102 research outputs found
Assessment of Allergic Rhinitis Websites in Korea
Objectives. The internet has become an important source of medical information and a great amount of information related to allergic rhinitis (AR) is available on the internet. However, the quality of this information is still a matter of debate. Therefore, this study was conducted to assess the AR-related information on Korean websites. Methods. The key word "allergic rhinitis" was entered into 4 popular search engines, and this led to identifying 40 websites. After being categorized according to authorship, the informational value of these websites was evaluated using 4 different assessment tools such as the Journal of the American Medical Association (JAMA) benchmarks, the DISCERN questionnaire, the Allergic Rhinitis and its Impact on Asthma (ARIA) 2008 Update and the Health On the Net (HON) code. Results. The 40 websites containing AR-related information were categorized according to their authorship as Western physician: 20, Oriental physician: 14, commercial: 1, and others: 5. The mean citation frequencies of the JAMA benchmarks and the ARIA 2008 Update concepts was 1.23 out of 4 and 4.33 out of 8, respectively, while the mean DISCERN score was 1.92 out of 5. When the websites were evaluated based on the type of authorship, the mean citation frequencies of the AMA 2008 Update concepts were Western physician: 5.35, Oriental physician: 2.64. Additionally, three websites authored by Western physicians and 13 authored by Oriental physicians contained unreliable information. Among these 16 websites, only 3 websites met the requirements for the HON code "Justification". Conclusion. AR-related information available on Korean websites is of variable quality and not all of the information provided is justifiable. Thus, performing surveillance of the medical information on these websites is necessary. Furthermore, common criteria that can be used to evaluate the websites created by both Western and Oriental physicians are also needed.Bousquet J, 2008, ALLERGY, V63, P8*HLTH NET FDN, 2006, HLTH NET COD COND VESILVA LVE, 2005, BRAZILIAN J OTHORHIN, V71, P590Park HW, 2004, J KOREAN MED SCI, V19, P364Winker MA, 2000, JAMA-J AM MED ASSOC, V283, P1600Charnock D, 1999, J EPIDEMIOL COMMUN H, V53, P105Silberg WM, 1997, JAMA-J AM MED ASSOC, V277, P1244
DJ-1 Null Dopaminergic Neuronal Cells Exhibit Defects in Mitochondrial Function and Structure: Involvement of Mitochondrial Complex I Assembly
DJ-1 is a Parkinson's disease-associated gene whose protein product has a protective role in cellular homeostasis by removing cytosolic reactive oxygen species and maintaining mitochondrial function. However, it is not clear how DJ-1 regulates mitochondrial function and why mitochondrial dysfunction is induced by DJ-1 deficiency. In a previous study we showed that DJ-1 null dopaminergic neuronal cells exhibit defective mitochondrial respiratory chain complex I activity. In the present article we investigated the role of DJ-1 in complex I formation by using blue native-polyacrylamide gel electrophoresis and 2-dimensional gel analysis to assess native complex status. On the basis of these experiments, we concluded that DJ-1 null cells have a defect in the assembly of complex I. Concomitant with abnormal complex I formation, DJ-1 null cells show defective supercomplex formation. It is known that aberrant formation of the supercomplex impairs the flow of electrons through the channels between respiratory chain complexes, resulting in mitochondrial dysfunction. We took two approaches to study these mitochondrial defects. The first approach assessed the structural defect by using both confocal microscopy with MitoTracker staining and electron microscopy. The second approach assessed the functional defect by measuring ATP production, O2 consumption, and mitochondrial membrane potential. Finally, we showed that the assembly defect as well as the structural and functional abnormalities in DJ-1 null cells could be reversed by adenovirus-mediated overexpression of DJ-1, demonstrating the specificity of DJ-1 on these mitochondrial properties. These mitochondrial defects induced by DJ-1mutation may be a pathological mechanism for the degeneration of dopaminergic neurons in Parkinson's disease
TIMP-2 Fusion Protein with Human Serum Albumin Potentiates Anti-Angiogenesis-Mediated Inhibition of Tumor Growth by Suppressing MMP-2 Expression
TIMP-2 protein has been intensively studied as a promising anticancer candidate agent, but the in vivo mechanism underlying its anticancer effect has not been clearly elucidated by previous works. In this study, we investigated the mechanism underlying the anti-tumor effects of a TIMP-2 fusion protein conjugated with human serum albumin (HSA/TIMP-2). Systemic administration of HSA/TIMP-2 effectively inhibited tumor growth at a minimum effective dose of 60 mg/kg. The suppressive effect of HSA/TIMP-2 was accompanied by a marked reduction of in vivo vascularization. The anti-angiogenic activity of HSA/TIMP-2 was directly confirmed by CAM assays. In HSA/TIMP-2-treated tumor tissues, MMP-2 expression was profoundly decreased without a change in MT1-MMP expression of PECAM-1-positive cells. MMP-2 mRNA was also decreased by HSA/TIMP-2 treatment of human umbilical vein endothelial cells. Zymographic analysis showed that HSA/TIMP-2 substantially decreased extracellular pro-MMP-2 activity (94–99% reduction) and moderately decreased active MMP-2 activity (10–24% reduction), suggesting MT1-MMP-independent MMP-2 modulation. Furthermore, HSA/TIMP-2 had no effect on in vitro active MMP-2 activity and in vivo MMP-2 activity. These studies show that HSA/TIMP-2 potentiates anti-angiogenic activity by modulating MMP-2 expression, but not MMP-2 activity, to subsequently suppress tumor growth, suggesting an important role for MMP-2 expression rather than MMP-2 activity in anti-angiogenesis
Minimal information for studies of extracellular vesicles (MISEV2023): From basic to advanced approaches
Extracellular vesicles (EVs), through their complex cargo, can reflect the state of their cell of origin and change the functions and phenotypes of other cells. These features indicate strong biomarker and therapeutic potential and have generated broad interest, as evidenced by the steady year-on-year increase in the numbers of scientific publications about EVs. Important advances have been made in EV metrology and in understanding and applying EV biology. However, hurdles remain to realising the potential of EVs in domains ranging from basic biology to clinical applications due to challenges in EV nomenclature, separation from non-vesicular extracellular particles, characterisation and functional studies. To address the challenges and opportunities in this rapidly evolving field, the International Society for Extracellular Vesicles (ISEV) updates its 'Minimal Information for Studies of Extracellular Vesicles', which was first published in 2014 and then in 2018 as MISEV2014 and MISEV2018, respectively. The goal of the current document, MISEV2023, is to provide researchers with an updated snapshot of available approaches and their advantages and limitations for production, separation and characterisation of EVs from multiple sources, including cell culture, body fluids and solid tissues. In addition to presenting the latest state of the art in basic principles of EV research, this document also covers advanced techniques and approaches that are currently expanding the boundaries of the field. MISEV2023 also includes new sections on EV release and uptake and a brief discussion of in vivo approaches to study EVs. Compiling feedback from ISEV expert task forces and more than 1000 researchers, this document conveys the current state of EV research to facilitate robust scientific discoveries and move the field forward even more rapidly
Channel Shape Effects on Device Instability of Amorphous Indium–Gallium–Zinc Oxide Thin Film Transistors
Channel shape dependency on device instability for amorphous indium–gallium–zinc oxide (a-IGZO) thin film transistors (TFTs) is investigated by using various channel shape devices along with systematic electrical characterization including DC I-V characeristics and bias temperature stress tests. a-IGZO TFTs with various channel shapes such as zigzag, circular, and U-type channels are implemented and their vertical and lateral electric field stress (E-field) effects are systematically tested and analyzed by using an experimental and modeling study. Source and drain (S/D) electrode asymmetry and vertical E-field effects on device instability are neglibible, whereas the lateral E-field effects significantly affect device instability, particularly for zigzag channel shape, compared to circular and U-type TFTs. Moreover, charge trapping time (τ) for zigzag-type a-IGZO TFTs is extracted as 3.8 × 104, which is at least three-times smaller than those of other channel-type a-IGZO TFTs, hinting that local E-field enhancement can critically affect the device reliability. The Technology Computer Aided Design (TCAD) simulation results reveal the locally enhanced E-field at both corner region in the channel in a quantitative mode and its correlation with hemisphere radius (ρ) values
Adaptive Reservoir Management by Reforming the Zone-based Hedging Rules against Multi-year Droughts
© 2022, The Author(s), under exclusive licence to Springer Nature B.V.In this study, the zone-based hedging rule, which is the main operating policy adopted from multipurpose reservoirs in Korea is adjusted to reflect the multi-year droughts caused by climate change. Annual synthetic inflow series with different magnitudes of long memory were generated using the autoregressive fractional integrated moving average (ARFIMA) model. The generated inflow series were then disaggregated into 10-day series and utilized as input variables to derive the alternative hedging rules. The alternative hedging rules from this study were used in adaptive reservoir management by newly updated information. Finally, the performance of the suggested policy is measured in terms of frequency and magnitude under the historical inflow series. As a result, adaptive reservoir management demonstrated improvements in the following terms of the frequency of critical failures (water deficit ratio greater than 30%): 6.14% of the simulation period in the status quo (SQ) policy, and 2.99% in the adaptive management. However, the overall reliability of the reservoir during the simulation horizon was better when operated with the SQ policy (41.19%) than the results from adaptive management (26.42%). Because this result is in a good agreement with the original objective of the hedging rules, the adaptive policy suggested in this study holds promise and may be utilized in further reservoir management with an increase of potential drought risk from climate change.N
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