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1.
Altern Lab Anim ; 34 Suppl 1: 41-68, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16555959

RESUMO

In February 2001, the European Commission published a White Paper proposing that a single new system of chemical regulation should be applied throughout the Member States of the European Union. The proposed Registration, Evaluation and Authorisation of Chemicals (REACH) system was to include both new and existing chemicals, with the aim of ensuring that sufficient pertinent data were made available to enable human health and the environment to be protected. The policy was founded on the principle of sustainable industrial development, and ambitiously attempted to incorporate the needs and views of key stakeholder organisations, such as industry, trade associations, consumer groups, environmentalists, animal welfarists and Member State governments. During the period between the publication of the White Paper and the on-line publication of consultation documents, as part of a public consultation exercise, in May 2003, many of these key stakeholder organisations produced material in support of or critical of the White Paper, either in part or as a whole. In this paper, we have attempted to review this extensive material and to present it in the context of the current chemical regulatory system that the REACH system will replace. Emphasis is placed on the impact of the new policy on the number of animals used in the testing regimes within the REACH system and the inclusion of alternative methods into the legislation. Although supportive of the overriding aims of the new policy, FRAME believes that the fundamental concept of a risk-free environment is flawed, and that the new REACH system will involve the unjustifiable use of millions of laboratory animals. The new policy does include alternative methods, particularly for base set substances. Nevertheless, alternative testing methods that are already available have been excluded and replaced with outdated in vivo versions. There is also insufficient detail with regard to the further development and validation of alternative methods, particularly for substances of high concern, such as endocrine disrupters or reproductive toxins, for which no alternative testing methods currently exist.

2.
Altern Lab Anim ; 34 Suppl 1: 29-40, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16555958

RESUMO

In May, 2003, the European Commission published detailed proposals relating to its 2001 White Paper--Strategy for a Future Chemicals Policy. The White Paper described a new registration system called the REACH (Registration, Evaluation and Authorisation of Chemicals) system, for both new and existing chemicals. Subsequently, these detailed proposals were available for an eight-week consultation period for stakeholders to voice their views and concerns. In this paper, we describe our reactions to the Commissions more-detailed proposals. These include the creation of a European Chemicals Agency to implement the REACH system in conjunction with Competent Authorities (CAs) in Member States and the Commission itself. Unfortunately, many of our concerns and suggestions, previously voiced and shared with several other key stakeholders, remain unanswered, but are as relevant as when the White Paper was published. In particular, we are concerned about the lack of a clear and coherent strategy. There is no guidance for registrants on intelligent testing to maximise the use of non-animal approaches to safety testing, based on a combination of factors for estimating exposure levels, rather than mainly on production volumes. We are also concerned about the absence of a clear programme for the development, improvement and validation of new alternative methods, in conjunction with the Commissions own unit, the European Centre for the Validation of Alternative Methods, as well as other organisations with relevant expertise and experience, including FRAME. Finally, we explain why such measures should be introduced, together with clearer guidelines for the respective roles of the Agency, the CAs and the Commission in implementing and harmonising the REACH system at the European Union and Member State levels. A series of recommendations are made, to improve the situation and to improve the risk assessment process.

3.
Altern Lab Anim ; 34 Suppl 1: 69-75, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16555960

RESUMO

This document discusses recommendations made by FRAME and the Royal Commission on Environmental Pollution (RCEP) with regard to the current European Commission proposals on the Registration, Evaluation and Authorisation of Chemicals (REACH) system for assessing the risks of chemicals to humans, wildlife and the environment. Of several common aims and recommendations, the two most important are: a) the greater use of non-animal testing methods, especially computational prediction methods (for example, [quantitative] structure-activity relationships, expert systems and biokinetic modelling) for prioritising chemicals for hazard assessment; and b) the greater use of intelligent exposure-based targeted risk assessment, with less emphasis being placed on tonnage-triggers. FRAME has produced a decision-tree testing scheme to illustrate the way in which these approaches could be used, together with in vitro test methods. This scheme has been slightly modified to take account of proposals subsequently made by the RCEP. In addition, FRAME points out that new and improved computational methods are needed through more coordinated research, and that these and existing methods need to be validated. The similarities between the independent publications of FRAME and the RCEP add weight to the recommendations that each have made concerning the implementation of the REACH system.

4.
Hypertension ; 43(6): 1290-6, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15078864

RESUMO

An adverse environment around conception and implantation influences later fetal growth and development to term in humans and sheep. Indeed, preimplantation undernutrition of rats elevated the systolic blood pressure of the resultant adult offspring. In this study, adult cardiovascular function is examined in a slower growing, non-litter-bearing species after peri-implantation undernutrition. Eight ewes were fed to 50% equivalent food intake of 12 control ewes from 1 to 30 days (term approximately 147 days) only. Following consumption of an adequate diet to term, natural lambing, and then weaning, resting cardiovascular status and baroreflex function were examined in the resultant young adult offspring. Birth weight and postnatal growth to 1 year of age were unaffected by early undernutrition; however, nutrient-restricted sheep had increased pulse pressure, a reduced rate pressure product, and a leftward shift in their baroreflex function curve. Baroreflex sensitivity during angiotensin II infusion was also blunted in early nutrient-restricted sheep but the tachycardia following a reduction in central blood pressure appeared potentiated, relative to controls. The data suggest that peri-implantation undernutrition may program long-term cardiovascular dysfunction that ultimately increases the risk of hypertension later in life. An increase in regional angiotensin II activity during this critical early phase of development is a likely candidate mechanism for the effects observed. The data have broad implications for the health outcome of those offspring from mothers who were poorly nourished during early, often unknown pregnancy and for embryos artificially manipulated because of infertility treatment.


Assuntos
Angiotensina II/farmacologia , Barorreflexo/efeitos dos fármacos , Blastocisto , Hipertensão/etiologia , Desnutrição/fisiopatologia , Complicações na Gravidez/fisiopatologia , Efeitos Tardios da Exposição Pré-Natal , Reflexo Anormal/efeitos dos fármacos , Animais , Peso ao Nascer , Pressão Sanguínea , Feminino , Privação de Alimentos , Hemodinâmica/efeitos dos fármacos , Hipotensão/complicações , Nitroprussiato/farmacologia , Tamanho do Órgão , Fenilefrina/farmacologia , Gravidez , Ovinos , Taquicardia/etiologia , Vasodilatadores/farmacologia
5.
Pediatr Res ; 53(2): 302-8, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12538790

RESUMO

The present study examined the extent to which abundance of the prolactin receptor (PRLR) and a range of primary mitochondrial proteins are influenced by either maternal nutrition and/or fetal number in adipose tissue. Pregnant sheep were control fed [consuming 100% of total metabolizable energy (ME) requirements (taking into account requirements for both ewe maintenance and growth of the conceptus to produce a 4.5-kg lamb at term) for that stage of gestation] or were nutrient restricted (consuming 60% of total ME requirements). All ewes lambed normally at term and both perirenal adipose and hepatic tissues were sampled within 6 h of birth. Plasma membranes and mitochondria were prepared and analyzed using immunoblotting for abundance of PRLR and/or cytochrome c, voltage-dependent anion channel (VDAC), and uncoupling protein-1 (UCP1). Irrespective of maternal nutrition, abundance of specific isoforms of PRLR were significantly higher in adipose tissue sampled from twins compared with singletons and total UCP1 concentration per milligram of tissue was increased (p < 0.05). There was no effect of fetal number on PRLR abundance in the liver. Maternal nutrient restriction resulted in an increased abundance of both cytochrome c (p < 0.001) and VDAC in adipose tissue of twins but not singletons. This occurred despite maternal nutrition having no effect on either lamb body or adipose tissue weights, although both were lower (p < 0.05) in twins compared with singletons. In conclusion, fetal adipose tissue development is highly sensitive to nutritionally mediated changes in late gestation. An increase in fetal number results in greater PRLR abundance, which, in conjunction with a decrease in maternal nutrition, results in up-regulation of specific mitochondrial proteins.


Assuntos
Tecido Adiposo/crescimento & desenvolvimento , Tecido Adiposo/metabolismo , Animais Recém-Nascidos/crescimento & desenvolvimento , Desenvolvimento Embrionário e Fetal/fisiologia , Fenômenos Fisiológicos da Nutrição Materna/fisiologia , Receptores da Prolactina/metabolismo , Animais , Peso ao Nascer/fisiologia , Feminino , Idade Gestacional , Proteínas Mitocondriais/metabolismo , Gravidez , Ovinos , Gemelaridade Monozigótica
6.
Altern Lab Anim ; 31(5): 501-28, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15598177

RESUMO

In February 2001, the European Commission published a White Paper proposing that a single new system of chemical regulation should be applied throughout the Member States of the European Union. The proposed Registration, Evaluation and Authorisation of Chemicals (REACH) system was to include both new and existing chemicals, with the aim of ensuring that sufficient pertinent data were made available to enable human health and the environment to be protected. The policy was founded on the principle of sustainable industrial development, and ambitiously attempted to incorporate the needs and views of key stakeholder organisations, such as industry, trade associations, consumer groups, environmentalists, animal welfarists and Member State governments. During the period between the publication of the White Paper and the on-line publication of consultation documents, as part of a public consultation exercise, in May 2003, many of these key stakeholder organisations produced material in support of or critical of the White Paper, either in part or as a whole. In this paper, we have attempted to review this extensive material and to present it in the context of the current chemical regulatory system that the REACH system will replace. Emphasis is placed on the impact of the new policy on the number of animals used in the testing regimes within the REACH system and the inclusion of alternative methods into the legislation. Although supportive of the overriding aims of the new policy, FRAME believes that the fundamental concept of a risk-free environment is flawed, and that the new REACH system will involve the unjustifiable use of millions of laboratory animals. The new policy does include alternative methods, particularly for base-set substances. Nevertheless, alternative testing methods that are already available have been excluded and replaced with outdated in vivo versions. There is also insufficient detail with regard to the further development and validation of alternative methods, particularly for substances of high concern, such as endocrine disrupters or reproductive toxins, for which no alternative testing methods currently exist.


Assuntos
Legislação de Medicamentos , Experimentação Animal/legislação & jurisprudência , Alternativas aos Testes com Animais/legislação & jurisprudência , Bem-Estar do Animal , Animais , Indústria Farmacêutica , Europa (Continente) , União Europeia , Governo , Humanos , Política Pública , Pesquisa , Testes de Toxicidade , Toxicologia , Reino Unido
7.
Altern Lab Anim ; 31(5): 529-35, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15598178

RESUMO

This document discusses recommendations made by FRAME and the Royal Commission on Environmental Pollution (RCEP) with regard to the current European Commission proposals on the Registration, Evaluation and Authorisation of Chemicals (REACH) system for assessing the risks of chemicals to humans, wildlife and the environment. Of several common aims and recommendations, the two most important are: a) the greater use of non-animal testing methods, especially computational prediction methods (for example, [quantitative] structure-activity relationships, expert systems and biokinetic modelling) for prioritising chemicals for hazard assessment; and b) the greater use of intelligent exposure-based targeted risk assessment, with less emphasis being placed on tonnage-triggers. FRAME has produced a decision-tree testing scheme to illustrate the way in which these approaches could be used, together with in vitro test methods. This scheme has been slightly modified to take account of proposals subsequently made by the RCEP. In addition, FRAME points out that new and improved computational methods are needed through more coordinated research, and that these and existing methods need to be validated. The similarities between the independent publications of FRAME and the RCEP add weight to the recommendations that each have made concerning the implementation of the REACH system.


Assuntos
Poluição Ambiental/legislação & jurisprudência , Legislação de Medicamentos , Testes de Toxicidade/métodos , Alternativas aos Testes com Animais , Animais , Biologia Computacional , União Europeia , Humanos , Relação Quantitativa Estrutura-Atividade , Medição de Risco
8.
Altern Lab Anim ; 31(3): 353-64, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-15612876

RESUMO

In May, 2003, the European Commission published detailed proposals relating to its 2001 White Paper - Strategy for a Future Chemicals Policy. The White Paper described a new registration system called the REACH (Registration, Evaluation and Authorisation of Chemicals) system, for both new and existing chemicals. Subsequently, these detailed proposals were available for an eight-week consultation period for stakeholders to voice their views and concerns. In this paper, we describe our reactions to the Commission's more-detailed proposals. These include the creation of a European Chemicals Agency to implement the REACH system in conjunction with Competent Authorities (CAs) in Member States and the Commission itself. Unfortunately, many of our concerns and suggestions, previously voiced and shared with several other key stakeholders, remain unanswered, but are as relevant as when the White Paper was published. In particular, we are concerned about the lack of a clear and coherent strategy. There is no guidance for registrants on intelligent testing to maximise the use of non-animal approaches to safety testing, based on a combination of factors for estimating exposure levels, rather than mainly on production volumes. We are also concerned about the absence of a clear programme for the development, improvement and validation of new alternative methods, in conjunction with the Commission's own unit, the European Centre for the Validation of Alternative Methods, as well as other organisations with relevant expertise and experience, including FRAME. Finally, we explain why such measures should be introduced, together with clearer guidelines for the respective roles of the Agency, the CAs and the Commission in implementing and harmonising the REACH system at the European Union and Member State levels. A series of recommendations are made, to improve the situation and to improve the risk assessment process.


Assuntos
Alternativas ao Uso de Animais/métodos , Química/legislação & jurisprudência , Política Pública , Medição de Risco/legislação & jurisprudência , Testes de Toxicidade/métodos , Alternativas ao Uso de Animais/legislação & jurisprudência , União Europeia , Guias como Assunto/normas
9.
Pediatr Res ; 52(1): 85-90, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12084852

RESUMO

The influence of route of delivery, ambient temperature, maternal dexamethasone treatment, and postnatal age on plasma concentrations of leptin or leptin mRNA abundance in perirenal adipose tissue was examined from 6-h-old lambs, born vaginally or delivered by cesarean section into warm (30 degrees C) or cool (15 degrees C) ambient temperatures, and from cesarean section-delivered lambs whose mothers had been treated with dexamethasone beginning 2 d before parturition. The ontogeny of leptin during the first month of postnatal life was also examined. In lambs born into a cool ambient temperature, but not in those born to dexamethasone-treated mothers, leptin mRNA abundance decreased within 6 h of birth. Plasma concentrations of leptin decreased during the first 6 h of life, an adaptation delayed by cesarean section birth. After the first day of postnatal life, both plasma concentrations of leptin and its mRNA increased to peak at 7 d of age and were positively correlated with each other, as well as with whole-body and perirenal adipose tissue weights. A similar relationship was not observed after 7 d of age, as plasma leptin declined despite an increase in adipose tissue weight. In conclusion, route of delivery, ambient temperature, or maternal dexamethasone therefore delays the rate of leptin disappearance after birth. Concomitantly, leptin abundance was only associated with body and adipose tissue weights for 1 week after birth, which may be coincident with the onset of peak lactation and the time at which nutrient supply should no longer be limiting to the neonate.


Assuntos
Dexametasona/farmacologia , Glucocorticoides/farmacologia , Leptina/sangue , Leptina/genética , Temperatura , Adaptação Fisiológica/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Cesárea , Feminino , Expressão Gênica/efeitos dos fármacos , Gravidez , Efeitos Tardios da Exposição Pré-Natal , RNA Mensageiro/análise , Ovinos
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