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Biomedical subjects

H Radtke

Publications and source records attributed to H Radtke.

At least 19 recordsLinked to original sources
PubMed2001

Validation of the sterilization procedure of allogeneic avital bone transplants using peracetic acid-ethanol.

Different procedures are available to inactivate bacteria and fungi, including their spores, as well as viruses in human bone transplants. The most efficient methods are considered to be gamma irradiation and thermal inactivation as well as chemical sterilization methods like the peracetic acid-ethanol treatment (PES). Following national and international standards or draft standards, the antimicrobial effectiveness of this procedure was evaluated. Due to the standardizable size as well as the clinical relevance, defatted human spongiosa cuboids (15x15x15 mm) served as model system. After treatment with PES for 2 and 4 hours, respectively, the titre of living micro-organisms was determined in the supernatant and the cuboid. A reduction in the titre of viable micro-organisms below the detection level (reduction factor >5 log10) was already achieved after an incubation time of 2 hours (Staphylococcus aureus, Enterococcus faecium, Pseudomonas aeruginosa, Bacillus subtilis, Clostridium sporogenes, Mycobacterium terrae, Candida albicans as well as spores of Bacillus subtilis). No viable micro-organisms could be detected in any of the PES-treated test cuboids. Spores of Aspergillus niger were also completely inactivated. The PES procedure proved to be a reliable method for the sterilization of human bone transplants derived from spongiosa.

Bacteria↗
PubMed2001

Cardiac death after autologous stem cell transplantation (ASCT) for treatment of systemic sclerosis (SSc): no evidence for cyclophosphamide-induced cardiomyopathy.

In patients with systemic sclerosis (SSc) treatment-related mortality after autologous stem cell transplantation (ASCT) appears to be increased as compared to patients with hematological malignancies. In our phase I/II study on ASCT in autoimmune diseases a patient with SSc died on day 2 after ASCT. Here we report the results of the autopsy which revealed advanced pulmonary and cardiac fibrosis as the most probable cause of death. In spite of detailed technical examination before enrollment, the cardiopulmonary function tests did not reflect the advanced stage of the disease. We conclude that in selected patients with SSc, biopsies should be performed to reduce mortality after ASCT.

Cardiomyopathies↗
PubMed2001

Release of WBC-derived IL-1 receptor antagonist into supernatants of RBCs: influence of storage time and filtration.

BACKGROUND: Transfusion-associated immunodepression may be related to the transfer of immunoinhibitory cytokines with blood components. STUDY DESIGN AND METHODS: After evidence of increasing concentrations of IL-1 receptor antagonist (IL-1RA) but not of IL-10 was obtained in supernatants of stored RBC units that were WBC-reduced by centrifugation (C-RBCs) in a pilot study, IL-1RA concentrations were determined weekly in supernatants of C-RBCs and in units that underwent prestorage WBC reduction by in-line filtration (F-RBCs) over a 49-day storage. For assessing total IL-1RA content, complete cell lysis by repeated freezing and thawing was done. The results were related to the changes in WBC count during storage. The dependency of IL-1RA content on preparation procedures was assessed. RESULTS: The prestorage IL-1RA concentration in C-RBCs (859 +/- 218 pg/mL) was significantly higher than in F-RBC (75 +/- 13 pg/mL). Whereas no changes were seen in F-RBCs during storage, IL-1RA levels in C-RBC supernatants drastically increased to levels about 50 times those in normal plasma (16,327 +/- 2,686 pg/mL on Day 49). Follow-up analysis revealed stringent correlation between IL-1RA release into supernatants and the current loss of WBCs (r = 0.79, n = 42; p<0.001). The total IL-1RA content did not change during storage and was directly dependent on prestorage WBC count. Preparation procedures altered the IL-1RA content only by WBC reduction. CONCLUSION: The immunosuppressive cytokine IL-1RA is transmitted by RBCs in relation to WBC content and storage time.

Blood Preservation↗
PubMed2001

Effects of an onion-olive oil maceration product containing essential ingredients of the Mediterranean diet on blood pressure and blood fluidity.

Twenty-four patients with arterial hypertension (WHO class I) received either 4 capsules of an onion-olive oil maceration product, containing essential ingredients of the Mediterranean diet, or placebo daily over a period of one week. In order to investigate the acute effect on arterial blood pressure, measurements were performed before and 5 h after the administration of the first dose of 4 capsules verum or placebo, respectively. For the evaluation of the long term effect further blood pressure measurements were performed after one week's treatment with a daily dose of 4 capsules. After a wash-out phase of 2 weeks followed by a crossover, the second study phase, which was identical in design, was carried out. In addition patients were instructed to measure their blood pressure 4 times daily at home for the whole study period. Haemorheological parameters (platelet aggregation, erythrocyte aggregation, plasma viscosity and haematocrit) were also determined at the measuring points mentioned above. The onion-olive oil maceration product led to a significant decrease in systolic blood pressure. There was also a trend towards a decrease in diastolic blood pressure. The improved blood fluidity observed resulted from a decrease in haematocrit. All effects could be shown immediately and after one week's administration.

Adult↗
PubMed2000

Autologous stem-cell transplantation in refractory autoimmune diseases after in vivo immunoablation and ex vivo depletion of mononuclear cells.

Autoimmune diseases that are resistant to conventional treatment cause severe morbidity and even mortality. In the present study we demonstrate that complete remissions can be achieved in refractory polychondritis and systemic lupus erythematosus (SLE), even at advanced stage, with the use of autologous stem-cell transplantation (SCT). Remissions persisted after reconstitution of the immune system. In the treatment of advanced systemic sclerosis (SSc), stable disease may be achieved with autologous SCT.

Adult↗
PubMed2000

Influence of the onion as an essential ingredient of the Mediterranean diet on arterial blood pressure and blood fluidity.

Mediterranean diet has got a favourable effect on life expectancy. One of the crucial components of the diet are onions. In an open and a randomized, placebo-controlled, double-blind, cross-over phase-I study a spontaneous pharmacological effect 5 h after administration of an onion-olive-oil maceration capsule formulation on arterial blood pressure could be demonstrated in apparently healthy subjects. In addition to a decrease in arterial blood pressure, a significant reduction in plasma viscosity and haematocrit were observed. These results are indicating a vasodilative effect of the onion-olive-oil-maceration product. The stickiness of the platelets was reduced. The effects were stronger in subjects with reduced blood fluidity compared to those subjects with normal rheological parameters.

Adolescent↗
PubMed1999

The antiatherosclerotic effect of Allium sativum.

In a randomized, double-blind, placebo-controlled clinical trial, the plaque volumes in both carotid and femoral arteries of 152 probationers were determined by B-mode ultrasound. Continuous intake of high-dose garlic powder dragees reduced significantly the increase in arteriosclerotic plaque volume by 5-18% or even effected a slight regression within the observational period of 48 months. Also the age-dependent representation of the plaque volume shows an increase between 50 and 80 years that is diminished under garlic treatment by 6-13% related to 4 years. It seems even more important that with garlic application the plaque volume in the whole collective remained practically constant within the age-span of 50-80 years. These results substantiated that not only a preventive but possibly also a curative role in arteriosclerosis therapy (plaque regression) may be ascribed to garlic remedies.

Adult↗
PubMed1999

Rapid reversal of nephrotic syndrome due to primary systemic AL amyloidosis after VAD and subsequent high-dose chemotherapy with autologous stem cell support.

In a patient with nephrotic syndrome, renal biopsy revealed AL amyloid deposits. Monoclonal lambda light chains were identified in serum and urine. A low percentage of monoclonal plasma cells was detected in the bone marrow. The patient received four cycles of VAD and subsequent high-dose chemotherapy (HDCT) with melphalan (200 mg/m2) followed by autologous peripheral blood stem cell transplantation. Proteinuria rapidly diminished during chemotherapy. Three months after HDCT, the patient has no edema, and no signs of plasma cell dyscrasia are currently detectable. Using VAD before starting HDCT may improve the condition of patients with amyloidosis and reduce transplantation-related morbidity and mortality.

Amyloidosis↗
PubMed1995

Plateletpheresis-induced increase in platelet reactivity using different cell separators.

OBJECTIVE: Since plateletpheresis is being used increasingly, it is important to regard quality control to check health risks for donors and to exclude these. DESIGN: Controlled randomised prospective open comparative study. SETTING: Department of Transfusion Medicine of a University Clinic. PARTICIPANTS: 112 platelet donors were examined. INTERVENTIONS: Prior to and after plateletpheresis platelet reactivity was determined. The platelet concentrates in the two groups of 56 donors each were produced using either the cell separator 'CS-3000' and the collecting chamber PLT 30TM with the Omnix system (group I) or the cell separator 'AS-104' (group II). RESULTS: In group I five donors showed a pathologically increased platelet reactivity (p = 0.1297) after plateletpheresis. In group II there were 10 donors with a pathologically increased platelet reactivity (p = 0.0046) after plateletpheresis. The mean concentration of platelets was reduced by separation using the CS-3000 Omnix from 238 +/- 49 x 10(3)/microliters to 172 +/- 32 x 10(3)/microliters (68 +/- 27 x 10(3)/microliters) and from 243 +/- 53 x 10(3)/microliters to 180 +/- 31 x 10(3)/microliters (63 +/- 33 x 10(3)/microliters) using the AS-104. In the first case the platelet yield was 3.9 x 10(11) platelets/concentrate, in the latter case it was 2.9 x 10(11) platelets/concentrate. The 'CS-3000 Omnix' is significantly more effective in separating (58.4 +/- 15.5%) than the 'AS-104' with 44.2 +/- 7.2% (p < 0.0001). CONCLUSIONS: Since both donor groups were comparable regarding all factors recorded--especially the cardiovascular risk factors--the separation process could be responsible for the different traumatisation of platelets.

Adult↗
PubMed1995

[The legally required guidelines for reporting risks or side-effects caused by blood components].

OBJECTIVE: To prevent dangers to health resulting from the application of drugs, the legislator requires the central registration and evaluation of all drug risks, especially of side effects and reciprocal effects. Since 1988 pharmaceutical enterprises have had to denominate a qualified person ('Stufenplanbeauftragter') who is responsible for the fulfilment of obligatory reporting. In case of complaints or side effects he has to take suitable measures according to a special plan ('Stufenplan'). DATA SOURCES: The basis of this survey are the legal requirements for drugs ('Arzneimittelgesetz') and supplementary regulations which define the duties of the 'Stufenplanbeauftragter'. RESULTS: Blood components are subject to the legal requirements ('Arzneimittelgesetz') without reservations. Therefore the corresponding regulations have to be applied without modification in institutes for transfusion medicine. In this article the tasks of the 'Stufenplanbeauftragter' are summarized and practical experience of a university institute for transfusion medicine is presented. CONCLUSIONS: In connection with the transmission of viral infectious diseases it became evident that the 'Stufenplanbeauftragter' is very important for the initiation of effective measures in case of serious side effects. The security of blood components could be improved by the realization of the corresponding legal requirements in the institutes for transfusion medicine.

Adverse Drug Reaction Reporting Systems↗
PubMed1992

The BFM-protocol for HIV-negative Burkitt's lymphomas and L3 ALL in adult patients: a high chance for cure.

During a period of 9 years we used the pediatric BFM-NHL protocol for treatment of 14 adult patients with Burkitt's lymphoma or L3 acute lymphoblastic leukemia. Ten of 14 patients obtained a complete remission including 5/8 with stage-IV disease or B-ALL. After a median follow-up of 55 months none of these ten patients relapsed. The projected survival after 8 years is 71%. Toxicity was moderate, with one early death; a tumor lysis syndrome occurred in four patients. From our experience we conclude that the BFM-NHL protocol is very effective in adult patients, with a high cure rate and acceptable toxicity, even in advanced stages of disease.

Adolescent↗
PubMed1989

Overview of clinical trials with urapidil.

Urapidil has been approved as sustained-release capsules containing 30, 60 and 90 mg, respectively, and as ampules containing 25 and 50 mg for treatment of all grades of hypertension, in several countries in Europe, South America, as well as in Japan and other Asian regions. In general, the treatment should start with 60 mg twice daily, 1 capsule in the morning and 1 in the evening. This schedule may be adapted according to the therapeutic needs. During the last few years, urapidil has been investigated extensively in comparison with several types of established antihypertensive drugs. Urapidil given orally has been tested in comparative trials against placebo, acebutolol, metoprolol, captopril, nifedipine and nitrendipine with responder rates of 40 to 70%. These responder rates are to be expected for a variety of antihypertensive drugs in monotherapy. Further studies with clonidine, prazosin and alpha-methyldopa showed similar responder rates as established for the other antihypertensive drugs studied. Adverse reactions include dizziness, headache and nausea and occasionally tiredness, orthostatic dysregulation and gastric disorders. These symptoms were transient, mostly occurring during the early phases of therapy and disappearing as treatment continued. Adverse effects are considered to be mainly due to blood pressure reduction. Intravenous comparative trials have been performed with urapidil against placebo, diazoxide and sodium nitroprusside. Adverse effects of parenterally applied urapidil are similar to those observed during oral treatment. Specific contraindications for urapidil are unknown. However, as for other vasodilating drugs, intravenous urapidil should not be administered to patients with stenosis of the aortic isthmus or with aortic valve insufficiency.

Administration, Oral↗