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OBJECTIVE: A mixed-methods study exploring the UK general public's views towards consent for the use of biosamples for biomedical research. SETTING: Cross-sectional population-based focus groups followed by an online survey. PARTICIPANTS: 12 focus groups (81 participants) selectively sampled to reflect a range of demographic groups; 1110 survey responders recruited through a stratified sampling method with quotas set on sex, age, geographical location, socioeconomic group and ethnicity. MAIN OUTCOME MEASURES: (1) Views on the importance of consent when donating residual biosamples for medical research; (2) preferences for opt-in or opt-out consent approaches and (3) preferences for different consent models. RESULTS: Participants believed obtaining consent for use of residual biosamples was important as it was 'morally correct' to ask, and enabled people to make an active choice and retain control over their biosamples. Survey responders preferred opt-in consent (55%); the strongest predictor was being from a low socioeconomic group (OR 2.22, 95% CI 1.41 to 3.57, p=0.001) and having a religious affiliation (OR 1.36, 95% CI 1.01 to 1.81, p=0.04). Focus group participants had a slight preference for opt-out consent because by using this approach more biosamples would be available and facilitate research. Concerning preferred models of consent for research use of biosamples, survey responders preferred specific consent with recontact for each study for which their biosamples are eligible. Focus group participants preferred generic consent as it provided 'flexibility for researchers' and reduced the likelihood that biosamples would be wasted. The strongest predictor for preferring specific consent was preferring opt-in consent (OR 4.58, 95% CI 3.30 to 6.35, p=0.015) followed by non-'White' ethnicity (OR 2.94, 95% CI 1.23 to 7.14, p<0.001). CONCLUSIONS: There is a preference among the UK public for ongoing choice and control over donated biosamples; however, increased knowledge and opportunity for discussion is associated with acceptance of less restrictive consent models for some people.
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OBJECTIVE: A mixed methods study exploring the UK general public's willingness to donate human biosamples (HBSs) for biomedical research. SETTING: Cross-sectional focus groups followed by an online survey. PARTICIPANTS: Twelve focus groups (81 participants) selectively sampled to reflect a range of demographic groups; 1110 survey responders recruited through a stratified sampling method with quotas set on sex, age, geographical location, socioeconomic group and ethnicity. MAIN OUTCOME MEASURES: (1) Identify participants' willingness to donate HBSs for biomedical research, (2) explore acceptability towards donating different types of HBSs in various settings and (3) explore preferences regarding use and access to HBSs. RESULTS: 87% of survey participants thought donation of HBSs was important and 75% wanted to be asked to donate in general. Responders who self-reported having some or good knowledge of the medical research process were significantly more likely to want to donate (p<0.001). Reasons why focus group participants saw donation as important included: it was a good way of reciprocating for the medical treatment received; it was an important way of developing drugs and treatments; residual tissue would otherwise go to waste and they or their family members might benefit. The most controversial types of HBSs to donate included: brain post mortem (29% would donate), eyes post mortem (35%), embryos (44%), spare eggs (48%) and sperm (58%). Regarding the use of samples, there were concerns over animal research (34%), research conducted outside the UK (35%), and research conducted by pharmaceutical companies (56%), although education and discussion were found to alleviate such concerns. CONCLUSIONS: There is a high level of public support and willingness to donate HBSs for biomedical research. Underlying concerns exist regarding the use of certain types of HBSs and conditions under which they are used. Improved education and more controlled forms of consent for sensitive samples may mitigate such concerns.
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INTRODUCTION: Unacceptable failure rates in clinical trials are largely responsible for the high costs of bringing successful drugs to market - costs that are passed on to patients, insurers or healthcare providers. Furthermore, failures in clinical trials deny patients much-needed new drugs and potentially expose them to unnecessary risk. With so many medicines reaching their patent expiry date, pressure is on the pharmaceutical industry to not only increase its output of effective medicines but also improve its ability to minimise safety issues. AREAS COVERED: This review focuses on the availability and use of human tissues and their derivatives to explore potential toxicity problems of new drugs. The growth in the number and quality of human material-based assays and enabling technologies is reviewed, followed by a discussion of the application of such assays to identify specific toxicities, using specific examples. EXPERT OPINION: Although human tissues are now beginning to be seen as playing an important role in evaluating the potential for toxicity of new drugs in the clinic, their importance deserves to be more widely recognised and their use in the identification of toxicity issues as early as possible in the drug development life cycle should be significantly increased.
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Evaluación Preclínica de Medicamentos/métodos , Pruebas de Toxicidad/métodos , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , HumanosRESUMEN
Human tissues are invaluable resources for pharmaceutical research. They provide information about disease pathophysiology--and equally importantly, healthy function; confirmation (or refutation) of potential drug targets; validation (or otherwise) of other models employed; and functional models for assessing drugs' effects, whether beneficial or undesirable, in the most appropriate environment that can be replicated outside the human body. While human tissues have long been prized by pathologists in furthering our understanding of disease processes, there is a growing appreciation of their value at the late pre-clinical stage of drug discovery. Human tissues' potential to contribute to earlier phases of the process, before significant resources have been expended, is also now gaining recognition. Mounting concern over high rates of clinical stage drug failures mandates exploration of avenues for improving efficiency. Human tissue-based assays could play a key role in improving the translation process, as well as in moving towards stratified or personalised medicines. This editorial highlights some of the potential benefits of introducing human biosamples at each stage of the research process as a drug moves from concept to clinic. Some of the challenges with respect to obtaining tissues, minimising variability and gaining acceptance are also discussed.
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Descubrimiento de Drogas/métodos , Análisis de Matrices Tisulares , Animales , Biomarcadores , Aprobación de Drogas/economía , Descubrimiento de Drogas/economía , Humanos , Células Madre Pluripotentes Inducidas/fisiología , Especificidad de Órganos , Investigación Biomédica Traslacional/métodosRESUMEN
On 20 October 2009, scientists and politicians gathered in the House of Lord to discuss the barriers medical researchers face when attempting to access surplus human tissues. Presently, such tissues, including those surplus to requirements for diagnosis after surgery, are all too often incinerated because patients' permission has not been sought for them to be used in medical research. A similar situation arises where organs which have been donated for transplant are unsuitable for donation. As a consequence of the conference, the Human Tissues Working Party was established to enable the discussions which began so fruitfully at the conference to continue, and to allow delegates, and participants who have joined subsequently, to present a unified case in submissions to public consultations, for example.
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Congresos como Asunto , Especificidad de Órganos , Humanos , Bancos de TejidosRESUMEN
The challenges to using human tissues in research are many and varied. However, there is little consensus on how concerns raised by researchers should be addressed, and who should be responsible for ensuring that patients continue to benefit from medical research carried out using human tissues which have been ethically donated or collected after surgery, or where organs donated for transplant are unsuitable for this purpose. A conference in the House of Lords sought to bring together stakeholders from all areas of human tissue research to discuss the problems experienced, share solutions, and form a Working Party to carry the conference momentum forward into action in the near future.
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Investigación Biomédica , Bancos de Tejidos , Humanos , Bancos de Tejidos/economía , Obtención de Tejidos y Órganos , Investigación Biomédica Traslacional , Reino UnidoAsunto(s)
Descubrimiento de Drogas , Industria Farmacéutica , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Alternativas a las Pruebas en Animales , Animales , Animales de Laboratorio , Humanos , Londres , Retirada de Medicamento por Seguridad , Factores de Tiempo , Pruebas de Toxicidad , Insuficiencia del TratamientoRESUMEN
BACKGROUND: Dictyostelium discoideum amoebae are haploid and, as they share many features with animal cells, should be an ideal creature for studying basic processes such as cell locomotion. Isolation of mutants in this amoeba has largely been limited to non-essential genes: nsfA-the gene for NEM-sensitive factor-remains the only essential gene for which conditional (ts) mutants exist. These ts mutants were generated by gene replacement using a library of mutagenised nsfA containing a selectable marker: transformants were then screened for temperature sensitivity. The success of this approach depended on the high level of homologous recombination prevailing at this locus: approximately 95% of selected clones were homologous recombinants. This is unusually high for Dictyostelium: homologous recombination at other loci is usually much less, usually between 0-30%, making the isolation of ts mutants much more tedious. METHODOLOGY/PRINCIPAL FINDINGS: In trying to make ts mutants in sec1A, homologous recombination was found to be only approximately 25%. A new approach, involving single loxP sites, was investigated. LoxP sites are 34 bp sequences recognised by Cre recombinase and between which this enzyme catalyses recombination. A Dictyostelium line containing a single loxP site adjacent to the 3' end of the sec1A gene was engineered. A sec1A replacement DNA also containing a single loxP site in a homologous position was then introduced into this cell line. In the presence of CRE recombinase, homologous recombination increased to approximately 80% at this locus, presumably largely driven by intermolecular recombination between the two single loxP sites. CONCLUSIONS/SIGNIFICANCE: A route to increase the rate of homologous recombination at a specific locus, sec1A, is described which enabled the isolation of 30 ts mutants in sec1A. One of these, sec1Ats1,has been studied and found to cease moving at the restrictive temperature. The approach described here may be valuable for enhancing homologous recombination at specified loci and thus for introducing mutations into specific genes in Dictyostelium and other creatures.
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Dictyostelium/genética , Proteínas Munc18/genética , Mutación , Proteínas Protozoarias/genética , Recombinación Genética , Animales , Movimiento Celular/fisiología , ADN Protozoario , Integrasas/genética , Integrasas/metabolismo , Proteínas Munc18/metabolismo , Proteínas Protozoarias/metabolismoRESUMEN
BACKGROUND: Cycloheximide is a protein synthesis inhibitor that acts specifically on the 60S subunit of eukaryotic ribosomes. It has previously been shown that a short incubation of Dictyostelium discoideum amoebae in cycloheximide eliminates fluid phase endocytosis. RESULTS: We found that treatment with cycloheximide also causes the amoebae to retract their pseudopodia, round up and cease movement. Furthermore, fluid phase endocytosis, phagocytosis and capping cease in the presence of 2 mM cycloheximide, although membrane uptake, as measured using FM1-43, is unaffected. In the presence of cycloheximide, aggregation-competent amoebae sensitive to cAMP, although round, can still localise CRAC, ABP120, PI3K and actin polymerisation in response to a micropipette filled with cAMP. The behaviour of wild-type amoebae in the presence of cycloheximide is surprisingly similar to that of amoebae having a temperature-sensitive version of NSF at the restrictive temperature. CONCLUSION: Our results may suggest that, upon cycloheximide treatment, either a labile protein required for polarised membrane recycling is lost, or a control mechanism linking protein synthesis to membrane recycling is activated.
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Movimiento Celular/efectos de los fármacos , Polaridad Celular/efectos de los fármacos , Cicloheximida/farmacología , Dictyostelium/citología , Dictyostelium/efectos de los fármacos , Actinas/metabolismo , Animales , Transporte Biológico , Biopolímeros/metabolismo , Membrana Celular/metabolismo , Fagocitosis/efectos de los fármacos , Biosíntesis de Proteínas , Factores de TiempoRESUMEN
The objective of this study was the pharmaco-toxicological understanding of the constituents of an authenticated herbal mixture. The mixture was prepared by maceration in ethanol and subsequent dilution to produce a topically applied lotion, for which the intended target conditions are psoriasis and eczema. A three-tiered in vitro screening strategy was adopted for evaluating this product, comprising cytotoxicity assays; mutagenicity screening and therapeutic evaluation. Viability assays performed with dilutions of both the herbal concentrate and final product on organotypic cell lines indicated that neither preparation acted as an irritant. Genotoxicity screening using six strains of Salmonella typhimurium showed no mutagenic potential, and furthermore significant anti-microbial activity was evident. Therapeutic evaluation involved assessing the antioxidant potential of the extract, which can be correlated to an anti-inflammatory effect. Nitroblue-tetrazolium (NBT) assay results indicate that the extract can reduce superoxide anion generation by 45%. The extract also increased cell viability on exposure to hydrogen peroxide by 28%, illustrating its dismutation potential. A 3-D skin culture system, EpiDerm, released 3000 microg/ml upon exposure to the extract, implying that the components enhance arachidonic acid metabolism. Overall, it may be concluded that the herbal extract is sufficiently non-toxic for dermal application and possesses anti-inflammatory activity.