[Show abstract][Hide abstract] ABSTRACT: Stenotrophomonas maltophilia causes serious infections in immunocompromised hosts. Here, we analyzed the clinical characteristics of S. maltophilia bloodstream infection (BSI) in patients with hematologic malignancies and evaluated in vitro synergistic effects of antimicrobial combinations.
We retrospectively reviewed all consecutive episodes of S. maltophilia BSIs in adult hematologic patients from June 2009 to May 2014, with in vitro susceptibility and synergy tests using high-throughput bioluminescence assay performed for available clinical isolates.
Among 11,004 admissions during 5-year period, 31 cases were identified as S. maltophilia BSIs. The incidence rate of S. maltophilia BSI was 0.134 cases/1,000 patient-days. Overall and attributable mortality of S. maltophilia BSI was 64.5% and 38.7%, respectively. Severe neutropenia (adjusted hazard ratio [HR] 5.24, p =0.013), shock at the onset of BSI (adjusted HR 6.05, p <0.001), and pneumonia (adjusted HR 3.15, p =0.017) were independent risk factors for mortality. In vitro susceptibilities to ceftazidime, levofloxacin, ticarcillin-clavulanic acid (TIM) and trimethoprim-sulfamethoxazole (SXT) were 11.1%, 44.0%, 40.7%, and 88.9%, respectively. MIC50/MIC90 for moxifloxacin and tigecycline were 1/4 mg/L and 4/8 mg/L. The 50% and 90% fractional inhibitory concentrations (FIC(50)/FIC(90)) of clinical isolates against a combination of SXT and TIM were 0.500/0.750. For SXT plus levofloxacin or moxifloxacin, FIC(50)/FIC(90) were 0.625/1.000 and 0.625/0.625, respectively.
S. maltophilia BSIs show high mortality, which is related to severe neutropenia, shock, and S. maltophilia pneumonia. Based upon drug susceptibility testing, the primary treatment of choice for S. maltophilia BSIs should be SXT in hematologic patients, rather than quinolones, with combination therapies including SXT serving as a feasible treatment option.
[Show abstract][Hide abstract] ABSTRACT: Posaconazole was introduced as the primary antifungal prophylaxis (PAP) in acute myeloid leukaemia (AML) or myelodysplastic syndrome (MDS) patients during remission induction chemotherapy. Data on breakthrough invasive fungal infections (IFIs) from various centres are essential, as there are several considerations in treating IFIs in the posaconazole era. The aim of this study was to evaluate the effectiveness of posaconazole PAP and identify characteristics of IFIs at a single centre in Korea. We retrospectively reviewed consecutive patients with AML/MDS undergoing remission induction chemotherapy between December 2010 and November 2013. Of the 424 patients, 140 received posaconazole and 284 received fluconazole prophylaxis. The incidence of breakthrough proven/probable IFIs (15.5% vs. 2.9%, P < 0.001) and empirical antifungal treatment (EAFT) (45.8% vs. 12.9%, P < 0.001) decreased in the posaconazole group compared to the fluconazole group. In the posaconazole PAP group, two cases of breakthrough mucormycosis were noted among 13 proven/prob-able/possible IFI cases (15.4%). Overall and IFI-related mortality was 12.1% and 1.9% respectively. Fungus-free survival was significantly higher in the posaconazole group (74.7% vs. 87.1%, P = 0.028). Breakthrough IFIs and EAFT decreased significantly after posaconazole PAP. The benefit in fungus-free survival was noted with posaconazole PAP. Clinicians should be vigilant to identify non-Aspergillus IFIs with active diagnostic effort.
[Show abstract][Hide abstract] ABSTRACT: It is not well known about the implication of left ventricular (LV) strain as a predictor for mortality in patients with chronic aortic regurgitation (AR). The purpose of this study was to investigate whether global longitudinal strain measured by two-dimensional speckle-tracking echocardiography could predict long-term outcome in patients with chronic AR.
This is a single center non-randomized retrospective observational study. The patients with chronic AR from January 2002 to December 2012 were retrospectively enrolled. Following patients were excluded; combined other significant valvular disease, previous heart surgery, aortic disease, congenital heart disease, acute AR and young age under 18 years old. Finally, 60 patients were analyzed and the LV global strain rate was measured on apical four chamber image (GS-4CH).
During 64 months follow-up duration, 16 patients (26.7%) were deceased and 38 patients (63.3%) underwent aortic valve replacement (AVR). Deceased group was older (69 years old vs. 51 years old, p < 0.001) and had lower longitudinal strain (-12.05 ± 3.72% vs. -15.66 ± 4.35%, p = 0.005). Kaplan-Meier survival curve stratified by GS-4CH showed a trend of different event rate (log rank p = 0.001). On multivariate analysis by cox proportional hazard model adjusting for age, sex, body surface area, history of atrial fibrillation, blood urea nitrogen, LV dilatation, LV ejection fraction and AVR, decreased GS-4CH proved to be an independent predictor of mortality in patients with chronic AR (hazard ratio 1.313, 95% confidence interval 1.010-1.706, p = 0.042).
GS-4CH may be a useful predictor of mortality in patient with chronic AR.
Journal of cardiovascular ultrasound 06/2015; 23(2):78-85. DOI:10.4250/jcu.2015.23.2.78
[Show abstract][Hide abstract] ABSTRACT: Routine vaccination against mumps has markedly reduced its incidence. However, the incidence of mumps continuously has increased since 2007. In 2013, a large mumps epidemic occurred in Korea, and this epidemic is still an ongoing problem. This epidemic occurred primarily in school settings and affected vaccinated adolescents, predominantly male students. The recent resurgence of mumps is caused by multiple factors: suboptimal effectiveness of the current mumps vaccines, use of the Rubini strain vaccine, waning immunity in the absence of natural boosting due to the marked reduction in the mumps incidence, genotype mismatch between the vaccine and circulating mumps virus strains, and environmental conditions that foster intense exposures. Containment of mumps outbreaks is challenging because the sensitivity of diagnostic tests is low among vaccinees and control measures are less efficient because of the inherent nature of the mumps virus. Despite the suboptimal vaccine effectiveness in outbreak settings, maintaining the high vaccine coverage is an important strategy to prevent mumps outbreaks, given that the routine use of mumps vaccines has substantially reduced the incidence of mumps and its complications as compared with that in the pre-vaccine era. In order to control the current mumps epidemic and prevent further outbreaks, we need to better understand the dynamics of mumps among vaccinated populations and the changing epidemiology in Korea. Concerted efforts should be made to systematically monitor the immunization status of the Korean population and to improve diagnosis efficiency. Furthermore, more effective mumps vaccines need to be developed in the future.
[Show abstract][Hide abstract] ABSTRACT: We investigated the thermal stability of exo-tetrahydrodicyclopentadiene (exo-THDCP, C10H16) in the absence and presence of 5,6,7,8-tetrafluoro-1,2,3,4-tetrahydroquinoxaline (TFQox), a new hydrogen donor (H donor). Conversion of exo-THDCP was slowed in the presence of TFQox but less effectively compared to its analogues, 1,2,3,4-tetrahydroquinoxaline (THQox) and 1,2,3,4-tetrahydroquinoline (THQ). We analyzed the H-donor effects on the thermal decomposition kinetics of exo-THDCP, which explains the relative effect of the H donors on the thermal stability improvement of exo-THDCP.
Energy & Fuels 01/2015; 29(1):16-20. DOI:10.1021/ef5016445 · 2.79 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The pattern and prognostic impact of "early" acute kidney injury (AKI) after primary percutaneous coronary intervention (PCI) in patients with ST-segment elevation myocardial infarction have not been well established. From November 2005 to November 2011, 971 postemyocardial infarction patients who underwent primary PCI were analyzed. Early AKI was defined using absolute change in serum creatinine (SCr; SCr <24 hours after primary PCI minus admission SCr) as follows: no early AKI (SCr change <0.3 mg/dl), mild early AKI (SCr change 0.3 to <0.5 mg/dl), moderate early AKI (SCr change 0.5 to <1.0 mg/dl), and severe early AKI (SCr change ≥1.0 mg/dl). One-year major adverse cardiac events were defined as death, nonfatal myocardial infarction, and revascularizations. Overall, 9.6% had early AKI, including 5.7% with mild, 2.5% with moderate, and 1.4% with severe early AKI. Diabetes mellitus (odds ratio 1.84, p = 0.042), the left ventricular ejection fraction (odds ratio 0.97, p = 0.042), and hemoglobin levels (odds ratio 0.84, p = 0.039) were independently associated with early AKI. Early AKI (adjusted hazard ratio 2.80, p = 0.005) was an independent predictor of 1-year major adverse cardiac events. The adjusted hazard ratios of 1-year major adverse cardiac events from the lowest (reference) to the highest quartile of early AKI were as follows: 1, 2.87 (p = 0.012), 3.22 (p = 0.021), and 5.83 (p = 0.004), respectively. In conclusion, early dynamic change in renal function after primary PCI can sensitively predict worse outcomes.
European Heart Journal 10/2014; 114(8). DOI:10.1016/j.amjcard.2014.07.039 · 15.20 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Catalytic endothermic reactions of exo-tetrahydrodicyclopentadiene (exo-THDCP) with different zeolites were investigated in a batch reactor to increase the heat of reaction. The heat of reaction with each zeolite was calculated by the NIST SUPERTRAPP program. The conversion and product distribution were also investigated because they affected the heat of reaction. The heat of reaction of HZSM-5 was larger than those of other zeolite due to its total acid density and pore structures. It showed the highest conversion and highest composition of low molecular weight products. Because dehydrogenation can increase endothermic heat, Pt/HZSM-5 (1 wt% Pt loaded) was used in the endothermic reaction. The metal sites led the dehydrogenation of saturated hydrocarbons and increase in olefins. To increase the heat of reaction, high conversion and high yield of low molecular weight hydrocarbons and olefins are necessary. 2013 Elsevier By. All rights reserved.
[Show abstract][Hide abstract] ABSTRACT: BackgroundA recent genome-wide association study has identified 5-hydroxytrytamine (serotonin) receptor 7, adenylate cyclase-coupled (HTR7) as a risk gene for alcohol dependence. In addition, the serotonergic system has been considered as a modulator that plays an important role in alcohol use disorders. Functional, pharmacological, and genetic studies of serotonin neurotransmission have revealed that serotonin receptors are potential targets for the treatment of alcohol use disorders. The aim of this study is to investigate whether associations between HTR7 genetic polymorphisms and alcohol dependence could be replicated.Methods
This study genotyped a total of 22 common single nucleotide polymorphisms (SNPs) in 459 alcoholic patients and 444 nonalcoholic controls.ResultsLogistic regression analysis of the case–control study, controlling for age and sex as covariates, showed nominal associations of 7 SNPs (p = 0.02 to 0.04; odds ratio = 0.60 to 1.35). In further linear regression analysis based on the Alcohol Use Disorders Identification Test score for alcohol dependence, 8 SNPs and 3 haplotypes showed relatively significant associations with alcohol dependence (minimum p = 0.001; pcorr = 0.02).Conclusions
Although further replications and functional evaluations are needed, our findings suggest that genetic variations of HTR7 may contribute to the predisposition for alcohol dependence.
Alcoholism Clinical and Experimental Research 07/2014; 38(9). DOI:10.1111/acer.12482 · 3.21 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Objective:
Extended-spectrum β-lactamase (ESBL)-producing Escherichia coli has become an important cause of community-onset urinary tract infections. We aimed to evaluate the efficacy of non-carbapenem antibiotics for acute pyelonephritis (APN) due to ESBL-producing E. coli.
We conducted a retrospective cohort study of patients with community-onset APN due to ESBL-producing E. coli at a single centre in Korea from 2007 to 2013. Outcomes included both microbiological and clinical failure. To adjust for non-random assignment of antibiotics, the propensity score method of inverse probability of treatment weighting and a multivariable analysis using Cox proportional hazards modelling were employed to estimate the efficacy of non-carbapenem antibiotics as compared with carbapenems.
Of 152 eligible patients, 85 (55.9%) received carbapenems and 67 (44.1%) received non-carbapenems. Non-carbapenem antibiotics used in this cohort included aminoglycosides (n = 30), β-lactam/β-lactamase inhibitors (n = 13), fluoroquinolones (n = 12) and trimethoprim/sulfamethoxazole (n = 5). Microbiological failure was observed in 16 patients receiving carbapenems (16/83, 19.3%) versus 4 patients receiving non-carbapenem (4/67, 6.0%). After weighting, the risk of microbiological failure was similar between the two groups [weighted hazard ratio (HR) 0.99; 95% CI 0.31-3.19]. In a multivariable regression analysis combined with weights, the estimate did not change (weighted adjusted HR 0.96; 95% CI 0.41-2.27). The clinical failure rate was also similar in the two groups (weighted HR 1.05; 95% CI 0.24-4.62).
These results suggest that non-carbapenem antibiotics were as effective as carbapenems as definitive therapy for treating community-onset APN caused by ESBL-producing E. coli if they are active in vitro.
[Show abstract][Hide abstract] ABSTRACT: Objectives:
Some patients with suspected ST-segment elevation (STE) myocardial infarction (STEMI) show STE that does not fulfill the current criteria for STEMI. The purpose of this study was to investigate the characteristics and prognoses of patients with minimal STEMI.
Between November 2007 and December 2011, 546 patients who underwent primary percutaneous coronary intervention (PCI) for STEMI were enrolled.
The minimal STE group had a higher proportion of women (30.2 vs. 21.0%, p = 0.031), better pre-PCI antegrade flow (Thrombolysis in Myocardial Infarction flow 2-3, 30.2 vs. 18.8%, p = 0.006) and better collateralization (Rentrop score 2-3, 27.4 vs. 18.1%, p = 0.024) compared to the definite STE group. Multivariate analysis showed that each of them were independent predictors for minimal STE. However, 1-year mortality of the minimal STE group did not differ from that of the definite STE group (7.1 vs. 9.3%, log-rank p = 0.315).
Female gender, good collateral flow and good pre-PCI antegrade flow were independent predictors for minimal STE in patients with STEMI. However, minimal STE was not related to a good prognosis in patients with STEMI.
[Show abstract][Hide abstract] ABSTRACT: For hypersonic aircraft, increase of flight speeds causes heat loads that are from aerodynamic heat and engine heat. The heat loads could lead structural change of aircraft's component and malfunctioning. Endothermic fuels are liquid hydrocarbon fuels which are able to absorb the heat loads by undergoing endothermic reactions, such as thermal and catalytic cracking. In this study, methylcyclohexane was selected as a model endothermic fuel and experiments on endothermic properties were implemented. To improve heat of endothermic reaction, we applied zeolites and confirmed that HZSM-5 was the best catalyst for the catalytic performance. The objective is to investigate catalytic effects for heat sink improvement. The catalyst could be applied to system that use kerosene fuel as endothermic fuel.