and/or transposon mutagenesis. These mutants show a drastic reduction in the virulence of the respective bacteria.
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Kuhn M, Fitting JW, Leuenberger P. Acute pulmonary edema caused by venous air embolism after removal of a subclavian catheter. Chest 1987; 92:364-5. [PMID: 3475195 DOI: 10.1378/chest.92.2.364] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
A 17-year-old boy, who had received chemotherapy for a relapse of acute myelogenous leukemia, manifested a brief loss of consciousness and acute pulmonary edema immediately after the removal of a triple-lumen subclavian catheter. This complication was attributed to a venous air embolism.
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Kuhn M, Flury G, Germann D, Gartmann J. [Radiological lung changes during an influenza epidemic in 2 schools for Army recruits]. SCHWEIZERISCHE RUNDSCHAU FUR MEDIZIN PRAXIS = REVUE SUISSE DE MEDECINE PRAXIS 1987; 76:547-50. [PMID: 3629055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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Kathariou S, Köhler S, Kuhn M, Goebel W. Identification of the virulence components of Listeria monocytogenes by transposon (Tn916) mutagenesis. ACTA ACUST UNITED AC 1987. [DOI: 10.1016/0769-2609(87)90204-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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341
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Grabbe E, Maas R, Heller M, Denkhaus H, Kooijman H, Kuhn M, Bücheler E. [Magnetic resonance tomographic studies at 2.0 Tesla. Evaluation of clinically relevant parameters]. ROFO-FORTSCHR RONTG 1986; 145:464-70. [PMID: 2430319 DOI: 10.1055/s-2008-1048971] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
After having used a 2 Tesla prototype whole body scanner for about one and a half years, it is now possible to comment on the clinical value of high field strengths. The methods and techniques employed are described. The problems arising from high field strengths are discussed and their effect on clinical diagnosis is indicated.
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Caduff B, Kuhn M, Hartmann G. [Chronic bromide poisoning. A rare disease picture today]. SCHWEIZERISCHE RUNDSCHAU FUR MEDIZIN PRAXIS = REVUE SUISSE DE MEDECINE PRAXIS 1986; 75:553-5. [PMID: 3715277] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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343
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Kuhn M. Nurses as advocates. Interview by Judith Paquet. J Gerontol Nurs 1986; 12:44. [PMID: 3633946] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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344
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Schön H, Kuhn M, Allemann J, Ratti R. [Traumatic myocardial infarct. Report of 3 cases]. SCHWEIZERISCHE MEDIZINISCHE WOCHENSCHRIFT 1986; 116:218-21. [PMID: 3952479] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Three patients aged 52, 22 and 29 years, without known previous heart disease, sustained acute myocardial infarction due to blunt chest trauma. A 52-year-old man without a history of heart disease sustained an acute non-transmural lateral myocardial infarction following blunt chest trauma during a sledging party. No coronary arteriography was performed. The clinical course during follow-up of 3 1/2 years was uncomplicated. A 22-year-old, previously asymptomatic man developed acute transmural anteroseptal infarction after a motor-cycle accident. Seven days later he died suddenly after an uncomplicated initial course. The autopsy demonstrated a complete rupture of the proximal left anterior descending artery with periarterial hemorrhage, compression of this artery by the hemorrhage and luminal thrombosis distal to the rupture. No sign of preexisting atherosclerotic coronary disease was found. A 29-year-old man admitted to the hospital after blunt chest trauma during a football game developed an acute transmural inferior infarction with an uncomplicated clinical course. Seven months later coronary arteriography demonstrated a 40% obstructive lesion of the right coronary artery, compatible with thrombosis and subsequent recanalization.
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345
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Boerlin V, Maeglin B, Hägler W, Kuhn M, Nüesch E. Analgesic activity of propyphenazone in patients with pain following oral surgery. Eur J Clin Pharmacol 1986; 31:127-31. [PMID: 3492378 DOI: 10.1007/bf00606648] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The acute analgesic effect of single oral doses of 150 and 300 mg propyphenazone, 1000 mg acetylsalicylic acid (ASA) and placebo was investigated in 210 patients with pain following dental surgery. At most time points over the 3-hour observation period all the active medications had a significantly greater analgesic effect than placebo according to all the methods of pain assessment used. Both doses of propyphenazone reached their peak activity sooner than ASA, and their duration of action tended to be shorter. On a per milligram basis, the relative analgesic potency of propyphenazone was about twice that of ASA. All test substances were well tolerated. Side effects, such as tiredness, nausea, headache, dizziness etc., were reported by less than 20% of the patients. The nature of the adverse reactions was similar for all medications, and as they were recorded most frequently after placebo, they cannot therefore be definitely ascribed to one or the other of the active test substances.
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Kuhn M, Widder W, Gartmann J, Hartmann G. [Acute hypercalcemia syndrome in sarcoidosis]. SCHWEIZERISCHE MEDIZINISCHE WOCHENSCHRIFT 1985; 115:1365-7. [PMID: 3840913] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
In a 26-year-old patient admitted to the emergency ward with acute abdomen, all the symptoms--nausea, vomiting, indeterminate abdominal pain, constipation, renal failure, polyuria and polydipsia--could be explained by calcium intoxication syndrome. Investigation revealed generalized sarcoidosis. Under medical treatment with prednisone all the pathologic findings rapidly regressed. The pathogenesis of hypercalcemia in sarcoidosis, and particularly the disorder of vitamin D metabolism with raised levels of 1,25-dihydroxycholecalciferol, are discussed.
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347
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Brunner W, Kuhn M, Hartmann G. [Coumarin necrosis. A rare severe complication of oral anticoagulation]. SCHWEIZERISCHE RUNDSCHAU FUR MEDIZIN PRAXIS = REVUE SUISSE DE MEDECINE PRAXIS 1985; 74:141-3. [PMID: 3975527] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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348
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Kuhn M. For an end to ageism. HEALTH & MEDICINE : JOURNAL OF THE HEALTH AND MEDICINE POLICY RESEARCH GROUP 1985; 2:34-5. [PMID: 10270160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
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349
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350
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Kuhn M, Steinbüchel A, Schlegel HG. Hydrogen evolution by strictly aerobic hydrogen bacteria under anaerobic conditions. J Bacteriol 1984; 159:633-9. [PMID: 6378884 PMCID: PMC215690 DOI: 10.1128/jb.159.2.633-639.1984] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
When strains and mutants of the strictly aerobic hydrogen-oxidizing bacterium Alcaligenes eutrophus are grown heterotrophically on gluconate or fructose and are subsequently exposed to anaerobic conditions in the presence of the organic substrates, molecular hydrogen is evolved. Hydrogen evolution started immediately after the suspension was flushed with nitrogen, reached maximum rates of 70 to 100 mumol of H2 per h per g of protein, and continued with slowly decreasing rates for at least 18 h. The addition of oxygen to an H2-evolving culture, as well as the addition of nitrate to cells (which had formed the dissimilatory nitrate reductase system during the preceding growth), caused immediate cessation of hydrogen evolution. Formate is not the source of H2 evolution. The rates of H2 evolution with formate as the substrate were lower than those with gluconate. The formate hydrogenlyase system was not detectable in intact cells or crude cell extracts. Rather the cytoplasmic, NAD-reducing hydrogenase is involved by catalyzing the release of excessive reducing equivalents under anaerobic conditions in the absence of suitable electron acceptors. This conclusion is based on the following experimental results. H2 is formed only by cells which had synthesized the hydrogenases during growth. Mutants lacking the membrane-bound hydrogenase were still able to evolve H2. Mutants lacking the NAD-reducing or both hydrogenases were unable to evolve H2.
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