Polyunsaturated fatty acid-derived lipid mediator Resolvin D1 alleviates sepsis-induced disseminated intravascular coagulation via Caspase-1/Gasdermin D pyroptotic pathway.

BACKGROUND & AIMS: Sepsis-induced disseminated intravascular coagulation (DIC) is characterised by abnormal blood clotting resulting from severe infection, contributing to organ dysfunction in sepsis. Resolvin D1 (RvD1) is an endogenous lipid mediator, synthesised from the omega-3 polyunsaturated fatty acid (PUFA) docosahexaenoic acid (DHA) through enzymatic processes involving 15-LOX and 5-LOX. RvD1 is recognised for its protective properties against various inflammatory conditions. This study aims to investigate its potential to modulate coagulation dysfunction in sepsis and to evaluate coagulation disorders in septic patients. METHODS: Sepsis models were established by intraperitoneal injection LPS (20 mg/kg) or cecal ligation and puncture (CLP) followed by injection of RvD1 (10 µg/kg) or saline. The impact of RvD1 on coagulation dysfunction was assessed by clotting time and coagulation indicators such as TAT, D-dimer, PAI-1, and fibrinogen. The activity of the coagulation system in vivo was observed by evaluating dynamic microcirculation, platelets and thrombin in mice using intravital microscopy. The effect of RvD1 on pyroptosis was investigated by measuring NOD-like receptor protein 3 (NLRP3), Caspase-1, Caspase-11, and Gasdermin D (GSDMD) levels via western blot. Caspase-1 knockout mice, GSDMD knockout mice and bone marrow-derived macrophages (BMDMs) were used to elucidate the underlying mechanisms. Lastly, the concentration of RvD1 in plasma from septic patients was quantified to explore its relationship with coagulation and pyroptosis. RESULTS: RvD1 significantly attenuated coagulation dysfunction in septic mice induced by LPS and CLP, and inhibited Caspase-1/GSDMD-dependent pyroptosis in septic mice and bone marrow-derived macrophages. In septic patients, the plasma concentrations of RvD1 was negatively correlated with both coagulation-related indicators and markers of GSDMD activation. CONCLUSION: The results suggest that RvD1 can improve coagulation dysfunction in sepsis by regulating the Caspase-1/GSDMD pyroptotic pathway. Additionally, the concentration of RvD1 in septic patient plasma is related to prognosis and DIC development. RvD1 could be a potential biomarker and a promising therapeutic alternative in sepsis-induced DIC.

Diagnosis of severe community-acquired pneumonia caused by Acinetobacter baumannii through next-generation sequencing: a case report.

BACKGROUND: Acinetobacter baumannii is a gram-negative aerobic bacillus that is commonly causes of hospital-acquired infections. Community-acquired pneumonia caused by Acinetobacter baumannii (CAP-Ab) is rare but fatal if diagnosis and treatment are delayed. Conventional culture of clinical specimens is the main method for clinical diagnosis of A. baumannii infections which may suffer from limited positive rate and is time consuming. Timely and precise diagnosis of CAP-Ab remains challenging. CASE PRESENTATION: A 66-year-old man with 24 h history of acute fever and dyspnea was admitted to our hospital. He was diagnosed as severe community acquired pneumonia (CAP), septic shock, respiratory failure and acute kidney injury. Next-generation sequencing (NGS) was performed on the patient's sputum and blood, which identified numerous A. baumannii nucleotide sequences in the sample of sputum and led to the rapid diagnosis and treatment of community acquired pneumonia caused by A. baumannii. This result was confirmed by subsequent sputum culture. CONCLUSIONS: This case described that the successful application of the next generation sequencing assisting the speedy diagnosis of A. baumannii infection provides a new idea for the timely diagnosis of CAP-Ab and highlights that NGS is a promising tool in rapid etiological diagnosis of acute and severe infectious diseases.

Antioxidant status of serum bilirubin and uric acid in patients with polymyositis and dermatomyositis.

OBJECTIVE: Oxidative stress and variations in antioxidant status are implicated in the pathogenesis of inflammatory and autoimmune diseases. Polymyositis and dermatomyositis (PM/DM) are autoimmune diseases with inflammatory cells infiltrating into skeletal muscles, and the antioxidant status is still controversial. The aim of our study was to investigate the correlation between PM/DM and the antioxidant status of serum bilirubin (Tbil, Dbil and Ibil) and uric acid (UA). MATERIALS AND METHODS: We measured serum concentrations of bilirubin (Tbil, Dbil and Ibil) and uric acid in 384 individuals, including 110 PM/DM patients and 274 healthy controls. RESULTS: We found that PM/DM patients had significantly lower serum concentrations of bilirubin (Tbil and Ibil) and uric acid than healthy controls, whether male or female. Also, after separately adjusting the covariances of age and gender, Tbil, Dbil, Ibil and UA were all relevant factors for PM/DM. Moreover, there were no significant differences in serum antioxidant molecule levels between PM and DM subgroups. CONCLUSION: Our study demonstrated the low serum levels of bilirubin and uric acid in patients with PM/DM. This suggested low antioxidant status in PM/DM patients with excessive oxidative stress.

Low serum albumin concentrations are associated with disease severity in patients with myasthenia gravis.

Serum albumin (S-Alb) is a widely used biomarker of nutritional status and disease severity in patients with autoimmune diseases. We investigated the correlation between S-Alb and the severity of myasthenia gravis (MG).A total number of 166 subjects were recruited in the study. Subjects were divided into 3 groups (T1 to T3) by S-Alb levels: T1: 21.1 to 38.4 g/L, T2: 38.5 to 41.5 g/L, T3: 41.6 to 48.9 g/L. Regression analysis was performed to determine the correlation of initial albumin concentrations and the severity of disease of MG.Lower levels of S-Alb were observed in subjects with increased disease severity than those with slight disease severity, meanwhile, incidence of myasthenia crisis increased in the lower albumin tertiles (P < 0.001). The disease severity assessment was performed according to the criteria established by the Myasthenia Gravis Foundation of America. After adjusting for age, sex, body mass index (BMI), and duration of disease, it showed that higher S-Alb concentrations were associated with lower disease severity. Odds ratios (ORs) of T2 to T3 were 0.241 (95% CI: 0.103-0.566, P < 0.001), 0.140 (95% CI: 0.054-0.367, P < 0.001) when compared with subjects in the T1, respectively. When subjects were stratified into hypoalbuminemia and normal albumin groups, we found that the association between S-Alb and MG remained significant in the hypoalbuminemia group only (OR: 0.693, 95% CI: 0.550-0.874, P = 0.002) after further adjustment for age, sex, BMI, and duration of disease.This is the first study to demonstrate that S-Alb was independently associated with MG severity. In patients with low S-Alb, S-Alb concentration could be a potential biomarker for MG disability.

Platelet-to-White Blood Cell Ratio: A Prognostic Predictor for 90-Day Outcomes in Ischemic Stroke Patients with Intravenous Thrombolysis.

BACKGROUND: This study is aimed to investigate the relationship between platelet-to-white blood cell ratio (PWR) and 90-day outcomes in acute stroke patients with intravenous thrombolysis (IVT). MATERIALS AND METHODS: A retrospective analysis was performed on 168 patients receiving IVT for acute ischemic stroke. Complete blood count evaluation was conducted at admission before IVT. A modified Rankin Scale (mRS) score of 3-6 at 90 days was considered an unfavorable outcome. RESULTS: A total of 168 patients were included from 2013 to 2015. The mean age of the sample was 64.6 (±12.3) years, and 23.2% were women. The median baseline National Institutes of Health Stroke Scale score was 7.5 (interquartile range [IQR] 8.0) and the 90-day mRS score was 2 (IQR 2). In our multivariate logistic regression model, a PWR greater than 23.52 (odds ratio .454, 95% confidence interval: .212-.973, P < .050) was a predictor of 90-day outcomes. In addition, there was a significant difference in the PWR values of patients between favorable outcome and unfavorable outcome in the large-artery atherosclerosis subtype (28.241 ± 11.581 and 21.899 ± 9.107, respectively; P = .005). CONCLUSIONS: The PWR at admission predicts 90-day outcomes in ischemic stroke patients with IVT. With the easy and routine use of hemogram analysis, the PWR should be investigated in further prospective randomized controlled trials of acute stroke.

Transplantation of olfactory ensheathing cells promotes partial recovery in rats with experimental autoimmune encephalomyelitis.

OBJECTIVE: This study was to investigate the efficacy of olfactory ensheathing cell (OEC) transplantation on experimental autoimmune encephalomyelitis (EAE). METHODS: EAE models were established by guinea pig spinal cord homogenate (GPSCH) immunization in Lewis rats. OECs were purified and cultured from the olfactory nerve layer of SD rats, and then transplanted to the EAE models through the vena caudalis (Group A) or into the lateral cerebral ventricle (Group B). Neurological function scores and body weights were daily recorded following transplantation, and histological analysis was performed to assess the pathological changes in EAE rats. RESULTS: Cultured cells mainly exhibited bipolar or tripolar morphology, and the majority of these cells were positive for NGFR p75 staining. Neurological function scoring and the body weight measurement showed that, OEC transplantation could significantly improve the performance of EAE rats, and similar results were observed for the transplantation through the vena caudalis and into the lateral cerebral ventricle. Moreover, the transplanted OECs accumulated to the lesions in the brains of EAE rats, in spite of the different transplantation approaches. However, no significant differences in histopathology (HE and LFB staining) were observed between the OEC-transplanted groups and the control group. CONCLUSION: OEC transplantation could exert beneficial effects in the treatment of EAE, no matter which the cells were transplanted through the vena caudalis or into the lateral cerebral ventricle. Our findings might provide evidence for the clinical treatment of multiple sclerosis with cell transplantation.