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Biomedical subjects

R Wronski

Publications and source records attributed to R Wronski.

17 recordsLinked to original sources
PubMed2005

Neuroprotection of cerebrolysin in tissue culture models of brain ischemia: post lesion application indicates a wide therapeutic window.

All attempts to reduce neuronal damage after acute brain ischemia by the use of neuroprotective compounds have failed to prove efficacy in clinical trials so far. One of the main reasons might be the relatively narrow time window for intervention. In this study 2 different tissue culture models of ischemia, excitotoxic lesion by the use of glutamate and oxygen-glucose deprivation (OGD), were used to investigate the effects of delayed application of Cerebrolysin (Cere) on neuronal survival. This drug consists of low molecular weight peptides with neuroprotective and neurotrophic properties similar to naturally occurring growth factors. After both types of lesion, acute as well as delayed treatment with Cere resulted in a dose dependent and significant rescue of neurons. In the model of excitotoxic cell death significant drug effects were found even when the treatment started with a delay of 96 hours after addition of glutamate. In the OGD model pronounced effects were found after 48 hours delay of treatment, and even after 72 hours a small but significant rescue of neurons was detected. The neuroprotective effects of a single addition of Cerebrolysin to the culture medium resulted in significant protection until end of the experiments which was up to 2 weeks after the initial lesion. A shift of the efficacious dosages from low to high concentrations indicates that most likely active compounds are used up, indicating that multiple dosing might even increase the effect size. In conclusion the results indicate that Cere displays a relatively wide therapeutic time window which might be explained by a combination of acute neuroprotective properties and neurotrophic efficacy.

Amino Acids↗
PubMed2005

[The lethal ingestion of cigarettes in adults: does it really exist?].

HISTORY AND ADMISSION FINDINGS: A 35-year old patient suffering from a borderline personality disorder was admitted to our clinic with ingestions of cigarettes seven times within 15 months. The patient showed symptoms of a nicotine intoxication with agitation, hypertension, tachycardia, dizziness and nausea after ingestion of 7 up to 20 cigarettes. DIAGNOSIS: Mild nicotine intoxication. TREATMENT AND COURSE: After therapy with gastric lavages, activated charcoals and saline cathartics forced acid diuresis were performed in all seven cases of intoxication. All courses were without complications and unit every time the patient could be transferred to the psychiatry within 24 hours after the hospitalization in our clinic. CONCLUSION: An ingestion of more than 6 cigarettes is considered a life-threatening intoxication for adult persons. In spite of the ingestion of 7 up to 20 cigarettes our patient never showed any symptoms of a severe or life-threatening nicotine intoxication. In the last decades no lethal nicotine intoxication after ingestion of cigarettes in adults was published in the literature.

Adult↗
PubMed2005

A peptide preparation protects cells in organotypic brain slices against cell death after glutamate intoxication.

Cerebrolysin has been shown to have neurotrophic and neuroprotective potential similar to NGF or BDNF. In the present study organotypic brain slices were utilized to determine the neuroprotective effects of Cerebrolysin, in a glutamate lesion paradigm mimicking a key event in ischemia. The study focused on the effects of Cerebrolysin on both necrotic and apoptotic cell death. Two specific DNA intercalating dyes were used to distinguish the type of cell death. The drug effect was evaluated both microscopically and quantitatively before, 24 hours after and then again 8 days after the lesion. Cerebrolysin was added either before and after the lesion or after the lesion only. The most pronounced effect was seen with the drug added both prior to and after the glutamate lesioning. A treatment after the lesion only also counteracted necrosis and apoptosis. The results render the drug relevant for treating acute as well as chronic neurodegenerative diseases.

Amino Acids↗
PubMed2000

A brain derived peptide preparation reduces the translation dependent loss of a cytoskeletal protein in primary cultured chicken neurons.

Neuronal cytoskeletal proteins like the microtubule associated protein 2 (MAP2) are objected to pathological proteolysis in case of Alzheimer's disease and brain ischemia. The neurotrophic peptidergic drug Cerebrolysin (EBEWE Arzneimittel, Austria, Europe) is produced by a standardized enzymatic break-down of lipid free porcine brain proteins. Cerebolysin protected MAP2 in primary neuronal cultures after a brief histotoxic hypoxia and in a rat model of acute brain ischemia. Furthermore the drug was shown to inhibit the proteases mu- and m-calpain dose dependently in several cell free protease activity assays. The question if the higher MAP2 levels are due to an alleviation of proteolysis, to a higher synthesis rate or both is addressed in the current investigation: Monitoring the MAP2 content of primary neuronal cell cultures over a period of eight days revealed MAP2 to reach a peak level on day six in vitro followed by a degradation phase. In other experiments the protein synthesis of Cerebrolysin treated and untreated cells was blocked with cycloheximide at that moment when all cells exhibited the same MAP2 content. After the following MAP2 degradation phase--i.e. after eight days in vitro--the MAP2 contents were determined by western blotting. Cerebrolysin treated cells contained more MAP2 than untreated controls proving that the drug protects MAP2 independently from de novo synthesis, although further work is in progress to investigate if the drug supplementary boosts this effect by increasing MAP2 synthesis.

Amino Acids↗
PubMed2000

Inhibitory effect of a brain derived peptide preparation on the Ca++-dependent protease, calpain.

Overactivated calpain might be a key factor in destruction of cytoskeletal proteins involved in the pathophysiology of ischemia and disorders like Alzheimer's disease. Therapeutic effects imply the possible interference of Cerebrolysin (Ebewe Arzneimittel, Austria) with these molecular events. In this work several in vitro methods have been applied to investigate the interaction between Cerebrolysin and calpain [Enzyme Commission (EC) number: 3.4.22.17]. A conventional caseinolytic assay beside two flourimetric assays using a synthetic peptide substrate and a fluorescence labelled cytoskeletal protein [microtubule-associated protein 2 labelled with 5-([4,6-dichlorotriazin-2-yl]amino) fluorescein (MAP2-DTAF)] respectively for a highly sensitive fluorimetric calpain activity assay were applied for kinetic analysis. The caseinolytic assay showed that the drug inhibits both mu- and m-calpain and to a significantly lower extent also trypsin [Enzyme Commission (EC) number: 3.4.21.1] and papain [Enzyme commission (EC) number: 3.4.22.6]. Dialysis experiments revealed Cerebrolysin mediated calpain inhibition to be reversible. Kinetic analysis exhibited a non-competitive, or tight-binding competitive, mode of inhibition. This latter mode, substantiated by serial dilution experiments, and the likely existence of calpastatin in a brain derivative suggests the occurrence of calpastatin fragments or calpastatin-like fragments in Cerebrolysin. The clearly competitive inhibition of trypsin by the drug indicates distinct mechanisms and active components against different proteases.

Amino Acids↗
PubMed1989

[Defibrination syndrome after snake bites].

A defibrination syndrome developed in two men (aged 51, and 29 years old) within two hours of having been bitten by vipers Echis carinatus and Agkistrodon halys, respectively. In both the syndrome was characterized by afibrinogenemia with prolongation of the thrombin time, presence of fibrin monomers and split products of fibrinogen. Haemorrhagic signs included oral mucosa bleeding and macrohematuria. Specific serum was administered 9 and 16 hours, respectively, after the bite and achieved normalization of all clotting values within 48 hours.

Adult↗
PubMed1983

Near fatal percutaneous paraquat poisoning.

A fatal paraquat poisoning can occur when relatively large areas of skin are contaminated with a concentrated solution of paraquat (Gramoxone). A paraquat absorption takes place of the same magnitude as that with an equal dose per os. In the presence of mechanical or chemical lesion of the skin the percutaneous paraquat absorption is distinctly enhanced.

Accidents, Home↗
PubMed1979

[Plasma aldosterone and electrolytes in primary and secondard aldosteronism (author's transl)].

Plasma aldosterone levels and the serum electrolytes potassium, sodium and magnesium of 38 patients with healthy adrenals were determined. Under physiological conditions there were no significant correlations between these parameters. In two patients with an aldosterone producing adenoma of the adrenals (syndrome of Conn) we found very low levels of potassium and low levels of magnesium. The levels of sodium lay in the upper normal range. Plasma aldosterone levels are raised strongly. After resection of the tumors the mentioned parameters normalized. In 16 patients with cirrhosis and ascites we generally found values of aldosterone, potassium, sodium and magnesium which lay in the lowest normal range. Under treatment with spironolactone the aldosterone levels raised and reached values which are characteristical of the syndrome of Conn. Potassium raised to the upper normal range, magnesium raised significantly, sodium diminished slightly.

Adenoma↗
PubMed1977

[An unusual case of panarteritis nodosa associated with chronic mercury poisoning (author's transl)].

In a 50-year-old woman, working as a dental assistant for more than ten years, chronic mercury poisoning developed insidiously, apparently from careless handling of mercury-amalgam. The main signs consisted of mental and neurological changes such as erethism, tremor and mercurial psellism. Peripheral arterial circulatory disorders occurred in the course of the disease, as well as abdominal colic and a polyneuropathy, which provided the first clues to panarteritis nodosa subsequently confirmed histologically.

Biopsy↗