212 research outputs found
Scientific Evidence and the Law: An Objective Bayesian Formalisation of the Precautionary Principle in Pharmaceutical Regulation
No full textThe paper considers the legal tools that have been developed in German pharmaceutical regulation as a result of the precautionary attitude inaugurated by the Contergan decision (1970). These tools are (i) the notion of "well-founded suspicion", which attenuates the requirements for safety intervention by relaxing the requirement of a proved causal connection between danger and source, and the introduction of (ii) the reversal of proof burden in liability norms. The paper focuses on the first and proposes seeing the precautionary principle as an instance of the requirement that one should maximise expected utility. In order to maximise expected utility certain probabilities are required and it is argued that objective Bayesianism offers the most plausible means to determine the optimal decision in cases where evidence supports diverging choices
Safety vs. efficacy assessment of pharmaceuticals: Epistemological rationales and methods
No full textAbstractIn their comparative analysis of Randomised Clinical Trials and observational studies, Papanikoloau et al. (2006) assert that “it may be unfair to invoke bias and confounding to discredit observational studies as a source of evidence on harms”. There are two kinds of answers to the question why this is so. One is based on metaphysical assumptions, such as the problem of causal sufficiency, modularity and other statistical assumptions. The other is epistemological and relates to foundational issues and how they determine the constraints we put on evidence. I will address here the latter dimension and present recent proposals to amend evidence hierarchies for the purpose of safety assessment of pharmaceuticals; I then relate these suggestions to a case study: the recent debate on the causal association between paracetamol and asthma. The upshot of this analysis is that different epistemologies impose different constraints on the methods we adopt to collect and evaluate evidence; thus they grant “lower level” evidence on distinct grounds and at different conditions. Appreciating this state of affairs illuminates the debate on the epistemic asymmetry concerning benefits and harms and sets the basis for a foundational, as opposed to heuristic, justification of safety assessment based on heterogeneous evidence
A INFORMAÇÃO GENÉTICA É DE PROPRIEDADE FAMILIAR? AMPLIANDO O ARGUMENTO DA QUEBRA DA CONFIDENCIALIDADE E O DEVER DE INFORMAR PESSOAS EM SITUAÇÃO DE RISCO
No full textA current trend in bioethics considers genetic information as family property. This paper uses a logical approach to critically examine Matthew Liao’s proposal on the familial nature of genetic information as grounds for the duty to share it with relatives and for breach of confidentiality by the geneticist. The authors expand on the topic by examining the relationship between the arguments of probability and the familial nature of genetic information, as well as the concept of harm in the context of genetic risk. Lastly, they examine the concept of harm in relation to the type of situations w the potential recipient of the information is not the person directly affected by the risk.Considerar la información genética como una propiedad familiar es una tendencia actual en Bioética. El artículo examina con un método crítico, desde un enfoque lógico conceptual la propuesta de Matthew Liao, que sugiere como justificación de la obligación de compartir información entre familiares y para la ruptura de la confidencialidad, la naturaleza familiar de la información genética. Se amplía el tema mediante la relación entre los argumentos de la probabilidad y naturaleza familiar de la información genética y analiza el concepto de daño en el contexto del riesgo genético. Por último examina del concepto de daño en relación con el tipo de situaciones en que el posible receptor de la información no es la persona directamente afectada por el riesgo.Considerar a informação genética como uma propriedade familiar é uma tendência atual em Bioética. O artigo examina com um método crítico, a partir de um enfoque lógico conceitual, a proposta de Matthew Liao, que sugere como justificativa a obrigação de compartilhar informação entre familiares e para a quebra da confidencialidade, a natureza familiar da informação genética. Amplia-se o tema mediante a relação entre os argumentos da probabilidade e a natureza familiar da informação genética, e analisa o conceito de dano no contexto do risco genético. Por último, examina o conceito de dano referente ao tipo de situações no qual o possível receptor da informação não é a pessoa diretamente afetada pelo risco
Estrategias para reducir Listeria monocytogenes en carne y productos cárnicos
No full textListeria monocytogenes es una bacteria patógena causante de listeriosis y que habitualmente se encuentra en carne y productos cárnicos como los salames. La producción de carne fresca y de salame tienen características propias y por tanto las estrategias usadas para controlar la carga microbiana difieren en cada proceso. El objetivo general de esta tesis fue estudiar el comportamiento de Listeria monocytogenes en carne envasada al vacío expuesta a radiación UV-C y ácido láctico y en salames en distintas condiciones de proceso para obtener en cada matriz las condiciones óptimas que logren la máxima reducción de Listeria monocytogenes en el producto final. Como resultado de esta tesis se aislaron e identificaron 35 cepas de Listeria: 29 L. innocua y 6 L. monocytogenes pertenecientes a dos serotipos (4b y 1/2a). Mediante la electroforesis de campos pulsados (PFGE) se distinguieron dos pulsotipos diferentes de L. monocytogenes (pulsotipo 1 para los aislados de serotipo 4b y pulsotipo 2 para los aislados de serotipo 1/2a). Todos los aislamientos presentaron sensibilidad al ácido láctico in vitro. La concentración mínima inhibitoria en TSB-YE fue de 0.3 % y la concentración mínima bactericida de 0.7 %. Los aislamientos de L. monocytogenes encontrados fueron sensibles al UV-C in vitro, siendo la DL50 de 3.47 mJ/cm2 para L100A1 y 5.39 mJ/cm2 para L101E3, siendo esta diferencia no significativa (p < 0.05). Se seleccionó la cepa L100A1 para realizar los estudios en carne. Mediante la metodología de superficie de respuesta se obtuvo un modelo cuadrático que predice la reducción logarítmica de L. monocytogenes en carne vacuna envasada al vacío tratada con ácido láctico y UV-C. La reducción logarítmica máxima para L. monocytogenes fue de 1.55 ± 0.41 log ufc/g y para bacterias ácido lácticas de 1.55 ± 1.15 log ufc/g, con un impacto mínimo en el color de la carne aplicando 2.6 % de ácido láctico y 330 mJ/cm2 UV-C.Estas condiciones afectaron el crecimiento de L. monocytogenes y retrasaron el crecimiento de las bacterias ácido lácticas por 2 semanas en muestras de carne envasadas al vacío a 4 ºC. Esta estrategia podría contribuir para mejorar la seguridad y la vida útil de la carne vacuna envasada al vacío con un bajo impacto en el color de la carne. En cuanto al trabajo en salames, se estudió a escala piloto el efecto sobre la sobrevivencia de L. monocytogenes, que tienen la temperatura de fermentación, la temperatura de secado, el diámetro del producto y el lactato de sodio inoculando la masa con Listeria innocua como microorganismo modelo. El comportamiento de Listeria se modeló según la ecuación de Baranyi & Roberts obteniéndose para cada condición de ensayo el parámetro μ (tasa de inactivación de L. innocua), el valor inicial de L. innocua (Yo), el valor final alcanzado (YEND) y se calculó la variación en los recuentos de Listeria innocua entre el tiempo inicial y el tiempo final del proceso (Yo - YEND). Se determinó que el agregado de lactato de sodio al 2 % durante la fermentación compromete la reducción de L. innocua. Del estudio de las condiciones de proceso en la sobrevivencia de L. innocua se obtuvieron dos modelos matemáticos, un modelo cuadrático para la tasa de inactivación de Listeria (μ) y un modelo 2F para la reducción total de Listeria alcanzada (Yo - YEND) que permiten explicar estas respuestas en función de las temperaturas de fermentación y secado y del calibre del salame. Los valores máximos de μ y de (Yo - YEND) se obtienen cuando la temperatura de fermentación es 30 ºC y la de secado de 20 ºC. Si bien la reducción total de Listeria alcanzada al final del proceso, en ausencia de lactato, alcanzó siempre valores de 3 log ufc/g, existieron condiciones que permitieron el crecimiento de Listeria durante el secado y que en caso de partir de carne con recuentos de Listeria mayores a 3 log ufc/g no se obtendríaSi bien la reducción total de Listeria alcanzada al final del proceso, en ausencia de lactato, alcanzó siempre valores de 3 log ufc/g, existieron condiciones que permitieron el crecimiento de Listeria durante el secado y que en caso de partir de carne con recuentos de Listeria mayores a 3 log ufc/g no se obtendría un producto final que cumpla con la legislación nacional de ausencia de Listeria en 25 gramos
Rapid disease progression in HIV-1 perinatally infected children born to mothers receiving zidovudine monotherapy during pregnancy. The Italian register for HIV Infection in Children
No full textDevelopment of quantitative real-time PCR and digital droplet-PCR assays for rapid and early detection of the spoilage yeasts Saccharomycopsis fibuligera and Wickerhamomyces anomalus in bread
No full textIn the present study, for the first time, high sensitive quantitative polymerase chain reaction (qPCR) and digital droplet polymerase chain reaction (ddPCR) assays were developed to detect and quantify total eumycetes with potential application in several food matrices and to specifically determine the level of contamination by Saccharomycopsis fibuligera and Wickerhamomyces anomalus cells directly in bread. Among the candidate target genes used to develop the assays, car1 gene was chosen to detect the two spoilage yeasts S. fibuligera and W. anomalus. The specificity of the PCR assays was tested using purified genomic DNA from 36 bacterial and fungal strains. The sensitivity of the assays was defined by using tenfold serial dilutions of genomic DNA starting from 106 cfu/mL to 1 cfu/mL of S. fibuligera and W. anomalus. Validation of the assays was achieved by enumeration of S. fibuligera and W. anomalus DNA copies from samples of artificially contaminated bread homogenates detecting up to 10 cfu/mL (0.06 ± 0.01 copies/μL) of W. anomalus by using ddPCR. In conclusion, the developed qPCR and ddPCR assays demonstrate strong performance in the early detection of S. fibuligera and W. anomalus in bread, representing promising tools for applying high-throughput approaches to regularly monitor bread quality
Increasing number of pregnancies at risk for congenital syphilis in the new millennium in Northern-Central Italy
No full textObjectives. The recent spread of syphilis to fertile women in some European countries has led to an increased risk of congenital syphilis (CS). We tried to outline the extent of this problem in Northern-Central Italy, the risk factors for mother/child infection, the appropriateness of case management, and the features of infected children. Methods. This descriptive case series includes all mother-child pairs at risk for CS, identified between Jan. 1st 2000 and Dec. 31st 2003 in four Italian cities. Information was collected by registration and follow-up forms. Children were followed until their infection status was defined. Results. Forty-seven mother-child pairs were identified with increasing frequency over the study period; 10 (21.3%) women were Italian, 37 foreigners. Fourteen (31.8%) women had other Sexually transmitted diseases (STDs). There was a high prevalence of intrauterine growth delay (8.7%) and stillbirths (9.1%). Only 26 women were tested within the 16th week of gestation. Nineteen women (40.4%) were at high risk of transmission; among their children, 10 (52.6%) received specific treatment. Infection status was defined in 37 children, and 4 out of 15 (26.7%) born to women at high risk of transmission were infected. Conclusion. Our results suggest that the number of at-risk pregnancy for CS is increasing in Northern-Central Italy, mostly following immigration, and universal prenatal screening for syphilis should be restored. The mother-child management was often not in line with the current guidelines, presumably because obstetricians and pediatricians have lost specific knowledge of this infection
Ciclo evolutivo do Hepatozoon triatomae (Sporozoa, Haemogregarinidae) parasita de triatomíneos Evolution cycle of the Hepatozoon triatomae (Sporozoa, Haemogregarinidae), parasite of triatominea
No full textRelata-se o encontro no Estado de São Paulo, Brasil, de triatomíneos e lagartos, respectivamente o Triatoma arthurneivai e Tropidurus torquatus, parasitados por uma hemogregarina semelhante a Hepatozoon triatomae (Osimani, 1942) Reichenow, 1953. São apresentados aspectos da sua morfologia e estudadas as diversas fases do seu ciclo evolutivo, este inteiramente reproduzido em laboratório.The author relates the discovery of Triatoma arthurneivai and Tropidurus torquatus, in the localities of Lavras de Cima and Santo Antonio, State of São Paulo, Brazil, infected by a hemogregarine similar to Hepatozoon triatomae (Osimani, 1942) Reichenow 1953. He presents certain aspects of its morphology and also studies the several phases of its evolution cycle, which were completed in the laboratory
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