LUNGS HISTOLOGICAL CHANGES IN EXPERIMENTAL INTOXICATION WITH RELDAN 40 EC AT PELOPHYLAX RIDIBUNDUS (PALLAS, 1771)

The objective of this paper is to study the histological changes induced by Reldan 40EC in a dose of 0.01 ml chlorpyrifos/g body weight at the level of the lungs of the amphibian specimens Pelophylax ridibundus (Pallas, 1771). The insecticide was administrated by intraperitoneal injection (1 injection at 2 days in a scheme for 2 weeks). Highly degenerative changes were observed in animals cultured at 22–24°C, compared to those cultured at 4–6°C: thickness of alveolar septa, intraparietal, higher number of hypertrophied goblet cells, disorganization of blood capillaries, fibrosis.

Bronchopneumonia in sheep associated with Providencia stuartii

Bacteria of the genus Providencia are opportunistic pathogens in humans, widely distributed in the environment and associated with greater resistance to antibiotics, and this being uncommon the association with clinical diseases. This study reports the isolation of P. stuartii in two sheep that presented clinical signs of pneumonia. At necropsy there was severe and acute fibrinopurulent bronchopneumonia. Histologically, there were infiltrated neutrophils and fibrin in the alveolar lumen, and the alveolar septa presented multifocal thickening with moderate proliferation of pneumocytes and mononuclear interstitial infiltrate. Providencia sp. was isolated in the microbiological tests of the lung and tracheal secretions. The isolate was subjected to DNA extraction, polymerase chain reaction (PCR) for the 16SrRNA gene and sequencing of genomic DNA, which demonstrated 100% homology with P. stuartii. This is the first report of the presence of this microorganism as a cause of interstitial and fibrinopurulent bronchopneumonia in sheep. Therefore, it is suggested that epidemiological surveillance strategies should be carried out in animals to better understand their role in the dissemination of this pathogen.

The Heterogeneity of Inflammatory Response and Emphysema in Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD) is a heterogeneous disease characterized by chronic inflammation, emphysema, airway remodeling, and altered lung function. Despite the canonical classification of COPD as a neutrophilic disease, blood and airway eosinophilia are found in COPD patients. Identifying the tools to assess eosinophilic airway inflammation in COPD models during stable disease and exacerbations will enable the development of novel anti-eosinophilic treatments. We developed different animal models to mimic the pathological features of COPD. Our results show that eosinophils accumulated in the lungs of pancreatic porcine elastase-treated mice, with emphysema arising from the alveolar septa. A lipopolysaccharide challenge significantly increased IL-17 levels and induced a swift change from a type-2 response to an IL-17-driven inflammatory response. However, lipopolysaccharides can exacerbate cigarette smoking-induced airway inflammation dominated by neutrophil infiltration and airway remodeling in COPD models. Our results suggest that eosinophils may be associated with emphysema arising from the alveolar septa, which may be different from the small airway disease-associated emphysema that is dominated by neutrophilic inflammation in cigarette smoke-induced models. The characterization of heterogeneity seen in the COPD-associated inflammatory signature could pave the way for personalized medicine to identify new and effective therapeutic approaches for COPD.

Hyperoxia-Exposed Lung Injury Upregulates DVL-1 Protein Expression And Activates Wnt/β-Catenin Signaling Pathway in Newborn Rat Lung

Background: Bronchopulmonary dysplasia (BPD) is a serious and lifelong pulmonary disease in premature neonates, which has an influence on a quarter of premature newborns. Wingless/integrated(Wnt)/β-catenin signaling pathway affects lung cell differentiation and lung tissue structure, and is abnormal activation in the lungs of rats with pulmonary fibrosis. Method: Newborn rats were subjected to hyperoxia-exposure, histopathological changes in lung tissues were evaluated through Immunohistochemistry (IHC), Dishevelled (DVL-1) and signaling pathways were detected through western blotting and real-time PCR. Results: Contrasting with the normoxic lungs, hyperoxia-exposed lungs demonstrated larger alveoli, less alveoli and thicker alveolar septa, and the number of alveoli reduced obviously, alveoli enlarged seriously in hyperoxia group. SOD activity was decreased (7 th day: P < 0.05; 14 th day: P < 0.01), and MDA was increased (7 th day: P < 0.05; 14 th day: P < 0.01) after hyperoxia exposure. Protein and mRNA expression levels of β-catenin, DVL-1, Ctnnbl1 and Cyclin D1 were upregulated by hyperoxia exposure on 7 th day( P < 0.01) and 14 th day( P < 0.01). Conclusion: We confirmed the positive role of DVL-1 and Wnt/β-catenin signaling pathway in promoting BPD under hyperoxia conditions, and provided promising therapeutic targets in the future.

Inhalation of helium in plastic bag suffocation with suicidal purpose: Observation and differences of two cases

The use of helium in plastic bag suffocation is a suicide method recently found in forensic cases. Although it is not common practice, there has been a strong increase in its use during the past 20 years, thanks to the accessibility of information on the web and materials needed to implement it. From a pathophysiological point of view, there are various theories on how helium can change the timing and, also, the cause of death when the head is inside a plastic bag. We report two cases where we believe that the action of helium, whose unequivocal use is demonstrated by the circumstantial data, has unfolded in a different way. In the first case, the discovery of an intense cyanosis of the face, blood leakage from the respiratory orifices and the destruction of numerous alveolar septa with histologically demonstrated blood extravasation, was left for a longer agonic period and a no negligible rate of pulmonary barotrauma in determination of death. In the second case, the total absence of external pathological phenomena, internal and histological, allows us to hypothesise an onset of death that is faster and catalysed by helium and explained by the known sympathetic hyperactivation and consequent cardiac arrhythmic death described in similar plastic bag suffocation cases.

Research article expression of surfactant protein-A and D, and CD9 in lungs of 1 and 30 day old foals

Background Respiratory diseases are a major cause of morbidity and mortality in the horses of all ages including foals. There is limited understanding of the expression of immune molecules such as tetraspanins and surfactant proteins (SP) and the regulation of the immune responses in the lungs of the foals. Therefore, the expression of CD9, SP-A and SP-D in foal lungs was examined. Results Lungs from one day old (n = 6) and 30 days old (n = 5) foals were examined for the expression of CD9, SP-A, and SP-D with immunohistology and Western blots. Western blot data showed significant increase in the amount of CD9 protein (p = 0.0397) but not of SP-A and SP-D at 30 days of age compared to one day. Immunohistology detected CD9 in the alveolar septa and vascular endothelium but not the bronchiolar epithelium in the lungs of the foals in both age groups. SP-A and SP-D expression was localized throughout the alveolar septa including type II alveolar epithelial cells and the vascular endothelium of the lungs in all the foals. Compared to one day old foals, the expression of SP-A and SP-D appeared to be increased in the bronchiolar epithelium of 30 day old foals. Pulmonary intravascular macrophages were also positive for SP-A and SP-D in 30 days old foals and these cells are not developed in the day old foals. Conclusions This is the first data on the expression of CD9, SP-A and SP-D in the lungs of foals.

POS0334 INTERSTITIAL LUNG INFLAMMATION WITH ALVEOLAR HEMORRHAGE IN AUTOIMMUNE MRL/MP-LPR/LPR MICE

Background:Anti-melanoma differentiation-associated gene 5 (MDA5) antibody is associated with interstitial lung disease (ILD) in patients with juvenile dermatomyositis (JDM). Although the mechanisms leading to pulmonary involvements remain uncertain, both inflammatory cytokines and autoimmune response between MDA5 and anti-MDA5 antibody could been inferred. The present study examined the roles of MDA5 in an inducible form of lung involvement that develops in autoimmune mice treated with the pristane.Objectives:MRL/Mp-lpr/lpr mice and wild type controls (+/+) at 5 weeks of age. They received 0.5ml of pristane or an equal volume of PBS IP at the age 7 week (day 1). And 1.2μg of recombinant human MDA5 protein (rMDA5) was instilled IP or PBS at day2 and Day9. The mice were sacrificed on 8 weeks after the intraperitoneal injection. Lung tissue was harvested for histological assessment.Methods:MRL/Mp-lpr/lpr mice and wild type controls (+/+) at 5 weeks of age. They received 0.5ml of pristane or an equal volume of PBS IP at the age 7 week (day 1). And 1.2μg of recombinant human MDA5 protein (rMDA5) was instilled IP or PBS at day2 and Day9. The mice were sacrificed on 8 weeks after the intraperitoneal injection. Lung tissue was harvested for histological assessment.Results:Lung involvements did not develop in PBS-treated MRL/lpr mice and WT mice. And Lung involvements did not develop in rMDA5 protein-treated WT mice. H&E staining of lung tissue from MRL/lpr mice and WT mouse with pristane that showed induced bland alveolar hemorrhage. H&E staining of lung from WT mouse compared with lung from a MRL/lpr mouse treated with pristane + rMDA5 protein showing mild thickening of the alveolar septa despite the alveolar hemorrhage. And perivascular lymphocytes infiltrate in a MRL/lpr mouse rather than a WT mouse treated with pristane + rMDA5 protein. CD163 staining of alveolar macrophages were present in the alveolar spaces was more intense in mouse treated with pristane + rMDA5 protein than in mouuse treated with only pristane. The Lymphocyte infiltrations around alveolar macrophages was more prominent in MRL/lpr mouse treated with pristane + rMDA5 protein than other mouse.Conclusion:These results suggest that lung involvements such as the alveolar hemorrhage, are caused by pristeine and rMDA5 prtotein in the pathogenesis of interstitial pneumonia. MRL/lpr mouse treated with pristane + rMDA5 protein showed more alveolar macrophages that had lymphocyte infiltrations. After the alveolar hemorrhage by pritane, the antigen exposure of MDA5 might induce continuously inflammatory response to lymphocytes and macrophages in the alveolar lesions.References:[1]Sunderrajan VE, McKenzie NW, Lieske RT, et al. Pulmonary inflammation in autoimmune MRL/Mp-lpr/lpr mice. Histopathology and bronchoalveolar lavage evaluation. Am J Pathol. 1986;124: 353–362.[2]Tolga Barker T, Lee YP, Scumpia KK, et al. Pathogenic role of B-cells in the development of diffuse alveolar hemorrhage induced by pristane. Lab Invest. 2011; 91: 1540–1550.Figure 1.Lung disease (A-D). Light microscopy. Lung tissue from mice 8 weeks after treatment were stained with H&E. (A) Pristeine -treated WT mice with almost no alveolar lesions. (B) Pristane + rMDA5 protein -treated WT mice with alveolar hemorrhage and slight lymphocyte infiltrations. (C) Pristeine -treated MRL/lpr mouse with almost no alveolar lesions and slight lymphocyte infiltrations. (D) Pristeine -treated MRL/lpr mouse with alveolar hemorrhage and lymphocyte infiltrations, thickening of the alveolar septa.Disclosure of Interests:None declared

Rescuable effect of R-salbutamol in LPS-induced immune dysfunction of sepsis

Sepsis is a severe life-threatening condition caused by a dysregulated host response to infection. So far, there are no pharmacotherapies to stop sepsis. Salbutamol, an commonly used β2-adrenoreceptor agonist, has found to be potential in regulating immune response dysfunction and exert anti-inflammatory effect. However, salbutamol exists two isomers. R-isomer exhibits the therapeutic effect and clinical benefit, while S-isomer proves to be detrimental rather than benign. So, in this study, we investigated the preventive and therapeutic effect of R-salbutamol (R-sal), S-salbutamol (S-sal) or racemic mixture in a mouse model of lipopolysaccharide (LPS)-induced sepsis. Dexamethasone (Dex) was set as comparison. The results showed that R-sal markedly improved seven-day survival rate of septic mice both administered before or after LPS. Whereas Dex showed toxic and accelerated the death of septic mice when given before LPS injection. Lung histological examination and lung function assay revealed that LPS challenge resulted in acute lung damage, including inflammatory cell infiltration, thickened alveolar septa and congestion, and decreased minute volume in septic mice. R-sal pretreatment efficiently inhibited these changes, accompanying by markedly reduced lung MPO level, serum cytokines levels and lactate release and significantly restored the lymphocytes and suppressed the percentage of monocytes. Racemic mixture exhibited diminished effects while S-sal showed enhanced cytokines release. In addition, R-sal pretreatment showed a better improvement in prognostic pulmonary function at day4 in survived mice than that of Rac-sal. Collectively, our results indicate the potential benefit of R-sal for sepsis and sepsis-induced lung injury.

Ghrelin Expression in Mast Cells of Infant Lung with Respiratory Distress Syndrome

This article sheds light on some features of ghrelin (GHR)- and tryptase (Try)-positive mast cells (MCs) distribution in human lung of preterm newborns with respiratory distress syndrome (RDS). GHR possessed anti-inflammatory activity and reliable therapeutic properties in some lung diseases. So far, GHR expression has been defined predominantly in neuroendocrine cells of bronchial mucosa in fetal and infant lungs. Lung tissue from 8 dead newborns with RDS were investigated immunohistochemically with anti-GHR and anti-Try antibodies. The number of GHR+ and Try+ MCs was determined in three locations –bronchi, bronchiole and in alveolar septa. MCs were more numerous around main bronchi with diminishing numbers around bronchiole and in alveolar septa. The number of MCs in the latter was increased in newborns with pneumonia. The number of GHR+ MCs in alveolar septa was lower in newborns with RDS as compared to newborns with RDS combined with pneumonia (2.83 ± 1.13 vs 4.81 ± 2.6, p < 0.001). The amount of Try+ MCs along bronchial wall was significantly more than GHR+ MCs in RDS newborns (6.97 ± 4.53 vs 3.85 ± 4.30, p = 0.001). It could be supposed that pulmonary MCs increased in newborn lungs in inflammatory process. MCs in human lung contained GHR peptide that had immunomodulatory function and participated in hormone regulation of inflammation.

Lack of CD34 delays bacterial endotoxin-induced lung inflammation

Background CD34, a pan-selectin binding protein when glycosylated, has been shown to be involved in leukocyte migration to the site of inflammation. However, only one report is available on the expression and role of CD34 in neutrophil recruitment during acute lung inflammation. Methods We proceeded to study the role of CD34 in lung neutrophil migration using mouse model of endotoxin induced acute lung inflammation and studied over multiple time points, in generic CD34 knock-out (KO) strain. Results While there was no difference in BAL total or differential leukocyte counts, lung MPO content was lower in LPS exposed KO compared to WT group at 3 h time-point (p = 0.0308). The MPO levels in CD34 KO mice begin to rise at 9 h (p = 0.0021), as opposed to an early 3 h rise in WT mice (p = 0.0001), indicating that KO mice display delays in lung neutrophil recruitment kinetics. KO mice do not loose endotoxin induced lung vascular barrier properties as suggested by lower BAL total protein at 3 h (p = 0.0452) and 24 h (p = 0.0113) time-points. Several pro-inflammatory cytokines and chemokines (TNF-α, IL-1β, KC, MIP-1α, IL-6, IL-10 and IL-12 p70 sub-unit; p < 0.05) had higher levels in WT compared to KO group, at 3 h. Lung immunofluorescence in healthy WT mice reveals CD34 expression in the bronchiolar epithelium, in addition to alveolar septa. Conclusion Thus, given CD34′s pan-selectin affinity, and expression in the bronchiolar epithelium as well as alveolar septa, our study points towards a role of CD34 in lung neutrophil recruitment but not alveolar migration, cytokine expression and lung inflammation.