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E Dingeldein

Publications and source records attributed to E Dingeldein.

18 recordsLinked to original sources
PubMed1991

The release of gentamicin after total hip replacement using low or high viscosity bone cement. A prospective, randomized study.

Low viscosity bone cement is expected to give improved long term fixation of prosthetic components by increased intrusion into cancellous bone. Fixation is more difficult to achieve after revision for infection because of the inferior quality of the bone. We have compared the amount of gentamicin released from high viscosity and low viscosity bone cements in 41 patients undergoing total hip replacement. The concentration of gentamicin in serum and the wound secretion, and the amount recovered from the urine, was about three times higher for low viscosity cement. A possible explanation for this is an increase in surface area of the cement body because of improved intrusion of cement into bone. The improved mechanical fixation and the high concentration of gentamicin of the bone cement interface favours the use of low viscosity cement, especially in revision for deep infection.

Aged↗
PubMed1989

Reaction of the bone structure to methotrexate-Palacos flow y. Experimental investigations in animals.

With the combined osteosynthesis of pathological fractures in association with tumors and/or metastases in mind, E. Merck (Darmstadt, FRG) developed a bone cement containing a cytostatic agent, methotrexate-Palacos flow y (MTX-Pf). The animal-experimental study presented here investigates the tolerability of MTX-Pf in the femurs of rabbits with lateral comparison. In these investigations we used both the concentration of 0.63% MTX, as is currently used in standard clinical surgery, as well as a much higher concentration of 2.5% MTX. The histological sections were investigated using microradiographic methods and provided no indication of any significant differences between the femora with the MTX-Pf implantation and those into which standard Palacos flow y had been implanted.

Animals↗
PubMed1987

[Bone cement containing cytostatic drugs: new aspects in the treatment of malignant bone tumors. I. Experimental studies].

Radical surgery in malignant bone tumors can either be limited by anatomical structures or seems inadequate in the palliative stabilization of bone metastases. Incomplete removal of the tumor and stabilization by compound osteosynthesis or endoprosthesis contains two problems: 1) the wide spread of malignant cells by manipulation in the tumor bearing area; 2) progressive destruction of bone due to remaining tumor. To overcome these problems we developed methotrexate bone cement (MTX-Palacos) with the aim to obtain high local concentrations of methotrexate in order to destroy remaining tumor cells and avoid systemic side effects. In vitro studies showed that methotrexate is released continuously from this cement without relevant changes of its biomechanical properties. Animal studies with transplanted osteosarcomas and mamma carcinomas in mice showed a considerable decrease of tumor growth when a plug of MTX-Palacos was inserted in the center of the tumor. Histological findings showed that in the surroundings of the plug the tumor was destroyed considerably contrary to normal bone cement which had no effect on the tumor at all. The results are discussed with regard to clinical application of MTX-Palacos.

Animals↗
PubMed1987

The intraneoplastic chemotherapy in a rat brain tumour model utilizing methotrexate-polymethylmethacrylate-pellets.

In an experimental glioma model, using ethylnitrosourea induced and subsequently intracerebrally implanted tumours in BD-IX rats, the effectiveness of intratumoural application of methotrexate (MTX) by stereotactic implantation of polymethylmethacrylate (PMMA) pellets containing MTX, has been studied. Tumour volume 10 days after pellet implantation as well as survival rates of treated, untreated and control animals have been the criteria of the effect of treatment. Tumour volume was significantly smaller in treated compared to untreated animals. The survival rate of untreated to treated animals increased 150 and 233% respectively when compared with the control animals. Thus a positive therapeutic effect of MTX-PMMA pellet implantation in the experimental glioma could be proven. Possible consequences for the treatment of human gliomas are shortly discussed.

Animals↗
PubMed1979

Bactericidal activity of cefazedone.

Distinct bactericidal activity of (6R,7R)-7-(2-[3,5-dichloro-4-oxo-1(4H)-pyridyl]-acetamido)-3-([(5-methyl-1,3,4-thiadiazol-2-yl)-thio]methyl)-8-oxo-5-thia-1-aza-bicyclo[4,2,0]oct-2-ene-2-carboxylic acid (cefazedone, Refosporen) could be demonstrated in 2 Staphylococcus aureus and 3 Escherichia coli strains. The effect was less in 1 strain of Proteus mirabilis. Whereas the activity in serum and bile was higher than in nutrient broth, the bactericidal activity in urine was less pronounced. The combination of cefazedone and gentamicin proved to be bactericidal in low concentrations.

Bacteria↗
PubMed1979

[Experimental and pharmacokinetic studies with gentamicin PMMA beads (author's transl)].

Gentamicin PMMA beads (PMMA = polymethylmethacrylate) represent a new form of local antibiotic therapy for treating chronic bone and soft tissue infections. Gentamicin is released in high concentrations from PMMA. The therapeutic efficacy of the beads was demonstrated in a model of bone infection in dogs. Sufficiently high tissue concentrations of gentamicin were measurable for a period of 4 months. A very good tolerance of the beads was demonstrated in dogs as well as in cell cultures. High gentamicin concentrations exceeding the MBC values of relevant pathogens were measurable in patients at the site of infection. Serum and urine concentrations were low and therefore toxic side effects are excluded.

Animals↗
PubMed1979

MIC determination, disc sensitivity testing, and analysis of regression in cefazedone and cefazolin.

Minimum inhibitory concentrations (MIC) of (6R,7R)-7-(2-[3,5-dichloro-4-oxo-1(4H)-pyridyl-a1-acetamido)-3-([(5-methyl-1,3,4-thiadiazol-2-yl)-thio]methyl)-8-oxo-5-thia-1-azabicyclo[4,2,0]oct-2-ene-2-carboxylic acid (cefazedone, Refosporen)), a new semisynthetic cephalosporin derivative were determined by a broth dilution technique. In comparison with cefazolin 130 gram-positive and gram-negative bacteria, recent clinical isolates, were tested. In parallel, inhibition zones for the same organisms were determined by a standardized disc technique using 30-micrograms discs. According to the calculated regression lines a good correlation was found for cefazedone and cefazolin between the MIC values and the diameters of the inhibition zones (correlation coefficients r = --0.90 and --0.92, respectively). Taking into account the dosages recommended for cefazedone and the mean serum concentrations to which they give rise, appropriate categories of sensitivity (break points) for susceptibility testing are recommended.

Bacteria↗
PubMed1979

Blood levels and tissue concentrations of cefazedone in animals.

In mice, dogs, and rabbits blood and serum levels were evaluated after parenteral application of (6R,7R)-7-(2-[3,5-dichloro-4-oxo-1(4H)-pyridyl]acetamido)-3-([(5-methyl-1,3,4-thiadiazol-2-yl)-thio]methyl)-8-oxo-5-thia-1-aza-bicyclo[4,2,0]oct-2-ene-2-carboxylic acid (cefazedone, Refosporen), cephalothin and cefazolin. In all three animal species cefazedone produced higher and more prolonged serum levels than did cefazolin. Evaluation of serum protein binding in mouse, dog and rabbit serum revealed marked differences between the species. Cefazedone and cefazolin tissue concentrations were evaluated in rabbits. Both antibiotics did not penetrate the CSF or brain tissue. In all other tissues examined (except bone marrow) higher and more prolonged tissue levels were attained with cefazedone than with cefazolin.

Animals↗
PubMed1979

Clinical pharmacology phase I of cefazedone, a new cephalosporin, in healthy volunteers. II. Pharmacokinetics in comparison with cefazolin.

In two consecutive cross-over studies, each involving 10 healthy volunteers, the pharmacokinetics of (6R,7R)-7-(2-[3,5-dichloro-4-oxo-1(4H)-pyridyl]-acetamindo)-3-([(5-methyl-1,3,4-thiadiazol-2-yl)-thio]methyl)-8-oxo-5-thia-1-azabicyclo[4,2,0]oct-2-ene-2-carboxylic acid (cefazedone, Refosporen) in comparison with cefazolin were investigated after single i.v. and i.m. administration. The doses were: i.v. cefazedone 500 mg and 1000 mg; cefazolin 1000 mg; i.m. cefazedone 500 mg, cefazolin 500 mg. The pharmacokinetic parameters were analysed by applying an open two-compartment model. The pharmacokinetics of cefazedone are nearly identical with those of cefazolin. In particular, it must be noted that cefazedone has a relatively long serum elimination half-life (1.64 +/- 0.23 h after i.v. and 1.85 +/- 0.51 h after i.m. administration) and that cefazedone exhibits, in comparison with cefazolin, a more favourable concentration ratio of central vs. peripheral (= tissue) compartment (1:2).

Adult↗
PubMed1978

The release of gentamicin from polymethylmethacrylate beads. An experimental and pharmacokinetic study.

Gentamicin incorporated in beads of polymethylmethacrylate has been shown capable of being released over a period of several months in concentrations sufficiently high to control most pathogens. The therapeutic efficacy of such beads has been demonstrated in a model of osteomyelitis of the femur in the dog. Good tolerance has been shown, both in the animal model and in tissue cultures. In forty-one patients with infection of either bone or soft tissue, mainly of the lower limb, the findings were similar. The concentrations in serum and urine were low, which excludes side-effects. The insertion of gentamicin-PMMA beads may prove to be a valuable new form of local antibiotic therapy.

Animals↗
PubMed1978

[The results of experimental and clinical use of Gentamycin PMMA balls (author's transl)].

Authors describe a new method of treatment for bone and soft tissue infections using polymethyl methacrylate balls containing Gentamycin. Advantages of this method can be summarized in 3 points: 1. From the patients point of view saving the rinsing-sucking drainage, early mobilisation etc. 2. From nursing point of view a significant facilitation of the patient's care. 3. From the hospital management's point of view: improved hygienic conditions by eliminating the possible infections related to a rinsing-sucking wet system. Cutting down hospital expences both by abbreviation of the time of hospitalization and saving on expensive antibiotics.

Administration, Topical↗
PubMed1976

[Does methylmethacrylate induce cardiovascular complications during alloarthroplastic surgery of the hip joint? (AUTHOR'S TRANSL)].

Cardiovascular experiments in dogs and rabbits under various conditions demonstrated that monomethylacrylate has no direct cardiac depressant activity. The transient decrease in blood pressure and heart rate of patients receiving endoprostheses and experimental animals is elicited by a vagotropic effect of the methacrylates and can be antagonized by prophylactic application of atropine. Severe cardiovascular incidents involving an acute cor pulmonale are induced via the steep rise in pressure within the bone-marrow canal during the forcing in of the endoprosthetic shafts, leading to intravasation of bone marrow and its thromboplastine like compounds, thus resulting in a partial coagulation. A schedule of simple prophylactic procedures proved to be effective in preventing fatal cardiovascular complications.

Animals↗