Sepsis-induced organ failure is associated with high morbidity and mortality rates. The onset of an exaggerated host response to microbial invasion and/or trauma, is believed to be the primary cause of excessive inflammation and the subsequent tissue hypoperfusion observed in patients with severe sepsis. In our mouse model of sepsis induced by cecal ligation and perforation (CLP), symptoms indicative of the disease, including diarrhea, increased ventilation and persistent hypothermia, are present at six hours after the surgery (T6). In the untreated CLP mice, mortality occurs starting at T15. As induced hypothermia has shown to exert immunomodulatory effects, this study is aimed at assessing its potential in attenuating inflammation and improving survival in experimental sepsis. Our data has shown that deep hypothermia initiated at T6, by means of cold chamber-induced cooling, prolongs survival. Plasma cytokine quantification by enzyme-linked immunosorbent assays (ELISA) also reveals that induced deep hypothermia reduces tumour necrosis factor(TNF)-α and interleukin (IL)-6 production in untreated CLP mice. In contrast, induced moderate hypothermia does not have such effect. Antibiotic (cefotaxime) and saline resuscitation initiated immediately following CLP ensures survival. However, when these supportive treatments are initiated at T6, >50% mortality is observed in the CLP mice with or without induced hypothermia. In summary, this preliminary study provides proof for a downregulated inflammatory response mediated by external cooling. However, to achieve a survival benefit, treatment strategies in addition to cooling and antibiotics may be required.

Orientador: Francisco Hideo Aoki / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-26T19:53:42Z (GMT). No. of bitstreams: 1 Sauer_CarlosRobertodeOliveira_M.pdf: 4893312 bytes, checksum: 191dcebcc690c95e22eb505e300a4963 (MD5) Previous issue date: 2014 / Resumo: Introdução: Síndrome da resposta inflamatória sistêmica (SRIS) é uma situação clínica na qual ocorrem as alterações fisiológicas da sepse, mas que é desencadeada por uma agressão não infecciosa ao organismo. Foi definida em 1991, em consenso internacional, e, assim como a sepse, está associada à insuficiência de múltiplos órgãos e sistemas (IMOS) e à mortalidade. Não há muitos dados epidemiológicos a respeito da SRIS, mas sabe-se que a sepse grave e choque séptico são juntos a principal causa de morte nas unidades de terapia intensiva (UTIs) não coronarianas nos EUA e,no Brasil, são responsáveis por mais de 54.000 internações anualmente, com uma mortalidade associada de 32,9% e 64,1%, para sepse grave e choque séptico, respectivamente. Após documentar, em estudo fisiológico com cateter de artéria pulmonar, um caso de choque distributivo com depressão do miocárdio no pós-operatório imediato de uma cirurgia redutora de mama, sem qualquer associação a quadro infeccioso, foi feita, sem sucesso, uma extensa busca de casos semelhantes na literatura médica. Inclusive, nesta revisão, foi encontrada uma grande incidência de cirurgias estéticas de mama no Brasil: quase 280.000 por ano, dentre as quais 131.000 são mamoplastias redutoras. Objetivos: avaliar a prevalência de SRIS e SRIS grave no pós-operatório da cirurgia estética de mama e, secundariamente, avaliar os fatores de risco associados a sua ocorrência e discutir as possíveis implicações da SRIS nos cuidados peri-operatórios das cirurgias estéticas de mama. Casuística e método: foram realizados dois estudos epidemiológicos, um retrospectivo no Hospital Estadual de Sumaré¿UNICAMP (HES), a mesma instituição onde foi verificado esse caso de SRIS grave, envolvendo todas as pacientes que foram submetidas somente a mamoplastia redutora (de 2001 a 2012, com 154 pacientes) e outro estudo prospectivo no Hospital do Instituto do Coração de Campinas (Hospital ICC), onde também foram avaliadas pacientes submetidas à inserção e à troca de próteses mamárias, associadas ou não à lipoaspiração (primeiro semestre de 2012, com 24 pacientes). Resultados: no HES encontrou-se 17 casos de SRIS (11,0%) e três casos de SRIS grave (1,9%), sendo verificado, dentre estes, um caso de SRIS grave com choque. Não houve diferença entre os grupos de pacientes com e sem SRIS para 29 variáveis clínicas,-epidemiológicas e farmacológicas analisadas. Observou-se uma tendência a maior frequência de SRIS em pacientes submetidas a anestesia por halogenados, mas sem significância estatística (p>0,05). No estudo do Hospital ICC foi verificada uma prevalência de SRIS 29,2%. Nesse segundo estudo, além de se aproximar da realidade das cirurgias estéticas de nosso país, pois foi feito em um hospital particular não ligado a qualquer universidade, pudemos contar com o critério do leucograma, colhido após a cirurgia. Após exaustiva revisão da literatura médica, foram encontrados alguns possíveis fatores confundidores da análise, a saber:os anestésicos inalatórios (halogenados e óxido nitroso), o propofol, a anestesia peridural, o próprio tecido mamário (em sua anatomia e fisiologia apresenta interfaces com sistema imune) e o órgão adiposo (participa da constituição da mama e possui funções endócrinas, além de ser ontologicamente ligado ao sistema imune). Ao revisar o tipo de cirurgia realizado e a fisiopatogenia da SRIS, encontramos mais duas questões com relevância em termos saúde coletiva: a imunossupressão e a ativação da cascata de coagulação associadas à SRIS poderiam gerar uma população de mulheres mais suscetíveis às complicações infecciosas, à trombose venosa profunda (TVP) e ao trombo-embolismo pulmonar (TEP). Novamente, foram feitos novos levantamentos bibliográficos para abordar estas questões, sendo encontradas inúmeras referências associando o uso inadequado de antibióticos a complicações bacterianas (superinfecções) e artigos descrevendo, nesta situação específica de pós-operatório, o frequente descumprimento dos protocolos de profilaxia de TVP/TEP. Conclusão: na cirurgia estética de mama ocorre uma incidência de SRIS próximo a 30% (quando são utilizados os 4 critérios diagnósticos de SRIS) e uma incidência de SRIS grave de quase 2%. Também foi descrito um caso clínico de SRIS grave com choque no pós-operatório da cirurgia estética de mama, algo presente no dia a dia dos profissionais que atendem estas pacientes, mas sem prévio relato na literatura médica. Não foi encontrada qualquer associação entre SRIS e os fatores de risco analisados. É necessário estarmos atentos para uma melhor definição da importância deste quadro em termos de saúde pública, com um olhar protetor para a população de mulheres submetidas à cirurgia estética de mama, vulneráveis às complicações do pós-operatório numa frequência que pode ser maior que a esperada / Abstract: Introduction : SIRS is a clinical situation where the physiological changes due to sepsis occur, but triggered by a noninfectious aggression to the organism. It was defined in 1991, with international consensus, and like sepsis it is associated to multiple system organ failure (MSOF) and mortality. There is not much epidemiological data related to SIRS but it is known that severe sepsis and septic shock are together the leading cause of death in non-coronary ICUs in the U.S. and, In Brazil, they are responsible for more than 54,000 hospitalizations annually, with an associated mortality of 32.9% and 64.1% for severe sepsis and septic shock, respectively. After reporting, in a physiological study of pulmonary artery catheter, a case of septic shock with myocardial depression in the immediate postoperative of reductive mammoplasty, without any sign of infection, an extensive literature review was done without success, seeking similar cases in the medical literature. Moreover, in this review, a high frequency of cosmetic surgery in breast were found in Brazil: almost 280,000 per year, of which 131,000 were reductive mammoplasties. Objective: Assess the prevalence of SIRS and severe SIRS in the postoperative of cosmetic breast surgery and , secondarily , assess the risk factors associated to its occurrence and discuss the possible implications of SIRS in the perioperative care of cosmetic breast surgery. Patients and Methods: Two epidemiological studies were conducted, one was a retrospective epidemiological survey which took place at the Sumaré State Hospital ¿ UNICAMP, the same institution where this case was found, involving all patients who underwent reduction mammoplasty ( from 2001 to 2012, with 154 patients) and the other was a prospective study developed at the Campinas Heart Institute Hospital, where patients subjected to placement and replacement of breast implants, associated or not to liposuction were assessed (first semester of 2012, with 24 patients). Results At the Sumaré State Hospital 17 cases of SIRS were found (11.0%), and three cases of severe SIRS (1.9%), among which there was one case of severe SIRS with shock. There was no difference between the group of patients with and without SIRS, regarding the 29 clinical, epidemiological and pharmacological variables that were analyzed. A tendency for a higher frequency of SIRS in patients undergoing anesthesia by halogenated substances was observed, but without statistical significance (p>0.05).At the Campinas Heart Institute Hospital, the prevalence of SIRS was of 29.2%. In this second study, in addition to being similar to the reality of cosmetic surgeries of our country, because it was conducted in a private hospital not related to any university, we could rely on the leucocyte count, collected after surgery. After an exhaustive review of the medical literature, some possible confounding analysis factors were found, namely: inhalational anesthetics (nitrous oxide as the halogenated), propofol, epidural anesthesia, the breast tissue itself (in their anatomy physiology presents interfaces with the immune system) and the adipose organ (part of the constitution of the breast, it has endocrine functions and is ontologically linked to the immune system). When reviewing the type of surgery performed and the pathophysiology of sepsis, we found two other relevant issues: immunosuppression and activation of the coagulation cascade associated to SIRS could generate a population of women transiently more susceptible to infectious complications, Deep Vein Thrombosis (DVT) and Pulmonary Thromboembolism (PTE). Again, we reviewed the literature to address these issues, numerous references were found involving the inappropriate use of antibiotics for bacterial complications (superinfection) and articles describing the incorrect use of the protocols for prophylaxis of DVT / PTE. Conclusion: In cosmetic breast surgery there is an incidence of SIRS close to 30% ( when the four diagnostic criteria for SIRS are used) and an incidence of severe SIRS close to 2%. Moreover, a clinical case of SIRS was described in the postoperative of cosmetic breast surgery, which is present in the everyday routine of the professionals that work with these patients but has not previously been related in the medical literature. No association was found between SIRS and the analyzed risk factors / Mestrado / Clinica Medica / Mestre em Clinica Medica

Current Possibilities in Use of a Centrifugal Pump in the Cardiac Sugery Abstract Currently, the most commonly used technical solution for pumping blood during extracorporeal circulation during cardiac surgery, as well as for some types of ECMO (extracorporeal membrane oxygenation) are either a roller pump or centrifugal pump. Due to its advantages the centrifugal pump is mainly used for prolonged extracorporeal circulation in cardiac surgery and as a heart and / or lung support system. In current literature there is a lack of compelling scientific evidence that would clearly support its use in a routine cardiac surgery. The aim of our study was to compare both types of currently used blood pumps in longer cardiac procedures with deep hypothermic circulation arrest. In a randomized clinical study we had selected a group of patients that underwent a pulmonary endarterectomy (PEA) in order to demonstrate the positive effects of the centrifugal pump on the postoperative inflammatory reactions. There were no statistically significant differences between these two pumps when other clinical and laboratory parameters were observed. Based on the hypothesis that significant temperature changes during cardiac procedure with a deep hypothermia can affect sealing pressure of the endotracheal tube cuff, we performed a...

Current Possibilities in Use of a Centrifugal Pump in the Cardiac Sugery Abstract Currently, the most commonly used technical solution for pumping blood during extracorporeal circulation during cardiac surgery, as well as for some types of ECMO (extracorporeal membrane oxygenation) are either a roller pump or centrifugal pump. Due to its advantages the centrifugal pump is mainly used for prolonged extracorporeal circulation in cardiac surgery and as a heart and / or lung support system. In current literature there is a lack of compelling scientific evidence that would clearly support its use in a routine cardiac surgery. The aim of our study was to compare both types of currently used blood pumps in longer cardiac procedures with deep hypothermic circulation arrest. In a randomized clinical study we had selected a group of patients that underwent a pulmonary endarterectomy (PEA) in order to demonstrate the positive effects of the centrifugal pump on the postoperative inflammatory reactions. There were no statistically significant differences between these two pumps when other clinical and laboratory parameters were observed. Based on the hypothesis that significant temperature changes during cardiac procedure with a deep hypothermia can affect sealing pressure of the endotracheal tube cuff, we performed a...

Zymosan-induced peritonitis is a model commonly used to study systemic inflammatory response syndrome and multiple organ dysfunction syndrome. However, effects of zymosan on cardiac function have not been reported. We evaluated cardiac responses to zymosan in mice and the role of β-Glucan and dectin-1 in mediating these responses. Temperature and cardiac function were evaluated before and after intraperitoneal (i.p.) injection of zymosan (100 or 500 mg/kg) or saline. Chronotropic and dromotropic functions were measured using electrocardiograms (ECGs) collected from conscious mice. Cardiac inotropic function was determined by echocardiography. High-dose zymosan caused a rapid and maintained hypothermia along with visual signs of illness. Baseline heart rate (HR) was unaffected but HR variability (HRV) increased, and there was a modest slowing of ventricular conduction. High-dose zymosan also caused prominent decreases in cardiac contractility at 4 and 24 h. Because zymosan is known to cause gastrointestinal tract pathology, peritoneal wash and blood samples were evaluated for bacteria at 24 h after zymosan or saline injection. Translocation of bacterial occurred in all zymosan-treated mice (n=3), and two had bacteremia. Purified β-Glucan (50 and 125 mg/kg, i.p.) had no effect on temperature or ECG parameters. However, deletion of dectin-1 modified the ECG responses to high-dose zymosan; slowing of ventricular conduction and the increase in HRV were eliminated but a marked bradycardia appeared at 24 h after zymosan treatment. Zymosan-treated dectin-1 knockout mice also showed hypothermia and visual signs of illness. Fecal samples from dectin-1 knockout mice contained more bacteria than wild types, but zymosan caused less translocation of bacteria. Collectively, these findings demonstrate that zymosan-induced systemic inflammation causes cardiac dysfunction in mice. The data suggest that dectin-1-dependent and -independent mechanisms are involved. Although zymosan treatment causes translocation of bacteria, this effect does not have a major role in the overall systemic response to zymosan.

Background: Systemic inflammation can occur after transcatheter aortic valve replacement (TAVR) and correlates with adverse outcome. The impact of remote ischemic preconditioning (RIPC) on TAVR associated systemic inflammation is unknown and was focus of this study. Methods: We performed a prospective controlled trial at a single center and included 66 patients treated with remote ischemic preconditioning (RIPC) prior to TAVR, who were matched to a control group by propensity score. RIPC was applied to the upper extremity using a conventional tourniquet. Definition of systemic inflammation was based on leucocyte count, C-reactive protein (CRP), procalcitonin (PCT) and interleukin-6 (IL-6), assessed in the first 5 days following the TAVR procedure. Mortality was determined within 6 months after TAVR. RIPC group and matched control group showed comparable baseline characteristics. Results: Systemic inflammation occurred in 66% of all patients after TAVR. Overall, survival after 6 months was significantly reduced in patients with systemic inflammation. RIPC, in comparison to control, did not significantly alter the plasma levels of leucocyte count, CRP, PCT or IL-6 within the first 5 days after TAVR. Furthermore, inflammation associated survival after 6 months was not improved by RIPC. Of all peri-interventional variables assessed, only the amount of the applied contrast agent was connected to the occurrence of systemic inflammation. Conclusions: Systemic inflammation frequently occurs after TAVR and leads to increased mortality after 6 months. RIPC neither reduces the incidence of systemic inflammation nor improves inflammation associated patient survival within 6 months.

Objectifs : Définir les paramètres pharmacocinétiques du pantoprazole intraveineux en soins intensifs pédiatriques et déterminer l’influence qu’exercent sur ceux-ci les facteurs démographiques, le syndrome de réponse inflammatoire systémique (SRIS), la dysfonction hépatique et l’administration d’un inhibiteur du cytochrome (CYP) 2C19. Méthode : Cent cinquante-six concentrations plasmatiques de pantoprazole provenant d’une population de 20 patients (âgés de 10 jours à 16.4 ans) à risque ou atteints d’une hémorragie gastroduodénale de stress, ayant reçu des doses quotidiennes de pantoprazole de 19.9 à 140.6 mg/1.73m2, ont été analysées selon les méthodes non compartimentale et de modélisation non linéaire à effets mixtes. Résultats : Une clairance médiane (CL) de 0.14 L/h/kg, un volume apparent de distribution de 0.20 L/kg et une demi-vie d’élimination de 1.7 h ont été déterminés via l’approche non compartimentale. Le modèle populationnel à deux compartiments avec une infusion d’ordre zéro et une élimination d’ordre un représentait fidèlement la cinétique du pantoprazole. Le poids, le SRIS, la dysfonction hépatique et l’administration d’un inhibiteur du CYP2C19 constituaient les covariables significatives rendant compte de 75 % de la variabilité interindividuelle observée pour la CL. Seul le poids influençait significativement le volume central de distribution (Vc). Selon les estimations du modèle final, un enfant de cinq ans pesant 20 kg avait une CL de 5.28 L/h et un Vc de 2.22 L. La CL du pantoprazole augmentait selon l’âge et le poids tandis qu’elle diminuait respectivement de 62.3%, 65.8% et 50.5% en présence d’un SRIS, d’un inhibiteur du CYP2C19 ou d’une dysfonction hépatique. Conclusion : Ces résultats permettront de guider les cliniciens dans le choix d’une dose de charge et dans l’ajustement des posologies du pantoprazole en soins intensifs pédiatriques dépendamment de facteurs fréquemment rencontrés dans cette population. / Aims : To characterize the pharmacokinetics of intravenous pantoprazole in a paediatric intensive care population and to determine the influence of demographic factors, systemic inflammatory response syndrome (SIRS), hepatic dysfunction and concomitantly used cytochrome (CYP) 2C19 inhibitors on the drug’s pharmacokinetics. Methods : A total of 156 pantoprazole concentrations from 20 patients (aged from 10 days to 16.4 years) at risk for or with upper gastrointestinal bleeding, who received pantoprazole doses ranging from 19.9 to 140.6 mg/1.73m2/day, were analyzed using non compartmental and non linear mixed effects modelling (NONMEM) approaches. Results : The non compartmental results showed that median clearance (CL), apparent volume of distribution and elimination half-life were 0.14 L/h/kg, 0.20 L/kg and 1.7 h, respectively. The best structural model for pantoprazole was a two-compartment model with zero order infusion and first order elimination. Body weight, SIRS, age, hepatic dysfunction and presence of CYP2C19 inhibitors were the significant covariates affecting CL, accounting for 75% of interindividual variability. Only body weight significantly influenced central volume of distribution (Vc). In the final population model, the estimated CL and Vc were 5.28 L/h and 2.22 L, respectively, for a typical five year old child weighing 20 kg. Pantoprazole CL increased with weight and age whereas the presence of SIRS, CYP2C19 inhibitors and hepatic dysfunction, when present separately, significantly decreased pantoprazole CL by 62.3%, 65.8% and 50.5%, respectively. Conclusion : These results provide important information to physicians regarding selection of a starting dose and dosing regimen of pantoprazole for paediatric intensive care patients based on various factors frequently encountered in this population.

INTRODUÇÃO: Relatos conflitantes têm dificultado para se estabelecer o potencial benefício da glutamina (GLN) no tratamento de condições inflamatórias agudas. Nós avaliamos o efeito da infusão parenteral de GLN, prévia à pancreatite aguda (PA) experimental, nos mediadores inflamatórios, morbidade e mortalidade. MÉTODOS: Ratos Lewis (n = 131) receberam glutamina parenteral (grupo GG), solução salina (grupo SS ou controle), ou permaneceram sem infusão parenteral (grupo Sham) por 48h. Após este período, foi induzida PA por meio da injecção retrógrada de taurocolato de sódio no ducto pancreático. Sangue, amostras de pulmão, fígado, pâncreas e líquido ascítico foram colhidos a partir de 2, 12 e 24 horas após PA para avaliação das variáveis propostas (citocinas, hsp, histologia, amilase). Sessenta animais permaneceram vivos após PA para a análise da mortalidade em sete dias. RESULTADOS: A análise entre grupos não mostrou diferenças significativas nos níveis de citocinas (p > 0,05). Análise cinética dentro de cada grupo ao longo do tempo mostrou maior INF-y no grupo Sham e SS às 2h do que em 12h e 24h, maior IL-2 e inferior IL-10 no Sham, às 24h do que em 2h e 12h, e menor IL-10 no SS e GG em 24 h do que no tempo de 2h (p <= 0.05). O grupo GG exibiu maior expressão de HSP 90 no pulmão e no fígado do que no grupo Sham nos tempos de 2h e 12h, respectivamente; e maior expressão no fígado de HSP90 e HSP70 no grupo SS no tempo 12 horas (p < 0,01). O grupo Sham apresentou maior expressão de HSP 70 no pulmão e HSP 90 no fígado do que os outros grupos no tempo de 24h. Não ocorreram alterações na taxa de mortalidade. CONCLUSÕES: Em modelo de PA experimental induzida por taurocolato de sódio, o pré-tratamento com GLN parenteral melhorou o perfil dos mediadores inflamatórios, sem afetar a mortalidade / INTRODUCTION: Conflicting reports have hindered establish the potential glutamine (GLN) benefit in treating acute inflammatory conditions. We evaluated the effect of parenteral GLN infusion before experimental acute pancreatitis (AP), as systemic inflammation-reproducing model, on inflammatory mediators and mortality. METHODS: Lewis rats (n=131) received parenteral glutamine (GG group), saline (SS or Control group), or remained without parenteral infusion ( Sham group) for 48h. Thereafter, AP was induced by retrograde injection of sodium taurocholate into pancreatic duct. Blood, lung, liver and pancreas samples were collected from 2, 12 and 24h post-AP to assess serum cytokines levels, tissue HSP expression, histology and amylase. Sixty animals remained alive post-PA for seven-day mortality analysis. RESULTS: Punctual between-groups analysis did not show differences in cytokine levels (p > 0.05). Intragroup analysis over time showed higher INF-y in Sham and SS at 2h than at 12h and 24h, higher IL-2 and lower IL-10 in Sham at 24h than at 2h and 12h, and lower IL-10 in SS and GG at 24h than at 2h timepoint (p <= 0.05). GG group exhibited higher lung and liver HSP90 than Sham at 2h and 12h timepoints, respectively; and higher liver HSP90 and HSP70 than SS at 12h timepoint (p < 0.01). Sham group presented higher lung HSP70 and liver HSP90 than the others at 24h timepoint (p < 0.02). No changes occurred on mortality rate. CONCLUSIONS: In sodium taurocholate-induced PA model, pretreatment with parenteral GLN improved inflammatory mediator\'s profile, without affecting mortality

A isquemia do intestino delgado ocorre nas oclusões arteriais dos vasos mesentéricos ou associada à baixa perfusão tecidual causada por choque circulatório. Seus efeitos deletérios locais e sistêmicos frequentemente agravam a evolução clínica de muitas doenças. Este estudo experimental investiga como a reposição do volume intravascular utilizando duas soluções salinas com diferentes concentrações de sódio (solução salina fisiológica e solução 7,5% de cloreto de sódio) modifica a resposta inflamatória e o estresse oxidativo causados pela isquemia do intestino delgado. Ratos Wistar, machos, peso corporal entre 250 e 300 g, número total =102, foram submetidos à oclusão transitória da artéria mesentérica superior durante 45 minutos. No protocolo utilizado, os animais foram sorteados para inclusão em um de quatro grupos experimentais: isquemia falsa (IF), isquemia intestinal seguida da infusão de solução salina hipertônica 7.5% em volume de 4 ml/kg de peso (SH), isquemia intestinal seguida da infusão de solução salina 0.9% em volume de 33 ml/kg de peso (SF) e isquemia intestinal sem reposição do volume intravascular (ST). Quando apropriado, as soluções foram administradas lentamente (5 minutos) pela veia jugular externa imediatamente antes da reperfusão intestinal. Em cada grupo experimental, logo após a reperfusão intestinal, os animais foram sorteados para tempo de sobrevida: 2 horas, 4 horas ou 6 horas após a reperfusão. Amostras de sangue foram colhidas pela veia jugular externa em vários períodos: imediatamente após a liberação da oclusão da artéria mesentérica, 2 horas, 4 horas e 6 horas após a reperfusão intestinal. O plasma foi separado e foram realizadas as dosagens de interleucinas (IL-6 e IL-10). No tempo determinado, os animais foram submetidos à eutanásia em condições humanamente aceitáveis e, então, nesse momento, foram colhidas amostras de tecidos (intestino, fígado e pulmão) para posterior quantificação das concentrações de malondialdeído (MDA) e interleucinas (IL-6 e IL-10). A atividade da mieloperoxidase (MPO) também foi avaliada nessas amostras. Os animais que não receberam tratamento apresentaram uma taxa de mortalidade maior do que os demais grupos. Os grupos de animais tratados com reposição de volume intravascular apresentaram uma taxa de mortalidade semelhante ao grupo de isquemia falsa. Os animais que receberam reposição de volume intravascular com soluções cristalóides (SH ou SF) apresentaram concentrações de MDA, MPO, IL-6 e IL-10 nos tecidos (intestino, fígado e pulmão) comparáveis ao grupo de animais com isquemia falsa. Em todos os momentos, esses valores foram mais elevados no grupo que não recebeu tratamento. As concentrações plasmáticas da IL-6 e da IL-10 foram mais elevadas nos animais tratados com SH. As análises mostram que a simples abertura da cavidade abdominal causa um trauma cirúrgico relevante aos animais e é responsável pelas alterações observadas no grupo de isquemia falsa. Os resultados sugerem que a isquemia intestinal transitória (45 minutos) realizada por oclusão da artéria mesentérica superior em ratos representa um modelo experimental de moderada gravidade. Dessa maneira, o modelo é adequado aos estudos das alterações bioquímicas e celulares que ocorrem a curto, médio e longo tempo de sobrevida. Este estudo foi elaborado para análise dos fatores relativos ao estresse oxidativo e reação inflamatória que ocorrem nas primeiras horas que seguem a reperfusão intestinal. De uma maneira geral, os animais foram beneficiados pela reposição do volume intravascular com soluções cristalóides. A solução salina fisiológica foi utilizada em volume aproximadamente oito vezes superior à solução hipertônica 7,5% de cloreto de sódio. Comparativamente, a atenuação similar das respostas deletérias após a reperfusão intestinal atingida com o uso de menor volume da solução hipertônica 7,5% de cloreto de sódio representa um fator positivo para a mesma. Considera-se que a maior concentração plasmática das interleucinas (IL-6 e IL-10) encontrada nos animais tratados com solução hipertônica7,5% de cloreto de sódio esteja relacionada ao aumento de permeabilidade da microcirculação associado às soluções hipertônicas / Gut ischemia is responsible for both local and systemic deleterious events. Since reperfusion occurs in a previous ischemic superior mesenteric artery territory (SMA), a succession of harmful mechanisms begins in the luminal epithelium that quickly lengthens the limits of the intestinal tract. Depending on the extension of the intestinal system involved in the ischemic/reperfusion injury there will be severe repercussion to distant organs in response to SMA occlusion. Several diseases could be associated with variables degrees of intestinal ischemia. Even minor intensity of intestinal ischemia had deleterious systemic effects and often aggravates the clinical outcome of many diseases. Our study investigates how different forms of volume restoration could modify two important mechanisms of injury after intestinal ischemia: oxidative stress and inflammatory responses. Wistar rats (n=102) were submitted to transient superior mesenteric artery occlusion (SMAo). After randomization, animals were divided in four groups: Sham intestinal ischemia; infusion of small volume of 7.5% hypertonic saline (HS), or infusion of high volume of 0.9% saline (NS) just prior reperfusion, and animals that did not receive intra vascular volume treatment (NT). At sequential times, the animals were euthanatized and tissue samples (lung, liver, and intestine) were collected to Malondialdehyde (MDA) dosage and myeloperoxidase (MPO) activity. Also, sequential plasmatic concentration of IL-6 and IL-10 were done. Animals treated with both forms of volume infusion showed lower levels of tissue MDA, MPO, IL-6, and IL-10 than found in NT group. Plasmatic concentration of IL-6 and IL-10 were higher in animals treated with HS. Positive correlation was found between tissue concentration of IL-10 and IL-6. The mortality rate was similar between the treated rats and the group of sham ischemia. The mortality rate was higher in the non treated animals. In this rat model of transient intestinal ischemia, adequate maintenance of intravascular volemia decreases oxidative stress and synthesis of inflammatory markers. Small volume of 7.5% HS (4ml/Kg body weight) and high amounts of NS ( 33 ml/Kg body weight) had similar effects in attenuation of these responses. In this study, 7.5% HS attenuates deleterious effects found after intestinal ischemia with the main advantage of the smallest volume utilized when compared with NS solution. Plasmatic concentrations of IL-6 and IL-10 were higher in HS treated animals. This observation is supported by action of hypertonic/hyperosmotic solutions at the microcirculatory level. These solutions increase the local vascular permeability. This characteristic of 7.5% HS solution could facilitate the passage of the locally produced interleukin to the systemic circulation

Introdução: Sepse é uma síndrome complexa definida por resposta inflamatória sistêmica, de origem infecciosa e caracterizada por manifestações múltiplas que podem determinar disfunção ou falência de um ou mais órgãos ou sistemas. É a principal causa de morte em unidades de terapia intensiva em pacientes críticos e tem representado uma fonte constante de preocupação para os sistemas de saúde em todo o mundo, devido, principalmente, às taxas elevadas de morbimortalidade. O tratamento da sepse é um desafio e continua a ser uma tarefa difícil devido a inúmeros fatores interferentes. Um estudo do nosso grupo demonstrou que a Escherichia coli (E. coli) é capaz de se ligar CD16 de um modo independente de opsonina, levando a um aumento na resposta inflamatória e a inibição da sua própria fagocitose, por conseguinte, procurou-se identificar os peptídeos no proteoma da E. coli envolvidos neste cenário. Metodologia: Utilizando a metodologia de Phage Display, que consiste numa técnica de clonagem, que permite a expressão de diversas sequências de peptídeos na superfície de bacteriófagos, nós identificamos 2 peptídeos que obtiveram interação com CD16. Após a seleção dos peptídeos identificamos uma proteína de membrana de E.coli que possui alta similaridade com um de nossos peptídeos selecionados. Nós acreditamos que esta proteína de membrana possa estar envolvida no processo de evasão imune desenvolvida pela E.coli e parece ser um forte candidato como uma nova opção terapêutica para controlar infecções por E. coli. Conclusão: A identificação de proteínas capazes de induzir inibição de fagocitose, através do receptor CD16, pode ser usada como uma nova forma de tratamento da sepse, assim como explorada no tratamento de doenças autoimunes / Introduction: Sepsis is a complex syndrome defined by a systemic inflammatory response of infectious origin and characterized by multiple manifestations that can determine dysfunction/failure of one or more organs and systems. It is the leading cause of death in intensive care units and represents a major health problem around the world, mainly due to its high mortality and morbidity rates. The treatment of sepsis is challenging and remains a difficult task due to numerous interfering factors. A study from our group demonstrated that Escherichia coli (E. coli) is able to bind CD16 in an opsoninindependent manner, leading to an increase in the inflammatory response and inhibition of its own phagocytosis, therefore we sought to identify the peptides in the E. coli proteome involved in this scenario. Methods and Results: Using the Phage Display technique, which is a cloning technique that allows the expression of various peptide sequences on the surface of bacteriophages (phages) and selecting these on the basis of affinity for a target molecule, we identified two peptides that interact with CD16. Next, using bioinformatic tools, we found an E. coli membrane protein that has high similarity with one of our selected peptides. We believe this membrane protein is involved in the process of immune evasion developed by E. coli and it is a strong candidate as a new therapeutic option to control E. coli infections. Conclusion: The identification of proteins capable of inducing inhibition of phagocytosis through the CD16 receptor, can be used as a new treatment of sepsis, as well as exploited in the treatment of autoimmune diseases