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A M Goldberg

Publications and source records attributed to A M Goldberg.

At least 19 recordsLinked to original sources
PubMed2001

The TestSmart-HPV Program--development of an integrated approach for testing high production volume chemicals.

The TestSmart program was developed in response to the High Production Volume Chemical Challenge, a voluntary initiative under which chemical producers provide basic toxicity data on chemicals produced in greater than one million pounds annually. Specifically, under the Challenge, chemical producers will generate data as needed to complete the Screening Information Data Set (SIDS), as defined by the Organization for Economic Cooperation and Development (OECD). The TestSmart program is a collaborative effort of the Johns Hopkins Center for Alternatives to Animal Testing, the Environmental Defense Fund, Carnegie-Mellon University, and the University of Pittsburgh. The goal of the TestSmart program is to provide a humane and efficient approach to collecting SIDS data. The program has two objectives, one immediate and the other more long term. The immediate objective has been to make recommendations to reduce the number of animals used in collecting SIDS data under the Challenge. This was accomplished, through a group process, by examining the current status of alternative methods for SIDS endpoints and by providing an assessment of the "state of readiness" of current and potential future alternatives. The long-term objective is to provide a model for other programs to follow the TestSmart concept of a more efficient and humane approach to obtain toxicological data of interest to regulators and the public.

Animal Testing Alternatives↗
PubMed2000

The effects of pH and PEG 400-water cosolvents on oxytetracycline-magnesium complex formation and stability.

The effects of pH and PEG 400 on the stoichiometry, conformation, and stability of the magnesium-oxytetracycline (Mg+2-OTC) complex were evaluated. Circular dichroism (CD) and HPLC were used to investigate Mg+2-OTC complex formation and determine the stability of the complexes formed. The stoichiometry of the complex was determined to be a 1:1 molar ratio of Mg+2 to OTC regardless of changes in pH, in the range 7-10, and regardless of the percentage of polyethylene glycol (PEG) 400 in solution. CD showed that the conformation assumed by Mg+2-OTC complex is sensitive to changes in pH, however, little to no effect was found when the PEG 400 concentration was varied. PEG 400 was found to effect the magnitude of complexation as evident by the dependence of CD peak intensity on the cosolvent concentration in solution. The Job's method confirmed that the formation of this complex increased with increasing PEG 400 concentration and was most favored at pH 8. HPLC analyses of OTC solutions at pH 9 revealed the formation of multiple degradation products after storage at 50 degrees C. The incidence and magnitude of OTC degradation products were reduced in the presence of Mg+2 and PEG 400. Despite the HPLC results of maintained OTC stability in magnesium-complexed solutions over time, visual inspection showed these solutions to have darkened, indicating that an oxidative process is responsible for initial degradation of OTC. Therefore, the need for additional measures (i.e., antioxidants) was established to ensure the long-term stability of OTC in solution.

Algorithms↗
PubMed1998

Dermal toxicity: alternative methods for risk assessment.

Conceptually, irritant contact dermatitis (irritation) and allergic contact dermatitis (ACD) in man should provide the ideal platforms to launch in vitro toxicology into the pantheon of in vitro testing assays. In theory, irritant dermatitis has been considered by most a simple area of cutaneous biology, whereas ACD is a complex area of biology. However, both result in responses that are reasonably stereotypical and well characterized. The biology of the underlying mechanisms is becoming characterized and will thus allow development of mechanistically based in vitro assays that will be scientifically validated and thus acceptable to regulatory agencies.

Animal Testing Alternatives↗
PubMed1995

Development of alternative methods.

This presentation will raise specific issues and explore areas that need discussion and development of mechanistically based tests in toxicology. In addition, an approach to validation will be presented that is based on fundamental principles and modeled after actual practice in other areas of methodology acceptance. Further, it is recognized that the validation process is but only one aspect of incorporation of in vitro approaches into safety-evaluation and risk assessment.

Animal Testing Alternatives↗
PubMed1993

Framework for validation and implementation of in vitro toxicity tests.

The development and application of in vitro alternatives designed to reduce or replace the use of animals, or to lessen the distress and discomfort of laboratory animals, is a rapidly developing trend in toxicology. However, at present there is no formal administrative process to organize, coordinate, or evaluate validation activities. A framework capable of fostering the validation of new methods is essential for the effective transfer of new technologic developments from the research laboratory into practical use. This committee has identified four essential validation resources: chemical bank(s), cell and tissue banks, a data bank, and reference laboratories. The creation of a Scientific Advisory Board composed of experts in the various aspects and endpoints of toxicity testing, and representing the academic, industrial, and regulatory communities, is recommended. Test validation acceptance is contingent on broad buy-in by disparate groups in the scientific community--academics, industry, and government. This is best achieved by early and frequent communication among parties and agreement on common goals. It is hoped that the creation of a validation infrastructure composed of the elements described in this report will facilitate scientific acceptance and utilization of alternative methodologies and speed implementation of replacement, reduction, and refinement alternatives in toxicity testing.

In Vitro Techniques↗
PubMed1993

Report of the Validation and Technology Transfer Committee of the Johns Hopkins Center for Alternatives to Animal Testing. Framework for validation and implementation of in vitro toxicity tests.

The development and application of in vitro alternatives designed to reduce or replace the use of animals, or to lessen the distress and discomfort of laboratory animals, is a rapidly developing trend in toxicology. However, at present there is no formal administrative process to organize, coordinate, or evaluate validation activities. A framework capable of fostering the validation of new methods is essential for the effective transfer of new technological developments from the research laboratory into practical use. This committee has identified four essential validation resources: chemical bank(s), cell and tissue banks, a data bank, and reference laboratories. The creation of a Scientific Advisory Board composed of experts in the various aspects and endpoints of toxicity testing, and representing the academic, industrial and regulatory communities, is recommended. Test validation acceptance is contingent upon broad buy-in by disparate groups in the scientific community-academics, industry and government. This is best achieved by early and frequent communication among parties and agreement upon common goals. It is hoped that the creation of a validation infrastructure composed of the elements described in this report will facilitate scientific acceptance and utilization of alternative methodologies and speed implementation of replacement, reduction and refinement alternatives in toxicity testing.

Animal Testing Alternatives↗
PubMed1992

Status of in vitro ocular irritation testing.

This paper reviews advances in the validation of alternative methods for eye irritation testing since the 1987 publication, A Critical Evaluation of Alternatives to Acute Ocular Irritation Testing (1). We have highlighted details of methods that appear promising and identified the minimum needs and endpoints necessary to develop a battery or batteries of in vitro tests to evaluate eye irritancy. We have recommended a series of workshops to provide identified batteries for specific classes of chemicals or for specific uses of eye irritancy testing. We have also identified the need for consensus meetings and peer-reviewed publication to ensure that the most predictive batteries become parts of validation studies. Finally, we note that academic scientists, industry, government and the animal protection community must work together in order to replace in vivo eye irritancy testing with appropriately validated in vitro methods.

Allantois↗
PubMed1985

An approach to the development of in vitro toxicological methods.

Over the last few years there has been increased societal pressure on the one hand and self-generated scientific pressure on the other to develop new and better in vitro techniques for the evaluation of the safety of commercial products. In vitro methodology addresses four major areas within toxicology. It provides the basic science of the discipline with new information. In acute toxicity testing, it can provide alternatives to current approaches, e.g. the Draize irritation tests. In the area of chronic toxicity testing, it will allow us to define the mechanisms associated with organ specific insults. In the area of risk assessment, the combined knowledge obtained by superior methods will allow us to assess risk more accurately. The results of studies on alternatives to the Draize irritation tests being carried out at or supported by The Johns Hopkins Center for Alternatives to Animal Testing will be reviewed.

Animal Testing Alternatives↗
PubMed1984

Perturbation of a hippocampal zinc-binding pool after postnatal lead exposure in rats.

Morphologic alterations of the hippocampal mossy fiber pathway after postnatal lead exposure have been observed in rats. It is hypothesized that lead might perturb zinc pools found in this pathway. To test this hypothesis, rat pups were exposed to lead indirectly by administering 0.2% lead acetate to dams via the drinking water during lactation for 21 days and control litters were maintained on tap water. To evaluate whether or not the effects of postnatal lead exposure were selective for hippocampal zinc pools, the hippocampus was compared with the cerebellum. There were no significant differences between lead-treated and control rats in total zinc content in either the hippocampus or the cerebellum in rats at 30 and 90 days of age. Furthermore, no differences in the subcellular distribution of zinc were observed between control and lead-treated animals. Because the effects on zinc content may be more subtle, the amounts of cytosolic zinc-binding species, isolated using Ultrogel AcA 34 gel chromatography, were measured in control and lead-treated animals. A striking decrease was observed in the amount of zinc associated with one of the cytosolic zinc-binding species, a putative zinc-glutathione complex, shown in previous studies to be the major hippocampal zinc pool. This effect was observed only in the hippocampus of 30-day-old lead-treated rats. By 90 days of age, the effect was no longer present. These data suggest that lead preferentially affects a zinc pool found in the hippocampus and supports our hypothesis that postnatal lead exposure results in an alteration in hippocampal zinc.

Animals↗
PubMed1984

The Johns Hopkins Center for Alternatives to Animal Testing.

The Center strives to develop new non-whole-animal test methodologies based on understanding mechanisms of toxicity of chemicals, consumer products, and drugs for the evaluation of safety. The Center will strive for scientific excellence, and to provide superior methods which will replace existing strategies.

Animal Testing Alternatives↗