992 resultados para Medicine Sanitary Regulation
Resumo:
Forensic experts play a major role in the legal process as they offer professional expert opinion and evidence within the criminal justice system adjudicating on the innocence or alleged guilt of an accused person. In this respect, medico-legal examination is an essential part of the investigation process, determining in a scientific way the cause(s) and manner of unexpected and/or unnatural death or bringing clinical evidence in case of physical, psychological, or sexual abuse in living people. From a legal perspective, these types of investigation must meet international standards, i.e., it should be independent, effective, and prompt. Ideally, the investigations should be conducted by board-certified experts in forensic medicine, endowed with a solid experience in this field, without any hierarchical relationship with the prosecuting authorities and having access to appropriate facilities in order to provide forensic reports of high quality. In this respect, there is a need for any private or public national or international authority including non-governmental organizations seeking experts qualified in forensic medicine to have at disposal a list of specialists working in accordance with high standards of professional performance within forensic pathology services that have been successfully submitted to an official accreditation/certification process using valid and acceptable criteria. To reach this goal, the National Association of Medical Examiners (NAME) has elaborated an accreditation/certification checklist which should be served as decision-making support to assist inspectors appointed to evaluate applicants. In the same spirit than NAME Accreditation Standards, European Council of Legal Medicine (ECLM) board decided to set up an ad hoc working group with the mission to elaborate an accreditation/certification procedure similar to the NAME's one but taking into account the realities of forensic medicine practices in Europe and restricted to post-mortem investigations. This accreditation process applies to services and not to individual practitioners by emphasizing policies and procedures rather than professional performance. In addition, the standards to be complied with should be considered as the minimum standards needed to get the recognition of performing and reliable forensic pathology service.
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In many insect societies, workers can manipulate the reproductive output of their colony by killing kin of lesser value to them. For instance, workers of the mound-building For mica exsecta eliminate male brood in colonies headed by a single-mated queen. By combining an inclusive fitness model and empirical data, we investigated the selective causes underlying these fratricides. Our model examines until which threshold stage in male brood development do the workers benefit from eliminating males to rear extra females instead. We then determined the minimal developmental stage reached by male larvae before elimination in F. exsecta field colonies. Surprisingly, many male larvae were kept until they were close to pupation, and only then eliminated. According to our model, part of the eliminated males were so large that workers would not benefit from replacing them with new females. Moreover, males were eliminated late in the season, so that new females could no longer be initiated, because matings take place synchronously during a short period. Together, these results indicate that workers did not replace male brood with new females, but rather reduced total brood size during late larval development. Male destruction was probably triggered by resource limitation, and the timing of brood elimination suggests that males may have been fed to females when these start to grow exponentially during the final larval stage. Hence, the evolution of fratricides in ants is best explained by a combination of ecological, demographic and genetic parameters.
Resumo:
ABSTRACTThis study aims to elucidate the bionomy of Peckia(Sarcodexia) lambens and Oxysarcodexia amorosa to provide data for medical, veterinary and forensic entomology analyses. We analyzed larval stage duration (L1–L3), weight of the mature larvae (L3), pupal stage duration, L1–adult duration, adult emergence and viability of larvae and adults of both species. Larval viability of P. (S.) lambens was 82% and the mean duration of the larval stage was 3.51 ± 0.99 days. The mature larvae had a mean weight of 33.67 ± 7.13 mg. The mean duration of the pupal stage was 8.26 ± 0.93 days and the mean duration of the L1–adult was 11.53 ± 1.22 days. Mean lifespan for females and males was 39.33 ± 1.52 and 57.33 ± 4.72 days, respectively. Larval viability of O. amorosa was 76% and mean duration of larval stage was 3.51 ± 0.64 days. Mature larvae had a mean weight of 28.28 ± 3.38 mg. Mean duration of the pupal stage was 10.14 ± 0.63 days and mean duration of the L1–adult was 13.60 ± 0.69 days. Mean lifespan for females and males was 83.66 ± 15.94 and 84.00 ± 19.97 days, respectively. Oxysarcodexia amorosa showed a L1–adult stage longer than P. (S.) lambens; however both species showed low viability. O. amorosa laid more larvae than P. (S.) lambens, this fact may occur because O. amorosa had longer life duration.
Resumo:
The Work Package 4 of the ORAMED project, a collaborative project (2008-11) supported by the European Commission within its seventh Framework Programme, is concerned with the optimisation of the extremity dosimetry of medical staff in nuclear medicine. To evaluate the extremity doses and dose distributions across the hands of medical staff working in nuclear medicine departments, an extensive measurement programme has been started in 32 nuclear medicine departments in Europe. This was done using a standard protocol recording all relevant information for radiation exposure, i.e. radiation protection devices and tools. This study shows the preliminary results obtained for this measurement campaign. For diagnostic purposes, the two most-used radionuclides were considered: (99m)Tc and (18)F. For therapeutic treatments, Zevalin(®) and DOTATOC (both labelled with (90)Y) were chosen. Large variations of doses were observed across the hands depending on different parameters. Furthermore, this study highlights the importance of the positioning of the extremity dosemeter for a correct estimate of the maximum skin doses.
Resumo:
FXYD3 (Mat-8) proteins are regulators of Na,K-ATPase. In normal tissue, FXYD3 is mainly expressed in stomach and colon, but it is also overexpressed in cancer cells, suggesting a role in tumorogenesis. We show that FXYD3 silencing has no effect on cell proliferation but promotes cell apoptosis and prevents cell differentiation of human colon adenocarcinoma cells (Caco-2), which is reflected by a reduction in alkaline phosphatase and villin expression, a change in several other differentiation markers, and a decrease in transepithelial resistance. Inhibition of cell differentiation in FXYD3-deficient cells is accompanied by an increase in the apparent Na+ and K+ affinities of Na,K-ATPase, reflecting the absence of Na,K-pump regulation by FXYD3. In addition, we observe a decrease in the maximal Na,K-ATPase activity due to a decrease in its turnover number, which correlates with a change in Na,K-ATPase isozyme expression that is characteristic of cancer cells. Overall, our results suggest an important role of FXYD3 in cell differentiation of Caco-2 cells. One possibility is that FXYD3 silencing prevents proper regulation of Na,K-ATPase, which leads to perturbation of cellular Na+ and K+ homeostasis and changes in the expression of Na,K-ATPase isozymes, whose functional properties are incompatible with Caco-2 cell differentiation.
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Superantigens are defined by their ability to stimulate a large fraction of T cells via interaction with the T cell receptor (TCR) V beta domain. Endogenous superantigens, classically termed minor lymphocyte-stimulating (Mls) antigens, were recently identified as products of open reading frames (ORF) in integrated proviral copies of mouse mammary tumor virus (MMTV). We have described an infectious MMTV homologue of the classical endogenous superantigen Mls-1a (Mtv-7). The ORF molecules of both the endogenous Mtv-7 and the infectious MMTV(SW) interact with T cells expressing the TCR V beta 6, 7, 8.1, and 9 domains. Furthermore, the COOH termini of their ORF molecules, thought to confer TCR specificity, are very similar. Since successful transport of MMTV from the site of infection in the gut to the mammary gland depends on a functional immune system, we were interested in determining the early events after and requirements for MMTV infection. We show that MMTV(SW) infection induces a massive response of V beta 6+ CDC4+ T cells, which interact with the viral ORF. Concomitantly, we observed a B cell response and differentiation that depends on both the presence and stimulation of the superantigen-reactive T cells. Furthermore, we show that B cells are the main target of the initial MMTV infection as judged by the presence of the reverse-transcribed viral genome and ORF transcripts. Thus, we suggest that MMTV infection of B cells leads to ORF-mediated B-T cell interaction, which maintains and possibly amplifies viral infection.
Resumo:
The DNA repair enzyme O(6)-methylguanine-DNA methyltransferase (MGMT) antagonizes the genotoxic effects of alkylating agents. MGMT promoter methylation is the key mechanism of MGMT gene silencing and predicts a favorable outcome in patients with glioblastoma who are exposed to alkylating agent chemotherapy. This biomarker is on the verge of entering clinical decision-making and is currently used to stratify or even select glioblastoma patients for clinical trials. In other subtypes of glioma, such as anaplastic gliomas, the relevance of MGMT promoter methylation might extend beyond the prediction of chemosensitivity, and could reflect a distinct molecular profile. Here, we review the most commonly used assays for evaluation of MGMT status, outline the prerequisites for standardized tests, and evaluate reasons for difficulties in reproducibility. We critically discuss the prognostic and predictive value of MGMT silencing, reviewing trials in which patients with different types of glioma were treated with various chemotherapy schedules, either up-front or at recurrence. Standardization of MGMT testing requires comparison of different technologies across laboratories and prospectively validated cut-off values for prognostic or predictive effects. Moreover, future clinical trials will need to determine, for each subtype of glioma, the degree to which MGMT promoter methylation is predictive or prognostic, and whether testing should become routine clinical practice.
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The molecular mechanisms underlying transcription elongation and their role in gene regulation are poorly characterized in eukaryotes. A number of genes, however, have been proposed to be regulated at the level of transcription elongation, including c-myc, c-fos and c-myb. Here, we analyze the control of transcription elongation at the mouse c-fos gene at the nucleotide level in intact cells. We find that RNA polymerases are engaged in the promoter-proximal part of the gene in the absence of gene activation signals and mRNA synthesis. Importantly, we determine that the engaged RNA polymerases originate from a continuous initiation of transcription which, in the absence of gene activation signals, terminate close to the promoter. We also observe that the c-fos gene presents an active chromatin conformation, with the promoter and upstream regulatory sequences constitutively occupied by proteins, accounting for the continuous initiation of RNA polymerase complexes. We propose that activation of c-fos gene expression results primarily from the assembly of elongation-competent RNA polymerases that can transcribe the complete gene. Our results suggest that the engaged RNA polymerases found downstream of a number of other eukaryotic promoters may be associated with transcription termination of elongation-incompetent polymerases in the absence of activating signals.
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Five functional mammalian facilitated hexose carriers (GLUTs) have been characterized by molecular cloning. By functional expression in heterologous systems, their specificity and affinity for different hexoses have been defined. There are three high-affinity transporters (GLUT-1, GLUT-3 and GLUT-4) and one low-affinity transporter (GLUT-2), and GLUT-5 is primarily a fructose carrier. Because their Michaelis constants (Km) are below the normal blood glucose concentration, the high-affinity transporters function at rates close to maximal velocity. Thus their level of cell surface expression greatly influences the rate of glucose uptake into the cells. In contrast, the rate of glucose uptake by GLUT-2 (Km = 17 mM) increases in parallel with the rise in blood glucose over the physiological concentration range. High-affinity transporters are found in almost every tissue, but their expression is higher in cells with high glycolytic activity. Glut-2, however, is found in tissues carrying large glucose fluxes, such as intestine, kidney, and liver. As an adaptive response to variations in metabolic conditions, the expression of these transporters is regulated by glucose and different hormones. Thus, because of their specific characteristics and regulated expression, the facilitated glucose transporters control fundamental aspects of glucose homeostasis. I review data pertaining to the structure and regulated expression of the glucose carriers present in intestine, kidney, and liver and discuss their role in the control of glucose flux into or out of these different tissues.
Resumo:
Coordinated function of the innate and adaptive arms of the immune system in vertebrates is essential to promote protective immunity and to avoid immunopathology. The Notch signalling pathway, which was originally identified as a pleiotropic mediator of cell fate in invertebrates, has recently emerged as an important regulator of immune cell development and function. Notch was initially shown to be a key determinant of cell-lineage commitment in developing lymphocytes, but it is now known to control the homeostasis of several innate cell populations. Moreover, the roles of Notch in adaptive immunity have expanded to include the regulation of T cell differentiation and function. The aim of this Review is to summarize the current status of immune regulation by Notch. A better understanding of Notch function in both innate and adaptive immunity will hopefully provide multiple avenues for therapeutic intervention in disease.
Resumo:
In response to DNA damage, p53-induced protein with a death domain (PIDD) forms a complex called the PIDDosome, which either consists of PIDD, RIP-associated protein with a death domain and caspase-2, forming a platform for the activation of caspase-2, or contains PIDD, RIP1 and NEMO, important for NF-κB activation. PIDDosome activation is dependent on auto-processing of PIDD at two different sites, generating the fragments PIDD-C and PIDD-CC. Despite constitutive cleavage, endogenous PIDD remains inactive. In this study, we screened for novel PIDD regulators and identified heat shock protein 90 (Hsp90) as a major effector in both PIDD protein maturation and activation. Hsp90, together with p23, binds PIDD and inhibition of Hsp90 activity with geldanamycin efficiently disrupts this association and impairs PIDD auto-processing. Consequently, both PIDD-mediated NF-κB and caspase-2 activation are abrogated. Interestingly, PIDDosome formation itself is associated with Hsp90 release. Characterisation of cytoplasmic and nuclear pools of PIDD showed that active PIDD accumulates in the nucleus and that only cytoplasmic PIDD is bound to Hsp90. Finally, heat shock induces Hsp90 release from PIDD and PIDD nuclear translocation. Thus, Hsp90 has a major role in controlling PIDD functional activity.
Resumo:
The molecular mechanisms regulating the initial uptake of inorganic sulfate in plants are still largely unknown. The current model for the regulation of sulfate uptake and assimilation attributes positive and negative regulatory roles to O-acetyl-serine (O-acetyl-Ser) and glutathione, respectively. This model seems to suffer from exceptions and it has not yet been clearly validated whether intracellular O-acetyl-Ser and glutathione levels have impacts on regulation. The transcript level of the two high-affinity sulfate transporters SULTR1.1 and SULTR1.2 responsible for sulfate uptake from the soil solution was compared to the intracellular contents of O-acetyl-Ser, glutathione, and sulfate in roots of plants submitted to a wide diversity of experimental conditions. SULTR1.1 and SULTR1.2 were differentially expressed and neither of the genes was regulated in accordance with the current model. The SULTR1.1 transcript level was mainly altered in response to the sulfur-related treatments. Split-root experiments show that the expression of SULTR1.1 is locally regulated in response to sulfate starvation. In contrast, accumulation of SULTR1.2 transcripts appeared to be mainly related to metabolic demand and is controlled by photoperiod. On the basis of the new molecular insights provided in this study, we suggest that the expression of the two transporters depends on different regulatory networks. We hypothesize that interplay between SULTR1.1 and SULTR1.2 transporters could be an important mechanism to regulate sulfate content in the roots
Resumo:
The knowledge in internal medicine is constantly and so rapidly evolving that practices have to be updated and adjusted to recent scientific rules, in order to improve quality and efficiency in the day to day activities. Residents in the Service of internal medicine of the Lausanne University present several relevant papers published in 2012, whose results are susceptible to change the daily hospital practices. From modest impacts to real revolution, a variety of subjects are discussed in the perspective of evidence based medicine.