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Biomedical subjects

H Bischoff

Publications and source records attributed to H Bischoff.

45 records · Page 3Linked to original sources
PubMed1986

Autochthonous, acetoxymethylmethylnitrosamine-induced colorectal cancer in rats: a useful tool in selecting new active antineoplastic compounds?

Acetoxymethylmethylnitrosamine (AMMN)-induced autochthonous colorectal rat adenocarcinomas are an interesting model for the secondary evaluation of new antineoplastic compounds aimed at predicting clinical activity. These orthotopic tumors mimic the human situation closer than conventionally used transplanted systems with respect to their relatively slow growth, their genuine histology, their original tumor-host interaction and their low chemosensitivity to clinically used drugs. 4-Amino-N-(2' aminophenyl) benzamide, 4-Oxo-2-phenyl-4H-1-benzopyran-8-acetic acid, dichloro-bis(1-phenyl-1,3-butanedionato)titanium(IV) and diethoxy-bis(1-phenyl-1,3-butanedionato)titanium(IV) are four new agents, which have shown promising anticancer activity in this model, but which failed to show high activity in fast-growing transplanted systems. Clinical studies on these agents are highly warranted. A comparison of predicted and actual clinical anticancer activity will finally point to the appropriate means of drug selection.

Adenocarcinoma↗
PubMed1985

[Single-dose treatment of acute cystitis with norfloxacin. 1st report].

25 women with acute uncomplicated cystitis were treated with a single dose of 800 mg norfloxacin orally. Urinary checkups were performed 3 and 8 days after therapy and 4 and 8 weeks later. Urinary cultures, bacterial identification and antibiotic testing were performed. Success rate as based on the bacterial results was 96%. Reinfection occurred in one case only over the follow-up period of 8 weeks. This high success rate is due to strict selection of patients with truly uncomplicated cystitis and the beneficial chemotherapeutic effect of norfloxacin.

Adult↗
PubMed1985

Synthesis, toxicity, and therapeutic efficacy of 4-amino-N-(2'-aminophenyl)-benzamide: a new compound preferentially active in slowly growing tumors.

The present paper describes 4-amino-N-(2'-aminophenyl)benzamide (GOE1734) with regard to synthesis; toxicity in mice, rats, and dogs; and differential therapeutic efficacy in slowly and rapidly proliferating rat tumors. GOE1734, an analog of a group of compounds known for other than antitumor effects with relatively simple N-acyl-O-phenylenediamine structure, is characterized by a low bacterial mutagenic potential after in vitro metabolic activation and DNA-DNA crosslinking activity after in vivo treatment. Maximum tolerated doses in rats and dogs amount to 4 and 1 mg/kg, respectively. High growth-inhibiting efficacy was obtained in intratibially implanted osteosarcoma, in methylnitrosourea-induced primary mammary carcinoma, and in acetoxymethyl-methylnitrosamine-induced colorectal adenocarcinoma. GOE1734 proved to be ineffective in transplanted Yoshida sarcoma and Walker 256 carcinosarcoma when single or multiple doses were administered at dose levels that were moderately toxic or not toxic. Some antitumor effects were observed in L5222 leukemia after ip transplantation, but no effect could be observed after ic implantation or in vitro incubation and subsequent retransplantation of these cells. Since the latter three rat tumors are characterized by relatively short tumor volume doubling times (0.5-2 days), whereas the first three grow slower (tumor volume doubling time, 11-19 days), the remarkable differential antitumor activity of GOE1734 in fast and slowly growing malignancies is striking.

Animals↗
PubMed1982

Effect of brain growth stages on T-maze acquisition in mice.

Recently, it has been shown that brain growth is characterized by periods of especially large increases in growth, with "plateaus" in growth between these "spurt" periods. In humans, these spurts in brain growth are correlated with spurts in mind growth, collectively termed phrenoblysis. Brain growth spurts in rodents occur at 0-6, 8-12, and 17-23 days of age with plateaus in-between. We examined two questions. First, are there differences in learning ability associated with spurts and plateaus in brain growth? Second, can learning during these stages be altered through genetic and environmental manipulations? We employed the high and low lines of the Fuller brain weight selection mice, which are known to have different developmental patterns, and early handling procedures, known to alter growth rates. The results showed that animals tested during a proposed brain growth spurt were superior to animals tested during a brain growth plateau in learning a shock-escape T-maze.

Age Factors↗
PubMed1980

[Myocardial protection by a carnosine-buffered cardioplegic solution (author's transl)].

A carnosine-buffered, Na+-poor and Ca2+-free cardioplegic solution with pH 7.40 and physiological osmolarity was developed. The effect on the myocardium was more protective than that obtained with a corresponding unbuffered solution or a Mg-aspartate-procaine solution. The metabolic state of rabbit hearts was investigated up to 8 h of ischemia at 15 degrees C. A constant glycolytic rate was observed up to 6 h and the ATP content was maintained at 83% of controls. The ratio of glycolytic ATP production vs. total turnover of high-energy phosphates was 0.85. The small difference between energy demand and production may effect the conditions for good recovery.

Adenosine Diphosphate↗