Agradecemos a drs. John Hancock, Ray Grill, Andrew Morris e Olga Chumakova pelo seu apoio. O FlexStation 3 sistema faz parte do Mecanismo de imagem UTHSC Cytodynamic. Agradecemos também os drs. Ardem Patapoutian e Michael Bandell do Scripps Research Institute e Instituto de Genômica da Novartis Research Foundation (GNF) para fornecer a linha de células-HEK293 hTRPA1 estável. A pesquisa é financiada em parte por concessões do NIH (GM081658 para MXZ) e Texas Medical Center Digestive Diseases Center (para HH) e Missão Connect / TIRR Foundation (para HH).

1. Preparações de células em placas de 96 poços Para HEK293 células transitoriamente trasfected com TRPA1 humana cDNA <ol><li> HEK293 células são cultivadas para 1-2 dias em meio mínimo essencial de Dulbecco (DMEM), contendo 4,5 glicose mg / ml (Thermo Scientific, SH3002201), suplementado com inativado pelo calor de 10% de soro fetal bovino (Invitrogen, 16000-044), 50 unidades / ml de penicilina e estreptomicina 50 mg / ml (Invitrogen, 15140-163). No dia da transfecção, a densidade celular deve chegar a 70-90%. </li><li> Casaco de placas de 96 poços pipetando 50 ul poli-L-ornitina (Sigma P3655, 20 mcg / ml em água destilada estéril) a cada poço e incubar a 37 ° C por pelo menos 15 min. Enxágüe bem cada vez com fosfato Dulbecco Buffered Saline (DPBS) sem Mg 2 + e Ca 2 + (Thermo Scientific, SH3002803). A placa pode ser deixado na capa de cultura de células por algumas horas. </li><li> Para cada poço de uma placa de 96 poços, diluir em um tubo Eppendorf de 1,5 ml 0,2 mg em 25 mL de cDNA OPTI-MEM (Invitrogen, 31985-070). Escala até proporcionalmente de acordo com o número de poços a serem transfectadas pelo cDNA mesmo. Também diluir em um de 1,5 ml Eppendorf separados Lipofectamine tubo de 0,4 mL de 2000 (Invitrogen, 11668-019) em 25 mL OPTI-MEM para cada poço a ser transfectadas. Escala esta de acordo com o número total de poços a serem transfectadas. </li><li> Brevemente vórtice de 2000 cDNA diluído e Lipofectamine e deixá-los sentar-se à temperatura ambiente por cerca de 5 min. </li><li> Transferência de um volume igual do Lipofectamine diluída 2000 para o tubo que contém as diluída vortex, cDNA e deixe a mistura descansar em temperatura ambiente por 15 min a 2 horas. Durante este tempo, transfira o cDNA / 2000 Lipofectamine mistura de 49 mL / poço da placa poli-L-ornitina revestido. </li><li> Trypsinize o HEK293 células (Passo 1.1), contagem de densidade celular utilizando um hemocitômetro ou Condessa contador de células automatizado (Invitrogen, C10227), e transferência de uma quantidade desejada de células (geralmente cerca de ~ 125,000-150,000 células / poço) para uma solução estéril de 15 ml cônico-bottom tubo de centrifugação. Centrifugar a 1000 RPM x por 5 min. Ressuspender as células em ~ 1,250,00-1,500,000 células / ml no meio de cultura DMEM, suplementado com 10% inativado pelo calor soro fetal bovino, mas sem antibióticos. </li><li> Dispense 98 mL suspensão celular a cada poço que contém o cDNA-Lipofectamine 2000 mistura usando uma pipeta multicanal ou o Dispenser Microplate micropartículas (Bio-Tek). Deixe a placa de sentar-se na capa de pelo menos 30 minutos antes de colocá-lo à cultura de células umidificado incubadora. Incubar a 37 ° CO C, 5% 2 para 20-44 hrs. </li></ol> Para HEK293 células expressando estavelmente TRPA1 <ol start="8"><li> Siga o passo 1,2 para revestir placas de 96 poços. </li><li> A linha induzível HEK293-hTRPA1 celular foi generosamente fornecida pelo Dr. A. Patapoutian (The Scripps Research Institute) e mantidos no mesmo meio como o tipo selvagem HEK293 células (Passo 1.1), mas suplementado com 5 mg / ml blasticidin (Invitrogen, A1113902) e 50 mg / ml higromicina B (Invitrogen, 10687010). Quando a densidade de células atinge cerca de 90%, trypsinize células, contagem e densidade das células, e centrifugar a quantidade desejada de células em 1000 x RPM por 5 min. Ressuspender as células em uma densidade de aproximadamente 1.000.000 células / ml no mesmo meio de cultura suplementado com doxiciclina (Fisher, BP26535, 0,25 mg / ml). </li><li> Dispensar a suspensão de células poli-L-ornitina placas revestidas em 100 l / poço usando uma pipeta multicanal ou a micropartículas (Bio-Tek). Deixe a placa de sentar-se na capa de pelo menos 30 minutos antes de colocá-lo à cultura de células umidificado incubadora. Incubar a 37 ° C, 5% de CO 2 para 16-24 hr. </li></ol> 2. Soluções <ol><li> Solução de Hank sal tamponado (HBSS) é usado como a solução extracelular. Ele contém (em mM): 137 NaCl, 5,4 KCl, 0,25 Na 2 HPO 4, 0,44 KH 2 PO 4, 1,3 CaCl 2, MgSO 4 1,0, 1,0 MgCl 2, 10 de glicose, 10 HEPES, com pH ajustado para 7,4 com NaOH 1N). </li><li> Fluo-4 tampão de ensaio contém 2 mM probenecide, em HBSS. Fazer 250 mM de ações probenecida (Sigma, P8761) em 0,5 N NaOH. Diluir a HBSS na proporção de 1:125. Reajuste pH a 7,4 usando HCl 1 N. </li></ol> 3. Carregar celular com Fluo-04:00 <ol><li> Dissolver 1 mg Fluo-04:00 (Invitrogen, F14202) em 912 mL DMSO anidro para fazer uma solução estoque de 1 mM. A Fluo-4:00 solução estoque pode ser armazenado a -20 ° C durante pelo menos um mês. </li><li> Mix 10 mM 1 ml Fluo-04:00 com 10 mL PLURONIC F-127 (Invitrogen, P3000MP, 20% (w / v) em solução de DMSO) e depois transferir todo o conteúdo de 5 ml tampão de ensaio Fluo-4 (Passo 2.2) suplementado com 0,1% albumina bovina (Sigma, A9418). </li><li> Lave as células cultivadas em placas de 96 poços (Passo 1.7 ou 1.10) com HBSS a 80 mL / poço duas vezes usando um lavador de microplacas (como ELx405TM de Bio-Tek). </li><li> Adicione o Fluo-4 AM carregamento solução (Passo 3.2) a 50 mL / poço usando uma pipeta multicanal ou a micropartículas (Bio-Tek) e incube a placa a 37 ° C por 1 hora. </li><li> Lave as células 3 vezes com o tampão de ensaio Fluo-4 (Passo 2.2.) Utilizando o lavador de microplacas ELx405TM. Após a última lavagem, deixar 80 l do tampão Fluo-4 do ensaio em cada poço. </li></ol> 4. Preparação do prato composto <ol><li> Durante o período de uma célula de carga hr, preparar uma série de diluições 3x de agonistas (ou antagonistas) de 3x da concentração final desejada no buffer Fluo-4 ensaio. </li><li> Pipeta 250-300 mL das soluções diluídas composto de um prato composto de 96 poços. Providenciar para que as diluições de série de um composto e os controles positivos e negativos correspondentes na mesma coluna da placa composto sempre que for possível porque FlexStation 3 lê uma única coluna de cada vez. </li></ol> 5. Leitura da placa em três FlexStation <ol><li> Ligue o sistema (FlexStation 3, computador, eo software SoftMax Pro 5.2) </li><li> Salvar o experimento com um novo nome de arquivo. No set-up, escolher o modo de FLEX e digite os seguintes valores: </li></ol> Protocolo n º 1, efeito agonista <img src="/files/ftp_upload/3149/3149table1.jpg" alt="Tabela 1" /> Protocolo n º 2, efeito antagonista <img src="/files/ftp_upload/3149/3149table2.jpg" alt="Tabela 2" /><ol start="3"><li> Coloque uma caixa nova ponta, prato composto ea placa de leitura para as bandejas apropriadas em FlexStation 3 e clique em &quot;ler&quot; botão. O FlexStation 3 vai ler uma coluna de cada vez e adicione compostos nos pontos de tempo pré-programado, sem interromper a leitura. Demora cerca de 3 min (5 min para o Protocolo n º 2) para terminar de ler uma coluna ea máquina irá continuar a ler a próxima coluna composto com adições realizadas como programado pelo usuário no passo 5.2 até que todas as colunas são lidas. </li></ol> 6. Análise de dados <ol><li> Dados experimentais podem ser processados ​​diretamente usando a SoftMax Pro 5.2 software ou copiado e colado em qualquer programa de planilha eletrônica, como Microsoft Excel. Curva de concentração-resposta de um ácido flufenâmico TRPA1 agonista (FFA) é construído usando a rotina de montagem seguintes mínimos quadrados. <img src="/files/ftp_upload/3149/3149eq1.jpg" alt="Equação 1" /> , Onde Y é a resposta observada, Y max é a resposta normalizada máxima, C é a concentração do medicamento correspondente, EC 50 é a concentração que provocou uma resposta meia-máxima, e n H é o coeficiente de Monte aparente. Concentração de inibição da curva para um composto antagonista do suposto TRPA1 A é obtida utilizando uma concentração fixa de FFA (100 mM), e, progressivamente, aumentando a concentração do composto A. IC 50 valor do composto A é calculado pelo ajuste dos mínimos quadrados para o seguinte equação. <img src="/files/ftp_upload/3149/3149eq2.jpg" alt="Equação 2" /> , Onde Y é a resposta observada e Y max é normalizado pico de resposta, [Ant] é o composto correspondente A concentração, o IC 50 é a concentração antagonista que produz metade máxima inibição da FFA evocadas resposta, e n H é o monte aparente coeficiente. </li></ol> 7. Resultados representativos: TRPA1 é um canal de Ca 2 + cátion-permeável, a activação do que leva a influxo de cálcio que pode ser detectado pelo Ca 2 + sensíveis ao corante, Fluo-4 (1-2). A linhagem de células-HEK293 hTRPA1 estável foi usado para estudar as relações concentração-resposta de TRPA1 agonistas e antagonistas. Células foram carregadas com Fluo-04:00, colocados em 80 mL do tampão de ensaio, e ler usando FlexStation 3. Depois de gravar a fluorescência de base por 30 s, 40 mL de uma diluição em série do agonista TRPA1, FFA, cada um em 3x de a concentração desejada final, foram adicionados às células através de uma pipeta multi-canal incluído como parte do módulo de fluidos de FlexStation 3. As mudanças de fluorescência foram monitorados por mais 180 s. As mudanças em relação Fluo-4 fluorescência para cada poço foram expressos como ΔF = (F - F 0), onde 0 F e F são valores de fluorescência no momento de interesse eo início da leitura, respectivamente. Traços representante dos cursos tempo para mudanças de fluorescência em resposta a uma série de concentrações de FFA são mostrados na fig. 1. Nota para os últimos quatro concentrações de AGL, embora os níveis de resposta máxima são semelhantes, a cinética de ativação é claramente mais rápido no ponto mais alto do que na menor concentração de AGL. Portanto, para distinguir estas diferenças, a concentração - relação de resposta foi construída através da medição da taxas iniciais (inclinação) do aumento de fluorescência com a adição de concentrações variadas de FFA (Fig. 2). O efeito máximo meiaive concentração (EC 50) de AGL foi determinada como sendo 55,4 mM (n = 3). Para testar o antagonista TRPA1 putativo, composto A, que realizou um experimento similar, usando o protocolo de número 2 (Passo 2). Neste caso, uma série de diluições do antagonista foram adicionados em 30 s (40 mL de 3x desejado concentrações finais) eo FFA foi adicionado 180 s mais tarde (60 mL em 300 M para uma concentração final de 100 mM). Composto A dose-dependente reduziu a resposta da TRPA1 células para FFA com uma concentração máxima meia inibitória (IC 50) de 4,3 mM (n = 3) (Fig. 2). <img src="/files/ftp_upload/3149/3149fig1.jpg" alt="Figura 1"/> Figura 1. Activação dependente da concentração de TRPA1 humanos por FFA. Traços são aumentar FFA evocadas de fluorescência ao longo do tempo (respostas só nos primeiros 60 s são mostradas para ilustrar melhor a cinética rápida das respostas evocadas FFA). Por favor note que em concentrações mais elevadas FFA evocado aumento de fluorescência com um. Muito mais rápido do que cinética em concentrações mais baixas, embora os níveis de pico de fluorescência foram semelhantes <img src="/files/ftp_upload/3149/3149fig2.jpg" alt="Figura 2"/> Figura 2 Concentração -. Relacionamentos resposta para FFA mudanças induzidas pelo fluorescência e composto A-induzida inibição da resposta em FFA TRPA1 humano de forma estável, expresso em HEK293 células. Δ, a concentração - relação de resposta de AGL foi determinada pela medição da taxa inicial (inclinação) do aumento de fluorescência normalizada com a adição de diferentes concentrações de AGL. O, concentração-resposta relação de inibição da FFA-resposta evocada por um antagonista do cálcio TRPA1 putativo, composto A.

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Ca 2 + intracelular desempenha um papel importante em muitas condições fisiológicas e patológicas, como a liberação de neurotransmissores (3), potencial de ação cardíaco (4), a contração da célula muscular (5), transdução de sinal celular (6-7), e morte celular excitotoxic ( 8). Medição de Ca 2 + intracelular níveis ajuda a elucidar as alterações funcionais de Ca 2 +-permeável canais na membrana plasmática ou organelas intracelulares ea contribuição de Ca <s...

<table border="1"><tbody><tr><th> Nome do reagente </th><th> Companhia </th><th> Número de catálogo </th><th> Comentários (opcional) </th></tr><tr><td> FlexStation 3 </td><td> Os dispositivos moleculares </td><td> FLEX3 </td><td></td></tr><tr><td> 96-Bem, Pipetar Dicas FlexStation </td><td> Os dispositivos moleculares </td><td> 9000-0912 </td><td></td></tr><tr><td> Placas de 96 poços </td><td> Greiner Bio-one </td><td> 655090 </td><td></td></tr><tr><td> 96-Bem Limpar plano placas inferior </td><td> Costar </td><td> 3595 </td><td></td></tr><tr><td> DMEM </td><td> Invitrogen </td><td> 12430-104 </td><td></td></tr><tr><td> Opti-MEM </td><td> Invitrogen </td><td> 31985-070 </td><td></td></tr><tr><td> Lipofectamine 2000 </td><td> Invitrogen </td><td> 11668-019 </td><td></td></tr><tr><td> Fluo-04:00 </td><td> Invitrogen </td><td> F14202 </td><td></td></tr><tr><td> PluronicF-127 </td><td> Invitrogen </td><td> P3000MP </td><td></td></tr><tr><td> Poli-L-ornitina </td><td> Sigma </td><td> P36551 </td><td></td></tr><tr><td> probenecid </td><td> Sigma </td><td> P8761 </td><td></td></tr><tr><td> Albumina de soro bovino </td><td> Sigma </td><td> A9418 </td><td></td></tr></tbody></table>

cell-based calcium assay for medium to high throughput screening of trp channel functions using flexstation 3

FlexStation Dispositivos Molecular &#39;3 é uma bancada modo multi-leitor de microplacas capaz de medição de fluorescência automatizado em multi-lamelas. É ideal para empresas de médio a alto rendimento telas em ambientes acadêmicos. Ele tem um módulo de transferência integrada de fluido equipado com uma pipeta multi-canal ea máquina lê uma coluna de cada vez para monitorar as mudanças de fluorescência de uma variedade de reagentes fluorescentes. Por exemplo, FlexStation 3 tem sido usado para estudar a função de Ca 2 +-permeável canais iônicos e G receptores acoplados à proteína, medindo as mudanças de livre intracelular Ca 2 + níveis. Transiente potencial receptor (TRP) canais são uma grande família de canais de comunicação não-seletivos que desempenham papéis importantes em muitas funções fisiológicas e fisiopatológicas. A maioria dos canais de cálcio TRP são permeáveis ​​e induzir o influxo de cálcio na ativação. Neste vídeo, demonstramos a aplicação de FlexStation 3 a estudar o perfil farmacológico do canal TRPA1, um sensor molecular para inúmeros estímulos nocivos. HEK293 células transitoriamente ou expressando estavelmente humana TRPA1 canais, cultivadas em placas de 96 poços, são carregados com um Ca 2 + sensíveis ao corante fluorescente, Fluo-4, e em tempo real as mudanças de fluorescência nessas células são medidos antes e durante a aplicação de um agonista TRPA1 usando o modo FLEX do FlexStation 3. O efeito de um antagonista TRPA1 putativa também foi examinada. Dados são transferidos do software Pro SoftMax para construir relações concentração-resposta de TRPA1 ativadores e inibidores.

Watch this Scientific Journal Video about Cell-based Calcium Assay for Medium to High Throughput Screening of TRP Channel Functions using FlexStation 3 at JoVE.com

Cell-based Calcium Assay for Medium to High Throughput Screening of TRP Channel Functions using FlexStation 3

Este vídeo fornece um protocolo detalhado para o estudo do perfil farmacológico dos direitos humanos TRPA1 canais usando FlexStation 3. O protocolo abrange detalhes de preparação das células, carregando corante e operação do leitor de microplacas, FlexStation 3.

Baseados em células de Ensaio de cálcio para Médio a High Throughput Screening de Funções TRP usando FlexStation Canal 3

The Molecular Devices' FlexStation 3 is a benchtop multi-mode microplate reader capable of automated fluorescence measurement in multi-well plates.  It is ...

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21.0K visualizações.  The University of Texas Health Science Center at Houston. Este vídeo fornece um protocolo detalhado para o estudo do perfil farmacológico dos direitos humanos TRPA1 canais usando FlexStation 3. O protocolo abrange detalhes de preparação das células, carregando corante e operação do leitor de microplacas, FlexStation 3.

Vídeo: Cell-based Calcium Assay for Medium to High Throughput Screening of TRP Channel Functions using FlexStation 3

Polymer Microarrays for High Throughput Discovery of Biomaterials

The discovery of novel biomaterials that are optimized for a specific biological application is readily achieved using polymer microarrays, which allows a combinatorial library of materials to be screened in a parallel, high throughput format1. Herein is described the formation and characterization of a polymer microarray using an on-chip photopolymerization technique 2. This involves mixing monomers at varied ratios to produce a library of monomer solutions, transferring the solution to a glass slide format using a robotic printing device and curing with UV irradiation. This format is readily amenable to many biological assays, including stem cell attachment and proliferation, cell sorting and low bacterial adhesion, allowing the ready identification of 'hit' materials that fulfill a specific biological criterion3-5. Furthermore, the use of high throughput surface characterization (HTSC) allows the biological performance to be correlated with physio-chemical properties, hence elucidating the biological-material interaction6. HTSC makes use of water contact angle (WCA) measurements, atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS). In particular, ToF-SIMS provides a chemically rich analysis of the sample that can be used to correlate the cell response with a molecular moiety. In some cases, the biological performance can be predicted from the ToF-SIMS spectra, demonstrating the chemical dependence of a biological-material interaction, and informing the development of hit materials5,3.

A description of the formation of a polymer microarray using an on-chip photopolymerization technique. The high throughput surface characterization using atomic force microscopy, water contact angle measurements, X-ray photoelectron spectroscopy and time of flight secondary ion mass spectrometry and a cell attachment assay is also described.

Microarrays de polímeros para Discovery High Throughput de Biomateriais

The discovery of novel biomaterials that are optimized for a specific biological application is readily achieved using polymer microarrays, which allows a ...

Bioengenharia

Candida albicans Biofilm Chip (CaBChip) for High-throughput Antifungal Drug Screening

Candida albicans remains the main etiological agent of candidiasis, which currently represents the fourth most common nosocomial bloodstream infection in US hospitals1. These opportunistic infections pose a growing threat for an increasing number of compromised individuals, and carry unacceptably high mortality rates. This is in part due to the limited arsenal of antifungal drugs, but also to the emergence of resistance against the most commonly used antifungal agents. Further complicating treatment is the fact that a majority of manifestations of candidiasis are associated with the formation of biofilms, and cells within these biofilms show increased levels of resistance to most clinically-used antifungal agents2. Here we describe the development of a high-density microarray that consists of C. albicans nano-biofilms, which we have named CaBChip3. Briefly, a robotic microarrayer is used to print yeast cells of C. albicans onto a solid substrate. During printing, the yeast cells are enclosed in a three dimensional matrix using a volume as low as 50 nL and immobilized on a glass substrate with a suitable coating. After initial printing, the slides are incubated at 37 &deg;C for 24 hours to allow for biofilm development. During this period the spots grow into fully developed "nano-biofilms" that display typical structural and phenotypic characteristics associated with mature C. albicans biofilms (i.e. morphological complexity, three dimensional architecture and drug resistance)4. Overall, the CaBChip is composed of ~750 equivalent and spatially distinct biofilms; with the additional advantage that multiple chips can be printed and processed simultaneously. Cell viability is estimated by measuring the fluorescent intensity of FUN1 metabolic stain using a microarray scanner. This fungal chip is ideally suited for use in true high-throughput screening for antifungal drug discovery. Compared to current standards (i.e. the 96-well microtiter plate model of biofilm formation5), the main advantages of the fungal biofilm chip are automation, miniaturization, savings in amount and cost of reagents and analyses time, as well as the elimination of labor intensive steps. We believe that such chip will significantly speed up the antifungal drug discovery process.

Candida albicans Biofilm Chip CaBChip for High-throughput Antifungal Drug Screening

We have developed a high-density microarray platform consisting of 3D nano-biofilms of C. albicans called CaBChip. The susceptibility profile of drugs tested on a CaBChip is comparable to the conventional 96-well plate model, suggesting that the fungal chip is ideally suited for true high-throughput screening of antifungal drugs.

Candida albicans biofilme Chip (Ca BChip) para seleção de alto rendimento antifúngico

Candida  albicans remains the main etiological agent of candidiasis, which  currently represents the fourth most common nosocomial bloodstream infection ...

High-throughput Protein Expression Generator Using a Microfluidic Platform

Rapidly increasing fields, such as systems biology, require the development and implementation of new technologies, enabling high-throughput and high-fidelity measurements of large systems. Microfluidics promises to fulfill many of these requirements, such as performing high-throughput screening experiments on-chip, encompassing biochemical, biophysical, and cell-based assays1. Since the early days of microfluidics devices, this field has drastically evolved, leading to the development of microfluidic large-scale integration2,3. This technology allows for the integration of thousands of micromechanical valves on a single device with a postage-sized footprint (Figure 1). We have developed a high-throughput microfluidic platform for generating in vitro expression of protein arrays (Figure 2) named PING (Protein Interaction Network Generator). These arrays can serve as a template for many experiments such as protein-protein 4, protein-RNA5 or protein-DNA6 interactions.
The device consist of thousands of reaction chambers, which are individually programmed using a microarrayer. Aligning of these printed microarrays to microfluidics devices programs each chamber with a single spot eliminating potential contamination or cross-reactivity Moreover, generating microarrays using standard microarray spotting techniques is also very modular, allowing for the arraying of proteins7, DNA8, small molecules, and even colloidal suspensions. The potential impact of microfluidics on biological sciences is significant. A number of microfluidics based assays have already provided novel insights into the structure and function of biological systems, and the field of microfluidics will continue to impact biology.

We present a microfluidic approach for the expression of protein arrays. The device consists of thousands of reaction chambers controlled by micro-mechanical valves. The microfluidic device is mated to a microarray-printed gene library. These genes are then transcribed and translated on-chip, resulting in a protein array ready for experimental use.

Alto rendimento Gerador Protein Expression Usando uma plataforma microfluídica

Rapidly increasing fields, such as systems biology, require the development and implementation of new technologies, enabling high-throughput and ...

Generation of Scalable, Metallic High-Aspect Ratio Nanocomposites in a Biological Liquid Medium

The goal of this protocol is to describe the synthesis of two novel biocomposites with high-aspect ratio structures. The biocomposites consist of copper and cystine, with either copper nanoparticles (CNPs) or copper sulfate contributing the metallic component. Synthesis is carried out in liquid under biological conditions (37 &#176;C) and the self-assembled composites form after 24 hr. Once formed, these composites are highly stable in both liquid media and in a dried form. The composites scale from the nano- to micro- range in length, and from a few microns to 25 nm in diameter. Field emission scanning electron microscopy with energy dispersive X-ray spectroscopy (EDX) demonstrated that sulfur was present in the NP-derived linear structures, while it was absent from the starting CNP material, thus confirming cystine as the source of sulfur in the final nanocomposites. During synthesis of these linear nano- and micro-composites, a diverse range of lengths of structures is formed in the synthesis vessel. Sonication of the liquid mixture after synthesis was demonstrated to assist in controlling average size of the structures by diminishing the average length with increased time of sonication. Since the formed structures are highly stable, do not agglomerate, and are formed in liquid phase, centrifugation may also be used to assist in concentrating and segregating formed composites.

Here we present a protocol to synthesize novel, high-aspect ratio biocomposites under biological conditions and in liquid media. The biocomposites scale from nanometers to micrometers in diameter and length, respectively. Copper nanoparticles (CNPs) and copper sulfate combined with cystine are the key components for the synthesis.

Geração de escalável e de alto-Aspect Metallic nanocompósitos índices, em um Biológico Líquido Médio

The goal of this protocol is to describe the synthesis of two novel biocomposites with high-aspect ratio structures. The biocomposites consist of copper ...

Using Tomoauto: A Protocol for High-throughput Automated Cryo-electron Tomography

Cryo-electron tomography (Cryo-ET) is a powerful three-dimensional (3-D) imaging technique for visualizing macromolecular complexes in their native context at a molecular level. The technique involves initially preserving the sample in its native state by rapidly freezing the specimen in vitreous ice, then collecting a series of micrographs from different angles at high magnification, and finally computationally reconstructing a 3-D density map. The frozen-hydrated specimen is extremely sensitive to the electron beam and so micrographs are collected at very low electron doses to limit the radiation damage. As a result, the raw cryo-tomogram has a very low signal to noise ratio characterized by an intrinsically noisy image. To better visualize subjects of interest, conventional imaging analysis and sub-tomogram averaging in which sub-tomograms of the subject are extracted from the initial tomogram and aligned and averaged are utilized to improve both contrast and resolution. Large datasets of tilt-series are essential to understanding and resolving the complexes at different states, conditions, or mutations as well as obtaining a large enough collection of sub-tomograms for averaging and classification. Collecting and processing this data can be a major obstacle preventing further analysis. Here we describe a high-throughput cryo-ET protocol based on a computer-controlled 300kV cryo-electron microscope, a direct detection device (DDD) camera and a highly effective, semi-automated image-processing pipeline software wrapper library tomoauto developed in-house. This protocol has been effectively utilized to visualize the intact type III secretion system (T3SS) in Shigella flexneri minicells. It can be applicable to any project suitable for cryo-ET.

We present a protocol on how to utilize high-throughput cryo-electron tomography to determine high resolution in situ structures of molecular machines. The protocol permits large amounts of data to be processed, avoids common bottlenecks and reduces resource downtime, allowing the user to focus on important biological questions.

Usando Tomoauto: Um Protocolo de métodos de alta capacidade automatizada Cryo-Electron Tomografia

Cryo-electron tomography (Cryo-ET) is a powerful three-dimensional (3-D) imaging technique for visualizing macromolecular complexes in their native ...

High-throughput Identification of Bacteria Repellent Polymers for Medical Devices

Medical devices are often associated with hospital-acquired infections, which place enormous strain on patients and the healthcare system as well as contributing to antimicrobial resistance. One possible avenue for the reduction of device-associated infections is the identification of bacteria-repellent polymer coatings for these devices, which would prevent bacterial binding at the initial attachment step. A method for the identification of such repellent polymers, based on the parallel screening of hundreds of polymers using a microarray, is described here. This high-throughput method resulted in the identification of a range of promising polymers that resisted binding of various clinically relevant bacterial species individually and also as multi-species communities. One polymer, PA13 (poly(methylmethacrylate-co-dimethylacrylamide)), demonstrated significant reduction in attachment of a number of hospital isolates when coated onto two commercially available central venous catheters. The method described could be applied to identify polymers for a wide range of applications in which modification of bacterial attachment is important.

A high-throughput microarray method for the identification of polymers which reduce bacterial surface binding on medical devices is described.

High-throughput identificação de bactérias Polymers Repelente para dispositivos médicos

Medical devices are often associated with hospital-acquired infections, which place enormous strain on patients and the healthcare system as well as ...

3D Microtissues for Injectable Regenerative Therapy and High-throughput Drug Screening

To upgrade traditional 2D cell culture to 3D cell culture, we have integrated microfabrication with cryogelation technology to produce macroporous microscale cryogels (microcryogels), which can be loaded with a variety of cell types to form 3D microtissues. Herein, we present the protocol to fabricate versatile 3D microtissues and their applications in regenerative therapy and drug screening. Size and shape-controllable microcryogels can be fabricated on an array chip, which can be harvested off-chip as individual cell-loaded carriers for injectable regenerative therapy or be further assembled on-chip into 3D microtissue arrays for high-throughput drug screening. Due to the high elastic nature of these microscale cryogels, the 3D microtissues exhibit great injectability for minimally invasive cell therapy by protecting cells from mechanical shear force during injection. This ensures enhanced cell survival and therapeutic effect in the mouse limb ischemia model. Meanwhile, assembly of 3D microtissue arrays in a standard 384-multi-well format facilitates the use of common laboratory facilities and equipment, enabling high-throughput drug screening on this versatile 3D cell culture platform.

This protocol describes the fabrication of elastic 3D macroporous microcryogels by integrating microfabrication with cryogelation technology. Upon loading with cells, 3D microtissues are generated, which can be readily injected in vivo to facilitate regenerative therapy or assembled into arrays for in vitro high-throughput drug screening.

Microtissues 3D para terapia regenerativa injetável e triagem de drogas de alto rendimento

To upgrade traditional 2D cell culture to 3D cell culture, we have integrated microfabrication with cryogelation technology to produce macroporous ...

Process Optimization using High Throughput Automated Micro-Bioreactors in Chinese Hamster Ovary Cell Cultivation

Optimization of bioprocesses to increase the yield of desired products is of importance in the biopharmaceutical industry. This can be achieved by strain selection and by developing bioprocess parameters. Shake flasks have been used for this purpose. They, however, lack the capability to control the process parameters such as pH and dissolved oxygen (DO). This limitation can be overcome with the help of an automated micro-bioreactor. These bioreactors mimic cultivation at a larger scale. One of the major advantages of this system is the integration of the Design of Experiment (DOE) in the software. This integration enables establishing a design where multiple process parameters can be varied simultaneously. The critical process parameters and optimum bioprocess conditions can be analyzed within the software. The focus of the work presented here is to introduce the user to the steps involved in process design in the software and incorporation of the DOE within the cultivation run.

Here, we present a detailed procedure to run a Design of Experiment in an automated micro-bioreactor followed by cell harvest and protein quantification using a Protein A column.

Otimização de processos usando micro-bioreatores automatizados de alto throughput no cultivo de células de ovário de hamster chinês

Optimization of bioprocesses to increase the yield of desired products is of importance in the biopharmaceutical industry. This can be achieved by strain ...

High-Throughput Identification of Resistance to Pseudomonas syringae pv. Tomato in Tomato using Seedling Flood Assay

Tomato is an agronomically important crop that can be infected by Pseudomonas syringae, a Gram-negative bacterium, resulting in bacterial speck disease. The tomato-P. syringae pv. tomato pathosystem is widely used to dissect the genetic basis of plant innate responses and disease resistance. While disease was successfully managed for many decades through the introduction of the Pto/Prf gene cluster from Solanum pimpinellifolium into cultivated tomato, race 1 strains of P. syringae have evolved to overcome resistance conferred by the Pto/Prf gene cluster and occur worldwide.
Wild tomato species are important reservoirs of natural diversity in pathogen recognition, because they evolved in diverse environments with different pathogen pressures. In typical screens for disease resistance in wild tomato, adult plants are used, which can limit the number of plants that can be screened due to their extended growth time and greater growth space requirements. We developed a method to screen 10-day-old tomato seedlings for resistance, which minimizes plant growth time and growth chamber space, allows a rapid turnover of plants, and allows large sample sizes to be tested. Seedling outcomes of survival or death can be treated as discrete phenotypes or on a resistance scale defined by amount of new growth in surviving seedlings after flooding. This method has been optimized to screen 10-day-old tomato seedlings for resistance to two P. syringae strains and can easily be adapted to other P. syringae strains.

High-Throughput Identification of Resistance to Pseudomonas syringae pv. Tomato in Tomato using Seedling Flood Assay

The seedling flood assay facilitates rapid screening of wild tomato accessions for the resistance to the Pseudomonas syringae bacterium. This assay, used in conjunction with the seedling bacterial growth assay, can assist in further characterizing the underlying resistance to the bacterium, and can be used to screen mapping populations to determine the genetic basis of resistance.

Identificação de alta duração da resistência a Pseudomonas syringae pv. Tomate no Tomate usando Ensaio de Inundação de Mudas

Tomato is an agronomically important crop that can be infected by Pseudomonas syringae, a Gram-negative bacterium, resulting in bacterial speck disease. ...

Generation of Dynamical Environmental Conditions using a High-Throughput Microfluidic Device

Mimicking in vivo environmental conditions is crucial for in vitro studies on complex life machinery. However, current techniques targeting live cells and organs are either highly expensive, like robotics, or lack nanoliter volume and millisecond time accuracy in liquid manipulation. We herein present the design and fabrication of a microfluidic system, which consists of 1,500 culture units, an array of enhanced peristaltic pumps and an on-site mixing modulus. To demonstrate the capacities of the microfluidic device, neural stem cell (NSC) spheres are maintained in the proposed system. We observed that when the NSC sphere is exposed to CXCL in day 1 and EGF in day 2, the round-shaped conformation is well maintained. Variation in the input order of 6 drugs causes morphological changes to the NSC sphere and the expression level representative marker for NSC stemness (i.e., Hes5 and Dcx). These results indicate that dynamic and complex environmental conditions have great effects on NSC differentiation and self-renewal, and the proposed microfluidic device is a suitable platform for high throughput studies on the complex life machinery.

We present a microfluidic system for high throughput studies on complex life machinery, which consists of 1500 culture units, an array of enhanced peristaltic pumps and an on-site mixing modulus. The microfluidic chip allows for the analysis of the highly complex and dynamic micro-environmental conditions in vivo.

Geração de Condições Ambientais Dinâmicas usando um dispositivo microfluido de alto rendimento

Mimicking in vivo environmental conditions is crucial for in vitro studies on complex life machinery. However, current techniques targeting live cells and ...