O presente trabalho foi apoiado pelo Programa Europeu IST União (Project &quot;INTREPID - A Virtual Reality Sistema Multi-sensor inteligente para Tratamento de Fobias Wearable&quot; - IST-2002-507464).

O protocolo clínico para o tratamento do Transtorno de Ansiedade Generalizada (TAG) é programado simultaneamente dentro e fora do escritório do terapeuta. Programa de relaxamento é uma combinação de &quot;Formação de Relaxamento Muscular Progressivo&quot; (PMRT), o procedimento clássico descrito por Jacobsen, que envolve tensão e relaxar vários grupos musculares ao mesmo tempo tomando nota das sensações contrastantes, e &quot;Guided Imagery&quot; do programa. No nosso imaginário treinamento é substituída pela indicação visual de um ambiente relaxante virtual. DENTRO consultório do terapeuta. Pacientes participam a 8 sessões de treinamento com o terapeuta, distribuídos em quatro semanas (2 sessões por semana). Cada sessão começa e termina com uma avaliação clínica que dá a medida da ansiedade do paciente. Plano de sessões no consultório do terapeuta: <ol><li> Avaliação clínica inicial do estado do paciente; </li><li> O paciente é conectado com biossensores que gravar seu / sua parâmetros fisiológicos (condutância da pele, freqüência cardíaca, a respiração). A medida de referência destes parâmetros é registrada por 3 minutos; </li><li> O paciente usa um display head-mounted ligada a um pc e lida com um joystick; </li><li> O paciente começa a explorar o ambiente virtual: uma bela ilha tropical enfrenta no oceano. O paciente, após a narrativa gravada pelo terapeuta, atinge a ilha de barco e explorá-lo. Seguindo uma trilha que orienta ele / ela através da ilha, o paciente chega ao ponto de partida, onde os painéis diferentes indicam as direções para as áreas-alvo diferente. Em cada uma dessas áreas um exercício de relaxamento é proporcionada, durante esta formação, seguindo as indicações dadas pela voz-guia, o paciente tenta relaxar ele / ela mesma, enquanto alguns elementos do ambiente virtual são modificadas diretamente por seu / sua parâmetros fisiológicos registrados em tempo real. Assim, o paciente recebe um feedback imediato da sua / seu nível de ativação (como nas técnicas de biofeedback tradicional), mas com o valor extra dado pelo ambiente virtual que ele / ela é immersively explorar. As áreas-alvo são obrigados a: <ul><li> Campfire: parâmetros fisiológicos controlar a intensidade do fogo, de modo que a redução dos resultados do paciente ativação fisiológica sobre a redução do fogo até que ele sai; </li><li> Waves: parâmetros fisiológicos controlar as ondas até o oceano torna-se completamente calmo; </li><li> Cachoeira: a redução do estímulo fisiológico corresponde a uma redução da intensidade de corrente até que a água pára de cair. </li><li> Gazebo: diferentemente dos outros, este exercício é personalizável pelo paciente, que podem escolher palavras ou imagens relacionadas a ele / ela pessoais eventos estressantes. Esta técnica serve como um programa de inoculação do estresse, eo paciente pode experimentar a redução no tamanho-fading flutuante do item escolhido - em função da sua / sua capacidade de relaxar ele / ela mesma; </li></ul></li><li> Uma vez concluída a sessão de realidade virtual, parâmetros fisiológicos são registrados novamente em condição de repouso; </li><li> Avaliação clínica final do estado do paciente. </li></ol> ESCRITÓRIO FORA DO TERAPEUTA: A fim de melhorar a eficácia da formação e aumentar os efeitos de relaxamento, os pacientes vai praticar técnicas de relaxamento fora do escritório do terapeuta, experimentando um cenário de Homecare. Isto é realizado através da apresentação do mesmo ambiente virtual experientes durante a terapia em um dispositivo móvel. O dispositivo móvel é conectado via Bluetooth a um conjunto de biossensores que inclui taxas de coração e condutância da pele. Este equipamento é pequeno o suficiente e fácil de usar para ser tratado de forma autônoma pelo paciente (vide fig. 1). O paciente é necessário para treinar habilidades de relaxamento pelo menos uma vez por dia, durante toda a duração do tratamento (um mês), seguindo o plano de tratamento fornecidas pelo terapeuta. Resultados representante Porque ambos biofeedback e realidade virtual são conhecidos para ser eficaz para induzir o relaxamento, o principal resultado esperado é que uma combinação desses dois métodos é mais eficaz na redução da ansiedade em pacientes afetados por transtorno de ansiedade generalizada, do que as duas técnicas utilizadas individualmente. <img src="/files/ftp_upload/1554/Fig1.jpg" alt="Figura 1" /> Figura 1: GSR / HR módulo de biossensores.

<ol>
	<li>Arntz, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cognitive+therapy+versus+applied+relaxation+as+treatment+of+generalized+anxiety+disorder.">Cognitive therapy versus applied relaxation as treatment of generalized anxiety disorder.</a> Behav Res Ther. 41 (6), 633-633 (2003).</li><li>Siev, J., Chambless, D. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Specificity+of+treatment+effects:+cognitive+therapy+and+relaxation+for+generalized+anxiety+and+panic+disorders.">Specificity of treatment effects: cognitive therapy and relaxation for generalized anxiety and panic disorders.</a> Journal of consulting and clinical psychology. 75 (4), 513-513 (2007).</li><li>Jacobsen, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Progressive relaxation. , (1938).</li><li>Villani, D., Riva, F., Riva, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=New+technologies+for+relaxation:+the+role+of+presence.">New technologies for relaxation: the role of presence.</a> International journal of Stress Management. 14 (3), 260-260 (2007).</li></ol>

The authors have nothing to disclose.

Nossa hipótese é que a combinação de realidade virtual e biofeedback que diretamente modifica o ambiente virtual, em comparação com a realidade virtual sozinho, irá resultar em um relaxamento melhor e mais rápido aprendizado. Se assim for, este novo instrumento criado para tratar transtornos de ansiedade poderia ser aplicado e testado mesmo em outras patologias relacionados à ansiedade.

the use of biofeedback in clinical virtual reality: the intrepid project

Transtorno de ansiedade generalizada (TAG) é um transtorno psiquiátrico caracterizado por uma constante ansiedade e inespecíficos que interfere com atividades da vida diária. Sua alta prevalência na população em geral e as limitações graves, causas, apontam a necessidade de encontrar novas estratégias eficientes para tratá-la. Juntamente com os tratamentos cognitivo-comportamental, relaxamento representa uma abordagem útil para o tratamento da GAD, mas tem a limitação que é difícil de ser aprendida. O projeto INTREPID visa implementar um novo instrumento para tratar a ansiedade e distúrbios relacionados para testar a sua eficácia clínica na redução da ansiedade relacionada com os sintomas. A inovação desta abordagem é a combinação de realidade virtual e biofeedback, de modo que o primeiro está diretamente modificada pela saída do segundo. Desta forma, o paciente está ciente de suas reações através da modificação de algumas características do ambiente VR em tempo real. Utilizando exercícios mentais que o paciente aprende a controlar estes parâmetros fisiológicos e usar o feedback fornecido pelo ambiente virtual é capaz de medir o sucesso dele ou dela. O uso suplementar de dispositivos portáteis, como PDA ou smart-phones, permite que o paciente a realizar em casa, individualmente e de forma autônoma, os mesmos exercícios com experiência em escritório terapeuta. O objetivo é ancorar o protocolo aprendido em um contexto de vida real, assim aumentando a capacidade dos pacientes para lidar com seus sintomas. O resultado esperado é uma melhor e mais rápido aprendizado de técnicas de relaxamento, e, assim, uma maior eficácia do tratamento, se comparado com os tradicionais protocolos clínicos.

Watch this Scientific Journal Video about The use of Biofeedback in Clinical Virtual Reality: The INTREPID Project at JoVE.com

The use of Biofeedback in Clinical Virtual Reality: The INTREPID Project

Projeto sobre Realidade Virtual Sistema Multi-sensor inteligente para o tratamento da ansiedade relacionada com Disorders (Intrepid) visa o desenvolvimento de um sensor multi-sensíveis ao contexto do sistema de realidade virtual para o tratamento de distúrbios relacionados a ansiedade.

O uso de Biofeedback na Clínica de Realidade Virtual: O Projeto INTREPID

Generalized anxiety disorder (GAD) is a psychiatric disorder characterized by a constant and unspecific anxiety that interferes with daily-life ...

the-use-biofeedback-clinical-virtual-reality-intrepid

Research

JoVE Journal

Biology

15.1K visualizações.  Istituto Auxologico Italiano. Projeto sobre Realidade Virtual Sistema Multi-sensor inteligente para o tratamento da ansiedade relacionada com Disorders (Intrepid) visa o desenvolvimento de um sensor multi-sensíveis ao contexto do sistema de realidade virtual para o tratamento de distúrbios relacionados a ansiedade.

Vídeo: The use of Biofeedback in Clinical Virtual Reality: The INTREPID Project

Use of Rotorod as a Method for the Qualitative Analysis of Walking in Rat

High speed videoanalysis of the details of movement can provide a source of information about qualitative aspects of walking movements. When walking on a rotorod, animals remain in approximately the same place making repetitive movements of stepping. Thus the task provides a rich source of information on the details of foot stepping movements. Subjects were hemi-Parkinson analogue rats, produced by injection of 6-hydroxydopamine (6-OHDA) into the right nigrostriatal bundle to deplete nigrostriatal dopamine (DA). The present report provides a video analysis illustration of animals previously were filmed from frontal, lateral, and posterior views as they walked (15). Rating scales and frame-by-frame replay of the video records of stepping behavior indicated that the hemi-Parkinson rats were chronically impaired in posture and limb use contralateral to the DA-depletion. The contralateral limbs participated less in initiating and sustaining propulsion than the ipsilateral limbs. These deficits secondary to unilateral DA-depletion show that the rotorod provides a use task for the analysis of stepping movements.

The rotorod test is used to assess motor status in the walking movement of hemi-Parkinson analogue rats.

Uso de Rotorod como um método de análise qualitativa de Walking in Rat

High speed videoanalysis of the details of movement can provide a source of information about qualitative aspects of walking movements. When walking on a ...

Biologia

Psychophysiological Stress Assessment Using Biofeedback 

In the last half century, research in biofeedback has shown the extent to which the human mind can influence the functioning of the autonomic nervous system, previously thought to be outside of conscious control. By letting people observe signals from their own bodies, biofeedback enables them to develop greater awareness of their physiological and psychological reactions, such as stress, and to learn to modify these reactions. Biofeedback practitioners can facilitate this process by assessing people s reactions to mildly stressful events and formulating a biofeedback-based treatment plan. During stress assessment the practitioner first records a baseline for physiological readings, and then presents the client with several mild stressors, such as a cognitive, physical and emotional stressor. Variety of stressors is presented in order to determine a person's stimulus-response specificity, or differences in each person's reaction to qualitatively different stimuli. This video will demonstrate the process of psychophysiological stress assessment using biofeedback and present general guidelines for treatment planning.

Psychophysiological Stress Assessment Using Biofeedback

In this video we will describe one method of assessing person's psychophysiological reaction to stress using biofeedback. We will also present general guidelines for treatment planning.

Avaliação do estresse psicofisiológico Usando Biofeedback

In the last half century, research in biofeedback has shown the extent to which the human mind can influence the functioning of the autonomic nervous ...

The use of SC1 (Pluripotin) to Support mESC Self-renewal in the Absence of LIF

Mouse embryonic stem (ES) cells are conventionally cultured with Leukemia Inhibitory Factor (LIF) to maintain self-renewal.1 However, LIF is expensive and activation of the LIF/JAK/STAT3 pathway is not absolutely required to maintain the self-renewal state.2 The SC1 small molecule may be an economical alternative to LIF. SC1 functions through dual inhibition of Ras-GAP and ERK1.3 Illustration of its mechanism of action makes it a useful tool to study the fundamental molecular mechanism of self-renewal. Here we demonstrate the procedure for culturing mouse ES cells in the presence of SC1 and show that they are able to maintain self-renewal in the absence of LIF. Cells cultured with SC1 showed similar morphology compared to cells maintained with LIF. Both exhibited typical mouse ES morphology after five passages. Expression of typical pluripotency markers (Oct4, Sox2, Nanog, and SSEA1) was observed after five passages in the presence of SC1. Furthermore, SC1 caused no overt toxicity on mouse ES cells.

The use of SC1 Pluripotin to Support mESC Self-renewal in the Absence of LIF

SC1 functions through dual inhibition of Ras- GAP and ERK1. We tested the function of SC1 in supporting mouse ES cell self-renewal in the absence of LIF and showed that SC1 is able to maintain self-renewal of mouse ES cell cultures.

O uso de SC1 (Pluripotin) para Suporte MESC auto-renovação na ausência de LIF

Mouse embryonic stem (ES) cells are conventionally cultured with Leukemia Inhibitory Factor (LIF) to maintain self-renewal.1 However, LIF is expensive and ...

Purification of the M. magneticum Strain AMB-1 Magnetosome Associated Protein MamA&Delta;41

Magnetotactic bacteria comprise a diverse group of aquatic microorganisms that are able to orientate themselves along geomagnetic fields. This behavior is believed to aid their search for suitable environments (1). This capability is conferred by the magnetosome, a subcellular organelle that consists of a linear-chain assembly of lipid vesicles each able to biomineralize and enclose a ~50-nm crystal of magnetite or greigite. A principle component of the magnetosome that was shown to be required for the formation of functional vesicles is MamA. MamA is a highly abundant magnetosome-associated protein which is one of the most characterized magnetosome-associated proteins in vivo (2-6). This article focuses on the purification of MamA, which despite being studied in vivo, no clear functional or structural details have been identified for it. Bioinformatics analysis suggested that MamA is a tetra-tricopeptide repeat (TPR) containing protein. TPR is a structural motif found as such or forming part of a bigger fold in a wide range of proteins, it serves as a template for protein-protein interactions and mediates multi-protein complexes (7). TPRs are involved in many crucial tasks in eukaryotic cell organelle processes and many bacterial pathways (8-14). In order to understand MamA, a unique TPR containing protein, highly purified protein is required as a first step. In this article, we present the purification protocol for a stable MamA deletion mutant (MamA&Delta;41) from M. magneticum AMB-1.

Purification of the &lt;em&gt;M. magneticum&lt;/em&gt; Strain AMB-1 Magnetosome Associated Protein MamA&amp;Delta;41

MamA is a unique Magnetosome associated protein which was shown to be involved in magnetosome activation. Here we present the purification protocol of MamA deletion mutant (MamA&Delta;41) from M. magneticum AMB-1.

Purificação do M. magneticum Strain AMB-1 proteína associada Magnetosome MamAΔ41

Magnetotactic bacteria comprise a diverse group of aquatic microorganisms that are able to orientate themselves along geomagnetic fields. This behavior is ...

Live Imaging of Apoptotic Cell Clearance during Drosophila Embryogenesis

The proper elimination of unwanted or aberrant cells through apoptosis and subsequent phagocytosis (apoptotic cell clearance) is crucial for normal development in all metazoan organisms. Apoptotic cell clearance is a highly dynamic process intimately associated with cell death; unengulfed apoptotic cells are barely seen in vivo under normal conditions. In order to understand the different steps of apoptotic cell clearance and to compare 'professional' phagocytes - macrophages and dendritic cells to 'non-professional' - tissue-resident neighboring cells, in vivo live imaging of the process is extremely valuable. Here we describe a protocol for studying apoptotic cell clearance in live Drosophila embryos. To follow the dynamics of different steps in phagocytosis we use specific markers for apoptotic cells and phagocytes. In addition, we can monitor two phagocyte systems in parallel: 'professional' macrophages and 'semi-professional' glia in the developing central nervous system (CNS). The method described here employs the Drosophila embryo as an excellent model for real time studies of apoptotic cell clearance.

Live Imaging of Apoptotic Cell Clearance during Drosophila Embryogenesis

Here we describe an effective method for studying dynamics of apoptotic cell clearance in vivo. This method employs live Drosophila embryos as a powerful model for monitoring phagocytosis of apoptotic cells using specific labeling of apoptotic cells and phagocytes.

Imagens ao vivo de Apuramento celular por apoptose durante<em&gt; Drosophila</em&gt; Embriogênese

The  proper elimination of unwanted or aberrant cells through apoptosis and  subsequent phagocytosis (apoptotic cell clearance) is crucial for normal  ...

The Use of Chemostats in Microbial Systems Biology

Cells regulate their rate of growth in response to signals from the external world. As the cell grows, diverse cellular processes must be coordinated including macromolecular synthesis, metabolism and ultimately, commitment to the cell division cycle. The chemostat, a method of experimentally controlling cell growth rate, provides a powerful means of systematically studying how growth rate impacts cellular processes - including gene expression and metabolism - and the regulatory networks that control the rate of cell growth. When maintained for hundreds of generations chemostats can be used to study adaptive evolution of microbes in environmental conditions that limit cell growth. We describe the principle of chemostat cultures, demonstrate their operation and provide examples of their various applications. Following a period of disuse after their introduction in the middle of the twentieth century, the convergence of genome-scale methodologies with a renewed interest in the regulation of cell growth and the molecular basis of adaptive evolution is stimulating a renaissance in the use of chemostats in biological research.

Cell growth rate is a regulated process and a primary determinant of cell physiology. Continuous culturing using chemostats enables extrinsic control of cell growth rate by nutrient limitation facilitating the study of molecular networks that control cell growth and how those networks evolve to optimize cell growth.

O Uso de quimiostatos em Microbial Biologia de Sistemas

Cells regulate their rate of growth in response to signals from the external world. As the cell grows, diverse cellular processes must be coordinated ...

Culturing of Human Nasal Epithelial Cells at the Air Liquid Interface

In vitro models using human primary epithelial cells are essential in understanding key functions of the respiratory epithelium in the context of microbial infections or inhaled agents. Direct comparisons of cells obtained from diseased populations allow us to characterize different phenotypes and dissect the underlying mechanisms mediating changes in epithelial cell function. Culturing epithelial cells from the human tracheobronchial region has been well documented, but is limited by the availability of human lung tissue or invasiveness associated with obtaining the bronchial brushes biopsies. Nasal epithelial cells are obtained through much less invasive superficial nasal scrape biopsies and subjects can be biopsied multiple times with no significant side effects. Additionally, the nose is the entry point to the respiratory system and therefore one of the first sites to be exposed to any kind of air-borne stressor, such as microbial agents, pollutants, or allergens. 
Briefly, nasal epithelial cells obtained from human volunteers are expanded on coated tissue culture plates, and then transferred onto cell culture inserts. Upon reaching confluency, cells continue to be cultured at the air-liquid interface (ALI), for several weeks, which creates more physiologically relevant conditions. The ALI culture condition uses defined media leading to a differentiated epithelium that exhibits morphological and functional characteristics similar to the human nasal epithelium, with both ciliated and mucus producing cells. Tissue culture inserts with differentiated nasal epithelial cells can be manipulated in a variety of ways depending on the research questions (treatment with pharmacological agents, transduction with lentiviral vectors, exposure to gases, or infection with microbial agents) and analyzed for numerous different endpoints ranging from cellular and molecular pathways, functional changes, morphology, etc. 
In vitro models of differentiated human nasal epithelial cells will enable investigators to address novel and important research questions by using organotypic experimental models that largely mimic the nasal epithelium in vivo.

Nasal epithelial cells, obtained through superficial scrape biopsy of human volunteers, are expanded and transferred onto tissue culture inserts. Upon reaching confluency, cells are grown at air liquid interface, yielding cultures of ciliated and non-ciliated cells. Differentiated nasal epithelial cell cultures provide viable experimental models for studying the respiratory mucosa.

A cultura de células epiteliais nasais Humano na interface ar líquido

In vitro models using human primary  epithelial cells are essential in understanding key functions of the respiratory  epithelium in the context of ...

Using Caenorhabditis elegans as a Model System to Study Protein Homeostasis in a Multicellular Organism

The folding and assembly of proteins is essential for protein function, the long-term health of the cell, and longevity of the organism. Historically, the function and regulation of protein folding was studied in vitro, in isolated tissue culture cells and in unicellular organisms. Recent studies have uncovered links between protein homeostasis (proteostasis), metabolism, development, aging, and temperature-sensing. These findings have led to the development of new tools for monitoring protein folding in the model metazoan organism Caenorhabditis elegans. In our laboratory, we combine behavioral assays, imaging and biochemical approaches using temperature-sensitive or naturally occurring metastable proteins as sensors of the folding environment to monitor protein misfolding. Behavioral assays that are associated with the misfolding of a specific protein provide a simple and powerful readout for protein folding, allowing for the fast screening of genes and conditions that modulate folding. Likewise, such misfolding can be associated with protein mislocalization in the cell. Monitoring protein localization can, therefore, highlight changes in cellular folding capacity occurring in different tissues, at various stages of development and in the face of changing conditions. Finally, using biochemical tools ex vivo, we can directly monitor protein stability and conformation. Thus, by combining behavioral assays, imaging and biochemical techniques, we are able to monitor protein misfolding at the resolution of the organism, the cell, and the protein, respectively.

Using Caenorhabditis elegans as a Model System to Study Protein Homeostasis in a Multicellular Organism

To study the relationship between protein homeostasis, stress and aging, we monitored changes in protein folding by following protein dysfunction, protein localization in the cell and protein stability at the organismal, cellular and protein levels, using the genetically tractable metazoan Caenorhabditis elegans as a model system.

The folding and assembly of proteins is essential for protein function, the long-term health of the cell, and longevity of the organism. Historically, the ...

Probe-based Real-time PCR Approaches for Quantitative Measurement of microRNAs

Probe-based quantitative PCR (qPCR) is a favoured method for measuring transcript abundance, since it is one of the most sensitive detection methods that provides an accurate and reproducible analysis. Probe-based chemistry offers the least background fluorescence as compared to other (dye-based) chemistries. Presently, there are several platforms available that use probe-based chemistry to quantitate transcript abundance. qPCR in a 96 well plate is the most routinely used method, however only a maximum of 96 samples or miRNAs can be tested in a single run. This is time-consuming and tedious if a large number of samples/miRNAs are to be analyzed. High-throughput probe-based platforms such as microfluidics (e.g. TaqMan Array Card) and nanofluidics arrays (e.g. OpenArray) offer ease to reproducibly and efficiently detect the abundance of multiple microRNAs in a large number of samples in a short time. Here, we demonstrate the experimental setup and protocol for miRNA quantitation from serum or plasma-EDTA samples, using probe-based chemistry and three different platforms (96 well plate, microfluidics and nanofluidics arrays) offering increasing levels of throughput.

Circulating microRNAs have recently emerged as promising and novel biomarkers for various cancers and other diseases. The goal of this article is to discuss three different probe-based real-time PCR platforms and methods that are available to quantify and determine the abundance of circulating microRNAs.

Baseado-Probe-PCR em tempo real Abordagens para a medição quantitativa de microRNAs

Probe-based quantitative PCR (qPCR) is a favoured method for measuring transcript abundance, since it is one of the most sensitive detection methods that ...

Use of Enzymatic Biosensors to Quantify Endogenous ATP or H2O2 in the Kidney

Enzymatic microelectrode biosensors have been widely used to measure extracellular signaling in real-time. Most of their use has been limited to brain slices and neuronal cell cultures. Recently, this technology has been applied to the whole organs. Advances in sensor design have made &#160;possible the measuring of&#160;cell signaling in blood-perfused in vivo kidneys. The present protocols list the steps needed to measure ATP and H2O2 signaling in the rat kidney interstitium. Two separate sensor designs are used for the ex vivo and in vivo protocols. Both types of sensor&#160;are coated with&#160;a thin enzymatic biolayer on top of a permselectivity layer to give fast responding, sensitive and selective biosensors. The permselectivity layer protects the signal from the interferents in biological tissue, and the enzymatic layer utilizes&#160;the sequential catalytic reaction of glycerol kinase and glycerol-3-phosphate oxidase in the presence of ATP to produce H2O2. The set of sensors used for the ex vivo studies further detected analyte by oxidation of H2O2 on a platinum/iridium (Pt-Ir) wire electrode. The sensors for the&#160;in vivo studies are instead based on the reduction of H2O2 on a mediator coated gold electrode designed for blood-perfused tissue. Final concentration changes&#160;are detected by real-time amperometry followed by calibration to known concentrations of analyte. Additionally, the specificity of the amperometric signal can be confirmed by the addition of enzymes such as catalase and apyrase that break down H2O2 and ATP correspondingly. These sensors also rely heavily on accurate calibrations before and after each experiment. The following two protocols establish the study of real-time detection of ATP and H2O2 in kidney tissues, and can be further modified to extend the described method for use in other biological preparations or whole organs.

Use of Enzymatic Biosensors to Quantify Endogenous ATP or H2O2 in the Kidney

Enzymatic microelectrode biosensors enable real-time measurements of extracellular cell signaling in biologically-relevant concentrations. The following protocols extend the applications of biosensors to the ex vivo and in vivo detection of ATP and H2O2 in the kidney.

Uso de biossensores para quantificar enzimática endógena ATP ou H<sub&gt; 2</sub&gt; Ó<sub&gt; 2</sub&gt; No rim

Enzymatic microelectrode biosensors have been widely used to measure extracellular signaling in real-time. Most of their use has been limited to brain ...