Prognostic value of secretory autophagosomes in patients with acute respiratory distress syndrome.

BACKGROUND: Growing evidence supports that extracellular vesicles (EVs) in blood plasma and other body fluids may function as biomarkers for disease. We previously found that secretory autophagosomes (SAPs), a kind of EV, could exacerbate lung injury in mice. However, the clinical value of SAPs in acute respiratory distress syndrome (ARDS), the most severe form of lung injury, remains unknown. Our study investigated the prognostic value of secretory autophagosomes in ARDS. METHODS: ARDS patients (n = 46) and controls (n = 8) were included in a prospective monocentric study. Bronchoalveolar lavage fluid (BALF) samples were collected from ARDS patients on the first day (Day 1) or the third day (Day 3) of enrollment and were collected from controls on Day 1. Gradient centrifugation was performed to isolate EVs. The size and concentration of EVs were characterized by nanoparticle tracking analysis (NTA). SAPs in EVs were characterized by flow cytometry, transmission electron microscopy, and western blot analysis, and the proportion of SAPs in EVs (PSV) was measured by flow cytometry. The association of SAPs with 28-day mortality was assessed. RESULTS: On Days 1 and 3, the proportion of SAPs (SAPs%) in BALF was higher in patients with ARDS than in controls. On Day 3, the SAPs% was significantly higher in nonsurvivors than in survivors. In particular, a high SAPs% was associated with poor overall survival in ARDS patients. Furthermore, the combination of SAPs% and SOFA obtained a higher predictive value of ARDS outcome than PSV or SOFA alone. CONCLUSION: SAPs% in BALF is elevated in patients with ARDS and is associated with the risk of death in ARDS, suggesting that SAPs% may be a novel prognostic biomarker in ARDS.

Cardiac performance and heart gene network provide dynamic responses of bay scallop Argopecten irradians irradians exposure to marine heatwaves.

The increased frequency of marine heat waves (MHWs) caused by global climate change is predicted to threaten the survival of economic bivalves, therefore having severely adverse effects on local ecological communities and aquaculture production. However, the study of scallops facing MHWs is still scarce, particularly in the scallop Argopecten irradians irradians, which has a significant share of "blue foods" in northern China. In the present study, bay scallop heart was selected to detect its cardiac performance, oxidative impairment and dynamic molecular responses, accompanied by assessing survival variations of individuals in the simulated scenario of MWHs (32 °C) with different time points (0 h, 6 h, 12 h, 24 h, 3 d, 6 d and 10 d). Notably, cardiac indices heart rate (HR), heart amplitude (HA), rate-amplitude product (RAP) and antioxidant enzyme activities superoxide dismutase (SOD) and catalase (CAT) all peaked at 24 h but sharply dropped on 3 d, coinciding with mortality. Transcriptome analysis revealed that the heart actively defended against heat stress at the acute stage (<24 h) via energy supply, misfolded proteins correction and enhanced signal transduction, whereas regulation of the defense response and apoptotic process combined with twice transcription initiation were the dominant responses at the chronic stage (3-10 d). In particular, HSP70 (heat shock protein 70), HSP90 and CALR (calreticulin) in the endoplasmic reticulum were identified as the hub genes (top 5 %) in the HR-associated module via WGCNA (weighted gene co-expression network analysis) trait-module analysis, followed by characterization of their family members and diverse expression patterns under heat exposure. Furthermore, RNAi-mediated knockdown of CALR expression (after 24 h) significantly weakened the thermotolerance of scallops, as evidenced by a drop of 1.31 °C in ABT (Arrhenius break temperature) between the siRNA-injected group and the control group. Our findings elucidated the dynamic molecular responses at the transcriptome level and verified the cardiac functions of CALR in bay scallops confronted with stimulated MHWs.

MiR-199a-3p-regulated alveolar macrophage-derived secretory autophagosomes exacerbate lipopolysaccharide-induced acute respiratory distress syndrome.

Purpose: Acute respiratory distress syndrome (ARDS) is a prevalent illness in intensive care units. Extracellular vesicles and particles released from activated alveolar macrophages (AMs) assist in ARDS lung injury and the inflammatory process through mechanisms that are unclear. This study investigated the role of AM-derived secretory autophagosomes (SAPs) in lung injury and microRNA (MiR)-199a-3p-regulated inflammation associated with ARDS in vitro and in a murine model. Methods: The ARDS model in mouse was established by intratracheal LPS lipopolysaccharide (LPS) injection. The agomirs or antagomirs of MiR-199a-3p were injected into the caudal vein to figure out whether MiR-199a-3p could influence ARDS inflammation and lung injury, whereas the mimics or inhibitors of MiR-199a-3p, siRNA of Rab8a, or PAK4 inhibitor were transfected or applied to RAW264.7 cells to evaluate the mechanism of SAP release. Culture supernatants of RAW264.7 cells treated with LPS or bronchoalveolar lavage fluid from mice were collected for the isolation of SAPs. Results: We found that MiR-199a-3p was over-expressed in the lungs of ARDS mice. The MiR-199a-3p antagomir alleviated, whereas the MiR-199a-3p agomir exacerbated LPS-induced inflammation in mice by promoting AM-derived SAP secretion. In addition, MiR-199a-3p over-expression exacerbated LPS-induced ARDS via activating Rab8a, and Rab8a silencing significantly suppressed the promoting influence of the MiR-199a-3p mimic on SAP secretion. Furthermore, MiR-199a-3p mimic activated Rab8a by directly inhibiting PAK4 expression. Conclusion: The novel finding of this study is that MiR-199a-3p participated in the regulation of SAP secretion and the inflammatory process via targeting of PAK4/Rab8a, and is a potential therapeutic candidate for ARDS treatment.

Tissue-Specific and Time-Dependent Expressions of PC4s in Bay Scallop (Argopecten irradians irradians) Reveal Function Allocation in Thermal Response.

Transcriptional coactivator p15 (PC4) encodes a structurally conserved but functionally diverse protein that plays crucial roles in RNAP-II-mediated transcription, DNA replication and damage repair. Although structures and functions of PC4 have been reported in most vertebrates and some invertebrates, the PC4 genes were less systematically identified and characterized in the bay scallop Argopecten irradians irradians. In this study, five PC4 genes (AiPC4s) were successfully identified in bay scallops via whole-genome scanning through in silico analysis. Protein structure and phylogenetic analyses of AiPC4s were conducted to determine the identities and evolutionary relationships of these genes. Expression levels of AiPC4s were assessed in embryos/larvae at all developmental stages, in healthy adult tissues and in different tissues (mantles, gills, hemocytes and hearts) being processed under 32 °C stress with different time durations (0 h, 6 h, 12 h, 24 h, 3 d, 6 d and 10 d). Spatiotemporal expression profiles of AiPC4s suggested the functional roles of the genes in embryos/larvae at all developmental stages and in healthy adult tissues in bay scallop. Expression regulations (up- and down-) of AiPC4s under high-temperature stress displayed both tissue-specific and time-dependent patterns with function allocations, revealing that AiPC4s performed differentiated functions in response to thermal stress. This work provides clues of molecular function allocation of PC4 in scallops in response to thermal stress and helps in illustrating how marine bivalves resist elevated seawater temperature.

Secretory Autophagosomes from Alveolar Macrophages Exacerbate Acute Respiratory Distress Syndrome by Releasing IL-1ß.

PURPOSE: Activated alveolar macrophages (AMs) secrete extracellular vesicles and particles to mediate the inflammatory response in the acute respiratory distress syndrome (ARDS) although the underlying mechanisms are poorly understood. This study investigated whether secretory autophagosomes (SAPs) from AMs contribute to the inflammation-mediated lung injury of ARDS. METHODS: We first isolated SAPs from cell culture supernatants of RAW264.7 cells and AMs and quantified Interleukin (IL)-1ß levels in SAPs. Next, we employed a lipopolysaccharide (LPS)-induced ARDS model to investigate whether SAP-derived IL-1ß could exacerbate lung injury. Finally, we used siRNA to knockdown Rab8a, both in vitro and in vivo, to investigate the effect of Rab8a on SAP secretion and lung injury in ARDS. RESULTS: We found that AMs play an important role in ARDS by releasing a novel type of proinflammatory vesicles called SAPs that could exacerbate lung injury. SAPs are characterized as double-membrane vesicles (diameter ~200 nm) with the expression of light chain 3 (LC3). IL-1ß in SAPs is the key factor that contributes to the inflammation and lung injury in ARDS. We found that Rab8a is necessary for AMs to release SAPs with IL-1ß, and Rab8a knockdown alleviated lung injury in ARDS. CONCLUSION: This study showed the novel finding that SAPs released from AMs play a vital role in ARDS by promoting an inflammatory response and the underlying mechanism was associated with IL-1ß secretion.

Five-Year Follow-Up Study of Transurethral Plasmakinetic Resection of the Prostate for Benign Prostatic Hyperplasia.

PURPOSE: To explore the long-term clinical efficacy and safety of transurethral plasmakinetic resection of the prostate (PKRP) for benign prostatic hyperplasia (BPH). PATIENTS AND METHODS: A total of 550 patients with BPH who had undergone PKRP from October 2006 to September 2009 were enrolled in this study. All patients were evaluated at baseline and follow-up (3, 12, 24, 36, 48, 60 months postoperatively) by peak flow rate (Qmax), postvoid residual (PVR), quality of life (QoL), International Prostate Symptom Score (IPSS), and Overactive Bladder Symptom Score (OABSS). Operative details and postoperative complications regarded as safety outcomes were documented. RESULTS: A total of 467 patients completed the 5-year follow-up. The mean duration of surgery was 36.43 minutes, mean catheterization time was 48.81 hours, mean hospital stay was 4.21 days. At 60 months postoperatively, the mean Qmax increased from 6.94 mL/s at baseline to 19.28 mL/s, the mean PVR decreased from 126.33 mL to 10.45 mL, the mean IPSS score decreased from 15.79 to 7.51, the mean QoL score decreased from 4.36 to 1.91, and the mean OABSS score decreased from 6.39 to 3.65 (P < 0.001), respectively. In perioperative complications, the blood transfusion rate was 2.7%, urinary tract infection rate was 3.6%; no transurethral resection syndrome (TUR syndrome) occurred. In late complications, urethral stricture rate was 5.4%, recurrent bladder outlet obstruction rate was 2.1%, and the reoperation rate was 4.5%. CONCLUSIONS: PKRP is based on conventional monopolar transurethral resection of the prostate (TURP) and uses a bipolar plasmakinetic system. Our results indicate that the long-term clinical efficacy and safety of PKRP for BPH are remarkable. In particular, the incidence of urethral stricture, recurrent bladder outlet obstruction, and reoperation is low. We suggest that PKRP is a reliable minimally invasive technique that may be the preferred procedure for the treatment of patients with BPH.

In situ evolution of trivalent chromium process passive film on Al in a corrosive aqueous environment.

In situ neutron reflectivity (NR) is used to observe the structure and evolution of a Trivalent Chromium Process (TCP) passive film on Al in a NaCl-D(2)O solution. Using a split liquid reflectivity cell we mimicked the corrosion process on the anodic sites in alloy AA 2024-T3 in a pitting scenario. The split cell separates the anodic and cathodic reactions, allowing NR observation of the corroding anodic surface under potential control. We observed the evolution of the TCP film on the Al anode and compared the degradation of the Al with and without TCP protection. When held at 100 mV above the open-circuit potential (OCP), unprotected aluminum dissolves at a rate of 120 Å/h. By contrast, TCP-coated Al is stable up to the pitting potential (200 mV above OCP). In the passive state D(2)O molecules penetrate the bulk TCP film by partially replacing the hydrate water. In spite of exchange of hydration water, the TCP film is stable and the underlying aluminum is fully protected. The passive character of the TCP film is due to a dense layer at the metal-TCP interface and/or to suppression of ion transport in the bulk film. As the pitting potential is approached the film swells and NaCl-D(2)O solution penetrates the TCP film. At this point, 50 vol % of the TCP film is occupied by bulk NaCl-D(2)O solution. Failure occurs by aluminum dissolution under the swollen TCP film as the imbibed solution contacts the Al metal. Further increase in potential leads to complete stripping of the TCP film.

Structure and composition of trivalent chromium process (TCP) films on Al alloy.

Neutron reflectivity (NR) and X-ray reflectivity (XRR) were used to determine the structure and composition of trivalent chromium process (TCP) films on aluminum alloy AA-2024. Two deposition methods were developed: immersion and electroassisted (EA) deposition. The EA deposition method was designed to guarantee a well-defined film with a uniform structure and minimum contamination from Al and additives in the precursor solution. Quantitative NR and XRR analysis of the EA-TCP film confirmed linear growth as a function of deposition time. By analyzing both NR and XRR data on as-prepared and dried films, the film composition was determined to be Cr(2)O(3) x iH(2)O x x(ZrO(2) x jH(2)O) (i = 2.10 +/- 0.55, j = 1.60 +/- 0.45, and x = 0.85 +/- 0.14).