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INTRODUCTION: Low muscle mass is a common condition in the critically ill population and is associated with adverse clinical outcomes. The primary aim of this study was to analyze the prognostic significance of low muscle mass using computed tomography (CT) scans in COVID-19 critically ill patients. A second objective was to determine the accuracy and agreement in low muscle mass identification using diverse markers compared to CT as the gold standard. METHODS: This was a prospective cohort study of COVID-19 critically ill patients. Skeletal muscle area at the third lumbar vertebra was measured. Clinical outcomes (intensive care unit [ICU] and hospital length of stay [LOS], tracheostomy, days on mechanical ventilation [MV], and in-hospital mortality) were assessed. Phase angle, estimated fat-free mass index, calf circumference, and mid-upper arm circumference were measured as surrogate markers of muscle mass. RESULTS: Eighty-six patients were included (mean age ± SD: 48.6 ± 12.9; 74% males). Patients with low muscle mass (48%) had a higher rate of tracheostomy (50 vs 20%, p = 0.01), prolonged ICU (adjusted HR 0.53, 95%CI 0.30-0.92, p = 0.024) and hospital LOS (adjusted HR 0.50, 95% CI 0.29-0.86, p = 0.014). Bedside markers of muscle mass showed poor to fair agreement and accuracy compared to CT-assessed low muscle mass. CONCLUSION: Low muscle mass at admission was associated with prolonged length of ICU and hospital stays. Further studies are needed to establish targeted nutritional interventions to halt and correct the catabolic impact of COVID-19 in critically ill patients, based on standardized and reliable measurements of body composition.

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Essa revisão apresenta considerações acerca da relevância das infecções de parasitos gastrintestinais (PGI) em ruminantes, abordando a importância de fármacos antiparasitários no controle das helmintoses e demais alternativas. Foi realizada uma abordagem conceitual e histórica sobre o controle de PGI e o processo de desenvolvimento da resistência parasitária. Como alternativa da baixa eficácia de medicamentos, foi feita uma descrição detalhada sobre o uso de óleos essenciais (OE) e de componentes bioativos no controle das PGI em ruminantes. A produção de OE de plantas, passa pela composição química, técnicas de extração dos componentes, mecanismo de ação e ensaios para validação da sua atividade terapêutica, incluindo sua ação anti-helmíntica. Este artigo traz, na sua segunda parte, uma descrição detalhada de duas espécies do gênero Mentha, com foco em sua biologia, composição química e mecanismos de ação de seus OE. Dentro desse tópico, as espécies Mentha vilosa e M. piperita são as mais estudadas, bem como os seus componentes majoritários e bioativos; carvone e limoneno. Ao final do documento, discutimos sobre a técnica de cromatografia gasosa e espectrometria de massas, que se faz obrigatória para a identificação de compostos presentes em OE. Incluímos ainda, o detalhamento sobre tecnologias de nanoemulsão e suas vantagens na confecção de formulações mais estáveis, menos tóx

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Essa revisão apresenta considerações acerca da relevância das infecções de parasitos gastrintestinais (PGI) em ruminantes, abordando a importância de fármacos antiparasitários no controle das helmintoses e demais alternativas. Foi realizada uma abordagem conceitual e histórica sobre o controle de PGI e o processo de desenvolvimento da resistência parasitária. Como alternativa da baixa eficácia de medicamentos, foi feita uma descrição detalhada sobre o uso de óleos essenciais (OE) e de componentes bioativos no controle das PGI em ruminantes. A produção de OE de plantas, passa pela composição química, técnicas de extração dos componentes, mecanismo de ação e ensaios para validação da sua atividade terapêutica, incluindo sua ação anti-helmíntica. Este artigo traz, na sua segunda parte, uma descrição detalhada de duas espécies do gênero Mentha, com foco em sua biologia, composição química e mecanismos de ação de seus OE. Dentro desse tópico, as espécies Mentha vilosa e M. piperita são as mais estudadas, bem como os seus componentes majoritários e bioativos; carvone e limoneno. Ao final do documento, discutimos sobre a técnica de cromatografia gasosa e espectrometria de massas, que se faz obrigatória para a identificação de compostos presentes em OE. Incluímos ainda, o detalhamento sobre tecnologias de nanoemulsão e suas vantagens na confecção de formulações mais estáveis, menos tóxicas aos hospedeiros e com potencial de aumentar a eficácia de fármacos contra as PGI, para o desenvolvimento de novos compostos fitoterápicos ecosustentáveis.(AU)

This review presents considerations about the relevance of gastrointestinal parasite (GIP) infections in ruminants, covering also the importance of antiparasitic drugs in the control of helminth infections and some other alternatives. This document describes a conceptual and historical view of the development of routine GIP control and the process of development of drug resistance. As an alternative to the low efficacy of some products, a detailed description was made of the use of essential oils (EO) and their bioactive compounds in the control of GIP in ruminants. The production of EO from plants, goes through the chemical composition, techniques of extraction of components, mechanism of action and assays for the validation of their activity, including the anthelmintic activity. The present document brings, in its second part, a more detailed description of two species of the genus Mentha, focusing on their biology, chemical composition and the mechanism of action of their EO. Within this topic, the species of Mentha vilosa and M. piperita are better studied, as well as their chemical composition and bioactive components carvone and limonene. At the end, it is discussed the gas chromatography and mass spectrometry techniques that are useful to identify compounds present in EO. It was also included the details about nanoemulsion technologies and their advantages in obtaining a more stable formulation, less toxic to the host, with a great potential to increase anthelmintic efficacy against GIP, for the development of new herbal bioactive and ecofriendly compounds.(AU)

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Essa revisão apresenta considerações acerca da relevância das infecções de parasitos gastrintestinais (PGI) em ruminantes, abordando a importância de fármacos antiparasitários no controle das helmintoses e demais alternativas. Foi realizada uma abordagem conceitual e histórica sobre o controle de PGI e o processo de desenvolvimento da resistência parasitária. Como alternativa da baixa eficácia de medicamentos, foi feita uma descrição detalhada sobre o uso de óleos essenciais (OE) e de componentes bioativos no controle das PGI em ruminantes. A produção de OE de plantas, passa pela composição química, técnicas de extração dos componentes, mecanismo de ação e ensaios para validação da sua atividade terapêutica, incluindo sua ação anti-helmíntica. Este artigo traz, na sua segunda parte, uma descrição detalhada de duas espécies do gênero Mentha, com foco em sua biologia, composição química e mecanismos de ação de seus OE. Dentro desse tópico, as espécies Mentha vilosa e M. piperita são as mais estudadas, bem como os seus componentes majoritários e bioativos; carvone e limoneno. Ao final do documento, discutimos sobre a técnica de cromatografia gasosa e espectrometria de massas, que se faz obrigatória para a identificação de compostos presentes em OE. Incluímos ainda, o detalhamento sobre tecnologias de nanoemulsão e suas vantagens na confecção de formulações mais estáveis, menos tóxicas aos hospedeiros e com potencial de aumentar a eficácia de fármacos contra as PGI, para o desenvolvimento de novos compostos fitoterápicos ecosustentáveis.

This review presents considerations about the relevance of gastrointestinal parasite (GIP) infections in ruminants, covering also the importance of antiparasitic drugs in the control of helminth infections and some other alternatives. This document describes a conceptual and historical view of the development of routine GIP control and the process of development of drug resistance. As an alternative to the low efficacy of some products, a detailed description was made of the use of essential oils (EO) and their bioactive compounds in the control of GIP in ruminants. The production of EO from plants, goes through the chemical composition, techniques of extraction of components, mechanism of action and assays for the validation of their activity, including the anthelmintic activity. The present document brings, in its second part, a more detailed description of two species of the genus Mentha, focusing on their biology, chemical composition and the mechanism of action of their EO. Within this topic, the species of Mentha vilosa and M. piperita are better studied, as well as their chemical composition and bioactive components carvone and limonene. At the end, it is discussed the gas chromatography and mass spectrometry techniques that are useful to identify compounds present in EO. It was also included the details about nanoemulsion technologies and their advantages in obtaining a more stable formulation, less toxic to the host, with a great potential to increase anthelmintic efficacy against GIP, for the development of new herbal bioactive and ecofriendly compounds.

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O presente artigo é um relato sobre uma fêmea de D. novemcinctus que foi capturada de forma imprevista, durante um projeto de avaliação sanitária de animais silvestres sinantrópicos do município de Toledo/PR (autorização Sisbio/Ibama n. 55109-1). Durante a avaliação física, amostras de fezes foram coletadas após defecação espontânea e encaminhadas para análise. O material foi submetido aos métodos de flutuação simples em solução hipersaturada de cloreto de sódio e centrífugo-flutuação em sacarose. Na leitura das lâminas obtidas pelo método de centrífugo-flutuação em sacarose, foram observadas estruturas com comprimento de aproximadamente 10µm, forma bicônica e um tampão em cada extremidade, compatíveis com esporocistos de Monocystis sp. Protozoários do filo Apicomplexa, os Monocystis sp., são geralmente parasitas de anelídeos, como as minhocas. Esse organismo é comumente correlato a pseudoparasitismo em vários animais, porém não foram encontrados relatos de pseudoparasitismo desse agente em tatus-galinhas, logo essa é a primeira descrição de Monocystis sp. em espécime de D. novemcinctus.(AU)

The present article is an account of a female of D. novemcinctus which was captured during a sanitary evaluation project of synanthropic wild animals of the municipality of Toledo/PR (license SISBIO/ICMBIO n°. 55109-1). During a physical evaluation, samples of feces were collected, after spontaneous defecation, and sent for analysis. The material was subjected to simple flotation methods in hypersaturated sodium chloride solution and centrifugal-flotation solutions in sucrose. In a test reading by the centrifugal-flotation method in sucrose, structures with approximately 10µm, biconical shape and one plate at each end were observed, compatible with sporocysts of Monocystis sp. Protozoa of the phylum Apicomplexa, like Monocystis sp., it is common parasitic annelids, such as worms. This organism is a correlate of pseudoparasitism in several animals but was not found to describe this product as an agent in nine banded armadillos, so this is a first description of Monocystis sp. in specimen of D. novemcinctus.(AU)

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O presente artigo é um relato sobre uma fêmea de D. novemcinctus que foi capturada de forma imprevista, durante um projeto de avaliação sanitária de animais silvestres sinantrópicos do município de Toledo/PR (autorização Sisbio/Ibama n. 55109-1). Durante a avaliação física, amostras de fezes foram coletadas após defecação espontânea e encaminhadas para análise. O material foi submetido aos métodos de flutuação simples em solução hipersaturada de cloreto de sódio e centrífugo-flutuação em sacarose. Na leitura das lâminas obtidas pelo método de centrífugo-flutuação em sacarose, foram observadas estruturas com comprimento de aproximadamente 10µm, forma bicônica e um tampão em cada extremidade, compatíveis com esporocistos de Monocystis sp. Protozoários do filo Apicomplexa, os Monocystis sp., são geralmente parasitas de anelídeos, como as minhocas. Esse organismo é comumente correlato a pseudoparasitismo em vários animais, porém não foram encontrados relatos de pseudoparasitismo desse agente em tatus-galinhas, logo essa é a primeira descrição de Monocystis sp. em espécime de D. novemcinctus.(AU)

The present article is an account of a female of D. novemcinctus which was captured during a sanitary evaluation project of synanthropic wild animals of the municipality of Toledo/PR (license SISBIO/ICMBIO n°. 55109-1). During a physical evaluation, samples of feces were collected, after spontaneous defecation, and sent for analysis. The material was subjected to simple flotation methods in hypersaturated sodium chloride solution and centrifugal-flotation solutions in sucrose. In a test reading by the centrifugal-flotation method in sucrose, structures with approximately 10µm, biconical shape and one plate at each end were observed, compatible with sporocysts of Monocystis sp. Protozoa of the phylum Apicomplexa, like Monocystis sp., it is common parasitic annelids, such as worms. This organism is a correlate of pseudoparasitism in several animals but was not found to describe this product as an agent in nine banded armadillos, so this is a first description of Monocystis sp. in specimen of D. novemcinctus.(AU)

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The cholinergic anti-inflammatory pathway controls the inflammatory response and nonreflexive consciousness through bidirectional communication between the brain and immune system. Moreover, brain acetylcholinesterase activity may have a role in regulating the vagus nerve in this pathway. Thus, we analyzed the role of acetylcholine (ACh) in the inflammatory response 15 days after induction of sepsis by cecal ligation and puncture (CLP). Balb/c mice were pretreated with or without donepezil (5 mg/kg/day, orally) 7 days before CLP, and mice homozygous for vesicular ACh transporter (VAChT) knockdown (KD) were subjected to CLP. All animals were sacrificed 15 days after CLP, and the plasma, spleen, and hippocampus were collected. Characterization of splenic lymphocytes and cytokine levels in the plasma, spleen, and hippocampus was determined. Our results showed a splenomegaly in group CLP. The numbers of cytotoxic T cells, helper T cells, regulatory T cells, B cells, and Th17 cells differed between mice subjected to CLP and to sham operation in both untreated and donepezil-treated groups. In VAChT-KD mice, CLP resulted in decreased cytotoxic and helper T cells and increased in Th17 cells compared with the sham. Additionally, in VAChT-KD mice, the levels of pro-inflammatory cytokines, such as IL-1ß, IL-6, and TNF-α, were increased following CLP. Thus, we concluded that ACh affected the inflammatory response at 15 days after CLP since stimulation of cholinergic transmission increased the proliferation of lymphocytes, including regulatory T cells, in association with a lower inflammatory profile and VAChT-KD decreased the number of lymphocytes and increased inflammation.

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Evidence validating the influence of the cytochrome P450 (CYP) 2D6 and 2C19 enzymes genetic polymorphisms in the response to antipsychotics is scarce. We examined the hypothesis that a higher prevalence of CYP2D6 and/or CYP2C19 ultra rapid metabolizers might be found among refractory schizophrenia patients. Three groups were studied: refractory and non-refractory schizophrenia patients, and healthy controls. Participants were genotyped for CYP2D6 and CYP2C19 polymorphisms and classified in metabolic phenotypes. No between-group differences in the distribution of the phenotypes were found. Therefore, our findings do not support the CYPs 2D6 and 2C19 genotyping in the prediction of therapeutic response in schizophrenia.

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This study aimed to demonstrate that congenital diaphragmatic hernia (CDH) results in vascular abnormalities that are directly associated with the severity of pulmonary hypoplasia and hypertension. These events increase right ventricle (RV) afterload and may adversely affect disease management and patient survival. Our objective was to investigate cardiac function, specifically right ventricular changes, immediately after birth and relate them to myocardial histological findings in a CDH model. Pregnant New Zealand rabbits underwent the surgical procedure at 25 days of gestation (n=14). CDH was created in one fetus per horn (n=16), and the other fetuses were used as controls (n=20). At term (30 days), fetuses were removed, immediately dried and weighed before undergoing four-parameter echocardiography. The lungs and the heart were removed, weighed, and histologically analyzed. CDH animals had smaller total lung weight (P<0.005), left lung weight (P<0.005), and lung-to-body ratio (P<0.005). Echocardiography revealed a smaller left-to-right ventricle ratio (LV/RV, P<0.005) and larger diastolic right ventricle size (DRVS, P<0.007). Histologic analysis revealed a larger number of myocytes undergoing mitotic division (186 vs 132, P<0.05) in CDH hearts. Immediate RV dilation of CDH hearts is related to myocyte mitosis increase. This information may aid the design of future strategies to address pulmonary hypertension in CDH.

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This study aimed to demonstrate that congenital diaphragmatic hernia (CDH) results in vascular abnormalities that are directly associated with the severity of pulmonary hypoplasia and hypertension. These events increase right ventricle (RV) afterload and may adversely affect disease management and patient survival. Our objective was to investigate cardiac function, specifically right ventricular changes, immediately after birth and relate them to myocardial histological findings in a CDH model. Pregnant New Zealand rabbits underwent the surgical procedure at 25 days of gestation (n=14). CDH was created in one fetus per horn (n=16), and the other fetuses were used as controls (n=20). At term (30 days), fetuses were removed, immediately dried and weighed before undergoing four-parameter echocardiography. The lungs and the heart were removed, weighed, and histologically analyzed. CDH animals had smaller total lung weight (P<0.005), left lung weight (P<0.005), and lung-to-body ratio (P<0.005). Echocardiography revealed a smaller left-to-right ventricle ratio (LV/RV, P<0.005) and larger diastolic right ventricle size (DRVS, P<0.007). Histologic analysis revealed a larger number of myocytes undergoing mitotic division (186 vs 132, P<0.05) in CDH hearts. Immediate RV dilation of CDH hearts is related to myocyte mitosis increase. This information may aid the design of future strategies to address pulmonary hypertension in CDH.

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Extracellular matrix and costamere proteins transmit the concentric, isometric, and eccentric forces produced by active muscle contraction. The expression of these proteins after application of passive tension stimuli to muscle remains unknown. This study investigated the expression of laminin and dystrophin in the soleus muscle of rats immobilized with the right ankle in plantar flexion for 10 days and subsequent remobilization, either by isolated free movement in a cage or associated with passive stretching for up to 10 days. The intensity of the macrophage response was also evaluated. One hundred and twenty-eight female Wistar rats were divided into 8 groups: free for 10 days; immobilized for 10 days; immobilized/free for 1, 3, or 10 days; or immobilized/stretched/free for 1, 3, or 10 days. After the experimental procedures, muscle tissue was processed for immunofluorescence (dystrophin/laminin/CD68) and Western blot analysis (dystrophin/laminin). Immobilization increased the expression of dystrophin and laminin but did not alter the number of macrophages in the muscle. In the stretched muscle groups, there was an increase in dystrophin and the number of macrophages after 3 days compared with the other groups; dystrophin showed a discontinuous labeling pattern, and laminin was found in the intracellular space. The amount of laminin was increased in the muscles treated by immobilization followed by free movement for 10 days. In the initial stages of postimmobilization (1 and 3 days), an exacerbated macrophage response and an increase of dystrophin suggested that the therapeutic stretching technique induced additional stress in the muscle fibers and costameres.

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Extracellular matrix and costamere proteins transmit the concentric, isometric, and eccentric forces produced by active muscle contraction. The expression of these proteins after application of passive tension stimuli to muscle remains unknown. This study investigated the expression of laminin and dystrophin in the soleus muscle of rats immobilized with the right ankle in plantar flexion for 10 days and subsequent remobilization, either by isolated free movement in a cage or associated with passive stretching for up to 10 days. The intensity of the macrophage response was also evaluated. One hundred and twenty-eight female Wistar rats were divided into 8 groups: free for 10 days; immobilized for 10 days; immobilized/free for 1, 3, or 10 days; or immobilized/stretched/free for 1, 3, or 10 days. After the experimental procedures, muscle tissue was processed for immunofluorescence (dystrophin/laminin/CD68) and Western blot analysis (dystrophin/laminin). Immobilization increased the expression of dystrophin and laminin but did not alter the number of macrophages in the muscle. In the stretched muscle groups, there was an increase in dystrophin and the number of macrophages after 3 days compared with the other groups; dystrophin showed a discontinuous labeling pattern, and laminin was found in the intracellular space. The amount of laminin was increased in the muscles treated by immobilization followed by free movement for 10 days. In the initial stages of postimmobilization (1 and 3 days), an exacerbated macrophage response and an increase of dystrophin suggested that the therapeutic stretching technique induced additional stress in the muscle fibers and costameres.

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A single instillation of porcine pancreatic elastase (PPE) results in significant airspace enlargement on the 28th day after instillation, whereas cigarette smoke (CS) exposure requires 6 months to produce mild emphysema in rodents. Considering that there are differences in the pathogenesis of parenchymal destruction in these different experimental models, it is likely that there may be different patterns of extracellular matrix (ECM) remodeling. To evaluate ECM remodeling, C57BL/6 mice were submitted to either a nasal drop of PPE (PPE 28 Days) or exposed for 6 months to cigarette smoke (CS 6 months). Control groups received either an intranasal instillation of saline solution (Saline 28 Days) or remained without any smoke inhalation for six months (Control 6 months). We measured the mean linear intercept and the volume proportion of collagen type I, collagen type III, elastin and fibrillin. We used emission-scanning confocal microscopy to verify the fiber distribution. Both models induced increased mean linear intercept in relation to the respective controls, being larger in the elastase model in relation to the CS model. In the CS model, emphysema was associated with an increase in the volume proportion of fibrillin, whereas in the PPE model there was an increase in the parenchymal elastin content. In both models, there was an increase in collagen type III, which was higher in the CS-exposed mice. We concluded that ECM remodeling is different in the two most used experimental models of emphysema.

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BACKGROUND AND PURPOSE: Asthma is an inflammatory disease that involves airway hyperresponsiveness and remodelling. Flavonoids have been associated to anti-inflammatory and antioxidant activities and may represent a potential therapeutic treatment of asthma. Our aim was to evaluate the effects of the sakuranetin treatment in several aspects of experimental asthma model in mice. EXPERIMENTAL APPROACH: Male BALB/c mice received ovalbumin (i.p.) on days 0 and 14, and were challenged with aerolized ovalbumin 1% on days 24, 26 and 28. Ovalbumin-sensitized animals received vehicle (saline and dimethyl sulfoxide, DMSO), sakuranetin (20 mg kg(-1) per mice) or dexamethasone (5 mg kg(-1) per mice) daily beginning from 24th to 29th day. Control group received saline inhalation and nasal drop vehicle. On day 29, we determined the airway hyperresponsiveness, inflammation and remodelling as well as specific IgE antibody. RANTES, IL-5, IL-4, Eotaxin, IL-10, TNF-α, IFN-γ and GMC-SF content in lung homogenate was performed by Bioplex assay, and 8-isoprostane and NF-kB activations were visualized in inflammatory cells by immunohistochemistry. KEY RESULTS: We have demonstrated that sakuranetin treatment attenuated airway hyperresponsiveness, inflammation and remodelling; and these effects could be attributed to Th2 pro-inflammatory cytokines and oxidative stress reduction as well as control of NF-kB activation. CONCLUSIONS AND IMPLICATIONS: These results highlighted the importance of counteracting oxidative stress by flavonoids in this asthma model and suggest sakuranetin as a potential candidate for studies of treatment of asthma.

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Pulmonary remodeling is an important feature of asthma physiopathology that can contribute to irreversible changes in lung function. Although neurokinins influence lung inflammation, their exact role in the extracellular matrix (ECM) remodeling remains to be determined. Our objective was to investigate whether inactivation of capsaicin-sensitive nerves modulates pulmonary ECM remodeling in animals with chronic lung inflammation. After 14 days of capsaicin (50 mg/kg, sc) or vehicle administration, male Hartley guinea pigs weighing 250-300 g were submitted to seven inhalations of increasing doses of ovalbumin (1, 2.5, and 5 mg/mL) or saline for 4 weeks. Seventy-two hours after the seventh inhalation, animals were anesthetized and mechanically ventilated and the lung mechanics and collagen and elastic fiber content in the airways, vessels and lung parenchyma were evaluated. Ovalbumin-exposed animals presented increasing collagen and elastic fiber content, respectively, in the airways (9.2 ± 0.9; 13.8 ± 1.2), vessels (19.8 ± 0.8; 13.4 ± 0.5) and lung parenchyma (9.2 ± 0.9; 13.8 ± 1.2) compared to control (P < 0.05). Capsaicin treatment reduced collagen and elastic fibers, respectively, in airways (1.7 ± 1.1; 7.9 ± 1.5), vessels (2.8 ± 1.1; 4.4 ± 1.1) and lung tissue (2.8 ± 1.1; 4.4 ± 1.1) of ovalbumin-exposed animals (P < 0.05). These findings were positively correlated with lung mechanical responses to antigenic challenge (P < 0.05). In conclusion, inactivation of capsaicin-sensitive nerve fibers reduces pulmonary remodeling, particularly collagen and elastic fibers, which contributes to the attenuation of pulmonary functional parameters.

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Pulmonary remodeling is an important feature of asthma physiopathology that can contribute to irreversible changes in lung function. Although neurokinins influence lung inflammation, their exact role in the extracellular matrix (ECM) remodeling remains to be determined. Our objective was to investigate whether inactivation of capsaicin-sensitive nerves modulates pulmonary ECM remodeling in animals with chronic lung inflammation. After 14 days of capsaicin (50 mg/kg, sc) or vehicle administration, male Hartley guinea pigs weighing 250-300 g were submitted to seven inhalations of increasing doses of ovalbumin (1, 2.5, and 5 mg/mL) or saline for 4 weeks. Seventy-two hours after the seventh inhalation, animals were anesthetized and mechanically ventilated and the lung mechanics and collagen and elastic fiber content in the airways, vessels and lung parenchyma were evaluated. Ovalbumin-exposed animals presented increasing collagen and elastic fiber content, respectively, in the airways (9.2 ± 0.9; 13.8 ± 1.2), vessels (19.8 ± 0.8; 13.4 ± 0.5) and lung parenchyma (9.2 ± 0.9; 13.8 ± 1.2) compared to control (P < 0.05). Capsaicin treatment reduced collagen and elastic fibers, respectively, in airways (1.7 ± 1.1; 7.9 ± 1.5), vessels (2.8 ± 1.1; 4.4 ± 1.1) and lung tissue (2.8 ± 1.1; 4.4 ± 1.1) of ovalbumin-exposed animals (P < 0.05). These findings were positively correlated with lung mechanical responses to antigenic challenge (P < 0.05). In conclusion, inactivation of capsaicin-sensitive nerve fibers reduces pulmonary remodeling, particularly collagen and elastic fibers, which contributes to the attenuation of pulmonary functional parameters.

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Pneumonectomy is associated with high mortality and high rates of complications. Postpneumonectomy pulmonary edema is one of the leading causes of mortality. Little is known about its etiologic factors and its association with the inflammatory process. The purpose of the present study was to evaluate the role of pneumonectomy as a cause of pulmonary edema and its association with gas exchange, inflammation, nitric oxide synthase (NOS) expression and vasoconstriction. Forty-two non-specific pathogen-free Wistar rats were included in the study. Eleven animals died during or after the procedure, 21 were submitted to left pneumonectomy and 10 to sham operation. These animals were sacrificed after 48 or 72 h. Perivascular pulmonary edema was more intense in pneumonectomized rats at 72 h (P = 0.0131). Neutrophil density was lower after pneumonectomy in both groups (P = 0.0168). There was higher immunohistochemical expression of eNOS in the pneumonectomy group (P = 0.0208), but no statistically significant difference in the expression of iNOS. The lumen-wall ratio and pO2/FiO2 ratio did not differ between the operated and sham groups after pneumonectomy. Left pneumonectomy caused perivascular pulmonary edema with no elevation of immunohistochemical expression of iNOS or neutrophil density, suggesting the absence of correlation with the inflammatory process or oxidative stress. The increased expression of eNOS may suggest an intrinsic production of NO without signs of vascular reactivity.

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Pneumonectomy is associated with high mortality and high rates of complications. Postpneumonectomy pulmonary edema is one of the leading causes of mortality. Little is known about its etiologic factors and its association with the inflammatory process. The purpose of the present study was to evaluate the role of pneumonectomy as a cause of pulmonary edema and its association with gas exchange, inflammation, nitric oxide synthase (NOS) expression and vasoconstriction. Forty-two non-specific pathogen-free Wistar rats were included in the study. Eleven animals died during or after the procedure, 21 were submitted to left pneumonectomy and 10 to sham operation. These animals were sacrificed after 48 or 72 h. Perivascular pulmonary edema was more intense in pneumonectomized rats at 72 h (P = 0.0131). Neutrophil density was lower after pneumonectomy in both groups (P = 0.0168). There was higher immunohistochemical expression of eNOS in the pneumonectomy group (P = 0.0208), but no statistically significant difference in the expression of iNOS. The lumen-wall ratio and pO(2)/FiO(2) ratio did not differ between the operated and sham groups after pneumonectomy. Left pneumonectomy caused perivascular pulmonary edema with no elevation of immunohistochemical expression of iNOS or neutrophil density, suggesting the absence of correlation with the inflammatory process or oxidative stress. The increased expression of eNOS may suggest an intrinsic production of NO without signs of vascular reactivity.

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BACKGROUND: Leukotriene receptor antagonists have been demonstrated in several studies to possess bronchodilating and anti-inflammatory properties in asthma. However, there are few experimental studies performed to compare the effects of anti-leukotrienes and glucocorticoids, most used anti-inflammatory agents in asthma. In the present study, we evaluated the effects of treatment with dexamethasone or montelukast on eosinophil and mononuclear cell recruitment in an experimental model of allergen-induced chronic airway inflammation in guinea-pigs (GP). METHODS: GP were submitted to increasing concentrations of aerosols of ovalbumin (OVA) twice a week for 4 weeks. After 2 weeks, animals were treated daily with dexamethasone, montelukast or saline solution. After this period, GP were anaesthetized, tracheostomized, mechanically ventilated and challenged with OVA aerosol. RESULTS: Maximal changes of respiratory system resistance and elastance induced by OVA challenge were attenuated by dexamethasone (P<0.001), but not by montelukast treatment. Neither dexamethasone nor montelukast significantly influenced bronchial oedema formation. Dexamethasone but not montelukast induced a decrease in mononuclear cells in airways (P<0.001). Eosinophil infiltration in the bronchial wall was reduced by both dexamethasone and montelukast (P<0.005). Only dexamethasone treatment reduced the levels of exhaled nitric oxide (P<0.025). CONCLUSION: Although leukotriene receptor antagonist treatment reduces eosinophil accumulation induced by multiple antigen challenges, glucocorticoid treatment attenuates both eosinophil and mononuclear cell infiltration.

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