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Nirmala Bhogal

Publications and source records attributed to Nirmala Bhogal.

16 recordsLinked to original sources
PubMed2006

An analysis of the Home Office Statistics of Scientific Procedures on Living Animals, Great Britain 2004.

The 2004 Statistics of Scientific Procedures on Living Animals were released by the Home Office in December 2005. They indicate that, for the third year running, there has been a significant increase in the number of laboratory animal procedures undertaken in Great Britain, and that increasing numbers of animals are involved. The overall trends in the use of toxicological and non-toxicological procedures involving animals are described. Particular emphasis is placed on the production and use of genetically modified animals, the production of biological materials, and acute toxicity testing. The use of non-human primates and dogs is also discussed. The implications of these latest statistics are considered with reference to the implementation of the Three Rs and their consequences for animal welfare.

Animal Experimentation↗
PubMed2006

TGN1412: time to change the paradigm for the testing of new pharmaceuticals.

Clinical studies in human volunteers are an essential part of drug development. These studies are designed to account for possible differences between the effects of pharmaceutical products in preclinical studies and in humans. However, the tragic outcome of the recent Phase 1 clinical trial on TGN1412 casts considerable doubt over the relevance of this traditional drug development paradigm to the testing of therapeutic agents for human use. The role of alternatives to animal testing is considered, and a series of recommendations are made, which could ensure that clinical trials are well informed and based on the most relevant scientific information.

Amino Acid Sequence↗
PubMed2006

An update on TGN1412.

In the last issue of ATLA, we assessed whether the existing methods for assessing the safety and efficacy of new candidate medicines was adequate for the testing of humanised therapeutic agents. We made specific reference to the failed TGN1412 first-in-man study that took place earlier this year. This paper was circulated to experts and those involved in the development or testing of TGN1412. More recently, the Focus on Alternatives group has made a submission to the Expert Working Group that is currently considering how such incidences can be avoided in the future. Here, we provide an update of the events relating to the TGN1412 clinical trial.

Animals↗
PubMed2006

The relevance of genetically altered mouse models of human disease.

The impetus to develop useful models of human disease and toxicity has resulted in a number of large-scale mouse mutagenesis programmes. This, in turn, has stimulated considerable concern regarding the scientific validity and welfare of genetically altered mice, and the large numbers of mice that are required by such programmes. In this paper, the scientific advantages and limitations of genetically altered mice as models of several human diseases are discussed. We conclude that, while the use of some such mouse models has contributed considerably to an understanding of human disease and toxicity, other genetically altered mouse models have limited scientific relevance, and fewer have positively contributed to the development of novel human medicines. Suggestions for improving this unsatisfactory situation are made.

Animal Testing Alternatives↗
PubMed2006

The UK Food Standards Agency draft report on variability and uncertainty in toxicology: a response by FRAME.

At the request of the Food Standards Agency, the Committee on Toxicity of Chemicals in Food, Consumer Products and the Environment (COT) established a Working Group on Variation and Uncertainty in Toxicology (WG VUT). In April 2006, the WG VUT produced a draft report for public consultation. FRAME made a submission in response to this consultation in July 2006. We commend the WG VUT for its comprehensive account of many of the problems associated with risk assessment, and for making recommendations about the problems that need to be addressed. We were particularly encouraged by the WG VUTs recognition of the need for guidelines on how toxicological studies should be conducted and data analysed. However, we believe that the report has not achieved all of its objectives. It does not adequately consider how modern technologies, experimental design, statistical analysis and species extrapolation can be used in practice to address variability and uncertainty. There is a disproportionate focus on the sources of variability and uncertainty in human data, with relatively little consideration of how variation and uncertainty due to animal tests can be addressed. Furthermore, it is clear that, until the advantages and limitations of all toxicological methods are fully appraised and testing strategies and guidelines are agreed, the scope for improving the existing approaches to risk assessment will be severely limited. Hence, the use of alternative methods for hazard identification and characterisation merit more consideration than they were given in the draft report.

Animals↗
PubMed2005

The first de novo-designed antagonists of the human NK(2) receptor.

The de novo molecular design program SPROUT has been used in conjunction with a molecular model to produce a molecular template for a new class of NK(2) receptor antagonist. An efficient, stereocontrolled synthesis of a small series of molecules, designed to test the validity of this template, was developed. Competition assays using recombinant human NK(2) receptor support the structural requirements of this new designed molecular template.

Binding Sites↗
PubMed2005

Toxicity testing: creating a revolution based on new technologies.

Biotechnology is evolving at a tremendous rate. Although drug discovery is now heavily focused on high throughput and miniaturized screening, the application of these advances to the toxicological assessment of chemicals and chemical products has been slow. Nevertheless, the impending surge in demands for the regulatory toxicity testing of chemicals provides the impetus for the incorporation of novel methodologies into hazard identification and risk assessment. Here, we review the current and likely future value of these new technologies in relation to toxicological evaluation and the protection of human health.

Animal Testing Alternatives↗
PubMed2005

The fourth EC report on the statistics of laboratory animal use: trends, recommendations and future prospects.

At the beginning of 2005, the European Commission published its fourth report on the statistics of the number of animals used for experimental and other scientific purposes. A total of 10.7 million animals were used within the Member States of the European Union (EU) in 2002, an increase of almost a million animals since the 1999 report. France, Germany and the UK continue to be the largest users of animals for scientific purposes, and mice, rats, fish and birds remain the most commonly-used animals. For the first time, all 15 Member States used the standardised EU tables, as had been agreed in 1998. This has made it easier to identify areas on which Three Rs initiatives should be focused. Nevertheless, the reporting system still has a number of serious deficiencies. In particular, there are insufficient data on the numbers of animals that are kept or bred for research purposes, the numbers of transgenic animals, and the severity of procedures that are applied.

Animal Testing Alternatives↗
PubMed2005

The use of non-human primates in biological and medical research: evidence submitted by FRAME to the Academy of Medical Sciences/Medical Research Council/Royal Society/Wellcome Trust Working Group.

The Academy of Medical Sciences, the Medical Research Council, the Royal Society and the Wellcome Trust are undertaking a study into the use of non-human primates in biological and medical research. An independent working group of scientific experts, led by Sir David Weatherall, aims to produce a report summarising the findings of this study, early in 2006. The trends in primate research, and the nature and effects of recent and proposed changes in the global use of non-human primates in research, will be investigated. The associated ethical, welfare and regulatory issues, and the role and impact of the Three Rs principles of refinement, reduction and replacement will also be reviewed. As part of this study, a call for evidence was made. The evidence submitted by FRAME emphasised that the use of non-human primates for fundamental research or for regulatory testing still fails to take into account the fact that, although non-human primates are anatomically and physiologically similar to humans, they are not necessarily relevant models for studies on human disease or human physiology. FRAME continues to believe that we have a duty to ensure that these animals are not used without overwhelming evidence that they are the only suitable and relevant models for use in work of undeniable significance.

Acquired Immunodeficiency Syndrome↗
PubMed2005

The use of non-human primates in regulatory toxicology: comments submitted by FRAME to the Home Office.

The Home Office have circulated a document that summarises the discussions of a Primate Stakeholders Forum. The Forum took place in January 2004, and was convened to address the issues raised and the recommendations made in the Animal Procedures Committee 2002 report on the use of primates under the Animals (Scientific Procedures) Act 1986. The report emphasises the need for more resources focused on alternatives to toxicological testing in primates, including harmonising worldwide regulatory requirements, investigating the relevance of primate models, and improving the retrospective analysis of procedures involving primates. The document called for reasoned comments about the report to be submitted to the Home Office. In response, FRAME submitted a comprehensive paper, which evaluated each of the Animal Procedures Committees recommendations, along with the Home Office Forums comments. FRAME believes that, in coming to a decision as to whether primates should be used for regulatory testing, there must be full consideration of all the information available, including whether the ethological needs of any given species can be met prior to, during and following experimental use. Where these needs cannot be met, there must be a concerted effort to develop alternative models for research and testing. However, this should not detract from the ultimate goal of phasing out primate research altogether.

Animal Experimentation↗
PubMed2004

Evidence for the proximity of the extreme N-terminus of the neurokinin-2 (NK2) tachykinin receptor to Cys167 in the putative fourth transmembrane helix.

Neurokinin-2 receptor (NK(2)R) binding of [(3)H]-SR48968, a piperidinyl antagonist, is inhibited by methanethiosulfonate ethylammonium (MTSEA) in a time- and concentration-dependent manner. By the systematic alanine replacement of putative loop and transmembrane region cysteine residues (Cys(4), Cys(81), Cys(167), Cys(262), Cys(281), Cys(308), and Cys(309)), we have determined that MTSEA perturbs [(3)H]-SR48968 binding by modifying Cys(167) in transmembrane helix 4. Data were substantiated using glycine, serine, and threonine substitutions of Cys(167). MTSEA preferentially modifies cysteine residues that are in proximity to a negatively charged environment. Hence, aspartate and glutamate residues were systematically substituted with leucine or valine, respectively, and the inhibitory effects of MTSEA on [(3)H]-SR48968 binding were reevaluated to determine those acidic residues close to the MTSEA binding crevice. Most significantly, substitution of Asp(5) in the receptor's extreme N-terminus abolished the effects of MTSEA on [(3)H]-SR48968 binding. Therefore, our data would suggest close association of the extreme N-terminus with the extracellular surfaces of helices 4 and 3 in the NK(2)R in forming a binding crevice for MTSEA. The inhibition of SR48968 binding appears to result from loss of the SR48968 binding conformation of Gln(166) induced by MTSEA when it is coupled to Cys(167). Hence, it is proposed that there is mutually exclusive hydrogen bonding of SR48968 and MTSEA to Gln(166).

Amino Acid Sequence↗
PubMed2004

Scientific procedures on living animals in Great Britain in 2003: the facts, figures and consequences.

The statistics for animal procedures performed in 2003 were recently released by the Home Office. They indicate that, for the second year running, there was a significant increase in the number of laboratory animal procedures undertaken in Great Britain. The species and genera used, the numbers of toxicology and non-toxicology procedures, and the overall trends, are described. The implications of these latest statistics are discussed with reference to key areas of interest and to the impact of existing regulations and pending legislative reforms.

Animal Experimentation↗