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1.
Environ Manage ; 74(3): 532-546, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38834791

RESUMO

Recreational angling of nesting largemouth bass (Micropterus nigricans) and smallmouth bass (M. dolomieu) can greatly increase nest abandonment, and in the northern clines of their range, decrease recruitment. This is the case in eastern Ontario, where high levels of non-compliance and difficult to enforce regulations have impacted black bass (Micropterus spp.) conservation and management. Effective January 1, 2024 until December 31st, 2025, novel and experimental fishing sanctuaries were imposed on portions of Charleston Lake and Opinicon Lake that prohibit recreational fishing of all types from April 15th to the Friday before the first Saturday in July (encompassing the full bass reproductive season). As part of the formal process to institute these experimental regulations, public comments were collected on the Environmental Registry of Ontario. We examined those comments and identified supportive and non-supportive themes related to these experimental regulations. While a majority of stakeholders were in support of the new regulations, we also noted sub-themes that may hinder regulation acceptance. Those sub-themes include: a perceived lack of enforcement negating the potential benefits of the sanctuaries, under-estimation of the extent of non-compliance with existing regulations such that new regulations are unnecessary, misunderstanding and misinformation, as well as distrust of government and the academic research community. Understanding and addressing these stakeholder perspectives will help researchers studying the new sanctuary areas and managers understand any lack of compliance while informing future decisions about bass management in eastern Ontario and beyond.


Assuntos
Bass , Conservação dos Recursos Naturais , Pesqueiros , Reprodução , Animais , Ontário , Conservação dos Recursos Naturais/legislação & jurisprudência , Conservação dos Recursos Naturais/métodos , Pesqueiros/legislação & jurisprudência , Opinião Pública
2.
Pediatr Radiol ; 53(6): 1076-1084, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36737516

RESUMO

BACKGROUND: The most common chronic complication of preterm birth is bronchopulmonary dysplasia (BPD), widely referred to as chronic lung disease of prematurity. All current definitions rely on characterizing the disease based on respiratory support level and do not provide full understanding of the underlying cardiopulmonary pathophysiology. OBJECTIVE: To evaluate a rapid functional lung imaging technique in premature infants and to quantitate pulmonary ventilation using 1.5 Tesla magnetic resonance imaging (MRI). MATERIALS AND METHODS: We conducted a prospective MRI study of 12 premature infants in the neonatal intensive care unit (NICU) using the phase resolved functional lung MRI technique to calculate pulmonary ventilation parameters in preterm infants with and without BPD grade 0/1 (n = 6) and grade 2/3 (n = 6). RESULTS: The total ventilation defect percentage showed a significant difference between groups (16.0% IQR (11.0%,18%) BPD grade 2/3 vs. 8.0% IQR (4.5%,9.0%) BPD grade 0/1, p = 0.01). CONCLUSION: Phase-resolved functional lung MRI is feasible for assessment of ventilation defect percentages in preterm infants and shows regional variation in localized lung function in this population.


Assuntos
Displasia Broncopulmonar , Nascimento Prematuro , Lactente , Feminino , Recém-Nascido , Humanos , Recém-Nascido Prematuro , Displasia Broncopulmonar/diagnóstico por imagem , Estudos Prospectivos , Pulmão/patologia , Imageamento por Ressonância Magnética/métodos
3.
NMR Biomed ; 32(6): e4088, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30908743

RESUMO

PURPOSE: To test the feasibility of regional fully quantitative ventilation measurement in free breathing derived by phase-resolved functional lung (PREFUL) MRI in the supine and prone positions. In addition, the influence of T2 * relaxation time on ventilation quantification is assessed. METHODS: Twelve healthy volunteers underwent functional MRI at 1.5 T using a 2D triple-echo spoiled gradient echo sequence allowing for quantitative measurement of T2 * relaxation time. Minute ventilation (ΔV) was quantified by conventional fractional ventilation (FV) and the newly introduced regional ventilation (VR), which corrects volume errors due to image registration. ΔVFV versus ΔVVR and ΔVVR versus ΔVVR with T2 * correction were compared using Bland-Altman plots and correlation analysis. The repeatability and physiological plausibility of all measurements were tested in the supine and prone positions. RESULTS: On global and regional scales a strong correlation was observed between ΔVFV versus ΔVVR and ΔVVR versus ΔVVRT2* (r > 0.93); however, regional Bland-Altman analysis showed systematic differences (p < 0.0001). Unlike ΔVVRT2* , ΔVVR and ΔVFV showed expected physiologic anterior-posterior gradients, which decreased in the supine but not in the prone position at second measurement during 3 min in the same position. For all quantification methods a moderate repeatability (coefficient of variation <20%) of ventilation was found. CONCLUSION: A fully quantified regional ventilation measurement using ΔVVR in free breathing is feasible and shows physiologically plausible results. In contrast to conventional ΔVFV, volume errors due to image registration are eliminated with the ΔVVR approach. However, correction for the T2 * effect remains challenging.


Assuntos
Pulmão/fisiologia , Imageamento por Ressonância Magnética , Ventilação Pulmonar/fisiologia , Respiração , Adulto , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Pulmão/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Postura , Reprodutibilidade dos Testes
4.
Pneumologie ; 73(10): 573-577, 2019 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-31537020

RESUMO

Substantial new data on early detection of lung cancer with low-dose CT has become available since the last joint statement of the German Roentgenological Society and the German Respiratory Society was published in 2011. The German S3 guideline on lung cancer was revised in 2018 and now contains a weak recommendation towards early detection of lung cancer with low-dose CT in a quality-assured early detection program. These new developments required a repositioning of the involved professional societies. This present joint statement describes main features of a quality-assured program for early detection of lung cancer with low-dose CT in Germany.


Assuntos
Detecção Precoce de Câncer , Neoplasias Pulmonares/diagnóstico por imagem , Proteção Radiológica/métodos , Proteção Radiológica/normas , Tomografia Computadorizada por Raios X/normas , Alemanha , Humanos , Guias de Prática Clínica como Assunto , Radiografia , Sociedades Médicas
5.
Am J Transplant ; 18(8): 2050-2060, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29607606

RESUMO

Chronic lung allograft dysfunction (CLAD) remains the leading cause of morbidity and mortality after lung transplantation. Diagnosis requires spirometric change, which becomes increasingly difficult with advancing CLAD. Fourier decomposition magnetic resonance imaging (FD-MRI) permits acquisition of ventilated-weighted images during free-breathing. This study evaluates FD-MRI in detecting CLAD in selected patients after bilateral lung transplantation (DLTx). DLTx recipients demonstrating CLAD at various stages participated. Radiologists remained blinded to clinical status until completion of image analysis. Image acquisition used a 1.5-T MR scanner using a spoiled gradient echo sequence. After FD processing and regional fractional ventilation (RFV) quantification, the volume defect percentage at 2 thresholds (VDP1,2 ), median lung RFV and quartile coefficient of dispersion (QCD) were calculated. Sixty-two patients participated. CLAD was present in 29/62 (47%) patients, of whom 17/62 (27%) had forced expiratory volume in 1 second ≤65% at image acquisition. VDP1 was higher among these participants compared to other groups (P < .001). Increased VDP1 was associated with subsequent graft loss, with values >2% showing reduced survival, independent of degree of graft dysfunction (P = .005). VDP2 discriminated between presence or absence of CLAD (area under the curve = 0.71; P = .03). QCD increased significantly with advancing disease (P < .001). In conclusion, FD-MRI-derived parameters demonstrate potential in quantitative CLAD diagnosis and assessment after DLTx.


Assuntos
Bronquiolite Obliterante/cirurgia , Rejeição de Enxerto/diagnóstico , Transplante de Pulmão/efeitos adversos , Imageamento por Ressonância Magnética/métodos , Complicações Pós-Operatórias , Disfunção Primária do Enxerto/diagnóstico , Adulto , Aloenxertos , Doença Crônica , Estudos Transversais , Feminino , Seguimentos , Rejeição de Enxerto/etiologia , Sobrevivência de Enxerto , Humanos , Masculino , Pessoa de Meia-Idade , Disfunção Primária do Enxerto/etiologia , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Adulto Jovem
6.
Analyst ; 141(11): 3367-78, 2016 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-27121177

RESUMO

For the first time, we combine pulsed electrodeposition with out-of-phase pulsed sonication for controlled synthesis of fractal nanoplatinum structures as the transducer layer in electrochemical sensing. We develop and test this technique, called bimodal pulsed sonoelectrodeposition (pulSED), as a simple approach for creating highly conductive transducer nanometals for use in sensing and biosensing. We first compared the efficiency of pulSED nanoplatinum to other pulsed electrodeposition techniques, and then explored the effect of duty cycle and plating time on electroactive surface area and nanoparticle size/morphology. The developed pulSED nanoplatinum displayed fractal features with a relatively homogenous size distribution (26.31 ± 1.3 nm) and extremely high electroactive surface (0.28 ± 0.04 cm(2)) relative to other electroplating techniques (up to one order of magnitude higher). A high duty cycle (900 mHz) promotes formation of stable nanostructures (including fractal nanostructures) and reduces amorphous structure formation due to bubble cavitation and enhanced mass transport of metal ions to the electrode surface. To demonstrate the applicability of the pulSED technique, non-enzymatic and enzymatic sensors were developed for measuring hydrogen peroxide and glucose. The sensitivity for non-enzymatic peroxide sensing (3335 ± 305 µA cm(-2) mM(-1)), non-enzymatic glucose sensing (73 ± 14 µA cm(-2) mM(-1)) and enzymatic glucose biosensing (155 ± 25 µA cm(-2) mM(-1)) was higher than, or similar to, other nanomaterial-mediated amperometric sensors reported in the literature. The pulSED technique is a one pot method for tunable synthesis of nanometal structures as a transducer layer in electrochemical sensing and biosensing that requires no precursors or capping agents, and can be carried out at room temperature with inexpensive hardware.


Assuntos
Técnicas Biossensoriais , Nanoestruturas , Platina , Técnicas Eletroquímicas , Eletrodos , Fractais , Glucose/análise , Peróxido de Hidrogênio/análise
7.
Pneumologie ; 70(12): 813-825, 2016 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-27931057

RESUMO

Technical innovation in pulmonary imaging during the recent years has led to a shift from morphological description of pulmonary pathologies to regional quantification of pulmonary function. This article summarizes current clinical standards in pulmonary imaging and introduces the reader to new innovative techniques of functional lung imaging. In the context of actual clinical studies for COPD, asthma, pulmonary hypertension and cystic fibrosis the application of quantitative imaging methods using computed tomography and magnetic resonance imaging is demonstrated and possible future applications are discussed.


Assuntos
Interpretação de Imagem Assistida por Computador/métodos , Pneumopatias/diagnóstico , Pneumopatias/patologia , Imageamento por Ressonância Magnética/métodos , Tomografia Computadorizada por Raios X/métodos , Angiografia/métodos , Humanos , Testes de Função Respiratória/métodos , Relação Ventilação-Perfusão
8.
Radiologe ; 54(12): 1147-52, 2014 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-25432870

RESUMO

BACKGROUND: The consensus classification of idiopathic interstitial pneumonia (IIP, also known as pulmonary fibrosis) in 2002 has undergone a significant revision in 2013. OBJECTIVES: What are the key points of the new consensus statement of the American Thoracic Society (ATS)/European Respiratory Society (ERS) from 2013 for the classification of pulmonary fibrosis? MATERIAL AND METHODS: Evaluation of the available literature on the subject of pulmonary fibrosis in Pubmed. RESULTS: The interdisciplinary approach (i.e. pulmonology, radiology and pathology) for the diagnosis of lung fibrosis subtypes is highlighted. Nonspecific interstitial pneumonia (NSIP) is now a separate specific form of pulmonary fibrosis. Smoking-associated respiratory bronchiolitis with interstitial lung disease (RB-ILD) is now frequently diagnosed without a lung biopsy on the basis of clinical findings, computed tomography and bronchoalveolar lavage. The heterogeneous course of idiopathic pulmonary fibrosis (IPF) is now recognized. The term "acute exacerbation" will now be used for acute attacks (< 30 days) in patients with chronic lung fibrosis (IPF and NSIP). It has been recognized that it is necessary to provide a clinical classification algorithm for the management of IIP cases. Pleuroparenchymal fibroelastosis (PPFE) is recognized as a rare new entity of pulmonary fibrosis. The rapidly evolving field of molecular markers is promising for improving the diagnostic approach. CONCLUSION: The 2013 ATS/ERS update is a supplement to the previous classification of lung fibrosis from 2002. It outlines progress in recent years and shows potential areas for future innovations.


Assuntos
Doenças Pulmonares Intersticiais/classificação , Doenças Pulmonares Intersticiais/diagnóstico , Guias de Prática Clínica como Assunto , Terminologia como Assunto , Tomografia Computadorizada por Raios X/normas , Humanos , Pneumologia/normas , Radiologia/normas , Estados Unidos
10.
Planta ; 238(3): 599-614, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23846103

RESUMO

Oxygen plays a critical role in plant metabolism, stress response/signaling, and adaptation to environmental changes (Lambers and Colmer, Plant Soil 274:7-15, 2005; Pitzschke et al., Antioxid Redox Signal 8:1757-1764, 2006; Van Breusegem et al., Plant Sci 161:405-414, 2001). Reactive oxygen species (ROS), by-products of various metabolic pathways in which oxygen is a key molecule, are produced during adaptation responses to environmental stress. While much is known about plant adaptation to stress (e.g., detoxifying enzymes, antioxidant production), the link between ROS metabolism, O2 transport, and stress response mechanisms is unknown. Thus, non-invasive technologies for measuring O2 are critical for understanding the link between physiological O2 transport and ROS signaling. New non-invasive technologies allow real-time measurement of O2 at the single cell and even organelle levels. This review briefly summarizes currently available (i.e., mainstream) technologies for measuring O2 and then introduces emerging technologies for measuring O2. Advanced techniques that provide the ability to non-invasively (i.e., non-destructively) measure O2 are highlighted. In the near future, these non-invasive sensors will facilitate novel experimentation that will allow plant physiologists to ask new hypothesis-driven research questions aimed at improving our understanding of physiological O2 transport.


Assuntos
Oxigênio/metabolismo , Plantas/metabolismo , Transporte Biológico/fisiologia , Fenômenos Fisiológicos Vegetais
11.
Opt Express ; 20(20): 22712-9, 2012 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-23037421

RESUMO

Using optoacoustic excitation, a complete volumetric tomographic data sets from the imaged object can in principle be generated with a single interrogating laser pulse. Thus, optoacoustic imaging intrinsically has the potential for fast three-dimensional imaging. We have developed a system capable of acquiring volumetric optoacoustic data in real time and showcase in this work the undocumented capacity to generate high resolution three-dimensional optoacoustic images at a rate of 10 Hz, currently mainly limited by the pulse repetition rate of the excitation laser.


Assuntos
Aumento da Imagem/instrumentação , Interpretação de Imagem Assistida por Computador/instrumentação , Imageamento Tridimensional/instrumentação , Técnicas Fotoacústicas/instrumentação , Gravação em Vídeo/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento
13.
Biotechnol Prog ; 34(1): 206-217, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28884510

RESUMO

Flavonoids are important value added products for dye sensitized solar cells biosensors, functional foods, medicinal supplements, nanomaterial synthesis, and other applications. Brassica oleracea contains high levels of anthocyanins in leaf sap vacuoles, and there are many viable extraction techniques that vary in terms of simplicity, environmental impact, cost, and extract photochemical/electrochemical properties. The efficiency of value added biotechnologies from flavonoid is a function of anthocyanin activity/concentration and molecule stability (i.e., ability to retain molecular resonance under a wide range of conditions). In this paper, we show that block cryoconcentration and partial thawing of anthocyanin from B. oleracea is a green, facile, and highly efficient technique that does not require any special equipment or protocols for producing enhanced value added products. Cryoconcentration increased anthocyanin activity and total phenol content approximately 10 times compared with common extraction techniques. Cryoconcentrated extract had enhanced electrochemical properties (higher oxidation potential), improved chroma, and higher UV absorbance than extract produced with other methods for a pH range of 2-12, with minimal effect on the diffusion coefficient of the extract. As a proof of concept for energy harvesting and sensor applications, dye sensitized solar cells and pH-sensitive thin films were prepared and tested. These devices were comparable with other recently published biotechnologies in terms of efficacy, but did not require expensive/environmentally detrimental extraction or concentration methods. This low cost, biorenewable, and simple method can be used for development of a variety of value added products. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 34:206-217, 2018.


Assuntos
Antocianinas/química , Criobiologia/métodos , Flavonoides/química , Extratos Vegetais/química , Técnicas Biossensoriais , Brassica/química , Folhas de Planta/química , Energia Solar
14.
Eur J Radiol ; 106: 137-144, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30150035

RESUMO

PURPOSE: To evaluate quantitative computed tomography (CT) measurements of the lung parenchyma in lung transplant (LTx) patients for early detection of the bronchiolitis obliterans syndrome (BOS). MATERIALS AND METHODS: 359 CT scans of 122 lung transplant patients were evaluated. Measurements of lung volume and density were performed for the whole lung and separately for each lobe. For longitudinal analysis the difference between the baseline at 6 months after LTx and follow-up examinations was calculated. Patients with and without BOS (matched 1:2) were compared at two different time points, the last examination before the BOS onset and the first examination within one year after BOS onset. RESULTS: 30 patients developed BOS during the follow-up period. Longitudinal changes in the lung volume and lung density measured on CT differed significantly between those patients with and without early BOS, in particular the difference of the inspiratory and expiratory lung volume (p < 0.001), the ratio of the expiratory and inspiratory lung volume (p < 0.001-p = 0.001) and MLD (p < 0.001-p = 0.001), the volume on expiration (p < 0.001-p = 0.007), the MLD on expiration (p < 0.001-p = 0.007), and the percentiles on expiration (p < 0.001-p = 0.002) with an increase of lung volume and a decrease of lung density. Changes were pronounced in the lower lobes. Before BOS onset, patients with and without future development of BOS showed no significant differences. CONCLUSION: Longitudinal changes of lung volume and lung density measured on CT start markedly at BOS onset with increased lung volume and decreased lung density indicating increased inflation levels. Even though this method may help to diagnose BOS at onset it is not useful as a predictor for BOS before disease onset.


Assuntos
Bronquiolite Obliterante/diagnóstico por imagem , Bronquiolite Obliterante/patologia , Transplante de Pulmão , Complicações Pós-Operatórias/diagnóstico por imagem , Complicações Pós-Operatórias/patologia , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Diagnóstico Precoce , Feminino , Humanos , Pulmão/diagnóstico por imagem , Pulmão/patologia , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Estudos Prospectivos , Adulto Jovem
15.
Biosens Bioelectron ; 85: 479-487, 2016 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-27209574

RESUMO

We demonstrate the first report of graphene paper functionalized with fractal platinum nanocauliflower for use in electrochemical biosensing of small molecules (glucose) or detection of pathogenic bacteria (Escherichia coli O157:H7). Raman spectroscopy, scanning electron microscopy and energy dispersive spectroscopy show that graphene oxide-coated nanocellulose was partially reduced by both thermal treatment, and further reduced by chemical treatment (ascorbic acid). Fractal nanoplatinum with cauliflower-like morphology was formed on the reduced graphene oxide paper using pulsed sonoelectrodeposition, producing a conductive paper with an extremely high electroactive surface area (0.29±0.13cm(2)), confirmed by cyclic voltammetry and electrochemical impedance spectroscopy. The platinum surface was functionalized with either glucose oxidase (via chitosan encapsulation) or a RNA aptamer (via covalent linking) for demonstration as a point of care biosensor. The detection limit for both glucose (0.08±0.02µM) and E. coli O157:H7 (≈4 CFUmL(-1)) were competitive with, or superior to, previously reported devices in the biosensing literature. The response time (6s for glucose and 12min for E. coli) were also similar to silicon biochip and commercial electrode sensors. The results demonstrate that the nanocellulose-graphene-nanoplatinum material is an excellent paper-based platform for development of electrochemical biosensors targeting small molecules or whole cells for use in point of care biosensing.


Assuntos
Técnicas Biossensoriais/métodos , Infecções por Escherichia coli/diagnóstico , Escherichia coli O157/isolamento & purificação , Glucose/análise , Grafite/química , Papel , Sistemas Automatizados de Assistência Junto ao Leito , Aptâmeros de Nucleotídeos/química , Glicemia/análise , Celulose/química , Celulose/ultraestrutura , Espectroscopia Dielétrica , Técnicas Eletroquímicas/métodos , Infecções por Escherichia coli/microbiologia , Glucose Oxidase/química , Humanos , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Platina/química
16.
Int J Radiat Oncol Biol Phys ; 49(3): 809-15, 2001 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-11172964

RESUMO

PURPOSE: To evaluate dose-dependent growth-modulating effects of the beta-gamma emitter Rhenium-188 on cultured human aortic smooth muscle cells (haSMC). METHODS AND MATERIALS: HaSMC were plated in 25 cm(2) flasks. Two days after plating, cells were incubated with the Re-188 (beta E(max) 2.12 MeV, tissue range(max) < 10 mm, T(1/2) 17 h) for five days. The doses administered were 0.2 Gy, 1, 4, 6, 8, 16, and 32 Gy. After five days, the radionuclide was removed. Cell growth, cell cycle distribution, and clonogenic activity were analyzed for the following 25 days. RESULTS: The 0.2 and 1 Gy groups did not show relevant growth-inhibiting effects compared to the control groups. The 4 to 32 Gy groups presented dose-dependent growth inhibition, with a complete growth arrest of the 16 and 32 Gy groups. Clonogenic activity of the smooth muscle cell was strongly inhibited from doses > or =8 Gy. Flow cytometry showed a lasting dose-dependent G2/M phase block. CONCLUSION: Smooth muscle cell (SMC) growth can be controlled effectively with Re-188 for at least 25 days after radiation in vitro. As the first four weeks after arterial angioplasty are crucial concerning neointimal formation, Re-188 may be a valuable radionuclide to inhibit restenosis after arterial angioplasty.


Assuntos
Aorta/efeitos da radiação , Divisão Celular/efeitos da radiação , Músculo Liso Vascular/efeitos da radiação , Radioisótopos/farmacologia , Rênio/farmacologia , Aorta/citologia , Relação Dose-Resposta a Droga , Humanos , Interfase/efeitos da radiação , Músculo Liso Vascular/citologia , Radiobiologia
17.
Dtsch Med Wochenschr ; 136(39): 1952-6, 2011 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-21935854

RESUMO

HISTORY AND ADMISSION FINDINGS: A 65-year-old woman presented with reduced general condition and dyspnoea that was progressive over the last months. Clinical findings revealed an exophthalmus on the right, xanthelasm and mild peripheral oedema. Previously, a pericardiocentesis had been performed due to a large pericardial effusion. A previous CT scan showed a mass attached to the pericardium extending through the atrio-ventricular groove and a thickened aorta. In addition, a retroperitoneal fibrosis and an occlusion of both Aa. iliacae internae were found. INVESTIGATIONS: The ECG showed sinus rhythm. Laboratory findings demonstrated a microcytic anemia and a renal failure. Chest radiography showed a large cardiac silhouette, while the transthoracic echocardiography revealed a recurrent large pericardial effusion. A PET/CT scan of the chest and abdomen showed a tissue infiltration of the retroperitoneal structures, a mass surrounding the right coronary artery and the right orbita. Finally, a femur biopsy confirmed the diagnosis of Erdheim-Chester disease. DIAGNOSIS, TREATMENT AND COURSE: With the diagnosis Erdheim-Chester disease we started a high dose immunsuppressive therapy using glucocorticoids and interferon-a. Tumour size slightly decreased during the following 2 months, however the patient developed a severe urosepsis and died from multiorgan failure. CONCLUSIONS: We report a case of an Erdheim-Chester disease with cardiovascular involvement primarily diagnosed due to a recurrent large pericardial effusion. In case of cardial tumors with interatrial septum or coronary artery involvement together with cerebral manifestations, an Erdheim-Chester disease should be taken into account.


Assuntos
Doença de Erdheim-Chester/complicações , Doença de Erdheim-Chester/diagnóstico , Derrame Pericárdico/diagnóstico , Derrame Pericárdico/etiologia , Diagnóstico Diferencial , Doença de Erdheim-Chester/tratamento farmacológico , Evolução Fatal , Feminino , Humanos , Imunossupressores/uso terapêutico , Pessoa de Meia-Idade , Derrame Pericárdico/tratamento farmacológico , Prevenção Secundária
18.
Biosens Bioelectron ; 26(5): 2237-45, 2011 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-20965716

RESUMO

Glucose is the central molecule in many biochemical pathways, and numerous approaches have been developed for fabricating micro biosensors designed to measure glucose concentration in/near cells and/or tissues. An inherent problem for microsensors used in physiological studies is a low signal-to-noise ratio, which is further complicated by concentration drift due to the metabolic activity of cells. A microsensor technique designed to filter extraneous electrical noise and provide direct quantification of active membrane transport is known as self-referencing. Self-referencing involves oscillation of a single microsensor via computer-controlled stepper motors within a stable gradient formed near cells/tissues (i.e., within the concentration boundary layer). The non-invasive technique provides direct measurement of trans-membrane (or trans-tissue) analyte flux. A glucose micro biosensor was fabricated using deposition of nanomaterials (platinum black, multiwalled carbon nanotubes, Nafion) and glucose oxidase on a platinum/iridium microelectrode. The highly sensitive/selective biosensor was used in the self-referencing modality for cell/tissue physiological transport studies. Detailed analysis of signal drift/noise filtering via phase sensitive detection (including a post-measurement analytical technique) are provided. Using this highly sensitive technique, physiological glucose uptake is demonstrated in a wide range of metabolic and pharmacological studies. Use of this technique is demonstrated for cancer cell physiology, bioenergetics, diabetes, and microbial biofilm physiology. This robust and versatile biosensor technique will provide much insight into biological transport in biomedical, environmental, and agricultural research applications.


Assuntos
Técnicas Biossensoriais/instrumentação , Membrana Celular/metabolismo , Condutometria/instrumentação , Glucose Oxidase/química , Glucose/metabolismo , Nanopartículas/química , Platina/química , Transporte Biológico Ativo/fisiologia , Sistemas Computacionais , Eletrodos , Enzimas Imobilizadas/química , Desenho de Equipamento , Análise de Falha de Equipamento , Miniaturização , Nanopartículas/ultraestrutura , Nanotecnologia/instrumentação
20.
J Neurosci Methods ; 189(1): 14-22, 2010 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-20298719

RESUMO

Quantification of neurotransmitter transport dynamics is hindered by a lack of sufficient tools to directly monitor bioactive flux under physiological conditions. Traditional techniques for studying neurotransmitter release/uptake require inferences from non-selective electrical recordings, are invasive/destructive, and/or suffer from poor temporal resolution. Recent advances in electrochemical biosensors have enhanced in vitro and in vivo detection of neurotransmitter concentration under physiological/pathophysiological conditions. The use of enzymatic biosensors with performance enhancing materials (e.g., carbon nanotubes) has been a major focus for many of these advances. However, these techniques are not used as mainstream neuroscience research tools, due to relatively low sensitivity, excessive drift/noise, low signal-to-noise ratio, and inability to quantify rapid neurochemical kinetics during synaptic transmission. A sensing technique known as self-referencing overcomes many of these problems, and allows non-invasive quantification of biophysical transport. This work presents a self-referencing CNT modified glutamate oxidase biosensor for monitoring glutamate flux near neural/neuronal cells. Concentration of basal glutamate was similar to other in vivo and in vitro measurements. The biosensor was used in self-referencing (oscillating) mode to measure net glutamate flux near neural cells during electrical stimulation. Prior to stimulation, the average influx was 33.9+/-6.4 fmol cm(-2)s(-1)). Glutamate efflux took place immediately following stimulation, and was always followed by uptake in the 50-150 fmol cm(-2)s(-1) range. Uptake was inhibited using threo-beta-benzyloxyaspartate, and average surface flux in replicate cells (1.1+/-7.4 fmol cm(-2)s(-1)) was significantly lower than uninhibited cells. The technique is extremely valuable for studying neuropathological conditions related to neurotransmission under dynamic physiological conditions.


Assuntos
Técnicas Biossensoriais/instrumentação , Química Encefálica/fisiologia , Eletrofisiologia/instrumentação , Ácido Glutâmico/metabolismo , Neuroquímica/instrumentação , Neurônios/metabolismo , Animais , Ácido Aspártico/farmacologia , Transporte Biológico Ativo/fisiologia , Técnicas Biossensoriais/métodos , Células Cultivadas , Estimulação Elétrica , Eletrofisiologia/métodos , Ácido Glutâmico/análise , Camundongos , Neuroquímica/métodos , Oxirredutases/química , Tempo de Reação/fisiologia , Transmissão Sináptica/fisiologia , Fatores de Tempo
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