Biomedical subjects

F Bischoff

Publications and source records attributed to F Bischoff.

At least 37 records · Page 2Linked to original sources

PubMed1977

Intraperitoneal foreign body reaction in rodents.

In five experiments with female Marsh mice and male and female Evans rats, open-end cylinders of tin were implanted intraperitoneally with litter mates serving as surgical controls. The experiments were terminated 18-24 months later. The long-term local intraperitoneal foreign-body reaction with some cylinders remaining unanchored, frequent failure to develop a fibrous capsule at the outside of the tin cylinder, and a degree of lympho-histiocytic involvement and adenomatous hyperplasia in the fibrosis within the tin cylinder differed from the foreign-body reaction at the subcutaneous site characterized by avascular, cell-poor fibrosis with fibroblasts. In all the implanted rat series, a significant number of local sarcomas, 30-50% of which metastasized, developed with none in the corresponding controls. The incidences of spontaneous lymphoid tumors were decreased or not increased for the tin-implant series as compared with controls. This indicated that the local solid-state carcinogenic process was only partially, if at all, dependent upon the cell type (lymphocyte) that demonstrated a spontaneous inherently malignant potential.

Animals↗

PubMed1977

Short- and long-term effects of a massive dose of 6-OH-DA upon marsh mice.

Single, sublethal subcutaneous doses of 6-hydroxydopamine (6-OH-DA) were given to young adult male and female Marsh mice. The ability of 6/8 males to sire 15 or more days later was not abolished. Of 10 females dosed during pregnancy, 6 failed to deliver and lost substantially in body weight. Of the 4 that delivered, 2 cannabalized their young. The offspring of the 6-OH-DA-dosed fathers and mothers showed no gross anatomical defects nor lessened survival rates. Confrontation of 6-OH-DA-dosed males with control males as pairs demonstrated increased anal sniffing as compared with control-pair confrontation. In a long-term series with males, liver anomalies including tumor development were demonstrated for 6-OH-DA. Lymphoid tumor induction was not affected. However, 3 local fibrosarcomas and 1 intrasorbital giant cell sarcoma arose. A sublethal dose of L-dopa had no lasting effect on male mouse aggression nor on other behavioral manifestations that would implicate 6-OH-DA formation as a metabolic route.

Aggression↗

PubMed1976

Toxicologic studies of tin needles at the intrathoracic site of mice.

Male Marsh mice which received a single intrathoracic injection of 4 mg of tin needles at 3 months of age were compared with controls given isotonic saline. The form and size of most of the tin needles were similar to those of asbestos needles which produced mesotheliomas and lung neoplasms in rodents. Water and food intake was markedly reduced for 24 hrs after the injection of tin. Survival rates (followed for 19 months), pathology of the bladder, liver, and kidney, as well as local and general cancer development were not adversely associated with the tin treatment as compared with the tin treatment as compared with controls. The local reaction to the tin included giant cell phagocytosis, nodular fibroplasia, and capillary formation. The failure of the tin needles to induce local neoplasms may relate to their high density as compared with silicates and/or their lack of the unique potential of the silicate particles to stimulate avascular fibrosis.

Animals↗

PubMed1975

Male mouse aggression as a pharmacologic model.

At 5 to 8 months of age the fighting and tail-rattling of male Marsh mice during paired confrontations was significantly greater for isolated than for mice prehoused in groups of males or in groups of one male with females. The differences were not significant for treatment effects tested in a similar manner with mice 11 to 12 months of age. At 5 months of age, mounting behavior of pregrouped males on paired confrontation was significantly less than that of isolated males. Paper towels instead of pine shavings for bedding abolished test-fighting for isolated mice. In any model with randomly sampled groups, an inherently highly aggressive mouse (killer) required to be eliminated from the grouped series, is not detected in the isolated series. These considerations challenge the use of isolated male mice as a pharmacologic model for evaluating behavior-modifying drugs. A four-fold difference in the area of prehousing cages of isolated males did not influence aggressive behavior. Fights correlated with tail-rattling; r equals 0.93 over the 14 series studied.

Age Factors↗

PubMed1975

Cholesterol plate deposition in a pathological transport environment.

Triglycerides separated from human serum lipoprotein or triolein converted cholesterol needles to plates on equilibration in isotonic saline. Cholesterol needles equilibrated with human clear or lipemic plasma or serum were not converted to plates unless olive oil or triolein was added. Plasma phospholipid permitted and sodium lauryl sulfate (0.1-10%) prevented formation of plates from cholesterol needle-saturated olive oil in water at 38 degrees C. Cholesterol liquid crystals, formed from needles dispersed in aqueous plasma phospholipid, changed to plates on dilution with water. The cholesterol content of lipemic and high-, normal-, or low-cholesterol sera, equilibrated with cholesterol plates at 38 degrees C, was not significantly altered. In rats and mice the mobilization of injected cholesterol needles at the intrathoracic site manifested a sex-species difference. In the pathological deposition of cholesterol plates, a breakdown of a defense mechanism in plasma involving noncovalent binding of triglyceride with phospholipid and protein is indicated.

Animals↗

PubMed1974