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1.
Philos Trans A Math Phys Eng Sci ; 380(2216): 20210062, 2022 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-34923847

RESUMO

We review two algorithmic advances that bring us closer to reliable quantum simulations of model systems in high-energy physics and beyond on noisy intermediate-scale quantum (NISQ) devices. The first method is the dimensional expressivity analysis of quantum circuits, which allows for constructing minimal but maximally expressive quantum circuits. The second method is an efficient mitigation of readout errors on quantum devices. Both methods can lead to significant improvements in quantum simulations, e.g. when variational quantum eigensolvers are used. This article is part of the theme issue 'Quantum technologies in particle physics'.

2.
Front Cell Dev Biol ; 9: 774751, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34869374

RESUMO

Amyotrophic lateral sclerosis (ALS) is a rapidly progressive disease leading to degeneration of motor neurons (MNs). Epigenetic modification of gene expression is increasingly recognized as potential disease mechanism. In the present study we generated motor neurons from induced pluripotent stem cells from ALS patients carrying a mutation in the fused in sarcoma gene (FUS) and analyzed expression and promoter methylation of the FUS gene and expression of DNA methyltransferases (DNMTs) compared to healthy control cell lines. While mutant FUS neural progenitor cells (NPCs) did not show a difference in FUS and DNMT expression compared to healthy controls, differentiated mutant FUS motor neurons showed significantly lower FUS expression, higher DNMT expression and higher methylation of the proximal FUS gene promoter. Immunofluorescence revealed perceived proximity of cytoplasmic FUS aggregates in ALS MNs together with 5-methylcytosin (5-mC). Targeting disturbed methylation in ALS may therefore restore transcriptional alterations and represent a novel therapeutic strategy.

3.
Arch Toxicol ; 94(1): 1-58, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31848664

RESUMO

Advances in the biological sciences have led to an ongoing paradigm shift in toxicity testing based on expanded application of high-throughput in vitro screening and in silico methods to assess potential health risks of environmental agents. This review examines progress on the vision for toxicity testing elaborated by the US National Research Council (NRC) during the decade that has passed since the 2007 NRC report on Toxicity Testing in the 21st Century (TT21C). Concomitant advances in exposure assessment, including computational approaches and high-throughput exposomics, are also documented. A vision for the next generation of risk science, incorporating risk assessment methodologies suitable for the analysis of new toxicological and exposure data, resulting in human exposure guidelines is described. Case study prototypes indicating how these new approaches to toxicity testing, exposure measurement, and risk assessment are beginning to be applied in practice are presented. Overall, progress on the 20-year transition plan laid out by the US NRC in 2007 has been substantial. Importantly, government agencies within the United States and internationally are beginning to incorporate the new approach methodologies envisaged in the original TT21C vision into regulatory practice. Future perspectives on the continued evolution of toxicity testing to strengthen regulatory risk assessment are provided.


Assuntos
Rotas de Resultados Adversos , Medição de Risco/métodos , Testes de Toxicidade/métodos , Animais , Carcinógenos/química , Carcinógenos/toxicidade , Biologia Computacional/métodos , Mineração de Dados , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , Ensaios de Triagem em Larga Escala , Humanos , National Academy of Sciences, U.S. , Relação Estrutura-Atividade , Testes de Toxicidade/tendências , Toxicogenética/métodos , Toxicologia/métodos , Estados Unidos
4.
Food Chem Toxicol ; 133: 110748, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31377140

RESUMO

Hexavalent chromium raises high concern because of its wide industrial applications and reported toxicity. Long-term (135 days) oral exposure of Wistar rats to chromium in the form of K2Cr2O7 (exposed group~20 mg/kg/day) led to a decrease in thymus mass and thymocytes' number and caused structural and functional changes in the lymph nodes and spleen, namely lymphoreticular hyperplasia and plasmocytic macrophage transformation. Programmed cell death was increased in both thymocytes and splenocytes and decreased in lymphocytes in the T-zones of spleen and lymph nodes. Moreover, Cr (VI) administration decreased myeloid cells' and neutrophils' number, while it increased lymphoid and erythroid cells' number in bone marrow. Cr (VI) immune system effects seem to be related to oxidative stress induction, as depicted by the increased levels of diene conjugates and malondialdehyde in the spleen and liver and by the decreased activity of catalase and superoxide dismutase in rats' erythrocytes. In addition, exposure to Cr (VI) decreased copper, nickel and iron concentrations in blood and liver, while Cr levels in blood, spleen and liver were increased, as expected. The observed changes in the series of immunological parameters studied contribute to the development of new approaches for the prevention of low level Cr exposure toxicity.


Assuntos
Cromo/toxicidade , Linfonodos/efeitos dos fármacos , Baço/efeitos dos fármacos , Timo/efeitos dos fármacos , Animais , Peso Corporal/efeitos dos fármacos , Imuno-Histoquímica , Linfonodos/metabolismo , Contagem de Linfócitos , Masculino , Tamanho do Órgão/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Ratos Wistar , Baço/metabolismo , Linfócitos T/metabolismo , Timócitos/metabolismo , Timo/metabolismo , Timo/patologia
5.
Psychooncology ; 27(1): 75-82, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28568377

RESUMO

OBJECTIVE: Psychological distress is common in cancer patients, and awareness of its indicators is essential. We aimed to assess the prevalence of psychological distress and to identify problems indicative of high distress. METHODS: We used the distress thermometer (DT) and its 34-item problem list to measure psychological distress in 3724 cancer patients (mean age 58 years; 57% women) across major tumor entities, enrolled in an epidemiological multicenter study. To identify distress-related problems, we conducted monothetic analyses. RESULTS: We found high levels of psychological distress (DT ≥ 5) in 52% of patients. The most prevalent problems were fatigue (56%), sleep problems (51%), and problems getting around (47%). Sadness, fatigue, and sleep problems were most strongly associated with the presence of other problems. High distress was present in 81.4% of patients reporting all 3 of these problems (DT M = 6.4). When analyzing only the subset of physical problems, fatigue, problems getting around, and indigestion showed the strongest association with the remaining problems and 76.3% of patients with all 3 problems were highly distressed (DT M = 6.1). CONCLUSIONS: Our results show a high prevalence of psychological distress in cancer patients, as well as a set of problems that indicate the likely presence of other problems and high distress and can help clinicians identify distressed patients even if no routine distress screening is available.


Assuntos
Depressão/diagnóstico , Fadiga/diagnóstico , Programas de Rastreamento/métodos , Neoplasias/psicologia , Estresse Psicológico/diagnóstico , Adulto , Idoso , Depressão/epidemiologia , Depressão/psicologia , Emoções , Fadiga/epidemiologia , Fadiga/etiologia , Fadiga/psicologia , Feminino , Inquéritos Epidemiológicos , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/complicações , Prevalência , Escalas de Graduação Psiquiátrica , Estresse Psicológico/epidemiologia , Estresse Psicológico/etiologia , Estresse Psicológico/psicologia
6.
Regul Toxicol Pharmacol ; 88: 157-172, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28645885

RESUMO

The Threshold Toxicological Concern (TTC) is based on the concept that in absence of experimental data reasonable assurance of safety can be given if exposure is sufficiently low. Using the REACH database the low 5th percentile of the NO(A)EL distribution, for prenatal developmental toxicity (OECD guideline 414) was determined. For rats, (434 NO(A)ELs values) for maternal toxicity, this value was 10 mg/kg-bw/day. For developmental toxicity (469 NO(A)ELs): 13 mg/kg-bw/day. For rabbits, (100 NO(A)ELs), the value for maternal toxicity was 4 mg/kg-bw/day, for developmental toxicity, (112 NO(A)EL values): 10 mg/kg-bw/day. The maternal organism may thus be slightly more sensitive than the fetus. Combining REACH- (industrial chemicals) and published BASF-data (mostly agrochemicals), 537 unique compounds with NO(A)EL values for developmental toxicity in rats and 150 in rabbits were evaluated. The low 5th percentile NO(A)EL for developmental toxicity in rats was 10 mg/kg-bw/day and 9.5 mg/kg-bw/day for rabbits. Using an assessment factor of 100, a TTC value for developmental toxicity of 100 µg/kg-bw/day for rats and 95 µg/kg-bw/day for rabbits is calculated. These values could serve as guidance whether or not to perform an animal experiment, if exposure is sufficiently low. In emergency situations this value may be useful for a first tier risk assessment.


Assuntos
Agroquímicos/toxicidade , Desenvolvimento Fetal/efeitos dos fármacos , Feto/efeitos dos fármacos , Animais , Bases de Dados Factuais , Feminino , Nível de Efeito Adverso não Observado , Coelhos , Ratos , Medição de Risco , Testes de Toxicidade
8.
Artigo em Inglês | MEDLINE | ID: mdl-27334307

RESUMO

This longitudinal study was designed to assess patients' desire for early retirement and investigate which cancer-related and psychosocial characteristics are associated with early retirement. We assessed 750 cancer patients at the beginning (t0 ) and end (t1 ) of, and 12 months after (t2 ) inpatient cancer rehabilitation. At t0 , 22% had a desire to retire early. These patients reported significantly longer sick leave periods, less favourable workplace environments, lower work ability, higher psychological distress and lower quality of life than other patients. At t2 , 12.5% of patients received temporary or permanent early retirement pensions. Of all patients with a desire for early retirement at t0 , 43% had returned to work at t2 . This subgroup had a significantly lower physical quality of life than other patients returning to work. The most influential predictors of early retirement were being on sick leave (OR = 6.50, 95% CI = 1.97-21.47) and a desire for early retirement (OR = 5.61, 95% CI = 2.73-11.52). Inverse predictors of early retirement were cancer remission (OR = 0.23, 95% CI = 0.10-0.53), perceived productivity (OR = 0.38, 95% CI = 0.18-0.83), work satisfaction (OR = 0.36, 95% CI = 0.17-0.77) and mental quality of life (OR = 0.94, 95% CI = 0.91-0.98). This underlines the need for cancer-specific multi-professional rehabilitation and occupational therapy programmes.


Assuntos
Neoplasias/reabilitação , Qualidade de Vida , Aposentadoria/estatística & dados numéricos , Retorno ao Trabalho/estatística & dados numéricos , Estresse Psicológico/epidemiologia , Local de Trabalho , Adulto , Fatores Etários , Atitude , Eficiência , Feminino , Humanos , Satisfação no Emprego , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Neoplasias/psicologia , Razão de Chances , Pensões , Aposentadoria/psicologia , Retorno ao Trabalho/psicologia , Fatores de Risco , Licença Médica/estatística & dados numéricos , Estresse Psicológico/psicologia , Adulto Jovem
9.
Eur J Cancer ; 72: 46-53, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28024266

RESUMO

BACKGROUND: Depression is a common co-morbidity of cancer that has a detrimental effect on quality of life, treatment adherence and potentially survival. We conducted an epidemiological multi-center study including a population-based random comparison sample and estimated the prevalence of depressive symptoms by cancer site, thereby identifying cancer patients with the highest prevalence of depression. PATIENTS AND METHODS: We included 4020 adult cancer inpatients and outpatients from five distinct regions across Germany in a proportional stratified random sample based on the nationwide cancer incidence and a comparison group consisting of 5018 participants. Both groups reported depressive symptoms by filling in the Patient Health Questionnaire (PHQ-9). In multivariate analyses adjusted for age and sex, we calculated the odds of being depressed. RESULTS: Out of 5818 eligible patients, 69% participated (51% women, mean age = 58 years). We estimated that one in four cancer patients (24%) is depressed (PHQ-9 ≥ 10). The odds of being depressed among cancer patients were more than five times higher than in the general population (OR, 5.4; 95% CI, 4.6-6.2). Patients with pancreatic (M = 8.0, SD = 5.0), thyroid (M = 7.8, SD = 6.3) and brain tumours (M = 7.6, SD = 4.9) showed the highest prevalence, whereas patients with prostate cancer (M = 4.3, SD = 3.8) and malignant melanoma (M = 5.3, SD = 4.3) had the lowest levels of depressive symptoms. CONCLUSION: Our results help clinicians identify cancer patients in need of psychosocial support when navigating in the growing survivor population.


Assuntos
Transtorno Depressivo/epidemiologia , Neoplasias/psicologia , Adolescente , Adulto , Idoso , Transtorno Depressivo/etiologia , Feminino , Alemanha/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prevalência , Escalas de Graduação Psiquiátrica , Adulto Jovem
10.
Arch Toxicol ; 90(11): 2725-2743, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26647301

RESUMO

Several shortcomings of current Parkinson's disease (PD) models limit progress in identification of environmental contributions to disease pathogenesis. The conditionally immortalized cell line LUHMES promises to make human dopaminergic neuronal cultures more easily available, but these cells are difficult to culture for extended periods of time. We overcame this problem by culturing them in 3D with minor medium modifications. The 3D neuronal aggregates allowed penetration by small molecules and sufficient oxygen and nutrient supply for survival of the innermost cells. Using confocal microscopy, gene expression, and flow cytometry, we characterized the 3D model and observed a highly reproducible differentiation process. Visualization and quantification of neurites in aggregates was achieved by adding 2 % red fluorescent protein-transfected LUHMES cells. The mitochondrial toxicants and established experimental PD agents, rotenone and MPP+, perturbed genes involved in one-carbon metabolism and transsulfuration pathways (ASS1, CTH, and SHTM2) as in 2D cultures. We showed, for the first time in LUHMES, down-regulation of mir-7, a miRNA known to target alpha-synuclein and to be involved in PD. This was observed as early as 12 h after rotenone exposure, when pro-apoptotic mir-16 and rotenone-sensitive mir-210 were not yet significantly perturbed. Finally, washout experiments demonstrated that withdrawal of rotenone led to counter-regulation of mir-7 and ASS1, CTH, and SHTM2 genes. This suggests a possible role of these genes in direct cellular response to the toxicant, and the model appears to be suitable to address the processes of resilience and recovery in neurotoxicology and Parkinson's disease in future studies.


Assuntos
Antiparkinsonianos/farmacologia , Neurônios Dopaminérgicos/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos/métodos , Fármacos Neuroprotetores/farmacologia , Neurotoxinas/toxicidade , Testes de Toxicidade Aguda/métodos , Testes de Toxicidade Crônica/métodos , Agregação Celular , Técnicas de Cultura de Células , Diferenciação Celular , Linhagem Celular Transformada , Sobrevivência Celular/efeitos dos fármacos , Neurônios Dopaminérgicos/citologia , Neurônios Dopaminérgicos/metabolismo , Resistência a Medicamentos , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Imageamento Tridimensional , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Microscopia Confocal , Microscopia de Fluorescência , Proteínas do Tecido Nervoso/agonistas , Proteínas do Tecido Nervoso/antagonistas & inibidores , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Neuritos/efeitos dos fármacos , Neuritos/metabolismo , Proteínas Recombinantes/metabolismo
11.
Nervenarzt ; 86(3): 258, 260-2, 264-5, 2015 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-25676922

RESUMO

Given the increasing incidence of cancer and improved diagnostics and cancer treatments, the number of cancer patients in industrialized nations is increasing worldwide. Multimodal treatment regimens, which contribute to a tumor-free survival or extend patients life expectancy can, however, alone or in combination increase the risk of physical and psychosocial long-term problems or late complications. For many patients cancer has become a chronic disease and is associated with significant physical and psychosocial problems that affect the quality of life in the medium and longer-term perspective. Common problems of cancer patients in the longer course of the disease include chronic and post-cancer pain, cancer-specific fatigue, psychosocial distress and impairment in self-management and activities of daily living, work participation and quality of life. Current developments with respect to both curative and palliative oncological care have various implications for health services research in psycho-oncology. These questions relate to issues of care needs, service provision and the appropriateness of care, issues of development, implementation and scientific evaluation of patient-centered and affordable support programs for different groups of cancer patients with different supportive care needs, issues of access and utilization of supportive care services, as well as questions of appropriate outcome criteria of health services research.


Assuntos
Pesquisa sobre Serviços de Saúde/organização & administração , Oncologia/organização & administração , Transtornos Mentais/terapia , Neoplasias/terapia , Psicologia/organização & administração , Alemanha , Humanos , Transtornos Mentais/psicologia , Neoplasias/psicologia , Cuidados Paliativos/organização & administração , Equipe de Assistência ao Paciente/organização & administração
12.
Cell Death Dis ; 5: e1222, 2014 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-24810058

RESUMO

Assessment of the network of toxicity pathways by Omics technologies and bioinformatic data processing paves the road toward a new toxicology for the twenty-first century. Especially, the upstream network of responses, taking place in toxicant-treated cells before a point of no return is reached, is still little explored. We studied the effects of the model neurotoxicant 1-methyl-4-phenylpyridinium (MPP(+)) by a combined metabolomics (mass spectrometry) and transcriptomics (microarrays and deep sequencing) approach to provide unbiased data on earliest cellular adaptations to stress. Neural precursor cells (LUHMES) were differentiated to homogeneous cultures of fully postmitotic human dopaminergic neurons, and then exposed to the mitochondrial respiratory chain inhibitor MPP(+) (5 µM). At 18-24 h after treatment, intracellular ATP and mitochondrial integrity were still close to control levels, but pronounced transcriptome and metabolome changes were seen. Data on altered glucose flux, depletion of phosphocreatine and oxidative stress (e.g., methionine sulfoxide formation) confirmed the validity of the approach. New findings were related to nuclear paraspeckle depletion, as well as an early activation of branches of the transsulfuration pathway to increase glutathione. Bioinformatic analysis of our data identified the transcription factor ATF-4 as an upstream regulator of early responses. Findings on this signaling pathway and on adaptive increases of glutathione production were confirmed biochemically. Metabolic and transcriptional profiling contributed complementary information on multiple primary and secondary changes that contribute to the cellular response to MPP(+). Thus, combined 'Omics' analysis is a new unbiased approach to unravel earliest metabolic changes, whose balance decides on the final cell fate.


Assuntos
1-Metil-4-fenilpiridínio/toxicidade , Neurônios Dopaminérgicos/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Células-Tronco Neurais/efeitos dos fármacos , Síndromes Neurotóxicas/etiologia , Transcrição Gênica/efeitos dos fármacos , Fator 4 Ativador da Transcrição/genética , Fator 4 Ativador da Transcrição/metabolismo , Adaptação Fisiológica , Trifosfato de Adenosina/metabolismo , Linhagem Celular , Biologia Computacional , Neurônios Dopaminérgicos/metabolismo , Neurônios Dopaminérgicos/patologia , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica , Glucose/metabolismo , Glutationa/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Espectrometria de Massas , Metabolômica/métodos , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Células-Tronco Neurais/metabolismo , Células-Tronco Neurais/patologia , Síndromes Neurotóxicas/genética , Síndromes Neurotóxicas/metabolismo , Síndromes Neurotóxicas/patologia , Análise de Sequência com Séries de Oligonucleotídeos , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/genética , Fosfocreatina/metabolismo , Interferência de RNA , Fatores de Tempo , Transfecção
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