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Biomedical subjects

W Klein

Publications and source records attributed to W Klein.

At least 127 records · Page 7Linked to original sources

[The extent of diastolic dysfunction and its correlation with subjective impairment of physical capacity in dilated cardiomyopathy].

OBJECTIVE: To find out whether in patients with dilated cardiomyopathy (DCM) there is a correlation between subjective reduction in physical capacity and the transmitral Doppler profile as a measure of left ventricular (LV) filling. PATIENTS AND METHODS: 30 consecutive patients (24 men, six women; average age 55 +/- 2 years) with chronic primary DCM were examined by Doppler echocardiography to determine possible differences in LV filling pattern, in correlation with subjective impairment of physical capacity graded according to the New York Heart Association (NYHA) classification. RESULTS: Mean LV ejection fraction was 34 +/- 1%. All patients were in sinus rhythm. Eight patients, in NYHA class I had nearly normal LV filling (E wave 79 m/s, A wave 0.76 m/s); 11 patients in class II had impaired relaxation (E wave 0.77 m/s. A wave 0.82 m/s) and 11 in class III/V had a restricted filling pattern (E wave 0.98 m/s. A wave 0.57 m/s). There was a significant difference between class II and class III/IV patients with regard to E wave deceleration time (0.15 and 0.11 s, respectively; P < 0.05), as well as between class I and class III/IV patients (0.18 and 0.11 s, respectively; P < 0.05). The A wave deceleration time was clearly shorter in class III/IV than class II (0.08 s and 0.11 s; P < 0.05) and class I patients (0.08 s and 0.10 s; P < 0.05). CONCLUSIONS: The extent of LV diastolic dysfunction correlated with subjective physical capacity. The more the LV filling pattern had changed from normal towards restricted, the greater the patient's symptoms.

Cardiomyopathy, Dilated↗

Comparison of low-molecular-weight heparin with unfractionated heparin acutely and with placebo for 6 weeks in the management of unstable coronary artery disease. Fragmin in unstable coronary artery disease study (FRIC)

BACKGROUND: Low-molecular-weight heparin has a number of pharmacological and pharmacokinetic advantages over unfractionated heparin that make it potentially suitable, when used in combination with aspirin, for the treatment of unstable coronary artery disease. METHOD AND RESULTS: Patients with unstable angina or non-Q-wave myocardial infarction (1482) were included in the study, which had two phases. In an open, acute phase (days 1 to 6), patients were assigned either twice-daily weight-adjusted subcutaneous injections of dalteparin (120 i.u./kg) or dose-adjusted intravenous infusion of unfractionated heparin. In the double-blind, prolonged treatment phase (days 6 to 45), patients received subcutaneously either dalteparin (7500 i.u. once daily) or placebo. During the first 6 days, the rate of death, myocardial infarction, or recurrence of angina was 7.6% in the unfractionated heparin-treated patients and 9.3% in the dalteparin-treated patients (relative risk, 1.18; 95% confidence interval [CI], 0.84 to 1.66). The corresponding rates in the two treatment groups for the composite end point of death or myocardial infarction were 3.6% and 3.9%, respectively (relative risk, 1.07; 95% CI, 0.63 to 1.80). Revascularization procedures were undertaken in 5.3% and 4.8% of patients in unfractionated heparin and dalteparin groups, respectively (relative risk, 0.88; 95% CI, 0.57 to 1.35). Between days 6 and 45, the rate of death, myocardial infarction, or recurrence of angina was 12.3% in both the placebo and dalteparin groups (relative risk, 1.01; 95% CI, 0.74 to 1.38). The corresponding rates for death or myocardial infarction were 4.7% and 4.3% (relative risk, 0.92; 95% CI, 0.54 to 1.57). Revascularization procedures were undertaken in 14.2% and 14.3% of patients in the placebo and dalteparin groups, respectively. CONCLUSIONS: Our results add to previous evidence suggesting that the low-molecular-weight heparin dalteparin administered by twice-daily subcutaneous injection may be an alternative to unfractionated heparin in the acute treatment of unstable angina or non-Q-wave myocardial infarction. Prolonged treatment with dalteparin at a lower once-daily dose in our study did not confer any additional benefit over aspirin (75 to 165 mg) alone.

Adult↗

[Beta blockers--1997 update].

Beta blockers have been used as first-line drugs in the treatment of numerous cardiovascular disorders such as hypertension and ischemic heart disease, as well as for certain non-cardiovascular diseases for more than 30 years. However, the administration of these safe and effective drugs declined during the 1980s, whereas the use of others such as calcium antagonists and ACE inhibitors increased for these indications, frequently without convincing evidence of any clinical advantages of these agents in hard end points. During the past two or three years there has been a renaissance of beta adrenoceptor antagonists, most probably due to increasing awareness that beta blockers have been shown to reduce morbidity and mortality when compared with other therapeutic agents or placebo in numerous diseases. Furthermore, congestive heart failure has changed from being a contraindication to an indication, and suspected side effects were not confirmed on further investigation. Last but not least the reasonable costs of beta blocking drugs may have become a more important consideration than before. The trend back to beta blockers may also be due to the fact that physicians attach more importance to effects on the hard end points, namely a decrease in morbidity and mortality, than to surrogate end points. According to the present state of the art, beta blockers should be recognized as the drugs of choice, particularly in the treatment of arterial hypertension and coronary artery disease (especially after myocardial infarction), unless contraindications are present or unacceptable side effects occur. Congestive heart failure, peripheral arterial disease (PAD) and diabetes mellitus are no longer considered absolute contraindications.

Adrenergic beta-Antagonists↗

Comparison of saruplase and alteplase in acute myocardial infarction. SESAM Study Group. The Study in Europe with Saruplase and Alteplase in Myocardial Infarction.

Four hundred seventy-three patients with acute myocardial infarction (AMI) were treated with either saruplase (80 mg/hour, n = 236) or alteplase (100 mg every 3 hours, n = 237). Comedication included heparin and acetylsalicylic acid. Angiography was performed at 45 and 60 minutes after the start of thrombolytic therapy. When flow was insufficient, angiography was repeated at 90 minutes. Coronary angioplasty was then performed if Thrombolysis In Myocardial Infarction (TIMI) trial 0 to 1 flow was seen. Control angiography was at 24 to 40 hours. Baseline characteristics were similar. Angiography showed comparable and remarkably high early patency rates (TIMI 2 or 3 flow) in both treatment groups: at 45 minutes, 74.6% versus 68.9% (p = 0.22); and at 60 minutes 79.9% versus 75.3% (p = 0.26). Patency rates at 90 minutes before additional interventions were also comparable (79.9% and 81.4%). Angiographic reocclusion rates were not significantly different: 1.2% versus 2.4% (p = 0.68). After rescue angioplasty, angiographic reocclusion rates of 22.0% and 15.0% were observed. Safety data were similar for both groups. Thus, (1) early patency rates were high for saruplase and alteplase treatment, (2) reocclusion rates for both drugs were remarkably low, and (3) complication rates were similar. Thus, saruplase seems to be as safe and effective as alteplase.

Aged↗

[Pathophysiological mechanisms of the renin-angiotensin system and its pharmacologic modification by ACE inhibitors or angiotensin II (type 1) receptor blockers in cardiovascular diseases].

As a net effect of ACE-inhibitors and AT1-receptor antagonists on the renin-angiotensin system (RAS) cardioprotection due to vasodilative (reduction of blood pressure, afterload reduction), antiproliferative (reduced cell growth, reduction of "vascular" and/or "ventricular remodeling", reduced formation of extracellular matrix), as well as antiadrenergic actions and due to the stimulating effect on natriuresis, reduction of blood pressure, preload reduction can be expected. These aims of therapy have mostly been confirmed for the action of ACE-inhibitors by experimental and clinical studies but except for the treatment of arterial hypertension and few preliminary reports concerning the treatment of cardiac dysfunction, no comparable data are available for AT1-receptor antagonists. To date, an antithrombotic and profibrinolytic action could only be demonstrated for ACE-inhibitors. This effect has been discussed to be responsible for the improvement of long-term prognosis in patients with coronary artery disease. Despite the similar spectrum of action there exist important differences between ACE-inhibitors and AT1-receptor antagonists that might underline the need of an individual use of these drugs: the dual action of ACE-inhibitors on the RAS and the kinin system bears many benefits but has been also shown to be accompanied by side-effects, mainly chronic dry cough, in a relatively high percentage of patients thus leading to discontinuation of therapy in 8-14%. This respective side-effect can be prevented by the use of AT1-receptor antagonists. It has been discussed whether the incomplete action of ACE-inhibitors on AT1-receptor-mediated effects is at least in part responsible for the efficacy of this drug which is relatively high (75-80%) as compared to other substances. Due to their direct action, AT1-receptor-blockers might also be of high effectiveness for the treatment of severe heart failure. A combination of the ACE-inhibitor-mediated activation of the kinin-system with the more specific blockade of AT1-receptors by AT1-receptor antagonists might be of benefit and is currently under investigation. Finally, it has been discussed that the increased AT II concentration in case of AT1-receptor-blockade activates AT2-receptor-mediated mechanisms thus leading to an additive vasoprotective effect.

Angiotensin Receptor Antagonists↗

Assessment of the environmental behaviour of antioxidants in folios. Comparative risk analysis for the use of folios in agriculture.

The objective of the reported study has been to assess and evaluate as comprehensively as possible the environmental impact of Octadecyl 3(3,5-di-tert-butyl-4-hydroxyphenyl) propionate (CAS no: 2082-79-3, Irganox 1076, Ciba Specialty Chemicals Inc., Additives), which is used as an antioxidant. The potential impact on the compartments soil, groundwater and surface water is to be considered. For comparative purposes, additionally, other chemical compounds being currently under environmental discussion are also taken into account. These comprise pesticides and phthalates which are ubiquitously distributed plasticizers as well as a complexing agent. Since the data basis for each of the compounds under consideration is different, a tiered approach comprising various methodologies of impact assessment has been chosen to achieve the best possible comprehensiveness. The tiers are: 1. Tier: hazard assessment using a scoring system 2. Tier: comparative risk assessment. When interpreting the results of each method, system boundaries as well as underlying assumptions were taken into consideration. Both methodologies showed, that-as compared to the reference substances-there is no relevant environmental and toxicological concern due to low environmental and human hazard from Octadecyl 3(3,5-di-tert-butyl-4-hydroxyphenyl) propionate.

Agriculture↗

Increased neopterin in patients with chronic and acute coronary syndromes.

OBJECTIVES: The aim of our study was to determine neopterin levels in patients with chronic and acute coronary syndromes. BACKGROUND: In chronic and acute coronary syndromes the release of different cytokines activates cellular defense. Infiltration of neutrophils and monocytes/macrophages is detected in the vessel wall as well as in the myocardium. Neopterin, which is a by-product of the guanosine triphosphate-biopterin pathway, is a marker for those activated macrophages. METHODS: We studied 123 subjects: 1) 21 consecutive patients (17 men, 4 women; mean age +/- SD 66 +/- 15 years, range 31 to 87) with acute myocardial infarction (AMI); 2) 62 consecutive patients (50 men, 12 women; mean age 61 +/- 8 years, range 43 to 81) with signs and symptoms of clinically stable coronary artery disease (CAD); and 3) 40 healthy blood donors (28 men, 12 women; mean age 35 +/- 13 years). Neopterin levels were determined with a commercially available enzyme-linked immunosorbent assay method. RESULTS: In patients with AMI before thrombolytic therapy, neopterin levels were significantly higher than levels in patients with CAD and control subjects (13.7 vs. 8.6 and vs. 6.8 nmol/liter, p < 0.0001). Values also differed significantly between patients with CAD and control subjects (p < 0.0001). Neopterin levels in patients with AMI were measured seven times during a 72-h period. Within-group comparison showed significant differences over this period (p < 0.00001). The lowest value (11.4 nmol/liter) was observed after 4 h and differed significantly from the initial value and values after 24 and 72 h (p < 0.05). After 72 h, neopterin increased to 14.9 nmol/liter, a value significantly different from all values other than the initial one. There was no correlation between neopterin and creatine kinase (CK); CK, MB isoenzyme; or lactate dehydrogenase as markers for the extent of the myocardial infarction during the observation period. CONCLUSIONS: Our data support the hypothesis of an activation of monocytes and macrophages in patients with an acute or chronic coronary syndrome. Neopterin as a marker for macrophage activation is significantly increased in patients with chronic CAD and more pronounced in patients with AMI shortly after the onset of symptoms.

Adult↗

Bradydysrhythmia-related presyncope secondary to pheochromocytoma.

Pheochromocytoma endures as a life-threatening disorder. In the absence of systemic hypertension, diagnosis may be difficult. We present a 46-year-old normotensive male with a history of presyncope. One of these episodes could be documented, and revealed symptomatic bradycardia suspicious of sinus node arrest. Due to hints of an elevated sympathetic tone (Schellong test, circadian blood pressure pattern without diurnal rhythm) 24-h urinary catecholamine concentrations were measured and found increased. MIBG-scintigraphy and abdominal-computed tomography indicated the location of the pheochromocytoma. After removal of the tumour, no further episodes of presyncopes or bradydysrhythmias were observed.

Adrenal Gland Neoplasms↗

Left ventricular function in response to the transition from aerobic to anaerobic metabolism.

The purpose of this investigation was to study myocardial function at rest, during three phases of energy supply, and during recovery. Radionuclide angiography was performed during the aerobic phase (phase I, rest-first lactate increase), the aerobic-anaerobic transition phase (phase II, first lactate increase-second lactate increase), the anaerobic phase (phase III, second lactate increase-maximal work performance (Pmax)), and during recovery. Thirty-eight male patients (59 +/- 7 d after myocardial infarction) were compared with 19 healthy control subjects and 21 sport students of comparable age. Left ventricular ejection fraction (LVEF) increased from rest to phase I and from phase I to phase II in sports students and control subjects. During phase III, LVEF did not change significantly in sports students, but it decreased significantly in control subjects. This is in contrast to the patients, who showed an increase of LVEF from resting values (47 +/- 3%) to phase I (50 +/- 1%), no change during phase II (51 +/- 2%), and a decrease to resting values (45 +/- 2) during phase III. All subjects showed an increase in stroke volume (SV) during phase I and II, reaching a maximum at phase II. This was evidenced by an improvement of the systolic function with a constant left ventricular end-diastolic volume (EDV) in control subjects and sports students. In contrast, an improved SV in patients was achieved through an increase in EDV and a less distinct increase in the left ventricular end-systolic volume (ESV). Maximal LVEF values were measured during the first 90 s of recovery in all subjects. Values during recovery are not representative of load dependent myocardial function. This increase in LVEF does not cause an increase in cardiac output but is a consequence of changes in the EDV and ESV, which decrease again immediately after the end of exercise performance.

Adult↗

[Angiosarcoma of the hand. Case report].

Angiosarcoma is a very rare malignant bone tumour. The case of a 45-year-old man is presented with a primary epithelioid hemangioendothelioma in the fourth metacarpus. After radical extirpation of the tumour radiation followed. The function of the hand was fully preserved. Five years after operation the patient is free of disease.

Bone Neoplasms↗

[Chemical-physical risks originating from dead animals or animal products for the health of humans and animals and for the environment].

On-farm burial of dead stock principally may lead to an exclusively local contamination of groundwater by nitrogen species and dissolved organic matter. This definitively is a local risk, the size of which, however, depends on the amounts of dead animals buried and the hydrogeological conditions of the site. Emission mitigation by rendering companies has resulted in emissions, which do not present a hazard to humans, animals and the environment. The valuable recycling products contain ubiquitous pollutants in minor concentration not resulting in a effective relevant risk. The role which recycling in rendering plays, as regards redispersion of pollutants and active ingredients, also is very low for the chemicals which have been assessed so far. The role of veterinary medicinal drugs, however, especially of antibiotics for the risk in the environment needs attention.

Animal Husbandry↗