Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 246
Filtrar
1.
Nanoscale Adv ; 1(9): 3680-3685, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-36133532

RESUMO

MXenes are a rapidly growing family of 2D materials that exhibit a highly versatile structure and composition, allowing for significant tuning of the materials properties. These properties are, however, ultimately limited by the surface terminations, which are typically a mixture of species, including F and O that are inherent to the MXene processing. Other and robust terminations are lacking. Here, we apply high-resolution scanning transmission electron microscopy (STEM), corresponding image simulations and first-principles calculations to investigate the surface terminations on MXenes synthesized from MAX phases through Lewis acidic melts. The results show that atomic Cl terminates the synthesized MXenes, with mere residual presence of other termination species. Furthermore, in situ STEM-electron energy loss spectroscopy (EELS) heating experiments show that the Cl terminations are stable up to 750 °C. Thus, we present an attractive new termination that widely expands the MXenes' functionalization space and enables new applications.

2.
Allergy ; 73(5): 1053-1063, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29319193

RESUMO

BACKGROUND: Impaired antiviral interferon expression may be involved in asthma exacerbations commonly caused by rhinovirus infections. Allergy is a known risk factor for viral-induced asthma exacerbation, but little is known whether allergens may affect interferon responses. OBJECTIVE: Our hypothesis is that house dust mite (HDM) impairs viral stimulus-induced antiviral signalling. METHODS: Experimental asthma exacerbations were produced in vitro in human bronchial epithelial cells (HBECs) and in mice using sequential challenges with HDM and a viral infection mimic, Poly(I:C). We examined rhinovirus pattern recognition receptors (PRRs) signalling pathways and potential mechanisms of impaired interferon response. RESULTS: HBECs and mice exposed to HDM prior to Poly(I:C) exhibited a reduced antiviral response compared to Poly(I:C) alone, including reduced IFN-ß, IFN-λ, TLR3, RIG-I, MDA5, IRF-3 and IRF-7. Heat inactivation of HDM partially restored the TLR3-induced interferon response in vitro and in vivo. Our HBEC-data further showed that HDM directly affects TLR3 signalling by targeting the receptor glycosylation level. CONCLUSIONS: Direct effects of allergens such as HDM on PRRs can present as potential mechanism for defective antiviral airway responses. Accordingly, therapeutic measures targeting inhibitory effects of allergens on antiviral PRRs may find use as a strategy to boost antiviral response and ameliorate exacerbations in asthmatic patients.


Assuntos
Asma/imunologia , Interferons/biossíntese , Infecções por Picornaviridae/imunologia , Pyroglyphidae/imunologia , Receptor 3 Toll-Like/imunologia , Animais , Asma/virologia , Células Cultivadas , Células Epiteliais/imunologia , Células Epiteliais/virologia , Humanos , Hipersensibilidade/imunologia , Indutores de Interferon/imunologia , Interferons/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Infecções por Picornaviridae/complicações , Poli I-C/imunologia , Receptores de Reconhecimento de Padrão/imunologia , Rhinovirus
3.
J Nutr Health Aging ; 21(9): 1057-1064, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29083448

RESUMO

OBJECTIVES: The aim is to explore the effects of antecedent, structural and process quality indicators of nutritional care practice on meal satisfaction and screened nutritional status among older adults in residential care homes. DESIGN: Data for this Swedish cross-sectional study regarding older adults living in residential care homes were collected by i) a national questionnaire, ii) records from the quality registry Senior Alert, iii) data from an Open Comparison survey of elderly care in 2013/2014. The data represented 1154 individuals in 117 of 290 Swedish municipalities. MEASUREMENTS: Meal satisfaction (%) and adequate nutritional status, screened by the Mini Nutritional Assessment Short Form (MNA-SF), were the two outcome variables assessed through their association with population density of municipalities and residents' age, together with 12 quality indicators pertaining to structure and process domains in the Donabedian model of care. RESULTS: Meal satisfaction was associated with rural and urban municipalities, with the structure quality indicators: local food policies, private meal providers, on-site cooking, availability of clinical/community dietitians, food service dietitians, and with the process quality indicators: meal choice, satisfaction surveys, and 'meal councils'. Adequate nutritional status was positively associated with availability of clinical/community dietitians, and energy and nutrient calculated menus, and negatively associated with chilled food production systems. CONCLUSION: Municipality characteristics and structure quality indicators had the strongest associations with meal satisfaction, and quality indicators with local characteristics emerge as important for meal satisfaction. Nutritional competence appears vital for residents to be well-nourished.


Assuntos
Avaliação Nutricional , Apoio Nutricional/métodos , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Masculino , Inquéritos e Questionários
6.
Leukemia ; 30(9): 1853-60, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27133821

RESUMO

Dasatinib (DAS) and interferon-α have antileukemic and immunostimulatory effects and induce deep responses in chronic myeloid leukemia (CML). We assigned 40 newly diagnosed chronic-phase CML patients to receive DAS 100 mg o.d. followed by addition of pegylated interferon-α2b (PegIFN) after 3 months (M3). The starting dose of PegIFN was 15 µg/week and it increased to 25 µg/week at M6 until M15. The combination was well tolerated with manageable toxicity. Of the patients, 84% remained on PegIFN at M12 and 91% (DAS) and 73% (PegIFN) of assigned dose was given. Only one patient had a pleural effusion during first year, and three more during the second year. After introduction of PegIFN we observed a steep increase in response rates. Major molecular response was achieved in 10%, 57%, 84% and 89% of patients at M3, M6, M12 and M18, respectively. At M12, MR(4) was achieved by 46% and MR(4.5) by 27% of patients. No patients progressed to advanced phase. In conclusion, the combination treatment appeared safe with very promising efficacy. A randomized comparison of DAS±PegIFN is warranted.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/toxicidade , Dasatinibe/administração & dosagem , Interferon-alfa/administração & dosagem , Leucemia Mieloide de Fase Crônica/tratamento farmacológico , Polietilenoglicóis/administração & dosagem , Adolescente , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Feminino , Humanos , Interferon alfa-2 , Masculino , Pessoa de Meia-Idade , Derrame Pleural , Proteínas Recombinantes/administração & dosagem , Indução de Remissão , Resultado do Tratamento , Adulto Jovem
7.
Nanoscale ; 8(13): 7056-67, 2016 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-26960813

RESUMO

Tin oxide is considered to be one of the most promising semiconductor oxide materials for use as a gas sensor. However, a simple route for the controllable build-up of nanostructured, sufficiently pure and hierarchical SnO2 structures for gas sensor applications is still a challenge. In the current work, an aqueous SnO2 nanoparticulate precursor sol, which is free of organic contaminants and sorbed ions and is fully stable over time, was prepared in a highly reproducible manner from an alkoxide Sn(OR)4 just by mixing it with a large excess of pure neutral water. The precursor is formed as a separate liquid phase. The structure and purity of the precursor is revealed using XRD, SAXS, EXAFS, HRTEM imaging, FTIR, and XRF analysis. An unconventional approach for the estimation of the particle size based on the quantification of the Sn-Sn contacts in the structure was developed using EXAFS spectroscopy and verified using HRTEM. To construct sensors with a hierarchical 3D structure, we employed an unusual emulsification technique not involving any additives or surfactants, using simply the extraction of the liquid phase, water, with the help of dry butanol under ambient conditions. The originally generated crystalline but yet highly reactive nanoparticles form relatively uniform spheres through self-assembly and solidify instantly. The spheres floating in butanol were left to deposit on the surface of quartz plates bearing sputtered gold electrodes, producing ready-for-use gas sensors in the form of ca. 50 µm thick sphere-based-films. The films were dried for 24 h and calcined at 300 °C in air before use. The gas sensitivity of the structures was tested in the temperature range of 150-400 °C. The materials showed a very quickly emerging and reversible (20-30 times) increase in electrical conductivity as a response to exposure to air containing 100 ppm of H2 or CO and short (10 s) recovery times when the gas flow was stopped.

8.
J Intern Med ; 278(4): 335-53, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26123389

RESUMO

In response to the 2009-2010 influenza A(H1N1)pdm09 pandemic, a mass vaccination programme with the AS03-adjuvanted influenza A(H1N1) vaccine Pandemrix was initiated in Sweden. Unexpectedly, there were a number of narcolepsy cases amongst vaccinated children and adolescents reported. In this review, we summarize the results of a joint cross-disciplinary national research effort to investigate the adverse reaction signal from the spontaneous reporting system and to better understand possible causative mechanisms. A three- to fourfold increased risk of narcolepsy in vaccinated children and adolescents was verified by epidemiological studies. Of importance, no risk increase was observed for the other neurological and autoimmune diseases studied. Genetic studies confirmed the association with the allele HLA-DQB1*06:02, which is known to be related to sporadic narcolepsy. Furthermore, a number of studies using cellular and molecular experimental models investigated possible links between influenza vaccination and narcolepsy. Serum analysis, using a peptide microarray platform, showed that individuals who received Pandemrix exhibited a different epitope reactivity pattern to neuraminidase and haemagglutinin, as compared to individuals who were infected with H1N1. Patients with narcolepsy were also found to have increased levels of interferon-gamma production in response to streptococcus-associated antigens. The chain of patient-related events and the study results emerging over time were subjected to intense nationwide media attention. The importance of transparent communication and collaboration with patient representatives to maintain public trust in vaccination programmes is also discussed in the review. Organizational challenges due to this unexpected event delayed the initiation of some of the research projects, still the main objectives of this joint, cross-disciplinary research effort were reached, and important insights were acquired for future, similar situations in which a fast and effective task force may be required to evaluate vaccination-related adverse events.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Vacinas contra Influenza/efeitos adversos , Influenza Humana/prevenção & controle , Narcolepsia/etiologia , Vacinação/efeitos adversos , Adolescente , Criança , Epitopos/imunologia , Hemaglutininas/imunologia , Humanos , Imuno-Histoquímica , Interferon gama/biossíntese , Relações Interprofissionais , Narcolepsia/genética , Narcolepsia/imunologia , Neuraminidase/imunologia , Fragmentos de Peptídeos/biossíntese , Pesquisa , Streptococcus/imunologia , Suécia
10.
Med Oncol ; 31(8): 66, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24965535

RESUMO

Even in the tyrosine kinase inhibitor era, allogeneic hematopoietic stem cell transplantation (HSCT) is regarded as standard care for adult Philadelphia (Ph) positive acute lymphoblastic leukemia (ALL). In this retrospective national study, we have reviewed the outcome after HSCT in Sweden for adult Ph-positive ALL between 2000 and 2009. In total, 51 patients with median age 42 (range 20-66) years underwent HSCT. Mainly allogeneic HSCT was performed (24 related donor, 24 unrelated donor and one cord blood), and only two patients were treated with an autologous HSCT. The 5-year OS was 51 (37-64) %. The probabilities of morphological relapse and non-relapse mortality (NRM) at 5 years were 36 (23-49) and 18 (9-29) %, respectively. For the allogeneic transplanted, the 5-year OS was for patients <40 years 70 (50-90) % and for patients ≥40 years 34 (16-52) %, p = 0.002. The 5-year probability of NRM was for patients <40 years 10 (2-28) % compared to 25 (11-42) % for patients ≥40 years (p = 0.04). Patients with chronic graft-versus-host disease (GVHD) had a 5-year morphological relapse probability of 20 (6-40) % compared to 59 (35-77) % for patients without chronic GVHD (p = 0.03). Age ≥40 years and the absence of chronic GVHD were confirmed as independent negative prognostic factors for relapse and non-relapse mortality in a multivariate analysis although the impact of chronic GVHD was significant only in the older age cohort.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Adulto , Idoso , Autoenxertos , Benzamidas/uso terapêutico , Feminino , Proteínas de Fusão bcr-abl/genética , Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Mesilato de Imatinib , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/epidemiologia , Piperazinas/uso terapêutico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidade , Inibidores de Proteínas Quinases/uso terapêutico , Pirimidinas/uso terapêutico , Taxa de Sobrevida , Suécia , Transplante Homólogo/efeitos adversos , Resultado do Tratamento , Adulto Jovem
12.
J Intern Med ; 275(2): 172-90, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24134219

RESUMO

OBJECTIVES: To investigate the association between vaccination with Pandemrix and risk of selected neurological and immune-related diseases including narcolepsy. DESIGN: Population-based prospective cohort study using data from regional vaccination registries and national health registries. SETTING: Seven healthcare regions in Sweden comprising 61% of the Swedish population. SUBJECTS: Study population of 3,347,467 vaccinated and 2,497,572 nonvaccinated individuals (vaccination coverage ≈ 60%) followed between 2009 and 2011 for 6.9 million person-years after exposure and 6.0 million person-years without exposure. MAIN OUTCOME MEASURE AND ANALYSIS: First recorded diagnosis of neurological and immune-related diseases. Relative risks [hazard ratios (HRs) with 95% confidence intervals (CIs)] assessed using Cox regression, adjusted for covariates. RESULTS: For all selected neurological and immune-related outcomes under study, other than allergic vaccine reactions (for which we verified an expected increase in risk) and narcolepsy, HRs were close to 1.0 and always below 1.3. We observed a three-fold increased risk of a diagnosis of narcolepsy (HR: 2.92, 95% CI: 1.78-4.79; that is, four additional cases per 100,000 person-years) in individuals ≤ 20 years of age at vaccination and a two-fold increase (HR: 2.18, 95% CI: 1.00-4.75) amongst young adults between 21 and 30 years of age. The excess risk declined successively with increasing age at vaccination; no increase in risk was seen after 40 years of age. CONCLUSIONS: For a large number of selected neurological and immune-related diseases, we could neither confirm any causal association with Pandemrix nor refute entirely a small excess risk. We confirmed an increased risk for a diagnosis of narcolepsy in individuals ≤ 20 years of age and observed a trend towards an increased risk also amongst young adults between 21 and 30 years.


Assuntos
Doenças do Sistema Imunitário/induzido quimicamente , Vacinas contra Influenza/efeitos adversos , Narcolepsia/induzido quimicamente , Doenças do Sistema Nervoso/induzido quimicamente , Vacinação/efeitos adversos , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Doenças Autoimunes do Sistema Nervoso/induzido quimicamente , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Vacinas contra Influenza/administração & dosagem , Masculino , Pessoa de Meia-Idade , Razão de Chances , Modelos de Riscos Proporcionais , Estudos Prospectivos , Sistema de Registros , Risco , Suécia/epidemiologia
13.
Allergy ; 69(3): 348-58, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24283976

RESUMO

BACKGROUND: Rhinovirus infection or dsRNA stimulation increased thymic stromal lymphopoietin (TSLP), an upstream pro-allergic cytokine, in asthmatic bronchial epithelial cells. We hypothesized that dsRNA challenges superimposed on established experimental allergic asthma constitute a useful exacerbation model. We further hypothesized that TSLP is induced at dsRNA- and rhinoviral infection-induced exacerbations. METHODS: Allergic mice were challenged with OVA followed by three daily intranasal challenges with dsRNA or saline. Bronchoalveolar lavage fluid (BALF) was analysed for total protein, lactate dehydrogenase (LDH), CXCL1/KC, CCL2/MCP-1 and differential cell counts. Lung tissue histology, neutrophils and TSLP, TNF-α, IFN-ß and IFN-λ mRNA were examined. Alternatively, allergen-challenged mice received intranasal rhinovirus-(RV)-1B followed by lung TSLP immunostaining. RESULTS: In mice with allergic airway inflammation, dsRNA challenges caused a significant exacerbation increasing lung tissue inflammation score and tissue neutrophilia. Bronchoalveolar lavage fluid neutrophils, total protein, LDH, CXCL1/KC and CCL2/MCP-1 were also increased (P < 0.01), and so were lung tissue expressions of TNF-α, IFN-λ and TSLP (P < 0.01), but IFN-ß was not increased. TSLP, IFN-λ and LDH were not increased by allergen or dsRNA challenges alone, but increased exclusively at exacerbations. RV1B infection-induced exacerbation also increased lung tissue TSLP (P < 0.05). CONCLUSIONS: dsRNA-induced exacerbation in mice with experimental asthma involved general inflammation, cytokines and interferons, in agreement with previous observations in exacerbating human asthma. Additionally, both dsRNA and RV1B infection increased lung TSLP exclusively at exacerbations. Our data suggest that dsRNA challenges superimposed on allergic inflammation are suited for pharmacological studies of asthma exacerbations including the regulation of lung tissue TSLP, TNF-α, IFN-ß and IFN-λ.


Assuntos
Asma/genética , Asma/imunologia , Citocinas/genética , Pulmão/imunologia , Pulmão/metabolismo , Neutrófilos/imunologia , RNA de Cadeia Dupla/imunologia , Rhinovirus/imunologia , Administração Intranasal , Animais , Modelos Animais de Doenças , Expressão Gênica , Interferon gama/genética , Pulmão/patologia , Camundongos , Ovalbumina/imunologia , RNA de Cadeia Dupla/administração & dosagem , Fator de Necrose Tumoral alfa/genética , Linfopoietina do Estroma do Timo
14.
Environ Pollut ; 180: 19-26, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23727563

RESUMO

Polychlorinated dibenzo-p-dioxins and polychlorinated dibenzo-p-furans (PCDD/Fs) were analysed in soil from a Swedish sawmill site where chlorophenols (CPs) had been used more than 40 years ago. The most contaminated area at the site was the preservation subarea where the PCDD/F WHO2005-TEQ level was 3450 times higher than the current Swedish guideline value of 200 ng TEQ/kg soil for land for industrial use. It was also shown that a fire which destroyed the sawmill might have affected the congener distribution at the concerned areas. To get a broader picture of the contamination both GIS (spatial interpolation analysis) and multivariate data analysis (PCA) were applied to visualize and compare PCDD/F levels as well as congener distributions at different areas at the site. It is shown that GIS and PCA are powerful tools in decisions on future investigations, risk assessments and remediation of contaminated sites.


Assuntos
Benzofuranos/análise , Monitoramento Ambiental/métodos , Poluição Ambiental/estatística & dados numéricos , Dibenzodioxinas Policloradas/análogos & derivados , Polímeros/análise , Poluentes do Solo/análise , Sistemas de Informação Geográfica , Indústrias , Dibenzodioxinas Policloradas/análise , Análise de Componente Principal , Solo/química , Suécia
15.
Waste Manag ; 29(2): 506-12, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18571397

RESUMO

In order to manage municipal solid waste incineration (MSWI) bottom ash safely, risk assessments, including the prediction of leaching under different field conditions, are necessary. In this study, the influence of salt or dissolved organic matter (DOM) in the influent on metal leaching from MSWI bottom ash was investigated in a column experiment. The presence of salt (0.1M NaCl) resulted in a small increase of As leaching, whereas no impact on leachate concentration was found when lakewater DOM (35.1mg/l dissolved organic carbon) was added. Most of the added DOM was retained within the material. Further, X-ray spectroscopy revealed that Cu(II) was the dominating form of Cu and that it probably occurred as a CuO-type mineral. The Cu(2+) activity in the MSWI bottom ash leachate was most likely determined by the dissolution of CuO together with the formation of Cu-DOM complexes and possibly also by adsorption to (hydr)oxide minerals. The addition of lake DOM in the influent resulted in lower saturation indices for CuO in the leachates, which may be due to slow CuO dissolution kinetics in combination with strong Cu-DOM complexation.


Assuntos
Incineração , Metais/química , Compostos Orgânicos/química , Cloreto de Sódio/química , Poluentes Ambientais , Solubilidade
16.
Pharmacoepidemiol Drug Saf ; 17(5): 475-84, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18322905

RESUMO

PURPOSE: Only randomized clinical trials (RCTs) are deemed suitable to determine causality, as epidemiological studies are considered not 'robust'. The objective of this study was to evaluate whether causality should remain the only consideration with drug toxicity signals. Cyclooxygenase-2 (Cox-2) inhibitors provided an example. METHODS: Our study population included patients aged 40+ years prescribed Cox-2 inhibitors in the General Practice Research Database (GPRD) (N = 150 000). We estimated the risks of upper gastrointestinal (GI) events and myocardial infarction (MI). Attributable risks were estimated using simulation methodology based on various hypothetical scenarios. RESULTS: The risk-benefit profile was strongly related to the rate of GI events. With a RCT incidence, the GI benefits would exceed MI risks. With a 'real-life' GI incidence, the benefits did not exceed the risks substantially. The onset and offset of drug effects also predicted the magnitude of both risks and benefits. If risks and benefits occurred in different sub-groups, the risk-benefit profile varied substantially. Also, it was found that any restriction of use to patients at high risk of drug toxicity may not improve the risk-benefit profile when this restriction affected patients who would benefit most. CONCLUSIONS: We conclude that rigid classification of evidence is not appropriate in the monitoring of risks and benefits and all valid study evidence--not only that derived from a RCT--needs to be included. The first priority should be to consider the potential impact of a drug toxicity signal.


Assuntos
Inibidores de Ciclo-Oxigenase 2/efeitos adversos , Métodos Epidemiológicos , Seleção de Pacientes , Adulto , Idoso , Causalidade , Celecoxib , Simulação por Computador , Bases de Dados Factuais , Feminino , Gastroenteropatias/induzido quimicamente , Gastroenteropatias/epidemiologia , Humanos , Lactonas/efeitos adversos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/induzido quimicamente , Infarto do Miocárdio/epidemiologia , Pirazóis/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto , Medição de Risco/métodos , Sulfonamidas/efeitos adversos , Sulfonas/efeitos adversos
17.
J Hazard Mater ; 158(2-3): 401-9, 2008 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-18329799

RESUMO

Chromium(III), copper(II), zinc(II), cadmium(II), mercury(II) and lead(II) cations are among the most common heavy metal pollutants in industrial waste waters. In our continued work on cost effective wastewater heavy metal removal agents and methods using local material, this study examines the interactions of chromium(III), copper(II), zinc(II), cadmium(II), mercury(II) and lead(II) cations with natural mixed clay minerals from Tundulu in Malawi using extended X-ray absorption fine structure (EXAFS) spectroscopy. The mixed clays were previously characterised and found to contain illite, low ordered kaolinite, mixed layer minerals and the non-clay mineral carbonate fluoroapatite with a mean pH(PZC) of 9.63. The EXAFS analyses provided qualitative evidence that oxygen atoms occupy the first coordination shells in all the studied central atoms. The metal species on the clay mineral surfaces seem to be adsorbates and/or precipitates of hydrolysis products. Chromium(III) forms a polynuclear hydrolysis complex on the mineral surface with Cr-O bond and Cr...Cr distances of 2.00 and 3.03 A, respectively, which is indicative of a chain structure with edge sharing CrO(6) octahedra. Copper(II) is bound to phosphate groups on the surface at low pH and has a first shell of coordinated oxygen atoms with Jahn-Teller distortion as revealed by different Cu-O bonds of 1.96 A for the equatorial ones, at 2.30 and 2.65 A for the axial oxygens, and a Cu-P distance at 3.29 A is distinguished as well. Upon treatment at neutral pH copper(I) oxide seems to be the main precipitation product on the clay surface. At neutral pH zinc(II) forms also polynuclear hydrolysis complexes with Zn-O bond and Zn...Zn distances of 2.01 and 3.11A, respectively, which shows the presence of edge sharing ZnO(4) tetrahedra. Cadmium(II) is adsorbed to the clay surfaces as a six-coordinated CdO(6) complex in octahedral fashion, but it is not possible to distinguish if cadmium is hydrated or partly hydrolysed. Mercury(II) is present as linear O-Hg-O units but without any observable Hg...Hg distance at high pH showing that mercury(II) is hydrolysed but not present as mercury(II) oxide. At low pH, linear O-Hg-Hg-O units are present showing that mercury(II) is reduced to mercury(I). No precise chemical environment around the lead(II) could be obtained for the lead(II) treated clays due to formation of different hydrolysis structures with multiple coordination numbers by lead(II) salts on the mixed clays.


Assuntos
Silicatos de Alumínio , Metais Pesados/química , Análise Espectral/métodos , Adsorção , Argila , Malaui , Raios X
18.
Int J Epidemiol ; 37(2): 405-13, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18263647

RESUMO

BACKGROUND: Selective cyclooxygenase-2 (Cox-2) inhibitors, developed to reduce the risk of NSAID-related gastrointestinal (GI) complications, have been associated with an increased risk of cardiovascular events. Our objective was to determine the balance of potential harm and benefit related to Cox-2 inhibitors' exposure. METHODS: The study population included patients aged 40+ years who received a prescription for Cox-2 inhibitors and were included in the General Practice Research Database. The incidence of upper GI events, myocardial infarction (MI) and stroke was estimated in this cohort. It was assumed that patients had experienced the upper GI and cardiovascular effects, as observed in clinical trials [relative rate (RR) of 0.49 for upper GI and 1.86 for MI]. Simulation methodology was used to estimate attributable risks, i.e. the difference between exposed and unexposed event probabilities. RESULTS: The study population included 155,439 Cox-2 users. The number of upper GI events prevented by Cox-2 inhibitors was 179, while the number of excess MI cases was 83 per 10,000 patients treated for 4 years. A strong association was found between extent of GI benefit and cardiovascular harm. There was a large difference in the frequency of benefit over harm in only 6% of the patients (difference of 1% or more); 23% of the patients had more harm than benefit, including those with a history of ischaemic heart disease. CONCLUSIONS: The benefit of Cox-2 inhibitors in reducing the frequency of upper GI events may be offset by their cardiovascular harm, particularly in patients with risk factors for cardiovascular disease.


Assuntos
Doenças Cardiovasculares/induzido quimicamente , Inibidores de Ciclo-Oxigenase 2/efeitos adversos , Adulto , Idoso , Anti-Inflamatórios não Esteroides/efeitos adversos , Anti-Inflamatórios não Esteroides/uso terapêutico , Estudos de Coortes , Simulação por Computador , Inibidores de Ciclo-Oxigenase 2/uso terapêutico , Bases de Dados Factuais , Europa (Continente) , Medicina de Família e Comunidade , Feminino , Gastroenteropatias/induzido quimicamente , Gastroenteropatias/prevenção & controle , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Infarto do Miocárdio/induzido quimicamente , Probabilidade , Vigilância de Produtos Comercializados/métodos , Risco , Acidente Vascular Cerebral/induzido quimicamente , Resultado do Tratamento
19.
Rev. ortop. traumatol. (Madr., Ed. impr.) ; 50(5): 382-385, sept. 2006. ilus
Artigo em Es | IBECS | ID: ibc-051200

RESUMO

Presentamos el caso de una paciente con fractura pertrocantérea del fémur y que, un año después de ser tratada con un «clavo gamma» y de evolucionar favorablemente, desarrolló una necrosis avascular de la cabeza femoral. Se discute su posible patogenia y se concluye recomendando una buena técnica de fijación quirúrgica para evitar el proceso y pensar en esta posibilidad cuando los resultados clínicos de un paciente que había experimentado un buen resultado se deterioren tardíamente


This is a case study of a patient with a intertrochanteric femoral fracture treated by gamma nailing with favourable evolution for a period of one year that subsequently developed avascular necrosis of the femoral head. The possible cause is discussed and a good surgical fixation technique is recommended to prevent this outcome. It is advisable to consider this condition as a possible explanation for the long-term deterioration of a patient with good initial postoperative clinical results


Assuntos
Feminino , Idoso , Humanos , Fixação Interna de Fraturas/efeitos adversos , Necrose da Cabeça do Fêmur/cirurgia , Complicações Pós-Operatórias/cirurgia , Pinos Ortopédicos/efeitos adversos , Necrose da Cabeça do Fêmur/etiologia
20.
Hum Reprod ; 21(5): 1237-42, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16431901

RESUMO

BACKGROUND: Several observations of the coexistence of endometriosis and cancer have been published. One study concerning endometriosis patients from 1969 to 1986 showed an overall relative cancer risk of 1.2 and relative risks for breast cancer, ovarian cancer and non-Hodgkin's lymphoma to be 1.3, 1.9 and 1.8, respectively. The aim of this study was to see whether these risk ratios stand in an extended study with longer follow-up. METHODS: Women discharged from a hospital, with a diagnosis of endometriosis from 1969 to 2000, were identified using the National Swedish Inpatient Register. Data were linked to the National Swedish Cancer Register to identify cases of cancer. Data on hysterectomies and oophorectomies were available. Standardized incidence ratios (SIR) were calculated. RESULTS: 64 492 women entered the study. First year of follow-up was excluded, leaving 3349 cases of cancer. There was no increased overall risk of cancer [SIR 1.04, 95% CI 1.00-1.07]. Elevated risks were found for ovarian cancer (SIR 1.43, 95% CI 1.19-1.71), endocrine tumours (SIR 1.36, 95% CI 1.15-1.61), non-Hodgkin's lymphoma (SIR 1.24, 95% CI 1.02-1.49) and brain tumours (SIR 1.22, 95% CI 1.04-1.41). Women with early diagnosed and long-standing endometriosis had a higher risk of ovarian cancer, with SIR of 2.01 and 2.23, respectively. The average age at endometriosis diagnosis was 39.4, indicating that there are the moderate/severe cases that are included in this study. Women who had a hysterectomy before or at the time of the endometriosis diagnosis did not show an increased risk of ovarian cancer. CONCLUSION: Women with endometriosis have an increased risk of some malignancies, particularly ovarian cancer, and the risk increases with early diagnosed or long-standing disease. Hysterectomy may have a preventive effect against ovarian cancer.


Assuntos
Endometriose/complicações , Doenças Ovarianas/complicações , Neoplasias Ovarianas/epidemiologia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Pessoa de Meia-Idade , Neoplasias/complicações , Neoplasias/epidemiologia , Neoplasias Ovarianas/complicações , Risco , Suécia/epidemiologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...