Carbon-based catalysts have attracted much attention for the dehydrogenation (DH) of organic molecules, due to their rich active sites, high conversion efficiency, and selectivity. However, because ...of their poor stability at high operation temperature and relatively high cost, their practical applications have been limited. Here, we report a simple ball-milling-induced mechanochemical reaction which can introduce iron (Fe) and different functional groups (mostly stable aromatic CO after heat-treatment) along the edges of graphitic nanoplatelets. The resulting Fe-graphitic nanoplatelets (Fe-XGnPs, X = H, C, N, or V) provide active sites for the oxidative dehydrogenation (ODH) of ethylbenzene into styrene. Among them, Fe-NGnPs (X = N) displayed the highest performance for styrene production at low temperature (∼11.13 mmol g–1 h–1, 450 °C) with high selectivity and durability.
Full text
Available for:
IJS, KILJ, NUK, PNG, UL, UM
Graphitic nanoplatelets (GnPs), edge-selectively carboxylated graphitic nanoplatelets (ECGnPs), are functionalized with a carboxylic acid at the edge increasing their surface area, and are highly ...dispersible in various solvents. However, there is a limit in that the basal plane remains intact because it is functionalized only in the part where the radical is generated at the edge. Here, we activate ECGnPs to have porous structures by flowing CO2 at 900 °C. Etching of the ECGnPs structure was performed through the Boudouard reaction, and the surface area increased from 579 m2 g-1 to a maximum of 2462 m2 g-1. In addition, the pore structure was investigated with various adsorption gases (CH4, Ar, CO2, H2, and N2) according to the reaction time. This study provides the overall green chemistry in that it utilizes CO2 from manufacturing to activation compared to the process of activating with conventional chemical treatment.
Full text
Available for:
BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Solid-state reaction of organic molecules holds a considerable advantage over liquid-phase processes in the manufacturing industry. However, the research progress in exploring this benefit is largely ...staggering, which leaves few liquid-phase systems to work with. Here, we show a synthetic protocol for the formation of a three-dimensional porous organic network via solid-state explosion of organic single crystals. The explosive reaction is realized by the Bergman reaction (cycloaromatization) of three enediyne groups on 2,3,6,7,14,15-hexaethynyl-9,10-dihydro-9,10-1,2benzenoanthracene. The origin of the explosion is systematically studied using single-crystal X-ray diffraction and differential scanning calorimetry, along with high-speed camera and density functional theory calculations. The results suggest that the solid-state explosion is triggered by an abrupt change in lattice energy induced by release of primer molecules in the 2,3,6,7,14,15-hexaethynyl-9,10-dihydro-9,10-1,2benzenoanthracene crystal lattice.
The time at which hypertension treatment should be initiated for different age groups and sexes remains controversial. We aimed to determine whether the association between blood pressure (BP) and ...major adverse cardiovascular events (MACE) varies with age and sex. This study enrolled 327,328 subjects who had not taken antihypertensive medication in the Korean National Health Service-National Health Screening Cohort between 2002 and 2003. Participants were categorized into four groups according to 2017 American College of Cardiology/American Heart Association hypertension guideline. Primary outcome was MACE characterized by cardiovascular mortality, myocardial infarction, unstable angina, and stroke. During a 10-year follow-up, a significant increase in MACE risk was observed from the stage 1 hypertension group (hazard ratio HR, 1.23; 95% CI 1.15-1.32; P < 0.001) in time-varying Cox analysis. This relationship was persistent in subjects aged < 70 years, but increased MACE risk was observed only in the stage 2 hypertension group in ≥ 70 years (HR, 1.52; 95% CI 1.32-1.76, P < 0.001). When categorized as per sex, both men and women showed significant MACE risk from stage 1 hypertension. However, on comparing the sexes after stratifying by age, a significantly increased risk of MACE was shown from stage 1 hypertension in men aged < 50 years, but from stage 2 hypertension in men aged ≥ 50 years. Meanwhile, increased MACE risk was observed from stage 2 hypertension in women aged < 60 years, but from stage 1 hypertension in women aged ≥ 60 years. Thus, young male subjects had higher MACE risk than young female subjects, but this difference gradually decreased with age and there was no difference between sexes in subjects aged ≥ 70 years. Therefore, our results suggest that hypertension treatment initiation may need to be individualized depending on age and sex.
Full text
Available for:
IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
This study aimed to investigate the patterns of preferred endoscopic procedure types and techniques for managing difficult common bile duct (CBD) stones in South Korea.
The Committee of Policy and ...Quality Management of Korean Pancreatobiliary Association (KPBA) conducted a survey containing 19 questions. Both paper and online surveys were carried out; with the paper survey being conducted during the 2019 Annual Congress of KPBA and the online survey being conducted through Google Forms from April 2020 to February 2021.
The response rate was approximately 41.3% (86/208). Sixty-two (73.0%) worked at tertiary hospitals or academic medical centers, and 60 (69.7%) had more than 5 years of endoscopic retrograde cholangiopancreatography experience. The preferred size criteria for large CBD stones were 15 mm (40.6%), 20 mm (31.3%), and 30 mm (4.6%). For managing of large CBD stones, endoscopic papillary large balloon dilation after endoscopic sphincterotomy was the most preferred technique (74.4%). When performing procedures in those with bleeding diathesis, 64 (74.4%) respondents favored endoscopic papillary balloon dilation (EPBD) alone or EPBD with small endoscopic sphincterotomy. Fifty-five respondents (63.9%) preferred the doubleguidewire technique when faced with difficult bile duct cannulation in patients with periampullary diverticulum. In surgically altered anatomies, cap-fitted forward viewing endoscopy (76.7%) and percutaneous transhepatic cholangioscopy (48.8%) were the preferred techniques for Billroth-II anastomosis and total gastrectomy with Roux-en-Y anastomosis, respectively.
Most respondents showed unifying trends for the management of difficult CBD stones. The current practice patterns could be used as basic data for clinical quality improvements in the management of difficult CBD stones.
Chronic fatigue syndrome (CFS) is one of the most intractable diseases and is characterized by severe central fatigue that impairs even daily activity. To date, the pathophysiological mechanisms are ...uncertain and no therapies exist. Therefore, a proper animal model reflecting the clinical features of CFS is urgently required. We compared two CFS animal models most commonly used, by injection with lipopolysaccharide (LPS from
O111:B4) or polyinosinic: polycytidylic acid (poly I:C), along with bilateral adrenalectomy (ADX) as another possible model. Both LPS- and poly I:C-injected mice dominantly showed depressive behaviors, while ADX led to fatigue-like performances with high pain sensitivity. In brain tissues, LPS injection notably activated microglia and the 5-hydroxytryptamine (HT)
receptor in the prefrontal cortex and hippocampus. Poly I:C-injection also remarkably activated the 5-HT transporter and 5-HT
receptor with a reduction in serotonin levels in the brain. ADX particularly activated astrocytes and transforming growth factor beta (TGF-β) 1 in all brain regions. Our results revealed that LPS and poly I:C animal models approximate depressive disorder more closely than CFS. We suggest that ADX is a possible method for establishing a mouse model of CFS reflecting clinical features, especially in neuroendocrine system.
Full text
Available for:
IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
•Carbapenem-resistant Enterobacterales (CRE) strains (n=3675) were collected in Seoul, Republic of Korea.•mcr genes (mcr-1, -4, -9 and -10) were detected in 2.2% (80/3675) of CRE ...strains.•Enterobacter cloacae complex strains (20.5%) were positive for mcr-9 or mcr-10.•mcr genes have been silently disseminating among CRE strains in Seoul.
Colistin is often used as a drug of last resort against infections caused by multi-drug-resistant Gram-negative bacteria, including carbapenem-resistant Enterobacterales (CRE). Recently, the acquisition of mobile colistin resistance (mcr) genes by CRE has become a cause for concern. This study investigated the prevalence of mcr genes in CRE isolates in Seoul, Republic of Korea. In total, 3675 CRE strains were collected from patients between 2018 and 2019, and initially screened for mcr genes using multiplex polymerase chain reaction assays. Upon the identification of mcr-harbouring strains, colistin susceptibility tests, identification of carbapenemase and β-lactamase genes, and plasmid replicon typing were performed. Clonal analysis was conducted using pulsed-field gel electrophoresis. mcr genes were detected in 2.2% (80/3675) of CRE strains. There were three mcr-1 carriers, one mcr-4.3 carrier, one mcr-4.3/mcr-9 carrier, 58 mcr-9 carriers, one mcr-9/mcr-10 carrier and 16 mcr-10 carriers among various Enterobacterales species, of which 60 were Enterobacter cloacae complex (ECC) strains. The prevalence of mcr genes in ECC strains was 20.5%. Molecular detection confirmed that 21.3% and 13.8% of mcr-harbouring strains shared blaNDM-1 or blaKPC-2, respectively. In addition, an IncHI2 replicon was identified in 71.7% of mcr-9 strains. Comparative analysis revealed not only a notable diversity of mcr carriers, but also clonal spreading or nosocomial outbreaks of some ECC strains. These findings revealed a silent distribution of mcr genes in CRE strains with high genetic heterogeneity in Seoul, underscoring the urgent need for timely intervention to control and prevent mcr dissemination.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
A 12-lead ECG is a simple and less costly measure to assess cardiac amyloidosis and may reflect the infiltrative nature of cardiac amyloidosis and have prognostic value for predicting overall ...survival in patients with cardiac AL amyloidosis. Therefore, we investigated the associations of surface ECG parameters with left ventricular (LV) global longitudinal strain (GLS) and prognosis in patients with cardiac AL amyloidosis. We performed a multi-center, retrospective analysis of 102 biopsy-proven cardiac AL amyloidosis patients. Baseline studies included 12-lead surface ECG and echocardiography, with two-dimensional strain analysis performed within one month of diagnosis. From the Kaplan-Meier survival analysis, patients with prolonged QTc (≥483 msec) had significantly poorer survival. ECG scores were assigned according to presence of prolonged QTc (≥483 msec) and abnormal QRS axis, and the study participants were divided into three groups according to ECG score. Mean absolute value of LV GLS and regional LV longitudinal strain (LS) differed significantly among the three groups and decreased in a stepwise manner as ECG score increased. Log NT-proBNP increased in a stepwise manner as ECG score increased. Prolonged QTc (≥483 msec) and abnormal QRS axis showed significant incremental values in addition to the revised Mayo stage. The presence of prolonged QTc (≥483 msec) and abnormal QRS axis showed significant incremental values for overall mortality rates. In addition, ECG scores consisting of presence of prolonged QTc (≥483 msec), and abnormal QRS axis showed good association with longitudinal LV dysfunction and NT-proBNP. ECG finding may provide prognostic additional information regarding prognosis of AL amyloidosis with cardiac involvement.
Full text
Available for:
IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Endoscopic retrograde cholangiopancreatography (ERCP) is a procedure that requires significant experiences and skills and has various procedure-related complications, some of which can be severe and ...even result in the death of patients. Expanding ERCP availability has the advantage of increasing accessibility for patients. However, ERCP poses a substantial risk if performed without proper quality management. ERCP quality management is essential for both ensuring safe and successful procedures and meeting the social demands for enhanced healthcare competitiveness and quality assurance. To address these concerns, the Korean Pancreatobiliary Association established a task force to develop ERCP quality indicators (QIs) tailored to the Korean medical environment. Key questions for five pre-procedure, three intra-procedure, and four post-procedure measures were formulated based on a literature search related to ERCP QIs and a comprehensive clinical review conducted by experts. The statements and recommendations regarding each QI item were selected through peer review. The developed ERCP QIs were reviewed by external experts based on the latest available evidence at the time of development. These domestically tailored ERCP QIs are expected to contribute considerably to improving ERCP quality in Korea.
Although endoscopic ultrasound (EUS)-guided fine needle aspiration (FNA) and fine needle biopsy (FNB) are widely used for tissue acquisition of pancreatic solid mass, the optimal strategy of this ...procedure has not been established yet. The aim of this nationwide study was to investigate the current practice patterns of EUS-FNA/FNB for pancreatic solid mass in Korea.
The Policy-Quality Management of the Korean Pancreatobiliary Association (KPBA) developed a questionnaire containing 22 questions. An electronic survey consisting of the questionnaire was distributed by e-mail to members registered to the KPBA.
A total of 101 respondents completed the survey. Eighty respondents (79.2%) performed preoperative EUS-FNA/FNB for operable pancreatic solid mass. Acquire needles (60.4%) were used the most, followed by ProCore needles (47.5%). In terms of need size, most respondents (>80%) preferred 22-gauge needles regardless of the location of the mass. Negative suction with a 10-mL syringe (71.3%) as sampling technique was followed by stylet slow-pull (41.6%). More than three needle passes for EUS-FNA/FNB was performed by most respondents (>80%). The frequency of requiring repeated procedure was significantly higher in respondents with a low individual volume (<5 per month, p=0.001). Prophylactic antibiotics were routinely used in 39 respondents (38.6%); rapid on-site pathologic evaluation was used in 6.1%.
According to this survey, practices of EUS-FNA/FNB for pancreatic solid mass varied substantially, some of which differed considerably from the recommendations present in existing guidelines. These results suggest that the development of evidence-based quality guidelines fitting Korean clinical practice is needed to establish the optimal strategy for this procedure.
PDF
