Construction of an Artificial Light-Harvesting System with Efficient Photocatalytic Activity in an Aqueous Solution Based on a FRET-Featuring Metallacage.

Over the past few decades, the design and construction of high-efficiency artificial light-harvesting systems (LHSs) involving multistep fluorescence-resonance energy transfer (FRET) processes have gradually received considerable attention within wide fields ranging from supramolecular chemistry to chemical biology and even materials science. Herein, through coordination-driven self-assembly, a novel tetragonal prismatic metallacage featuring a FRET process using tetraphenylethene (TPE) units as donors and BODIPY units as acceptors has been conveniently synthesized. Subsequently, taking advantage of supramolecular hydrophobic interactions, a promising artificial LHS involving two-step FRET processes from TPE to BODIPY and then to Nile Red (NiR) has been successfully fabricated in an aqueous solution using the FRET-featuring metallacage, NiR, and an amphiphilic polymer (mPEG-DSPE). Notably, this obtained aqueous LHS exhibits highly efficient photocatalytic activity in the dehalogenation of a bromoacetophenone derivate. This study provides a unique strategy for fabricating artificial LHSs in aqueous solutions with multistep FRET processes and further promotes the future development of mimicking the photosynthesis process.

Transcutaneous Electrical Acustimulation Ameliorates Motion Sickness Induced by Rotary Chair in Healthy Subjects: A Prospective Randomized Crossover Study.

OBJECTIVES: Motion sickness (MS) is a common physiological response to real or virtual motion. The purpose of this study was to investigate the effects of transcutaneous electrical acustimulation (TEA) on MS and the underlying mechanisms in healthy subjects. MATERIALS AND METHODS: A total of 50 healthy participants were recruited and randomly assigned into two groups to complete two separate sessions in a crossover study. A Coriolis rotary chair was used as a model to provoke severe MS. The total tolerable rotation time and Graybiel scoring scale were recorded. Gastric slow waves were detected by electrogastrogram. The autonomic nervous function, including the vagal activity, was evaluated by the analysis of heart rate variability derived from the electrocardiogram recording. The serum levels of arginine vasopressin (AVP) and norepinephrine (NE) were examined. RESULTS: Of note, 22 participants in TEA and only 11 participants in the sham-TEA session completed the entire five-rotation MS stimuli (p = 0.019). TEA significantly prolonged the total tolerable rotation time of MS stimuli (220.4 ± 11.59 vs 173.6 ± 12.3 seconds, p < 0.001) and lowered MS symptom scores (12.56 ± 2.03 vs 22.06 ± 3.0, p < 0.001). TEA improved the percentage of normal gastric slow waves, compared with sham-TEA (56.0 ± 2.1% vs 51.6 ± 2.0%, p = 0.033). TEA also significantly enhanced vagal activity compared with sham-TEA (0.41 ± 0.02 vs 0.31 ± 0.02, p < 0.001). In addition, the increased serum levels of AVP and NE on MS stimulation were markedly suppressed by TEA treatment, compared with sham-TEA (AVP, 56.791 ± 4.057 vs 79.312 ± 10.036 ng/mL, p = 0.033; NE, 0.388 ± 0.037 vs 0.501 ± 0.055 ng/mL, p = 0.021). CONCLUSIONS: Needleless TEA is a potent therapeutic approach for severe MS, as it increases participants' tolerance and ameliorates MS symptoms, which may be attributed to the integrative effects of TEA on autonomic functions and neuroendocrine balance.

Critical roles of cytokine storm and secondary bacterial infection in acute kidney injury development in COVID-19: A multi-center retrospective cohort study.

Acute kidney injury (AKI) may develop in patients with coronavirus disease 2019 (COVID-19) and is associated with in-hospital death. We investigated the incidence of AKI in 223 hospitalized COVID-19 patients and analyzed the influence factors of AKI. The incidence of cytokine storm syndrome and its correlation with other clinicopathologic variables were also investigated. We retrospectively enrolled adult patients with virologically confirmed COVID-19 who were hospitalized at three hospitals in Wuhan and Guizhou, China between February 13, 2020, and April 8, 2020. We included 124 patients with moderate COVID-19 and 99 with severe COVID-19. AKI was present in 35 (15.7%) patients. The incidence of AKI was 30.3% for severe COVID-19 and 4.0% for moderate COVID-19 (p < 0.001). Furthermore, cytokine storm was found in 30 (13.5%) patients and only found in the severe group. Kidney injury at admission (odds ratio [OR]: 3.132, 95% confidence interval [CI]: 1.150-8.527; p = 0.025), cytokine storm (OR: 4.234, 95% CI: 1.361-13.171; p = 0.013), and acute respiratory distress syndrome (ARDS) (OR: 7.684, 95% CI: 2.622-22.523; p < 0.001) were influence factors of AKI. Seventeen (48.6%) patients who received invasive mechanical ventilation developed AKI, of whom 64.7% (11/17) died. Up to 86.7% of AKI patients with cytokine storms may develop a secondary bacterial infection. The leukocyte counts were significantly higher in AKI patients with cytokine storm than in those without (13.0 × 109/L, interquartile range [IQR] 11.3 vs. 8.3 × 109/L, IQR 7.5, p = 0.005). Approximately 1/6 patients with COVID-19 eventually develop AKI. Kidney injury at admission, cytokine storm and ARDS are influence factors of AKI. Cytokine storm and secondary bacterial infections may be responsible for AKI development in COVID-19 patients.

Downregulation of exosome-encapsulated miR-548c-5p is associated with poor prognosis in colorectal cancer.

The role of circulating exosomal microRNAs (miRNAs) in colorectal cancer (CRC) has drawn more and more attention during the past few years. Previously, we have identified several specific miRNAs in serum exosomes as potential CRC biomarkers. However, little is known about the association between exosome-encapsulated miR-548c-5p and outcomes of patients with CRC. In the current study, the expression of serum exosomal miR-548c-5p was investigated by quantitative real-time polymerase chain reaction. Its correlation with CRC prognosis was estimated by Kaplan-Meier survival and log-rank tests. Cox regression analysis based on uni- and multivariate analyses was performed to estimate the relationship of exosome-encapsulated miR-548c-5p with the clinicopathological factors of patients with CRC. Reduced levels of serum exosomal miR-548c-5p were more significant in CRC patients with liver metastasis and at later TNM stage (III/IV tumor stages). Serum exosomal miR-548c-5p could inhibit the proliferation of CRC cells, while the precise molecular mechanisms warranted further elucidation. In addition, decreased levels of serum exosomal miR-548c-5p were independently associated with shorter overall survival in CRC adjusted by age, sex, tumor grade vascular infiltration, TNM stage (III/IV tumor stages) and metastasis (hazard ratio = 3.40, 95% confidence interval 1.02-11.27; P = 0.046). The downregulation of exosomal miR-548c-5p in serum predicts poor prognosis in patients with CRC. Exosomal miR-548c-5p may be a critical biomarker for CRC diagnosis and prognosis.

Incomplete intestinal obstruction as the possible main complaint in Behcet's disease after surgery for recurrent abdominal aortic pseudoaneurysms: a case report and literature review.

BACKGROUND: Behcet's disease (BD) is a systemic vasculitis characterized by oral and genital aphthosis, and ocular and skin lesions. The disease is involved in vascular, gastrointestinal, and central nervous systems. Vasculitis may exacerbate fatal problems, such as anastomotic pseudoaneurysms. If the mesenteric vessels are involved, severe abdominal symptoms such as intestinal obstruction may occur. CASE PRESENTATION: This case report describes a young female patient who suffered from BD with recurrent abdominal aortic pseudoaneurysms, as well as deep venous thrombosis and subsequent complications of incomplete intestinal obstruction. This patient first underwent stent grafting, which was followed by rupture of two newly formed anastomotic pseudoaneurysms within six months. Emergency open surgical repair (OSR) was then performed on the ruptured pseudoaneurysms. Thrombosis and incomplete ileus occurred five months after surgery. This case was unique due to the presence of incomplete intestinal obstruction being the possible main complaint for a patient with Behcet's disease, and it is the first ever case to be reported. CONCLUSION: Intestinal obstruction may present as the possible main complaint in BD. Careful and attentive strategy should be carried out to prevent fatal outcomes.

Effects of fluid resuscitation with 0.9% saline versus a balanced electrolyte solution on acute kidney injury in a rat model of sepsis*.

OBJECTIVE: To compare the acute effects of 0.9% saline versus a balanced electrolyte solution on acute kidney injury in a rat model of sepsis. DESIGN: Controlled laboratory experiment. SETTING: University laboratory. SUBJECTS: Sixty adult, male Sprague-Dawley rats. INTERVENTIONS: We induced sepsis by cecal ligation and puncture and randomized animals to receive fluid resuscitation with either 0.9% saline or Plasma-Lyte solution for 4 hours after 18 hours of cecal ligation and puncture (10 mL/kg in the first hour and 5 mL/kg in the next 3 hr). Blood and urine specimens were obtained from baseline, 18 hours after cecal ligation and puncture, immediately after 4 hours fluid resuscitation, and 24 hours later. We measured blood gas, plasma electrolytes, creatinine, interleukin-6, cystatin C, and neutrophil gelatinase-associated lipocalin concentrations. We also analyzed urine for cystatin C and neutrophil gelatinase-associated lipocalin. We used Risk, Injury, Failure, Loss and End-stage criteria for creatinine to assess severity of acute kidney injury. We observed all animals for survival up to 1 day after resuscitation. Surviving animals were killed for kidney histology. Finally, we carried out an identical study in 12 healthy animals. MEASUREMENTS AND MAIN RESULTS: Compared with Plasma-Lyte, 0.9% saline resuscitation resulted in significantly greater blood chloride concentrations (p < 0.05) and significantly decreased pH and base excess. Acute kidney injury severity measured by RIFLE criteria was increased with 0.9% saline compared with Plasma-Lyte resuscitation (p < 0.05), and these results were consistent with kidney histology and biomarkers of acute kidney injury. Twenty-four-hour survival favored Plasma-Lyte resuscitation (76.6% vs 53.3%; p = 0.03). Finally, in healthy animals, we found no differences between fluids and no evidence of acute kidney injury. CONCLUSION: Volume resuscitation with Plasma-Lyte resulted in less acidosis and less kidney injury and improved short-term survival when compared with 0.9% saline in this experimental animal model of sepsis.

Modulation of chemokine gradients by apheresis redirects leukocyte trafficking to different compartments during sepsis, studies in a rat model.

INTRODUCTION: Prior work suggests that leukocyte trafficking is determined by local chemokine gradients between the nidus of infection and the plasma. We recently demonstrated that therapeutic apheresis can alter immune mediator concentrations in the plasma, protect against organ injury, and improve survival. Here we aimed to determine whether the removal of chemokines from the plasma by apheresis in experimental peritonitis changes chemokine gradients and subsequently enhances leukocyte localization into the infected compartment, and away from healthy tissues. METHODS: In total, 76 male adult Sprague-Dawley rats weighing 400 g to 600 g were included in this study. Eighteen hours after inducing sepsis by cecal ligation and puncture, we randomized these rats to apheresis or sham treatment for 4 hours. Cytokines, chemokines, and leukocyte counts from blood, peritoneal cavity, and lung were measured. In a separate experiment, we labeled neutrophils from septic donor animals and injected them into either apheresis or sham-treated animals. All numeric data with normal distributions were compared with one-way analysis of variance, and numeric data not normally distributed were compared with the Mann-Whitney U test. RESULTS: Apheresis significantly removed plasma cytokines and chemokines, increased peritoneal fluid-to-blood chemokine (C-X-C motif ligand 1, ligand 2, and C-C motif ligand 2) ratios, and decreased bronchoalveolar lavage fluid-to-blood chemokine ratios, resulting in enhanced leukocyte recruitment into the peritoneal cavity and improved bacterial clearance, but decreased recruitment into the lung. Apheresis also reduced myeloperoxidase activity and histologic injury in the lung, liver, and kidney. These Labeled donor neutrophils exhibited decreased localization in the lung when infused into apheresis-treated animals. CONCLUSIONS: Our results support the concept of chemokine gradient control of leukocyte trafficking and demonstrate the efficacy of apheresis to target this mechanism and reduce leukocyte infiltration into the lung.

Correction: ensemble models of neutrophil trafficking in severe sepsis.

[This corrects the article on p. e1002422 in vol. 8.].

Ensemble models of neutrophil trafficking in severe sepsis.

A hallmark of severe sepsis is systemic inflammation which activates leukocytes and can result in their misdirection. This leads to both impaired migration to the locus of infection and increased infiltration into healthy tissues. In order to better understand the pathophysiologic mechanisms involved, we developed a coarse-grained phenomenological model of the acute inflammatory response in CLP (cecal ligation and puncture)-induced sepsis in rats. This model incorporates distinct neutrophil kinetic responses to the inflammatory stimulus and the dynamic interactions between components of a compartmentalized inflammatory response. Ensembles of model parameter sets consistent with experimental observations were statistically generated using a Markov-Chain Monte Carlo sampling. Prediction uncertainty in the model states was quantified over the resulting ensemble parameter sets. Forward simulation of the parameter ensembles successfully captured experimental features and predicted that systemically activated circulating neutrophils display impaired migration to the tissue and neutrophil sequestration in the lung, consequently contributing to tissue damage and mortality. Principal component and multiple regression analyses of the parameter ensembles estimated from survivor and non-survivor cohorts provide insight into pathologic mechanisms dictating outcome in sepsis. Furthermore, the model was extended to incorporate hypothetical mechanisms by which immune modulation using extracorporeal blood purification results in improved outcome in septic rats. Simulations identified a sub-population (about 18% of the treated population) that benefited from blood purification. Survivors displayed enhanced neutrophil migration to tissue and reduced sequestration of lung neutrophils, contributing to improved outcome. The model ensemble presented herein provides a platform for generating and testing hypotheses in silico, as well as motivating further experimental studies to advance understanding of the complex biological response to severe infection, a problem of growing magnitude in humans.

Development of venovenous extracorporeal blood purification circuits in rodents for sepsis.

BACKGROUND: Unlike pharmacologic interventions in sepsis, extracorporeal blood purification, which is widely used in septic patients, is not typically studied in experimental rodents. Most of the previous studies have performed extracorporeal blood purification in larger animals and typically use arteriovenous (AV) vascular access. We developed a venovenous (VV) purification model in the rat as an adjunct for the treatment of sepsis. METHODS: Using adult male Sprague-Dawley rats, we cannulated the femoral artery or vein and the jugular vein with P50 tubing and created an AV or VV circuit. Blood flow was maintained by arterial pressure in the AV circuit, whereas in the VV circuit the blood flow was regulated using a rotary pump. The safety of this circuit was evaluated using the changes of blood interleukin 6, rectal temperature, and 7-d survival with sham extracorporeal circulation (circuit connection without treatment) compared with the control (without circuit). The main side complications of this VV circuit were compared with those of the AV circuit. RESULTS: The differences in interleukin 6, body temperature, and cumulative survival were not statistically significant after extracorporeal circulation. The main complications of extracorporeal circulation occurred less often with VV compared with AV therapy: massive bleeding (2.5% versus 15%, P = 0.04); clot formation (2.5% versus 15%, P = 0.04). This VV circuit has been successfully used in different septic rodent models with different techniques (hemoadsorption and hemofiltration). CONCLUSIONS: VV blood purification in a rodent model appears to be effective and is safer than AV circuit.

Perioperative fluids: a clear road ahead?

PURPOSE OF REVIEW: There is significant controversy for perioperative fluid management. This review discusses the evidence from clinical studies, basic research, and systematic reviews to provide a summary of the current best practice in this area. RECENT FINDINGS: Recent evidence has challenged the long-held contention that use of colloids results in substantially less fluid volumes to achieve resuscitation endpoints. Meanwhile, evidence that hydroxyethyl starch does carry a risk of renal toxicity is now strong. Mounting evidence also points to a hazard, especially for the kidney, when large volumes of saline are used. A patient's clinical condition may also determine the deposition of infused fluids in the body. Total positive fluid balance is an indicator of adverse clinical outcomes, though a cause-effect relationship has not been firmly established. The optimal perioperative fluid management requires a balance of the beneficial and adverse effects of intravenous fluid. SUMMARY: Although potentially life-saving, evidence points to significant hazards associated with various types and use-strategies for intravenous fluids. Like other drugs, intravenous fluids should be used with caution for specific indications, in specific amounts, and with careful attention to potential adverse effects associated with various products. An individualized approach to perioperative fluid therapy is recommended.

Transcutaneous cervical vagus nerve stimulation improved motor cortex excitability in healthy adults: a randomized, single-blind, self-crossover design study.

Purpose: To investigate the effect of transcutaneous cervical vagus nerve stimulation (tcVNS) on motor cortex excitability in healthy adults. Method: Twenty eight healthy subjects were assigned to receive real and sham tcVNS for 30 min. The interval between the real and sham conditions was more than 24 h, and the sequence was random. The central and peripheral motor-evoked potential (MEP) of the right first dorsal interosseous (FDI) muscle was measured by transcranial magnetic stimulation (TMS) before and after stimulation. MEP latency, MEP amplitude and rest motor threshold (rMT) were analyzed before and after stimulation. Results: MEP amplitude, MEP latency and rMT had significant interaction effect between time points and conditions (p < 0.05). After real stimulation, the MEP amplitude was significantly increased (p < 0.001). MEP latency (p < 0.001) and rMT (p = 0.006) was decreased than that of baseline. The MEP amplitude on real condition was higher than that of sham stimulation after stimulation (p = 0.027). The latency after the real stimulation was significantly shorter than that after sham stimulation (p = 0.005). No significantly difference was found in rMT after stimulation between real and sham conditions (p > 0.05). Conclusion: tcVNS could improve motor cortex excitability in healthy adults.

Acute removal of common sepsis mediators does not explain the effects of extracorporeal blood purification in experimental sepsis.

The effect of extracorporeal blood purification on clinical outcomes in sepsis is assumed to be related to modulation of plasma cytokine concentrations. To test this hypothesis directly, we treated rats that had a cecal ligation followed by puncture (a standard model of sepsis) with a modest dose of extracorporeal blood purification that did not result in acute changes in a panel of common cytokines associated with inflammation (TNF-α, IL-1ß, IL-6, and IL-10). Pre- and immediate post-treatment levels of these cytokines were unchanged compared to the sham therapy of extracorporeal circulation without blood purifying sorbent. The overall survival to 7 days, however, was significantly better in animals that received extracorporeal blood purification compared to those with a sham procedure. This panel of common plasma cytokines along with alanine aminotransferase and creatinine was significantly lower 72 h following extracorporeal blood purification compared to sham-treated rats. Thus, the effects of this procedure on organ function and survival do not appear to be due solely to immediate changes in the usual measured circulating cytokines. These results may have important implications for the design and conduct of future trials in sepsis including defining alternative targets for extracorporeal blood purification and other therapies.

Bactericidal antibiotics temporarily increase inflammation and worsen acute kidney injury in experimental sepsis.

OBJECTIVE: To explore the relationships among bactericidal antimicrobial treatment of sepsis, inflammatory response, severity of acute kidney injury, and outcomes. DESIGN: Controlled laboratory experiment. SETTING: University laboratory. INTERVENTIONS: Sepsis was induced by cecal ligation and puncture in 52 rats and was treated with either bactericidal antibiotics (ampicillin/sulbactam) or placebo (saline). Serial blood specimens were obtained after cecal ligation and puncture for serum creatinine, interleukin-6, and neutrophil gelatinase-associated lipocalin concentrations. RIFLE (Risk, Injury, Failure, Loss, End-stage kidney disease) criteria were used to assess severity of acute kidney injury. All animals were observed for survival up to 1 wk. In a separate experiment, six healthy animals were given antibiotics and renal function was assessed. Another 12 animals were euthanized 2 days after laparotomy for kidney histology. MEASUREMENTS AND MAIN RESULTS: Survival in the placebo group was 50% compared with 81.8% in the antibiotic group (p < .05). Most animals (93%) without antibiotics developed acute kidney injury, of which 39% exhibited greater than a threefold rise in serum creatinine (RIFLE-F). Furthermore, survival decreased as acute kidney injury severity increased. Surprisingly, all antibiotic-treated animals developed acute kidney injury, of which 68.6% reached RIFLE-F. However, renal dysfunction was less persistent in these animals. Patterns of plasma interleukin-6 were similar to creatinine with higher concentrations seen earlier in antibiotic-treated animals but with faster resolution. Interleukin-6 concentration at 24 hrs was independently associated with the development of RIFLE-F. Histologic findings were consistent with functional parameters showing that antibiotics worsened acute kidney injury. CONCLUSION: In polymicrobial sepsis, bactericidal antibiotics resulted in more inflammation and more severe acute kidney injury. However, resolution of inflammation and acute kidney injury was faster with antibiotics and correlated best with survival. These results suggest that transient worsening of renal function may be an expected consequence of sepsis therapy. These findings also question the value of peak severity of acute kidney injury as a primary end point and suggest that resolution of acute kidney injury may be more appropriate.

Low-intensity transcranial ultrasound stimulation facilitates hand motor function and cortical excitability: A crossover, randomized, double blind study.

Objective: Transcranial ultrasound stimulation (TUS) is a new form of non-invasive brain stimulation. Low-intensity TUS is considered highly safe. We aimed to investigate the effect of low-intensity TUS on hand reaction responses and cortical excitability in healthy adults. Methods: This study used a crossover, randomized, and double-blind design. A total of 20 healthy participants were recruited for the study. All the participants received TUS and sham stimulation on separate days in random order. The finger tapping test (tapping score by using a tablet) and motor evoked potential (MEP) were assessed before and after stimulation, and discomfort levels were assessed using a visual analog scale (VAS) score. Results: No significant differences in tapping score or MEP amplitude between the two experimental conditions were registered before stimulation. After stimulation, tapping scores were increased regardless of the specific treatment, and the real stimulation condition receiving TUS (90.4 ± 11.0 points) outperformed the sham stimulation condition (86.1 ± 8.4 points) (p = 0.002). The MEP latency of real TUS (21.85 ± 1.33 ms) was shorter than that of sham TUS (22.42 ± 1.43 ms) (p < 0.001). MEP amplitude of real TUS (132.18 ± 23.28 µV) was higher than that of sham TUS (114.74 ± 25.5 µV, p = 0.005). There was no significant difference in the discomfort score between the two conditions (p = 0.163). Conclusion: Transcranial ultrasound stimulation (TUS) can decrease the hand reaction response time and latency of the MEP, enhance the excitability of the motor cortex, and improve hand motor function in healthy individuals without obvious discomfort.

N-acetylcysteine is effective for prevention but not for treatment of folic acid-induced acute kidney injury in mice.

OBJECTIVES: There is controversy regarding the benefits of N-acetylcysteine in acute kidney injury. This study was to compare three commonly used regimens and explore which regimen is best for the protection of acute kidney injury. DESIGN: Prospective experimental study. SETTING: University research laboratory. INTERVENTIONS: Acute kidney injury was induced with folic acid intraperitoneal injection in mice. Mice in pretreatment were treated with a subcutaneous injection of N-acetylcysteine before the folic acid injection. Mice in posttreatment were treated with N-acetylcysteine after folic acid. Mice in pre- + posttreatment were treated with N-acetylcysteine before folic acid and after folic acid. Placebo mice received vehicle only using the pre- + posttreatment protocol. Fourteen healthy animals were given N-acetylcysteine to evaluate for toxicity and the other 24 mice subjected to folic acid were killed for kidney histology and analysis for oxidative injury. The same studies were also carried out in milder acute kidney injury (lower folic acid) model. MEASUREMENTS AND MAIN RESULTS: Plasma concentrations of creatinine, cystatin C, and reduced glutathione were measured. Survival time was assessed up to 7 days. The survival rates in N-acetylcysteine pretreatment mice were significantly better (73.33% vs. 46.67%, p < .04) and acute kidney injury was significantly less compared with placebo. However, mice with posttreatment exhibited significantly worse survival and more severe acute kidney injury. Histologic findings were consistent with functional parameters. Glutathione levels decreased less in N-acetylcysteine pretreatment but also increased beginning on day 2 compared with placebo (11.5 vs. 8.1 µg/mL, p < .05). Glutathione levels did not increase in N-acetylcysteine posttreatment. However, three different N-acetylcysteine interventions neither significantly improved nor worsened renal function in the milder acute kidney injury model. CONCLUSION: N-acetylcysteine pretreatment was effective in reducing the incidence and severity of acute kidney injury as well as in increasing survival. However, N-acetylcysteine posttreatment worsened folic acid toxicity. Only pretreatment was effective in increasing glutathione. These data may help explain the variation from clinical studies of N-acetylcysteine use.

Retrospective Study of Critically Ill COVID-19 Patients With and Without Extracorporeal Membrane Oxygenation Support in Wuhan, China.

Background: Extracorporeal membrane oxygenation (ECMO) might benefit critically ill COVID-19 patients. But the considerations besides indications guiding ECMO initiation under extreme pressure during the COVID-19 epidemic was not clear. We aimed to analyze the clinical characteristics and in-hospital mortality of severe critically ill COVID-19 patients supported with ECMO and without ECMO, exploring potential parameters for guiding the initiation during the COVID-19 epidemic. Methods: Observational cohort study of all the critically ill patients indicated for ECMO support from January 1 to May 1, 2020, in all 62 authorized hospitals in Wuhan, China. Results: Among the 168 patients enrolled, 74 patients actually received ECMO support and 94 not were analyzed. The in-hospital mortality of the ECMO supported patients was significantly lower than non-ECMO ones (71.6 vs. 85.1%, P = 0.033), but the role of ECMO was affected by patients' age (Logistic regression OR 0.62, P = 0.24). As for the ECMO patients, the median age was 58 (47-66) years old and 62.2% (46/74) were male. The 28-day, 60-day, and 90-day mortality of these ECMO supported patients were 32.4, 68.9, and 74.3% respectively. Patients survived to discharge were younger (49 vs. 62 years, P = 0.042), demonstrated higher lymphocyte count (886 vs. 638 cells/uL, P = 0.022), and better CO2 removal (PaCO2 immediately after ECMO initiation 39.7 vs. 46.9 mmHg, P = 0.041). Age was an independent risk factor for in-hospital mortality of the ECMO supported patients, and a cutoff age of 51 years enabled prediction of in-hospital mortality with a sensitivity of 84.3% and specificity of 55%. The surviving ECMO supported patients had longer ICU and hospital stays (26 vs. 18 days, P = 0.018; 49 vs. 29 days, P = 0.001 respectively), and ECMO procedure was widely carried out after the supplement of medical resources after February 15 (67.6%, 50/74). Conclusions: ECMO might be a benefit for severe critically ill COVID-19 patients at the early stage of epidemic, although the in-hospital mortality was still high. To initiate ECMO therapy under tremendous pressure, patients' age, lymphocyte count, and adequacy of medical resources should be fully considered.

The influence of macrophage migration inhibitory factor gene polymorphisms on outcome from community-acquired pneumonia.

The cytokine, macrophage migration inhibitory factor (MIF), is encoded in a functionally polymorphic locus and subjects with high-expression MIF alleles are at an increased risk of inflammatory disease. Severe sepsis is the leading cause of death in intensive care units, and the prevailing hypothesis is that an excessive innate response contributes to its pathogenesis. To assess if MIF alleles influence the clinical course of infection, we conducted a case-control study to assess susceptibility and a parallel inception cohort study of community-acquired pneumonia (CAP) to assess risk of severe sepsis and 90-d mortality. Two distinct polymorphisms in the MIF promoter were analyzed: a G/C transition at -173 and a CATT repeat at -794. The frequency of both polymorphisms was similar in the CAP cohort (n=1739) and controls (n=639); however, the 90-d mortality was lower for the high-expression C allele (P=0.003). This association remained significant after adjusting for demographics, comorbid conditions, and disease severity score [hazard ratio=0.64 (0.44-0.91), P=0.01]. The hazard ratio was similar in different geographic subcohorts, and the association remained significant after adjusting for false discovery. These data indicate that polymorphisms associated with higher MIF expression may have a beneficial effect in community-acquired pneumonia.

Correction: Exosomal miR-25-3p from mesenchymal stem cells alleviates myocardial infarction by targeting proapoptotic proteins and EZH2.

Since online publication of this article, the authors noticed that an incorrect image was used during the compilation of Fig. 2a, which was caused during manuscript preparation. The correct Fig. 2a is shown below.

Exosomal miR-25-3p from mesenchymal stem cells alleviates myocardial infarction by targeting pro-apoptotic proteins and EZH2.

Mesenchymal stem cell (MSC) therapy is a promising approach against myocardial infarction (MI). Studies have demonstrated that MSCs can communicate with other cells by secreting exosomes. In the present study, we aimed to identify exosomal microRNAs that might contribute to MSC-mediated cardioprotective effects. Primary cardiomyocytes were deprived of oxygen and glucose to mimic MI in vitro. For the animal model of MI, the left anterior descending artery was ligated for 1 h, followed by reperfusion for 12 h. MSC-derived exosomes were used to treat primary cardiomyocytes or mice. Cardioprotection-related microRNAs were determined, followed by target gene identification and functional studies with quantitative PCR, western blotting, MTT assay, flow cytometry assay, chromatin immunoprecipitation and dual-luciferase assay. We found that MSC co-culture reduced OGD-induced cardiomyocyte apoptosis and inflammatory responses. Cardioprotection was also observed upon treatment with MSC-derived exosomes in vitro and in vivo. In line with this, exosome uptake led to a significant increase in miR-25-3p in cardiomyocytes. Depletion of miR-25-3p in MSCs abolished the protective effects of exosomes. Mechanistically, miR-25-3p directly targeted the pro-apoptotic genes FASL and PTEN and reduced their protein levels. Moreover, miR-25-3p decreased the levels of EZH2 and H3K27me3, leading to derepression of the cardioprotective gene eNOS as well as the anti-inflammatory gene SOCS3. Inhibition of EZH2 or overexpression of miR-25-3p in cardiomyocytes was sufficient to confer cardioprotective effects in vitro and in vivo. We concluded that exosomal miR-25-3p from MSCs alleviated MI by targeting pro-apoptotic proteins and EZH2.