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The well-documented existence of interspecies differences in the responses elicited by exposure to chemical agents (1–3) represents the main difficulty in the extrapolation to humans of the results of toxicity studies carried out in laboratory animals or in in vitro systems employing ...

This test is designed to detect irreversible toxic effects on both cell growth and survival, by the evaluation of colony-forming (CF) efficiency, in hepatoma cell lines derived from humans, rat, and mouse. The liver is a major target organ for the cytotoxicity of many xenobiotics. It has been sugges ...

The model cavity method enables the in vitro cytotoxicity testing of dental restorative materials that may then be related to dental toxicity likely to occur in vivo.

The cytotoxic effect of chemicals on cells in culture is measured by the change in total cell protein (Kenacid Blue R dye binding method). Healthy 3T3-L1 cells (an established cell-line, ATCC CCL92.1), when maintained in culture continuously divide and multiply over time. The basis of this test is t ...

The membrane theory of toxicity (1) emanates from the fact that the plasma membrane is the first barrier met by a toxic agent on reaching the cell, and was first advanced to explain the toxic effects of heavy metals. The vital regulatory mechanisms inherent in the plasma membrane and its chemical compo ...

The Allium test provides a rapid screening procedure for chemicals, pollutants, contaminants, and so on that may represent environmental hazards. Root growth inhibition and adverse effects on chromosomes provide an indication of likely toxicity.

The MTT calorimetric assay determines the ability of viable cells to convert a soluble tetrazolium salt (MTT) into an insoluble formazan precipitate. Tetrazolium salts accept electrons from oxidized substrates or appropriate enzymes, such as NADH and NADPH. In particular, MTT is redu ...

In this test, rabbit-derived cornea1 cells are cultured in the presence of test compounds, the toxicity of which are determined by their effects on cell viability. A decrease in cell number, as measured by uptake of the dye Neutral Red, serves as an indicator of potential cytotoxicity. This test has be ...

The cytotoxic effect of test chemicals in V79 cell culture can be determined by assessing damage to the plasma membrane as determined by a nucleic acid leakage assay.

The cytotoxic effect of chemicals on Balb/c 3T3 cells in culture is measured by cell viability (Neutral Red Uptake) and total cell protein (Kenacid Blue R dye binding method). Healthy Balb/c 3T3 cells (an established cell line), when maintained in culture, continuously divide and multiply over t ...

In this test, rabbit articular chondrocytes are cultured in the presence of a test compound, the toxicity of which is then determined by its effect on the production of proteoglycan by the cells, as detected by the dye Alcian Blue.

Over the last few years several groups of workers have endeavored to devise a replacement for the Draize eye test (1) in order to reduce the numbers of experiments carried out in vivo in fulfillment of safety requirements for medicinal preparations, toiletries, and cosmetics that might, either by ...

The potential irritancy of compounds may be detected by observing adverse changes that occur in the chorionallantoic membrane of the egg after exposure to test chemicals (1).

In monitoring possible cytotoxic effects of bioactive chemicals, it is desirable to have easy and sensitive test systems. The in vitro culture of pollen can provide a sensitive indication of toxicity at the cellular level, since germination and growth of pollen tubes are inhibited in the pres ...

In the search for valid alternatives to animals in assessing the acute toxicity of substances foreign to humans, the use of cells in vitro is a sound proposition. The validity of any in vitro model is limited, however, because the physiological, immunological, and inflammatory conditions in vivo ...

Neuroepithelial cells of the central nervous system constitute neuroglia (astrocytes, oligodendrocytes, and microglia), ependyma, and neurons, which make up the stromal cells of the brain. The stromal tissue organization of the brain is tightly regulated, but occasionally the sig ...

The Wnt/β-catenin signaling pathway is tightly regulated and has important functions in development, tissue homeostasis, and regeneration. Deregulation of Wnt/β-catenin signaling is frequently found in various human cancers. Eighty percent of colorectal cancers alone reve ...

Antisense oligonucleotides (ASO) against specific molecular targets (e.g., Bcl-2 and Raf-1) are important reagents in cancer biology and therapy. Phosphorothioate modification of the ASO backbone has resulted in an increased stability of ASO in vivo without compromising, in gener ...

Heterotrimeric G proteins attached to the cell membrane convey signals from G protein-coupled receptors in response to stimulation by a number of hormones, neurotransmitters, chemokines, and pharmacological agents to intracellular signaling cascades. The heterotrimeric G ...

Along with the emergence and development of the new field of “proteomics,” neuroscientists together with other life scientists have been offered the greater opportunity to clone and sequence new biologically active proteins and to assess alterations in protein expression at both mRNA ...