Identification and validation of candidate genes dysregulated in alveolar macrophages of acute respiratory distress syndrome.

BACKGROUND: Acute respiratory distress syndrome (ARDS) is a common cause of death in ICU patients and its underlying mechanism remains unclear, which leads to its high mortality rate. This study aimed to identify candidate genes potentially implicating in the pathogenesis of ARDS and provide novel therapeutic targets. METHODS: Using bioinformatics tools, we searched for differentially expressed genes (DEGs) in an ARDS microarray dataset downloaded from the Gene Expression Omnibus (GEO) database. Afterwards, functional enrichment analysis of GO, KEGG, GSEA and WGCNA were carried out to investigate the potential involvement of these DEGs. Moreover, the Protein-protein interaction (PPI) network was constructed and molecular complexes and hub genes were identified, followed by prognosis analysis of the hub genes. Further, we performed qRT-PCR, Western Blot and flow cytometry analysis to detect candidate genes of CCR2 and FPR3 in macrophage model of LPS-induced ARDS and primary alveolar macrophages(AMs). Macrophage chemotaxis was evaluated using Transwell assay. RESULTS: DEGs mainly involved in myeloid leukocyte activation, cell chemotaxis, adenylate cyclase-modulating G protein-coupled receptor signaling pathway and cytokine-cytokine receptor interaction. Basing on the constructed PPI network, we identified five molecular complexes and 10 hub genes potentially participating in the pathogenesis of ARDS. It was observed that candidate genes of CCR2 and FPR3 were significantly over-expressed in primary alveolar macrophages from ARDS patients and macrophgae model of LPS-induced ARDS. Moreover, in vitro transwell assay demonstrated that CCR2 and FPR3 down-regulation, respectively, inhibited LPS-triggered macrophage chemotaxis toward CCL2. Finally, a positive correlation between FPR3 and CCR2 expression was confirmed using pearson correlation analysis and Western Blot assay. CONCLUSIONS: Our study identified CCR2 and FPR3 as the candidate genes which can promote macrophage chemotaxis through a possible interaction between FPR3 and CCL2/CCR2 axis and provided novel insights into ARDS pathogenesis.

Evaluation for effects of severe acidosis on hemostasis in trauma patients using thrombelastography analyzer.

OBJECTIVE: To investigate effects of metabolic acidosis on hemostasis function in trauma patients using thromboelastography analyzer. METHODS: 65 critically injured patients and 19 healthy volunteers were enrolled in the study. Three samples of whole blood were collected from each patient or healthy volunteer. These three samples were acidified with 50mmol/l phosphate-buffered saline (PBS) (pH5.8) or a neutral buffer (50mmol/l phosphate, pH7.4) and acidified blood sample with target pH of 6.95, 7.15 or 7.35 was obtained respectively. These three samples with target pH value were added into thrombelastography analyzer (TEG® 5000 Thrombelastograph Hemostasis Analyzers; Haemoscope Corporation, Niles, Illinois, USA) respectively and variables of Clot time (r), Rate of clot formation (α Angle), Clot formation time (K), Coagulation Index (CI) and Maximum strength (MA) were monitored at 37°C. Besides, association between TEG® parameters and clinicopathological features was analyzed by the Pearson χ2 test. RESULTS: In trauma patients, all 5 thrombelastographic variables, Clot time (r), Clot formation time (K), Maximum Amplitude (MA), Rate of clot formation (α Angle) and Coagulation Index (CI), were significantly affected by blood acidification, F(1.321,83.213)=88.960, P<0.001, F(2,128)=112.738, P<0.001, F(1.199,76.748)=37.964, P<0.001, F(1.195,76.452)=16.789, P<0.001 and F(2,128)=178.674, P<0.001. Post hoc tests showed that moderate acidosis (pH7.15) significantly elongated K time (from 2.6 to 3.4min, P=0.0013) and increased α Angle (from 51.9°to 52.2°, P=0.0040). r, MA and CI were not markedly influenced under moderate acidification. Comparing to mild acidosis (pH7.15), severe acidosis (pH6.95) induced more serious impairment to hemostasis and all 5 variables was substantially affected, r (from 5.9 to 6.8min, P<0.001), K (from 3.4 to 3.9min, P<0.001), α Angle (from 52.2°to 50.8°, P=0.002), MA (from 52.9 to 51.6mm, P<0.001) and CI (from -2.3 to -4.2, P<0.001). Additionally, higher r elongation under severe acidosis was significantly associated with an increased mortality rate and transfusion requirement (P=0.019 and 0.031). In healthy volunteers, similar effects on hemostasis were detected. Inhibition ratios of thrombelastographic parameters were significantly higher in trauma patients than in healthy volunteers indicating severer impairment of metabolic acidosis to hemostasis in critically injured patients. CONCLUSIONS: The degree of metabolic acidosis in trauma patients is positively correlated to the severity of hemostasis dysfunction. Additionally, acidosis induces more serious impairment to hemostasis in trauma patients than in healthy volunteers. Moreover, acidosis-induced r time elongation is positively related to a higher death rate and increased transfusion requirement and this indicates a predictive role of TEG® variables for prognosis of traumatized patients.

Protective effect of hydrogen-saturated saline on acute lung injury induced by oleic acid in rats.

BACKGROUND: The purpose of the study is to investigate the role and mechanisms of hydrogen-saturated saline (HSS) in the acute lung injury (ALI) induced by oleic acid (OA) in rats. METHODS: Rats were treated with OA (0.1 mL/kg) to induce ALI and then administered with HSS (5 mL/kg) by intravenous (iv) and intraperitoneal (ip) injection, respectively. Three hours after the injection with OA, the arterial oxygen partial pressure (PaO2), arterial oxygen saturation (SaO2), carbon dioxide partial pressure (PaCO2), and bicarbonate (HCO3-) levels were analyzed using blood gas analyzer. In addition, the levels of malondialdehyde (MDA), tumor necrosis factor-α (TNF-α), and interleukin 1ß (IL-1ß) and myeloperoxidase (MPO) activity were measured by commercial kits, and pathological changes of lung tissue were examined by HE staining. Finally, the correlations of MPO activity or MDA level with the levels of TNF-α or IL-1ß were analyzed by Pearson's correlation analysis. RESULTS: We found decreased PaO2 levels and the pathological changes of lung tissue of ALI after OA injection. In addition, OA increased the levels of MDA, TNF-α, and IL-1ß, as well as MPO activity in lung tissues (P < 0.05). However, after treatment with HSS, all of these changes were alleviated (P < 0.05), and these changes were mitigated when treated with HSS by ip then iv injection (P < 0.05). Furthermore, MDA level and MPO activity were positively correlated with TNF-α and IL-1ß levels in the lung tissue, respectively (P < 0.01). CONCLUSION: HSS attenuated ALI induced by OA in rats and might protect against ALI through selective resistance to oxidation and inhibiting inflammatory infiltration.

Association of apneic oxygenation with decreased desaturation rates during rapid sequence intubation by a Chinese emergency medicine service.

Rapid and safe airway management has always been of paramount importance in successful management of critically ill and injured patients in the emergency department. The achievement rate of emergency medicine inhabitants in airway management improved enhanced essentially subsequent to finishing anaesthesiology turn. There was a slightly higher rate of quick sequence intubation in the postapneic oxygenation groups (preapneic oxygenation 6.4%; postapneic oxygenation 9.1%). The majority of patients intubated in both groups were men (preapneic oxygenation 72.3%; postapneic oxygenation 63.5%). A higher percentage of patients in the preapneic oxygenation group had a Cormack-Lehane grade III or worse view (23.2% versus 11.8%). Anaesthesiology turns should be considered as an essential component of emergency medicine training programs. A collateral curriculum of this nature should also focus on the acquisition of skills in airway management.