Transforming growth factor-beta (TGF-beta) signaling requires a ligand-dependent interaction of TGF-beta receptors Tau beta R-I and Tau beta R-II. It has been previously demonstrated that a soluble TGF-beta type II receptor could be used as a TGF-beta antagonist. Here we have generated and investigated the biochemical and signaling properties of a soluble TGF-beta type I receptor (Tau beta RIs-Fc).
View Article and Find Full Text PDFCigarette smoke is known to generate free radicals by various mechanisms. In this study involving 30 non-smokers and 30 smokers, we show that urinary excretion of 5-(hydroxymethyl) uracil (HMUra) was not different in the two groups (6.54+/-2.
View Article and Find Full Text PDFWe measured the base 5-(hydroxymethyl) uracil (HMUra) and the nucleoside 8-oxo-7,8-dehydro-2'-deoxyguanosine (8-oxo-dGuo) in urine of adriamycin-treated cancer patients. Adriamycin has been shown to generate oxygen free radicals by various mechanisms. HMUra and 8-oxo-dGuo are two known lesions of DNA, produced by oxygen free reaction on thymine and 2'-deoxyguanosine, respectively.
View Article and Find Full Text PDFA 32P-postlabelling assay has been developed for singling out specific oxidized base lesions. Emphasis was placed on the quantitative aspect and the accuracy of the assay, which require the use of calibration curves and microreactions, respectively. The method was successfully applied to the detection and the measurement of adenine N1-oxide and 5-hydroxymethyluracil in cells exposed to agents inducing oxidative stress including H2O2 and UV-A radiation.
View Article and Find Full Text PDFThe bacterial extract IMOCUR is described as an in vivo stimulant of antibody production during animal testing and human clinical trials. Using a slightly modified procedure (13) dealing with in vitro immunoglobulin production by C57B1/6 mouse spleen cells, we have shown that IMOCUR potentiates spontaneous IgM production. In order to explore the putative relation between this in vitro activity and the current in vivo control test (stimulation of plaque-forming cell production after sheep red blood cell injection to Balb/c mouse), we have assayed 10 lyophilisates in vitro and in vivo before and after heat inactivation (80 degrees C, 7 days in a saturated water atmosphere).
View Article and Find Full Text PDFBiol Trace Elem Res
January 1990
In this paper we report a method for measuring ultrafiltrable zinc in human serum by electrothermal atomic absorption spectrophotometry. We show also that ultrafiltration permits to determine alpha-2-macroglobulin bound zinc and loosely bound zinc if a strong zinc ligand (EDTA) is added to serum before ultrafiltration. This last fraction, after deduction of ultrafiltrable zinc, represents roughly all albumin bound zinc.
View Article and Find Full Text PDFThe Onderstepoort strain of canine distemper virus (CDV) which has been adapted to newborn Swiss mice was used in a study in weanling mice. Intracerebral inoculation of newborn mice with either the parent or mouse-adapted virus strain led to mortality in 100% of the animals. In weanling mice the parent virus produced less than 10% mortality, whereas the mouse-adapted strain killed approximately 40% of the animals and this was not dose-dependent.
View Article and Find Full Text PDFA study on hexachlorophene encephalopathy in mice and baboons is reported. By light microscopy, a severe spongiform lesion of the central nervous system (CNS) was localized in the white matter, without myelin breakdown or cellular reaction. By electron microscopy, the myelin alteration was characterized by wide intralamellar spaces or "splitting" developed in the intraperiod line of compact sheaths.
View Article and Find Full Text PDFAn experimental study on acute Hexachlorophene (HCP) neurotoxicity is reported in mice and baboons: - by light microscopy, a severe spongiform lesion of the central nervous system is localized in the white matter without myelin breakdown or cellular reaction; - by electron microscopy, the myelin alteration is characterized by the presence of vacuolation of "splitting" in the intralamellar spaces of compact sheaths; myelinated axons are occasionally involved. The changes described are discussed according to various reports on HCP neurotoxicity in humans and experimental animals. The effects of this chemical agent on the central nervous system is related to the percentage of HCP in talcum powder or solution for topical use.
View Article and Find Full Text PDFC R Seances Acad Sci D
September 1980
Induction of synthesis of the viral antigens T and V during polyoma virus infection was studied in primary Mouse and Hamster kidney and brain cultures, as well as in various types of human cells. The results show that: (1) Despite a very low percentage of positive cells by immunofluorescence, Hamster brain cells produced more viral antigen than kidney cells, as opposed to what was found in Mouse brain cells. (2) Most human cells produced neither T nor V antigens.
View Article and Find Full Text PDFThe morphological characteristics of three clones of hamster brain cells transformed in vitro by polyoma virus and of the tumors obtained after subcutaneous grafting of these cells in syngenic animals are reported. These clones appeared to be glial in nature by light and electron microscopy. The initial tumors induced by the three clones presented astrocytic features both by electron microscopy and immunohistochemistry.
View Article and Find Full Text PDFAn ultrastructural study was performed on normal and Benzo(a)-pyrene(B(a)P)-transformed fetal mouse brain cells. Early subcultures of a strain initiated from whole brain presented three cell types in vitro: astroglial, poorly differentiated glial, and spongioblastic types. After B(a)P-treatment, there was an exclusive transformation and the growth of neuroglia sometimes without gliofibrillary maturation, but with the presence of glial fibrillary acidic protein (GFAP) in the cytoplasm.
View Article and Find Full Text PDFPrimary cultures of whole brain and cortex cells origination from 14-day-old A/Jax or C3H mouse fetuses were treated with benzo(a)pyrene (B(a)P) for 24 h. After 7 to 8 passages a malignant transformation was observed in the chemically treated whole brain and cortex cultures. Control cultures of cortex remained non-transplantable during the whole experiment (up to 14 passages) whereas in the control cultures originating from whole brain a spontaneous transformation appeared after 11 passages.
View Article and Find Full Text PDFOne case of meningiothelial meningioma with "hyaline inclusions" (colloid-bodies or pseudopsammomas) as noted by Cushing and Eisenhardt (1938) and by Kepes (1961-1975) is reported by light and electron microscopy. Two types of these structures, either homogeneous or polymorphic, surrounded by microvilli are described and regarded as signs of secretory differentiation of tumor cells. In addition to Kepes' description, the authors show, at high magnification, the polymorphic material including homogeneous component, lamellar structures, microvesicles and dense bodies.
View Article and Find Full Text PDFThe transformation of cultivated hamster brain cells by polyoma virus is reported. The transformed cell line contained polyoma virus-specific nuclear, surface and transplantation antigens. Subcutaneous and intracranial inoculations revealed high tumorigenicity of the cells.
View Article and Find Full Text PDFRev Electroencephalogr Neurophysiol Clin
August 1978
C R Acad Hebd Seances Acad Sci D
September 1977
Using primary cultures originating from 14 day old fetal Hamster brain, we have obtained a cell line with glial morphology. These cell remain non transplantable during the first year of in vitro culture, but undergo spontaneous transformation during the second year. Following prolonged contact of the glial-like cells with 25 to 50 microgram/ml of methylnitrosourea (MNU), a malignant transformation is observed 5 months after the treatment.
View Article and Find Full Text PDFC R Acad Hebd Seances Acad Sci D
March 1977
A cell line called HCxPy was obtained in vitro by transformation of dissociated hamster brain cell cultures by polyoma virus. The first foci of transformed cells became evident 90 to 120 days after viral infection. This cell line is now at the 46th passage.
View Article and Find Full Text PDFThe authors report electron-microscopic observations upon a primitive cerebral haemangiopericytoma. The vascular appearance of the tumour is due to the presence of abundant extracellular material which has a structure like that of vascular basement membranes. The fact that the tumour cells are pericytes is confirmed by the existence of intracytoplasmic microfilaments of 60-80 A in diameter, sometimes gathered into osmiophilic aggregations and forming simple cellular junctions (zonulae adherentes).
View Article and Find Full Text PDFOne case of malignant tumour of the left nasal cavity is reported in a woman 56 year old, affected by the disease 24 years. Numerous recurrences appeared and various histological diagnoses were performed. At the last surgery, the tumour invaded the ethmoid and was a typical olfactory esthesioneurocytoma.
View Article and Find Full Text PDFC R Acad Hebd Seances Acad Sci D
February 1976
The authors report premilinary results of an experiment on permeability of the blood-brain barrier (BBB) to anti-tumor virus-induced immunological factors in the polyoma virus/Syrian Hamster system. The animals were protected by subcutaneous or intracranial injections with virus before challenge with polyoma virus transformed cells by both routes. BBB seemed to be permeable to the efferent part of the subcutaneously induced immune reaction.
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