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1.
J Phys Chem Lett ; 15(17): 4711-4720, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38657124

RESUMO

We present a comprehensive scale-bridging characterization approach for supported catalytically active liquid metal solutions (SCALMS) which combines lab-based X-ray microscopy, nano X-ray computed tomography (nano-CT), and correlative analytical transmission electron microscopy. SCALMS catalysts consist of low-melting alloy particles and have demonstrated high catalytic activity, selectivity, and long-term stability in propane dehydrogenation (PDH). We established an identical-location nano-CT workflow which allows us to reveal site-specific changes of Ga-Pt SCALMS before and after PDH. These observations are complemented by analytical transmission electron microscopy investigations providing information on the structure, chemical composition, and phase distribution of individual SCALMS particles. Key findings of this combined microscopic approach include (i) structural evolution of the SCALMS particles' GaOx shell, (ii) Pt segregation toward the oxide shell leading to the formation of Ga-Pt intermetallic phases, and (iii) cracking of the oxide shell accompanied by the release of liquid Ga-Pt toward the porous support.

2.
Ecotoxicol Environ Saf ; 238: 113581, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35525113

RESUMO

The abundance and persistence of plastic nanoparticles in aquatic habitats are considered a threat to marine and freshwater biota. However, the risk assessment of plastic particles is complicated due to various factors that need to be considered, including composition, size and environmental abundance. This study investigated the behavioural response of a key river species, Gammarus roeseli, to dietary exposure of plain biodegradable and non-biodegradable plastic as well as to natural small micro- and nanoparticles. Mortality, feeding, swimming velocity and energy assimilation endpoints were examined by considering four particles sizes ranging from 30 to 1000 nm in two concentrations. Contrary to our expectations, neither decreasing size nor increasing abundance of each tested particle impacted any of the examined endpoints. Likewise, dietary exposition with biodegradable plain polylactide did not induce other or stronger effects than non-biodegradable plain polystyrene or natural silica micro- and nanoparticles, as all three particle types did not lead to adverse effects on G. roeseli. These findings also suggest that the functional role of Gammarus roeseli as a shredder is not impaired due to particle occurrence within the exposure range of this study.


Assuntos
Anfípodes , Nanopartículas , Poluentes Químicos da Água , Animais , Exposição Dietética , Comportamento Alimentar , Nanopartículas/toxicidade , Plásticos , Poliésteres , Poliestirenos/toxicidade , Dióxido de Silício , Poluentes Químicos da Água/toxicidade
3.
J Chem Phys ; 152(18): 184102, 2020 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-32414274

RESUMO

Specialized computational chemistry packages have permanently reshaped the landscape of chemical and materials science by providing tools to support and guide experimental efforts and for the prediction of atomistic and electronic properties. In this regard, electronic structure packages have played a special role by using first-principle-driven methodologies to model complex chemical and materials processes. Over the past few decades, the rapid development of computing technologies and the tremendous increase in computational power have offered a unique chance to study complex transformations using sophisticated and predictive many-body techniques that describe correlated behavior of electrons in molecular and condensed phase systems at different levels of theory. In enabling these simulations, novel parallel algorithms have been able to take advantage of computational resources to address the polynomial scaling of electronic structure methods. In this paper, we briefly review the NWChem computational chemistry suite, including its history, design principles, parallel tools, current capabilities, outreach, and outlook.

4.
Toxicol In Vitro ; 58: 215-223, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30928694

RESUMO

Biopersistent pro-inflammatory fibers are suspected human carcinogens. Cytotoxicity and transcription of pro- and anti-inflammatory mediators of different fibers were investigated in functional relationship to chemotaxis in vitro as a model for fiber-induced inflammation of the lung. We challenged NR8383 rat macrophages with multi-walled carbon nanotubes (MWCNT) and various asbestos fibers. The resulting cell supernatants were than studied using the Particle-induced Cell Migration Assay (PICMA) and cytotoxicity was determined using the LDH test. Expression of inflammatory mediators was analyzed with qPCR and verified by ELISA. Chrysotile A and the rigid, needle-shaped NM-401 caused the strongest cytotoxic effects and the largest number of migrated cells. In contrast, the MWCNT NM-400, NM-402, and NM403 were apparently non-cytotoxic but induced pronounced cell migration showing a very steep dose response. However, the strength of cell migration and cytotoxicity of the asbestos fibers were correlated. The expression profile of inflammatory mediators was comparable, although cytotoxicity of the MWCNT NM-401 and NM-403 differed strongly. Induction of the corresponding proteins was confirmed for CCL2, CCL3, CXCL1, CXCL3, IL1RA (IL1RN), CSF1, GDF15 and TNFa. Chrysotile A and NM-401 induced much stronger chemotaxis than the non-fibrous particles reported in our previous study. Cytotoxic and chemotactic effects correspond to the induction of inflammatory mediators.


Assuntos
Amianto/toxicidade , Movimento Celular/efeitos dos fármacos , Mediadores da Inflamação/metabolismo , Macrófagos/efeitos dos fármacos , Nanotubos de Carbono/toxicidade , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Humanos , Macrófagos/fisiologia , Ratos
5.
Nanotoxicology ; 10(10): 1492-1502, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27615202

RESUMO

The inhalation of particles and their exposure to the bronchi and alveoli constitute a major public health risk. Chemical as well as particle-related properties are important factors for the biological response but are difficult to separate from each other. Barium sulfate is a completely inert chemical compound, therefore it is ideally suited to separate these two factors. The biological response of rat alveolar macrophages (NR8383) was analyzed after exposure to barium sulfate particles with three different diameters (40 nm, 270 nm, and 1.3 µm, respectively) for 24 h in vitro (particle concentrations from 12.5 to 200 µg mL-1). The particles were colloidally stabilized as well as fluorescently-labeled by carboxymethylcellulose, conjugated with 6-aminofluorescein. All kinds of barium sulfate particles were efficiently taken up by NR8383 cells and found inside endo-lysosomes, but never in the cell nucleus. Neither an inflammatory nor a cytotoxic response was detected by the ability of dHL-60 and NR8383 cells to migrate towards a chemotactic gradient (conditioned media of NR8383 cells) and by the release of inflammatory mediators (CCL2, TNF-α, IL-6). The particles neither caused apoptosis (up to 200 µg mL-1) nor necrosis (up to 100 µg mL-1). As only adverse reaction, necrosis was found at a concentration of 200 µg mL-1 of the largest barium sulfate particles (1.3 µm). Barium sulfate particles are ideally suited as bioinert control to study size-dependent effects such as uptake mechanisms of intracellular distributions of pure particles, especially in nanotoxicology.


Assuntos
Sulfato de Bário/toxicidade , Quimiotaxia/efeitos dos fármacos , Macrófagos Alveolares/efeitos dos fármacos , Nanopartículas/toxicidade , Animais , Ensaios de Migração de Macrófagos , Células Cultivadas , Citometria de Fluxo , Interleucina-6/imunologia , Pulmão/efeitos dos fármacos , Macrófagos Alveolares/imunologia , Macrófagos Alveolares/metabolismo , Microscopia Confocal , Tamanho da Partícula , Ratos , Padrões de Referência , Propriedades de Superfície , Fator de Necrose Tumoral alfa/imunologia
6.
Contact Dermatitis ; 75(5): 303-307, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27356947

RESUMO

BACKGROUND: Hereditary factors may influence individual susceptibility to contact allergy. OBJECTIVES: To investigate genetic variants with impacts on early inflammatory reactions and T cell functions that possibly increase the risk of contact allergy. PATIENTS AND METHODS: Three hundred and seventy two patients undergoing patch testing were recruited from the Information Network of Departments of Dermatology (IVDK). Of these, 133 were monosensitized and 239 were polysensitized, defined as reacting to three or more unrelated sensitizers. Within the polysensitized individuals, a subgroup with at least one particularly strong patch test reaction (strong reactors; n = 194) was considered. Three hundred and forty-seven blood bank donors served as controls. Fifteen genetic variants in 13 genes were analysed. RESULTS: The homozygous variant CXCL11 AA genotype (rs6817952) was significantly more frequent among polysensitized patients (10 of 239 = 4.2%; p = 0.0048; odds ratio 7.49; 95%CI: 1.7-36.1) than among monosensitized patients (2.2%) and in the control group (0.6%). None of the remaining genetic variants investigated were characterized by similarly strong associations. However, the significance was lost after correction for multiple comparisons. CONCLUSIONS: The homozygous variant CXCL11 genotype is associated with an increased risk of contact allergy. To confirm this exploratory finding, further independent studies are needed.


Assuntos
Quimiocina CXCL11/genética , Dermatite Alérgica de Contato/genética , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Citocinas/genética , Feminino , Predisposição Genética para Doença , Homozigoto , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Testes do Emplastro , Polimorfismo de Nucleotídeo Único , Adulto Jovem
7.
Arch Toxicol ; 90(6): 1471-9, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26126632

RESUMO

High particle emissions and strong mutagenic effects were observed after combustion of vegetable oil in diesel engines. This study tested the hypothesis that these results are affected by the amount of unsaturated or polyunsaturated fatty acids of vegetable oils. Four different vegetable oils (coconut oil, CO; linseed oil, LO; palm tree oil, PO; and rapeseed oil, RO) and common diesel fuel (DF) were combusted in a heavy-duty diesel engine. The exhausts were investigated for particle emissions and mutagenic effects in direct comparison with emissions of DF. The engine was operated using the European Stationary Cycle. Particle masses were measured gravimetrically while mutagenicity was determined using the bacterial reverse mutation assay with tester strains TA98 and TA100. Combustion of LO caused the largest amount of total particulate matter (TPM). In comparison with DF, it particularly raised the soluble organic fraction (SOF). RO presented second highest TPM and SOF, followed by CO and PO, which were scarcely above DF. RO revealed the highest number of mutations of the vegetable oils closely followed by LO. PO was less mutagenic, but still induced stronger effects than DF. While TPM and SOF were strongly correlated with the content of polyunsaturated fatty acids in the vegetable oils, mutagenicity had a significant correlation with the amount of total unsaturated fatty acids. This study supports the hypothesis that numbers of double bounds in unsaturated fatty acids of vegetable oils combusted in diesel engines influence the amount of emitted particles and the mutagenicity of the exhaust. Further investigations have to elucidate the causal relationship.


Assuntos
Biocombustíveis/análise , Ácidos Graxos Insaturados/química , Gasolina/análise , Mutagênicos/toxicidade , Material Particulado/toxicidade , Óleos de Plantas/química , Emissões de Veículos/toxicidade , Testes de Mutagenicidade , Mutagênicos/análise , Material Particulado/análise , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/genética , Emissões de Veículos/análise
8.
Toxicol In Vitro ; 29(5): 997-1005, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25896209

RESUMO

Inflammation is a decisive pathophysiologic mechanism of particle toxicity and accumulation of neutrophils in the lung is believed to be a crucial step in this process. This study describes an in vitro model for investigations of the chemotactic attraction of neutrophils in response to particles using permanent cell lines. We challenged NR8383 rat macrophages with particles that were characterized concerning chemical nature, crystallinity, and size distribution in the dry state and in the culture medium. The cell supernatants were used to investigate migration of differentiated human leukemia cells (dHL-60 cells). The dose range for the tests was determined using an impedance-based Real-Time Cell Analyzer. The challenge of NR8383 cells with 32-96 µg cm(-2) coarse and nanosized particles resulted in cell supernatants which induced strong and dose-dependent migration of dHL-60 cells. Quartz caused the strongest effects - exceeding the positive control "fetal calf serum" (FCS) several-fold, followed by silica, rutile, carbon black, and anatase. BaSO4 served as inert control and induced no cell migration. Particles caused NR8383 cells to secrete chemotactic compounds. The assay clearly distinguished between the particles of different inflammatory potential in a highly reproducible way. Specificity of the test is suggested by negative results with BaSO4.


Assuntos
Ensaios de Migração Celular , Nanopartículas/toxicidade , Animais , Sulfato de Bário/toxicidade , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Células HL-60 , Humanos , Inflamação , Macrófagos/efeitos dos fármacos , Macrófagos/fisiologia , Microscopia Eletrônica de Varredura , Nanopartículas/ultraestrutura , Neutrófilos/efeitos dos fármacos , Neutrófilos/fisiologia , Ratos , Dióxido de Silício/toxicidade , Fuligem/toxicidade , Titânio/toxicidade
9.
Bone Marrow Transplant ; 49(9): 1223-30, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25046214

RESUMO

Little is known of health-relevant behaviour among long-term survivors of haematological disorders treated with haematopoietic SCT. This comparative cross-sectional multicentre study aimed (1) to explore the prevalence of selected behaviours in this group and (2) to compare them with those of the general population. Self-reported data of 376 survivors (mean age: 50.4 (s.d. = 12.8); median 7 years postallogeneic SCT (interquartile range (IQR) = 8.9; range 1-33) were compared with controls derived from the Swiss Health Survey 2007 by propensity score matching. Survivors were more physically inactive (26.8% vs 12.5%; P ⩽ 0.001) and consumed fewer portions of vegetables (⩾ 3 pieces: 10% vs 21.6%; P < 0.001), fruits (⩾ 3 pieces: 6.5% vs 10.6%; P < 0.001) and fish (31.2% vs 60.9% weekly fish dish; P < 0.001). More survivors consumed dairy products daily (92.5% vs 62.9%; P < 0.001), used sun protection regularly (94.5% vs 85.3%, P < 0.001) and had received influenza vaccinations in the past year (58.4% vs 21.5%; P < 0.001); fewer survivors smoked (13.4% vs 35.4%; P < 0.001). Survivors' weekly alcohol consumption was lower (median 1.5 servings (IQR 4) vs median 4.5 (IQR 10.3); P < 0.001). Of those taking immunosuppressants, 65.7% were non-adherent. Similar to the general population, survivors experience problems executing several health-enhancing behaviours, warranting corrective interventions.


Assuntos
Transplante de Células-Tronco Hematopoéticas/psicologia , Transplante Homólogo/psicologia , Estudos de Casos e Controles , Estudos Transversais , Feminino , Comportamentos Relacionados com a Saúde , Transplante de Células-Tronco Hematopoéticas/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Sobreviventes , Condicionamento Pré-Transplante/métodos , Transplante Homólogo/métodos
10.
Biomed Res Int ; 2014: 592434, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24511538

RESUMO

Amylenes are unsaturated hydrocarbons (C5H10), such as 1-pentene, 2-pentene, 2-methyl-but-1-en (3-methyl-1-butene), 2-methyl-but-2-en (isopentene), and 3-methyl-but-1-en. We investigated bacterial mutagenicity of 1-pentene, 2-pentene, and 3-methyl-but-1-en in the Ames test. 2-Pentene was investigated as racemate and as pure diastereomers. We included the methyltransferase deficient Salmonella Typhimurium strain YG7108 and the application of a gas-tight preincubation to reduce the risk of false negative results. 1,2-Epoxypentane which may arise from 1-pentene was used as positive control. None of the investigated amylenes showed mutagenic effects, whereas 1,2-epoxypentane was mutagenic exceeding 100 µ g per plate. An exceptional high reverse mutation in the negative control plates in the experiments with 1,2-epoxypentane was obviously caused by evaporation into the incubator which was shown by placing the control plates in a separate apparatus. No differences were seen upon use of YG7108 and its parent strain TA1535. In conclusion, 1,2-epoxypentane is most probably not a substrate of the deleted bacterial methyltransferases. The comparison of the bacterial mutagenicity of the investigated amylenes and 1,2-epoxipentane suggests that epoxidation of amylenes in the S9-mix does not proceed effectively or is counterbalanced by detoxifying reactions. The assessment of mutagenic effects of short chained aliphatic epoxides can be underestimated due to the evaporation of these compounds.


Assuntos
Alcenos/toxicidade , Compostos de Epóxi/toxicidade , Mutagênicos/toxicidade , Mutação/efeitos dos fármacos , Salmonella typhimurium/efeitos dos fármacos
11.
Micron ; 51: 60-9, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23891259

RESUMO

Otoliths of modern bony fishes are massive polycrystalline structures consisting mainly of calcium carbonate (primarily aragonite), and 1-10% organic residuals. Unlike other biomineralisates like shells, teeth and bones, they are not optimized for mechanical loads but serve the senses of hearing and balance in the inner ear. We examined internal structural variation of otoliths through microstructural and texture analyses. Our study applied the electron backscattered diffraction technique (EBSD) to whole sections of saccular otoliths on cave- and surface-dwelling fish. Application of high spatial resolution EBSD on otoliths of the livebearing fish Poecilia mexicana allowed for an investigation of crystal orientation despite the small size (<150 nm) of aragonite crystallites. Crystallites at the rims of otoliths had a higher structural organization than those situated near the center, where no dominant orientation pattern was discernible. Moreover, the medial (sulcal) face of otoliths, which makes contact with the sensory epithelium, was more structured than the lateral (antisulcal) face.


Assuntos
Membrana dos Otólitos/ultraestrutura , Poecilia/fisiologia , Animais , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão
12.
Environ Sci Technol ; 47(11): 6038-46, 2013 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-23647143

RESUMO

Research on renewable fuels has to assess possible adverse health and ecological risks as well as conflicts with global food supply. This investigation compares the two newly developed biogenic diesel fuels hydrotreated vegetable oil (HVO) and jatropha methyl ester (JME) with fossil diesel fuel (DF) and rapeseed methyl ester (RME) for their emissions and bacterial mutagenic effects. Samples of exhaust constituents were compared after combustion in a Euro III heavy duty diesel engine. Regulated emissions were analyzed as well as particle size and number distributions, carbonyls, polycyclic aromatic hydrocarbons (PAHs), and bacterial mutagenicity of the exhausts. Combustion of RME and JME resulted in lower particulate matter (PM) compared to DF and HVO. Particle numbers were about 1 order of magnitude lower for RME and JME. However, nitrogen oxides (NOX) of RME and JME exceeded the Euro III limit value of 5.0 g/kWh, while HVO combustion produced the smallest amount of NOX. RME produced the lowest emissions of hydrocarbons (HC) and carbon monoxide (CO) followed by JME. Formaldehyde, acetaldehyde, acrolein, and several other carbonyls were found in the emissions of all investigated fuels. PAH emissions and mutagenicity of the exhausts were generally low, with HVO revealing the smallest number of mutations and lowest PAH emissions. Each fuel showed certain advantages or disadvantages. As proven before, both biodiesel fuels produced increased NOX emissions compared to DF. HVO showed significant toxicological advantages over all other fuels. Since jatropha oil is nonedible and grows in arid regions, JME may help to avoid conflicts with the food supply worldwide. Hydrogenated jatropha oil should now be investigated if it combines the benefits of both new fuels.


Assuntos
Biocombustíveis/toxicidade , Jatropha , Óleos de Plantas/química , Emissões de Veículos/análise , Monóxido de Carbono/análise , Ésteres/química , Hidrogenação , Testes de Mutagenicidade/métodos , Óxidos de Nitrogênio/análise , Tamanho da Partícula , Material Particulado , Hidrocarbonetos Policíclicos Aromáticos/análise , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/genética , Emissões de Veículos/toxicidade
13.
Crit Rev Toxicol ; 42(9): 732-50, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22871157

RESUMO

Fuels from renewable resources have gained worldwide interest due to limited fossil oil sources and the possible reduction of atmospheric greenhouse gas. One of these fuels is so called biodiesel produced from vegetable oil by transesterification into fatty acid methyl esters (FAME). To get a first insight into changes of health hazards from diesel engine emissions (DEE) by use of biodiesel scientific studies were reviewed which compared the combustion of FAME with common diesel fuel (DF) for legally regulated and non-regulated emissions as well as for toxic effects. A total number of 62 publications on chemical analyses of DEE and 18 toxicological in vitro studies were identified meeting the criteria. In addition, a very small number of human studies and animal experiments were available. In most studies, combustion of biodiesel reduces legally regulated emissions of carbon monoxide, hydrocarbons, and particulate matter. Nitrogen oxides are regularly increased. Among the non-regulated emissions aldehydes are increased, while polycyclic aromatic hydrocarbons are lowered. Most biological in vitro assays show a stronger cytotoxicity of biodiesel exhaust and the animal experiments reveal stronger irritant effects. Both findings are possibly caused by the higher content of nitrogen oxides and aldehydes in biodiesel exhaust. The lower content of PAH is reflected by a weaker mutagenicity compared to DF exhaust. However, recent studies show a very low mutagenicity of DF exhaust as well, probably caused by elimination of sulfur in present DF qualities and the use of new technology diesel engines. Combustion of vegetable oil (VO) in common diesel engines causes a strongly enhanced mutagenicity of the exhaust despite nearly unchanged regulated emissions. The newly developed fuel "hydrotreated vegetable oil" (HVO) seems to be promising. HVO has physical and chemical advantages compared to FAME. Preliminary results show lower regulated and non-regulated emissions and a decreased mutagenicity.


Assuntos
Biocombustíveis/toxicidade , Gasolina/toxicidade , Petróleo/toxicidade , Emissões de Veículos/toxicidade , Poluentes Atmosféricos/análise , Animais , Biocombustíveis/análise , Dano ao DNA/efeitos dos fármacos , Gasolina/análise , Humanos , Hidrocarbonetos/análise , Modelos Animais , Mutagênicos , Óxidos de Nitrogênio/análise , Material Particulado/análise , Material Particulado/toxicidade , Petróleo/análise , Óleos de Plantas/química , Hidrocarbonetos Policíclicos Aromáticos/análise , Medição de Risco , Emissões de Veículos/análise
14.
Radiologe ; 52(7): 656-60, 2012 Jul.
Artigo em Alemão | MEDLINE | ID: mdl-22660510

RESUMO

A 63-year-old male patient presented with retrobulbar pressure which had been present for 1 year. Contrast-enhanced computed tomography (CT) and magnetic resonance imaging (MRI) revealed symmetrical retrobulbar, perivascular and retroperitoneal infiltration of soft tissue and also showed cardiac involvement. In combination with the histological findings displaying infiltration by foamy histiocytes, Erdheim-Chester disease was diagnosed.


Assuntos
Doença de Erdheim-Chester/diagnóstico , Imageamento por Ressonância Magnética , Tomografia Computadorizada por Raios X , Humanos , Masculino , Pessoa de Meia-Idade
15.
Environ Sci Technol ; 46(11): 6417-24, 2012 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-22587467

RESUMO

Concerns about adverse health effects of diesel engine emissions prompted strong efforts to minimize this hazard, including exhaust treatment by diesel oxidation catalysts (DOC). The effectiveness of such measures is usually assessed by the analysis of the legally regulated exhaust components. In recent years additional analytical and toxicological tests were included in the test panel with the aim to fill possible analytical gaps, for example, mutagenic potency of polycyclic aromatic hydrocarbons (PAH) and their nitrated derivatives (nPAH). This investigation focuses on the effect of a DOC on health hazards from combustion of four different fuels: rapeseed methyl ester (RME), common mineral diesel fuel (DF), SHELL V-Power Diesel (V-Power), and ARAL Ultimate Diesel containing 5% RME (B5ULT). We applied the European Stationary Cycle (ESC) to a 6.4 L turbo-charged heavy load engine fulfilling the EURO III standard. The engine was operated with and without DOC. Besides regulated emissions we measured particle size and number distributions, determined the soluble and solid fractions of the particles and characterized the bacterial mutagenicity in the gas phase and the particles of the exhaust. The effectiveness of the DOC differed strongly in regard to the different exhaust constituents: Total hydrocarbons were reduced up to 90% and carbon monoxide up to 98%, whereas nitrogen oxides (NO(X)) remained almost unaffected. Total particle mass (TPM) was reduced by 50% with DOC in common petrol diesel fuel and by 30% in the other fuels. This effect was mainly due to a reduction of the soluble organic particle fraction. The DOC caused an increase of the water-soluble fraction in the exhaust of RME, V-Power, and B5ULT, as well as a pronounced increase of nitrate in all exhausts. A high proportion of ultrafine particles (10-30 nm) in RME exhaust could be ascribed to vaporizable particles. Mutagenicity of the exhaust was low compared to previous investigations. The DOC reduced mutagenic effects most effectively in the gas phase. Mutagenicity of particle extracts was less efficiently diminished. No significant differences of mutagenic effects were observed among the tested fuels. In conclusion, the benefits of the DOC concern regulated emissions except NO(X) as well as nonregulated emissions such as the mutagenicity of the exhaust. The reduction of mutagenicity was particularly observed in the condensates of the gas phase. This is probably due to better accessibility of gaseous mutagenic compounds during the passage of the DOC in contrast to the particle-bound mutagens. Concerning the particulate emissions DOC especially decreased ultrafine particles.


Assuntos
Gases/química , Gasolina/análise , Testes de Mutagenicidade/métodos , Material Particulado/toxicidade , Transição de Fase , Emissões de Veículos/análise , Emissões de Veículos/toxicidade , Bactérias/genética , Catálise , Cloretos/análise , Cromatografia , Gasolina/toxicidade , Mutagênese/efeitos dos fármacos , Mutação/genética , Nitratos/análise , Oxirredução , Material Particulado/química , Solventes , Sulfatos/análise
16.
Dtsch Med Wochenschr ; 136(50): 2589-93, 2011 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-22160951

RESUMO

BACKGROUND: To assess the diagnostic value of an additionally acquired plain abdominal radiograph in supine position. MATERIALS AND METHODS: Two experienced radiologists evaluated retrospectively 2148 consecutive patients having plain abdominal radiographs acquired in a tertiary care center. There were 1385 patients having an erect view and 763 patients with a left lateral decubitus view. All patients had a second examination in supine position. First the radiographs in erect or decubitus view were evaluated regarding the presence and details of pathological changes. After 4 weeks all radiographs including the supine view were evaluated again. Next to pathological changes the additional value of the supine projection was assessed. The results were compared and the additional diagnostic value using the supine view was noted. RESULTS: We evaluated 2148 patients having a plain abdominal radiograph (1325 men, 823 women, mean 58.9 years, range 15-96 years). The average age within the group acquired with left decubitus view was 61.1 years, while patients having an erect view had a mean age of 57.0 years. For the first evaluation we found pathological changes in 10.5% (decubitus view: 13.1%, erect view 9.5%; p = 0.01). The most frequent diagnosis was ileus (7.7%) followed by abdominal free air (2.4%). The results were confirmed during the second reading in 99.2%. In 3.5% (decubitus view 5.8%, erect view 2.2%) more anatomical structures were depicted considering the supine projection and the decubitus/erect projections. The anatomical information was in no case relevant for the diagnosis. CONCLUSION: Having the information of an supine view additionally to an decubitus/erect view increases the depiction of anatomical structures up to 5.8%. Nevertheless there was no additional diagnostic relevant information based on the supine view.


Assuntos
Intensificação de Imagem Radiográfica/métodos , Radiografia Abdominal/métodos , Decúbito Dorsal , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade , Adulto Jovem
18.
J Eur Acad Dermatol Venereol ; 21(4): 456-61, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17373970

RESUMO

OBJECTIVE: This study examines the extent of stigmatization experienced by vitiligo patients considering the visibility of the lesions. METHODS: 363 vitiligo patients were assessed using the Experience with Skin Complaints (QES), Adjustment to Chronic Skin Disorders (ASC), and Sense of Coherence (SOC) questionnaires. Out of the total patients group two representative samples with 52 patients each were identified comparable for age, gender, and the duration of the skin disease, the first with visible and the second with invisible lesions. RESULTS: Data indicate a significant negative correlation between the QES dimensions, except for 'Composure', and between coping scales with sense of coherence withstanding. The 'visible lesions' group scored higher compared to the 'invisible lesions' group on the two QES scales 'Self-Esteem' and 'Refusal', i.e., patients with visible lesions experienced a higher level of stigmatization. CONCLUSION: This study provides new information which supports the notion that the stigmatization experience of vitiligo patients is psychologically relevant.


Assuntos
Adaptação Psicológica , Atitude Frente a Saúde , Estereotipagem , Vitiligo/psicologia , Adolescente , Adulto , Ansiedade/psicologia , Depressão/psicologia , Feminino , Humanos , Masculino , Qualidade de Vida , Rejeição em Psicologia , Autoimagem , Autoavaliação (Psicologia) , Pele/patologia , Ajustamento Social , Comportamento Social , Desejabilidade Social , Vitiligo/patologia
19.
Arch Dermatol Res ; 298(8): 371-9, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17072629

RESUMO

Variations in the melanocortin-1 receptor (MC1R) and in the glutathione-S transferase genes mu1 (GSTM1) and theta 1 (GSTT1) have been reported to influence UV sensitivity and melanoma risk. MC1R is one of the major genes that determine skin pigmentation because the melanocortin-1 receptor regulates eumelanin synthesis. GSTT1 and GSTM1 are enzymes expressed in the skin that detoxify products of oxidative stress reactions caused by UV irradiation. In this study variations in the MC1R, GSTM1 and T1 genes were analyzed in 347 healthy subjects and 322 patients with cutaneous malignant melanoma by direct cycle sequencing, RFLP and multiplex PCR. Important phenotypic characteristics of the study participants were obtained to assess whether genetic associations occurred independently of phenotypic risk factors for melanoma. We found an association of the MC1R D84E and R151C polymorphisms with melanoma (odds ratios for carriage of the rare allele 4.96, 95% CI [1.06-23.13], P = 0.032, and 1.69, 95% CI [1.12-2.55], P = 0.013, respectively). Melanoma risk increased with the number of variant MC1R alleles carried by an individual (P = 0.003). In a multivariate model, however, only the D84E polymorphism influenced melanoma risk independently of the risk factors fair skin type, high nevus count and high age (P = 0.047). There was no effect of homozygous GST M1 or T1 deletions on melanoma risk. In contrast to previous data, there was no evidence that GSTM1 deficiency influences melanoma risk in the subgroup of individuals with red or blond hair.


Assuntos
Glutationa Transferase/genética , Melanoma/genética , Polimorfismo de Nucleotídeo Único/genética , Receptor Tipo 1 de Melanocortina/genética , Neoplasias Cutâneas/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Cor de Olho , Feminino , Deleção de Genes , Predisposição Genética para Doença , Cor de Cabelo , Humanos , Masculino , Pessoa de Meia-Idade , Nevo/patologia , Razão de Chances , Fatores de Risco
20.
Int J Clin Pharmacol Ther ; 44(8): 364-74, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16961167

RESUMO

INTRODUCTION: There is an established role of clinical risk factors such as arterial hypertension and smoking in causing cardiovascular morbidity and diabetic nephropathy (DNP). Genetic factors increase the risk for DNP. To examine the genetic risk, we initiated a case-control study with predefined follow-up examinations. We describe the study design and baseline characteristics under special consideration of comedication, and give preliminary results of the 4-year follow-up. METHODS: We enrolled all 477 patients with DNP receiving maintenance hemodialysis in 30 centers in Southern Germany between August 1999 and January 2000. As controls, we enrolled all 482 diabetes mellitus type 2 patients without urinary microalbuminuria in two examinations on consecutive days and without other signs of renal disease in a large diabetes clinic from September 2000 to September 2001. Follow-up examinations are performed 4 and 6 years after inclusion by questionnaire and telephone interview to determine mortality and new morbidity. Controls progressing to novel DNP at follow-up, as defined by semiquantitative dipstick urinary albumin/creatinine ratio > 30 mg/g, are defined as cases in the study's nested case control component. RESULTS: At study inclusion in cases and controls, respectively, mean age was 67.3 +/- 8.2 and 58.1 +/- 11.2 years and duration of diabetes mellitus was 15.6 +/- 9.6 (at dialysis initiation) and 11.0 +/- 8.6 years. 328 controls (of which 25 had died and 14 did not perform urinalysis) were subjected to follow-up at 4 years, at a mean of 3.5 +/- 0.8 years after inclusion. 51.2% (n = 148) of living controls remained normalbuminuric, 33.9% (n = 98) had microor macroalbuminuria, and in 14.9% (n = 43) the dipstick test was inconclusive. There was no significant difference in progression to micro- or macroalbuminuria between controls treated with ACE or AT-2 inhibitors at baseline or not. Renal function as estimated by the abbreviated MDRD formula declined from 86.8 +/- 21.0 to 82.5 +/- 22.3 ml/min/1.73 m2 (p < 0.001). The decline was significant in patients on ACE or AT-2 inhibitors at baseline and not in patients without such medication at baseline. DISCUSSION: GENDIAN is a large case-control study designed to evaluate clinical and genetic determinants of DNP and other complications of long-standing diabetes mellitus type 2. We observed an association of ACE or AT-2 inhibitor therapy with cardiovascular comorbidity and a significant decline in renal function after a 4-year follow-up.


Assuntos
Albuminúria/prevenção & controle , Bloqueadores do Receptor Tipo 1 de Angiotensina II/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Nefropatias Diabéticas/terapia , Fatores Etários , Idoso , Albuminúria/epidemiologia , Albuminúria/mortalidade , Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacologia , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Estudos de Casos e Controles , Comorbidade , Creatinina/urina , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/genética , Nefropatias Diabéticas/epidemiologia , Nefropatias Diabéticas/genética , Progressão da Doença , Quimioterapia Combinada , Feminino , Seguimentos , Predisposição Genética para Doença/genética , Alemanha/epidemiologia , Humanos , Masculino , Diálise Renal , Fatores Sexuais , Inquéritos e Questionários , Taxa de Sobrevida
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