Aberrant wound-healing responses to injury have been implicated in the development of pulmonary fibrosis, but the mediators directing these pathologic responses have yet to be fully identified. We show that lysophosphatidic acid levels increase in bronchoalveolar lavage fluid following lung injury in the bleomycin model of pulmonary fibrosis, and that mice lacking one of its receptors, LPA1, are markedly protected from fibrosis and mortality in this model. The absence of LPA1 led to reduced fibroblast recruitment and vascular leak, two responses that may be excessive when injury leads to fibrosis rather than to repair, whereas leukocyte recruitment was preserved during the first week after injury. In persons with idiopathic pulmonary fibrosis, lysophosphatidic acid levels in bronchoalveolar lavage fluid were also increased, and inhibition of LPA1 markedly reduced fibroblast responses to the chemotactic activity of this fluid. LPA1 therefore represents a new therapeutic target for diseases in which aberrant responses to injury contribute to fibrosis, such as idiopathic pulmonary fibrosis.

Pulmonary fibrosis is an enigmatic and devastating disease with few treatment options, now thought to result from abnormal wound healing in the lung in response to injury. We have previously noted a role for the chemokine interferon gamma-inducible protein of 10 kD (IP-10)/CXC chemokine ligand 10 in the regulation of cutaneous wound healing, and consequently investigated whether IP-10 regulates pulmonary fibrosis. We found that IP-10 is highly expressed in a mouse model of pulmonary fibrosis induced by bleomycin. IP-10-deficient mice exhibited increased pulmonary fibrosis after administration of bleomycin, suggesting that IP-10 limits the development of fibrosis in this model. Substantial fibroblast chemoattractant and proliferative activities were generated in the lung after bleomycin exposure. IP-10 significantly inhibited fibroblast responses to the chemotactic, but not the proliferative activity generated, suggesting that IP-10 may attenuate fibroblast accumulation in bleomycin-induced pulmonary fibrosis by limiting fibroblast migration. Consistent with this inhibitory activity of IP-10 on fibroblast migration, fibroblast accumulation in the lung after bleomycin exposure was dramatically increased in IP-10-deficient mice compared with wild-type mice. Conversely, transgenic mice overexpressing IP-10 were protected from mortality after bleomycin exposure, and demonstrated decreased fibroblast accumulation in the lung after challenge compared with wild-type mice. Our findings suggest that interruption of fibroblast recruitment may represent a novel therapeutic strategy for pulmonary fibrosis, which could have applicability to a wide range of fibrotic illnesses.

Supplementation of cultured human pulmonary arterial endothelial cells (PAEC) with sn-1-O-hexadecylglycerol (HG) resulted in an approximately twofold increase in cellular levels of plasmalogens, a subclass of phospholipids known to have antioxidant properties; this was due, primarily, to a fourfold increase in the choline plasmalogens. Exposure of unsupplemented human PAEC to hypoxia (PO(2) = 20-25 mmHg) caused an increase in cellular reactive oxygen species (ROS) over a period of 5 days with a coincident decrease in viability. In contrast, HG-supplemented cells survived for at least 2 wk under these conditions with no evidence of increased ROS. Hypoxia resulted in a selective increase in the turnover of the plasmalogen plasmenylethanolamine. Human PAEC with elevated plasmalogen levels were also more resistant to H(2)O(2), hyperoxia, and the superoxide generator plumbagin. This protection was seemingly specific to cellular stresses in which significant ROS were generated because the sensitivity to lethal heat shock or glucose deprivation was not altered in HG-treated human PAEC. HG, by itself, was not sufficient for protection; HG supplementation of bovine PAEC had no effect upon plasmalogen levels and did not rescue these cells from the cytotoxic effects of hypoxia. This is the initial demonstration that plasmalogen content can be substantially enhanced in a normal cell. These data also demonstrate that HG can protect cells during hypoxia and other ROS-mediated stress, likely due to the resulting increase in these antioxidant phospholipids.

Rationale. The impact of emergency department length of stay (EDLOS) upon sepsis outcomes needs clarification. We sought to better understand the relationship between EDLOS and both outcomes and protocol compliance in sepsis. Methods. We performed a retrospective observational study of septic patients admitted to the ICU from the ED between January 2012 and December 2015 in a single tertiary care teaching hospital. 287 patients with severe sepsis and septic shock were included. Study population was divided into patients with EDLOS < 6 hrs (early admission) versus ≥6 hours (delayed admission). We assessed the impact of EDLOS on hospital mortality, compliance with sepsis protocol, and resuscitation. Statistical significance was determined by chi-square test. Results. Of the 287 septic ED patients, 137 (47%) were admitted to the ICU in <6 hours. There was no significant in-hospital mortality difference between early and delayed admissions (p = 0.68). Both groups have similar compliance with the 3-hour protocol (p = 0.77). There was no significant difference in achieving optimal resuscitation within 12 hours (p = 0.35). Conclusion. We found that clinical outcomes were not significantly different between early and delayed ICU admissions. Additionally, EDLOS did not impact compliance with the sepsis protocol with the exception of repeat lactate draw.

ImportanceThere is a major need for effective, well-tolerated treatments for idiopathic pulmonary fibrosis (IPF).ObjectiveTo assess the efficacy and safety of the autotaxin inhibitor ziritaxestat in patients with IPF.Design, Setting, and ParticipantsThe 2 identically designed, phase 3, randomized clinical trials, ISABELA 1 and ISABELA 2, were conducted in Africa, Asia-Pacific region, Europe, Latin America, the Middle East, and North America (26 countries). A total of 1306 patients with IPF were randomized (525 patients at 106 sites in ISABELA 1 and 781 patients at 121 sites in ISABELA 2). Enrollment began in November 2018 in both trials and follow-up was completed early due to study termination on April 12, 2021, for ISABELA 1 and on March 30, 2021, for ISABELA 2.InterventionsPatients were randomized 1:1:1 to receive 600 mg of oral ziritaxestat, 200 mg of ziritaxestat, or placebo once daily in addition to local standard of care (pirfenidone, nintedanib, or neither) for at least 52 weeks.Main Outcomes and MeasuresThe primary outcome was the annual rate of decline for forced vital capacity (FVC) at week 52. The key secondary outcomes were disease progression, time to first respiratory-related hospitalization, and change from baseline in St George’s Respiratory Questionnaire total score (range, 0 to 100; higher scores indicate poorer health-related quality of life).ResultsAt the time of study termination, 525 patients were randomized in ISABELA 1 and 781 patients in ISABELA 2 (mean age: 70.0 [SD, 7.2] years in ISABELA 1 and 69.8 [SD, 7.1] years in ISABELA 2; male: 82.4% and 81.2%, respectively). The trials were terminated early after an independent data and safety monitoring committee concluded that the benefit to risk profile of ziritaxestat no longer supported their continuation. Ziritaxestat did not improve the annual rate of FVC decline vs placebo in either study. In ISABELA 1, the least-squares mean annual rate of FVC decline was –124.6 mL (95% CI, −178.0 to −71.2 mL) with 600 mg of ziritaxestat vs –147.3 mL (95% CI, −199.8 to −94.7 mL) with placebo (between-group difference, 22.7 mL [95% CI, −52.3 to 97.6 mL]), and –173.9 mL (95% CI, −225.7 to −122.2 mL) with 200 mg of ziritaxestat (between-group difference vs placebo, −26.7 mL [95% CI, −100.5 to 47.1 mL]). In ISABELA 2, the least-squares mean annual rate of FVC decline was –173.8 mL (95% CI, −209.2 to −138.4 mL) with 600 mg of ziritaxestat vs –176.6 mL (95% CI, −211.4 to −141.8 mL) with placebo (between-group difference, 2.8 mL [95% CI, −46.9 to 52.4 mL]) and –174.9 mL (95% CI, −209.5 to −140.2 mL) with 200 mg of ziritaxestat (between-group difference vs placebo, 1.7 mL [95% CI, −47.4 to 50.8 mL]). There was no benefit with ziritaxestat vs placebo for the key secondary outcomes. In ISABELA 1, all-cause mortality was 8.0% with 600 mg of ziritaxestat, 4.6% with 200 mg of ziritaxestat, and 6.3% with placebo; in ISABELA 2, it was 9.3% with 600 mg of ziritaxestat, 8.5% with 200 mg of ziritaxestat, and 4.7% with placebo.Conclusions and RelevanceZiritaxestat did not improve clinical outcomes compared with placebo in patients with IPF receiving standard of care treatment with pirfenidone or nintedanib or in those not receiving standard of care treatment.Trial RegistrationClinicalTrials.gov Identifiers: NCT03711162 and NCT03733444

Background Management of patients with interstitial lung disease (ILD) requires subspecialized, comprehensive, multidisciplinary care. The Pulmonary Fibrosis Foundation established the Care Center Network (CCN) in 2013 with identified criteria to become a designated CCN site. Despite these criteria, the essential components of an ILD clinic remain unknown. Research Questions How are ILD clinics within the CCN structured? What are the essential components of an ILD clinic according to ILD physician experts, patients, and caregivers? Study Design and Methods This study had 3 components. First, all 68 CCN sites were surveyed to determine the characteristics of their current ILD clinics. Second, an online, three-round modified Delphi survey was conducted between October and December 2019 with 48 ILD experts participating in total. Items for round one were generated using expert interviews. During rounds 1 and 2, experts rated the importance of each item on a 5-point Likert scale. The a priori threshold for consensus was greater than 75% of experts rating an item as important or very important. In round 3, experts graded items that met consensus and ranked items deemed essential for an ILD clinic. Third, ILD patient and caregiver focus groups were conducted and analyzed for content to determine their perspectives of an ideal ILD clinic. Results Forty items across four categories (members, infrastructure, resources and multidisciplinary conference) achieved consensus as essential to an ILD clinic. Patient and caregiver focus groups identified three major themes: comprehensive, patient-centered medical care; expanded access to care; and comprehensive support for living and coping with ILD. Interpretation The essential components of an ILD clinic are well-aligned between physician experts and patients. Future research can use these findings to evaluate the impact of these components on patient outcomes and inform best-practices for ILD clinics throughout the world.

PurposeAlcohol withdrawal syndrome (AWS) is commonly treated in medical ICUs and typically requires high resource utilization. Dexmedetomidine for AWS has not been extensively investigated, and guidelines regarding its use are lacking. We evaluated the association between dexmedetomidine use in AWS and ICU length of stay (LOS).MethodsWe performed a multi-institutional retrospective cohort study of patients in the ICU with the primary diagnosis of AWS. ICU LOS of those treated with benzodiazepines alone vs. benzodiazepines plus dexmedetomidine was compared. Negative binomial regression was performed to test whether dexmedetomidine use was associated with increased ICU LOS after adjustment for age, gender, body mass index, and the time between hospital and ICU admission.ResultsFour hundred thirty-eight patients from eight institutions were included. Patients treated with benzodiazepines plus dexmedetomidine had higher Clinical Institute Withdrawal Assessment for Alcohol scores at ICU admission, spent longer on the medical wards prior to ICU admission, and had longer unadjusted ICU LOS (p < 0.0001). After covariate adjustment, dexmedetomidine remained associated with longer ICU LOS (relative mean to non-dexmedetomidine group 2.14, 95% CI 1.78–2.57, p < 0.0001).ConclusionsCompared to benzodiazepines alone, dexmedetomidine for the treatment of AWS was associated with increased ICU LOS. These results provide evidence that dexmedetomidine may increase resource utilization.

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