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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Phosphatase and tensin homolog deleted on chromosome Ten (PTEN) as a molecular target in lung epithelial wound repair and protection

Lai, Ju-Ping 15 April 2008 (has links)
No description available.
62

Intestinal effects of lung recruitment maneuvers

Claesson, Jonas January 2007 (has links)
Background and aims: Lung recruitment maneuvers (brief episodes of high airway pressure) are a modern treatment alternative to achieve open lung conditions under mechanical ventilation of patients with acute lung injury. It is well known that positive pressure ventilation with high airway pressures cause negative circulatory effects, and that the effects on regional vascular beds can be even more pronounced than the systemic effects. Hypoperfusion of the mesenteric vascular bed can lead to tissue ischemia and local inflammation. This intestinal inflammation has been associated with subsequent development of multiple organ dysfunction syndrome, a syndrome that still carries a high mortality and is a leading cause of death for intensive care patients. The aim of this thesis was therefore to investigate whether lung recruitment maneuvers would cause negative effects on mesenteric circulation, oxygenation or metabolism. Methods and results: In an initial study on ten patients with acute lung injury, we could demonstrate a trend towards a decreased gastric mucosal perfusion during three repeated lung recruitment maneuvers. To more closely examine this finding, we set up an oleic acid lung injury model in pigs, and in our second study we established that this model was devoid of inherent intestinal effects and was adequate for subsequent studies of intestinal effects of lung recrutiment maneuvers. In the acute lung injury model, we also tested the effect of an infusion of a vasodilating agent concurrent with the recruitment maneuvers, the hypothesis being that a vasodilating agent would prevent intestinal vasoconstriction and hypoperfusion. We could show that three repeated lung recruitment maneuvers induced short term negative effects on mesenteric oxygenation and metabolism, but that these findings were transient and short lasting. Further, the effects of prostacyclin were minor and opposing. These findings of relative little impact on the intestines of lung recruitment maneuvers, lead us to investigate the hypothesis that repeated recruitment maneuvers maybe could elicite a protective intestinal preconditioning response, a phenomenon previously described both in the rat and in the dog. However, in our fourth study, using both classical ischemic preconditioning with brief periods of intestinal ischemia or repeated lung recrutiment maneuvers, we could not demonstrate the phenomenon of intestinal preconditioning in the pig. Conclusions: We conclude, that from a mesenteric point of view, lung recruitment maneuvers are safe, and only induce transient and short lasting negative effects. We also conclude that the cause of the minor effects of lung recruitment maneuvers is not dependent on intestinal preconditioning.
63

Efeitos da ventilação em posição prona na lesão pulmonar aguda leve induzida por injeção de lipopolysaccharide intraperitoneal em ratos Wistar

Bianchi, Aydra Mendes Almeida 09 March 2015 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-02-26T13:39:38Z No. of bitstreams: 1 aydramendesalmeidabianchi.pdf: 1447064 bytes, checksum: 5e432ac627c643fd1832440690fe8539 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-03-03T14:05:06Z (GMT) No. of bitstreams: 1 aydramendesalmeidabianchi.pdf: 1447064 bytes, checksum: 5e432ac627c643fd1832440690fe8539 (MD5) / Made available in DSpace on 2016-03-03T14:05:06Z (GMT). No. of bitstreams: 1 aydramendesalmeidabianchi.pdf: 1447064 bytes, checksum: 5e432ac627c643fd1832440690fe8539 (MD5) Previous issue date: 2015-03-09 / FAPEMIG - Fundação de Amparo à Pesquisa do Estado de Minas Gerais / Introdução: A posição prona tem sido estudada como estratégia ventilatória em pacientes com síndrome do desconforto respiratório agudo. Seus benefícios, inclusive com redução da mortalidade, estão bem estabelecidos nas formas graves da síndrome, mas não em formas mais leves. Objetivo: Investigar o efeito da posição prona nas trocas gasosas, inflamação e histologia pulmonar, em modelo experimental de lesão pulmonar aguda leve em ratos. Métodos: A lesão pulmonar aguda foi induzida em ratos Wistar, machos, adultos, através da injeção de lipopolissacarídeo da Escherichia coli (5 mg/Kg). Após 24 h, os animais com PaO2/FIO2 entre 200 e 300 mmHg foram anestesiados e randomizados dentro de 2 grupos de acordo com a sua posição durante a ventilação (prona [n=6] e supina [n=6]). Ambos os grupos foram comparados com um grupo controle [n=5] que recebeu solução salina a 0,9% intraperitoneal e foi ventilado em posição supina. Todos os grupos foram ventilados por 1 h em modo ventilatório volumecontrolado, com volume corrente de 6 ml/Kg, frequência respiratória de 80 irpm, pressão positiva ao final da expiração de 5 cmH2O e uma fração inspirada de oxigênio de 1. Resultados: O escore de lesão pulmonar foi significativamente maior no grupo LPS-supino, em comparação com os grupos LPS-prono e controle (0,32 ± 0,03; 0,17 ± 0,03 e 0,13 ± 0,04, respectivamente) (p < 0,001), devido a uma maior infiltração de neutrófilos no espaço intersticial e maior presença de debris proteicos na luz alveolar. Esta maior lesão pulmonar no grupo LPS-supino foi observada tanto nas regiões pulmonares dependentes da gravidade (dorsal no grupo supino e ventral no grupo prono – 0,34 ± 0,05 e 0,22 ± 0,04, respectivamente) (p < 0,05), quanto nas não dependentes (ventral no grupo supino e dorsal no grupo prono – 0,29 ± 0,04 e 0,13 ± 0,04, respectivamente) (p < 0,05). O contagem de neutrófilos no LBA foi maior no grupo LPS-supino, comparado com os grupos LPS prono e controle. Não houve diferenças significativas na relação peso úmido/peso seco e nas trocas gasosas entre os três grupos. Conclusões: Neste modelo experimental de lesão pulmonar aguda leve extrapulmonar, a ventilação em posição prona por 1 hora, quando comparada com a ventilação em posição supino, associou-se a menor lesão e inflamação pulmonar, mas sem impacto na oxigenação arterial e no edema pulmonar. / Introduction: Prone position has been studied as a ventilator strategy among patients with acute respiratory distress syndrome. The benefits of prone position ventilation, including reduction in the mortality, are well demonstrated in the severe but not in milder forms of this syndrome. We therefore investigated the effects of the prone position on arterial blood gases, lung inflammation and histology in an experimental model of mild acute lung injury in rats. Methods: Acute lung injury was induced in adult male Wistar rats by intraperitoneal Escherichia coli lipopolysaccharide injection (5 mg/kg). After 24h, the animals with PaO2/FIO2 between 200 and 300 mmHg were anesthetized and randomized into 2 groups according to their position during ventilation (prone [n=6] and supine [n=6]). Both groups were compared to a control group (n=5) that received intraperitoneal saline and was ventilated in the supine position. All of the groups were ventilated for 1h with volume-controlled ventilation mode, with tidal volume of 6 ml/kg, respiratory rate of 80 breaths/min, positive end-expiratory pressure of 5 cmH2O, and an inspired oxygen fraction of 1. Results: Significantly higher lung injury scores were observed in the LPS-supine group compared to LPS-prone and control groups (0.32 ± 0.03; 0.17 ± 0.03 and 0.13 ± 0.04, respectively) (p<0.001), mainly due to a higher neutrophil infiltration level in the interstitial space and more proteinaceous debris in the airspaces. Similar differences were observed when the gravitational dependent lung regions (dorsal in the supine group and ventral in the prone group – 0.34 ± 0.05 and 0.22 ± 0.04, respectively) (p < 0.05) and non-dependent lung regions (ventral in the supine group and dorsal in the prone group – 0.29 ± 0.04 and 0.13 ± 0.04, respectively) (p < 0.05) were analyzed separately. The BAL neutrophil content was also higher in the LPS-supine group compared to the LPSprone and control groups. There were no significant differences in the wet/dry ratio and gas exchange levels among the three groups. CONCLUSIONS: In this experimental extrapulmonary mild acute lung injury model, prone position ventilation for 1 hour, when compared with supine position ventilation, was associated with lower lung inflammation and injury, but without any impact on arterial oxygenation and lung edema.
64

Die Rolle des Transkriptionsfaktors NF-κB bei der mechanischen Dehnung von pulmonalen Strukturzellen

Maser, Franziska 05 May 2010 (has links)
Obwohl die künstliche bzw. mechanische Beatmung bei der Therapie von ALI / ARDS eine wichtige und bedeutende Rolle spielt, kann sie selbst eine akute Lungen-schädigung auslösen oder bestehende pulmonale Beeinträchtigungen verstärken. Zentraler Schädigungsmechanismus ist die alveoläre Überdehnung durch hohe Ti-dalvolumina. Selbst bei der Anwendung kleiner, protektiver Tidalvolumina in Lungen mit einem nur geringen Anteil belüfteter Alveolen kann es in diesen zu alveolärer Überdehnung kommen. Diese Überdehnung führt einerseits zu mechanisch induzier-te Apoptose sowie Nekrose und andererseits zu einer mechanisch induzierten Ver-änderung der Mediatorenfreisetzung hin zu einem pro-inflammatorischen Muster. Da der Transkriptionsfaktor NF-κB zahlreiche Mediatoren aktiviert bzw. von ihnen beeinf-lusst werden kann, nimmt er in diesem Geschehen eine ganz besondere Schlüssel-position ein. In der vorliegenden Arbeit wird der Hypothese nachgegangen, ob die NF-κB-Aktivierung bei der mechanischen Dehnung und dem daraus resultierenden inflam-matorischen Verhalten von pulmonalen Strukturzellen verändert wird und in wie weit ein Zusammenhang zwischen Dehnung, Zellschädigung und NF-κB besteht. Dafür wurden sowohl frisch isolierte alveoläre Ratten-Typ-II Zellen, Zellen der hu-man-alveolaren Epithelzelllinie A549 sowie Lungen- Fibroblasten der Zell-Linie Wi 38 untersucht. Alle drei Zellarten wurden auf einem speziellen elastischen Silikonboden von 6er-Well-Platten inkubiert, wo sie mit Hilfe des Flexercell-Stretch-Gerätes (FX 3000) als Zellmonolayer equibiaxial für 24 Stunden gedehnt wurden. Auch die zeitliche Abhängigkeit der NF-κB-Expression von der mechanischen Deh-nung wurde untersucht. Dabei konnte festgestellt werden, dass ein Zusammenhang zwischen NF-κB-Aktivierung, Zellschädigung und mechanischer Dehnung existiert. Wobei bei unter-schiedlichen Zellarten auch variierende Ergebnisse beobachtet werden konnten. Im Zusammenhang mit anderen aus unserer Forschungsgruppe und in der Literatur stammenden Erkenntnissen konnte so eine Verknüpfung zwischen NF-κB-Aktivierung, Zytokinfreisetzung und inflammatorischer pulmonaler Reaktion nachge-wiesen werden.
65

The Beneficial Effects of Hypercapnia, and the Detrimental Effects of Peroxynitrite, in Chronic Neonatal Lung Injury

Masood, Azhar 10 January 2012 (has links)
Bronchopulmonary dysplasia (BPD) is a chronic neonatal lung injury (CNLI) affecting infants of < 32 weeks gestation, which has a significant associated morbidity and mortality. The hallmarks of BPD as seen in the current era are arrested alveologenesis and parenchymal thickening. Those most severely affected may develop pulmonary hypertension which worsens the prognosis. No effective preventive therapy exists. Generation of damaging reactive oxygen species is implicated in its development. The more recently recognized reactive nitrogen species may also contribute to this disease. Thus, there is considerable interest in preventive antioxidant therapies, but results to date have not been promising. Newborn rats, exposed to 60% O2 for 14 days, develop a parenchymal injury and pulmonary hypertension that resembles the morphological features of human BPD. Previous studies have shown that following exposure to 60% O2, a pulmonary influx of neutrophils is followed by that of macrophages. Inhibiting the influx of neutrophils prevents the generation of reactive oxygen species, while simultaneously enhancing postnatal lung growth. Other interventions have shown that development of pulmonary hypertension is dependent upon increases in both 8-isoprostane and its downstream regulator of vascular tone, endothelin-1. Gentler ventilation strategies, incorporated to minimize induction of stretch-mediated pro-inflammatory cytokines, have shown benefits of permissive hypercapnia in adult lung injury. Multicentre clinical trials of permissive hypercapnia in neonates have not shown benefit. Therapeutic hypercapnia has been demonstrated to have a protective effect of PaCO2 in both acute studies of ventilator-induced and ischemia-reperfusion injuries in animal models. In the studies reported herein, therapeutic hypercapnia was found to completely protect against CNLI and attenuate 60% O2-induced macrophage-derived protein nitration. The likely nitrating agent was macrophage-derived peroxynitrite. The critical role of peroxynitrite, in the development of chronic neonatal lung injury in this model, was confirmed using a peroxynitrite decomposition catalyst. This protected against the impairments of alveolarization and of pulmonary vascularization induced by 60% O2. These results suggest a more significant role for reactive nitrogen species than previously recognized. Finally, preliminary evidence is presented supporting a role for neutrophil-derived elastase in initiating the macrophage influx in the lungs, required for peroxynitrite generation, during 60% O2-mediated injury.
66

Plasminogen Activator Inhibitor-1 (PAI-1) and Activated Protein C (aPC) Modulation Mechanisms of Pseudomonas aeruginosa Induced Pulmonary Edema / Mécanismes de Modulation par PAI-1 et aPC de l’Oedeme Pulmonaire induit par le Pseudomonas aeruginosa

Lafargue, Mathieu 10 December 2012 (has links)
Une coagulopathie aigue endogène (EAC) est présente chez 25% des patients de traumatologie dès leur arrivée. Des résultats d’études récentes montrent que cette EAC est liée à l’activation de la voie de la protéine C (aPC). Quelques heures après, se développe un état pro-coagulant associant un niveau abaissé d’aPC et un taux plasmatique élevé de l’inhibiteur de l’activateur du plasminogene (PAI-1). Nous trouvons que l’incidence des pneumopathies associées à la ventilation est significativement augmentée chez ces patients sans toutefois connaître le rôle exact de ces anomalies de coagulation. Basé sur cette hypothèse central de susceptibilité augmentée a l’infection et plus particulièrement aux pneumopathie a P.aeruginosa (PA) le but de ce travail est d’identifier les mécanismes par lesquels PAI-1 et aPC peuvent moduler la perméabilité de la barrière alveolo capillaire et ceci a travers 3 objectifs spécifiques1 – Objectif 1 : déterminer les mécanismes par lequel PA augmente la perméabilité endothéliale. 2 – Objectif 2 : déterminer le rôle d’aPC dans la modulation des effets de PA sur l’œdème pulmonaire lésionnel.3 – Objectif 3 : déterminer le rôle de PAI-1 dans la modulation des effets de PA sur l’œdème pulmonaire lésionnel.En utilisant un inhibiteur spécifique des petites GTPases nous démontrons le rôle centrale joué par RhoA dans le développement de l’œdème pulmonaire induit par PA. PAI-1 et aPC sont impliquées dans le mécanisme lésionnel pulmonaire. aPC et l’inhibition de la voie du RhoA attenue le développement de l’œdème pulmonaire et diminue la dissémination systémique bactérienne. Cependant le blocage invivo de la voie de PAI-1 est associé à une surmortalité et à une augmentation de la charge bactérienne suggérant un rôle de PAI-1 dans l’activation de la réponse inflammatoire nécessaire a l’éradication de PA / A clinically significant acute endogenous coagulopathy (EAC) is present in 25% of major trauma patients upon arrival in the emergency department, before any fluid resuscitation. Results from recent clinical studies indicate that EAC is primarily caused by the activation of the anticoagulant protein C pathway. Several hours later, there is the development of a systemic procoagulant activity associated with low plasma levels of activated protein C (aPC) and an inhibition of the fibrinolysis caused by elevated plasma levels of plasminogen activator inhibitor 1 (PAI-1). We have found that the incidence of ventilator-associated pneumonia (VAP) is significantly increased in trauma patients with these coagulation abnormalities [6, 9]. However, whether these coagulation abnormalities play a mechanistic role in the increased susceptibility to nosocomial lung infection observed after severe posttraumatic hemorrhage is unknown. Thus, the central hypothesis is that the increased susceptibility to P. aeruginosa (PA) pneumonia following severe trauma with tissue hypoperfusion is mediated in part by these posttraumatic coagulation abnormalities within the airspaces of the lung. Specifically, in this work, we will identify through 3 specific aims the mechanisms by which PAI-1 and aPC modulate PA–mediated increase in alveolar-capillary barrier permeability.1 - Specific Aim 1: To determine the mechanisms by which PA increases lung endothelial permeability.2 - Specific Aim 2 : To determine the Role of aPC in modulating the effect of PA on the lung endothelial barrier function3 - Specific Aim 3 : To determine the Role of PAI-1 in modulating the effect of PA on the lung endothelial barrier functionIn the present work, we demonstrated the central role small GTPases RhoA plays in the increase of permeability induced by pseudomonas infection. PAI-1 and aPC are deeply involved in the control of early lung inflammation. aPC and inhibition of the RhoA pathway attenuates the development of pulmonary edema and decrease in the systemic dissemination of P. aeruginosa. However, in vivo disruption of PAI-1 signalling is associated with higher mortality at 24 h and significant increase in the bacterial burden suggesting that PAI-1 is required for the activation of the innate immune response necessary for the eradication of PA from the distal airspaces of the lung
67

O eixo LTB4/MYD88 na inflamação estéril e na sepse em modelos experimentais de diabetes. / The LTB4/MyD88 axis in sterile inflammation and sepsis in experimental models of diabetes.

Ribeiro Junior, Luciano Filgueiras 18 August 2014 (has links)
A diabetes tipo 1 (DT1) está associada `a inflamação estéril (IE) e maior susceptibilidade a sepse. A sepse induz a síndrome da resposta inflamatória sistêmica (SIRS) e a inflamação pulmonar aguda (ALI). O leucotrieno (LT) B4 produzido condições inflamatórias induz a expressão de MyD88 em macrófagos (MA). Hipotetizamos que a DT1 induz a síntese de LTB4 promovendo a IE e isto contribui para SIRS, susceptibilidade a sepse e ALI. Os diabéticos apresentaram níveis elevados de LTB4 e IL-1b no soro e seu MA expressaram mais MyD88/STAT-1. A expressão de STAT-1 foi induzida por c-Jun de forma dependente de LTB4. O tratamento com insulina restaurou os níveis de LTB4 e STAT-1/MyD88 e a inibição de LTB4 restaurou os níveis de MyD88 e IL-1b. Na sepse, a inibição de 5LO prolongou a sobrevida dos diabéticos e diminuiu a SIRS menos IL-1b e IL-10 no soro e TNF-a e IL-1b na cavidade peritoneal. O pulmão dos diabéticos apresentaram ALI menos intensa que se correlacionou com um altos níveis de SOCS-1, baixos níveis de MyD88 e falha na ativação de NFkB nos macrófagos alveolares. / Type 1 diabetes (T1D) is associated with sterile inflammation (SI) and increased sepsis susceptibility. Sepsis induces Systemic Inflammatory Response Syndrome (SIRS) and Acute Lung Injury (ALI). Leukotriene (LT) B4 is produced in inflammatory conditions and induces MyD88 expression in macrophages (MA). We hypothesized that T1D induce LB4 that promotes SI contributing to SIRS, sepsis susceptibility and ALI. Diabetics presented higher levels of LTB4 and e IL-1b in the serum and MA expressed more MyD88/STAT-1. STAT-1 expression was induced by c-Jun on LTB4 dependent manner. Insulin treatment restored LTB4 and STAT-1/MyD88 levels and inhibition of LTB4 restored MyD88 and IL-1b levels. During sepsis, 5LO inhibition increased diabetics survival and inhibited SIRS- lower levels of IL-1b and IL-10 in the serum and TNF-a and IL-1b in the peritoneal cavity. Lungs from diabetics presented milder ALI that correlated with high levels of SOCS-1, low levels of MyD88 and impaired NFkB activation in alveolar macrophages.
68

O papel da heme oxigenase 1 na síndrome do desconforto respiratório agudo associada à malária. / The role of heme oxygenase 1 in malaria-associated acute respiratory distress syndrome.

Pereira, Marcelo Luís Monteiro 25 August 2016 (has links)
A malária é uma doença causada pelo parasita do gênero Plasmodium e que foi responsável por cerca de 440.000 mortes em 2015. A síndrome do desconforto respiratório agudo (SDRA) é uma das principais complicações clínicas da malária. O modelo murino DBA/2 reproduz os sinais clínicos da SDRA observados em humanos, quando infectado com o Plasmodium berghei ANKA. Além disso, altos níveis da enzima heme oxigenase 1 (HO-1) foram observados em casos de malária cerebral e em SDRA em humanos. Os nossos dados indicam que os níveis da HO-1 estão aumentados em camundongos que desenvolvem SDRA associada à malária (SDRA-AM). Adicionalmente, a droga indutora de HO-1 (hemina) aumentou a sobrevivência e preveniu a SDRA-AM. Verificou-se também uma redução na permeabilidade pulmonar e nos níveis de VEGF, além de uma melhoria nos parâmetros respiratórios em animais tratados com hemina. Assim sendo, a indução da HO-1 antes do desenvolvimento da SDRA-AM é protetora e assim, a HO-1 pode ser um alvo de novos fármacos, como forma de prevenir o desenvolvimento da SDRA-AM em humanos. / Malaria is a serious disease, caused by the parasite of the genus Plasmodium, which was responsible to 440,000 deaths in 2015. Acute lung injury/ acute respiratory distress syndrome (ALI/ARDS) is one of the main clinical complications in severe malaria. The murine model DBA/2 reproduces the clinical signs of ALI/ARDS observed in humans, when infected with Plasmodium berghei ANKA. Additionally, high levels heme oxygenase 1 (HO-1) were reported in cases of cerebral malaria and in ALI/ARDS in humans. Our data have indicated that the HO-1 levels are increased in mice that develop malaria associated ALI/ARDS (MA-ALI/ARDS). Additionally, a HO-1 inducing drug (hemin) increased the survival rate and prevented mice from developing MA-ALI/ARDS in treated mice. Also, there was a decrease in the lung permeability and in lung VEGF levels, and an amelioration of respiratory parameters. Therefore, the induction of HO-1 before the development of MA-ALI/ARDS is protective, making this enzyme a possible target of new drugs to prevent the development of MA-ALI/ARDS in humans.
69

Comparação entre duas soluções de recondicionamento pulmonar em pulmões humanos não-aceitos para transplante em modelo de avaliação e recondicionamento pulmonar ex vivo / Comparison between two pulmonary reconditioning solution in human lungs non-accepted for transplantation with an ex vivo lung assessment and reconditioning model

Fernandes, Lucas Matos 18 August 2015 (has links)
INTRODUÇÃO: O transplante pulmonar é terapia reconhecida de tratamento de doenças terminais pulmonares. Os pulmões, entretanto, são muito susceptíveis às transformações hormonais e hidroeletrolíticas ocorridas no doador após a morte encefálica. As baixas taxas de aproveitamento dos pulmões alavancam pesquisas e meios de utilizar pulmões considerados nãoideais. Um desses modelos é o recondicionamento pulmonar ex-vivo concebido por Steen, no qual se utiliza uma solução hiperosmolar (Steen Solution®) para avaliação e melhora dos pulmões doados. Consideramos que o desenvolvimento de uma solução de recondicionamento pulmonar produzida no Brasil seria conveniente aos serviços de transplante e aos pacientes. Foram comparadas a solução de recondicionamento Steen Solution® e uma solução de fabricação nacional em modelo de ex vivo de pulmões humanos não aceitos para transplante, através da avaliação da mecânica ventilatória, hemodinâmica, trocas gasosas e histologia. MÉTODOS: Foram utilizados 16 pulmões de doadores em morte encefálica, considerados inadequados para o transplante pulmonar. Os pulmões foram submetidos à captação habitual e acondicionados sob isquemia fria por 10 horas. Após este período, os pulmões foram designados, por sorteio, para reperfusão com a solução padrão (Steen solution®) ou a solução nacional por 1h em modelo ex vivo. A lesão pulmonar foi estudada através de parâmetros gasométricos, resistência pulmonar e complacência pulmonar. Foram medidos os pesos em três tempos e relação peso úmido/peso seco após a reperfusão para avaliação de edema. A partir de biópsias seriadas era calculado um score de lesão tecidual e grau de apoptose. RESULTADOS: A capacidade de oxigenação foi de 498,00 ± 37,53 mmHg no grupo STEEN e 521,00 ± 55,43 mmHg no grupo SRNac (p = 0,348). A capacidade relativa de oxigenação calculada ao final do recondicionamento foi 501,37 ± 207,77 no grupo STEEN e 470,30 ± 232,41 no grupo SRNac (p=0,782). Os pesos dos pulmões nos três momentos de avaliação foram: início da isquemia: STEEN = 1.026 ± 451 g, SRNac = 745 ± 282 g (p = 0,180); fim da isquemia: STEEN = 998 ± 391 g, SRNac = 738 ± 316 g (p = 0,184); e fim da reperfusão: STEEN = 1.097 ± 526 g, SRNac = 743 ± 248 g (p = 0,163). A relação peso úmido/peso seco foi 3,63 ± 1,26 no grupo SRNac e 2,06 ± 0,28 no grupo STEEN (p = 0,009). A resistência vascular pulmonar foi 787,99 ± 367,23 dina.s.cm-5 no grupo STEEN e 1.026,81 ± 1.112,53 dina.s.cm-5 no grupo SRNac (p = 0,575). A complacência pulmonar média foi 46,75 ± 20,99 mL/cmH2O no grupo STEEN e 49,74 ± 26,11 cmH2O no grupo SRNac (p = 0,809). O Escore de Lesão Pulmonar foi: STEEN = 4,38 ± 1,51 e SRNac = 4,50 ± 1,77 (p = 0,881). O número de células apoptóticas foi: STEEN = 2,4 ± 2,0 cel/mm2 e SRNac = 4,8 ± 6,9 cel/mm2 (p = 0,361). CONCLUSÕES: Os pulmões reperfundidos com a solução de recondicionamento de fabricação nacional apresentaram características morfológicas e funcionais similares aos que foram reperfundidos com a solução STEEN®, apesar do maior edema encontrado no grupo da solução nacional / INTRODUCTION: Lung transplantation is routine treatment of end-stage lung diseases. The lungs, however, are very susceptible to hormonal and electrolyte changes occurred in the donor after brain death. The low recovery rates of the lungs leverage researches and ways to use lungs considered non-ideal. One such model is the lung ex vivo reconditioning designed by Steen, in which using a hyperosmolar solution (Steen Solution®) for evaluation and improvement of donor lungs. We believe that the development of a pulmonary reconditioning solution produced in Brazil would be convenient to transplantation service and patients. Were compared the standard Steen Solution® and a national manufacturing solution in ex vivo model with human lungs not accepted for transplant, through the evaluation of respiratory mechanics, hemodynamics, gas exchange and histology. METHODS: 16 brain-dead donors lungs, considered unsuitable for lung transplantation, were used. The lungs were harvest as usual, packed and stored in cold ischemia for 10 hours. After this period, the lungs were appointed by randomization to reperfusion with the standard solution (Steen Solution®) or national solution for 1 h in ex vivo model. Lung injury was accessed by blood gas parameters, lung resistance and lung compliance. The weights were measured in three times and the after reperfusion wet weight / dry weight ratio for evaluation of edema. The degree of apoptosis and tissue injury score was calculated from serial biopsies. RESULTS: The oxygenation capacity was 498.00 ± 37.53mmHg in STEEN group and 521.00 ± 55.43mmHg in SRNac group (p = 0.348). The relative oxygenation capacity calculated at the end of the reconditioning was 501.37 ± 207.77 in the STEEN group and 470.30 ± 232.41 in the SRNac group (p = 0.782). The weights of lungs in the three stages of evaluation were: onset of ischemia: STEEN = 1,026 ± 451g, SRNac = 745 ± 282g (p = 0.180); end of ischemia: STEEN = 998 ± 391g, SRNac = 738 ± 316g (p = 0.184); and the end of reperfusion: STEEN = 1,097 ± 526g, SRNac = 743 ± 248g (p = 0.163). The wet weight / dry weight ratio was 3.63 ± 1.26 in SRNac group and 2.06 ± 0.28 in STEEN group (p = 0.009). Pulmonary vascular resistance was 787.99 ± 367.23dina.s.cm-5 in STEEN group and 1026.81 ± 1112.53dina.s.cm-5 in SRNac group (p = 0.575). The Lung Injury Score was: STEEN = 4.38 ± 1.51 and SRNac = 4.50 ± 1.77 (p = 0.881). The number of apoptotic cells was: STEEN = 2.4 ± 2.0 cells / mm 2 and SRNac = 4.8 ± 6.9 cells / mm2 (p = 0.361). CONCLUSIONS: The lungs reperfused with national manufacturing reconditioning solution presented morphological and functional characteristics similar to those reperfused with STEEN® solution despite the greater edema found in the group of national solution
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Participação da corticosterona na inflamação aguda pulmonar de ratos com baixo peso ao nascer. / Influence of corticosterone on acute lung inflammation of low birth weight rats.

Gil, Noemi Lourenço 15 February 2017 (has links)
A desnutrição no período gestacional pode comprometer o desenvolvimento fetal e a maturação do sistema imune. Ratos Wistar de 12 semanas com baixo peso ao nascer, oriundos de mães desnutridas durante a gestação, apresentam resposta inflamatória pulmonar reduzida, e concentração de corticosterona circulante elevada. Este modelo foi submetido a adrenalectomia e reposição de corticosterona em doses fisiológicas, e em seguida, induziu-se lesão pulmonar aguda com LPS. Os resultados obtidos mostraram que a redução de corticosterona aumentou o infiltrado de neutrófilos e de mediadores inflamatórios no pulmão de animais com baixo peso ao nascer. Quanto a regulação da corticosterona, observou-se que a expressão pulmonar dos receptores de glicocorticoides apresentou-se reduzida nos animais de baixo peso ao nascer, entretanto, a redução de corticosterona promoveu o aumento da expressão dos receptores. É possível concluir que a corticosterona está envolvida com a reduzida resposta inflamatória pulmonar desenvolvida por animais de baixo peso ao nascer. / The malnutrition during pregnancy may impair the fetal development and the maturation of immune system. Wistar rats with 12 weeks-old with low birth weigt present reduced lung inflammatory response, and increased circulating levels of corticosterone. This model was subjected to adrenalectomy and corticosterone replacement in phyological levels, and the acute lung injury by LPS was induced. The results obtained showed an increase in neutrophil infiltration into lung tissue, and increase of inflammatory mediators after reduction of corticosterone in low birth weight rats. The lung expression of glucocorticoid receptors was reduced in low birth weight rats, however, after reduction of corticosterone, the expression of receptors was incerased. The data showed that high levels of corticosterone are related to reduced acute lung inflammatory response developed by low birth weght rats.

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