Publications by authors named "Engelhart M"

38 Publications

Ketanserin in the treatment of Raynaud's phenomenon associated with generalized scleroderma.

Authors:
M Engelhart

Br J Dermatol 1988 Dec;119(6):751-4

Department of Dermatology, Rigshospital, Copenhagen, Denmark.

The efficacy of the 5-HT-2-receptor antagonist, ketanserin, in the treatment of Raynaud's phenomenon was assessed in a double-blind, placebo-controlled, crossover trial in nine patients with generalized scleroderma (GS). Each patient received ketanserin 20 mg or placebo three times a day in the 1st week and 40 mg ketanserin or placebo three times a day for the remaining 4 weeks, and was then crossed over for 5 weeks. Measurements were made of finger blood pressure and flow during a cold challenge test and patients recorded numbers of Raynaud's attacks. No significant improvement was found in reactions to cold provocation or in numbers of Raynaud's attacks during ketanserin treatment, but intolerable side-effects were common. Interactions with concomitant medication might be a possible explanation for this. We conclude that ketanserin in the dose given, is not effective in the treatment of Raynaud's phenomenon in GS.
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http://dx.doi.org/10.1111/j.1365-2133.1988.tb03498.xDOI Listing
December 1988

The local regulation of blood flow evaluated simultaneously by 133-xenon washout and laser Doppler flowmetry.

J Invest Dermatol 1988 Nov;91(5):451-3

Department of Dermatology, University of Copenhagen Rigshospital, Denmark.

The laser Doppler flowmeter and the 133-Xenon washout techniques of measuring cutaneous blood flow were compared for measuring the vasoconstrictor response of the hand during orthostatic maneuvres. Important discrepancies were detected for the two methods. When the hand was lowered by 40 cm a 40% decrease in blood flow was detected by the 133-Xenon method, while a 60% decrease was seen by the laser Doppler technique. Lowering the hand by 50 cm resulted in no further blood flow decrease when using the 133-Xenon method, but an 80% blood flow decrease was recorded with the laser Doppler method. A marked decrease in blood flow was recorded by the laser Doppler technique in hands that were sympathectomized or a hand that was subjected to a nerve blockade, strategies which should eliminate the orthostatic vasoconstrictor response of superficial cutaneous vessels. The 133-Xenon technique did not detect any blood flow changes in hands without sympathetic tone. We found the laser Doppler flowmetry technique unsatisfactory for measurement of blood flow changes that occur in nutritional vessels as this method measures total skin blood flow including non-capillary vessels.
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http://dx.doi.org/10.1111/1523-1747.ep12476572DOI Listing
November 1988

Raynaud's phenomenon: blood supply to fingers during indirect cooling, evaluated by laser Doppler flowmetry.

Clin Physiol 1986 Dec;6(6):481-8

The effect of indirect cooling on finger-tip blood flow patterns were recorded in 31 patients suffering from Raynaud's phenomenon. Fifteen were suffering from generalized scleroderma with acrosclerosis (GS), and 16 from primary Raynaud's phenomenon (PR), and were compared to 13 healthy controls without cold sensitivity. Finger blood flow (FBF) was monitored by a laser Doppler flowmeter. Resting blood flow values were significantly lower in patients compared to controls. After two min of body cooling no difference could be observed in relative flow decrease between patients and controls or between PR and GS, but after 10 min of body cooling, relative flow decrease tended to be more pronounced in GS than in PR. Only in GS was the zero flow situation observed. During the resting condition, skin vessel vasomotion was observed as rhythmical variations in the blood flow of 5-10 cycles per minute. These seemed to be preserved in patients and in chronically sympathectomized patients, and could not be abolished by nerve blockade of the finger. The influence from sympathetic vasomotor fibres on FBF could be observed during cooling as irregular coarse flow fluctuations. This was observed in both patients and controls but not in the chronically sympathectomized patients and disappeared after nerve blockade of the finger. Finger temperature was measured simultaneously during body cooling, but significant changes were observed only in normals and PR.(ABSTRACT TRUNCATED AT 250 WORDS)
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http://dx.doi.org/10.1111/j.1475-097x.1986.tb00781.xDOI Listing
December 1986

The blood supply to fingers during Raynaud's attack: a comparison of laser-Doppler flowmetry with other techniques.

Clin Physiol 1985 Oct;5(5):447-53

Responses to combined body and finger cooling were recorded by laser-Doppler flowmetry, Xenon-113 washout and strain-gauge plethysmography in 22 patients (seven patients with primary Raynaud's phenomenon (PR) and 15 with generalized scleroderma (GS] and nine healthy, warm-handed subjects. Finger systolic blood-pressure decreased to zero in 100% of the patients, after body and finger cooling as measured with strain-gauge plethysmography. With the laser-Doppler flowmeter a low-positive blood-pressure was registered in two patients. The duration of a Raynaud's attack was found to vary from 0.5 to greater than 5 minutes as observed by the laser-Doppler flowmeter. Xenon-133 washout from the fingertips, during a zero blood-flow situation, insignificantly deviated from the washout during vascular occlusion. It is concluded that; (1) the elicitation and duration of Raynaud's phenomenon could be clearly observed by laser-Doppler flowmetry; (2) the zero blood-flow observed by laser-Doppler flowmetry could be confirmed by Xenon-133 washout and (3) in GS cases, the laser-Doppler flowmetry seemed more sensitive than the strain-gauge, at extremely low blood flow values.
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http://dx.doi.org/10.1111/j.1475-097x.1985.tb00776.xDOI Listing
October 1985

Evaluation of cutaneous blood flow responses by 133Xenon washout and a laser-Doppler flowmeter.

J Invest Dermatol 1983 Jan;80(1):12-5

A new method for noninvasive measurement of cutaneous blood flow is laser-Doppler flowmetry. The technique is based on the fact that laser light is back-scattered from the moving red blood cells, with Doppler-shifted frequencies; these impulses lead to photodetectors and are converted to flow signals. In this work we used a new system with a low noise level. Comparison was made between this technique and the atraumatic epicutaneous 133Xenon technique for measurement of cutaneous blood flow during reactive hyperemia and orthostatic pressure changes. The laser-Doppler flowmeter seems to measure blood flow in capillaries as well as in arteriovenous anastomoses, while the 133Xe method probably measures only capillary flow. A calibration of the laser-Doppler method against the 133Xe method would appear to be impossible in skin areas where arteriovenous anastomoses are present. The changes in blood flow during reactive hyperemia, orthostatic pressure changes, and venous stasis were found to be parallel as measured by the two methods in skin areas without shunt vessels. The laser-Doppler flowmeter would appear to be a useful supplement to the 133Xe washout method in cutaneous vascular physiology, but it is important to keep in mind that different parameters may be measured.
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http://dx.doi.org/10.1111/1523-1747.ep12530879DOI Listing
January 1983

Laser-Doppler measurement of digital blood flow regulation in normals and in patients with Raynaud's phenomenon.

Acta Derm Venereol 1983 ;63(1):43-7

Finger blood flow was measured continuously by a laser-Doppler flowmeter in normal subjects and in patients suffering from primary or secondary Raynaud's phenomenon. In normals, skin areas with and without arteriovenous anastomoses could be differentiated. Blood flow in areas with shunt vessels decreased after a deep breath but not during venous stasis or the Valsalva maneuvre, while in other skin areas a decrease in blood flow was observed after all three maneuvres, suggesting a dual innervation of nutritional and shunt vessels. In patients with Raynaud's phenomenon (scleroderma) fingertip blood flow reacted in the same way as normal skin without shunt vessels. During direct and indirect cooling, finger blood flow in patients with secondary Raynaud's phenomenon reacted with the same relative reduction as normals but resting blood flow in the patients was significantly decreased and the rewarming period was greatly prolonged. In patients with primary Raynaud's phenomenon an even more prolonged decrease in blood flow was observed after direct or indirect cooling. Defective function of arteriovenous anastomoses is proposed as an explanation of the deviations from normal. A pathophysiological classification of Raynaud's phenomenon may be possible on the basis of the function tests described.
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August 1983

Inhibition of a plasminogen activator from oncogenic virus-transformed mouse cells by rabbit antibodies against the enzyme.

Biochim Biophys Acta 1980 Jun;630(1):146-51

Antisera were raised in rabbits against an electrophoretically pure 48 000 dalton plasminogen activator from mouse cells transformed by an oncogenic virus. The IgG fraction of the antisera inhibited 48 000 dalton mouse plasminogen activators from a variety of sources (neoplastic and nonneoplastic), a 29 00) dalton plasminogen activator from mouse urine and a 48 000 dalton plasminogen activator from rat urine. No inhibition was observed of a 75 000 dalton plasminogen activator extracted from mouse lung, of mouse plasmin or of plasminogen activators from human urine and from oncogenic-virus transformed chicken cells. The IgG antibodies were stronger and more specific inhibitors of the 48 000 dalton mouse plasminogen activator than any previously tested compounds.
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http://dx.doi.org/10.1016/0304-4165(80)90146-4DOI Listing
June 1980
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