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1.
Environ Sci Technol ; 57(43): 16541-16551, 2023 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-37853526

RESUMO

Microplastics (MP) including tire wear particles (TWP) are ubiquitous. However, their mass loads, transport, and vertical behavior in water bodies and overlying air are never studied simultaneously before. Particularly, the sea surface microlayer (SML), a ubiquitous, predominantly organic, and gelatinous film (<1 mm), is interesting since it may favor MP enrichment. In this study, a remote-controlled research catamaran simultaneously sampled air, SML, and underlying water (ULW) in Swedish fjords of variable anthropogenic impacts (urban, industrial, and rural) to fill these knowledge gaps in the marine-atmospheric MP cycle. Polymer clusters and TWP were identified and quantified with pyrolysis-gas chromatography-mass spectrometry. Air samples contained clusters of polyethylene terephthalate, polycarbonate, and polystyrene (max 50 ng MP m-3). In water samples (max. 10.8 µg MP L-1), mainly TWP and clusters of poly(methyl methacrylate) and polyethylene terephthalate occurred. Here, TWP prevailed in the SML, while the poly(methyl methacrylate) cluster dominated the ULW. However, no general MP enrichment was observed in the SML. Elevated anthropogenic influences in urban and industrial compared to the rural fjord areas were reflected by enhanced MP levels in these areas. Vertical MP movement behavior and distribution were not only linked to polymer characteristics but also to polymer sources and environmental conditions.


Assuntos
Microplásticos , Poluentes Químicos da Água , Água , Plásticos/análise , Água do Mar/análise , Água do Mar/química , Polietilenotereftalatos , Polimetil Metacrilato , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodos
2.
Anal Chem ; 93(49): 16360-16368, 2021 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-34807556

RESUMO

Herein we report on a deep-learning method for the removal of instrumental noise and unwanted spectral artifacts in Fourier transform infrared (FTIR) or Raman spectra, especially in automated applications in which a large number of spectra have to be acquired within limited time. Automated batch workflows allowing only a few seconds per measurement, without the possibility of manually optimizing measurement parameters, often result in challenging and heterogeneous datasets. A prominent example of this problem is the automated spectroscopic measurement of particles in environmental samples regarding their content of microplastic (MP) particles. Effective spectral identification is hampered by low signal-to-noise ratios and baseline artifacts as, again, spectral post-processing and analysis must be performed in automated measurements, without adjusting specific parameters for each spectrum. We demonstrate the application of a simple autoencoding neural net for reconstruction of complex spectral distortions, such as high levels of noise, baseline bending, interferences, or distorted bands. Once trained on appropriate data, the network is able to remove all unwanted artifacts in a single pass without the need for tuning spectra-specific parameters and with high computational efficiency. Thus, it offers great potential for monitoring applications with a large number of spectra and limited analysis time with availability of representative data from already completed experiments.


Assuntos
Aprendizado Profundo , Microplásticos , Análise de Fourier , Plásticos , Espectroscopia de Infravermelho com Transformada de Fourier
3.
Gerontol Geriatr Educ ; 41(1): 109-120, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31319778

RESUMO

This study focuses on nurse educators' perspectives on teaching gerontology within nursing curricula in two cultures. An increasing aging multi-cultural population with large caring needs requires not only informal elder care provided by family members, but also professional nursing staff trained in gerontology. The aim of this study was to explore how Swedish and Thai nurse educators describe the role of teaching gerontology within nursing educations in Sweden and Thailand. Method: Qualitative open-ended interviews with 13 Swedish and Thai nurse educators were conducted and analyzed with qualitative content analysis. Findings: There is a lack of gerontological nursing competence in faculty, as well as bureaucracy impeding necessary changes of curricula, together with difficulties in highlighting positive and cultural aspects of aging. Conclusions: Pedagogical strategies need to be developed by nurse educators specialized in cross-cultural gerontology to improve current and future nursing educations in both countries.


Assuntos
Comparação Transcultural , Docentes de Enfermagem/psicologia , Enfermagem Geriátrica/educação , Adulto , Currículo , Educação em Enfermagem/normas , Feminino , Geriatria/educação , Humanos , Masculino , Pessoa de Meia-Idade , Pesquisa Qualitativa , Suécia , Tailândia
4.
Environ Sci Technol ; 49(1): 553-61, 2015 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-25380515

RESUMO

The use of nanoparticles in consumer products, for example, cosmetics, sunscreens, and electrical devices, has increased tremendously over the past decade despite insufficient knowledge about their effects on human health and ecosystem function. Moreover, the amount of plastic waste products that enter natural ecosystems, such as oceans and lakes, is increasing, and degradation of the disposed plastics produces smaller particles toward the nano scale. Therefore, it is of utmost importance to gain knowledge about how plastic nanoparticles enter and affect living organisms. Here we have administered 24 and 27 nm polystyrene nanoparticles to fish through an aquatic food chain, from algae through Daphnia, and studied the effects on behavior and metabolism. We found severe effects on feeding and shoaling behavior as well as metabolism of the fish; hence, we conclude that polystyrene nanoparticles have severe effects on both behavior and metabolism in fish and that commonly used nanosized particles may have considerable effects on natural systems and ecosystem services derived from them.


Assuntos
Comportamento Animal/efeitos dos fármacos , Exposição Ambiental , Peixes/metabolismo , Peixes/fisiologia , Nanopartículas/toxicidade , Poliestirenos/toxicidade , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Daphnia/fisiologia , Comportamento Alimentar/efeitos dos fármacos , Humanos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Espectroscopia de Ressonância Magnética , Metabolômica
5.
Scand J Caring Sci ; 28(4): 793-801, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24433250

RESUMO

INTRODUCTION: In earlier research as well as in political discussion and documents, the topic of evidence has been highlighted as one of the most important concerns in nursing care. This study focuses on understanding what lies behind nurses' ways of acting regarding evidence-based nursing through an illumination of the way they perceive the phenomena. AIM: The aim was to identify and describe the different ways municipal care nurses perceive aspects of working with evidence when nursing frail older adults. METHODS: An explorative design with a phenomenographic approach based on interviews with nurses working with home-based care within the municipality was used in order to gain understanding of nurse's perceptions of the phenomena. RESULTS: Findings revealed that the nurses perceived a variety of aspects when working with evidence when nursing frail older people. Aspects with a spectra of different perceptions shown in the analysis were as follows: Evidence-based nursing as a desired intention/mission, lack of practical supporting structures to apply evidence, lack of confidence in own capacity to apply evidence and a belief that it will work anyway. CONCLUSIONS: Findings reveal that it is a challenge to implement research both on an individual as well as on an organisational level. Understanding the contextual perceptions of evidence by nurses can cast light on the barriers as well as the prerequisites of working with evidence while caring for frail older adults in municipal care.


Assuntos
Enfermagem Baseada em Evidências , Idoso Fragilizado , Recursos Humanos de Enfermagem , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Entrevistas como Assunto , Masculino , Relações Enfermeiro-Paciente
6.
Talanta ; 269: 125435, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38070287

RESUMO

Anthropogenic particles, including microplastics, are receiving ever-increasing concern due to their potential environmental impact. Surveys and monitoring require sampling from many environmental and biological matrices, including natural water, drinking water, sediment, and air. However, there are no standard methods for sampling particles in the environment; thereby, many different approaches are used for both single particle and ensemble distribution or bulk chemical analyses. In the microplastics field, particles are often analyzed on membranes using automated analysis with spectroscopic techniques such as Fourier-transform infrared spectroscopy (FTIR) and Raman spectroscopy. For automated analysis, the filters' properties are crucial. We coated polycarbonate (PC) membranes with 100 nm platinum (Pt) on both side using a e-beam evaporator and evaluated their suitability for filtrating and analysis of environmental samples. The PC membranes have a defined and practical pore size, available in many pore sizes and with circular diameter of 47 mm and 25 mm. Our Pt coated membranes can handle large volumes of fresh and marine waters, high pressure, and various treatment solutions. Moreover, they have good optical properties for imaging with light microscopy (LM) and Scanning Electron Microscopy (SEM), and no disturbing background signal for Raman or FTIR spectroscopy analysis.

7.
Microplast nanoplast ; 3(1): 24, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37920865

RESUMO

Plastics pollution research attracts scientists from diverse disciplines. Many Early Career Researchers (ECRs) are drawn to this field to investigate and subsequently mitigate the negative impacts of plastics. Solving the multi-faceted plastic problem will always require breakthroughs across all levels of science disciplinarity, which supports interdisciplinary discoveries and underpins transdisciplinary solutions. In this context, ECRs have the opportunity to work across scientific discipline boundaries and connect with different stakeholders, including industry, policymakers and the public. To fully realize their potential, ECRs need to develop strong communication and project management skills to be able to effectively interface with academic peers and non-academic stakeholders. At the end of their formal education, many ECRs will choose to leave academia and pursue a career in private industry, government, research institutes or non-governmental organizations (NGOs). Here we give perspectives on how ECRs can develop the skills to tackle the challenges and opportunities of this transdisciplinary research field and how these skills can be transferred to different working sectors. We also explore how advisors can support an ECRs' growth through inclusive leadership and coaching. We further consider the roles each party may play in developing ECRs into mature scientists by helping them build a strong foundation, while also critically assessing problems in an interdisciplinary and transdisciplinary context. We hope these concepts can be useful in fostering the development of the next generation of plastics pollution researchers so they can address this global challenge more effectively.

8.
J Transcult Nurs ; 33(3): 446-455, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35000509

RESUMO

INTRODUCTION: There is an urgent need for registered nurses with gerontological competence within long-term care (LTC) of older adults. Despite increases of life expectancy, LTC for older adults is not emphasized in nursing curricula in neither Sweden nor Thailand. Thus, the aim was to explore conceptions on gerontological nursing (GN) among Swedish and Thai nurse educators. METHOD: A qualitative phenomenographic method, based on open-ended interviews with five Thai and nine Swedish nurse educators was conducted. RESULTS: The results indicate a paradox between the educators' knowledge about the implications of global aging, their hope of own aging, and LTC. The ethical responsibility of being credible and a source of inspiration in teaching about aging are focused, while GN seem to be less important. DISCUSSION: To increase students' interest in GN, measures need to be taken within the educational arenas, where the educators' own conceptions toward GN, cultural aspects of aging, and LTC are discussed.


Assuntos
Bacharelado em Enfermagem , Geriatria , Estudantes de Enfermagem , Idoso , Docentes de Enfermagem , Humanos , Suécia , Ensino , Tailândia
9.
Sci Rep ; 12(1): 15459, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36104387

RESUMO

The ubiquitous occurrence of anthropogenic particles, including microplastics in the marine environment, has, over the last years, gained worldwide attention. As a result, many methods have been developed to estimate the amount and type of microplastics in the marine environment. However, there are still no standardized protocols for how different marine matrices should be sampled or how to extract and identify these particles, making meaningful data comparison hard. Buoyant microplastics are influenced by winds and currents, and concentrations could hence be expected to be highly variable over time. However, since both high density and most of the initially buoyant microplastics are known to eventually sink and settle on the seafloor, marine sediments are proposed as a suitable matrix for microplastics monitoring. Several principles, apparatuses, and protocols for extracting microplastics from marine sediments have been presented, but extensive comparison of the different steps in the protocols using real environmental samples is lacking. Thus, in this study, different pre-treatment and subsequent density separation protocols for extraction of microplastics from replicate samples of marine sediment were compared. Two pre-treatment methods, one using inorganic chemicals (NaClO + KOH + Na4P2O7) and one using porcine pancreatic enzymes, as well as one with no pre-treatment of the sediment, were compared in combination with two commonly used high-density saline solutions used for density separation, sodium chloride (NaCl) and zinc chloride (ZnCl2). Both pre-treatment methods effectively removed organic matter, and both saline solutions extracted lighter plastic particles such as polyethylene (PE) and polypropylene (PP). The most efficient combination, chemical pre-treatment and density separation with ZnCl2, was found to extract > 15 times more particles (≥ 100 µm) from the sediment than other treatment combinations, which could largely be explained by the high presence and efficient extraction of PVC particles.


Assuntos
Microplásticos , Poluentes Químicos da Água , Animais , Monitoramento Ambiental/métodos , Sedimentos Geológicos , Plásticos , Suínos , Poluentes Químicos da Água/análise
10.
Artigo em Inglês | MEDLINE | ID: mdl-34052753

RESUMO

Glycosaminoglycans (GAGs) are long linear sulfated polysaccharides implicated in processes linked to disease development such as mucopolysaccharidosis, respiratory failure, cancer, and viral infections, thereby serving as potential biomarkers. A successful clinical translation of GAGs as biomarkers depends on the availability of standardized GAG measurements. However, owing to the analytical complexity associated with the quantification of GAG concentration and structural composition, a standardized method to simultaneously measure multiple GAGs is missing. In this study, we sought to characterize the analytical performance of a ultra-high-performance liquid chromatography coupled with triple-quadrupole tandem mass spectrometry (UHPLC-MS/MS)-based kit for the quantification of 17 free GAG disaccharides. The kit showed acceptable linearity, selectivity and specificity, accuracy and precision, and analyte stability in the absolute quantification of 15 disaccharides. In native human samples, here using urine as a reference matrix, the analytical performance of the kit was acceptable for the quantification of CS disaccharides. Intra- and inter-laboratory tests performed in an external laboratory demonstrated robust reproducibility of GAG measurements showing that the kit was acceptably standardized. In conclusion, these results indicated that the UHPLC-MS/MS kit was standardized for the simultaneous measurement of free GAG disaccharides allowing for comparability of measurements and enabling translational research.


Assuntos
Glicosaminoglicanos/urina , Espectrometria de Massas em Tandem/métodos , Adulto , Cromatografia Líquida de Alta Pressão/métodos , Humanos , Modelos Lineares , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
11.
Eur J Cancer ; 114: 55-66, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31059974

RESUMO

BACKGROUND: Thymidine kinase 1 (TK1) plays a critical role in DNA synthesis and cell proliferation. Recent studies have shown potential for serum TK1 activity (sTKa) as a prognostic marker and indicator of early response to endocrine therapy in advanced breast cancer. The aim of this study is to assess the correlation between sTKa and patient outcome. PATIENTS AND METHODS: The Evaluation of Faslodex versus Exemestane Clinical Trial (EFECT) was a double-blind, double-dummy, randomised trial of fulvestrant versus exemestane after progression on non-steroidal aromatase inhibitor therapy, in postmenopausal women with advanced breast cancer. Retrospective analyses of serum archived from EFECT were conducted. sTKa was assessed using the DiviTum® assay on samples collected at baseline, after three and six months of endocrine therapy, and at disease progression. RESULTS: The median time to progression (mTTP) for patients with low baseline sTKa levels was 5.03 months (95% confidence interval [CI]: 3.91-5.89) versus 2.57 months (95% CI: 2.04-3.52) in patients with high sTKa baseline levels (P < 0.0001). On treatment, patients whose sTKa increased from baseline had a significantly shorter mTTP (3.39 months, 95% CI: 2.14-4.11) than those without an sTKa increase (5.39 months, 95% CI: 4.01-6.68) (P = 0.0045). Similar results were observed in the separate EFECT treatment arms. After adjusting for major prognostic factors, sTKa remained an independent marker. CONCLUSION: sTKa is a potential circulating prognostic marker in patients with advanced breast cancer treated with endocrine therapy. It may also represent a tool for upfront identification of endocrine therapy resistance and early positive response to therapy. Independent validation of these results is warranted.


Assuntos
Androstadienos/uso terapêutico , Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Fulvestranto/uso terapêutico , Timidina Quinase/uso terapêutico , Idoso , Androstadienos/farmacologia , Antineoplásicos/farmacologia , Neoplasias da Mama/complicações , Feminino , Fulvestranto/farmacologia , Humanos , Metástase Neoplásica , Prognóstico , Timidina Quinase/farmacologia
12.
Nanotoxicology ; 12(8): 885-900, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30053796

RESUMO

The use of manufactured nanomaterials is rapidly increasing, while our understanding of the consequences of releasing these materials into the environment is still limited and many questions remain, for example, how do nanoparticles affect living organisms in the wild? How do organisms adapt and protect themselves from exposure to foreign materials? How does the environment affect the performance of nanoparticles, including their surface properties? In an effort to address these crucial questions, our main aim has been to probe the effects of aquatic organisms on nanoparticle aggregation. We have, therefore, carried out a systematic study with the purpose to disentangle the effects of the freshwater zooplankter, Daphnia magna, on the surface properties, stability, and aggregation properties of gold (Au) nanoparticles under different aqueous conditions as well as identified the proteins bound to the nanoparticle surface. We show that Au nanoparticles aggregate in pure tap water, but to a lesser extent in water that either contains Daphnia or has been pre-conditioned with Daphnia. Moreover, we show that proteins generated by Daphnia bind to the Au nanoparticles and create a modified surface that renders them less prone to aggregation. We conclude that the surrounding milieu, as well as the surface properties of the original Au particles, are important factors in determining how the nanoparticles are affected by biological metabolism. In a broader context, our results show how nanoparticles released into a natural ecosystem become chemically and physically altered through the dynamic interactions between particles and organisms, either through biological metabolism or through the interactions with biomolecules excreted by organisms into the environment.


Assuntos
Daphnia/metabolismo , Ouro/metabolismo , Nanopartículas Metálicas/química , Animais , Água Doce , Regulação da Expressão Gênica/efeitos dos fármacos , Ouro/química , Água/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/metabolismo
13.
Mol Cancer ; 6: 28, 2007 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-17433107

RESUMO

The latency-associated nuclear antigen (LANA-1) of Human Herpes Virus 8 (HHV-8), alternatively called Kaposi Sarcoma Herpes Virus (KSHV) is constitutively expressed in all HHV-8 infected cells. LANA-1 accumulates in well-defined foci that co-localize with the viral episomes. We have previously shown that these foci are tightly associated with the borders of heterochromatin 1. We have also shown that exogenously expressed LANA-1 causes an extensive re-organization of Hoechst 33248 DNA staining patterns of the nuclei in non-HHV-8 infected cells 2. Here we show that this effect includes the release of the bulk of DNA from heterochromatic areas, in both human and mouse cells, without affecting the overall levels of heterochromatin associated histone H3 lysine 9 tri-methylation (3MK9H3). The release of DNA from the heterochromatic chromocenters in LANA-1 transfected mouse cells co-incides with the dispersion of the chromocenter associated methylcytosin binding protein 2 (MECP2). The localization of 3MK9H3 to the remnants of the chromocenters remains unaltered. Moreover, exogeneously expressed LANA-1 leads to the relocation of the chromocenters to the nuclear periphery, indicating extensive changes in the positioning of the chromosomal domains in the LANA-1 harboring interphase nucleus. Using a series of deletion mutants we have shown that the chromatin rearranging effects of LANA-1 require the presence of a short (57 amino acid) region that is located immediately upstream of the internal acidic repeats. This sequence lies within the previously mapped binding site to histone methyltransferase SUV39H1. We suggest that the highly concentrated LANA-1, anchored to the host genome in the nuclear foci of latently infected cells and replicated through each cell generation, may function as "epigenetic modifier". The induction of histone modification in adjacent host genes may lead to altered gene expression, thereby contributing to the viral oncogenesis.


Assuntos
Antígenos Virais/metabolismo , Herpesvirus Humano 8/fisiologia , Heterocromatina/metabolismo , Proteínas Nucleares/metabolismo , Animais , Linhagem Celular Tumoral , DNA de Neoplasias/metabolismo , Células HeLa , Herpesvirus Humano 8/química , Humanos , Proteína 2 de Ligação a Metil-CpG/metabolismo , Camundongos , Células NIH 3T3 , Deleção de Sequência
14.
Contemp Nurse ; 53(1): 36-47, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27821017

RESUMO

BACKGROUND: Negative views towards ageing and older adults may be a reason why nurses do not choose to work in gerontological nursing. Studying in another cultural context can challenge these views. The Objective was to explore nursing students' views on ageing and older adults before and after a gerontology course held abroad. DESIGN AND METHOD: A qualitative approach based on content analysis of responses to open-ended questions by 30 Thai nursing students studying a gerontology course in Sweden. RESULTS: Three main categories: positive imprints of ageing, ageing takes its toll, and knowledge leading to action, emerged through sub-categories carrying a view of older adults as not only in need of care, but also as resourceful and competent. Professional healthcare, besides family was seen as potential caregivers in old age. CONCLUSIONS: Studying gerontology abroad can widen views towards ageing and older adults, inspiring nurses to work in gerontological nursing.


Assuntos
Envelhecimento/psicologia , Currículo , Bacharelado em Enfermagem/organização & administração , Enfermagem Geriátrica/educação , Enfermeiros Internacionais/psicologia , Estudantes de Enfermagem/psicologia , Adulto , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Pesquisa Qualitativa , Suécia , Tailândia
15.
Sci Rep ; 7(1): 11452, 2017 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-28904346

RESUMO

The tremendous increases in production of plastic materials has led to an accumulation of plastic pollution worldwide. Many studies have addressed the physical effects of large-sized plastics on organisms, whereas few have focused on plastic nanoparticles, despite their distinct chemical, physical and mechanical properties. Hence our understanding of their effects on ecosystem function, behaviour and metabolism of organisms remains elusive. Here we demonstrate that plastic nanoparticles reduce survival of aquatic zooplankton and penetrate the blood-to-brain barrier in fish and cause behavioural disorders. Hence, for the first time, we uncover direct interactions between plastic nanoparticles and brain tissue, which is the likely mechanism behind the observed behavioural disorders in the top consumer. In a broader perspective, our findings demonstrate that plastic nanoparticles are transferred up through a food chain, enter the brain of the top consumer and affect its behaviour, thereby severely disrupting the function of natural ecosystems.


Assuntos
Lesões Encefálicas/veterinária , Doenças dos Peixes/etiologia , Cadeia Alimentar , Nanopartículas , Plásticos , Animais , Poluição Ambiental , Mortalidade , Poluentes Químicos da Água
16.
Nanotoxicology ; 10(8): 1160-7, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27181920

RESUMO

Nanowires (NWs) have unique electrical and optical properties of value for many applications including lighting, sensing, and energy harnessing. Consumer products containing NWs increase the risk of NWs being released in the environment, especially into aquatic ecosystems through sewage systems. Daphnia magna is a common, cosmopolitan freshwater organism sensitive to toxicity tests and represents a likely entry point for nanoparticles into food webs of aquatic ecosystems. Here we have evaluated the effect of NW diameter on the gut penetrance of NWs in Daphnia magna. The animals were exposed to NWs of two diameters (40 and 80 nm) and similar length (3.6 and 3.8 µm, respectively) suspended in water. In order to locate the NWs in Daphnia, the NWs were designed to comprise one inherently fluorescent segment of gallium indium phosphide (GaInP) flanked by a gallium phosphide (GaP) segment. Daphnia mortality was assessed directly after 24 h of exposure and 7 days after exposure. Translocation of NWs across the intestinal epithelium was investigated using confocal fluorescence microscopy directly after 24 h of exposure and was observed in 89% of Daphnia exposed to 40 nm NWs and in 11% of Daphnia exposed to 80 nm NWs. A high degree of fragmentation was observed for NWs of both diameters after ingestion by the Daphnia, although 40 nm NWs were fragmented to a greater extent, which could possibly facilitate translocation across the intestinal epithelium. Our results show that the feeding behavior of animals may enhance the ability of NWs to penetrate biological barriers and that penetrance is governed by the NW diameter.


Assuntos
Daphnia/efeitos dos fármacos , Mucosa Intestinal/efeitos dos fármacos , Nanofios/toxicidade , Poluentes Químicos da Água/farmacocinética , Poluentes Químicos da Água/toxicidade , Animais , Transporte Biológico , Daphnia/metabolismo , Relação Dose-Resposta a Droga , Comportamento Alimentar/efeitos dos fármacos , Gálio/química , Índio/química , Mucosa Intestinal/metabolismo , Microscopia de Fluorescência , Nanofios/química , Tamanho da Partícula , Permeabilidade , Fosfinas/química , Propriedades de Superfície , Testes de Toxicidade , Poluentes Químicos da Água/química
17.
Nanotoxicology ; 10(2): 226-34, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26186033

RESUMO

Welding fumes include agglomerated particles built up of primary nanoparticles. Particles inhaled through the nose will to some extent be deposited in the protein-rich nasal mucosa, and a protein corona will be formed around the particles. The aim was to identify the protein corona formed between nasal lavage proteins and four types of particles with different parameters. Two of the particles were formed and collected during welding and two were manufactured iron oxides. When nasal lavage proteins were added to the particles, differences were observed in the sizes of the aggregates that were formed. Measurements showed that the amount of protein bound to particles correlated with the relative size increase of the aggregates, suggesting that the surface area was associated with the binding capacity. However, differences in aggregate sizes were detected when nasal proteins were added to UFWF and Fe2O3 particles (having similar agglomerated size) suggesting that yet parameters other than size determine the binding. Relative quantitative mass spectrometric and gel-based analyses showed differences in the protein content of the coronas. High-affinity proteins were further assessed for network interactions. Additional experiments showed that the inhibitory function of secretory leukocyte peptidase inhibitor, a highly abundant nasal protein, was influenced by particle binding suggesting that an understanding of protein function following particle binding is necessary to properly evaluate pathophysiological events. Our results underscore the importance of including particles collected from real working environments when studying the toxic effects of particles because these effects might be mediated by the protein corona.


Assuntos
Nanopartículas de Magnetita/química , Líquido da Lavagem Nasal/química , Coroa de Proteína/química , Soldagem , Humanos , Nanopartículas de Magnetita/ultraestrutura , Espectrometria de Massas , Tamanho da Partícula , Coroa de Proteína/análise , Inibidor Secretado de Peptidases Leucocitárias/metabolismo
18.
Mol Cancer ; 2: 18, 2003 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-12685933

RESUMO

BACKGROUND: p14ARF is a protein product of the alternative reading frame of the human INK4a locus. It functions as a tumor suppressor protein. p14ARF suppresses growth through p53-dependent and p53-independent pathways. RESULTS: p14ARF protein localizes primarily to the nucleoli. Here we show that in transfected cells p14ARF also appears in Hsp70 positive extranucleolar inclusions. The formation of p14ARF inclusions induces the parallel re-localization p53 and HDM2 to these sites that are also targeted by PML bodies and proteasomes. CONCLUSION: Our data show that co-localization between p53, HDM2 and p14ARF occurs at extranucleolar sites. Accumulation of PML and proteasomes at these sites suggest that the components of the nuclear inclusions are targeted for proteasome-mediated degradation.


Assuntos
Estruturas do Núcleo Celular/química , Cisteína Endopeptidases/metabolismo , Complexos Multienzimáticos/metabolismo , Proteínas Nucleares/análise , Proteína Supressora de Tumor p14ARF/análise , Animais , Linhagem Celular , Nucléolo Celular/química , Estruturas do Núcleo Celular/metabolismo , Proteínas de Choque Térmico HSP70/análise , Proteínas de Choque Térmico HSP70/metabolismo , Humanos , Camundongos , Microscopia de Fluorescência , Proteínas de Neoplasias/análise , Proteínas Nucleares/metabolismo , Proteína da Leucemia Promielocítica , Complexo de Endopeptidases do Proteassoma , Proteínas Proto-Oncogênicas/análise , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-mdm2 , Fatores de Transcrição/análise , Transfecção , Proteína Supressora de Tumor p14ARF/genética , Proteína Supressora de Tumor p14ARF/fisiologia , Proteína Supressora de Tumor p53/análise , Proteína Supressora de Tumor p53/metabolismo , Proteínas Supressoras de Tumor
19.
Immunol Lett ; 82(1-2): 141-7, 2002 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-12008045

RESUMO

The unique manifestation of the inherited immunodeficiency, X-linked lymphoproliferative disease (XLP), is the impaired control of EBV infection. The gene, which carries mutations or is deleted in the patients, has been identified (Xq25). The encoded protein (SAP, 128 aa) contains a single SH2 domain and binds to signaling lymphocytic activation molecule (SLAM) and to other related surface molecules that are expressed on activated T, B and NK cells. SAP modifies signal transduction through its association with these molecules. Initially it was assumed that SAP acts passively by interfering and blocking active interactions involving other SH2 carrying molecules. We demonstrated that SAP protein is expressed in activated T and NK, but not in activated B cells. This finding is in line with the fact that in vitro performance of effector cells derived from XLP patients is impaired. However, it is still not known why the severe symptoms (fatal mononucleosis or malignant lymphoproliferation in the survivors of the primary infection) are elicited by EBV. We studied SAP expression in several Burkitt lymphoma (BL) derived lines. In contrast to normal B cells, certain lines expressed SAP. These were all type I cells in the Burkitt line nomenclature: they expressed only one of the EBV encoded proteins (EBNA-1) and their phenotype corresponded to resting B cells. Lymphoblastoid cell lines and type III BLs, whose phenotype resembled activated B cells and expressed all nine EBV encoded proteins, were devoid of SAP. The relationship between cell activation and SAP expression is reciprocal in T and B cells i.e. BL lines, activated T and NK cells express SAP, while BL blasts do not express SAP. This opposite relationship may be exploited for studies about the function of SAP.


Assuntos
Proteínas de Transporte/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular , Células Matadoras Naturais/imunologia , Linfócitos T/imunologia , Antígenos CD , Linfócitos B/imunologia , Linfoma de Burkitt/imunologia , Transformação Celular Viral , Células Cultivadas , Ligação Genética , Glicoproteínas/análise , Herpesvirus Humano 4/patogenicidade , Humanos , Imunoglobulinas/análise , Mononucleose Infecciosa/imunologia , Células Jurkat , Ativação Linfocitária , Transtornos Linfoproliferativos/genética , Transtornos Linfoproliferativos/imunologia , Receptores de Superfície Celular , Proteína Associada à Molécula de Sinalização da Ativação Linfocitária , Membro 1 da Família de Moléculas de Sinalização da Ativação Linfocitária , Triexosilceramidas/análise , Células Tumorais Cultivadas , Cromossomo X
20.
Lakartidningen ; 99(50): 5095-7, 2002 Dec 12.
Artigo em Sueco | MEDLINE | ID: mdl-12572302

RESUMO

The article gives a clinically oriented overview of the efficacy and safety of Ginkgo biloba, St. John's wort, ginseng, Echinacea, saw palmetto and kava based on American experiences. Clinical data support the efficacy for some of these drugs. None of them is free of adverse effects. Generally speaking, trials of herbal medicinal products have been too few, too small and too short. The lack of long-term studies is especially unfortunate since many of the drugs are used for a long time. The difference between American and Swedish legislation on herbal medicine products is described.


Assuntos
Fitoterapia , Extratos Vegetais , Preparações de Plantas , Echinacea/efeitos adversos , Ginkgo biloba/efeitos adversos , Humanos , Hypericum/efeitos adversos , Kava/efeitos adversos , Conhecimento , Panax/efeitos adversos , Fitoterapia/efeitos adversos , Fitoterapia/estatística & dados numéricos , Extratos Vegetais/efeitos adversos , Extratos Vegetais/uso terapêutico , Preparações de Plantas/efeitos adversos , Preparações de Plantas/uso terapêutico
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