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Low rates of bystander cardiopulmonary resuscitation (CPR) were identified as a shortcoming in the “chain of survival” for out-of-hospital cardiac arrest (OHCA) care in the Korean city of Ansan. This study sought to evaluate the effect of an initiative to increase bystander CPR and quality of out-of-hospital resuscitation on outcome from OHCA. The post-intervention data were used to determine the next quality improvement (QI) target as part of the “Plan-Do-Study-Act” (PDSA) model for QI.
The study hypothesis was that bystander CPR, return of spontaneous circulation (ROSC), and survival to discharge after OHCA would increase in the post-intervention period.
This was a retrospective pre/post study. The data from the pre-intervention period were abstracted from 2008–2011 and the post-intervention period from 2012–2013. The effect of the intervention on the odds of ROSC and survival to hospital discharge was determined using a generalized estimating equation to account for confounders and the effect of clustering within medical centers. The analysis was then used to identify other factors associated with outcomes to determine the next targets for intervention in the chain of survival for cardiac arrest in this community.
Rates of documented bystander CPR increased from 13% in the pre-intervention period to 37% in the post-intervention period. The overall rate of ROSC decreased from 18.4% to 14.3% (risk difference −4.1%; 95% CI, −7.1%–1.0%), whereas survival to hospital discharge increased from 3.9% to 5.0% (risk difference 1.1%; 95% CI, −1.8%–3.8%), and survival with good neurologic outcome increased from 0.8% to 1.6% (risk difference 0.8%; 95% CI, −0.8%–2.4%). In multivariable analyses, there was no association between the intervention and the rate of ROSC or survival to hospital discharge. The designated level of the treating hospital was a significant predictor of both survival and ROSC.
In this case study, there were no observed improvements in outcomes from OHCA after the targeted intervention to improve out-of-hospital CPR. However, utilizing the PDSA model for QI, the designated level of the treating hospital was found to be a significant predictor of survival in the post-period, identifying the next target for intervention.
Given its diverse disease courses and symptom presentations, multiple phenotype dimensions with different biological underpinnings are expected with bipolar disorders (BPs). In this study, we aimed to identify lifetime BP psychopathology dimensions. We also explored the differing associations with bipolar I (BP-I) and bipolar II (BP-II) disorders.
We included a total of 307 subjects with BPs in the analysis. For the factor analysis, we chose six variables related to clinical courses, 29 indicators covering lifetime symptoms of mood episodes, and 6 specific comorbid conditions. To determine the relationships among the identified phenotypic dimensions and their effects on differentiating BP subtypes, we applied structural equation modeling.
We selected a six-factor solution through scree plot, Velicer's minimum average partial test, and face validity evaluations; the six factors were cyclicity, depression, atypical vegetative symptoms, elation, psychotic/irritable mania, and comorbidity. In the path analysis, five factors excluding atypical vegetative symptoms were associated with one another. Cyclicity, depression, and comorbidity had positive associations, and they correlated negatively with psychotic/irritable mania; elation showed positive correlations with cyclicity and psychotic/irritable mania. Depression, cyclicity, and comorbidity were stronger in BP-II than in BP-I, and they contributed significantly to the distinction between the two disorders.
We identified six phenotype dimensions; in addition to symptom features of manic and depressive episodes, various comorbidities and high cyclicity constructed separate dimensions. Except for atypical vegetative symptoms, all factors showed a complex interdependency and played roles in discriminating BP-II from BP-I.
Clonorchis sinensis (C. sinensis), a trematode parasite that invades the hypoxic hepatobiliary tract of vertebrate hosts requires a considerable amount of oxygen for its sexual reproduction and energy metabolism. However, little is known regarding the molecular mechanism of C. sinensis involved in the adaptation to the hypoxic environments. In this study, we investigated the molecular structures and induction patterns of hypoxia-inducible factor-1α (HIF-1α) and other basic helix–loop–helix and Per–Arnt–Sim (bHLH–PAS) domain-containing proteins such as HIF-1β, single-minded protein and aryl hydrocarbon receptor, which might prompt adaptive response to hypoxia, in C. sinensis. These proteins possessed various bHLH–PAS family-specific domains. Expression of C. sinensis HIF-1α (CsHIF-1α) was highly induced in worms which were either exposed to a hypoxic condition or co-incubated with human cholangiocytes. In addition to oxygen, nitric oxide and nitrite affected the CsHIF-1α expression depending on the surrounding oxygen concentration. Treatment using a prolyl hydroxylase-domain protein inhibitor under 20%-oxygen condition resulted in an increase in the CsHIF-1α level. Conversely, the other bHLH–PAS genes were less responsive to these exogenous stimuli. We suggest that nitrite and nitric oxide, as well as oxygen, coordinately involve in the regulation of HIF-1α expression to adapt to the hypoxic host environments in C. sinensis.
Bloodstream infection (BSI) occurred in 21 of 121 patients (17%) receiving venovenous extracorporeal membrane oxygenation within the median time of 6 days after initiation (interquartile range, 4–19 days). Longer duration of arterial catheterization and more blood transfusions were independently associated with BSI, which is associated with poor clinical outcomes.
To evaluate the appropriateness of the screening strategy for healthcare personnel (HCP) during a hospital-associated Middle East Respiratory Syndrome (MERS) outbreak, we performed a serologic investigation in 189 rRT-PCR–negative HCP exposed and assigned to MERS patients. Although 20%–25% of HCP experienced MERS-like symptoms, none of them showed seroconversion by plaque reduction neutralization test (PRNT).
In interpreting radiocarbon dating results, it is important that archaeologists distinguish uncertainties derived from random errors and those from systematic errors, because the two must be dealt with in different ways. One of the problems that archaeologists face in practice, however, is that when receiving dating results from laboratories, they are rarely able to critically assess whether differences between multiple 14C dates of materials are caused by random or systematic errors. In this study, blind tests were carried out to check four possible sources of errors in dating results: repeatability of results generated under identical field and laboratory conditions, differences in results generated from the same sample given to the same laboratory submitted at different times, interlaboratory differences of results generated from the same sample, and differences in the results generated between inner and outer rings of wood. Five charred wood samples, collected from the Namgye settlement and Hongreyonbong fortress, South Korea, were divided into 80 subsamples and submitted to five internationally recognized 14C laboratories on a blind basis twice within a 2-month interval. The results are generally in good statistical accordance and present acceptable errors at an archaeological scale. However, one laboratory showed a statistically significant variance in ages between batches for all samples and sites. Calculation of the Bayesian partial posterior predictive p value and chi-squared tests rejected the null hypothesis that the errors randomly occurred, although the source of the error is not specifically known. Our experiment suggests that it is necessary for users of 14C dating to establish an organized strategy for dating sites before submitting samples to laboratories in order to avoid possible systematic errors.
A trend toward greater body size in dizygotic (DZ) than in monozygotic (MZ) twins has been suggested by some but not all studies, and this difference may also vary by age. We analyzed zygosity differences in mean values and variances of height and body mass index (BMI) among male and female twins from infancy to old age. Data were derived from an international database of 54 twin cohorts participating in the COllaborative project of Development of Anthropometrical measures in Twins (CODATwins), and included 842,951 height and BMI measurements from twins aged 1 to 102 years. The results showed that DZ twins were consistently taller than MZ twins, with differences of up to 2.0 cm in childhood and adolescence and up to 0.9 cm in adulthood. Similarly, a greater mean BMI of up to 0.3 kg/m2 in childhood and adolescence and up to 0.2 kg/m2 in adulthood was observed in DZ twins, although the pattern was less consistent. DZ twins presented up to 1.7% greater height and 1.9% greater BMI than MZ twins; these percentage differences were largest in middle and late childhood and decreased with age in both sexes. The variance of height was similar in MZ and DZ twins at most ages. In contrast, the variance of BMI was significantly higher in DZ than in MZ twins, particularly in childhood. In conclusion, DZ twins were generally taller and had greater BMI than MZ twins, but the differences decreased with age in both sexes.
Despite recent reports regarding the biology of cytosine methylation in Schistosoma mansoni, the impact of the regulatory machinery remains unclear in diverse platyhelminthes. This ambiguity is reinforced by discoveries of DNA methyltransferase 2 (DNMT2)-only organisms and the substrate specificity of DNMT2 preferential to RNA molecules. Here, we characterized a novel DNA methyltransferase, named CsDNMT2, in a liver fluke Clonorchis sinensis. The protein exhibited structural properties conserved in other members of the DNMT2 family. The native and recombinant CsDNMT2 exhibited considerable enzymatic activity on DNA. The spatiotemporal expression of CsDNMT2 mirrored that of 5-methylcytosine (5 mC), both of which were elevated in the C. sinensis eggs. However, CsDNMT2 and 5 mC were marginally detected in other histological regions of C. sinensis adults including ovaries and seminal receptacle. The methylation site seemed not related to genomic loci occupied by progenies of an active long-terminal-repeat retrotransposon. Taken together, our data strongly suggest that C. sinensis has preserved the functional DNA methylation machinery and that DNMT2 acts as a genuine alternative to DNMT1/DNMT3 to methylate DNA in the DNMT2-only organism. The epigenetic regulation would target functional genes primarily involved in the formation and/or maturation of eggs, rather than retrotransposons.
Si delta-doping in the GaN layer has been successfully demonstrated by low-pressure metalorganic chemical vapor deposition at a growth temperature of 1040 . Si delta-doping concentration increases and then decreases with an increase in delta-doping time. This indicates that delta-doping concentration is limited by the desorption process owing to much higher thermal decomposition efficiency of silane at high growth temperatures of GaN. In addition, it was observed that the use of a post-purge step in the ammonia ambient reduces Si delta-doping concentration. From capacitance-voltage measurement, a sharp carrier concentration profile with a full-width at half maximum of 4.1 nm has been achieved with a high peak concentration of 9.8 1018 cm−3.
To investigate whether low vitamin D status was related to insulin resistance (IR) or impaired fasting glucose (IFG) in Korean adolescents, after adjusting for total body fat mass (FM).
A cross-sectional study.
Korea National Health and Nutrition Examination Survey (KNAHNES) 2009–2010.
In total, 1466 participants (769 males) aged 10–19 years were assessed for serum 25-hydroxyvitamin D (25(OH)D) levels, for FM by whole-body dual-energy X-ray absorptiometry and for IR by homeostasis model assessment (HOMA-IR) after an 8 h fast.
Age-, sex-, season- and physical-activity-adjusted regression models showed that serum 25(OH)D levels were significantly related to markers of adiposity (P = 0·016 for FM (g), P = 0·023 for FM (%) and P = 0·035 for fat mass index). When the participants were stratified into three 25(OH)D categories (<37·5 nmol/l (n 553), 37·5 to < 50 nmol/l (n 543) and ≥ 50 nmol/l (n 370)), significantly decreasing trends were observed for fasting insulin (all P < 0·001), HOMA-IR (all P < 0·001) and the odds ratios for IFG (all P for trend < 0·05) from the lowest to the highest 25(OH)D category, after adjustments for age, sex, physical activity and all markers of adiposity. In the multivariate logistic regression analysis, the likelihood of participants in the lowest serum 25(OH)D category having IFG was 2·96–3·15 compared with those in the highest 25(OH)D category (all P < 0·05).
There was a significant inverse relationship between vitamin D status and IR and the risk of IFG, independent of adiposity, in Korean adolescents.
The in vitro corrosion mechanism of the biodegradable cast Mg–10% Ca binary alloy in Hanks' solution was evaluated through transmission electron microscopy observations. The corrosion behavior depends strongly on the microstructural peculiarity of Mg2Ca phase surrounding the island-like primary Mg phase and the fast corrosion induced by the interdiffusion of O and Ca via the Mg2Ca phase of lamellar structure. At the corrosion front, we found that a nanosized crack-like pathway was formed along the interface between the Mg2Ca phase and the primary Mg phase. Through the crack-like pathway, O and Ca are atomically exchanged each other and then the corroded Mg2Ca phase was transformed to Mg oxides. The in vitro corrosion by the exchange of Ca and O at the nanosized pathway led to the rapid bulk corrosion in the Mg–Ca alloys.
To evaluate the prevalence of vitamin D deficiency and predictors for low vitamin D status in Korean adolescents living between latitudes 33° and 39°N.
A descriptive cross-sectional study.
Korea National Health and Nutrition Examination Survey (KNHANES) 2008–2009.
A total of 1510 healthy adolescents aged 12–18 years (806 male, mean age 14·7 years) participated. Possible predictors for low vitamin D status (log-transformed 25-hydroxyvitamin D (25(OH)D) concentrations) were evaluated.
The prevalence of vitamin D deficiency (25(OH)D<20 ng/ml) was 89·1 % in spring, 53·7 % in summer, 63·9 % in autumn and 90·5 % in winter. Winter season, older age, higher education level reached, being female, being obese, a lack of vitamin D supplementation, lower milk consumption (0–<200 ml/d) and a lack of physical activity were unadjusted predictors (all P < 0·05). Multiple linear regression analysis showed that winter season (P < 0·001), higher education level (P < 0·001) and a lack of vitamin D supplementation (P = 0·012) were independent predictors for low vitamin D status. The modifying effect of season on the association between vitamin D supplement use and vitamin D status was significant (P < 0·001).
Vitamin D deficiency was highly prevalent in Korean adolescents, especially those in higher school grades. Vitamin D supplementation may contribute to maintain a better vitamin D status with lower seasonal variation. Further studies are required to determine optimal vitamin D intakes to maintain sufficient vitamin D status for Korean adolescents.
Hydrothermally grown TiO2 nanorod (NR) photoelectrodes were prepared by sensitizing CdS quantum dots to improve visible light activity of the TiO2. The CdS-sensitized photoelectrodes were heat-treated to obtain enhanced performance of the photoelectrode under visible light. Furthermore, performance of the TiO2 NR-based photoanodes was compared with those made of TiO2 nanotubes (NTs). Photocurrent measurement and overall cell efficiency of the NR-based solar cells showed higher efficiency compared to NT-based solar cell.
Through a polyethylene-glycol-assisted hydrothermal method, a series of potassium fluoride (KF)–Yttrium (III) fluoride (YF3) system materials have been synthesized. By controlling the reactant ratios of KF: rare earth ions (RE3+), the hydrothermal temperatures, and the pH values of the prepared solutions, the final products can evolve among the orthorhombic phase of YF3 and/or the tetragonal phase of potassium triyttrium decafluoride (KY3F10) and/or the cubic phase of potassium yttrium tetrafluoride (KYF4). The final products are characterized by the x-ray diffraction (XRD) patterns, the field-emission scanning electron microscopy (FE-SEM) images, the energy-dispersive spectroscopy (EDS) patterns, the photoluminescence (PL) spectra, and the luminescent dynamic decay curves. The XRD patterns of the samples suggest the phase evolution of the final products. The FE-SEM images and the EDS patterns prove that. Europium ion (Eu3+) acting as a probe, its PL spectra and the luminescent decay curves all put together prove the phase evolution of the final products. The research can be extended to study the other KF–REF3 system materials.
Based on a citric acid-assisted hydrothermal method, series of Ce3+/Tb3+ activated fluorides have been synthesized. By controlling the amount of KNO3, the final products evolve from the Ce3+/Tb3+ codoped orthorhombic phase GdF3 to the Ce3+/Tb3+ codoped cubic phase KGdF4. The concentration of Ce3+ has great effects on the crystalline phases and the morphologies of final products. The Ce3+ concentration dependent samples illustrate the appearance of the hexagonal phase solid solution CeF3–GdF3–TbF3 in the final products. When the Ce3+ concentration is 20 mol%, the sample Ce20 presents the hexagonal phase CeF3 but the diffraction peaks move to higher degree. The x-ray diffraction patterns suggest the phase evolution of final products, the field emission scanning electron microscopy images present the variation in morphology of samples, and the photoluminescence excitation and emission spectra as well as the luminescent dynamic curves illustrate the optical properties of samples.