868 resultados para Human experimentation in medicine


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Purpose:The aim of this study was to determine whether mutations in mitochondrial DNA play a role in high-pressure primary open-angle glaucoma (OMIM 137760) by analyzing new data from massively parallel sequencing of mitochondrial DNA.
Methods:Glaucoma patients with high-tension primary open-angle glaucoma and ethnically matched and age-matched control subjects without glaucoma were recruited. The entire human mitochondrial genome was amplified in two overlapping fragments by long-range polymerase chain reaction and used as a template for massively parallel sequencing on an Ion Torrent Personal Genome Machine. All variants were confirmed by conventional Sanger sequencing.
Results:Whole-mitochondrial genome sequencing was performed in 32 patients with primary open-angle glaucoma from India (n = 16) and Ireland (n = 16). In 16 of the 32 patients with primary open-angle glaucoma (50% of cases), there were 22 mitochondrial DNA mutations consisting of 7 novel mutations and 8 previously reported disease-associated sequence variants. Eight of 22 (36.4%) of the mitochondrial DNA mutations were in complex I mitochondrial genes.
Conclusion:Massively parallel sequencing using the Ion Torrent Personal Genome Machine with confirmation by Sanger sequencing detected a pathogenic mitochondrial DNA mutation in 50% of the primary open-angle glaucoma cohort. Our findings support the emerging concept that mitochondrial dysfunction results in the development of glaucoma and, more specifically, that complex I defects play a significant role in primary open-angle glaucoma pathogenesis.

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The European Court of Human Rights has begun to refer to the EU Charter of Fundamental Rights in order to support its reasoning for interpreting the European Convention on Human Rights in a particular way. But the EU Charter does not yet have any special status in that regard, being treated by the Court as on a par with numerous other documents of international law. The Court’s use of the Charter began in connection with arts 8 and 12 of the Convention (the right to a family life and the right to marry) but in subsequent years it has been extended to many other Articles of the Convention. It is in relation to art.6 (the right to a fair trial) that the Charter’s influence has been most noticeable so far, the Court having changed its position on two important aspects of Article 6 partly because of the wording of the EU Charter. But the influence on art.3 (in relation to the rights of asylum seekers), art.7 (in relation to retroactive penal laws), art.9 (in relation to the right to conscientious objection) and art.11 (in relation to rights of trades unions) has also been significant. The potential for the Charter to have greater influence on the Court’s jurisprudence in years to come remains considerable.

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The “religious understanding” of dignity is a topic of considerable complexity and is the subject of extensive scholarship. In this paper, I consider understandings of dignity that are currently under discussion in Roman Catholic circles, not least because Catholic discussions of dignity are often seen as influential in public policy and legal interpretation, directly and indirectly. I shall focus on one relatively neglected issue in legal scholarship: how scholars go about the task of identifying what a particular religion’s understanding of human dignity involves.
To illustrate the methodological problems that such an enterprise raises, I shall take one attempt by a scholar writing in the field of secular legal scholarship to describe Catholic understandings of dignity in the context of abortion and same-sex marriage. The discussion is that of Reva Siegel, an academic lawyer at Yale University; her recent analysis of differing understandings of dignity illustrates some of the issues that arise when the secular scholarly community addresses religious understandings of dignity.

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The article considers the use of comparisons in constitutional development, specifically the use of comparative reasoning in the context of debates about human rights in newly emerging independent states, using the examples of Ireland and Scotland.

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The discussion of human dignity raises such complex issues, and the issues that current scholarship now considers central to its understanding are so daunting, that we are in danger of not being able to see the forest for the trees. This Introduction forms the first chapter of a book of essays (Christopher McCrudden (ed.), UNDERSTANDING HUMAN DIGNITY,
Proceedings of the British Academy/Oxford University Press, in press) by a multi-disciplinary group of historians, legal academics, judges, political scientists, theologians, and philosophers, arising from a Conference held in Rhodes House, Oxford In June 2012. The Introduction aims to provide a guide, a map, through the thicket of current dignity scholarship. It situates the subsequent chapters of the book within an overview of the terrain that currently constitutes debates about the use of dignity in these fields. I have not attempted to put forward my own
comprehensive account of dignity. Mostly based on the rich conversations that took place at the Conference, I have sought, rather, to probe the potential strengths and weaknesses of all of the principal positions identified, at least in some contexts taking on the role of a Devil’s Advocate.

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Background: Large-scale biological jobs on high-performance computing systems require manual intervention if one or more computing cores on which they execute fail. This places not only a cost on the maintenance of the job, but also a cost on the time taken for reinstating the job and the risk of losing data and execution accomplished by the job before it failed. Approaches which can proactively detect computing core failures and take action to relocate the computing core's job onto reliable cores can make a significant step towards automating fault tolerance. Method: This paper describes an experimental investigation into the use of multi-agent approaches for fault tolerance. Two approaches are studied, the first at the job level and the second at the core level. The approaches are investigated for single core failure scenarios that can occur in the execution of parallel reduction algorithms on computer clusters. A third approach is proposed that incorporates multi-agent technology both at the job and core level. Experiments are pursued in the context of genome searching, a popular computational biology application. Result: The key conclusion is that the approaches proposed are feasible for automating fault tolerance in high-performance computing systems with minimal human intervention. In a typical experiment in which the fault tolerance is studied, centralised and decentralised checkpointing approaches on an average add 90% to the actual time for executing the job. On the other hand, in the same experiment the multi-agent approaches add only 10% to the overall execution time

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Espécies de Aeromonas encontram-se distribuídas por diferentes habitats, estando especialmente relacionadas com ambientes aquáticos. O seu papel em complicações na saúde humana e animal é reconhecido. De facto, não só pelo seu potencial de virulência, mas também pelos determinantes genéticos de resistência a antibióticos que possam conter, estes organismos constituem uma preocupação na medicina humana e veterinária. Assim, é essencial o estudo da diversidade de espécies de Aeromonas bem como explorar as suas características fenotípicas e genéticas que podem conduzir a impactos negativos. A água constitui um importante veículo de transmissão de microrganismos e espécies de Aeromonas estão amplamente distribuídas em águas tratadas e não tratadas. Em Portugal é ainda comum o consumo de águas não tratadas cuja qualidade, na maioria das vezes, não é sujeita a monitorização, como acontece por exemplo, em explorações agrícolas de gestão familiar. Neste estudo, investigou-se a presença de Aeromonas em águas não tratadas para consumo. Estabeleceu-se também uma linha horizontal de colheitas de diferentes amostras de origem agrícola com o intuito de avaliar a possibilidade de a água ser uma das vias de contaminação de culturas agrícolas e animais por espécies de Aeromonas. Obtiveram-se 483 isolados que foram discriminados por RAPD-PCR. 169 estirpes distintas foram identificadas ao nível da espécie por análise filogenética baseada no gene gyrB. Verificou-se uma frequente ocorrência bem como uma diversidade considerável de espécies de Aeromonas. Em alguns casos, as relações genotípicas entre isolados de diferentes amostras eram muito próximas. Adicionalmente, a maioria das amostras continha diferentes espécies e estirpes distintas da mesma espécie. A. media e A. hydrophila foram as espécies mais ocorrentes. Um grupo de isolados apresentou variantes moleculares de gyrB diferente das conhecidas até agora, o que indica que poderão constituir espécies não descritas. O perfil de susceptibilidade da colecção de Aeromonas a diferentes antibióticos foi estabelecido, constituindo um perfil típico do género, com algumas excepções. Estirpes multirresistentes foram encontradas. A presença de genes tet e bla foi investigada por estudos de PCR, hibridação e, em alguns casos, de sequenciação. Como era esperado, cphA/imiS foi o mais detectado. A detecção de integrões fez-se por PCR e hibridação e a sua caracterização foi feita por sequenciação de DNA; a sua ocorrência foi reduzida. A maioria das estirpes sintetizou enzimas extracelulares com actividade lipolítica e proteolítica que potencialmente contribuem para virulência. A análise por PCR e hibridação permitiram a detecção de vários determinantes genéticos que codificam moléculas possivelmente envolvidas em processos patogénicos. Diversas espécies de Aeromonas apresentando características relacionadas com resistência a antibióticos e potencialmente de virulência estão frequentemente presentes em produtos para consumo humano e animal em Portugal. ABSTRACT: Aeromonas spp. are present in a wide range of ecological niches, being mainly related to aquatic environments. Their role in human and animal health complications is recognised. In fact, not only for their putative virulence but also for the antibiotic resistance genetic determinants Aeromonas may harbour, these organisms constitute an issue of concern in human and veterinary medicine. Thus, it is essential to get knowledge on Aeromonas sp. diversity and on their genotypic and phenotypic characteristics that may lead to negative impacts. Water constitutes a good contamination route for microorganisms and Aeromonas are widespread in untreated and treated waters from different sources. In Portugal there is still an extensive use of untreated water which is not regularly monitored for quality. This is often the case in family smallholding farms. In this study untreated drinking and mineral waters were assessed for their content in Aeromonas spp. Furthermore, a sampling scheme was designed to investigate the occurrence and diversity of Aeromonas sp. in different agricultural correlated sources and to assess the possibility of water being the transmission vehicle between those sources. 483 isolates were obtained and discriminated by RAPD-PCR. Identification at the species level for 169 distinct strains was done by gyrB based phylogenetic analysis. Results demonstrated the frequent occurrence and considerable diversity of Aeromonas spp. In some cases, genotypic close relations were found between isolates from different sources. Also, most samples contained different species and distinct strains of the same species. A. media and A. hydrophila were the most occurring. A group of isolates displayed gyrB gene sequences distinct from the previously known, indicating that they may constitute representatives of non-described species. The antibiotic susceptibility profile of the aeromonads collection was established and constituted a typical profile of the genus, although few exceptions. Multiresistance patterns were found. The presence of tet and bla genes was investigated by PCR, hybridisation and, in some cases, sequencing analysis. As expected, cphA/imiS was the most detected. Integrons were screened by PCR and hybridisation and characterised by DNA sequencing; low occurrence was recorded. The bulk of strains was able to produce extracellular enzymes with lipolytic and proteolytic activities, which may contribute to virulence. PCR and hybridisation surveys allowed the detection of distinct genetic determinants coding for molecules putatively involved in pathogenic processes. Diverse Aeromonas sp. presenting distinct antibiotic resistance features and putative virulence traits are frequently present in many sources for human and animal consumption in Portugal.

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More than 3000 types of active pharmaceutical ingredients (APIs) are applied in Human and veterinary medicine practice. These compounds are considered an emergent class of environmental contaminants with the ability to cause damage and unexpected effects to aquatic organisms, namely in species of high commercial value. APIs are ubiquitous in the environment being frequently detected in influents and effluents of waste water treatment plants (WWTPs), surface waters and more distressingly in the public tap water in concentrations ranging from ng to μg.L-1. Considering these premises, the present thesis focused on APIs detection in the Arade river water, the impact of summer period in APIs’ concentration alterations applying the passive sampler device, POCIS (polar organic compound integrative sampler), as well as, the assessment of the effects caused by non-steroidal anti-inflammatory drugs (NSAID) ibuprofen (IBU) and diclofenac (DCF) and antidepressant selective serotonin reuptake inhibitor (SSRI) fluoxetine as single and mixture exposures along with a classical contaminant copper (Cu) on a non-target species, mussel Mytilus galloprovincialis. For this purpose, a multibiomarker approach was applied namely including biomarkers of oxidative stress (antioxidant enzymes activities of superoxide dismutase – SOD, catalase – CAT, glutathione reductase – GR and Phase II glutathione-S-transferase), damage - lipid peroxidation (LPO), neurotoxic effects (through the activity of acetylcholinesterase enzyme - AChE) and endocrine disruption (through vitellogenin-like proteins measurement applying the indirect method of alkali-labile phosphate - ALP) after exposure of mussel species’ to selected APIs at environmental relevant concentrations. The main results highlighted the occurrence of 19 APIs in the river Arade from several distinct therapeutic classes. Stimulant caffeine, antiasthmatic theophylline, NSAID ibuprofen and analgesic paracetamol presented the highest concentrations. Summer impact was inconclusive due to each API transient concentration in each month. The multibiomarker results revealed distinct responses towards each selected API (as single exposure or as mixtures) that were tissue and time dependent. Several multistressor interactions were proposed for each biomarker. The results also revealed APIs potential to induce oxidative stress, LPO, neurotoxicity and endocrine disruption even at extremely low concentrations on a species extremely vulnerable to APIs presence highlighting the urgency on the development of methodologies able to prevent its entrance in the aquatic environment.

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Tese de doutoramento, Ciências e Tecnologias da Saúde (Microbiologia), Universidade de Lisboa, Faculdade de Medicina, 2014

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Currently available rabies post-exposure prophylaxis (PEP) for use in humans includes equine or human rabies immunoglobulins (RIG). The replacement of RIG with an equally or more potent and safer product is strongly encouraged due to the high costs and limited availability of existing RIG. In this study, we identified two broadly neutralizing human monoclonal antibodies that represent a valid and affordable alternative to RIG in rabies PEP. Memory B cells from four selected vaccinated donors were immortalized and monoclonal antibodies were tested for neutralizing activity and epitope specificity. Two antibodies, identified as RVC20 and RVC58 (binding to antigenic site I and III, respectively), were selected for their potency and broad-spectrum reactivity. In vitro, RVC20 and RVC58 were able to neutralize all 35 rabies virus (RABV) and 25 non-RABV lyssaviruses. They showed higher potency and breath compared to antibodies under clinical development (namely CR57, CR4098, and RAB1) and commercially available human RIG. In vivo, the RVC20–RVC58 cocktail protected Syrian hamsters from a lethal RABV challenge and did not affect the endogenous hamster post-vaccination antibody response.

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Neurological disorders are a major concern in modern societies, with increasing prevalence mainly related with the higher life expectancy. Most of the current available therapeutic options can only control and ameliorate the patients’ symptoms, often be-coming refractory over time. Therapeutic breakthroughs and advances have been hampered by the lack of accurate central nervous system (CNS) models. The develop-ment of these models allows the study of the disease onset/progression mechanisms and the preclinical evaluation of novel therapeutics. This has traditionally relied on genetically engineered animal models that often diverge considerably from the human phenotype (developmentally, anatomically and physiologically) and 2D in vitro cell models, which fail to recapitulate the characteristics of the target tissue (cell-cell and cell-matrix interactions, cell polarity). The in vitro recapitulation of CNS phenotypic and functional features requires the implementation of advanced culture strategies that enable to mimic the in vivo struc-tural and molecular complexity. Models based on differentiation of human neural stem cells (hNSC) in 3D cultures have great potential as complementary tools in preclinical research, bridging the gap between human clinical studies and animal models. This thesis aimed at the development of novel human 3D in vitro CNS models by integrat-ing agitation-based culture systems and a wide array of characterization tools. Neural differentiation of hNSC as 3D neurospheres was explored in Chapter 2. Here, it was demonstrated that human midbrain-derived neural progenitor cells from fetal origin (hmNPC) can generate complex tissue-like structures containing functional dopaminergic neurons, as well as astrocytes and oligodendrocytes. Chapter 3 focused on the development of cellular characterization assays for cell aggregates based on light-sheet fluorescence imaging systems, which resulted in increased spatial resolu-tion both for fixed samples or live imaging. The applicability of the developed human 3D cell model for preclinical research was explored in Chapter 4, evaluating the poten-tial of a viral vector candidate for gene therapy. The efficacy and safety of helper-dependent CAV-2 (hd-CAV-2) for gene delivery in human neurons was evaluated, demonstrating increased neuronal tropism, efficient transgene expression and minimal toxicity. The potential of human 3D in vitro CNS models to mimic brain functions was further addressed in Chapter 5. Exploring the use of 13C-labeled substrates and Nucle-ar Magnetic Resonance (NMR) spectroscopy tools, neural metabolic signatures were evaluated showing lineage-specific metabolic specialization and establishment of neu-ron-astrocytic shuttles upon differentiation. Chapter 6 focused on transferring the knowledge and strategies described in the previous chapters for the implementation of a scalable and robust process for the 3D differentiation of hNSC derived from human induced pluripotent stem cells (hiPSC). Here, software-controlled perfusion stirred-tank bioreactors were used as technological system to sustain cell aggregation and dif-ferentiation. The work developed in this thesis provides practical and versatile new in vitro ap-proaches to model the human brain. Furthermore, the culture strategies described herein can be further extended to other sources of neural phenotypes, including pa-tient-derived hiPSC. The combination of this 3D culture strategy with the implemented characterization methods represents a powerful complementary tool applicable in the drug discovery, toxicology and disease modeling.

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Conflicts over human rights in relations between East Asia and the West have increased since the end of the Cold War. Western governments express concern about human rights standards in East Asian countries. In the East, these expressions have been perceived as interference in internal affairs. Due to dramatic economic development, East Asian nations recently have gained in pride and self-confidence as global actors. Such development is observed with suspicion in the West. Concerned about the decline of global U.S. influence, some American scholars have re-invented the notion of "culture" to point at an alleged East Asian threat. Also East Asian statesmen use the cultural argument by claiming the existence of so-called 'Asian values', which they allege are the key to Eastern economic success. This thesis argues that issues of human rights in East-West relations are not only a consequence of well-intended concern by Western governments regarding the human rights and welfare of the citizens of East Asian nations, but are in fact dominated by and used as a pawn in interplay with more complicated questions of global power and economic relations between East and West. The thesis reviews the relevance of culture in East-West relations. In the West, particularly Samuel P. Huntington with his prediction of the Clash of Civilizations stands out. Singapore's Lee Kuan Yew has been very vocal on the Eastern side. Whereas the West tries to cope with its decrease of global influence, after hundreds of years under Western hegemonism, the East believes in an Asian way of development without interference form the West. Most of this dispute revolves around the issue of human rights. The West claims the universality of rights which in fact emphasizes political and civil rights. Western countries critizise poor human rights standards in East Asia. The East, in return, accuses the West of hypocritical policies that seek global dominance. East Asian governments assert that due to a different stage of development they have to stress first their rights to development in order to assure stability. In particular, China argues this way. The country's leadership, however, shows concern about human rights and has already improved its human rights record over the past years. This thesis analyses the dispute over human rights in a case study on Germany and China. Both countries have a mutual interest in trade relations which has conflicted with Germany's criticism of China's problematic human rights record. In 1996, the two countries clashed after the German parliament passed a resolution condemning China's treatment of Tibet. This caused a lot of damage to the Chinese-German relationship which in the course of the year went back to normality. In the light of these frictions a German human rights policy that focuses on unspectacular grass-roots support of China, for example in strengthening China's legal system, would be preferable. Such co-operation must be based on mutual respect.

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Pancreatic deoxyribonuclease preferentially digests active genes during all phases of the cell cycle including mitosis. Recently, a DNAse I-directed in ~ nick translation technique has been used to demonstrate differences in the DNAse I sensitivity of euchromatic and heterochromatic regions of mitotic chromosomes. This ill ~ technique has been used in this study to ask whether facultative heterochromatin of the inactive X chromosome can be distinguished from the active X chromosome in mouse and human tissues. In addition to this, in ~ nick translation has been used to distinguish constitutive heterochromatin in mouse and human mitotic chromosomes. Based on relative levels of DNAse I sensitivity, the inactive X chromosome could not be distinguished from the active X chromosome in either mouse or human tissues but regions of constitutive heterochromatin could be distinguished by their relative DNAse I insensitivity. The use of !D situ nick translation was also applied to tissue sections of 7.5 day mouse embryos to ask whether differing levels of DNAse I sensitivity could be detected between different tissue types. Differences in DNAse I sensitivities were detected in three tissues examined; embryonic ectoderm, an embryo-derived tissue, and two extraembryonic tissues, extraembryonic ectoderm and ectoplacental cone. Embryonic ectoderm and extraembryonic ectoderm nuclei possessed comparable levels of DNAse I sensitivity while ectoplacental cone was significantly less DNAse I sensitive. This suggests that tissue-specific mechanisms such as chromatin structure may be involved in the regulation of gene activity in certain tissue types. This may also shed some light on possible tissue specific mechanisms regulating X chromosome activity in the developing mouse embryo.