Blood substitution therapy rescues the brain of mice from ischemic damage

Acute stroke causes complex, pathological, and systemic responses that have not been treatable by any single medication. In this study, using a murine transient middle cerebral artery occlusion stroke model, a novel therapeutic strategy is proposed, where blood replacement (BR) robustly reduces infarctions and improves neurological deficits in mice. Our analyses of immune cell subsets suggest that BR therapy substantially decreases neutrophils in blood following a stroke. Electrochemiluminescence detection demonstrates that BR therapy reduces cytokine storm in plasma and ELISA demonstrates reduced levels of matrix metalloproteinase-9 (MMP-9) in the plasma and brains at different time points post-stroke. Further, we have demonstrated that the addition of MMP-9 to the blood diminishes the protective effect of the BR therapy. Our study is the first to show that BR therapy leads to profoundly improved stroke outcomes in mice and that the improved outcomes are mediated via MMP-9. These results offer new insights into the mechanisms of stroke damage

Mitochondrial Impairment in Cerebrovascular Endothelial Cells is Involved in the Correlation between Body Temperature and Stroke Severity

Stroke is the second leading cause of death worldwide. The prognostic influence of body temperature on acute stroke in patients has been recently reported; however, hypothermia has confounded experimental results in animal stroke models. This work aimed to investigate how body temperature could prognose stroke severity as well as reveal a possible mitochondrial mechanism in the association of body temperature and stroke severity. Lipopolysaccharide (LPS) compromises mitochondrial oxidative phosphorylation in cerebrovascular endothelial cells (CVECs) and worsens murine experimental stroke. In this study, we report that LPS (0.1 mg/kg) exacerbates stroke infarction and neurological deficits, in the mean time LPS causes temporary hypothermia in the hyperacute stage during 6 hours post-stroke. Lower body temperature is associated with worse infarction and higher neurological deficit score in the LPS-stroke study. However, warming of the LPS-stroke mice compromises animal survival. Furthermore, a high dose of LPS (2 mg/kg) worsens neurological deficits, but causes persistent severe hypothermia that conceals the LPS exacerbation of stroke infarction. Mitochondrial respiratory chain complex I inhibitor, rotenone, replicates the data profile of the LPS-stroke study. Moreover, we have confirmed that rotenone compromises mitochondrial oxidative phosphorylation in CVECs. Lastly, the pooled data analyses of a large sample size (n=353) demonstrate that stroke mice have lower body temperature compared to sham mice within 6 hours post-surgery; the body temperature is significantly correlated with stroke outcomes; linear regression shows that lower body temperature is significantly associated with higher neurological scores and larger infarct volume. We conclude that post-stroke body temperature predicts stroke severity and mitochondrial impairment in CVECs plays a pivotal role in this hypothermic response. These novel findings suggest that body temperature is prognostic for stroke severity in experimental stroke animal models and may have translational significance for clinical stroke patients - targeting endothelial mitochondria may be a clinically useful approach for stroke therapy

Ischemic Stroke Alters Immune Cell Niche and Chemokine Profile in Mice Independent of Spontaneous Bacterial Infection

Background The aim of this study is to report the long-term efficacy and safety of thoracoscopic epicardial left atrial ablation (TELA) in patients with paroxysmal atrial fibrillation (AF). Methods This was a retrospective review of medical records. We included all patients diagnosed with paroxysmal AF who underwent TELA at our institution between 04/2011 and 06/2017. TELA included pulmonary vein isolation, LA dome lesions and LA appendage exclusion. All (n = 55) patients received an implantable loop recorder (ILR), 30 days post-operatively. Antiarrhythmic and anticoagulation therapy were discontinued at 90 and 180 days postoperatively, respectively, if patients were free of AF recurrence. Failure was defined as ≥two minutes of continuous AF, or atrial tachycardia. Results Fifty-five patients (78% males, mean age = 61.6 years) qualified for the study. The average duration in AF was 3.64 +/− 3.4 years, mean CHA2DS2-VASc Score was 2.0 +/− 1.6. The procedure was attempted in 57 patients and completed successfully in 55 (96.5%). Two patients experienced a minor pulmonary vein bleed that was managed conservatively. Post procedure, one patient experienced pulmonary edema, another experienced a pneumothorax requiring a chest tube and another experienced acute respiratory distress syndrome resulting in longer hospitalization. Otherwise, there were no major procedural complications. Success rates were 89.1% (n = 49/55), 85.5% (n = 47/55) and 76.9% (n = 40/52) at 6, 12 and 24 months, respectively. In the multivariate cox-proportional hazard model, survival at the mean of covariates was 86 and 74% at 12 and 24 months, respectively. Conclusion In this single center experience, TELA was a safe and efficacious procedure for patients with paroxysmal AF

Clinical identification and microbiota analysis of Chlamydia psittaci- and Chlamydia abortus- pneumonia by metagenomic next-generation sequencing

IntroductionRecently, the incidence of chlamydial pneumonia caused by rare pathogens such as C. psittaci or C. abortus has shown a significant upward trend. The non-specific clinical manifestations and the limitations of traditional pathogen identification methods determine that chlamydial pneumonia is likely to be poorly diagnosed or even misdiagnosed, and may further result in delayed treatment or unnecessary antibiotic use. mNGS's non-preference and high sensitivity give us the opportunity to obtain more sensitive detection results than traditional methods for rare pathogens such as C. psittaci or C. abortus. MethodsIn the present study, we investigated both the pathogenic profile characteristics and the lower respiratory tract microbiota of pneumonia patients with different chlamydial infection patterns using mNGS.ResultsMore co-infecting pathogens were found to be detectable in clinical samples from patients infected with C. psittaci compared to C. abortus, suggesting that patients infected with C. psittaci may have a higher risk of mixed infection, which in turn leads to more severe clinical symptoms and a longer disease course cycle. Further, we also used mNGS data to analyze for the first time the characteristic differences in the lower respiratory tract microbiota of patients with and without chlamydial pneumonia, the impact of the pattern of Chlamydia infection on the lower respiratory tract microbiota, and the clinical relevance of these characteristics. Significantly different profiles of lower respiratory tract microbiota and microecological diversity were found among different clinical subgroups, and in particular, mixed infections with C. psittaci and C. abortus resulted in lower lung microbiota diversity, suggesting that chlamydial infections shape the unique lung microbiota pathology, while mixed infections with different Chlamydia may have important effects on the composition and diversity of the lung microbiota. DiscussionThe present study provides possible evidences supporting the close correlation between chlamydial infection, altered microbial diversity in patients' lungs and clinical parameters associated with infection or inflammation in patients, which also provides a new research direction to better understand the pathogenic mechanisms of pulmonary infections caused by Chlamydia

Epstein-Barr virus genes in patients with acute, chronic and recurrent hemophagocytosis

Hemophagocytic lymphohistiocytosis (HLH), a rare disorder primarily of childhood, typically presents with fever, hepatosplenomegaly, lymphadenopathy, and sometimes vague or dramatic central nervous system (CNS) dysfunction. Leading triggering agents in HLH are viruses of the herpes group, especially Epstein-Barrvirus (EBV). In addition to high concentrations of cytokines, states of EBV-infected T/NK cells appear to play a role in the development of EBV-associated HLH. Since EBV establishes a life-long persistent infection in more than 90% of the population worldwide, it is necessary to know how EBV may be related to HLH. We investiged 9 patients with histories of acute, chronic, and recurrent HLH, the relationships between the valuable disease marker of HLH, the concentration of soluble Cluster of Differentiation antigen (sCD25) in their plasma from different time points, and the EBV target genes, Epstein-Barrvirus nuclear antigen 1 (EBNA1), EBNA2, EBNA3C, EBV lytic activation 1 (BZLF1), BMLF1, Nonglycosylated membrane protein 1 (BNRF1) and latent membrane protein 1 (LMP1) of paired samples from these 9 patients. Our results demonstrated that BZLF1 and EBNA3c genes were present in active HLH patients, which are found in whole blood, and isolated cells concomitantly with high concentration of plasma sCD25. In conclusion: BZLF1 and EBNA3c genes were associated with active HLH. Single cell PCR appears to be a prominent set up be applied for the contributuion of EBV in HLH as well as other diseases including tumor manifestation

Blood substitution therapy rescues the brain of mice from ischemic damage

Acute stroke causes complex, pathological, and systemic responses which remain challenging to treat. Here, the authors show that substituting the blood of stroke model mice with whole-blood from naive healthy donor mice reduces infarct volume and improves neurological deficits

Evaluation of Bioenergetic Function in Cerebral Vascular Endothelial Cells

The integrity of the blood-brain-barrier (BBB) is critical to prevent brain injury. Cerebral vascular endothelial (CVE) cells are one of the cell types that comprise the BBB; these cells have a very high-energy demand, which requires optimal mitochondrial function. In the case of disease or injury, the mitochondrial function in these cells can be altered, resulting in disease or the opening of the BBB. In this manuscript, we introduce a method to measure mitochondrial function in CVE cells by using whole, intact cells and a bioanalyzer. A mito-stress assay is used to challenge the cells that have been perturbed, either physically or chemically, and evaluate their bioenergetic function. Additionally, this method also provides a useful way to screen new therapeutics that have direct effects on mitochondrial function. We have optimized the cell density necessary to yield oxygen consumption rates that allow for the calculation of a variety of mitochondrial parameters, including ATP production, maximal respiration, and spare capacity. We also show the sensitivity of the assay by demonstrating that the introduction of the microRNA, miR-34a, leads to a pronounced and detectable decrease in mitochondrial activity. While the data shown in this paper is optimized for the bEnd.3 cell line, we have also optimized the protocol for primary CVE cells, further suggesting the utility in preclinical and clinical models