Este trabalho foi financiado pelo National Institutes of Health EUA [concessão R01AI-39108 para ASB] ea American Heart Association [subsídios SDG 0630219N e AID 09GRNT2180065 para YQX].

1. Preparando o MRSA de Infecção <ol><li> Inocule uma ansa cheia de cultura MRSA de um tubo de estoque a -80 ° C a uma sangue de ovelha Trypticase Soy placa de agar (TSA) (ver Tabela de reagentes específicos e equipamentos), e incubar a 37 ° C durante a noite. </li><li> Verifique a pureza da cultura sobre a placa de ágar sangue (fenótipos semelhantes colônia) para ter certeza não há contaminação. </li><li> Escolha uma colónia da placa de sangue de ovelha TSA e inocular a colónia em 5 ml Trypticase Soy Broth (TSB) em um tubo de 15 ml snap-tapado. </li><li> Incubar a 37 ° C durante a noite com agitação a 200 rpm. </li></ol> 2. Preparando Cateteres Cirurgia Corte o tubo de polietileno (PI10,. Becton Dickinson, nenhuma ordem 427401) a 10 cm comprimento, e derreter uma extremidade pressionando a ponta com uma pinça estéreis. O objectivo da selagem uma extremidade do cateter é evitar hemorragia durante a cateterização. 3. Pré-sPreparação urgery e Anestesia <ol><li> Rato lugar Sprague-Dawley (Harlan, Indianapolis, Ind. fêmea, 250-300 gramas) em uma câmara contendo isofluorano em oxigénio da mistura de gases (50%: 50%) até que o anestésico tem efeito (por exemplo, os músculos estão relaxados e reflexos de pedais estão ausentes ), e manter os animais em um estado de anestesia durante a cirurgia com a mistura de gás. </li><li> Limpe a área do pescoço do queixo até um pouco abaixo do esterno com Betadine e etanol 70%. </li></ol> 4. Procedimento Cirúrgico <ol><li> Use uma técnica asséptica durante toda a cirurgia. Fazer uma incisão (1-1,5 cm) verticalmente através da pele só camada do pescoço acima do esterno. </li><li> Usando dissecção romba, separar a fáscia para expor a artéria carótida direita com 2 pares de pinças curvas dentadas. </li><li> Puxe delicadamente a artéria para fora da cavidade do pescoço, e coloque dois comprimentos de 10 cm de fio de seda sob a artéria e amarrar a artéria na extremidade exposta cefálica, coloque um clipe sobre a artery para evitar sangramento. </li><li> Fazer um pequeno furo no topo da artéria utilizando um introdutor de cateter (Becton Dickinson, ordem n. 406.999), inserir um cateter com um fórceps através do orifício na artéria, remover o grampo e empurrar para baixo do cateter para o coração até que a resistência seja cumprido. </li><li> Amarrá a sutura solto em torno da extremidade caudal da artéria e fixar o cateter no lugar com a sutura de seda quando o cateter está no lugar, tal como determinado por: i) o comprimento do cateter inserido (4-5 cm); resistência ii) um maior avanço e iii) pulsação do cateter com o batimento cardíaco. Deixar o cateter no lugar durante o resto da experiência. </li><li> Cortar sutura em excesso e as extremidades do cateter, e se certificar de que não há sangramento a partir do cateter. Dobre as pontas soltas sob a pele do pescoço e feche a pele com grampos de pele. </li><li> Coloque o rato na gaiola em um lugar morno até que recuperou da anestesia, e fornecer comida e água. Verifique o rato freqüentemente durante eapós a recuperação da anestesia. </li><li> Esta cirurgia é um &quot;Categoria E&quot; procedimento. Os procedimentos produzidos a dor é sem alívio com analgésicos desde infecções por MRSA que acompanham angústia para os animais. </li></ol> 5. Infecção por MRSA <ol><li> A infecção pode ser realizada entre 1 e 7 dias pós-cirurgia, mas manter consistente dentro experimentos. </li><li> Limpeza da cauda de rato com etanol a 70%, e injectar 0,5 ml MRSA com uma contagem de célula desejado (10 abril-10 junho ufc / animal para a maioria das cepas de S. aureus). Com 27 G agulha 1/2 polegada por via intravenosa a partir da veia da cauda Cuidado : cultura MRSA pertence ao nível de biossegurança 2 (BSL2) e tem potencial perigo moderado para o pessoal e do ambiente. </li><li> Manter a pressão no local até que a hemostase ocorre antes de retornar o rato para o compartimento. </li></ol> 6. Ratos sacrifício e tecidos-alvo Cultura <ol><li> Sacrificar ratos por injecção ip de pentobarbital de sódio (200 mg/ Kg) após 1 a 6 dias após a infecção. </li><li> Coloque o rato sobre as costas e limpe o peito com etanol 70%. </li><li> Fazer uma incisão em forma de V no peito abaixo esterno, e cortado a cartilagem de nervuras de cada lado do esterno para expor o coração. </li><li> Puxe o coração se suavemente, e clipe através do tecido do coração perto da aorta e dissecar até libertar o coração. </li><li> Coloque o coração em uma placa de Petri esterilizada com 4x4 polegadas dentro de gaze, faça um corte através da parede do ventrículo esquerdo interior e abrir a câmara do lado esquerdo. </li><li> Verifique visualmente para a colocação do cateter. Examinar e remover vegetações da válvula com uma tesoura e pinças. </li><li> Pesar e homogeneizar as vegetações, e fazer diluições seriadas com PBS para a cultura quantitativa. </li></ol> 7. Os resultados representativos Imediatamente após a inserção do cateter na artéria e empurrando para baixo a cerca de 4-5 cm do cateter para o coração, uma resistência será experienCED. Se nenhuma resistência é detectado, o cateter pode não ter sucesso, foi inserido no lado esquerdo da câmara do coração, que podem afectar a colocação do cateter. Um correcto posicionamento do cateter publicado anteriormente 9 é mostrada na Figura 1. Parte das amostras de infecção por MRSA precisam de ser cultivadas quantitativa a certificar-se a contagem viável exacta bacteriana para a infecção e pureza da amostra infecção. Além disso, os organismos recuperados a partir de vegetações deve ser os mesmos que os utilizados no inoculo. A Tabela 1 apresenta um exemplo de virulência de um S. aureus estirpe no modelo de rato endocardite, que foi publicado anteriormente 9. Todos os animais desafiados com inóculos de 10 5 e 10 6 ufc e sacrificados entre 3 a 6 dias após infecção endocardite desenvolveram com S. alta densidades aureus em vegetações cardíacas, bem como os rins e do baço ( <strong&gt; Tabela 1). Ratos com culturas de válvulas estéreis são considerados não infectados. <img alt="A Figura 1" src="/files/ftp_upload/3863/3863fig1.jpg" /> Figura 1. O cateter está em um lugar correto (lado esquerdo da câmara do coração), e vegetações diversas são visíveis em torno da válvula aórtica 9. <table border="1"><tbody><tr><td> Inóculo (n º de animas) </td><td colspan="3"> A média de log 10 CFU / g de tecido ± DP um em: </td></tr><tr><td></td><td> Vegetação </td><td> Rim </td><td> Baço </td></tr><tr><td> 10 6 UFC / animal (9) </td><td> 10,36 ± 0,85 </td><td> 7,30 ± 0,64 </td><td> 6,70 ± 0,57 </td></tr><tr><td> 10 5 UFC / animal (8) </td><td> 9,93 ± 0,53 </td><td> 7,14 ± 0,53 </td><td> 6,44 ± 0,63</td></tr><tr><td> 10 4 UFC / animal (7) </td><td> 3,46 ± 0,50 * </td><td> 1,81 ± 0,74 * </td><td> 1,58 ± 0,59 * </td></tr></tbody></table> um desvio, SD padrão. P &lt;0,001 em relação ao 10 5 ou 10 6 CFU-desafiados animais. Tabela 1. S. densidade aureus em vegetações cardíacas com diferentes inóculos na endocardite ratos 9.

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A endocardite rato é um modelo animal importante e bem caracterizado para estudos in vivo na patogénese e agentes antimicrobianos para o tratamento de infecções bacterianas 9-11. Além disso, o modelo de rato endocardite representa um composto de infecções agudas e sub-aguda, e imita homólogo humano e endocardite válvula humana nativa. Além disso, acompanhados por um cateter na habitação, que representa uma infecção clássica associada ao biofilme, um problema comum e difícil n...

<table border="1"><tbody><tr><td> Nome do reagente </td><td> Companhia </td><td> Número de catálogo </td><td> Comentários </td></tr><tr><td> Placa de ágar sangue, sangue de carneiro 5% em Trypticase Soy ágar (TSA) </td><td> Diagnóstico Hardy </td><td> A10BX </td><td></td></tr><tr><td> Trypticase Soy Broth (TSB) </td><td> Becton Dickinson </td><td> 211825 </td><td></td></tr><tr><td> Agitando incubadora </td><td> Labnet </td><td> I5311-DS </td><td></td></tr><tr><td> Tubagem de polietileno </td><td> Becton Dickinson </td><td> 427401 </td><td></td></tr><tr><td> Introdutor de cateter </td><td> Becton Dickinson </td><td> 6999 </td><td></td></tr><tr><td></td><td></td><td></td><td></td></tr><tr><td> Isofluorance </td><td> Western Medical Suppy, Inc </td><td> 2147 </td><td> Siga as informações de segurança e manuseio </td></tr><tr><td> Instrumentos Cirúrgicos </td><td> Belas Ferramentas e Instrumentos de Pesquisa de Ciências Biomédicas, Inc. </td><td></td><td> Encontre os instrumentos das duas empresas para as suas necessidades </td></tr></tbody></table>

experimental endocarditis model of methicillin resistant staphylococcus aureus (mrsa) in rat

Infecções endovasculares, incluindo endocardite, são fatais síndromes infecciosas 1-3. Staphylococcus aureus é a causa mais comum em todo o mundo dessas síndromes com morbidade e mortalidade inaceitavelmente elevada, mesmo com tratamentos adequados agente antimicrobiano 4-6. O aumento em infecções devidas a resistente à meticilina S. aureus (MRSA), as altas taxas de falhas vancomicina clínicas de tratamento e os problemas crescentes de linezolida e resistência à daptomicina tem tudo ainda mais complicada a gestão de pacientes com essas infecções, e levou a custos de saúde de elevada 7, 8. Além disso, deve salientar-se que os estudos mais recentes com os resultados do tratamento com antibióticos têm sido baseados em cenários clínicos e, portanto, pode muito bem ser influenciada por factores do hospedeiro variando de paciente para paciente. Portanto, um modelo animal de infecção relevante endovascular em que factores do hospedeiro são semelhantes a partir de animal para animal é maiscrucial para investigar patogénese microbiana, bem como a eficácia de novos agentes antimicrobianos. Endocardite em rato é um bem estabelecida modelo experimental animal que se aproxima endocardite humana nativa. Este modelo tem sido utilizado para examinar o papel de determinados factores de virulência de estafilococos e da eficácia dos regimes de tratamento com antibióticos para endocardite estafilocócica. Neste relatório, nós descrevemos o modelo de endocardite experimental devido à MRSA que poderia ser usado para investigar patogênese bacteriana e da resposta ao tratamento com antibióticos.

Watch this Scientific Journal Video about Experimental Endocarditis Model of Methicillin Resistant Staphylococcus aureus MRSA in Rat at JoVE.com

Experimental Endocarditis Model of Methicillin Resistant Staphylococcus aureus MRSA in Rat

Endocardite modelo experimental de ratos devido à meticilina-resistente<em&gt; S. aureus</em&gt;.

Modelo Experimental de Endocardite resistente à meticilina<em&gt; Staphylococcus aureus</em&gt; (MRSA) em Rato

Endovascular infections, including endocarditis, are life-threatening infectious syndromes1-3. Staphylococcus aureus is the most common world-wide cause ...

experimental-endocarditis-model-methicillin-resistant-staphylococcus

Universidad de Cartagena UDEC

Research

JoVE Journal

Immunology and Infection

Experimental Endocarditis Model of Methicillin Resistant Staphylococcus aureus (MRSA) in Rat

15.6K visualizações.  Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center. Endocardite modelo experimental de ratos devido à meticilina-resistente S. aureus.

Vídeo: Experimental Endocarditis Model of Methicillin Resistant Staphylococcus aureus MRSA in Rat

Acute Myocardial Infarction in Rats

With heart failure leading the cause of death in the USA (Hunt), biomedical research is fundamental to advance medical treatments for cardiovascular diseases. Animal models that mimic human cardiac disease, such as myocardial infarction (MI) and ischemia-reperfusion (IR) that induces heart failure as well as pressure-overload (transverse aortic constriction) that induces cardiac hypertrophy and heart failure (Goldman and Tarnavski), are useful models to study cardiovascular disease. In particular, myocardial ischemia (MI) is a leading cause for cardiovascular morbidity and mortality despite controlling certain risk factors such as arteriosclerosis and treatments via surgical intervention (Thygesen). Furthermore, an acute loss of the myocardium following myocardial ischemia (MI) results in increased loading conditions that induces ventricular remodeling of the infarcted border zone and the remote non-infarcted myocardium. Myocyte apoptosis, necrosis and the resultant increased hemodynamic load activate multiple biochemical intracellular signaling that initiates LV dilatation, hypertrophy, ventricular shape distortion, and collagen scar formation. This pathological remodeling and failure to normalize the increased wall stresses results in progressive dilatation, recruitment of the border zone myocardium into the scar, and eventually deterioration in myocardial contractile function (i.e. heart failure). The progression of LV dysfunction and heart failure in rats is similar to that observed in patients who sustain a large myocardial infarction, survive and subsequently develops heart failure (Goldman). The acute myocardial infarction (AMI) model in rats has been used to mimic human cardiovascular disease; specifically used to study cardiac signaling mechanisms associated with heart failure as well as to assess the contribution of therapeutic strategies for the treatment of heart failure. The method described in this report is the rat model of acute myocardial infarction (AMI). This model is also referred to as an acute ischemic cardiomyopathy or ischemia followed by reperfusion (IR); which is induced by an acute 30-minute period of ischemia by ligation of the left anterior descending artery (LAD) followed by reperfusion of the tissue by releasing the LAD ligation (Vasilyev and McConnell). This protocol will focus on assessment of the infarct size and the area-at-risk (AAR) by Evan's blue dye and triphenyl tetrazolium chloride (TTC) following 4-hours of reperfusion; additional comments toward the evaluation of cardiac function and remodeling by modifying the duration of reperfusion, is also presented. Overall, this AMI rat animal model is useful for studying the consequence of a myocardial infarction on cardiac pathophysiological and physiological function.

The rat model of acute myocardial infarction (AMI) is useful to study the consequence of a MI on cardiac pathophysiological and physiological function.

Infarto Agudo do Miocárdio em Ratos

With heart failure leading the cause of death in the USA (Hunt), biomedical research is fundamental to advance medical treatments for cardiovascular ...

Medicina

Subcutaneous Infection of Methicillin Resistant Staphylococcus Aureus (MRSA)

MRSA is a worldwide threat to public health, and MRSA skin and soft-tissue infections now account for more than half of all soft-tissue infections in the United States. Among soft-tissue infections, myositis, pyomyositis, and necrotizing fasciitis have been increasingly reported in association with MRSA arising from the community. To understand the interplay between MRSA and host immunity leading to more severe infection, the availability of animal models is critical, permitting the study of host and bacterial factors. Several infection models have been introduced to assess the pathogenesis of S. aureus during superficial skin infection. Here, we describe a subcutaneous infection model that examines the skin, subcutaneous, and muscle pathologies.

Subcutaneous Infection of Methicillin Resistant Staphylococcus Aureus MRSA

Murine skin and soft tissue infection model is utilized for assessing the virulence function of methicillin resistant Staphylococcus aureus (MRSA) and the host immunological responses. Here, we presented a subcutaneous infection model for skin and soft tissue infection.

Infecção subcutânea de Staphylococcus aureus resistente (MRSA)

MRSA is a worldwide threat to public health, and MRSA skin and soft-tissue infections now account for more than half of all soft-tissue infections in the ...

Imunologia e Infecção

A New Murine Model of Endovascular Aortic Aneurysm Repair

Endovascular aneurysm exclusion is a validated technique to prevent aneurysm rupture. Long-term results highlight technique limitations and new aspects of Abdominal aortic aneurysm (AAA) pathophysiology. There is no abdominal aortic aneurysm endograft exclusion model cheap and reproducible, which would allow deep investigations of AAA before and after treatment. We hereby describe how to induce, and then to exclude with a covered coronary stentgraft an abdominal aortic aneurysm in a rat. The well known elastase induced AAA model was first reported in 19901 in a rat, then described in mice2. Elastin degradation leads to dilation of the aorta with inflammatory infiltration of the abdominal wall and intra luminal thrombus, matching with human AAA. Endovascular exclusion with small covered stentgraft is then performed, excluding any interactions between circulating blood and the aneurysm thrombus. Appropriate exclusion and stentgraft patency is confirmed before euthanasia by an angiography thought the left carotid artery. Partial control of elastase diffusion makes aneurysm shape different for each animal. It is difficult to create an aneurysm, which will allow an appropriate length of aorta below the aneurysm for an easy stentgraft introduction, and with adequate proximal and distal neck to prevent endoleaks. Lots of failure can result to stentgraft introduction which sometimes lead to aorta tear with pain and troubles to stitch it, and endothelial damage with post op aorta thrombosis. Giving aspirin to rats before stentgraft implantation decreases failure rate without major hemorrhage. Clamping time activates neutrophils, endothelium and platelets, and may interfere with biological analysis.

Histological and biochemical modifications after aneurysm endograft exclusion are still unclear. We describe a new model of endograft implantation on a murine aneurysm. Through thrombus analysis with and without persistant circulating blood stream interface, and new endovascular biomaterials evaluation, this model will help to better understand endovascular aneurysm exclusion pathobiology.

Um novo modelo murino de reparação endovascular de aneurisma da aorta

Endovascular aneurysm exclusion is a validated technique to prevent aneurysm rupture. Long-term results highlight technique limitations and new aspects of ...

A Mouse Model to Assess Innate Immune Response to Staphylococcus aureus Infection

Staphylococcus aureus (S. aureus)&#160;infections, including methicillin resistant stains, are an enormous burden on the healthcare system. With incidence rates of S. aureus infection climbing annually, there is a demand for additional research in its&#160;pathogenicity. Animal models of infectious disease advance our understanding of the host-pathogen response and lead to the development of effective therapeutics. Neutrophils play a primary role in the innate immune response that controls S. aureus infections by forming an abscess to wall off the infection and facilitate bacterial clearance; the number of neutrophils that infiltrate an S. aureus skin infection often correlates with disease outcome. LysM-EGFP mice, which possess the enhanced green fluorescent protein (EGFP) inserted in the Lysozyme M (LysM) promoter region (expressed primarily by neutrophils), when used in conjunction with in vivo whole animal fluorescence imaging (FLI) provide&#160;a means of quantifying neutrophil emigration noninvasively and longitudinally into wounded skin. When combined with a bioluminescent S. aureus strain and sequential in vivo whole animal bioluminescent imaging (BLI), it is possible to longitudinally monitor both the neutrophil recruitment dynamics and in vivo bacterial burden at the site of infection in anesthetized mice from onset of infection to resolution or death. Mice are more resistant to a number of virulence factors produced by S. aureus that facilitate effective colonization and infection in humans. Immunodeficient mice provide a more sensitive animal model to examine persistent S. aureus infections and the ability of therapeutics to boost innate immune responses. Herein, we characterize responses in LysM-EGFP mice that have been bred to MyD88-deficient mice (LysM-EGFP&#215;MyD88-/- mice) along with wild-type LysM-EGFP mice to investigate S. aureus skin wound infection. Multispectral simultaneous detection enabled study of neutrophil recruitment dynamics by using in vivo FLI, bacterial burden by using in vivo BLI, and wound healing longitudinally and noninvasively over time.

A Mouse Model to Assess Innate Immune Response to Staphylococcus aureus Infection

An approach is described for real-time detection of the innate immune response to cutaneous wounding and Staphylococcus aureus infection of mice. By comparing LysM-EGFP mice (which possess fluorescent neutrophils) with a LysM-EGFP crossbred immunodeficient mouse strain, we advance our understanding of infection and the development of approaches to combat infection.

Um modelo do rato para avaliar a resposta imune inata à infecção de Staphylococcus aureus

Staphylococcus aureus (S. aureus)&#160;infections, including methicillin resistant stains, are an enormous burden on the healthcare system. With incidence ...

An Image Guided Transapical Mitral Valve Leaflet Puncture Model of Controlled Volume Overload from Mitral Regurgitation in the Rat

Mitral regurgitation (MR) is a widely prevalent heart valve lesion, which causes cardiac remodeling and leads to congestive heart failure. Though the risks of uncorrected MR and its poor prognosis are known, the longitudinal changes in cardiac function, structure and remodeling are incompletely understood. This knowledge gap has limited our understanding of the optimal timing for MR correction, and the benefit that early versus late MR correction may have on the left ventricle. To investigate the molecular mechanisms that underlie left ventricular remodeling in the setting of MR, animal models are necessary. Traditionally, the aorto-caval fistula model has been used to induce volume overload, which differs from clinically relevant lesions such as MR. MR represents a low-pressure volume overload hemodynamic stressor, which requires animal models that mimic this condition. Herein, we describe a rodent model of severe MR in which the anterior leaflet of the rat mitral valve is perforated with a 23G needle, in a beating heart, with echocardiographic image guidance. The severity of MR is assessed and confirmed with echocardiography, and the reproducibility of the model is reported.&#160;&#160;

A rodent model of left heart volume overload from mitral regurgitation is reported. Mitral regurgitation of controlled severity is induced by advancing a needle of defined dimensions into the anterior leaflet of the mitral valve, in a beating heart, with ultrasound guidance.&#160;

Um modelo de punção de folheto de válvula mitral transapical guiada por imagem de sobrecarga de volume controlada da regurgitação mitral no rato

Mitral regurgitation (MR) is a widely prevalent heart valve lesion, which causes cardiac remodeling and leads to congestive heart failure. Though the ...

Semi-Minimal Invasive Method to Induce Myocardial Infarction in Rats and the Assessment of Cardiac Function by an Isolated Working Heart System

Myocardial infarction (MI) remains the main contributor to morbidity and mortality worldwide. Therefore, research on this topic is mandatory. An easily and highly reproducible MI induction procedure is required to obtain further insight and better understanding of the underlying pathological changes. This procedure can also be used to evaluate the effects or potency of new and promising treatments (as drugs or interventions) in acute MI, subsequent remodeling and heart failure (HF). After intubation and pre-operative preparation of the animal, an anesthetic protocol with isoflurane was performed, and the surgical procedure was conducted&#160;quickly. Using a minimally invasive approach, the left anterior descending artery (LAD) was located and occluded by a ligature. The occlusion can be performed acutely for subsequent reperfusion (ischemia/reperfusion injury). Alternatively, the vessel can be ligated permanently to investigate the development of chronic MI, remodeling or HF. Despite common pitfalls, the drop-out rates are minimal. Various treatments such as remote ischemic conditioning can be examined for their cardioprotective potential pre-, peri- and post-operatively. The post-operative recovery was quick as the anesthesia was precisely controlled and the duration of the operation was short. Post-operative analgesia was administered for three days. The minimally invasive procedure reduces the risk of infection and inflammation. Furthermore, it facilitates rapid recovery. The &#8220;working heart&#8221; measurements were performed ex vivo and enabled precise control of preload, afterload and flow. This procedure requires specific equipment and training for adequate performance. This manuscript provides a detailed step-by-step introduction for conducting these measurements.

This article presents an efficient method to perform myocardial ischemia and subsequent chronic reperfusion in rats using a minimally invasive approach. In addition, left ventricular hemodynamic function of rats is assessed by echocardiography and isolated working heart methods.&#160;

Método invasivo semi-mínimo para induzir infarto do miocárdio em ratos e a avaliação da função cardíaca por um sistema cardíaco de trabalho isolado

Myocardial infarction (MI) remains the main contributor to morbidity and mortality worldwide. Therefore, research on this topic is mandatory. An easily ...

Implantation of Human-Sized Coronary Stents into Rat Abdominal Aorta Using a Trans-Femoral Access

Percutaneous coronary intervention (PCI), combined with the deployment of a coronary stent, represents the gold standard in interventional treatment of coronary artery disease. In-stent restenosis (ISR) is determined by an excessive proliferation of neointimal tissue within the stent and limits the long-term success of stents. A variety of animal models have been used to elucidate pathophysiological processes underlying in-stent restenosis (ISR), with the porcine coronary and the rabbit iliac artery models being the most frequently used. Murine models provide the advantages of high throughput, ease of handling and housing, reproducibility, and a broad availability of molecular markers. The apolipoprotein E deficient (apoE-/- ) mouse model has been widely used to study cardiovascular diseases. However, stents must be miniaturized to be implanted into mice, involving important changes of their mechanical and (potentially) biological properties. The use of apoE-/- rats can overcome these shortcomings as apoE-/- rats allow for the evaluation of human-sized coronary stents while at the same time providing an atherogenic phenotype. This makes them an excellent and reliable model to investigate ISR after stent implantation. Here, we describe, in detail, the implantation of commercially available human coronary stents into the abdominal aorta of rats with an apoE-/- background using a trans-femoral access.

This protocol describes the implantation of human coronary stents into the abdominal aorta of rats with an apoE-/- background using a trans-femoral access. Compared with other animal models, murine models carry the advantages of high throughput, reproducibility, ease of handling and housing, and a broad availability of molecular markers.

Implantação de stents coronários de tamanho humano na aorta abdominal de rato usando um acesso trans-femoral

Percutaneous coronary intervention (PCI), combined with the deployment of a coronary stent, represents the gold standard in interventional treatment of ...

A Reproducible Intensive Care Unit-Oriented Endotoxin Model in Rats

Sepsis and septic shock remain the leading cause of death in intensive care units. Despite significant improvements in sepsis management, mortality still ranges between 20 and 30%. Novel treatment approaches in order to reduce sepsis-related multiorgan failure and death are urgently needed. Robust animal models allow for one or multiple treatment approaches as well as for testing their effect on physiological and molecular parameters. In this article, a simple animal model is presented.
First, general anesthesia is induced in animals either with the use of volatile or by intraperitoneal anesthesia. After placement of an intravenous catheter (tail vein), tracheostomy, and insertion of an intraarterial catheter (tail artery), mechanical ventilation is started. Baseline values of mean arterial blood pressure, arterial blood oxygen saturation, and heart rate are recorded.
The injection of lipopolysaccharides (1 milligram/kilogram body weight) dissolved in phosphate-buffered saline induces a strong and reproducible inflammatory response via the toll-like receptor 4. Fluid corrections as well as the application of norepinephrine are performed based on well-established protocols.
The animal model presented in this article is easy to learn and strongly oriented towards clinical sepsis treatment in an intensive care unit with sedation, mechanical ventilation, continuous blood pressure monitoring, and repetitive blood sampling. Also, the model is reliable, allowing for reproducible data with a limited number of animals in accordance with the 3R (reduce, replace, refine) principles of animal research. While animal experiments in sepsis research cannot easily replaced, repetitive measurements allow for a reduction of animals and keeping septic animals anesthetized diminishes suffering.

Here, we present a reproducible intensive care unit-oriented endotoxin model in rats.

Um modelo de endotoxina de unidade de terapia intensiva reprodutível em ratos

Sepsis and septic shock remain the leading cause of death in intensive care units. Despite significant improvements in sepsis management, mortality still ...

<meta charset="utf8"></head><body>Modelos in vivo otimizados para estudos de infecção intracelular por S. aureus

Development and Assessment of Intracellular Infection Models for Staphylococcus aureus

S. aureus can invade and persist within host cells, including immune cells, which allows it to evade immune detection and clearance. This intracellular persistence contributes to chronic and recurrent infections, complicating treatment and prolonging the disease. Consequently, there is a critical need for an intracellular infection model to better understand, prevent, and treat infections caused by S. aureus. This study indicated that antibiotics effectively eliminated extracellular bacteria but could not eradicate those that had entered the cells. Thus, a stable intracellular infection in vitro was established by RAW264.7 infected with S. aureus and co-culturing them with antibiotics. Subsequently, an intracellular infection model in mice was established by injecting peritoneal macrophages containing the intracellular infection. Vancomycin effectively cleared bacterial loads in mice challenged with planktonic S. aureus; however, it was ineffective against mice infected with equal or lower levels of intracellular bacteria within the peritoneal macrophages. This indicates that the intracellular infection model of S. aureus was successfully established, offering potential insights for the prevention and treatment of intracellular infections.

<meta charset="utf8"></head><body>Desenvolvimento e Avaliação de Modelos de Infecção Intracelular para Staphylococcus aureus

Staphylococcus aureus (S. aureus) has the capability to disseminate throughout the body, causing persistent and recurrent infections. To better understand these processes, this study establishes an intracellular infection model for S. aureus. This model will provide a crucial foundation for investigating the mechanisms behind intracellular infections.

Desenvolvimento e Avaliação de Modelos de Infecção Intracelular para Staphylococcus aureus

S. aureus can invade and persist within host cells, including immune cells, which allows it to evade immune detection and clearance. This intracellular ...

Modelo Experimental de Endocardite resistente à meticilina

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