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2.
Microbiol Spectr ; 11(1): e0378922, 2023 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-36602312

RESUMEN

Neutralization assays are important for understanding and quantifying neutralizing antibody responses toward severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The SARS-CoV-2 lentivirus surrogate neutralization assay (SCLSNA) can be used in biosafety level 2 (BSL-2) laboratories and has been shown to be a reliable alternative approach to the plaque reduction neutralization test (PRNT). In this study, we optimized and validated the SCLSNA to assess its ability as a comparator and prescreening method to support the PRNT. Comparability between the PRNT and SCLSNA was determined through clinical sensitivity and specificity evaluations. Clinical sensitivity and specificity assays produced acceptable results, with 100% (95% confidence interval [CI], 94% to 100%) specificity and 100% (95% CI, 94% to 100%) sensitivity against ancestral Wuhan spike-pseudotyped lentivirus. The sensitivity and specificity against B.1.1.7 spike-pseudotyped lentivirus were 88.3% (95% CI, 77.8% to 94.2%) and 100% (95% CI, 94% to 100%), respectively. Assay precision measuring intra-assay variability produced acceptable results for high (50% PRNT [PRNT50], 1:≥640), mid (PRNT50, 1:160), and low (PRNT50, 1:40) antibody titer concentration ranges based on the PRNT50, with coefficients of variation (CVs) of 14.21%, 12.47%, and 13.28%, respectively. Intermediate precision indicated acceptable ranges for the high and mid concentrations, with CVs of 15.52% and 16.09%, respectively. However, the low concentration did not meet the acceptance criteria, with a CV of 26.42%. Acceptable ranges were found in the robustness evaluation for both intra-assay and interassay variability. In summary, the validation parameters tested met the acceptance criteria, making the SCLSNA method fit for its intended purpose, which can be used to support the PRNT. IMPORTANCE Neutralization studies play an important role in providing guidance and justification for vaccine administration and helping prevent the spread of diseases. The neutralization data generated in our laboratory have been included in the decision-making process of the National Advisory Committee on Immunization (NACI) in Canada. During the coronavirus 2019 (COVID-19) pandemic, the plaque reduction neutralization test (PRNT) has been the gold standard for determining neutralization of SARS-CoV-2. We validated a SARS-CoV-2 lentivirus surrogate neutralization assay (SCLSNA) as an alternative method to help support the PRNT. The advantages of using the SCLSNA is that it can process more samples, is less tedious to perform, and can be used in laboratories with a lower biosafety level. The use of the SCLSNA can further expand our capabilities to help fulfill the requirements for NACI and other important collaborations.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/diagnóstico , Pruebas de Neutralización/métodos , Anticuerpos Antivirales , Lentivirus/genética , Anticuerpos Neutralizantes
3.
Z Gerontol Geriatr ; 55(4): 287-291, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35391538

RESUMEN

BACKGROUND: Despite the care and support needs of migrants affected by dementia differing from the population of the country where they live now, most European countries do not provide specific strategies to address migration in their national dementia plans. The concept of intersectionality provides an innovative approach to dementia care perspectives and methodologies. OBJECTIVE: The aim is to define intersectionality and to provide examples of applying the concept to dementia care research, focusing on people with a migration background. METHODS: This article was conceptualized and discussed during virtual INTERDEM taskforce meetings in 2020/2021, while discussing identified literature on intersectionality, migration, and dementia care research. RESULTS: Using an intersectionality framework allows understanding of a person's lived experience by considering the dimensionality, co-occurrence and interlocking of factors (e.g., sex/gender, socioeconomic status, ethnicity, migration status, geographic location/place). CONCLUSION: Intersectionality can be applied as a conceptual and methodological approach to identify and address gaps in perspectives and in (dementia care) research to overcome the threat of ignorance, exclusion and discrimination.


Asunto(s)
Demencia , Migrantes , Demencia/diagnóstico , Demencia/terapia , Etnicidad , Humanos , Marco Interseccional , Clase Social
4.
Methods Mol Biol ; 2142: 59-71, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32367358

RESUMEN

Neutralizing antibodies against Zika virus (ZIKV) are a robust indicator of exposure to ZIKV. Here we describe the plaque reduction neutralization test (PRNT), which quantifies ZIKV-neutralizing antibodies (nAbs) by incubating infectious ZIKV with different dilutions of sera and applying the mixture to a susceptible Vero cell monolayer. After 4 days of incubation, neutral red dye is added to optimize the visualization of plaques caused by ZIKV cytopathic effect. Compared with controls, sera containing nAbs against ZIKV will demonstrate ≥90% reduction in the number of plaques observed. This protocol can be utilized for research applications and serological diagnostic testing with the use of additional controls.


Asunto(s)
Anticuerpos Antivirales/aislamiento & purificación , Pruebas de Neutralización/métodos , Ensayo de Placa Viral/métodos , Infección por el Virus Zika/diagnóstico , Virus Zika/inmunología , Animales , Anticuerpos Neutralizantes/metabolismo , Anticuerpos Antivirales/sangre , Especificidad de Anticuerpos , Chlorocebus aethiops , Grupos Control , Reacciones Cruzadas , Ensayo de Inmunoadsorción Enzimática/métodos , Humanos , Pruebas Serológicas/métodos , Células Vero , Infección por el Virus Zika/sangre , Infección por el Virus Zika/inmunología , Infección por el Virus Zika/virología
5.
Zoonoses Public Health ; 66(8): 909-917, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31449360

RESUMEN

Chikungunya virus (CHIKV) is a mosquito-borne pathogen that causes CHIKV fever. Definitive diagnosis is crucial for patients experiencing symptoms similar to other arboviral diseases because they can vary in clinical consequences. An increasing number of patients experience long-term rheumatic effects of CHIKV infection, but these cases may not be optimally detected by molecular assays and anti-CHIKV IgM ELISAs (M-ELISAs) used for confirmation and screening, respectively. The subsequent confirmatory serological test, the plaque reduction neutralization test (PRNT), is laborious and time-consuming. In this study, we evaluated a new diagnostic algorithm in which the M-ELISA is conducted in parallel with an anti-CHIKV IgG ELISA (G-ELISA) and observed that the Euroimmun M-ELISA combined with the Euroimmun G-ELISA or the Abcam G-ELISA exhibited excellent sensitivity and specificity for CHIKV. The combinations demonstrated perfect and near perfect inter-rater agreement with the PRNT, respectively, suggesting their potential to be used as alternatives to the confirmatory serological PRNT assay for CHIKV.


Asunto(s)
Anticuerpos Antiidiotipos/sangre , Anticuerpos Antivirales/sangre , Fiebre Chikungunya/diagnóstico , Ensayo de Inmunoadsorción Enzimática , Algoritmos , Fiebre Chikungunya/sangre , Fiebre Chikungunya/inmunología , Virus Chikungunya , Humanos , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , Juego de Reactivos para Diagnóstico/normas , Sensibilidad y Especificidad , Pruebas Serológicas
6.
Sci Rep ; 8(1): 15446, 2018 10 18.
Artículo en Inglés | MEDLINE | ID: mdl-30337601

RESUMEN

Missense mutations in glucocerebrosidase (GBA1) that impair the activity of the encoded lysosomal lipid metabolism enzyme (GCase) are linked to an increased risk of Parkinson's disease. However, reduced GCase activity is also found in brain tissue from Parkinson's disease patients without GBA1 mutations, implicating GCase dysfunction in the more common idiopathic form of Parkinson's disease. GCase is very highly expressed in monocytes, and thus we measured GCase activity in blood samples from recently diagnosed Parkinson's disease patients. Flow cytometry and immunoblotting assays were used to measure levels of GCase activity and protein in monocytes and lymphocytes from patients with Parkinson's disease (n = 48) and matched controls (n = 44). Gene sequencing was performed to screen participants for GBA1 missense mutations. In the Parkinson's disease patients, GCase activity was significantly reduced in monocytes, but not lymphocytes, compared to controls, even when GBA1 mutation carriers were excluded. Monocyte GCase activity correlated with plasma ceramide levels in the Parkinson's disease patients. Our results add to evidence for GCase dysfunction in idiopathic Parkinson's disease and warrant further work to determine if monocyte GCase activity associates with Parkinson's disease progression.


Asunto(s)
Ceramidas/sangre , Glucosilceramidasa/deficiencia , Monocitos/enzimología , Enfermedad de Parkinson/enzimología , Anciano , Progresión de la Enfermedad , Femenino , Citometría de Flujo , Genotipo , Glucosilceramidasa/análisis , Glucosilceramidasa/genética , Humanos , Linfocitos/enzimología , Masculino , Persona de Mediana Edad , Mutación Missense , Enfermedad de Parkinson/sangre , Interferencia de ARN , ARN Interferente Pequeño/genética
8.
BMC Nephrol ; 16: 181, 2015 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-26520140

RESUMEN

BACKGROUND: This study will assess measures of vascular health and inflammation in Aboriginal Australian adults with chronic kidney disease (CKD), and determine if intensive periodontal intervention improves cardiovascular health, progression of renal disease and periodontal health over a 24-month follow-up. METHODS: The study will be a randomised controlled trial. All participants will receive the periodontal intervention benefits, with the delayed intervention group receiving periodontal treatment 24 months following baseline. Inclusion criteria include being an Aboriginal Australian, having CKD (a. on dialysis; b. eGFR levels of < 60 mls/min/1.73 m(2) (CKD Stages 3 to 5); c. ACR ≥ 30 mg/mmol irrespective of eGFR (CKD Stages 1 and 2); d. diabetes plus albuminuria (ACR ≥ 3 mg/mmol) irrespective of eGFR), having moderate or severe periodontal disease, having at least 12 teeth, and living in Central Australia for the 2-year study duration. The intervention involves intensive removal of dental plaque biofilms by scaling, root-planing and removal of teeth that cannot be saved. The intervention will occur in three visits; baseline, 3-month and 6-month follow-up. The primary outcome will be changes in carotid intima-media thickness (cIMT). Secondary outcomes will include progression of CKD or death as a consequence of CKD/cardiovascular disease. Progression of CKD will be defined by time to the development of the first of: (1) new development of macroalbuminuria; (2) 30 % loss of baseline eGFR; (3) progression to end stage kidney disease defined by eGFR < 15 mLs/min/1.73 m(2); (4) progression to end stage kidney disease defined by commencement of renal replacement therapy. A sample size of 472 is necessary to detect a difference in cIMT of 0.026 mm (SD 0.09) at the significance criterion of 0.05 and a power of 0.80. Allowing for 20 % attrition, 592 participants are necessary at baseline, rounded to 600 for convenience. DISCUSSION: This will be the first RCT evaluating the effect of periodontal therapy on progression of CKD and cardiovascular disease among Aboriginal patients with CKD. Demonstration of a significant attenuation of CKD progression and cardiovascular disease has the potential to inform clinicians of an important, new and widely available strategy for reducing CKD progression and cardiovascular disease for Australia's most disadvantaged population. TRIAL REGISTRATION: This trial is registered with the Australian New Zealand Clinical Trial Registry ANZCTR12614001183673.


Asunto(s)
Enfermedades Cardiovasculares/mortalidad , Nativos de Hawái y Otras Islas del Pacífico/etnología , Nativos de Hawái y Otras Islas del Pacífico/estadística & datos numéricos , Enfermedades Periodontales/mortalidad , Enfermedades Periodontales/terapia , Insuficiencia Renal Crónica/mortalidad , Adulto , Anciano , Anciano de 80 o más Años , Australia/epidemiología , Enfermedades Cardiovasculares/prevención & control , Causalidad , Comorbilidad , Femenino , Humanos , Incidencia , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Pronóstico , Insuficiencia Renal Crónica/prevención & control , Factores de Riesgo , Tasa de Supervivencia , Resultado del Tratamiento , Adulto Joven
9.
Environ Sci Technol ; 48(9): 4765-73, 2014 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-24720846

RESUMEN

Waste incineration had been identified as an important source of ultrafine air pollutants resulting in elaborated treatment systems for exhaust air. Nowadays, these systems are able to remove almost all ultrafine particles. However, the fate of ultrafine particles caught in the filters has received little attention so far. Based on the use of engineered nano-objects (ENO) and their transfer into the waste stream, it can be expected that not only combustion generated nanoparticles are found in fly ashes but that many ENO finally end up in this matrix. A more detailed characterization of the nanoparticulate fraction of fly ashes is therefore needed. Physical and chemical characterizations were performed for fly ashes from five selected waste incineration plants (WIPs) with different input materials such as municipal waste, wood and sewage sludge. The intrinsic densities of the fly ashes were in the range of 2.7-3.2 g/cm(3). When the fly ash particle became airborne, the effective density depended on the particle size, increasing from 0.7-0.8 g/cm(3) for 100-150 nm to 2 g/cm(3) for 350-500 nm. The fly ash samples were fractionated at 2 µm, yielding fine fractions (<2 µm) and coarse fractions (>2 µm). The size distributions of the fine fractions in the airborne form were further characterized, which allowed calculation of the percentage of the fly ash particles below 100 nm. We found the highest mass-based percentage was about 0.07%; the number percentage in the fine fraction was in the range of 4.8% to 22%. Comparison with modeling results showed that ENO may constitute a considerable part of the fly ash particles below 100 nm. Chemical analyses showed that for the municipal waste samples Ca and Al were present in higher concentrations in the coarse fraction; for the mixed wood and sludge sample the P concentration was higher in the coarse fraction; for most other samples and elements they were enriched in the fine fraction. Electron microscopic images of fly ashes showed a wide range of particle sizes, from nanometer range to micrometer range. Many aggregated particles were observed, demonstrating that ENO, bulk-derived nano-objects and combustion-generated nano-objects can form aggregates in the incineration process.


Asunto(s)
Ceniza del Carbón/química , Incineración , Material Particulado/análisis , Administración de Residuos/métodos , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Tamaño de la Partícula , Aguas del Alcantarillado , Residuos Sólidos , Espectrometría por Rayos X , Suiza , Madera
10.
Environ Sci Process Impacts ; 15(1): 251-9, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24592442

RESUMEN

Little is known about the behavior of engineered nanomaterials (ENM) at the interface from the technosphere to the ecosphere. Previous modeling of ENM flows to the environment revealed that significant amounts of ENM enter the waste stream and therefore waste incineration plants and landfills. It is the aim of this study to model the flows of ENM during waste incineration and landfilling in greater depth by including a more detailed description of the different processes and considering ENM-specific transformation reactions. Four substances were modeled: nano-TiO2, nano-ZnO, nano-Ag and carbon nanotube (CNT). These ENM are representative for commonly used materials and products, illustrating a variety of ENM with different behavior. The modeling was performed for Switzerland where almost 100% of the municipal waste and sewage sludge are burned. The mass-based modeling showed that ­ despite several differences among the models for nano-TiO2, nano-ZnO and nano-Ag (e.g. partial dissolution of nano-ZnO in acid washing of exhaust air or fly ash) ­ the major ENM flows go from the waste incineration plant to the landfill as bottom ash. All other flows within the system boundary (e.g. with the fly ash) were predicted to be about one magnitude smaller than the bottom ash flow. A different ENM distribution was found for CNTs that are expected to burn to a large extent (94%) so that only insignificant amounts remain in the system. The results of the modeling show that waste incineration can have a strong influence on some ENM but that still the majority of the ENM-mass is expected to end up in landfills.


Asunto(s)
Monitoreo del Ambiente , Contaminantes Ambientales/análisis , Modelos Químicos , Nanoestructuras/análisis , Eliminación de Residuos
11.
Environ Sci Pollut Res Int ; 19(2): 550-8, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21850484

RESUMEN

PURPOSE: Nanoscale zero valent iron (NZVI) is emerging as a new option for the treatment of contaminated soil and groundwater targeting mainly chlorinated organic contaminants (e.g., solvents, pesticides) and inorganic anions or metals. The purpose of this article is to give a short overview of the practical experience with NZVI applications in Europe and to present a comparison to the situation in the USA. Furthermore, the reasons for the difference in technology use are discussed. METHOD: The results in this article are based on an extensive literature review and structured discussions in an expert workshop with experts from Europe and the USA. The evaluation of the experiences was based on a SWOT (strength, weakness, opportunity, threat) analysis. RESULT: There are significant differences in the extent and type of technology used between NZVI applications in Europe and the USA. In Europe, only three full-scale remediations with NZVI have been carried out so far, while NZVI is an established treatment method in the USA. Bimetallic particles and emulsified NZVI, which are extensively used in the USA, have not yet been applied in Europe. Economic constraints and the precautionary attitude in Europe raise questions regarding whether NZVI is a cost-effective method for aquifer remediation. Challenges to the commercialization of NZVI include mainly non-technical aspects such as the possibility of a public backlash, the fact that the technology is largely unknown to consultants, governments and site owners as well as the lack of long-term experiences. CONCLUSION: Despite these concerns, the results of the current field applications with respect to contaminant reduction are promising, and no major adverse impacts on the environment have been reported so far. It is thus expected that these trials will contribute to promoting the technology in Europe.


Asunto(s)
Biodegradación Ambiental , Monitoreo del Ambiente/métodos , Agua Subterránea/química , Hierro/química , Nanopartículas del Metal/química , Contaminantes Químicos del Agua/análisis , Contaminación Ambiental/análisis , Europa (Continente) , Proyectos Piloto , Contaminantes del Suelo/análisis , Estados Unidos
12.
J Hazard Mater ; 211-212: 275-80, 2012 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-22154870

RESUMEN

Nanofiltration is frequently associated with nanotechnology - obviously because of its name. However, the term "nano" in nanofiltration refers - according to the definition of the International Union of Pure and Applied Chemistry (IUPAC) - to the size of the particles rejected and not to a nanostructure as defined by the International Organisation of Standardisation (ISO) in the membrane. Evidently, the approach to standardisation of materials differs significantly between membrane technology and nanotechnology which leads to considerable confusion and inconsistent use of the terminology. There are membranes that can be unambiguously attributed to both membrane technology and nanotechnology such as those that are functionalized with nanoparticles, while the classification of hitherto considered to be conventional membranes as nanostructured material is questionable. A driving force behind the efforts to define nanomaterials is not least the urgent need for the regulation of the use of nanomaterials. Since risk estimation is the basis for nanotechnology legislation, the risk associated with nanomaterials should also be reflected in the underlying standards and definitions. This paper discusses the impacts of the recent attempts to define nanomaterials on membrane terminology in the light of risk estimations and the need for regulation.


Asunto(s)
Filtración/instrumentación , Membranas Artificiales , Nanotecnología , Filtración/métodos , Nanoestructuras , Medición de Riesgo
13.
Dalton Trans ; 39(36): 8472-6, 2010 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-20461254

RESUMEN

Nonracemic aryl-substituted alpha-methyldihydrocinnamaldehyde derivatives employed as olfactory principles in perfumes (Lilial, Helional) were obtained via enzymatic reduction of the corresponding cinnamaldehyde precursors using cloned and overexpressed ene-reductases. (R)-Enantiomers were obtained using the old-yellow-enzyme (OYE) homolog YqjM from Bacillus subtilis and 12-oxophytodienoic acid reductase isoenzyme OPR1 from tomato (e.e.(max) 53%), and (S)-aldehydes were furnished in up to 97% e.e. using isoenzyme OPR3, nicotinamide 2-cyclohexene-1-one reductase NCR from Zymomonas mobilis and yeast OYE isoenzymes 1-3 under optimised reaction conditions in the presence of t-butyl methyl ether as the co-solvent. The stereochemical outcome of the reduction of alpha-methylcinnamaldehyde using NCR and OYEs 1-3 [previously reported to be (R)] was unambiguously corrected to be (S).


Asunto(s)
Acroleína/análogos & derivados , Aldehídos/metabolismo , Enzimas/metabolismo , Perfumes/metabolismo , Acroleína/química , Aldehídos/química , Bacillus subtilis/enzimología , Proteínas Bacterianas/metabolismo , Sitios de Unión , Biocatálisis , Proteínas Fúngicas/metabolismo , Solanum lycopersicum/enzimología , Modelos Moleculares , NADPH Deshidrogenasa/metabolismo , Oxidación-Reducción , Oxidorreductasas/metabolismo , Oxidorreductasas actuantes sobre Donantes de Grupo CH-CH/metabolismo , Perfumes/química , Proteínas de Plantas/metabolismo , Estereoisomerismo , Zymomonas/enzimología
14.
Org Biomol Chem ; 7(6): 1115-9, 2009 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-19262930

RESUMEN

Three FMN-dependent oxidoreductases, YcnD and YhdA from Bacillus subtilis and Lot6p from Saccharomyces cerevisiae, oxidised alpha,beta-unsaturated carbonyl compounds and a thioether, respectively, to furnish the corresponding racemic epoxides or sulfoxide, respectively. The mechanism of this enzyme-mediated (rather than enzyme-catalysed) oxidation was shown to proceed via the NADH-dependent reduction of O(2), forming H(2)O(2), which acted as oxidant in a spontaneous (non-enzymatic) fashion.


Asunto(s)
Compuestos Epoxi/metabolismo , FMN Reductasa/metabolismo , Compuestos de Sulfhidrilo/metabolismo , Sulfuros/metabolismo , Bacillus subtilis/enzimología , Compuestos Epoxi/química , Estructura Molecular , Oxidación-Reducción , Saccharomyces cerevisiae/enzimología , Estereoisomerismo , Compuestos de Sulfhidrilo/química , Sulfuros/química
15.
Neurourol Urodyn ; 28(4): 313-9, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19058189

RESUMEN

AIMS: There are still controversies regarding the reproducibility of cystometric data and no objective measurement of bladder sensations is currently available. Additionally, very little information exists about autonomic activity during standard filling cystometry (FC). The aim of this study was to evaluate the use of heart rate variability (HRV) analysis as a reliable monitor of the autonomic nervous system and objective measure for bladder sensations during FC. METHODS: In a volunteer sample of healthy female subjects a standard FC at 25 ml/min was performed, using an 8 Fr microtip catheter with integrated pressure transducers. During FC, subjects had to indicate first sensation of filling (FSF), first desire to void (FDV) and strong desire to void (SDV). A 3-lead electrocardiogram was continuously recorded. After 5 h all measurements were repeated. Power spectrum analysis was used to analyse HRV, to obtain low frequency (LF) and high frequency (HF) parameters, from which the LF/HF ratio was derived. RESULTS: 12 subjects with a mean age of 23.3 +/- 2.3 years could be included. 11 of 12 subjects completed both measurement sessions. One subjects had to be excluded, due to irritating urethral discomfort following catheterisation. The LF/HF ratio showed a reproducible activation pattern in the healthy subjects with a stable sympathovagal balance until FDV. Before SDV was indicated, the sympathovagal balance started to shift towards sympathetic activation and caused a significant increase in LF/HF. CONCLUSION: HRV analysis seems to be a useful indicator for the general activation pattern of the sympathovagal balance during FC, correlating the intensity of the bladder filling sensation to stress and sympathetic activation.


Asunto(s)
Sistema Nervioso Autónomo/fisiología , Frecuencia Cardíaca/fisiología , Vejiga Urinaria/fisiología , Urodinámica/fisiología , Adolescente , Adulto , Artefactos , Electrocardiografía , Femenino , Humanos , Presión , Sensación , Uretra/fisiología , Vejiga Urinaria/inervación , Adulto Joven
16.
Environ Sci Technol ; 42(12): 4447-53, 2008 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-18605569

RESUMEN

The aim of this study was to use a life-cycle perspective to model the quantities of engineered nanoparticles released into the environment. Three types of nanoparticles were studied: nano silver (nano-Ag), nano TiO2 (nano-TiO2), and carbon nanotubes (CNT). The quantification was based on a substance flow analysis from products to air, soil, and water in Switzerland. The following parameters were used as model inputs: estimated worldwide production volume, allocation of the production volume to product categories, particle release from products, and flow coefficients within the environmental compartments. The predicted environmental concentrations (PEC) were then compared to the predicted no effect concentrations (PNEC) derived from the literature to estimate a possible risk. The expected concentrations of the three nanoparticles in the different environmental compartments vary widely, caused by the different life cycles of the nanoparticle-containing products. The PEC values for nano-TiO2 in water are 0.7--16 microg/L and close to or higher than the PNEC value for nano-TiO2 (< 1 microg/L). The risk quotients (PEC/PNEC) for CNT and nano-Ag were much smaller than one, therefore comprising no reason to expect adverse effects from those particles. The results of this study make it possible for the first time to carry out a quantitative risk assessment of nanoparticles in the environment and suggest further detailed studies of nano-TiO2.


Asunto(s)
Exposición a Riesgos Ambientales , Nanopartículas
17.
Cancer Res ; 68(2): 597-604, 2008 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-18199557

RESUMEN

The clinical efficacy of the CD20-specific chimeric monoclonal antibody rituximab is significantly hampered by intrinsic or acquired resistance to therapy. Rituximab activates antibody-dependent cellular cytotoxicity/complement-dependent cytotoxicity-dependent lysis but also induces apoptosis by cross-linking of its target antigen CD20. Recent reports indicate that this apoptotic activity of rituximab can be synergized by cotreatment with Fas agonists. Here, we report on a strategy designed to exploit and optimize the synergy between rituximab and Fas signaling by genetically fusing a rituximab-derived antibody fragment to soluble Fas ligand (sFasL). The resultant fusion protein, designated scFvRit:sFasL, potently induced CD20-restricted apoptosis in a panel of malignant B-cell lines (10 of 11) and primary patient-derived malignant B cells (two of two non-Hodgkin lymphoma and five of six B cell chronic lymphocytic leukemia). ScFvRit:sFasL efficiently activated CD20 and Fas apoptotic signaling, resulting in a far superior proapoptotic activity compared with cotreatment with rituximab and Fas agonists. ScFvRit:sFasL lacked activity toward normal human B cells and also lacked systemic toxicity in nude mice with no elevation of aspartate aminotransferase and alanine aminotransferase levels or liver caspase-3 activity. In conclusion, scFvRit:sFasL efficiently activates CD20 and Fas-apoptotic signaling and may be useful for the elimination of malignant B cells.


Asunto(s)
Anticuerpos Monoclonales/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Proteína Ligando Fas/agonistas , Terapia Genética , Leucemia Linfocítica Crónica de Células B/terapia , Linfoma no Hodgkin/terapia , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/uso terapéutico , Animales , Anticuerpos Monoclonales de Origen Murino , Apoptosis/efectos de los fármacos , Apoptosis/genética , Linfocitos B/efectos de los fármacos , Células CHO , Cricetinae , Cricetulus , Femenino , Terapia Genética/efectos adversos , Terapia Genética/métodos , Humanos , Leucemia Linfocítica Crónica de Células B/genética , Linfoma no Hodgkin/genética , Masculino , Proteínas Recombinantes de Fusión/efectos adversos , Rituximab , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética , Anticuerpos de Cadena Única , Células Tumorales Cultivadas
18.
Clin Neurol Neurosurg ; 106(4): 275-9, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15296999

RESUMEN

Daytime sleepiness and cataplexy can increase automobile accident rates in narcolepsy. Several countries have produced guidelines for issuing a driving license. The aim of the study was to compare driving simulator performance and neuropsychological test results in narcolepsy in order to evaluate their predictive value regarding driving ability. Thirteen patients with narcolepsy (age: 41.5+/-12.9 years) and 10 healthy control patients (age: 55.1+/-7.8 years) were investigated. By computer-assisted neuropsychological testing, vigilance, alertness and divided attention were assessed. In a driving simulator patients and controls had to drive on a highway for 60 min (mean speed of 100 km/h). Different weather and daytime conditions and obstacles were presented. Epworth Sleepiness Scale-Scores were significantly raised (narcolepsy patients: 16.7+/-5.1, controls: 6.6+/-3.6, P < or = 0.001). The accident rate of the control patients increased (3.2+/-1.8 versus 1.3+/-1.5, P < or = 0.01). Significant differences in concentration lapses (e.g. tracking errors and deviation from speed limit) could not be revealed (9.8+/-3.5 versus 7.1+/-3.2, pns). Follow-up investigation in five patients after an optimising therapy could demonstrate the decrease in accidents due to concentration lapses (P < or = 0.05). Neuropsychological testing (expressed as percentage compared to a standardised control population) revealed deficits in alertness (32.3+/-28.6). Mean percentage scores of divided attention (56.9+/-25.4) and vigilance (58.7+/-26.8) were in a normal range. There was, however, a high inter-individual difference. There was no correlation between driving performance and neuropsychological test results or ESS Score. Neuropsychological test results did not significantly change in the follow-up. The difficulties encountered by the narcolepsy patient in remaining alert may account for sleep-related motor vehicle accidents. Driving simulator investigations are closely related to real traffic situations than isolated neuropsychological tests. At the present time the driving simulator seems to be a useful instrument judging driving ability especially in cases with ambiguous neuropsychological results.


Asunto(s)
Conducción de Automóvil , Simulación por Computador , Narcolepsia/psicología , Pruebas Neuropsicológicas , Adulto , Atención , Femenino , Humanos , Masculino , Persona de Mediana Edad , Narcolepsia/fisiopatología , Valor Predictivo de las Pruebas , Tiempo de Reacción , Vigilia
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