COVID-19 is a disease with heterogeneous clinical appearances. Most patients are asymptomatic or exhibit mild to moderate symptoms; approximately 15% progress to severe pneumonia and about 5% are eventually admitted to the intensive care unit (ICU) due to acute respiratory distress syndrome (ARDS), septic shock and/ or multiple organ failure. ICU patients respond poorly to currently available treatments and exhibit a high mortality rate. 1-3 Inadequate identification of the determinants of fatal outcomes is one of the major obstacles to the improvement of the outcomes in severe COVID-19 patients. A previous study reported a scoring system (COVID-GRAM) which accurately predicted the occurrence of critical illness in hospitalized COVID-19 patients. 4 Damage-associated molecular patterns (DAMPs), or alarmins, are a number of molecules, released by stressed cells undergoing microbial infection or sterile injury, that act as danger signals to promote and exacerbate the inflammatory response. 5,6 Of note, the serum level of S100A8/A9 and HMGB1 was found to be correlated with both the severity of pathogen-associated tissue damage and excessive cytokine storm. 7 Despite the hypothesis that S100A8/A9 and HMGB1 are significantly involved in COVID-19, so far, no study has yet tried to substantiate the hypothesis. In this study, we aimed to define the role of S100A8/ A9 and HMGB1 in progression to a fatal outcome and develop clinically relevant risk strata for COVID-19 patients. A total of 121 patients were enrolled in this retrospective study, of which 40 patients were in ICU and 81 patients in general wards at enrollment (Table S1). ICU Patients had much higher COVID-GRAM risk scores in comparison to those in general wards. Complications, including ARDS, sepsis, septic shock, secondary infection, acute renal injury, acute cardiac injury or failure, were more frequent in CCOVID-19 patients admitted to ICU. As of the cutoff date of April 30, 2020, most of non-ICU patients (96.3%) had been discharged alive, while 82.5% of ICU patients had died in ICU.

Tiotropium resulted in a higher FEV than placebo at 24 months and ameliorated the annual decline in the FEV after bronchodilator use in patients with COPD of GOLD stage 1 or 2. (Funded by Boehringer Ingelheim and others; Tie-COPD ClinicalTrials.gov number, NCT01455129 .).

Background A multitude of epidemiological studies have shown that ambient fine particulate matter 2.5 (diameter < 2.5um; PM 2.5 ) was associated with increased morbidity and mortality of chronic obstructive pulmonary disease (COPD). However, the underlying associated mechanisms have not yet been elucidated. We conducted this study to investigate the role of PM 2.5 in the development of COPD and associated mechanisms. Methods We firstly conducted a cross-sectional study in Chinese han population to observe PM 2.5 effects on COPD morbidity. Then, in vitro, we incubated human bronchial epithelial cells to different concentrations of PM 2.5 for 24 h. The expression levels of IL-6 and IL-8 were detected by ELISA and the levels of MMPs, TGF-β1, fibronectin and collagen was determined by immunoblotting. In vivo, we subjected C57BL/6 mice to chronic prolonged exposure to PM 2.5 for 48 weeks to study the influence of PM 2.5 exposure on lung function, pulmonary structure and inflammation. Results We found that the effect of PM 2.5 on COPD morbidity was associated with its levels and that PM 2.5 and cigarette smoke could have a synergistic impact on COPD development and progression. Both vitro and vivo studies demonstrated that PM 2.5 exposure could induce pulmonary inflammation, decrease lung function, and cause emphysematous changes. Furthermore, PM 2.5 could markedly aggravated cigarette smoke-induced changes. Conclusions In short, we found that prolonged chronic exposure to PM 2.5 resulted in decreased lung function, emphysematous lesions and airway inflammation. Most importantly, long-term PM 2.5 exposure exacerbateed cigarette smoke-induced changes in COPD.

BackgroundWe aimed to determine the risk conferred by metabolic syndrome (METS) and diabetes mellitus (DM) to recurrent stroke in patients with minor ischemic stroke or transient ischemic attack from the CHANCE (Clopidogrel in High‐risk patients with Acute Non‐disabling Cerebrovascular Events) trial.Methods and ResultsIn total, 3044 patients were included. Patients were stratified into 4 groups: neither, METS only, DM only, or both. METS was defined using the Chinese Diabetes Society (CDS) and International Diabetes Foundation (IDF) definitions. The primary outcome was new stroke (including ischemic and hemorrhagic) at 90 days. A multivariable Cox regression model was used to assess the relationship of METS and DM status to the risk of recurrent stroke adjusted for potential covariates. Using the CDS criteria of METS, 53.2%, 17.2%, 19.8%, and 9.8% of patients were diagnosed as neither, METS only, DM only, and both, respectively. After 90 days of follow‐up, there were 299 new strokes (293 ischemic, 6 hemorrhagic). Patients with DM only (16.1% versus 6.8%; adjusted hazard ratio 2.50, 95% CI 1.89–3.39) and both (17.1% versus 6.8%; adjusted hazard ratio 2.76, 95% CI 1.98–3.86) had significantly increased rates of recurrent stroke. No interaction effect of antiplatelet therapy by different METS or DM status for the risk of recurrent stroke (P=0.82 for interaction in the fully adjusted model of CDS) was observed. Using the METS (IDF) criteria demonstrated similar results.ConclusionsConcurrent METS and DM was associated with an increased risk of recurrent stroke in patients with minor stroke and transient ischemic attack.

BackgroundThere are several mechanisms, including inflammation, oxidative stress and abnormal calcium homeostasis, involved in the pathogenesis of atrial fibrillation. In diabetes mellitus (DM), increased oxidative stress may be attributable to higher xanthine oxidase activity. In this study, we examined the relationship between oxidative stress and atrial electrical and structural remodeling, and calcium handling abnormalities, and the potential beneficial effects of the xanthine oxidase inhibitor allopurinol upon these pathological changes.Methods and ResultsNinety rabbits were randomly and equally divided into 3 groups: control, DM, and allopurinol‐treated DM group. Echocardiographic and hemodynamic assessments were performed in vivo. Serum and tissue markers of oxidative stress and atrial fibrosis, including the protein expression were examined. Atrial interstitial fibrosis was evaluated by Masson trichrome staining. ICaL was measured from isolated left atrial cardiomyocytes using voltage‐clamp techniques. Confocal microscopy was used to detect intracellular calcium transients. The Ca2+ handling protein expression was analyzed by Western blotting. Mitochondrial‐related proteins were analyzed as markers of mitochondrial function. Compared with the control group, rabbits with DM showed left ventricular hypertrophy, increased atrial interstitial fibrosis, oxidative stress and fibrosis markers, ICaL and intracellular calcium transient, and atrial fibrillation inducibility. These abnormalities were alleviated by allopurinol treatment.ConclusionsAllopurinol, via its antioxidant effects, reduces atrial mechanical, structural, ion channel remodeling and mitochondrial synthesis abnormalities induced by DM‐related increases in oxidative stress.

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Background: Oxidative stress contributes to adverse atrial remodeling in diabetes mellitus. This remodeling can be prevented by the PPAR-γ agonist pioglitazone via its antioxidant and anti-inflammatory effects. In this study, we examined the molecular mechanisms underlying the protective effects of pioglitazone on atrial remodeling in a rabbit model of diabetes.Methods: Rabbits were randomly divided into control, diabetic, and pioglitazone-treated diabetic groups. Echocardiographic, hemodynamic, and electrophysiological parameters were measured. Serum PPAR-γ levels, serum and tissue oxidative stress and inflammatory markers, mitochondrial morphology, reactive oxygen species (ROS) production rate, respiratory function, and mitochondrial membrane potential (MMP) levels were measured. Protein expression of the pro-fibrotic marker TGF-β1, the PPAR-γ coactivator-1α (PGC-1α), and the mitochondrial proteins (biogenesis-, fusion-, and fission-related proteins) was measured. HL-1 cells were transfected with PGC-1α small interfering RNA (siRNA) to determine the underlying mechanisms of pioglitazone improvement of mitochondrial function under oxidative stress.Results: The diabetic group demonstrated a larger left atrial diameter and fibrosis area than the controls, which were associated with a higher incidence of inducible atrial fibrillation (AF). The lower serum PPAR-γ level was associated with lower PGC-1α and higher NF-κB and TGF-β1 expression. Lower mitochondrial biogenesis (PGC-1α, NRF1, and TFAM)-, fusion (Opa1 and Mfn1)-, and fission (Drp1)-related proteins were detected. Mitochondrial swelling, higher mitochondrial ROS, lower respiratory control rate, and lower MMP were observed. The pioglitazone group showed a reversal of structural remodeling and a lower incidence of inducible AF, which were associated with higher PPAR-γ and PGC-1α. The pioglitazone group had lower NF-κB and TGF-β1 expression levels, whereas biogenesis-, fusion-, and fission-related protein expression was higher. Further, mitochondrial structure and function were improved. In HL-1 cells, PGC-1α siRNA transfection blunted the effect of pioglitazone on Mn-SOD protein expression and MMP collapse in H2O2-treated cells.Conclusion: Diabetes mellitus induces adverse atrial structural, electrophysiological remodeling, and mitochondrial damage and dysfunction. Pioglitazone prevented these abnormalities through the PPAR-γ/PGC-1α pathway.