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J Knappe

Publications and source records attributed to J Knappe.

At least 37 records · Page 2Linked to original sources

[Results of a 2-year intervention for the modification of atherosclerosis precursors in school children].

801 children aged 10-11 years were examined in 1984, before an allocation in two groups (intervention vs. control). The scope of the intervention was to modify mean values of blood pressure, total cholesterol and smoking through relevant modification of knowledge and behavior. An intermediate assessment, conducted 2 years after the first exam, showed better knowledge regarding cardiovascular diseases and more sport practice in the intervention group, although smoking habits were only slightly modified. Diet, body weight, blood pressure and blood lipid levels did not show any significative differences. The study is now ongoing.

Anthropometry

[Prevention of ischemic heart disease--experiences and conclusions from the Erfurt intervention study].

The concept of the primary prevention of the ischaemic heart disease by modification of the main factors of risk smoking of cigarettes, hypercholesterolaemia and high blood pressure at present got an up to now not achieved degree of probability. Nowadays we no more doubt about the fact that profound changes of nutrition, on optimum treatment of hypertension and a regression of the consumption of cigarettes might have a clear influence on case rates and mortality rates of ischaemic heart disease, but also of other chronic diseases. Also for our country the principal possibility of a preventive influence was confirmed (Erfurt intervention study). The prevention of the ischaemic heart disease by modification of the main factors of risk as an integrated constituent of medical activity by far more than up to now must be introduced into the principal medical care. But in the first place prevention is also a task of the state and the whole society.

Coronary Disease

[Clinical and paraclinical findings on status following prosthetic heart valve replacement with special reference to the behavior of pulmonary pressure].

Retrospectively were evaluated clinical findings of 151 patients with condition after replacement of artificial cardiac valves (Björk-Shiley), who were treated in our department of cardiology in 1986. The patients with mitral valve replacement (MVR) and mitral valve and aortic valve replacement showed the highest rate of individualisation in comparison to aortic valve replacement. 18 patients showed complications and acute deteriorations, respectively, two of which had a fatal course. In 53 patients the bicycle-ergometric exercises were performed with measurement of the pulmonary pressure. Of these patients the majority indeed subjectively improved in their behaviour, however, the objective exercise tolerance was altogether low and the rate of invalidisation increased in comparison to the preoperative rate. The pulmonary pressure at rest in the majority of the patients was reduced mostly in dependence on the initial values. Increases appeared only sporadically. Under exercise, however, particularly the patients with mitral valve replacement showed pathological increases of pressure. Altogether the best results showed patients with aortic valve replacement also with regard to the shrinking of the radiologically established size of the heart.

Adolescent

[Clinical aspects, diagnosis, therapy and course of unstable angina pectoris].

It is reported on 27 patients aged 32-77 years with an unstable angina pectoris, including coronary spasm. All patients showed an anamnesis of less than 3 months, nearly the half of less than 24 hours. The resting electrocardiogram during the attack was pathological in 22 patients, 7 patients showed a Prinzmetal reaction and 11 patients showed intermittent ventricular dysrhythmias. The exercise electrocardiogram in the stable phase was pathological in 16 of 17 patients. Of 23 patients who underwent a selective coronary angiography with laevocardiography 9 patients each showed a disease of one vessel and three vessels, respectively, and 5 patients a disease of two vessels. Only nearly 50% of the patients could be stabilized medicamentously (nitrates, calcium antagonists, rarely beta-blockers). In three patients still during the unstable phase a surgical revascularization was carried out, in 11 patients after stabilization. Five patients suffered an early infarction; one of them died. Altogether, the unstable angina pectoris is even nowadays to be regarded as a clinical picture with a relatively bad prognosis, which demands rapid action.

Adult

Atherosclerosis precursors in schoolchildren--results of a two-year intervention study.

In order to reduce precursors of atherosclerosis, an intervention trial was carried out in pupils aged 10-11 years at the time of inclusion into the study (5th graders). The main goal of the study was to encourage health-promoting behaviour patterns--mostly present in the schoolchildren at that time--such as non-smoking, a negative attitude toward future smoking, a high level of physical activity including sports. The study design included dietary measures aimed at lowering blood pressure and total cholesterol values. Follow-up examination, performed at an interval of 2 years, revealed the following results: significantly lower mean total cholesterol values in girls attending the intervention schools; a significantly lower prevalence of smoking and a decrease in the number of casual smokers--compared with data obtained in the 5th grade--in the intervention schools; a negative attitude towards smoking and the extent of sport activities remained at the level of the 5th grade in the intervention schools.

Arteriosclerosis

[Acute electrophysiological effects of cardiac glycosides on sinus node function and ventricular repolarization under clinical conditions].

The influence of digoxin, digitoxin and g-strophanthin (ouabain) on the sinus node function (recovery time, sinoatrial conduction time, PP-interval) and on ventricular repolarisation (corrected QT interval and QT during permanent atrial stimulation) was studied in 101 patients (36 with sick sinus syndrome-SSS, 34 with ischaemic heart disease-IHD, and 31 control patients without cardiac disease). Digoxin caused marked prolongation of sinoatrial conduction time (in SSS and in control patients), digitoxin prolonged the PP interval (in IHD and SSS patients); digitoxin and ouabain shortened the QTcorr in SSS patients, ouabain shortened also QT during atrial pacing. The results do not point to specific indication of individual glycosides in sinus node function disturbances. Under certain clinical prerequisites, however, digitoxin can be recommended in ventricular ectopic contractions caused by prolonged or inhomogeneous repolarisation, and also the capacity of ouabain to shorten the repolarisation time deserves attention.

Cardiac Pacing, Artificial

[Acute beta blocker poisoning].

It is reported of acute beta-blocker intoxications in 34 patients (16 with talinolol, 18 with propranolol ingestion). The mean ingestion dose was for talinolol 2.5 g, for propranolol 1.55 g, the mean time of latency up to the appearance of intoxication symptoms 116 min after intake of talinolol, 79 min after intake of propranolol. The picture of intoxication was characterized in the two substances by the antiadrenergic effects, there was no more a cardioselectivity in the high ingestion doses. In talinolol were in the first place dysrhythmias, hypotension and vomiting and nausea, respectively, in propranolol central-nervous symptoms and hypotension. Substance-specific intoxication symptoms are also possible. In mixed intoxications alcohol accelerated the beginning of the effect, sedatives prolonged the latency. Threatening of life is to be expected in ingestion doses over 2 g. In 6 patients the course was lethal after extreme doses of talinolol - according to the present experiences due to the too late beginning of therapy and/or insufficient intensity of therapy. Distinct intoxication symptoms need extremely high applications of antidotes of beta-stimulants, in their inffectiveness glucagon. Furthermore, treatment with cardiac pacemakers and 24-hour control in an intensive care unit proved necessary.

Adolescent

Contribution to the pathogenesis of essential hypertension: a multivariate analysis of associated factors.

This study attempts to develop a general aetiological concept of essential hypertension by multidimensional investigation of its various risk factors in childhood and adolescence. The investigation is based on married couples and their children (609 parents and their 639 children, a total of 1248 persons), all of them chosen under special aspects. Familial and environmental characteristics of children and young people with hypertension are compared with those of normotensive volunteers of the same age. The multi-dimensionally interacting factors found to be associated with hypertension in children are: hypertension, diabetes and early infarction in relatives of the first or second degree as well as overweight at birth, obesity, nutritional patterns in the earliest and later stages of life, social environment and physical activity of the children and adolescents. The familial factors most likely lead to a predisposition to hypertension while environmental factors may subsequently contribute to its manifestation.

Adolescent

Pyruvate formate-lyase (inactive form) and pyruvate formate-lyase activating enzyme of Escherichia coli: isolation and structural properties.

The catalytically active form (Ea) of pyruvate formate-lyase in Escherichia coli cells is generated from an inactive form of the enzyme (Ei) through a post-translational process that requires a distinct activating enzyme and is linked to the cleavage of adenosylmethionine to methionine and 5'-deoxyadenosine. Ei and the activating enzyme were purified to homogeneity and structurally characterized. Ei has an alpha 2 oligomeric structure (2 X 85 kDa) and contains no cofactor. The amino acid composition has been determined. Out of a total of six cysteinyl residues per subunit, one shows an unusually fast reaction with iodoacetate (k2 = 7 (M-1 s-1) at pH 6.8, 30 degrees C), which is accompanied by loss of the activatability of the enzyme. The 1500-fold purified activating enzyme is a monomeric protein of 30 kDa. It contains a covalently bound, as yet unidentified chromophoric factor which has an optical absorption peak at 388 nm. Further studies of the in situ state of pyruvate formate-lyase detected a reversible backconversion of the active form Ea into Ei when anaerobic cells become nutrient-depleted.

Acetyltransferases

On sudden death.

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Death, Sudden

Post-translational activation introduces a free radical into pyruvate formate-lyase.

Pyruvate formate-lyase (formate acetyltransferase; EC 2.3.1.54) of Escherichia coli cells is post-translationally interconverted between inactive and active forms. Conversion of the inactive to the active form is catalyzed by an Fe2+-dependent activating enzyme and requires adenosylmethionine and dihydroflavodoxin. This process is shown here to introduce a paramagnetic moiety into the structure of pyruvate formate-lyase. It displays an EPR signal at g = 2 with a doublet splitting of 1.5 mT and could comprise an organic free radical located on an amino acid residue of the polypeptide chain. Hypophosphite was discovered as a specific reagent that destroys both the enzyme radical and the enzyme activity; it becomes covalently bound to the protein. The enzymatic generation of the radical, which is linked to adenosylmethionine cleavage into 5'-deoxyadenosine and methionine, possibly occurs through an Fe-adenosyl complex. These results suggest a radical mechanism for the catalytic cycle of pyruvate formate-lyase.

Acetyltransferases

[Combined use of talinolol and beta adrenergic stimulants in status asthmaticus. Report on 3 patients].

Experiences in combined use of beta-adrenergic stimulants and cardioselective beta-receptor blocker Talinolol are reported in 3 patients in Status Asthmaticus. High dose Aminophyllintreatment in these 3 severe cases was insufficient, in 1 case it had to be finished because of toxic side effects respectively. For adrenergic stimulation in two cases Orciprenalin i.v. was given initially, in one case Terbutalinsulfat i.v. By cardioselective adrenergic blockade with low dose Talinolol it became possible to prevent cardiotoxic side effects in preexisting tachycardia and premature ventricular contractions. This combination treatment was continued successfully with Terbutalin and Talinolol p.o.

Adrenergic beta-Antagonists

[Use of propranolol in essential hypertension--results of a 10-year therapeutic course study].

For the control of the antihypertensive efficacy and the long-term tolerance in 1970 156 stable essential hypertensives of the clinical stages I-III were stablized with propranolol (obsidan). After an observation of the course lasting at first one year 58% (n = 90) proved as propranolol responders, 72 of them could be led monotherapeutically over 10 years (maximum mean dose 157 mg/die). The permanent propranolol therapy caused a persisting decrease of blood pressure in the non-hypertensive region (RR less than 160/95 mm Hg) by systolically on an average--44 mm Hg and diastolically--22 mm Hg with an adequate mean reduction of the heart rate of 19% compared with the basis values. Under conditions of the bicycle ergometer (watt-degree test) a significant decrease of the mean values of heart rate and blood pressure depending on the load as well as the tension-time-index could be established; at the same time the physical work capacity increased on an average by 25 Watt. After an abrupt interruption of the chronic propranolol therapy (partial study in 29 hypertensives) blood pressure and heart rate again increased only relatively retardedly. In 10 cases a remaining normotension was observed during the therapy-free phase. There were no paradoxical reactions or discontinuation phenomena; altogether the number of side-effects was low. As a result of our 10-year study of the administration of propranolol the high value of the beta-receptor blockers as a basis medication is to be emphasized in the therapy of hypertension.

Adolescent

[The effectiveness of a prevention program for cardiovascular diseases].

In 1968 the addresses of all men of the annual courses of birth 1914-1923 of an Erfurt district were registered (n = 2 023). The aim population was according to accident subdivided into an intervention and a control group. The test persons of the intervention group were repeatedly investigated and participated in a preventive programme. Up to the final investigation in 1977 the control group remained absolutely intact. After about 10 years the intervention population had a statistically significantly lower frequency of infarction and a lower proportion of hypertensive values of blood pressure. In the younger five-year age group the total mortality was tendencially lower (not significant!) than in the adequate control group. There are no differences in the mortality from heart and circulatory diseases and in the distribution of other risk factors between intervention and control groups. A positive effect of the preventive programme was to be proved theoretically as well as empirically, though the decrease of the real incidence of infarction which is to be calculated was by far lower than generally was supposed.

Aged

Routes of flavodoxin and ferredoxin reduction in Escherichia coli. CoA-acylating pyruvate: flavodoxin and NADPH: flavodoxin oxidoreductases participating in the activation of pyruvate formate-lyase.

Flavodoxin and ferredoxin become reduced in Escherichia coli cells by oxidoreductase reactions which use pyruvate and NADPH as electron donor substrates. The two enzymes, which are minor proteins of this organism, were measured through the reduced flavodoxin-dependent activation of pyruvate formate-lyase. The NADPH-dependent enzyme, obtained homogeneously through Procion-red affinity chromatography, was identified as the flavoprotein 'component R' described previously by Fujii and Huennekens [J. Biol. Chem. 249, 6745-6753 (1974)]. The pyruvate-dependent enzyme was identified as CoA-acetylating pyruvate:flavodoxin (ferredoxin) oxidoreductase. Its catalytic properties in the forward, reverse, and the 14CO2-pyruvate exchange reaction are reported. The dihydro form of flavodoxin was characterized as the particular species involved in the activation of pyruvate formate-lyase. The activation process still occurs with 70% of maximal efficiency when the ratio [NADPH]/([NADP] + [NADPH]) is fixed at the intracellular 'anabolic reduction charge' value of 0.45, in conjunction with the NADPH-dependent enzyme. The [2Fe-2S] ferredoxin, though being readily used as electron acceptor of both oxidoreductases and having a redox potential similar to flavodoxin, proved incompetent in mediating the activation of pyruvate formate-lyase.

Acetyl Coenzyme A

[Prevention of hypertension of the city borough of Schwedt/Oder--results to date of a regional intervention program].

More than 1,100 women and about 1,400 men, detected as being hypertensives in population screenings for cardiovascular diseases and coronary risk factors on 30-59 year-old females and 30-64-year-old males 1975 and 1976, respectively, in Schwedt - participation rate in both screenings 78 per cent (6,514 females and 7,137 males, respectively) - underwent an intervention programme carried out by all the general practitioners, physicians for industrial medicine and internists, working in the out-patient clinics of the territory. But in 1979 only 500 of these women and approximately 800 of these men were under continuous control. These registration rates after both the screenings as well as after the first follow-up in women 1977, therefore, have to be considered as unsatisfying. That lack in registration is mainly up to the enormous fluctuation of patients - and inhabitants at all-, being a characteristic feature of the population of the newly built town of Schwedt. In order to overcome these effects of migration within the territory and to improve supervision in hypertensives, a new control system regarding the peculiarities of Schwedt was established. In contrary to the failing registration an efficient lowering of blood pressure levels was achieved in those patients cooperating well, revealing normotensive diastolic mean values and systolic mean values, ranging from normotension to the lower borderline pressures. In women who showed a more impressive effect of treatment than men, the effective lowering could be maintained over a 4-year-follow-up period up to now.

Adult