Multidimensional hierarchical architecturing is a promising chemical approach to provide unique characteristics synergistically integrated from individual nanostructured materials for energy storage ...applications. Herein, hierarchical complex hybrid architectures of CNT‐on‐OCNT‐Fe are reported, where iron oxide nanoparticles are encapsulated inside carbon nanotube (CNT) branches grown onto the ozone‐treated surface of 3D CNT internetworked porous structures. The activated surface of the 3D ozonated CNT (OCNT) interacts with the iron oxide nanoparticles, resulting in different chemical environments of inner and outer tubes and large surface area. The mixed phases of iron oxide nanoparticles are confined by full encapsulation inside the conductive nanotubes and act as catalysts to vertically grow the CNT branches. This unique hierarchical architecture allows CNT‐on‐OCNT‐Fe to achieve a reasonable capacity of >798 mA h g−1 at 50 mA g−1, with outstanding rate capability (≈72% capacity retention at rates from 50 to 1000 mA g−1) and cyclic stability (>98.3% capacity retention up to 200 cycles at 100 mA g−1 with a coulombic efficiency of >97%). The improved rate and cyclic capabilities are attributed to the hierarchical porosity of 3D OCNT internetworks, the shielding of CNT walls for encapsulated iron oxide nanoparticles, and a proximate electronic pathway for the isolated nanoparticles.
Hierarchical complex hybrid architectures of carbon nanotube (CNT)‐on‐ozonated carbon nanotube (OCNT)‐Fe are constructed encapsulating iron oxide nanoparticles inside CNT branches grown onto the ozone‐treated surface of 3D CNT internetworked porous structures for greatly improved rate and cyclic capabilities of lithium‐ion batteries.
We screened a chemical library in MCF-7 cells stably expressing green fluorescent protein (GFP)-conjugated microtubule-associated protein 1 light chain 3 (LC3) (GFP-LC3-MCF-7) using cell-based assay, ...and identified BIX-01294 (BIX), a selective inhibitor of euchromatic histone-lysine N-methyltransferase 2 (EHMT2), as a strong autophagy inducer. BIX enhanced formation of GFP-LC3 puncta, LC3-II, and free GFP, signifying autophagic activation. Inhibition of these phenomena with chloroquine and increasement in punctate dKeima ratio (550/438) signal indicated that BIX activated autophagic flux. BIX-induced cell death was suppressed by the autophagy inhibitor, 3-methyladenine, or siRNA against BECN1 (VPS30/ATG6), ATG5, and ATG7, but not by caspase inhibitors. Moreover, EHMT2 siRNA augmented GFP-LC3 puncta, LC3-II, free GFP, and cell death, implying that inhibition of EHMT2 caused autophagy-mediated cell death. Treatment with EHMT2 siRNA and BIX accumulated intracellular reactive oxygen species (ROS). BIX augmented mitochondrial superoxide via NADPH oxidase activation. In addition, BIX increased hydrogen peroxide and glutathione redox potential in both cytosol and mitochondria. Treatment with N-acetyl-L-cysteine (NAC) or diphenyleneiodonium chloride (DPI) decreased BIX-induced LC3-II, GFP-LC3 puncta, and cell death, indicating that ROS instigated autophagy-dependent cell death triggered by BIX. We observed that BIX potentiated autophagy-dependent and caspase-independent cell death in estrogen receptor (ESR)-negative SKBr3 and ESR-positive MCF-7 breast cancer cells, HCT116 colon cancer cells, and importantly, in primary human breast and colon cancer cells. Together, the results suggest that BIX induces autophagy-dependent cell death via EHMT2 dysfunction and intracellular ROS accumulation in breast and colon cancer cells, therefore EHMT2 inhibition can be an effective therapeutic strategy for cancer treatment.
Background
Glutamate chemical exchange saturation transfer (GluCEST) imaging has been widely used in brain psychiatric disorders. Glutamate signal changes may help to evaluate the sleep‐related ...disorders, and could be useful in diagnosis.
Purpose
To evaluate signal changes in the hippocampus and cortex of a rat model of stress‐induced sleep disturbance using GluCEST.
Study Type
Prospective animal study.
Animal Model
Fourteen male Sprague–Dawley rats.
Field Strength/Sequence
7.0T small bore MRI / fat‐suppressed, turbo‐rapid acquisition with relaxation enhancement (RARE) for CEST, and spin‐echo, point‐resolved proton MR spectroscopy (1H MRS).
Assessment
Rats were divided into two groups: the stress‐induced sleep‐disturbance group (SSD, n = 7) and the control group (CTRL, n = 7), to evaluate and compare the cerebral glutamate signal changes. GluCEST data were quantified using a conventional magnetization transfer ratio asymmetry in the left‐ and right‐side hippocampus and cortex. The correlation between GluCEST signal and glutamate concentrations, derived from 1H MRS, was evaluated.
Statistical Analysis
Wilcoxon rank‐sum test between CEST signals and multiparametric MR signals, Wilcoxon signed‐rank test between CEST signals on the left and right hemispheres, and a correlation test between CEST signals and glutamate concentrations derived from 1H MRS.
Results
Measured GluCEST signals showed significant differences between the two groups (left hippocampus; 4.23 ± 0.27% / 5.27 ± 0.42% SSD / CTRL, P = 0.002, right hippocampus; 4.50 ± 0.44% / 5.04 ± 0.34% P = 0.035, left cortex; 2.81 ± 0.38% / 3.56 ± 0.41% P = 0.004, and right cortex; 2.95 ± 0.47% / 3.82 ± 0.26% P = 0.003). GluCEST signals showed positive correlation with glutamate concentrations (R2 = 0.312; P = 0.038).
Data Conclusion
GluCEST allowed the visualization of cerebral glutamate changes in rats subjected to sleep disturbance, and may yield valuable insights for interpreting alterations in cerebral biochemical information.
Level of Evidence: 2
Technical Efficacy: Stage 2
J. Magn. Reson. Imaging 2019;50:1866–1872.
Abstract
This study aimed to investigate the association between domain-specific physical activity (PA) and diabetes in Korean adults. We analyzed 26,653 men and women (aged > 18 years) from the ...Korea National Health and Nutrition Examination Survey (2014–2018). PA was measured using a validated Global PA Questionnaire. Multivariable logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) after adjustment for various confounders. Transport PA accounted for the majority of total PA (46%, men; 58%, women), followed by leisure-time PA (30%; 22%) and work PA (24%; 20%). In men, ORs (95% CI) of diabetes comparing ≥ 600 metabolic task of equivalent (MET)-min/week vs. no activity were 0.82 (0.71–0.95) for leisure-time PA, 0.85 (0.75–0.96) for transport PA, and 0.88 (0.78–0.99) for leisure-time + transport PA. In women, ORs (95% CI) of diabetes comparing the same groups were 0.73 (0.60–0.89) for leisure-time PA, 0.97 (0.85–1.10) for transport PA, and 0.88 (0.78–1.00) for leisure-time + transport PA. However, work PA showed no association with diabetes. In conclusion, leisure-time PA was inversely associated with diabetes in both men and women, while transport PA was inversely associated only in men. But work PA was not associated with diabetes in Korean adults.
Little is known of nosocomial infections (NI) in patients who suffer from in-hospital cardiac arrest who undergoing extracorporeal cardiopulmonary resuscitation. This study aimed to investigate ...clinical pictures of NI, and the association of NIs with clinical outcomes in in-hospital cardiac arrest patients who undergoing extracorporeal cardiopulmonary resuscitation.
To evaluate the incidence and clinical characteristics of NI in patients who undergoing extracorporeal cardiopulmonary resuscitation, a retrospective cohort study was conducted in a single tertiary referral center between January 2010 and December 2018. We included adult patients who undergoing extracorporeal cardiopulmonary resuscitation for in-hospital cardiac arrest and excluded patients who were out-of-hospital cardiac arrest or failed ECMO implantation. Clinical characteristics and outcomes were compared between NI and Non-NI patients, or multidrug-resistant (MDR) and non-MDR. The independent risk factors associated with NIs were also analyzed using multivariable logistic regression model.
Thirty-five (23.3%) patients developed a NI. These cases included 21 patients with a gram negative (G-) infection, 12 patients with a gram positive (G+) bacterial infection, and two patients with fungal infection. Pneumonia was the most common type of NIs, followed by catheter-related infection. The in-hospital mortality and neurologic outcomes at discharge were not different between the NI and non-NI groups. Multidrug-resistant (MDR) pathogens were detected in 10 cases (28.6%). The MDR NI patients had a higher ICU mortality than did those with non-MDR NI (80% vs. 32%, p = 0.028). Following multivariable adjustment, body mass index (adjusted OR 0.87, 95% CI, 0.77-0.97, p = 0.016) and cardiopulmonary resuscitation to pump on time (adjusted OR 1.04, 95% CI, 1.01-1.06, p = 0.001) were independent predictors of NI development.
In patients who received extracorporeal cardiopulmonary resuscitation, NIs were not associated with an increase in in-hospital mortality. However, NIs with MDR organisms do increase the risk of in-hospital mortality. Lower body mass index and longer low flow time were significant predictors of NI development.
Vitamin D deficiency is a worldwide health issue especially in women. Serum vitamin D concentrations vary depending on the weather. However, the ideal vitamin D supplementation strategy related to ...weather remains uncertain. We aimed to investigate the relationship between climate factors and serum 25-hydroxy vitamin D 25(OH)D concentrations. This study included 11,272 women aged 20-79 who visited a health promotion center for annual checkups between January 2013 and December 2015. We reviewed medical records and collected daily meteorological data. We analyzed the association between serum 25(OH)D concentration and climate factors using simple and multiple regression models and then predicted serum 25(OH)D concentration using multiple fractional polynomial models. The median age of the participants was 51 years (20-79 years), and the mean serum 25(OH)D level was 17.4 ± 8.6 ng/mL. The serum 25(OH)D concentration was lower in young women than in older women. The proportions of women with adequate 25(OH)D levels were 14.9% and 47.0% in the age groups 20-29 and 70-79, respectively. The maximum level of predicted log 25(OH)D was found in September, and the minimum was found in January. In multiple regression analysis, age and monthly mean temperature were associated with 25(OH)D concentrations. Serum 25(OH)D level was predicted using the following formula: log (25(OH)D) = 2.144 + 0.009 × age + 0.018 × ((temperature + 12.4)/10)2 (P < 0.001, adjusted R2 = 0.091). Serum 25(OH)D concentrations changed according to air temperature. An adequate strategy for vitamin D supplementation, based on air temperature, is necessary to maintain healthy serum 25(OH)D levels.
Abstract
Precise doping-profile engineering in van der Waals heterostructures is a key element to promote optimal device performance in various electrical and optical applications with ...two-dimensional layered materials. Here, we report tungsten diselenide- (WSe
2
) based pure vertical diodes with atomically defined p-, i- and n-channel regions. Externally modulated p- and n-doped layers are respectively formed on the bottom and the top facets of WSe
2
single crystals by direct evaporations of high and low work-function metals platinum and gadolinium, thus forming atomically sharp p–i–n heterojunctions in the homogeneous WSe
2
layers. As the number of layers increases, charge transport through the vertical WSe
2
p–i–n heterojunctions is characterized by a series of quantum tunneling events; direct tunneling, Fowler–Nordheim tunneling, and Schottky emission tunneling. With optimally selected WSe
2
thickness, our vertical heterojunctions show superb diode characteristics of an unprecedentedly high current density and low turn-on voltages while maintaining good current rectification.
We demonstrate the microwave synthesis of tin oxide (SnO2) nanoparticles and direct deposition on the surface of restacking inhibited reduced graphene oxide (rGO) nanosheets for an application into ...lithium ion battery anodes. The mesoporous rGO-SnO2 nano-composite (G-SnO2), where the SnO2 nanoparticles are intercalated in the layer-by-layer structure of the restacking rGO nanosheets, can be synthesized within 10 min by microwave irradiation, simultaneously promoting the reduction of graphene oxides (GO). The size of SnO2 nanoparticles ranges from 5 to 10 nm and they are highly crystalline structure along with the change in the oxidation states from Sn2+ to Sn4+ in the process of the microwave synthesis. The G-SnO2 anodes show 1200 mAh g−1 at 50 mA g−1 and their specific capacity is preserved up to 1000 mAh g−1 during the 100 cycles. The coulombic efficiency keeps 97% after the 1st cycle and the high specific capacity of 747 mAh g−1 is maintained with 66.3% of capacity retention even when the current density increases from 50 mA g−1 to 300 mA g−1. These results indicate that the improvement of specific capacity, rate capability and cycle stability is attributed to the mesoporous layer-by-layer structure of G-SnO2, where the well-defined SnO2 nanoparticles are deposited on the restacking inhibited rGO nanosheets.
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•Graphene-SnO2 is synthesized within 10 min by microwave irradiation.•SnO2 nanocrystals are uniformly decorated on the graphene sheets.•The restacking of layer-by-layer structured graphene is inhibited.•Graphene-SnO2 shows the high capacity, improving rate and cyclic capabilities.
We aimed to identify the effect of an extended number of neoadjuvant chemotherapy (NAC) cycles on prognosis and surgical morbidity after interval debulking surgery (IDS) in patients with newly ...diagnosed advanced ovarian cancer.
Medical records of patients with advanced ovarian cancer treated with NAC and having undergone IDS were retrospectively reviewed. Clinicopathological factors were compared between two groups: conventional (≤4 cycles) and extended (≥5 cycles) NAC groups. Kaplan-Meier analysis was performed to evaluate progression-free survival (PFS) and overall survival (OS).
A total of 156 patients were included, 112 patients in the conventional group and 44 patients in the extended NAC group. The extended NAC group had a significantly higher frequency of cancer antigen (CA)-125 normalization after NAC (59.1% vs. 33.9%, P = 0.004), a lower rate of bowel surgery (18.2% vs. 34.8%, P = 0.042), and a lower rate of transfusion during or after IDS (36.4% vs. 59.8%, P = 0.008) as compared to the conventional group. The complete cytoreduction rate after IDS was similar between the groups. In multivariate Cox regression analysis for PFS, radiologically stable and progressive disease after NAC (Hazard ratio HR, 1.983; 95% Confidence interval CI, 1.141-3.446; P = 0.015) and gross residual tumor after IDS (HR, 2.054; 95% CI, 1.414-2.983; P < 0.001) were independent risk factors for poor PFS. However, extended NAC cycles were not significantly associated with poor PFS. The median PFS was 19.5 and 16.9 months (P = 0.830), and the 5-year OS was 71.4 and 63.2% (P = 0.677) in the conventional and extended NAC groups, respectively.
Our study showed that extended NAC cycles were not inferior to conventional NAC cycles in terms of survival in patients with advanced ovarian cancer and reduced surgical morbidity such as bowel surgery and transfusion during or after IDS.
The endoplasmic reticulum (ER) is responsible for protein processing. In rapidly proliferating tumor cells, the ER tends to be overloaded with unfolded and misfolded proteins due to high metabolic ...demand. With the limited protein‐folding capacity of the ER, tumor cells often suffer from more ER stress than do normal cells. Thus, cellular stress responses to cope with ER stress, such as the unfolded protein response (UPR) and autophagy, might be more activated in cancer cells than in normal cells. The complex signaling pathways from the UPR to autophagy provide promising druggable targets; a number of UPR/autophagy‐targeted anticancer agents are currently in development in preclinical and clinical studies. In this short review we will discuss the potential anticancer efficacy of modulators of cellular stress responses, especially UPR and autophagy, on the basis of their signaling pathways. In addition, the current developmental status of the UPR/autophagy‐targeted agents will be discussed.
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