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Biomedical subjects

R Beckmann

Publications and source records attributed to R Beckmann.

At least 73 records · Page 4Linked to original sources
PubMed1984

Pharmacokinetics and pharmacodynamics of the stable prostacyclin analogue, ZK 36 374, in the cat.

The pharmacokinetics and the pharmacologic effect on blood pressure and heart rate of ZK 36 374 were studied simultaneously in the unanaesthetized cat following intraarterial injection of 20 micrograms/kg of tritium-labelled drug. After a rapid distribution phase the plasma level of radioactive substances declined with a half-life of 44 min. The disposition of the unchanged drug was biphasic with half-lives of 7 min and 36 min. 1.5 min after injection, the systolic and diastolic blood pressures were depressed by 40 and 57% and the heart rate rose by 18%. The kinetics of the pharmacologic action was biphasic and strictly parallel to the plasma drug level. Accordingly, there was a highly significant (p less than 0.001) logarithmic correlation between the blood pressure depression and the concentration of unchanged ZK 36 374 in the plasma. ZK 36 374 was totally metabolized and excreted nearly equally with urine and feces in the form of more than eight metabolites.

Animals↗
PubMed1984

Early and late administration of a PGI2-analogue, ZK 36 374 (iloprost): effects on myocardial preservation, collateral blood flow and infarct size.

A number of investigations have reported that prostacyclin or prostacyclin analogues protect the ischaemic myocardium when administered early after myocardial ischaemia. Thus far, there are no reports describing whether these substances exert a cardioprotective effect when administered later than 0.5 h after coronary artery occlusion. Adult cats were subjected to acute coronary artery ligation for 5 h and administered the vehicle or ZK 36 374 (iloprost) (1.19 micrograms X kg-1 X min-1), a prostacyclin analogue, beginning at 0.5, 2 or 4 h. Compared with the MI-vehicle cats, ZK 36 374 prevented a decrease in myocardial creatine kinase specific activity, the loss of free amino nitrogen and the fall in percentage bound cathepsin D in the ischaemic area when infusion was started at 0.5 or 2 h (P less than 0.05). In addition ZK 36 374 started at 4 h still showed a significant protective effect against myocardial creatine kinase specific activity and amino nitrogen concentrations but not against cathepsin D. In a separate group of animals, regional myocardial blood flow and late coronary resistance were determined with radioactive labelled 15 +/- 1 micron microspheres. ZK 36 374 consistently reduced late diastolic coronary vascular resistance and increased coronary blood flow in nonischaemic regions of the myocardium (P less than 0.05) but only attenuated the further increase in late coronary resistance in the ischaemic myocardial regions. The infarcted area (NTB-staining) amounted to 9% of the total left ventricle after 5 h and was not reduced by ZK 36 374 (P greater than 0.05). In conclusion, ZK 36 374 exerted a significant biochemical cardioprotective effect when administered to 0.5, 2 or 4 h. The mechanism of cardioprotection does not appear to be due to increased myocardial perfusion but rather to some direct cellular action whose exact nature has yet to be elucidated.

Animals↗
PubMed1983

[Mitral valve insufficiency in coronary heart disease].

On 121 consecutive patients with coronary heart disease coronary angiography and quantitative left ventricular angiography was done with the view to aortocoronary bypass surgery. 24 (20%) had mitral regurgitation (MR) by angiographic criteria, 20 of them had MR grade I/IV, four had MR II/IV. In 23 out of 24 patients with MR quantitative left ventriculography revealed localized contraction disorders. MR was clinically diagnosed in 15 out of 24 patients. In eleven patients (48%) contraction abnormalities were localized in the inferior wall, in five cases (22%) in the anterior wall and in seven cases (30%) both in the anterior and posterior wall. Of the latter group patients with MR showed a significantly lower ejection fraction than patients without MR (p less than 0.05). Furthermore the MR-group showed larger akinetic areas, preferentially located in the inferior segments 0 degrees-240 degrees and in the anterolateral segments 60 degrees-90 degrees. Three vessel disease was more frequent in this group (43%) than in the group without MR (23%). Patients with inferior wall asynergy frequently showed combined stenosis or occlusion of the right and circumflex coronary artery. In conclusion, MR in coronary heart disease is most often associated with localized contraction disorders of the left ventricle; posterior wall infarctions, multiple vessel disease and large akinetic areas are more frequent. However, the hemodynamic significance of MR in patients with chronic myocardial infarction is usually insignificant.

Coronary Angiography↗
PubMed1983

[Electrocardiogram and M-mode echocardiography in the diagnosis of chronic transmural infarct. Correlations and determination of the accuracy of both methods based on quantitative levocardiography].

In a comparative study of 121 consecutive patients who had had coronary angiography for coronary heart disease, the diagnostic informations obtained by M-mode echocardiography and electrocardiography in chronic transmural infarction were compared. Wall excursion by echocardiography did not allow sufficient separation of normal and asynergic segments. Changes in systolic wall thickness, on the other hand, provided satisfactory sensitivity and good specificity in the recognition of segmental contraction disorders: posterior wall thickening of 0.64 and 0.76, respectively, septal thickening of 0.45 and 0.91, respectively. In 53% of patients the ECG and echocardiogram provided findings similar to those by angiography. False-positive findings occurred in 10% of electrocardiograms, 14% of echocardiograms. False-negative findings in the ECG occurred in 13%, in the echocardiogram in 25%. Both methods combined had a specificity of nearly 100% with regard to the diagnosis of posterior-wall and anterior-wall infarction, and a positive predictive value of 0.92 (posterior) and 0.93 (anterior wall infarction). M-mode echocardiography and ECG findings provide reliable diagnosis of both the anterior and posterior wall chronic transmural infarction.

Adult↗
PubMed1983

[Qualitative and quantitative analysis of regional contraction disorders using levocardiograms].

In 74 patients with proven myocardial infarction (typical history and enzymes, diagnostic ECG, and stenosis of the vessel supplying the asynergic region of more than 75%) the results of qualitative analysis of left ventricular cineangiograms were compared to those of quantitative analysis using the radial axis method of Mathes. There was a significant difference in interpretation between the two methods if the physiological movements of the heart were not taken into account in the qualitative analysis. After correction for systolic anterior movement and downward movement of the aortic valve during systole, a mean accuracy of 92% resulted. The radial axis method discriminated well between normokinetic and asynergic wall segments. However, this method proved less useful for the detection of asynergies in the apical, anterobasal, and posterobasal regions. A radial axis angle of between 15 degrees and 20 degrees is considered to be optimal. The quantitative analysis seems to be particularly useful for the interpretation of borderline cases, and should be carried out routinely in addition to the qualitative analysis.

Adult↗
PubMed1983

[Significance of the E point-septum distance for the evaluation of left ventricular function in coronary disease--a study using M-mode echocardiography].

In 121 patients (pts) with angiographically proven coronary artery disease, left ventricular (LV) cineangiograms were quantitatively evaluated. 79 pts showed regional wall abnormalities. In this group the relationship between echocardiographic parameters of global (LV) function (mitral-septal separation, systolic and diastolic diameter, and fractional shortening) and ventriculographic parameters was investigated. Mitral-septal separation showed the best correlation to the angiographic ejection fraction (EF) (r = -0.72). The measurement of this parameter allows the diagnosis of a reduced EF independently of the dilatation of the left ventricle, and is easy to perform and to reproduce. Mitral-septal separation discriminated well between the reference group and all infarction subgroups (posterior wall, anterior wall, and double infarction) with reduced EF. The modification of the mitral-septal separation measurement according to D'Cruz et al. showed no advantage over that proposed by Massie et al. Both are clearly dependent upon septal excursion, which has to be taken into consideration when mitral-septal separation is being evaluated. The sensitivity of mitral-septal separation (greater than 7 mm) for the detection of reduced LV function (less than 55%) was 0.66; the specificity was 0.80. There was greater sensitivity for anterior wall infarctions than for posterior wall infarctions (0.73 vs 0.44). Because of the relatively high number of false negatives, only a pathologic mitral-septal separation is diagnostically useful.

Adult↗
PubMed1982

[Electrocardiography and quantitative levocardiography in chronic transmural infarct. A correlative study].

For evaluation of a connection between the electrocardiographic diagnosis and localisation of chronic infarction and the angiographic results left ventriculography data of 97 patients with coronary heart disease were assessed quantitatively according to the method of Mathes. According to electrocardiographic criteria of infarction six subgroups were distinguished: anteroseptal, anterior, anterolateral, inferior, inferiolateral, and posterolateral. Asynergies were demonstrable in 87% of patients with infarct electrocardiograms, normal ventricular function was seen in 80% of patients without infarct ECG. Asynergies were seen in 75% of electrocardiographically diagnosed anterior wall infarcts and in 92% of posterior wall infarcts. The sensitivity of the ECG in chronic infarction was 83%, the specificity 84%. Pronounced differences in the number of involved segments were found between inferior and inferiolateral infarction. In contrast, no clear-cut differentiation of electrocardiographic findings judged by segmental involvement in the left ventriculography was seen for the anterior wall. The extent of the anterior wall infarction diagnosed by electrocardiography did not correlate with results of left ventriculography. The ECG is a suitable means for detection of segmental disturbances of contraction also in the chronic infarction stage. However, localisation and extent of the lesion can only be assessed within limits.

Angiocardiography↗
PubMed1982

[Treatment of gonarthrosis].

In an open study in 89 out-patients the effect of superoxide dismutase (Orgotein) in gonarthrosis (n = 75), post-operative or post-traumatic irritation (n = 8) and chondropathy (n = 6) was investigated. Orgotein (4 mg) was give intra-articularly once weekly for several weeks. The overall rating showed efficacy of this new antiphlogistic compound in 81 out of 89 patients (91%). In eight patients the results of treatment were insufficient. In 65 (80%) out of the 81 successfully treated patients no relapse appeared. Six patients reported reappearance of slight complaints so that in 75 out of 81 successfully treated patients, even after repeated controls, a long lasting pain relief could be achieved. Only in three cases the tolerance of Orgotein was not assessed as "very good" ("good" in one case and "moderate" in two cases). The patients reacted--despite good tolerance of the first injections--after the 4th or 5th injections with irritation and swelling as well as effusion; these symptoms were reversible within 24 hours.

Adult↗
PubMed1982

The geniculocortical system in the early postnatal kitten: an electrophysiological investigation.

The transmission of neuronal impulses in the central visual system in kitten 7-42 days old has been investigated using electrophysiologic techniques. It was found that shortly after birth the axonal conduction velocities in the geniculocortical, in the corticogeniculate and in the commissural pathways of areas 17, 18, and 19 are less than 1.2 m/s, increasing up to maximal 10 m/s at the end of the first postnatal month. The monosynaptic delays across geniculocortical and commissural synapses in area 17 as measured during the third and fourth postnatal week are extremely long (between 2.8 and 6.1 ms) and do not change significantly during this time. During the first postnatal month, visual cortical neurons fatigue rapidly to visual and electrical stimulation; also, the proportion of neurons receiving polysynaptic inputs is much smaller than in the adult animal. Accordingly, neurons having complex receptive fields are rarely found in area 17 during the first postnatal month. Our experiments show that the geniculocortical and also the intracortical transmission of neuronal impulses are still immature at the end of the first postnatal month; at this time the systems for orientation and direction selectivity in the visual cortex are almost fully developed.

Animals↗
PubMed1982

[Comparative studies of transplant reaction of differently preserved corneas in perforating keratoplasty of rat eyes].

We examined the healing process of transplanted rat corneas in relation to the swelling of the grafts. Rat corneas were stored parallel in Macrodex 6% (Knoll) and MK medium (McCarey and Kaufman) at 4 degrees C for 48 h and successively applied in penetrating keratoplasty. The healing process was investigated by observation with a slit lamp and histological methods. Graft swelling before transplantation did not influence the healing process. We concluded that decreased graft swelling is not paralleled by improved wound healing in rat corneas. This phenomenon confirms our previous observations of bovine corneas, that decreased water uptake in vitro is not paralleled by increased vitality of the corneas.

Animals↗
PubMed1982

Kearns-Sayre syndrome: primarily a mitochondriopathy?

Histopathological changes of the external eye muscles and of the peripheral skeletal muscles of 2 patients with Kearns-Sayre syndrome are demonstrated histochemically and electron microscopically. In one case the progression of the mitochondrial anomalies in this disease was documented through ultrastructural investigations of muscle biopsies over a period of 17 years. By freeze-fracture the membrane fracture faces of the transformed mitochondrial were examined in both patients. Biochemical results of one patient show that energy production by glycolysis is distinctly decreased with respect to oxydation. Clinical, morphological and biochemical results support the hypothesis that the Kearns-Sayre syndrome is caused by a primary mitochondriopathy which is not limited to the musculature.

Adult↗
PubMed1982

Adrenal insufficiency, myopathic hypotonia, severe psychomotor retardation, failure to thrive, constipation and bladder ectasia in 2 brothers: adrenomyodystrophy.

Two brothers are described who manifested primary adrenal insufficiency, dystrophic myopathy, severe psychomotor retardation, failure to thrive, fatty degeneration of the liver, megalocornea, chronic constipation, and terminal bladder ectasia until their death at 3 8/12 and 1 7/12 years, respectively. The differential diagnosis to similar syndromes is discussed. This combination of problems apparently has not yet been described. The term adrenomyodystrophy is suggested.

Adrenal Insufficiency↗
PubMed1981

Serum levels of myoglobin and creatine kinase in Duchenne muscular dystrophy.

Using a sensitive myoglobin-radioimmunoassay (Mb-RIA) serum Mb was measured in 50 patients with Duchenne muscular dystrophy (DMD) and compared with the serum creatine kinase (CK) activities. The Mb concentrations (normal range 4-60 ng/ml) measured ranged between 160-6,000 ng/ml and did not only show a significant correlation to the CK but also an inverse relationship to the age of the patients. It is suggested that Mb is an essential adjunct in the diagnosis of DMD.

Adolescent↗