The ROX index (Index combining the respiratory rate with oxygenation) is a prognostic factor for acute respiratory distress syndrome.

BACKGROUND: There is no existing reliable and practical method for predicting the prognosis of acute respiratory distress syndrome (ARDS). OBJECTIVE: We aimed to clarify the association between the ROX index, which is calculated as the ratio of peripheral oxygen saturation divided by the fraction of inspired oxygen to the respiratory rate, and the prognosis of patients with ARDS under ventilator support. METHODS: In this single-center retrospective cohort study from prospectively collected database, eligible patients were categorized into three groups based on ROX tertiles. The primary outcome was the 28-day survival, and the secondary outcome was 28-day liberation from ventilator support. We performed multivariable analysis using the Cox proportional hazards model. RESULTS: Among 93 eligible patients, 24 (26%) patients died. The patients were divided into three groups according to the ROX index (< 7.4, 7.4-11, ≥ 11), with 13, 7, and 4 patients dying in the groups, respectively. A higher ROX index was associated with lower mortality; adjusted hazard ratios [95% CIs] for increasing tertiles of ROX index: 1[reference], 0.54[0.21-1.41], 0.23[0.074-0.72] (P = 0.011 for trend) and a higher rate of successful 28-day liberation from ventilator support; adjusted hazard ratios [95% CIs] for increasing tertiles of ROX index: 1[reference], 1.41[0.68-2.94], 2.80[1.42-5.52] (P = 0.001 for trend). CONCLUSIONS: The ROX index at 24 h after initiating ventilator support is a predictor of outcomes in patients with ARDS and might inform initiation of more advanced treatments.

Clinical phenotypes from fatal cases of acute respiratory distress syndrome caused by pneumonia.

There have been no report of objective clinical characteristics or prognostic factors that predict fatal outcome of acute respiratory distress syndrome (ARDS) since the Berlin definition was published. The aim of this study is to identify clinically available predictors that distinguish between two phenotypes of fatal ARDS due to pneumonia. In total, 104 cases of Japanese patients with pneumonia-induced ARDS were extracted from our prospectively collected database. Fatal cases were divided into early (< 7 days after diagnosis) and late (≥ 7 days) death groups, and clinical variables and prognostic factors were statistically evaluated. Of the 50 patients who died within 180 days, 18 (36%) and 32 (64%) were in the early (median 2 days, IQR [1, 5]) and late (median 16 days, IQR [13, 29]) death groups, respectively. According to multivariate regression analyses, the APACHE II score (HR 1.25, 95%CI 1.12-1.39, p < 0.001) and the disseminated intravascular coagulation score (HR 1.54, 95%CI 1.15-2.04, p = 0.003) were independent prognostic factors for early death. In contrast, late death was associated with high-resolution computed tomography (HRCT) score indicating early fibroproliferation (HR 1.28, 95%CI 1.13-1.42, p < 0.001) as well as the disseminated intravascular coagulation score (HR 1.24, 95%CI 1.01-1.52, p = 0.039). The extent of fibroproliferation on HRCT, and the APACHE II scores along with coagulation abnormalities, should be considered for use in predictive enrichment and personalized medicine for patients with ARDS due to pneumonia.

Generation of Cellular Reactive Oxygen Species by Activation of the EP2 Receptor Contributes to Prostaglandin E2-Induced Cytotoxicity in Motor Neuron-Like NSC-34 Cells.

Amyotrophic lateral sclerosis (ALS) is a devastating motor neuron disease characterized by progressive degeneration of motor neurons in the central nervous system. Prostaglandin E2 (PGE2) plays a pivotal role in the degeneration of motor neurons in human and transgenic models of ALS. We have shown previously that PGE2 directly induces neuronal death through activation of the E-prostanoid (EP) 2 receptor in differentiated NSC-34 cells, a motor neuron-like cell line. In the present study, to clarify the mechanisms underlying PGE2-induced neurotoxicity, we focused on generation of intracellular reactive oxygen species (ROS) and examined the effects of N-acetylcysteine (NAC), a cell-permeable antioxidant, on PGE2-induced cell death in differentiated NSC-34 cells. Dichlorofluorescein (DCF) fluorescence analysis of PGE2-treated cells showed that intracellular ROS levels increased markedly with time, and that this effect was antagonized by a selective EP2 antagonist (PF-04418948) but not a selective EP3 antagonist (L-798,106). Although an EP2-selective agonist, butaprost, mimicked the effect of PGE2, an EP1/EP3 agonist, sulprostone, transiently but significantly decreased the level of intracellular ROS in these cells. MTT reduction assay and lactate dehydrogenase release assay revealed that PGE2- and butaprost-induced cell death were each suppressed by pretreatment with NAC in a concentration-dependent manner. Western blot analysis revealed that the active form of caspase-3 was markedly increased in the PGE2- and butaprost-treated cells. These increases in caspase-3 protein expression were suppressed by pretreatment with NAC. Moreover, dibutyryl-cAMP treatment of differentiated NSC-34 cells caused intracellular ROS generation and cell death. Our data reveal the existence of a PGE2-EP2 signaling-dependent intracellular ROS generation pathway, with subsequent activation of the caspase-3 cascade, in differentiated NSC-34 cells, suggesting that PGE2 is likely a key molecule linking inflammation to oxidative stress in motor neuron-like NSC-34 cells.

Clinical characteristics of dermatomyosits/polymyositis associated interstitial lung disease according to the autoantibody.

BACKGROUND: Dermatomyositis (DM) and polymyositis (PM) often have association with interstitial lung disease (ILD) which have disease specific autoantibody. METHODOLOGY: We reviewed medical records of DM/PM associated ILD from January 2000 to December 2017 according to the autoantibody. RESULT: We identified 52 patients, of whom 30 were antibody negative, 18 had anti aminoacyl-tRNA synthetases (ARS) antibodies and 4 had anti melanoma differentiation-associated gene (MDA)-5 antibody. In high resolution computed tomography (HRCT) of the chest, area of ground glass opacity (GGO), consolidation, and lung tip consolidation were more extensive in anti MDA-5 antibody positive patients (p=0.051, p=0.026, and p=0.027, respectively). Among laboratory findings, GOT had strong correlations with CPK (r=0.889, p < 0.001), and LDH (r=0.910, p < 0.001). Among roentgenographic findings, there were moderate correlations between GGO and consolidation (r=0.668, p < 0.001), and between reticular shadow and traction bronchiectasis (p=0.633, p < 0.001). ILD patients with anti MDA-5 antibodies had decreased survival (1.00 vs 84.3, 22.9 months, p < 0.001). CONCLUSION: ILD patients with anti ARS antibody had intense inflammation, but reversible fibrosis and good prognosis. On the other hand, anti MDA-5 antibody positive ILD patients had shorter survival. Extent of parenchymal shadow and serum GOT were useful indicator of disease activity of PM/DM associated ILD patients in our cohort. J. Med. Invest. 65:251-257, August, 2018.

Characterization of Motor Neuron Prostaglandin E2 EP3 Receptor Isoform in a Mouse Model of Amyotrophic Lateral Sclerosis.

Amyotrophic lateral sclerosis (ALS) is a motor neuron disease with adult onset, characterized by progressive loss of motor neurons. Prostaglandin E2 (PGE2), a lipid mediator, exerts its biological functions by binding to four subtypes of E-prostanoid (EP1-4). Among them, EP3 has been shown to have multiple isoforms, EP3α, EP3ß, and EP3γ, produced by alternative splicing. Since PGE2 has been shown to have important pathophysiological roles in ALS, experiments were performed to identify EP3 receptor isoform(s) in spinal motor neurons of wild-type (WT) and ALS model (G93A) mice. Reverse transcription-polymerase chain reaction (RT-PCR) analysis of adult mice demonstrated expression of EP3α and EP3γ mRNAs in the lumbar spinal cord, whereas EP3ß mRNA was barely detectable. Laser capture microdissection was used to dissect out motor neurons from frozen samples of lumbar spinal cord in these mice for analysis by real-time PCR. We found that expression of EP3γ mRNA was predominant in these neurons, whereas EP3α and EP3ß mRNAs were undetectable. At the early symptomatic stage, the mRNA expression profiles of these splice isoforms in G93A motor neurons were comparable to those in neurons from WT mice. These results suggest that the PGE2-to-EP3 signaling pathway is mediated mainly by the EP3γ isoform in the motor neurons of mice, and that modulation of the EP3γ isoform in motor neurons may be a promising new therapeutic approach for ALS.