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Background

Lung ultrasound can accelerate the diagnosis of life-threatening diseases in adults with respiratory symptoms.

Objective

Systematically review the accuracy of lung ultrasonography (LUS) for emergency diagnosis of pneumonia, acute heart failure, and exacerbation of chronic obstructive pulmonary disease (COPD)/asthma in adults.

Methods

PubMed, Embase, Scopus, Web of Science, and LILACS (Literatura Latino Americana e do Caribe em Ciências da Saúde; until 2016) were searched for prospective diagnostic accuracy studies. Rutter-Gatsonis hierarchical summary receiver operating characteristic method was used to measure the overall accuracy of LUS and Reitsma bivariate model to measure the accuracy of the different sonographic signs. This review was previously registered in PROSPERO (Centre for Reviews and Dissemination, University of York, York, UK; CRD42016048085).

Results

Twenty-five studies were included: 14 assessing pneumonia, 14 assessing acute heart failure, and four assessing exacerbations of COPD/asthma. The area under the summary receiver operating characteristic curve of LUS was 0.948 for pneumonia, 0.914 for acute heart failure, and 0.906 for exacerbations of COPD/asthma. In patients suspected to have pneumonia, consolidation had sensitivity of 0.82 (95% confidence interval [CI] 0.74–0.88) and specificity of 0.94 (95% CI 0.85–0.98) for this disease. In acutely dyspneic patients, modified diffuse interstitial syndrome had sensitivity of 0.90 (95% CI 0.87–0.93) and specificity of 0.93 (95% CI 0.91–0.95) for acute heart failure, whereas B-profile had sensitivity of 0.93 (95% CI 0.72–0.98) and specificity of 0.92 (95% CI 0.79–0.97) for this disease in patients with respiratory failure. In patients with acute dyspnea or respiratory failure, the A-profile without PLAPS (posterior-lateral alveolar pleural syndrome) had sensitivity of 0.78 (95% CI 0.67–0.86) and specificity of 0.94 (95% CI 0.89–0.97) for exacerbations of COPD/asthma.

Conclusion

Lung ultrasound is an accurate tool for the emergency diagnosis of pneumonia, acute heart failure, and exacerbations of COPD/asthma.  相似文献   
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ObjectivesSome pro-inflammatory lipids derived from 1 lipooxygenase enzyme are potent neutrophil chemoattractant, a cell centrally involved in acute respiratory distress syndrome (ARDS); a syndrome lacking effective treatment. Considering the beneficial effects of the leukotriene receptor inhibitor, montelukast, on other lung diseases, whether montelukast attenuates inflammation in a mouse model of ARDS, and whether it reduces LPS stimulated activation of human neutrophils was investigated.MethodsThirty-five C57Bl/6 mice were distributed into control (PBS) + 24 h, LPS + 24 h (10 μg/mouse), control + 48 h, LPS + 48 h, and LPS 48 h + Montelukast (10 mg/kg). In addition, human neutrophils were incubated with LPS (1 μg/mL) and treated with montelukast (10 μM).ResultsOral-tracheal administration of montelukast significantly attenuated total cells (P < .05), macrophages (P < .05), neutrophils (P < .01), lymphocytes (P < .001) and total protein levels in BAL (P < .05), as well as IL-6 (P < .05), CXCL1/KC (P < .05), IL-17 (P < .05) and TNF-α (P < .05). Furthermore, montelukast reduced neutrophils (P < .001), lymphocytes (P < .01) and macrophages (P < .01) in the lung parenchyma. In addition, montelukast restored BAL VEGF levels (P < .05). LTB4 receptor expression (P < .001) as well as NF-κB (P < .001), a downstream target of LPS, were also reduced in lung parenchymal leukocytes. Furthermore, montelukast reduced IL-8 (P < .001) production by LPS-treated human neutrophils.ConclusionIn conclusion, montelukast efficiently attenuated both LPS-induced lung inflammation in a mouse model of ARDS and in LPS challenged human neutrophils.  相似文献   
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The metabolic syndrome includes changes in blood glucose levels, arterial hypertension, triglycerides, dyslipidemia and central obesity. Countless reports have described the correlation between the metabolic syndrome and cognitive impairment. However, only a few reports have assessed cognitive impairment associated with the metabolic syndrome in animals of both sexes. For this purpose, Sprague‐Dawley male and female rats were fed either with a hypercaloric diet as model of the metabolic syndrome or with a standard chow diet as controls. Subsequently, spatial learning and memory (Morris water maze) as well as short‐ and long‐term memory (passive avoidance task) were evaluated. Body weight, blood pressure, triglycerides, and total cholesterol significantly increased (F(1, 36) = 94.89, p < .001) in rats fed with hypercaloric diet compared to control rats. Furthermore, cognitive impairment was observed in spatial learning and spatial memory on male rats but not on female rats fed with hypercaloric diet. In addition, a long‐term memory impairment was observed in both groups fed with hypercaloric diet in comparison to their respective control group (F(1, 32) = 10.61, p = .0027). Immunohistochemistry results showed no changes in the number of positive cells for NeuN, GFAP and Ox‐42. In males fed with a hypercaloric diet, a decrease in testosterone levels was observed, whereas estradiol levels decreased in females when compared with their respective control group (p < .0001). In this MetS animal model, metabolic and cognitive differences were observed in males and females, which demonstrates that sex hormones play a significant role in metabolic regulation and neuroprotection related to the CA1 region of the hippocampus.  相似文献   
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CB2 receptors (CB2R) are expressed in midbrain neurons. To evidence the control of dopamine release in dorsal striatum by CB2R, we performed experiments of [3H]-dopamine release in dorsal striatal slices. We found a paradoxical increase in K+-induced [3H]-dopamine release by CB2R activation with GW 833972A and JWH 133 two selective agonist. To understand the mechanism involved, we tested for a role of the D2 autoreceptor in this effect; because in pallidal structures, the inhibitory effect of CB1 receptors (CB1R) on GABA release is switched to a stimulatory effect by D2 receptors (D2R). We found that the blockade of D2 autoreceptors with sulpiride prevented the stimulatory effect of CB2R activation; in fact, under this condition, CB2R decreased dopamine release, indicating the role of the D2 autoreceptor in the paradoxical increase. We also found that the effect occurs in nigrostriatal terminals, since lesions with 6-OH dopamine in the middle forebrain bundle prevented CB2R effects on release. In addition, D2–CB2R interaction promoted cAMP accumulation, and the increase in [3H]-dopamine release was prevented by PKA blockade. D2–CB2R coprecipitation and proximity ligation assay studies indicated a close interaction of receptors that could participate in the observed effects. Finally, intrastriatal injection of CB2R agonist induced contralateral turning in amphetamine-treated rats, which was prevented by sulpiride, indicating the role of the interaction in motor behavior. Thus, these data indicate that the D2 autoreceptor switches, from inhibitory to stimulatory, the CB2R effects on dopamine release, involving the cAMP → PKA pathway in nigrostriatal terminals.  相似文献   
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Journal of Neurology - Trans-active response DNA-binding protein of 43&nbsp;kDa (TDP-43) can be detected in up to 63% of autopsy-confirmed Lewy body disease (LBD) cases. It is unclear whether...  相似文献   
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