M-CSF transgenic mice: role of M-CSF in infection and autoimmunity.

In this study, transgenic CD2F1 mouse lines (C-1.1-C-1.11) bearing a transgene encoding the murine growth factor M-CSF under the control of the liver specific alpha-1-antitrypsin gene promoter were generated.

A method for in vitro analysis of the biological activity of complex mixtures such as sidestream cigarette smoke.

Studies of the cytotoxicity of air contaminants such as gaseous or particulate compounds and complex mixtures have traditionally used in animal experiments because of the difficulties in exposing cell cultures directly to these substances. New cultivation and exposure techniques enhance the efficiency of in vitro methods, as demonstrated by a new system called CULTEX* which uses a transwell membrane technique for direct exposure of complex mixtures like sidestream cigarette smoke at the air/liquid interface. The factors influencing the susceptibility of human bronchial epithelial cells (e.

Effects of macrophage-CSF on pulmonary-macrophage repopulation after bone marrow transplantation.

Pulmonary infections are important causes of morbidity and mortality in immunosuppressed patients after transplantation. After experimental irradiation and syngeneic bone marrow transplantation in mice, macrophages show reduced repopulation in the lung compared with that in other tissues. Macrophages are major microbicidal immune effector cells in host pulmonary defense.

Verapamil metabolism in distinct regions of the heart and in cultures of cardiomyocytes of adult rats.

A substantial number of drugs act either directly or indirectly on the heart, but surprisingly, little is known about drug oxidation in the heart. We therefore investigated the metabolism of the calcium antagonist verapamil in microsomal fractions isolated from the left and right ventricle of heart muscle and in primary cultures of cardiomyocytes of adult rats. Metabolism of verapamil proceeded predominantly with microsomal fractions isolated from the right ventricle of rat heart, and in liquid chromatographic-tandem mass spectrometry (LC-MS/MS) and LC-MS(3) experiments four metabolites (M1-M4) could be identified.

Inhalation studies with the Göttingen minipig.

A method for inhalative exposure of minipigs to aerosols and gases has been developed. Minipigs are exposed via mask inhalation to the test substance using a computer-controlled exposure system that permits simultaneous exposure of groups of four animals in parallel to different controlled dose levels. We studied inhalation treatment of verapamil, a cardiovascular drug, and show good absorption and favorable pharmacokinetics when compared with iv drug application.

Reprogramming of gene expression in cultured cardiomyocytes and in explanted hearts by the myosin ATPase inhibitor butanedione monoxime.

Background: Butanedione monoxime (BDM) is a reversible myosin ATPase inhibitor. Its use in transplantation medicine may be of benefit in the preservation of hearts. As little is known about its ability to prevent stress and metabolic deregulation, we wanted to investigate the genomic response in cultured cardiomyocytes and explanted, preserved hearts at the transcriptional level.

Isolation and cultivation of Ca2+ tolerant cardiomyocytes from the adult rat: improvements and applications.

1. Primary cultures of cardiomyocytes provide a valuable tool for the study of the pharmacological and toxicological properties of drugs and chemicals, but for several technical reasons cardiomyocytes from adult animals are not routinely used in long-term culture. Because of significant advances in cardiovascular research, tissue engineering and cell transplantation, the need to isolate primary cells from adult animal and/or human tissue is likely to increase in the future.

Induction of nuclear transcription factors, cytochrome P450 monooxygenases, and glutathione S-transferase alpha gene expression in Aroclor 1254-treated rat hepatocyte cultures.

Aroclor 1254 is a complex mixture of polychlorinated biphenyls and is well known for its potency to induce drug-metabolising enzymes, but little is known about its ability to modulate gene expression of transcription factors, which code for proteins that bind to the regulatory elements of DNA and facilitate transcriptional activation. We therefore investigated the gene expression of the liver-specific transcription factors CCAAT/enhancer-binding protein alpha (c/EBPalpha), hepatic nuclear factor (HNF) 1 and 4, and major cytochrome P450 (CYP) isozymes in addition to glutathione S-transferase alpha 2 (GSTA-2) in cultures of primary rat hepatocytes. We found highly significant and dose-dependent increases of c/EBPalpha (up to 62-fold), HNF-1 (up to 7-fold), HNF-4 (up to 8-fold), and 50- and 4-fold inductions of GSTA-2 and CYP monooxygenases, respectively.

Molecular diagnosis of a familial nonhemolytic hyperbilirubinemia (Gilbert's syndrome) in healthy subjects.

Recent research has shown that congenital nonhemolytic low grade hyperbilirubinemias in patients with Gilbert's syndrome (GS) are linked to mutations in the TATA box upstream of the uridine 5'-diphosphoglucose glucuronosyltransferase (UGT1A1) gene leading to an impaired bilirubin glucuronidation. In routine clinical practice GS patients can, however, only be suspected by exclusion of other causes of hyperbilirubinemia or substantial liver diseases. We developed a new, sensitive, convenient, and economic polymerase chain reaction (PCR) method for the rapid and reliable identification of gene polymorphisms in the TATA box of the UGT1A1 gene using fluorescence resonance energy transfer (FRET).

Asbestos as reference material for fibre-induced cancer.

The objective of this paper is to review published data on the carcinogenicity of asbestos fibres with regard to the elucidation of a potential risk originating from exposure to man-made vitreous fibres (MMVF). Steps in the comparison of the two fibre classes are characterization of the fibres, pulmonary deposition, biodurability and biopersistence and a review of the cancer risk from asbestos fibres after inhalation in rats and humans. Various dust samples of chrysotile, crocidolite, and amosite were used as reference materials in studies with experimental animals.

Cytochrome P450 mono-oxygenase gene expression and protein activity in cultures of adult cardiomyocytes of the rat.

There are a substantial number of drugs acting either directly or indirectly on the heart, but surprisingly, little is known about the metabolic capacity of heart muscle cells. We therefore investigated the gene expression and protein activity of cytochrome P450 isozymes in cultures of adult cardiomyocytes of the rat. Semi-quantitative CYP gene expression pattern suggests CYP1A1 and CYP2B1/2 to be key players in cardiomyocytes and upon treatment with Aroclor 1254 approximate 4 fold inductions could be observed for both gene families, when compared with appropriate controls.

Gene expression in distinct regions of the heart.

Background: Cytochrome P450 mono-oxygenases bring about metabolism of many drugs, including verapamil, but no information is available on the metabolism of such drugs in the human heart.

Methods: We investigated the gene expression of major human cytochrome P450 mono-oxygenases in the various regions of explanted hearts from six patients with dilated cardiomyopathy and one with transposition of the arterial trunk. For comparison we also studied samples of liver and lung from three patients and two samples of normal heart.

Inhalation tolerance study for p-aramid respirable fiber-shaped particulates (RFP) in rats.

This study was designed to assess the lung clearance function in rats after subchronic exposure to p-aramid respirable fiber-shaped particulates (RFP). Male Wistar rats were exposed 6 hrs/day, 5 days/week for 3 months to 50, 200, and 800 RFP/ml measured by scanning electron microscopy (SEM). Recovery effects were followed up through 9 months postexposure.

Cellular dedifferentiation of endothelium is linked to activation and silencing of certain nuclear transcription factors: implications for endothelial dysfunction and vascular biology.

We investigated the gene expression of the nuclear transcription factors c/EBPalpha, GATA-2, and the silencer Oct-1 in conjunction with the gene expression of all major cytochrome P450 genes and of eNOS in cultures of endothelial cells of the rat. The purity of cultured endothelial cells was also confirmed by flow cytometry measurements of PECAM-1, a surface antigen of endothelial cells. Taken collectively, the gene expression and flow cytometry studies provide strong evidence for c/EBPalpha, GATA-2, and Oct-1 to play a key role in the cellular dedifferentiation of endothelial cells; gene expression of eight individual CYP genes in conjunction with protein activity could be significantly increased upon treatment with Aroclor 1254, a well-documented chemical inducer of a battery of genes.

Cytochrome P450 enzyme activity and protein expression in primary porcine enterocyte and hepatocyte cultures.

1. A method for the isolation and cultivation of porcine hepatocytes and porcine duodenal enterocytes for the investigation of drug oxidation reactions has been established. 2.

Investigation of Chronic Toxic and Carcinogenic Effects of Gasoline Engine Exhausts Deriving from Fuel without and with Ferrocene Additive.

Chronic toxic and carcinogenic effects of gasoline engine exhaust inhalation were investigated in rats. The exhaust from the combustion of commercial fuel containing 30 ppm ferrocene additive was compared to exhaust from the same fuel without ferrocene. This study was part of a procedure to get a special authorization for the use of ferrocene as gasoline additive according to the German Gasoline Lead Act.

Development of a cell culture model system for routine testing of substances inducing oxidative stress.

The toxicological model of oxidative stress is a mechanism which is currently thought to be involved in the formation and development of many serious human diseases. Little is known about cellular responses to oxidative damage and the related specific toxicological properties of substances such as chemicals or components of the polluted urban atmosphere. On the basis of biological pathways involved in cellular antioxidative mechanisms, we developed a biological model for studying the oxidative properties of substances.

Bioavailability of fine dispersed platinum as emitted from automotive catalytic converters: a model study.

Automobile exhaust catalytic converters emit fine dispersed elemental platinum, Pt (0), in the nanometer range coated on larger aluminium oxide carrier particles. A pre-requisite for a potential systemic toxic effect of the emitted platinum is its bioavailability which was investigated using laboratory animals. To this end, a model substance was synthesised which consisted of aluminium oxide particles < or = 5 microns onto which platinum particles > or = 4 nm were deposited by a calcination process.

Dysfunction of pulmonary surfactant in asthmatics after segmental allergen challenge.

Increased airway resistance in asthma may be partly due to poor function of pulmonary surfactant. This study investigated the inflammatory changes of bronchoalveolar lavage fluid (BALF) and the performance of BALF surfactant in healthy control subjects (n = 9) and patients with mild allergic asthma (n = 15) before and after segmental challenge. BALF was obtained for baseline values, and 24 h after challenge with saline solution in one lung segment and with allergen in another.

Comparison of cytoskeletal structures in glass-adherent and polyethylene terephthalate (PET) membrane-adherent human pulmonary fibroblasts.

In order to use microporous membranes as a culture substratum for later air/liquid exposures with human pulmonary fibroblasts, we were interested to find out whether the behaviour of cells grown on PET membranes differs from those cultured under conventional conditions. We therefore compared cytoskeletal structures of membrane-adherent and glass-adherent cells. There were no differences found between the cytoskeleton of cells grown on membranes or on glass.

Bioavailability of platinum emitted from automobile exhaust.

A model substance was used which is similar in respect to platinum content of exhaust particles emitted from a three-way-catalytic converter equipped engine. The bioavailability of platinum from such exhaust particles and the kind of platinum species formed in vivo were assessed. An in vitro solubility test showed a solubility of approximately 10 percent of platinum content of the model substance in physiological sodium chloride solution.

Cloning and chromosomal mapping of the human p53-related KET gene to chromosome 3q27 and its murine homolog Ket to mouse chromosome 16.

KET is a member of the newly discovered family of proteins that is related to the tumor suppressor p53. Here we describe the molecular cloning of a human cDNA of 4846 bp encoding a protein of 680 amino acids. The human KET protein shares 98% identity with the previously characterized rat homolog.

Odontogenic fibroma in Sprague-Dawley rats: a report of 2 cases.

Two cases of odontogenic fibroma occurring in aged Sprague-Dawley rats are described. Both neoplasms were associated with a maxillary incisor and had identical histomorphological features. They were composed of solid proliferations of primitive, dental pulp-like mesenchyme separated by areas of collagenization.

Spontaneous neoplasms of the nasal cavity in rats.

The histomorphological features of two adenocarcinomas and two adenomas of the nasal cavity observed in two female Wistar rats and a male Sprague-Dawley rat are described. In one of the Wistar rats, a second tumour, classified as an adenoma, occurred in the posterior part of the nasal cavity.