874 resultados para work-related injury or illness


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O presente Projeto Artístico propõe como principal objetivo a divulgação de obras para clarinete solo e para clarinete e eletrónica produzidas no seio das classes de clarinete e composição da Escola Superior de Música de Lisboa. A preparação e montagem da obra de Edward Luiz Ayres d’Abreu, aqui realizada em estreia absoluta, pretende manter viva a continuidade de produção artística desta instituição a todos os níveis, neste caso, entre dois estudantes. Neste relatório estão registados os benefícios alcançados com o trabalho de pesquisa relacionado com os aspectos biográficos dos compositores, o contexto da criação das obras, assim como a análise e apuramento de questões interpretativas pouco utilizadas na música convencional como por exemplo, as técnicas clarinetísticas contemporâneas (glissando, frulato, vibrato, som e voz, multifónicos, micro-tons), a prática de música com eletrónica, ou a experiência inovadora da recriação musical em palco de uma partitura gráfica.

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A Work Project, presented as part of the requirements for the Award of a Masters Degree in Management from the NOVA – School of Business and Economics

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A Work Project, presented as part of the requirements for the Award of a Masters Degree in Management from the NOVA – School of Business and Economics

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INTRODUCTION: Accidents caused by fish are common in inland fishing communities in Brazil, being work-related injuries in the majority of cases. These populations have no information on the mechanisms of trauma or envenoming. METHODS: Through a questionnaire administered to fishermen, we obtained clinical and epidemiological data on accidents in Rosana, Pontal do Paranapanema, State of São Paulo, Brazil. These data were analyzed and converted into an easily understood prevention and treatment program for the colony. RESULTS: Thirty-nine fishermen replied to the survey. All of the patients had been hurt by fish. Of those mentioned, the yellow catfish (Pimelodus maculatus) was the main fish species associated with injuries, but others also caused trauma to the fishermen. Six fishermen had been envenomed by stingrays. Pain and ulcers were the main symptoms and were described as intolerable. Approximately half of those injured were treated using traditional folk remedies. CONCLUSIONS: The fishermen suffered multiple accidents with catfish, which are venomous and cause intense pain, as well as trauma due to other fish, such as surubins, traíras, freshwater croakers, and piranhas. Approximately 16% of those interviewed presented with envenomation from stingrays. Our data and previous experience in the area led to the creation of a pamphlet with clear language that can effectively help fishermen in the region, an area in need of health services and disease prevention. This initiative also applies to the whole La Plata River basin, which has similar fauna.

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This report will describe the activities undertaken during my internship at the Personnel Department (DPE-UPE4.1) in Caixa Geral de Depósitos (CGD), Lisbon, between September 22, 2014, and February 28, 2015. I consider that it is important to note from the outset i) that the subject of my training was suggested by my supervisor in the DPE and accepted by me; and ii) that the internship consisted essentially of carrying out research and information gathering into the different social systems that coexist within the bank and the application of each legal system in solving concrete situations of the CGD employees. The research and analysis of information was important not only for my study but for the CGD itself, as it enables the department to have such an important matter, full of specific characteristics, condensed into a single document, i.e. this report. This is a complex reality. The various welfare systems differ according to the contractual agreement linking the employee to the employer at the date when the labour contract is signed, and also the unique/singular characteristics of the CGD. In the early stage I started by trying to understand the financial institution and its organization and role and the department where I worked. So I analyzed the CGD Statutes and the legal measures that crystallized the scheme for its employees and I also researched its domestic and international operations. The first month was devoted to the research and analysis of such legislation to understand the creation of the CGD and its path to date. In the second and third months I studied the legal social systems that are applied to different groups of CGD workers. This period was quite important to identify and understand the differences between those regimes of CGD employees as well as the procedure inherent in each case. I highlighted the non-implementation of “the social protection regime of convergence” to the workers of this institution; the differences regarding the allocation of sickness subsidies paid to workers who belong to Social Security and CGA contributors, as well as the enforcement of internal rules to all the workers when a work-related accident happens. Then I focused on to assessing and examining external legislation and several internal regulations in order to obtain solutions to questions raised and situations involving by the workers, in order to understand how the DPE solves these situations. Over the last three months of internship, after this more theoretical work, I began the analysis of concrete situations involving employees carrying out their duties in Portugal and abroad. Some of these situations had been received by the department before the beginning of my internship and others over this period. When I was “working” in the DPE I analyzed “cases” that had been solved and some others without a final solution because they were still in courts. As for the last ones (new cases) I was able to follow their assessment and sometimes their outcome. Some of them became study cases for me. Over these five months of my internship, several cases were analyzed and discussed by legal experts of DPE in which I could participate. I always worked hard. I know that this action contributed to elucidate me about the treatment of the issues, and allowed me to have a direct contact with some workers and be part of a dynamic work team. For these reasons, my internship report is not merely descriptive of activities. It consists of an analysis of rules (legislation) and a regulatory framework of activities and it is also a description of several specific situations solved or in a solution process. Through this work I intend to make known the particular reality of a modern Portuguese financial institution not only because of its importance in our country but also such a large number of employees work here (in Portugal and abroad). I should add that throughout my internship I was allowed to attend conferences, within the scope of the bank in order to get a broader view of some issues related to the daily life of the DPE and the CGD. So, I participated in I Jornadas Bancárias and the Conferência Internacional do Contrato a Termo, given that the CGD is a bank and the DPE deals with legal and labour relations.

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Abstract: Scorpion stings are currently the leading cause of venom-related injury to humans in Brazil and are a significant public health problem globally. Only scorpions of the Tityus genus are of medical importance in Brazil, and Tityus serrulatus is responsible for the most serious envenomations and deaths. The toxic effects of scorpion envenomation are due to a massive release of sympathetic and parasympathetic neurotransmitters; the severity is related to cardiac and hemodynamic changes, with cardiogenic shock and pulmonary edema contributing to the main causes of death. The pathophysiology of cardiac involvement has been discussed for decades and has been attributed to adrenergic discharge and a possible toxic effect of venom on the myocardium, while acute pulmonary edema may have a cardiogenic and/or non-cardiogenic origin. Currently, the clinical data point to catecholamine excess as the cause for reversible scorpion cardiomyopathy . These data include electrocardiographic changes, profiling of cardiac enzymes and troponin I, echocardiographic data with global or regional left ventricle dysfunction, and myocardial perfusion alterations compatible with spasm in the coronary microcirculation. Furthermore, recent data on cardiac magnetic resonance imaging findings, which are similar to those observed for stress-induced cardiomyopathy, have also been linked to catecholamine excess. The efficiency of antivenom serum treatment is controversial in the literature. Our experience in Brazil is that the management of patients with systemic manifestations of scorpion stings is based on three approaches, all of which are extremely important. These include symptomatic treatment, antivenom serum, and cardiorespiratory support.

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RESUMO - A dor, incómodo ou desconforto ao nível músculo-esquelético, sobretudo devido a situações e/ou postos de trabalho com elevadas exigências ao nível postural, de aplicação de força, de repetitividade ou por incorrecta distribuição das pausas, é aceite como um indicador de situações de risco passíveis de se encontrarem na génese de lesões músculo- -esqueléticas ligadas ao trabalho (LMELT) (Stuart-Buttle, 1994). No sentido de avaliar a prevalência de sintomas de LME, efectuou-se um estudo numa grande empresa da indústria de componentes para automóveis na região de Lisboa durante o ano de 2001. Utilizou-se um instrumento de recolha de informação construído a partir de uma adaptação do questionário nórdico músculo-esquelético (QNM) (Kuorinka et al., 1987). Com o apoio do serviço de saúde ocupacional da referida empresa, o questionário foi entregue a todos os trabalhadores, obtendo-se uma taxa de respondentes de 63,2% (n = 574). A população em estudo é maioritariamente do sexo feminino (83,9%), tem idades compreendidas entre os 18 e os 65 anos e a classe modal situa-se entre os 26 e os 33 anos (23,3%). Os resultados evidenciam uma alta prevalência de sintomatologia de LME e diferenças significativas de sintomas entre as categorias profissionais (1) operadores de máquina de costura, (2) trabalhadores dos armazéns e de transporte de mercadorias e (3) trabalhadores da logística, qualidade e escritórios. Os operadores apresentam índices superiores e diferentes (p < 0,05) de sintomatologia nos últimos doze meses ao nível da região cervical, ombros, cotovelos, ancas/coxas, pernas/joelhos e tornozelos/pés e nos punhos nos últimos sete dias. No presente estudo, a análise dos dados obtidos parece indicar que a natureza e as características da actividade de trabalho do grupo profissional operadores de máquina de costura (flexão cervical > 20°, trabalho muscular predominantemente estático ao nível da articulação dos ombros, elevação dos membros superiores > 45°, ortostatismo e exigências elevadas ao nível dos punhos/mãos) estão implicadas no desencadear da sintomatologia auto- -referida.

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This report will describe the activities undertaken during my internship at the Personnel Department (DPE-UPE4.1) in Caixa Geral de Depósitos (CGD), Lisbon, between September 22, 2014, and February 28, 2015. I consider that it is important to note from the outset i) that the subject of my training was suggested by my supervisor in the DPE and accepted by me; and ii) that the internship consisted essentially of carrying out research and information gathering into the different social systems that coexist within the bank and the application of each legal system in solving concrete situations of the CGD employees. The research and analysis of information was important not only for my study but for the CGD itself, as it enables the department to have such an important matter, full of specific characteristics, condensed into a single document, i.e. this report. This is a complex reality. The various welfare systems differ according to the contractual agreement linking the employee to the employer at the date when the labour contract is signed, and also the unique/singular characteristics of the CGD. In the early stage I started by trying to understand the financial institution and its organization and role and the department where I worked. So I analyzed the CGD Statutes and the legal measures that crystallized the scheme for its employees and I also researched its domestic and international operations. The first month was devoted to the research and analysis of such legislation to understand the creation of the CGD and its path to date. In the second and third months I studied the legal social systems that are applied to different groups of CGD workers. This period was quite important to identify and understand the differences between those regimes of CGD employees as well as the procedure inherent in each case. I highlighted the non-implementation of “the social protection regime of convergence” to the workers of this institution; the differences regarding the allocation of sickness subsidies paid to workers who belong to Social Security and CGA contributors, as well as the enforcement of internal rules to all the workers when a work-related accident happens.Then I focused on to assessing and examining external legislation and several internal regulations in order to obtain solutions to questions raised and situations involving by the workers, in order to understand how the DPE solves these situations. Over the last three months of internship, after this more theoretical work, I began the analysis of concrete situations involving employees carrying out their duties in Portugal and abroad. Some of these situations had been received by the department before the beginning of my internship and others over this period. When I was “working” in the DPE I analyzed “cases” that had been solved and some others without a final solution because they were still in courts. As for the last ones (new cases) I was able to follow their assessment and sometimes their outcome. Some of them became study cases for me. Over these five months of my internship, several cases were analyzed and discussed by legal experts of DPE in which I could participate. I always worked hard. I know that this action contributed to elucidate me about the treatment of the issues, and allowed me to have a direct contact with some workers and be part of a dynamic work team. For these reasons, my internship report is not merely descriptive of activities. It consists of an analysis of rules (legislation) and a regulatory framework of activities and it is also a description of several specific situations solved or in a solution process. Through this work I intend to make known the particular reality of a modern Portuguese financial institution not only because of its importance in our country but also such a large number of employees work here (in Portugal and abroad). I should add that throughout my internship I was allowed to attend conferences, within the scope of the bank in order to get a broader view of some issues related to the daily life of the DPE and the CGD. So, I participated in I Jornadas Bancárias and the Conferência Internacional do Contrato a Termo, given that the CGD is a bank and the DPE deals with legal and labour relations.

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RESUMO - A frequente insuficiência de informação e até, eventualmente, a presença de elementos cientificamente pouco robustos (ou mesmo hipotéticos) no procedimento de obtenção dos resultados finais (scores) com os diversos métodos de avaliação do risco, julga-se determinar a obtenção de distintos resultados no mesmo posto de trabalho e que interessam analisar. O presente estudo foi efectuado numa empresa da indústria automóvel e pretendeu contribuir para a efectividade do processo de avaliação do risco destas lesões em meio industrial. Utilizaram-se como ponto de partida as classificações de risco em postos de trabalho onde a aplicação do método OCRA — base do projecto de norma Europeu prEN 1005-5 para a estimativa do risco de LMEMSLT (Lesões Musculoesqueléticas do Membro Superior Ligadas ao Trabalho) — identificou níveis de risco moderados e/ou elevados (score OCRA ≥ 16,5). Assim nos postos de trabalho (n = 71) registou-se em vídeo a actividade de trabalho. Analisaram-se os principais factores de risco (postura, força, repetitividade e exposição a vibrações) com uma amostragem de segundo em segundo e aplicaram-se dois métodos: 1) RULA (McAtamney; Corlett, 1993); 2) SI (Moore; Garg, 1995). Dos resultados globais da aplicação dos métodos identificam- se discrepâncias evidentes: o método SI classificou 41 postos de risco elevado e o método RULA classificou apenas 26 postos de risco. Destaque para as divergências entre os postos classificados de risco elevado como, por exemplo: de entre os 41 postos com scores de risco da aplicação do método SI apenas se encontram 12 postos classificados de risco pelo método RULA. Os resultados permitem evidenciar validades preditivas diversas para os factores de risco analisados: 1) situações de aplicação de força (SI = 0,80; RULA = 0,66); 2) presença de posturas extremas (SI = 0,68; RULA = 0,48); 3) repetitividade (SI = 0,35; RULA = 0,43). Conclui-se pela divergência de resultados dos métodos SI e RULA aplicados nos mesmos postos de trabalho que tal situação alerta para a pertinência da utilização de um filtro que permita a identificação dos factores de risco presentes em cada posto de trabalho e que, por consequência, oriente a selecção do método mais indicado ou ainda, em oposição, do método contra-indicado. Este trabalho, como um contributo para uma efectiva identificação e avaliação do risco de LMEMSLT, conduz, no limite, à necessidade de elaboração de uma «grelha» das «grelhas» e de informação mais precisa sobre os métodos e sua aplicação, permitindo, desse modo, uma mais efectiva gestão do risco destas lesões.

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RESUMO - As lesões musculoesqueléticas ligadas ao trabalho (LMELT) são frequentes em contexto hospitalar e particularmente entre os enfermeiros (Estryn-Béhar, 1991; NIOSH, 1997). Em meio ocupacional o diagnóstico destas patologias é, com frequência, realizado com recurso a questionários de sintomas. A aplicação de questionários de auto-referência de sintomas de LMELT tem permitido recolher informação sobre a prevalência europeia destas lesões, registando-se valores que oscilam entre os 17 e os 44% (Buckle, 1999) e entre nós, designadamente numa indústria de componentes automóveis, os valores apresentam dimensão semelhante ou superior (Serranheira et al., 2003). O presente estudo pretendeu identificar a sintomatologia musculoesquelética auto-referida pelos enfermeiros em meio hospitalar, procurando relações com a actividade de enfermagem. Utilizou-se um instrumento de recolha de informação construído a partir de uma adaptação do questionário nórdico musculoesquelético (QNM) (Kuorinka et al., 1987) que se aplicou a 899 enfermeiros de diferentes serviços em cinco hospitais da região do grande Porto, no ano de 2004 (responderam 507 enfermeiros). Os resultados evidenciam uma prevalência elevada de sintomas musculoesqueléticos em diferentes zonas anatómicas nos últimos 12 meses (84%), particularmente atingindo a região lombar (65%), cervical (55%), dorsal (37%), ombros (34%) e punhos/mãos (30%). Não se encontram associações significativas entre algumas actividades que os enfermeiros realizam e a presença de níveis de desconforto, incómodo ou dor com origem no sistema musculoesquelético, eventualmente devido ao elevado número de subactividades desempenhadas pelos enfermeiros. Apesar disso, existem algumas relações: (1) com a tipologia de actividades realizadas (por exemplo levantamento e transporte de cargas) nos diferentes serviços (destaca-se a Medicina e a Neonatologia), (2) com o aumento do número de horas de trabalho semanais. Desse modo, observa-se que a prevalência de sintomas de LMELT neste grupo profissional é elevada o que pode condicionar a actividade dos enfermeiros e, por consequência, o bem-estar dos utentes. Sugere-se que a actividade de enfermagem e a organização do trabalho deste grupo profissional sejam objecto de uma análise mais detalhada no sentido da identificação dos elementos determinantes da sintomatologia musculoesquelética e sua consequente prevenção.

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Work-related musculoskeletal disorders (WMSD) became one of the biggest health problems in the workplace and one of the main concerns of ergonomics and despite all the technical improvements manual handling is still an important risk factor for WMSD. The current study was performed with the main objective of conducting an ergonomic analysis in a workplace that consists in packaging products in a pallet, in a food distribution industry, also called picking. In this perspective, the aim of the study is to identify if the tasks performed by operators present any risk of WMSD and, if so, to suggest proposals for minimizing the associated effort. The methodologies of ergonomic risk assessment that were initially applied were the Risk Reckoner and the Manual Handling Assessment Chart (MAC). Subsequently, in order to, on the one hand, complement the analysis performed using the two methods previously mentioned, and, on the other hand, allow an assessment of two important risk factors associated with this activity (work postures and loads handling), two additional methodologies were also selected: the Revised NIOSH Lifting Equation and the Rapid Entire Body Assessment (REBA). In all the performed approaches, the tasks of palletizing at lower levels were identified as the ones that most penalize workers in what regards the risk of development of WMSD. All methodologies identified levels of risk that require an immediate or short-term ergonomic intervention, aiming at ensuring the safety and health of workers performing such activity. The implementation of measures designed to eliminate or minimize the risk may involve the allocation of significant human and material resources that is increasingly necessary to manage efficiently. Taking into account the complexity and variability of the developed tasks, it is recommended that such a decision can be preceded by a new study using more accurate risk assessment methodologies, such as those that use monitoring tools.

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Dissertação de mestrado integrado em Engenharia Civil

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This study examines physical activity patterns among women, from pre-pregnancy to the second trimester of pregnancy, and the relationship between physical activity status based on physical activity guidelines and health-related quality of life (HRQoL) and depression over pregnancy. 56 healthy pregnant women self reported physical activity, HRQoL and depression at 10-15 and 19-24 weeks of pregnancy and physical activity before pregnancy. Whereas vigorous leisure physical activity decreased after conception, moderate leisure physical activity and work related physical activity remained stable over time. The prevalence of recommended physical activity was 39.3% and 12.5% in the 1st and 2nd trimesters of pregnancy respectively, and 14.3% pre-pregnancy. From the 1st to the 2nd pregnancy trimester, most physical HRQoL dimensions scores decreased and only mental component increased, independently of physical activity status. No changes in mean depression scores were observed. These data suggest that physical activity patterns change with pregnancy and that physical and mental components are differentially affected by pregnancy course, independently of physical activity status.

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Abstract : The term "muscle disuse" is often used to refer collectively to reductions in neuromuscular activity as observed with sedentary lifestyles, reduced weight bearing, cancer, chronic obstructive pulmonary disease, chronic heart failure, spinal cord injury, sarcopenia or exposure to microgravity (spaceflight). Muscle disuse atrophy, caused by accelerated proteolysis, is predominantly due to the activation of the ATP-dependent ubiquitin (Ub) proteasome pathway. The current advances in understanding the molecular factors contributing to the Ub-dependent proteolysis process have been made mostly in rodent models of human disease and denervation with few investigations performed directly in humans. Recently, in mice, the genes Atrogin-1 and MuRF1 have been designated as primary candidates in the control of muscle atrophy. Additionally, the decreased activity of the Akt/GSK-3ß and Akt/mTOR pathways has been associated with a reduction in protein synthesis and contributing to skeletal muscle atrophy. Therefore, it is now commonly accepted that skeletal muscle atrophy is the result of a decreased protein synthesis concomitant with an increase in protein degradation (Glass 2003). Atrogin-1 and MuRF1 are genes expressed exclusively in muscle. In mice, their expression has been shown to be directly correlated with the severity of atrophy. KO-mice experiments showed a major protection against atrophy when either of these genes were deleted. Skeletal muscle hypertrophy is an important function in normal postnatal development and in the adaptive response to exercise. It has been shown, in vitro, that the activation of phosphatidylinositol 3-kinase (PI-3K), by insulin growth factor 1 (IGF-1), stimulates myotubes hypertrophy by activating the downstream pathways, Akt/GSK-3ß and Akt/mTOR. It has also been demonstrated in mice, in vivo, that activation of these signalling pathways causes muscle hypertrophy. Moreover, the latter were recently proposed to also reduce muscle atrophy by inhibiting the FKHR mediated transcription of several muscle atrophy genes; Atrogin-1 and MuRF1. Therefore, these targets present new avenues for developing further the understanding of the molecular mechanisms involved in both skeletal muscle atrophy and hypertrophy. The present study proposed to investigate the regulation of the Akt/GSK-3ß and Akt/mTOR signalling pathways, as well as the expression levels of the "atrogenes", Atrogin-1 and MuRF1, in four human models of skeletal muscle atrophy. In the first study, we measured the regulation of the Akt signalling pathway after 8 weeks of both hypertrophy stimulating resistance training and atrophy stimulation de-training. As expected following resistance training, muscle hypertrophy and an increase in the phosphorylation status of the different members of the Akt pathway was observed. This was paralleled by a concomitant decrease in FOXO1 nuclear protein content. Surprisingly, exercise training also induced an increase in the, expression of the atrophy genes and proteins involved in the ATP-dependant ubiquitin-proteasome system. On the opposite, following the de-training period a muscle atrophy, relative to the post-training muscle size, was measured. At the same time, the phosphorylation levels of Akt and GSK-3ß were reduced while the amount of FOXO1 in the nucleus increased. After the atrophy phase, there was also a reduction in Atrogin-1 and MuRF1 contents. In this study, we demonstrate for the first time in healthy human skeletal muscle, that the regulation of Akt and its downstream targets GSK-3ß, mTOR and FOXO1 are associated with both thé skeletal muscle hypertrophy and atrophy processes. Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease characterized by the loss of both upper and lower motor neurons, which leads to severe muscle weakness and atrophy. All measurements were performed in biopsies from 22 ALS patients and 16 healthy controls. ALS patients displayed an increase in Atrogin-1 mRNA and protein content which was associated with a decrease in Akt activity. However there was no difference in the mRNA and phospho-protein content of FOXO1, FOXO3a, p70S6K and GSK-3ß. The transcriptional regulation of human Atrogin-1 may be controlled by an Akt-mediated transcription factor other than FKHR or via an other signalling pathway. Chronic complete spinal cord injury (SCI) is associated with severe muscle atrophy which is linked to co-morbidity factors such as diabetes, obesity, lipid disorders and cardiovascular diseases. Molecular mechanisms associated with chronic complete SCI-related muscle atrophy are not well understood. The aim of the present study was to determine if there was an increase in catabolic signalling targets such as Atrogin-1, MuRF1, FOXO and myostatin, and decreases in anabolic signalling targets such as IGF, Akt, GSK-3ß, mTOR, 4E-BP1 and p-70S6K in chronic complete SCI patients. All measurements were performed in biopsies taken from 8 complete chronic SCI patients and 7 age matched healthy controls. In SCI patients when compared with controls, there was a significant reduction in mRNA levels of Atrogin1, MuRF1 and Myostatin. Protein levels for Atrogin-1, FOX01 and FOX03a were also reduced. IGF-1 and both phosphorylated GSK-3ß and 4E-BP1 were decreased; the latter two in an Akt and mTOR independent manner, respectively. Reductions in Atrogin-1, MuRF1, FOXO and myostatin suggest the existence of an internal mechanism aimed at reducing further loss of muscle proteins during chronic SCI. The downregulation of signalling proteins regulating anabolism such as IGF, GSK3ß and 4E-BP1 would reduce the ability to increase protein synthesis rates in this chronic state of muscle wasting. The molecular mechanisms controlling age-related skeletal muscle loss in humans are poorly understood. The present study aimed to investigate the regulation of several genes and proteins involved in the activation of key signalling pathways promoting muscle hypertrophy such as GH/STAT5/IGF, IGF/Akt/GSK-3ß/4E-BP1 and muscle atrophy such as TNFα/SOCS3 and Akt/FOXO/Atrogin-1 or MuRF1 in muscle biopsies from 13 young and 16 elderly men. In the older, as compared with the young subjects, TNFα and SOCS-3 were increased while growth hormone receptor protein (GHR) and IGF-1 mRNA were both decreased. Akt protein levels were increased however no change in phosphorylated Akt content was observed. GSK-3ß phosphorylation levels were increased while 4E-BP1 was not changed. Nuclear FKHR and FKHRL1 protein levels were decreased, with no changes in their atrophy target genes, Atrogin-1 and MuRF1. Myostatin mRNA and protein levels were significantly elevated. Human sarcopenia may be linked to a reduction in the activity or sensitivity of anabolic signalling proteins such as GHR, IGF and Akt. TNFα, SOCS-3 and myostatin are potential candidates influencing this anabolic perturbation. In conclusion our results support those obtained in rodent or ín vitro models, and demonstrate Akt plays a pivotal role in the control of muscle mass in humans. However, the Akt phosphorylation status was dependant upon the model of muscle atrophy as Akt phosphorylation was reduced in all atrophy models except for SCI. Additionally, the activity pattern of the downstream targets of Akt appears to be different upon the various human models. It seems that under particular conditions such as spinal cord injury or sarcopenia, .the regulation of GSK-3ß, 4eBP1 and p70S6K might be independent of Akt suggesting alternative signalling pathways in the control of these the anabolic response in human skeletal muscle. The regulation of Atrogin-1 and MuRF1 in some of our studies has been shown to be also independent of the well-described Akt/FOXO signalling pathway suggesting that other transcription factors may regulate human Atrogin-1 and MuRF1. These four different models of skeletal muscle atrophy and hypertrophy have brought a better understanding concerning the molecular mechanisms controlling skeletal muscle mass in humans.

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PURPOSE: In Burkina Faso, gold ore is one of the main sources of income for an important part of the active population. Artisan gold miners use mercury in the extraction, a toxic metal whose human health risks are well known. The aim of the present study was to assess mercury exposure as well as to understand the exposure determinants of gold miners in Burkinabe small-scale mines.METHODS: The examined gold miners' population on the different selected gold mining sites was composed by persons who were directly and indirectly related to gold mining activities. But measurement of urinary mercury was performed on workers most susceptible to be exposed to mercury. Thus, occupational exposure to mercury was evaluated among ninety-three workers belonging to eight different gold mining sites spread in six regions of Burkina Faso. Among others, work-related exposure determinants were taken into account for each person during urine sampling as for example amalgamating or heating mercury. All participants were medically examined by a local medical team in order to identify possible symptoms related to the toxic effect of mercury.RESULTS: Mercury levels were high, showing that 69% of the measurements exceeded the ACGIH (American Conference of Industrial Hygienists) biological exposure indice (BEI) of 35 µg per g of creatinine (µg/g-Cr) (prior to shift) while 16% even exceeded 350 µg/g-Cr. Basically, unspecific but also specific symptoms related to mercury toxicity could be underlined among the persons who were directly related to gold mining activities. Only one-third among the studied subpopulation reported about less than three symptoms possibly associated to mercury exposure and nearly half of them suffered from at least five of these symptoms. Ore washers were more involved in the direct handling of mercury while gold dealers in the final gold recovery activities. These differences may explain the overexposure observed in gold dealers and indicate that the refining process is the major source of exposure.CONCLUSIONS: This study attests that mercury exposure still is an issue of concern. North-South collaborations should encourage knowledge exchange between developing and developed countries, for a cleaner artisanal gold mining process and thus for reducing human health and environmental hazards due to mercury use.