Betulinic acid (BA) is a naturally arising pentacyclic triterpenoid that has anti-malarial, anti-retroviral, anti-inflammatory, and anti-cancer biological effects. More recently, it has been reported ...to possess anti-obesity activity mediated by the activation of AMP-activated protein kinase (AMPK). We further investigated antidiabetic activity of BA in mouse tissues at the cellular and systemic levels. We found that BA stimulated AMPK in a similar fashion to the known AMPK activators, such as 5-aminoimidazole-4-carboxamide-1-β-D-ribofuranoside and metformin. Notably, the level of glucose uptake by BA was not altered by wortmannin, suggesting that this activation did not depend on phosphoinositide 3-kinase. Furthermore, BA diminished blood glucose levels in alloxane-treated ICR mice and in untreated mice during the glucose tolerance test. BA also stimulated mRNA expression of glucose transporter 4, which could partly explain increased glucose uptake. BA also increased AS160 phosphorylation by insulin-independent mechanisms in the extensor digitorum longus muscle. These results indicate that BA may serve as a promising therapeutic agent for diabetes by activating AMPK, like metformin. Notably, BA also enhanced mouse endurance capacity, indicating that it also affects metabolic regulation in addition to its antidiabetic activity.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The goal of the study was to determine whether endoscopic ultrasound (EUS)-guided biliary drainage (EUS-BD) is comparable to conventional transpapillary stenting with endoscopic retrograde ...cholangiopancreatography (ERCP) in palliation of malignant distal biliary obstruction. Although ERCP for the palliation of malignant biliary obstruction is the standard of care, post-procedure pancreatitis and stent dysfunctions are not uncommon. While EUS-BD has garnered interest as a viable alternative when ERCP is impossible, its role as a primary palliation of malignant distal biliary obstruction is yet to be proven.
We performed random allocation to EUS-BD or ERCP in 125 patients with unresectable malignant distal biliary obstruction at four tertiary academic referral centers in South Korea.
Technical success rates were 93.8% (60/64) for EUS-BD and 90.2% (55/61) for ERCP (difference 3.6%, 95% 1-sided confidence interval lower limit -4.4%, P = 0.003 for noninferiority margin of 10%). Clinical success rates were 90.0% (54/60) in EUS-BD and 94.5% (52/55) in ERCP (P = 0.49). Lower rates of overall adverse events (6.3% vs 19.7%, P = 0.03) including post-procedure pancreatitis (0 vs 14.8%), reintervention (15.6% vs 42.6%), and higher rate of stent patency (85.1% vs 48.9%) were observed with EUS-BD. EUS-BD was also associated with more preserved quality of life (QOL) than transpapillary stenting after 12 weeks of the procedure.
This study demonstrated comparable technical and clinical success rates between EUS-BD and ERCP in relief malignant distal biliary obstruction. Substantially longer duration of patency coupled with lower rates of adverse events and reintervention, and more preserved QOL were observed with EUS-BD (cris.nih.go.kr, Identifier: KCT0001396, https://cris.nih.go.kr/cris/search/search_result_st01_en.jsp?seq=9716<ype=&rtype= ).
An Si photoelectrode with a nanoporous Au thin film for highly selective and efficient photoelectrochemical (PEC) CO2 reduction reaction (CO2RR) is presented. The nanoporous Au thin film is formed by ...electrochemical reduction of an anodized Au thin film. The electrochemical treatments of the Au thin film critically improve CO2 reduction catalytic activity of Au catalysts and exhibit CO Faradaic efficiency of 96% at 480 mV of overpotential. To apply the electrochemical pretreatment of Au films for PEC CO2RR, a new Si photoelectrode design with mesh‐type co‐catalysts independently wired at the front and the back of the photoelectrode is demonstrated. Due to the superior CO2RR activity of the nanoporous Au mesh and high photovoltage from Si, the Si photoelectrode with the nanoporous Au thin film mesh shows conversion of CO2 to CO with 91% Faradaic efficiency at positive potential than the CO2/CO equilibrium potential.
Si photoelectrode with a nanoporous Au thin film is proposed for highly selective and efficient photoelectrochemical (PEC) CO2 reduction reaction (CO2RR). The nanoporous Au thin film by electrochemical pretreatments exhibits critically improved CO2 reduction activity. For PEC CO2RR, an Si photoelectrode combined with mesh‐type nanoporous Au co‐catalysts achieves 91% CO2 conversion selectivity at positive potential than the CO2/CO equilibrium potential.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Ischaemic heart disease (IHD) is the leading cause of death worldwide. Although myocardial cell death plays a significant role in myocardial infarction (MI), its underlying mechanism remains to be ...elucidated. To understand the progression of MI and identify potential therapeutic targets, we performed tandem mass tag (TMT)-based quantitative proteomic analysis using an MI mouse model. Gene ontology (GO) analysis and gene set enrichment analysis (GSEA) revealed that the glutathione metabolic pathway and reactive oxygen species (ROS) pathway were significantly downregulated during MI. In particular, glutathione peroxidase 4 (GPX4), which protects cells from ferroptosis (an iron-dependent programme of regulated necrosis), was downregulated in the early and middle stages of MI. RNA-seq and qRT-PCR analyses suggested that GPX4 downregulation occurred at the transcriptional level. Depletion or inhibition of GPX4 using specific siRNA or the chemical inhibitor RSL3, respectively, resulted in the accumulation of lipid peroxide, leading to cell death by ferroptosis in H9c2 cardiomyoblasts. Although neonatal rat ventricular myocytes (NRVMs) were less sensitive to GPX4 inhibition than H9c2 cells, NRVMs rapidly underwent ferroptosis in response to GPX4 inhibition under cysteine deprivation. Our study suggests that downregulation of GPX4 during MI contributes to ferroptotic cell death in cardiomyocytes upon metabolic stress such as cysteine deprivation.
Electrochemical CO2 conversion offers a promising route for value-added products such as formate, carbon monoxide, and hydrocarbons. As a result of the highly required overpotential for CO2 ...reduction, researchers have extensively studied the development of catalyst materials in a typical H-type cell, utilizing a dissolved CO2 reactant in the liquid phase. However, the low CO2 solubility in an aqueous solution has critically limited productivity, thereby hindering its practical application. In efforts to realize commercially available CO2 conversion, gas-phase reactor systems have recently attracted considerable attention. Although the achieved performance to date reflects a high feasibility, further development is still required in order for a well-established technology. Accordingly, this review aims to promote the further study of gas-phase systems for CO2 reduction, by generally examining some previous approaches from liquid-phase to gas-phase systems. Finally, we outline major challenges, with significant lessons for practical CO2 conversion systems.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Although percutaneous transhepatic biliary drainage (PTBD) is the standard method for draining a malignant biliary obstruction after failed endoscopic retrograde cholangiopancreatographies (ERCPs), ...use of endoscopic ultrasound-guided transmural biliary drainage (EUS-BD) is increasing. We performed a multicenter, open-label, randomized trial to compare EUS-BD vs PTBD for malignant distal biliary obstruction after a failed ERCP.
Patients with unresectable malignant distal biliary obstructions and failed primary ERCP, caused by inaccessible papilla, were assigned to groups that underwent EUS-BD with an all-in-one device for direct deployment of a partially covered metal stent (without further fistula tract dilation, n = 34) or PTBD (n = 32). The procedures were performed at 4 tertiary academic referral centers in South Korea from October 2014 through March 2015; patients were followed up through June 2015. The primary end point was technical success, which was calculated using a noninferiority model. Secondary end points were functional success, procedure-related adverse events, rate of unscheduled re-intervention, and quality of life (QOL).
The rates of primary technical success were 94.1% (32 of 34) in the EUS-BD group and 96.9% (31 of 32) in the PTBD group (1-sided 97.5% confidence interval lower limit, -12.7%; P = .008 for a noninferiority margin of 15%). The rates of functional success were 87.5% (28 of 32) in the EUS-BD group and 87.1% (27 of 31) in the PTBD group (P = 1.00). The proportions of procedure-related adverse events were 8.8% in the EUS-BD group vs 31.2% in the PTBD group (P = .022); the mean frequency of unscheduled re-intervention was 0.34 in the EUS-BD group vs 0.93 in the PTBD group (P = .02). The QOL was similar between groups.
EUS-BD and PTBD had similar levels of efficacy in patients with unresectable malignant distal biliary obstruction and inaccessible papilla based on rates of technical and functional success and QOL. However, EUS-BD produced fewer procedure-related adverse events and unscheduled re-interventions. Clinical trial registration no: cris.nih.go.kr/KCT0001370.
As the western North Pacific Ocean is located downwind of the source regions for spring Asian dust, it is an ideal location for determining the response of open waters to these events. Spatial ...analysis of spring Asian dust events from source regions to the western North Pacific, using long‐term daily aerosol index data, revealed three different transport pathways supported by the westerly wind system: one passing across the northern East/Japan Sea (40°N–50°N), a second moving over the entire East/Japan Sea (35°N–55°N), and a third flowing predominantly over the Siberian continent (>50°N). Our results indicate that strong spring Asian dust events can increase ocean primary productivity by more than 70% (>2‐fold increase in chlorophyll‐a concentrations) compared to weak/nondust conditions. Therefore, attention should be paid to the recent downturn in the number of spring Asian dust events and to the response of primary production in the western North Pacific to this change.
Key Points
There were three different transport pathways for spring Asian dust events in the study area
Ocean primary productivity was significantly increased by the spring Asian dust events
There has been a recent decrease in spring Asian dust events in the western North Pacific Ocean
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Electrochemical CO2 reduction is one of the promising ways to convert CO2 to value-added products such as CO. Many studies have dealt with suppressing the hydrogen evolution reaction (HER) and ...increasing the CO2 reduction reaction (CO2RR) through modification of the metal surface with additives such as anchoring agent, anion, etc. However, there are only a few studies about modifying the Au surface with additives. We present here a theoretical prediction that the addition of the CN and Cl species on an Au electrode would enhance the electrochemical CO2RR due to van der Waals interactions with these large anionic species. On the basis of this suggestion, we then prepared functionalized Au electrodes by electroplating in an aqueous solution containing CN– or Cl– and experimentally verified that the CO2RR of functionalized Au indeed shows exceptional CO2RR activity in comparison to pristine Au.
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IJS, KILJ, NUK, PNG, UL, UM
A NiO-Y
2
O
3
stabilized ZrO
2
(NiO-YSZ) supported tubular solid oxide cell, which consists of a La
0.9
Sr
0.1
Ga
0.8
Mg
0.2
O
3−
δ
(LSGM) dip-coated electrolyte film and Sm
0.5
Sr
0.5
CoO
3−
δ
(SSC) ...air electrode, was prepared and its power generation and electrolysis performance in the intermediate temperature range were investigated. Compared to other rare earth oxides studied, infiltration of Ce nitrate into the substrate was the most effective for increasing cell performance in the case of 2 M infiltration. Moreover, it was found that the infiltration of a higher concentration of the Ce solution increased the maximum power density, because both IR loss and overpotential were significantly decreased. The maximum power density of the cell was 0.95 and 0.42 W cm
−2
at 873 and 773 K, respectively at 3 M Ce nitrate infiltration. The long-term stability of the cell was also measured by using the cell infiltrated with 1.5 M Ce, and a stable power generation performance was demonstrated up to 100 h. The steam electrolysis performance of the cell using Ce infiltration was further studied and it was found that Ce also contributes to higher current density in SOEC operation and 1.07 A cm
−2
at 1.6 V was achieved at 873 K using 2 M Ce infiltration.
Ce infiltration into a NiO-YSZ tubular substrate is significantly effective for increasing the SORC performance using a LSGM electrolyte.
Background and Aims Radiofrequency ablation (RFA) has been used as a valuable treatment modality for various unresectable malignancies. EUS-guided radiofrequency ablation (EUS-RFA) of the porcine ...pancreas was reported to be feasible and safe in our previous study, suggesting that EUS-RFA may be applicable as an adjunct and effective alternative treatment method for unresectable pancreatic cancer. This study aimed to assess the technical feasibility and safety of EUS-RFA for unresectable pancreatic cancer. Methods An 18-gauge endoscopic RFA electrode and a radiofrequency generator were used for the procedure. The length of the exposed tip of the RFA electrode was 10 mm. After insertion of the RFA electrode into the mass, the radiofrequency generator was activated to deliver 20 to 50 W ablation power for 10 seconds. Depending on tumor size, the procedure was repeated to sufficiently cover the tumor. Results EUS-RFA was performed successfully in all 6 patients (median age 62 years, range 43-73 years). Pancreatic cancer was located in the head (n = 4) or body (n = 2) of the pancreas. The median diameter of masses was 3.8 cm (range 3cm-9cm). Four patients had stage 3 disease, and 2 patients had stage 4 disease. After the procedure, 2 patients experienced mild abdominal pain, but there were no other adverse events such as pancreatitis or bleeding. Conclusions EUS-RFA could be a technically feasible and safe option for patients with unresectable pancreatic cancer.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
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