Orientadores: José Dirceu Ribeiro, Carlos Emílio Levy / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-26T05:15:22Z (GMT). No. of bitstreams: 1 Ferreira_AdrianaCarolinaMarques_M.pdf: 1197514 bytes, checksum: 10b9c6c66730ad6487f8cc77ed1cde9c (MD5) Previous issue date: 2014 / Resumo: Introdução: A eficiente detecção de microrganismos nas vias aeríferas de pacientes com fibrose cística (FC) possibilita antibioticoterapia dirigida, melhor manejo ambulatorial e promove maior preservação da função pulmonar. Métodos para melhorar a identificação bacteriana estão em estudo, porém, não fica claro na literatura o papel da solução salina hipertônica (SSH) no auxílio da detecção desses microrganismos. Objetivo: Verificar a eficácia da SSH a 7% na identificação de microorganismos nas secreções das vias aeríferas em pacientes com FC e comparar com variáveis clinicas e laboratoriais. Método: Incluídos 64 pacientes com FC, com coleta de escarro ou swab de secreção de orofaringe pré e após inalação com SSH-7%. A identificação bacteriana foi realizada pelas técnicas de rotina no laboratório de Microbiologia. Resultados: Dos pacientes, 34(53,1%) eram do sexo feminino, com idade média de 12,11(±5,12). Do total de culturas microbiológicas realizadas (704 antes e após a SSH-7%), não houve diferença estatisticamente significante entre os resultados positivos, sendo 101 antes e 118 depois (OR=0,8319, IC=0,622-1,111). O mesmo foi observado para o número de espécies identificadas, sendo inicialmente identificados 7 microrganismos diferentes, e após a SSH-7% 11(p=0,1895), contudo houve aumento na identificação de 4(36,36%) espécies diferentes. Na análise semi-quantitativa e tipo de material (escarro ou swab) não houve diferença (p>0,05). No total foram obtidos após a SSH-7%, 25 resultados positivos que eram negativos e o contrário ocorreu para 9 pacientes. Não houve efeitos colaterais devido a SSH-7%.Conclusão: Apesar de não ocorrer diferença estatisticamente significativa, pode-se observar maior número de resultados positivos,detecção de maior número de patógenos e de espécies diferentes de microrganismos e aumento de amostras de escarro no lugar do swab após o uso da SSH-7% / Abstract: Introduction: The efficient detection of microorganisms in airways of cystic fibrosis (CF) patients allows targeted antibiotic therapy, better outpatient care and, consecutively, lung function preservation. Methods to improve bacteria identification have been studied. The role of hypertonic saline solution (HSS) in sputum collection, for bacteria identification, is not clear yet. Aim: Verify the effectiveness of HSS in the identification of microorganisms in airway secretions in patients and compare with clinical and laboratory variables. Methods: The study enrolled 64 CF patients, with a sputum sample or swab before and after inhalation with HSS 7%. Bacterial identification was performed by routine laboratory techniques in microbiology. Results: Of the 64 patients, female: 34 (53.1%); mean age: 12.11 (±5.12) years. Of the total microbiological analysis performed (704 before and after of 7% HSS), there was no difference between positive results between the positive results, being, 101 before and 118 after (OR= 0.832, CI= 0.622-1.111). The same was observed for the number of microorganisms species, being initially identified 7 species and after, 11 species (p= 0.1895), an increase of four different species (36.36%). In semi-quantitative analysis, there was no difference (p> 0.05). After of 7% HSS, 25 new positive results were observed and the opposite occurred in nine patients. No collateral effects were observed due to 7% HSS. Conclusion: Although statistically significant difference does not occur, the 7% HSS allowed a greater number of microbiological identification in sputum from airways, as in absolute number and as different microorganisms¿ species / Mestrado / Saude da Criança e do Adolescente / Mestra em Ciências

Abstract During surgery of the aortic arch and pediatric heart surgery, the blood flow to the brain has to be interrupted at times to allow a bloodless operation field and adequate conditions for surgical repair. During this no-flow period the brain is exposed to a high risk of ischaemic injury, as it will become irreversibly damaged after 5 minutes of circulatory arrest at 37°C. Additional time can be gained by cooling the patient with an extracorporeal heart-lung machine, as hypothermia reduces the cerebral metabolic rate and allows longer safe periods of circulatory standstill. This method of cerebral protection, called hypothermic circulatory arrest (HCA), is widely used in clinical practice. Thus the brain becomes susceptible to ischaemic injury after 30 minutes of HCA at 15°C. Lower temperatures than this are not practicable, however, as they require longer periods of cardiopulmonary bypass, which may further aggravate cerebral injury. To ensure a better outcome for patients undergoing these operations, additional ways of protecting the brain are required. The present work focuses on neuroprotective biochemical and fluid therapy methods for use during HCA, employing a surviving porcine model. Fructose-1,6-bisphosphate (FDP), a high-energy intermediate of glycolysis, was examined for potential neuroprotective properties in two cerebral injury settings associated with HCA. First, FDP was administered before and after a 75-minute period of HCA at a brain temperature of 18°C. This led to better survival, neurological recovery and brain histopathological findings and had supportive effects on brain metabolism (I). Second, a 25-minute period of HCA along with an iatrogenic embolic load produced by microsphere injection was used to generate a massive ischaemic injury to the brain. In this setting FDP did not affect the neurological outcome but had a clear supportive impact on cerebral metabolism (II). In addition, cerebral histopathological samples taken during the first study were analysed by electron microscopy, which revealed significant preservation of the ultrastructure in the FDP-treated animals (III). Hypertonic saline dextran (HSD) is a novel fluid therapy method which has been shown to enhance the outcome after hypovolaemic shock with or without head injury and is potentially very effective in reducing ischaemia-reperfusion injury. Its administration led to a decrease in intracranial pressure, improved brain metabolism, faster and better recovery and less histopathologically observable morphological damage (IV). The findings indicate that both FDP and HSD have significant neuroprotective properties and should be assessed in humans as well.

Adenosine 5’ triphosphate (ATP) is a molecule central to life for its role as the cellular energy currency, and a purine nucleotide which serves as a building block of RNA. Thus, on the backdrop of an indispensible intracellular role of ATP, its identification as an extracellular signaling molecule in early 1970s came as a surprise. A novel doctrine, termed as ‘purinergic signaling’, was thus put forth. By definition, purinergic signaling consists of the signaling events triggered by binding of extracellular ATP- a purine nucleotide, and its breakdown products (viz., ADP, AMP, and adenosine) to their cognate receptors, which in turn are termed as ‘purinergic receptors’. Based on their ligand affinity, purinergic receptors are classified into two groups- P1 and P2 receptors. P2 receptors are further subclassified as P2X and P2Y receptors. Till date, four P1 receptors (viz. A1, A2a, A2b, and A3), seven P2X receptors (P2X1-7), and eight P2Y receptors (P2Y1, P2Y2, P2Y4, P2Y6, P2Y11, P2Y12, P2Y13, and P2Y14) have been cloned and characterized. Conceptually, the first step of purinergic signaling is the release of ATP from an intact cell on encountering a stimulant or a modulator. The main mechanisms of such cellular ATP release include vesicular exocytosis and the release through conductive channels. ATP thus released, binds to its cognate receptors (i.e. P2X receptors, and certain P2Y receptors) and triggers the ‘purinergic signaling’ pathway that modulates the cellular response. In addition to purinergic receptors, cells also express ATP degrading enzymes on their surface, which break ATP down into ADP, AMP, and adenosine. ADP and adenosine, in turn, bind to their cognate receptors (certain P2Y receptors, and P1 receptors respectively) and further contribute to shaping the cellular response to a given cue. Thus, purinergic signaling is a highly dynamic process with pleiotropic downstream effects. First demonstrated in the context of neurotransmission, the phenomenon of purinergic signaling is now widely recognized and has been shown to play a role in regulating functional responses of cells of diverse origins, immune cells being one of them. Purinergic signaling in lymphocytes- an important subset of immune cells- is a common thread for the present research exercise, wherein we have addressed two sets of questions, one of academic curiosity and the other of clinical interest. In the former and the major part, we have examined whether purinergic signaling plays a role in functional aspects of ‘gamma delta (γδ) T cells’, which represent a unique subset of lymphocytes. Whereas, the latter part elaborates on the already identified involvement of purinergic signaling in T cell stimulatory action of ‘hypertonic saline (HS)’, which is used to treat trauma patients. The thesis, thus, is divided into five parts- the ‘Introduction’, ‘Aims and Scope of the study’, ‘Chapter 1’, ‘Chapter 2’, and ‘Summary of the work’. Understanding the questions posed in the present context, strategy designed to answer them, and eventually the experimental results answering these questions invoke basic knowledge of purinergic signaling, which has been attempted to be conferred through the ‘Introduction’ section. The discovery of purinergic signaling, its central theme, and individual molecular players involved in this signaling pathway are highlighted here. From the viewpoint of the present research endeavor, salient findings from the current literatureabout the involvement of purinergic signaling in the functional activities of various subsets of immune cells- are reviewed towards the end of this section. The ‘Introduction’ is followed by definition of the objectives for the present exercise, which are enlisted under ‘Aims and scope of the study’. Here, a brief overview of the background data that led us towards these objectives precedes the actual list of questions which we have approached. Purinergic signaling has been shown to play a role in the activation of ‘conventional αβ T’ cells. So we asked whether a similar purinergic signaling pathway also operates in unconventional γδ T cells. Thus, ‘Chapter 1’ is dedicated to answering the first set of questions about the role of purinergic signaling in γδ T cell activation. The chapter starts off by introducing γδ T cells. The topics such as discovery of γδ T cells, ontology, development, diversity, and distribution of these cells, and most importantly- their antigenic specificity and response are reviewed herein. The details of the experimental procedures employed to answer the defined objectives follow this introduction. We have carried out our experiments on γδ T cells in human circulation. For in vitro stimulation, we have used anti-CD3 + anti-CD28-coated beads (beads) or isopentenyl pyrophosphate (IPP), a γδ T cell specific stimulant. We observed that, circulating human γδ T cells rapidly release ATP on stimulation with beads or IPP. Pannexin-1 and connexin hemichannels, as well as vesicular exocytosis contribute to the ATP release. Real time RT-PCR data revealed that γδ T cells predominantly express purinergic receptors A2a, P2X1, P2X4, P2X7, and P2Y11. Of these, the inhibition of P2X4 receptors downregulated cytokine expression by γδ T cells post- in vitro stimulation, and also inhibited cytotoxic activity of γδ T cells towards Daudi cells. Selective translocation of P2X4 receptors to the immunological synapse was seen to be the underlying mechanism for these effects. Collectively, these data suggested that autocrine/paracrine purinergic signaling through P2X4 receptors indeed plays an important role in the functional aspects of circulating human γδ T cells. The experimental results are compiled in ‘Chapter 1’; which concludes with the ‘Discussion’ on the mentioned findings, and possible in vivo applications. ‘Chapter 2’ deals with the role of purinergic signaling in HS resuscitation. In addition to restoring the hemodynamic parameters, fluid replacement with small volumes of concentrated NaCl solution (HS) has been reported to reverse the suppression of T cells commonly found in the trauma subjects. Through an in vitro study using Jurkat cells as a model for primary human T cells, it has been shown earlier that, on HS exposure T cells release ATP- which binds to P2X7 receptors and promotes calcium influx. HS treatment also elicits phosphorylation of p38; and put together, Ca2+ influx and phosphorylated p38 synergize with TCR-induced stimulation resulting in the enhancement of transcriptional upregulation of IL-2. However, the mechanism of release of ATP on HS treatment and the possible involvement of P2X1 and P2X4 receptors expressed by T cells had not been addressed in this study. These very questions thus formed the objectives of the second part of present work. Experiments aimed to answer these questions showed that on HS treatment, Jurkat cells release ATP through pannexin-1 hemichannels. The released ATP binds to purinergic receptors P2X1, P2X4, and P2X7. This in turn triggers the downstream signaling cascade leading to phosphorylation of p38 and upregulation of IL-2 transcription, hence augmenting the T cell function. An overview of HS resuscitation, experimental protocols and results, and the discussion on the pathophysiological relevance of these findings comprise ‘Chapter 2’. Hence, we have found the answers to the questions we began with. The results are listed in a point-wise manner under the ‘Summary of the work’. Taken together, our data shows that: (i) Purinergic signaling does play a role in the functional aspects of circulating human γδ T cells. The release of ATP by γδ T cells post-stimulation, and autocrine/paracrine signaling through P2X4 receptors are the main components in this context. (ii) ATP release through pannexin-1 hemichannels, and autocrine/paracrine signaling through P2X1, P2X4, and P2X7 receptors underlie the mechanism of action of HS.

Objective: Establish and validate an experimental pain model that will create pain for at least 20-minutes and then use the model to determine if: 1) cryotherapy decreases experimentally induced pain, 2) experimentally induced pain contributes to arthrogenic muscle inhibition, and 3) cold application influences pain or arthrogenic muscle inhibition. To answer these questions we conducted two experiments, the results of which are presented in two manuscripts. Methods: Seventy (n = 30 for experiment I and n = 40 for experiment II), physically active healthy male subjects participated. Interventions: Independent variables used for experiment I were condition (5% hypertonic saline infusion/cryotherapy, no-saline infusion/cryotherapy, 5% hypertonic saline infusion/sham) and time (precondition, every minute during a condition, and 10 minutes following each condition). For experiment II, independent variables were treatment (saline infusion, saline infusion/cryotherapy, saline infusion/sham, and no-saline infusion) and time (pretreatment, posttreatment, and 30-minutes posttreatment). Dependent variables measured were pain perception, knee surface and ambient temperatures, and Hmax, and Mmax measures (experiment II only). Results: Saline caused more pain than no-saline at minutes 3, 4, and 5 during infusion. Pain caused by saline and sham application remained constant from 4 minutes during application through 1 minute following application. Cold application decreased pain for 16 minutes. Pain resulted in arthrogenic muscle inhibition following and 30 minutes following saline infusion. Cryotherapy removed inhibition following but not 30 minutes following application. Pain for the saline groups increased following infusion as measured with the pain rating index and visual analogue scale. According to pain rating index, cryotherapy did not decrease pain; however, cryotherapy decreased pain as measured with the visual analogue scales. No change in temperature occurred during the non-cooling conditions. Ambient temperatures fluctuated less than 1°C. Conclusion: Saline infusion caused anterior knee pain for over 20 minutes and resulted in arthrogenic muscle inhibition. Cryotherapy disinhibited the quadriceps motoneuron pool and reduced pain as measured with visual analogue scales. Cryotherapy did not decrease pain as measured with the McGill pain questionnaire.

Context: Knee pain is experienced by many people. Because of this, authors have started researching the effects of pain on lower extremity mechanics and also on static and dynamic postural control. However, the effects of pain are difficult to study due to associated confounding variables. Objective: We asked: (1) Will experimentally-induced anterior knee pain alter perceived pain using the visual analogue scale? ; (2) will perceived pain affect postural control as measured by center-of-pressure during static and dynamic movement? Design: Crossover. Setting: Biomechanics laboratory. Participants: Fifteen healthy subjects. Intervention: Each subject participated in single leg quiet stance, landing, and walking trials under three conditions (pain, sham, control), at three different times for each condition (pre-injection, injection, and post-injection). Main Outcome Measures: The dependent variables were measured at pre-injection, injection, and post-injection. Pain was measured using the visual analogue scale across all three times during each condition. Center-of-pressure sway was measured during single leg quiet stance to calculate the average center-of-pressure velocity in the anterior-posterior and medial-lateral directions. The center-of-pressure time to stabilization was measured in anterior-posterior, medial-lateral, and vertical directions, and center-of-pressure trajectory excursion was measured in the medial-lateral direction during walking. Results: Perceived pain was significant (P < 0.05) but did not affect postural control as measured by center-of-pressure medial-lateral and anterior-posterior sway during single leg quiet stance, in time to stabilization during landing, and in medial-lateral excursion during walking. Conclusions: Injection of hypertonic saline resulted in statistically significant perceived pain but did not affect postural control as measured by center-of-pressure medial-lateral and anterior-posterior sway during single leg quiet stance, in time to stabilization during landing, and medial-lateral excursion during walking.

No description available.

Diss. Linköping : Univ., 2003.

Sepse é a resposta inflamatória sistêmica do hospedeiro à infecção, que pode ser desencadeada por bactérias, vírus ou fungos. Há aumento da produção de mediadores inflamatórios como citocinas, quimiocinas espécies reativas de oxigênio e do recrutamento de neutrófilos. A administração de solução salina hipertônica 7,5% (SH) acarreta na modulação da resposta inflamatória e hemodinâmica culminando na redução da morbidade e mortalidade em modelos de pancreatite e choque hemorrágico. No presente trabalho, estudamos os efeitos da SH na sepse, induzida por ligadura e perfuração cecal (CLP) em camundongos Balb/C, divididos em 3 grupos: CLP sem nenhum tratamento (CLP); CLP tratado com solução salina isotônica 0,9% (SS) e CLP tratado com SH 7,5% (SH); um quarto grupo foi utilizado como controle, no qual não foi induzido sepse ou administrado tratamento (C); ambos os tratamentos foram aplicados 30 min. após CLP. Lavado peritoneal, intestino e pulmão foram coletados após 6h, 12h e 24h para a análise de citocinas (TNF-, IL-6 e IL-10), produção de oxido nítrico, peroxidação lipídica, infiltração de neutrófilos, moléculas de adesão (ICAM-1 e VCAM-1) e quimiocinas (CXCL-1). O grupo SH mostrou aumento de sobrevida (60%) em comparação aos grupos SS (46,6%) e CLP (33,3%) após 168h. SS apresentou aumento na produção de TNF- (27,3 ± 3,05 pg/ml) em 12h comparado ao grupo CLP (14,07 ± 1,68 pg/ml) e SH (19,66±3,19pg/ml); O efeito da SH na concentração de TNF permanece até 24h (6,2 ± 3,5 pg/ml vs. CLP 73,40± 49,52 pg/ml); a produção de IL-10 em 24h aumentaram nos grupos CLP (CLP - 3,12 ± 0,46 pg/ml) e SS (2,9 ± 0,9 pg/ml) em relação ao grupo SH (0,59 ± 0,34 pg/ml). Em 24h a produção de nitrito mostrou-se reduzida no grupo SH (6,77 ± 0,82 pg/ml) comparado com SS (10,65 ± 1,08 pg/ml), no pulmão. No intestino, a produção de nitrito, em 6h, diminuiu no grupo SH (1,27 ± 0,19 pg/ml) comparado com CLP (2,44 + 0,51 pg/ml). No grupo SH houve redução do infiltrado de neutrófilos no pulmão em 24h, através da redução de moléculas de adesão e concentração de mieloperoxidase, em comparação com CLP (29,4 + 5,7 ng/mg ; 3,02 + 0,41 mU/mg). Nossos resultados indicam que SH modula a resposta inflamatória, além de melhorar a sobrevida de animais submetidos à sepse experimental / Sepsis is a systemic inflammatory response to infection triggered by bacteria, virus and fungi. There is a rise in inflammatory mediators as citokynes, chemokynes, reactive oxygen species and neutrophil recruitment (1). The hypertonic saline solution (SH) has been showed to improve hemodynamic and inflammatory response. We studied the hypertonic solution effects in sepsis through cecal ligation and puncture (CLP) in mice Balb-C, divided in 3 groups: CLP without treatment (CLP); CLP treated with isotonic saline solution 0,9% - 34mg/Kg (SS); CLP treated with hypertonic saline solution 7,5% - 4ml/Kg (SH); and a 4th group indicating the basal values without both CLP and treatment (C); both treatments were administrated 30 min after CLP. The lung, gut and peritoneal fluid were collected after 6h, 12h and 24h to analyze cytokines levels, oxide nitric, lipid peroxidation and neutrophil infiltration. The SH group showed higher survival rats (60%) when compared to SS (46,6%) and CLP (33,3%) after 168h (7 days). TNF- level in the SS group (27,3 ± 3,05 pg/ml) was increased at 12h when compared to CLP (14,07 ± 1,68 pg/ml) and SH (19,66±3,19pg/ml); and at 24h the SH (6,2 ± 3,5 pg/ml) decreased its level when compared to CLP (73,40± 49,52 pg/ml); IL-10 level at 24h was increased in CLP (CLP - 3,12 ± 0,46 pg/ml) and SS (2,9 ± 0,9 pg/ml) in relation to SH (0,59 ± 0,34 pg/ml). In 24h, the quantification of nitrite decreased in SH (6,77 ± 0,82 pg/ml) compared with SS (10,65 ± 1,08 pg/ml) in lung. In intestine, nitrite levels diminished in SH (1,27 ± 0,19 pg/ml) in relation to CLP (2,44 + 0,51 pg/ml) in 6h. SH group reduced the neutrophil infiltration in lung, through adhesion molecule and myeloperoxidase at 24h (ng/mg;1,49 + 0,24 mU/mg) in relation to CLP(29,4 + 5,7 ng/mg ; 3,02 + 0,41 mU/mg). Our results suggest that the volume replacement of both treatments modulate pro and anti-inflammatory mediators of an inflammatory response to infection, but hypertonic solution presented a more effective effect

INTRODUÇÃO: Estudos recentes em modelos experimentais de sepse demonstraram as propriedades antioxidante e anti-inflamatória do etilpiruvato. Diferentes modelos experimentais também demonstraram que pequenos volumes de solução salina hipertônica (7,5%) melhoram a hemodinâmica, a microcirculação e modulam o sistema imunológico. Este estudo teve como objetivo investigar os efeitos do etil-piruvato, da solução salina hipertônica e da solução de Ringer lactato sobre a microcirculação mesentérica em modelo de sepse induzida por Escherichia coli viva em ratos. MÉTODOS: Ratos Wistar machos receberam por via endovenosa uma suspensão de E. coli ou foram submetidos ao procedimento cirúrgico do grupo falso-operado. Após três horas da infusão bacteriana os animais foram randomizados em: grupo controle não tratado, grupo tratado com solução de Ringer lactato (4mL/kg i.v.); grupo tratado com solução de Ringer lactato (4 mL/kg i.v.) associado a etil-piruvato (50mg/kg) e grupo tratado com solução salina hipertônica (7,5%, 4 mL/kg i.v.). Após 24 horas da bacteremia, as interações leucócito-endotélio foram investigadas por microscopia intravital, e a expressão de P-selectina e da molécula de adesão intercelular (ICAM)-1 determinada por imuno-histoquímica. Leucograma e contagem de plaquetas foram realizadas no início do estudo, 3 horas e 24 horas após a inoculação de E. coli. RESULTADOS: Os grupos não tratado e tratado com solução de Ringer lactato exibiram um aumento no número de leucócitos rollers (~ 2,5 vezes), leucócitos aderidos (~ 3,0 vezes), e de leucócitos migrados (~ 3,5 vezes) comparados ao grupo falso operado. O tratamento com etil-piruvato reduziu o número de leucócitos rollers, aderidos e migrados aos níveis obtidos no grupo falso operado (p > 0,05). Efeitos semelhantes foram observados nos animais tratados com a solução salina hipertônica (p > 0,05). A expressão de P-selectina e de ICAM-1 aumentou significativamente na microcirculação mesentérica no grupo não tratado, comparado ao grupo falso operado (p < 0,001). Todos os tratamentos reduziram a expressão de ambas moléculas de adesão, sendo os grupos tratados com etil-piruvato e solução salina hipertônica mais eficazes. A infusão de bactérias provocou leucopenia significante, seguida por leucocitose com granulocitose, e concomitante redução progressiva no número de plaquetas. CONCLUSÕES: Os dados apresentados sugerem que o etil-piruvato e a solução salina hipertônica (7,5%) eficientemente reduziram a resposta inflamatória na microcirculação mesentérica no presente modelo experimental de sepse induzida por E. coli viva; associada, pelo menos em parte, a menor expressão de moléculas de P-selectina e ICAM-1 / BACKGROUND: Experimental studies on sepsis have demonstrated that ethyl pyruvate is endowed with antioxidant and anti-inflammatory properties. It has been shown that small volumes of hypertonic saline solution (7.5%) improve hemodynamics, the microcirculation, and modulate the immune system. This study aimed to investigate the effects of ethyl pyruvate, hypertonic saline and lactated Ringer\'s solution on mesenteric microcirculation in a sepsis model induced by live Escherichia coli in rats. METHODS: Male Wistar rats were underwent an intravenous suspension of E. coli bacteria or submitted to the sham procedure. After 3h of bacteria infusion rats were randomized into: control, without treatment; treated with lactated Ringer\'s solution (4 mL/kg, i.v.); treated with lactated Ringer\'s solution (4mL/kg, i.v.) plus ethyl pyruvate (50mg/kg), and treated with hypertonic saline solution (7.5%, 4 mL/kg i.v.). At 24h after bacteria infusion leukocyte-endothelial interactions were investigated by intravital microscopy, and the expression of P-selectin and intercellular adhesion molecule (ICAM)- 1 evaluated by immunohistochemistry. White blood cell and platelet counts were determined at baseline, 3h and 24h after E. coli inoculation. RESULTS: Both non-treated and lactated Ringer\'s-treated groups exhibited an increase in the number of rolling leukocytes (~2.5-fold), adherent (~3.0-fold), and migrated cells (~3.5-fold) compared to sham. Treatment with Ringer\'s ethyl pyruvate solution reduced the number of rolling, adherent and migrated leukocytes to the levels attained in the sham group (p > 0.05). Similar effects were observed when animals were treated with hypertonic saline (p > 0.05). The expression of P-selectin and ICAM-1 significantly increased on mesenteric microvessels in non-treated group compared with sham (p < 0.001). All treatments reduced the expression of both adhesion molecules being ethyl pyruvate and hypertonic saline solution more effective than lactated Ringer\'s solution. Infusion of bacteria caused a significant leucopenia (3h), followed by a leucocytosis with granulocytosis (24h). There was an intense and progressive reduction in the number of platelets. No differences were observed after treatment with the different solutions. CONCLUSIONS: Data presented suggest that ethyl pyruvate and hypertonic saline solution (7.5%) efficiently reduce the inflammatory response at mesenteric microcirculation in an experimental model of sepsis induced by live E. coli associated, at least in part, with a down-regulation of P-selectin and ICAM-1

A solução salina hipertônica (SSH) é reconhecida por seu efeito ressuscitador em animais com choque hipovolêmico, aumentando a passagem de fluidos de outros órgão e tecidos para a corrente circulatória. Bovinos acometidos com acidose láctica ruminal aguda (ALRA) freqüentemente apresentam quadros de variável desidratação devido à passagem de fluidos do organismo para o rúmen, além do estabelecimento de acidose sistêmica, devido à absorção de ácido láctico ruminal. Como o SSH aumenta o volume de urina excretada seria plausível o efeito desta solução na excreção de íons H+ e lactato na urina de animais com ALRA. Doze bovinos machos, mestiços e de um ano de idade foram utilizados para avaliar o efeito do tratamento adicional de SSH sobre a (ALRA). Após período de adaptação e implantação de cânula no rúmen os animais foram submetidos à indução de ALRA por meio de quantidade calculada de sacarose administrada diretamente no rúmen. Após 20 horas da indução os animais foram aleatoriamente divididos em dois grupos iguais. Um deles (SSH) foi tratado com 5 mL/kg P.V. de uma solução de SSH a 7,5 %, dentro de 15 min, e 20 mL/kg/P.V. de solução salina isotônica (SSI) no decorrer dos próximos 165 minutos. Foram ainda retirados 5 L de conteúdo ruminal e adicionado igual quantidade de água no rúmen. O outro grupo (SSI) foi medicado da mesma forma, com exceção do SSH que foi substituído por 5 mL/kg PV de SSI. Variáveis foram mensuradas no momento 0 (MO), na 20 h (M20h) e no decorrer dos tratamentos com ISS ou SSH (M30´, M60´, M120´e M180´). Ao término desses tratamentos todos os animais foram medicados com quantidades calculadas de solução de 1,3 % de bicarbonato de sódio IV. A acidose ruminal obtida pela indução foi de grau médio a moderado, a acidose sistêmica e a intensidade de desidratação de graus moderados. A adição de água no rúmen nos primeiros 30 min. uma ligeira acidemia (0,03 graus de pH) acompanhada de discreta hipercapnia, além de gerar um aumento significativo na osmolalidade sérica favorecendo a absorção de fluidos do rúmen para a corrente sanguínea, avaliada pelo aumento de osmolalidade ruminal. Essa condição melhorou temporariamente o restabelecimento do volume globular. O tratamento com SSH ainda permitiu a maior excreção urinária, acompanhada de aumento da taxa de filtração glomerular e maiores eliminações de íons H+, lactato e fósforo. Existiu uma alta relação positiva entre a excreção de fósforo e pH urinários (R2= 0,562). O tratamento com SSH não gerou quaisquer reações colaterais. Os presentes resultados indicam que é vantajoso e adequado o tratamento de quadros de ALRA com SSH, em relação ao protocolo com SSI. / Hypertonic saline solution (HSS) is known by causing a resurrection effect in animals with hypovolemic shock, through the passage of fluids from other organs and tissues to the blood stream. Cattle with acute rumen lactic acidosis (ARLA) usually present different degrees of dehydration, caused by the migration of fluids from the body toward the rumen, besides the development of systemic acidosis by the absorption of ruminal lactic acid. As the HSS increases the volume of excreted urine would be plausible to suggest that this solution could enhance the urinary excretion of H+ and lactate in cattle with ARLA. Twelve yearling, cross-bred, male cattle were used to evaluate the effect of the additional treatment with HSS on cattle with ARLA. After an adaption period, when a rumen cannula was implanted, the animals were submitted to an induction of ARLA by a calculated amount of sucrose into the rumen. Twenty hours later the cattle were randomly divided in two equal groups. The 1st group was treated with 5 mL/kg BW with 7.5 % HSS, within 15 min, and 20 mL/ kg BW of isotonic saline solution (ISS) for the next 165 min. Five litres of rumen fluid was withdraw and equal volume of water was added into the rumen. The following group was treated equally, but the HSS that was changed to the same volume of ISS. Several variables were measured at different times of the experiment. At the end of this protocol all animals were treated with calculated amounts of 1.3% sodium bicarbonate solution IV. The induction caused a medium to moderate ruminal acidosis, and a moderate degree of systemic acidosis and dehydration. The administration of water caused a sharp decrease in the rumen osmolality. The treatment with HSS caused a mild academia (0.03 degree of pH) followed by a discrete hypercapnia, besides generating a significant increase in the serum osmolality, which favours the rumen fluid absorption into the blood stream. This condition improved temporarily the recovering of globular volume. The treatment with HSS also increased the urinary volume excreted followed by the improvement of the glomerular filtration ratio and the global excretion of H+, lactate and phosphorus. A high positive relationship was found between the excretion of urinary phosphorus and urine pH (R2 = 0,562). No side effects were seen in cattle treated with HSS. The present results show that is beneficial and adequate the treatment of ARLA with HSS, as compared to the protocol with ISS.