Annual improvement trends in resuscitation outcome of patients defibrillated by laypersons after out-of-hospital cardiac arrests and compression-only resuscitation of laypersons.

AIM: We aimed to investigate the effect of compression-only cardiopulmonary resuscitation (CPR) with conventional CPR in patients who were defibrillated by laypersons. METHODS: This is a population-based, nationwide observational study. Adult and children who sustained a witnessed out-of-hospital cardiac arrest and defibrillated by laypersons between 2005 to 2019 were identified on the national database. The study used trend analyses, multivariate logistic regression, and inverse probability weighting using propensity score to explore changes in one-month survival and survival with a good neurological outcome over time and the influence of compression-only CPR compared with conventional CPR. RESULTS: In total, 11,402 patients defibrillated by laypersons were enrolled in this study. The percentages of compression-only resuscitation increased dramatically and more than 50% from 2012 (P < 0.001). The percentages of cases with favorable resuscitation outcomes also increased annually (P < 0.001). By regression analysis, favorable outcomes were associated with recent years, male sex, younger age, and shorter resuscitation start time. In addition, the adjusted odds ratio of compression-only CPR to conventional CPR was 1.23 with a 95% confident interval 1.13-1.34. By inverse probability weighting, compression-only CPR was superior to conventional CPR for the favorable outcomes (P < 0.001). The adjusted outcomes in each year were better in compression-only resuscitation in most of the years. The overall relative risk reduction and the number needed to treat for compression-only resuscitation compared with conventional resuscitation were 7.6% and 22.1, respectively. CONCLUSIONS: In Japan, the outcomes of out-of-hospital cardiac arrest patients who were defibrillated by laypersons were considerably better in compression-only resuscitation of laypersons every year.

The activation mechanism of the aryl hydrocarbon receptor (AhR) by molecular chaperone HSP90.

The aryl hydrocarbon receptor is a member of the nuclear receptor superfamily that associates with the molecular chaperone HSP90 in the cytoplasm. The activation mechanism of the AhR is not yet fully understood. It has been proposed that after binding of ligands such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), 3methylcholanthrene (3-MC), or ß-naphthoflavone (ß-NF), the AhR dissociates from HSP90 and translocates to the nucleus. It has also been hypothesized that the AhR translocates to the nucleus and forms a complex with HSP90 and other co-chaperones. There are a few reports about the direct association or dissociation of AhR and HSP90 due to difficulties in purifying AhR. We constructed and purified the PAS domain from AhR. Binding of the AhR-PAS domain to ß-NF affinity resin suggested that it possesses ligand-binding affinity. We demonstrated that the AhR-PAS domain binds to HSP90 and the association is not affected by ligand binding. The ligand 17-DMAG inhibited binding of HSP90 to GST-PAS. In an immunoprecipitation assay, HSP90 was co-immunoprecipitated with AhR both in the presence or absence of ligand. Endogenous AhR decreased in the cytoplasm and increased in the nucleus of HeLa cells 15 min after treatment with ligand. These results suggested that the ligand-bound AhR is translocated to nucleus while in complex with HSP90. We used an in situ proximity ligation assay to confirm whether AhR was translocated to the nucleus alone or together with HSP90. HSP90 was co-localized with AhR after the nuclear translocation. It has been suggested that the ligand-bound AhR was translocated to the nucleus with HSP90. Activated AhR acts as a transcription factor, as shown by the transcription induction of the gene CYP1A1 8 h after treatment with ß-NF.

How, when, and where have rental automated external defibrillators been used in Japan?

OBJECTIVE: Automated external defibrillators (AEDs) have been rented in various places in Japan. When rental AEDs are placed in locations where the probability of sudden cardiac arrest is high and permanent placement of AEDs is difficult, the possibility of improving survival rates might increase. In this preliminary study, we investigated how, when, and where rental AEDs have been used in Japan to clarify their characteristics when used in actual situations and to facilitate better usage in the future. METHODS: We investigated the total number of AEDs rented, the duration of rental of each AED, the total number of AEDs rented monthly, the rental sites, the frequency and location of use, the number of defibrillations, and the time to defibrillation success for devices rented between January 2008 and December 2010 by a single company in Japan. RESULTS: The number of AEDs rented annually was 590 at 391 sites in 2008, 767 at 465 sites in 2009, and 847 at 477 sites in 2010. More AEDs were rented during the summer. The devices were actually used on 17 individuals, of whom 2 individuals (at a beach and a marathon) underwent defibrillation, and 1 individual (at a marathon) survived. CONCLUSION: Rental AEDs can play an important role in emergency cases occurring during seasonal and temporary outdoor events. The provision of rental AEDs in locations where permanent AEDs would be unfeasible may offer a useful strategy for efficiently improving survival rates in the future.