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1.
Nanotechnology ; 33(32)2022 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-35487198

RESUMO

Dielectric two-dimensional oxide nanosheets are attractive because of their thermal stability and high-k property. However, their atomic structure characterization has been limited since they are easily degraded by electron-beams. This study aimed to investigate the electron-beam induced damage mechanisms for exfoliated Ca2Na2Nb5O16(CNNO) nanosheets. Knock-on damage dominantly occurred at high voltages, leaving short-range order in the final amorphous structure. On the other hand, a series of chemical reactions predominantly occurred at low voltages, resulting in random elemental loss and a fully disordered amorphous structure. This radiolysis was facilitated by insulated CNNO nanosheets that contained a large number of dangling bonds after the chemical solution process. The radiolysis damage kinetics was faster than knock-on damage and induced more elemental loss. Based on our understanding of the electron beam-induced degradation, atomic-scale imaging of the CNNO nanosheets was successfully performed using Cs-corrected scanning transmission electron microscopy at 300 keV with a decreased beam current. This result is of particular significance because understanding of electron-beam damage in exfoliated and insulating 2D oxide sheets could improve identification of their atomic structure using electron microscopy techniques and lead to a practical guide for further extensive characterization of doped elements and layered structures to improve their properties.

2.
Neurosurg Focus ; 51(2): E21, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34333463

RESUMO

OBJECTIVE: With the advancement of 3D modeling techniques and visualization devices, augmented reality (AR)-based navigation (AR navigation) is being developed actively. The authors developed a pilot model of their newly developed inside-out tracking AR navigation system. METHODS: The inside-out AR navigation technique was developed based on the visual inertial odometry (VIO) algorithm. The Quick Response (QR) marker was created and used for the image feature-detection algorithm. Inside-out AR navigation works through the steps of visualization device recognition, marker recognition, AR implementation, and registration within the running environment. A virtual 3D patient model for AR rendering and a 3D-printed patient model for validating registration accuracy were created. Inside-out tracking was used for the registration. The registration accuracy was validated by using intuitive, visualization, and quantitative methods for identifying coordinates by matching errors. Fine-tuning and opacity-adjustment functions were developed. RESULTS: ARKit-based inside-out AR navigation was developed. The fiducial marker of the AR model and those of the 3D-printed patient model were correctly overlapped at all locations without errors. The tumor and anatomical structures of AR navigation and the tumors and structures placed in the intracranial space of the 3D-printed patient model precisely overlapped. The registration accuracy was quantified using coordinates, and the average moving errors of the x-axis and y-axis were 0.52 ± 0.35 and 0.05 ± 0.16 mm, respectively. The gradients from the x-axis and y-axis were 0.35° and 1.02°, respectively. Application of the fine-tuning and opacity-adjustment functions was proven by the videos. CONCLUSIONS: The authors developed a novel inside-out tracking-based AR navigation system and validated its registration accuracy. This technical system could be applied in the novel navigation system for patient-specific neurosurgery.


Assuntos
Realidade Aumentada , Cirurgia Assistida por Computador , Algoritmos , Humanos , Imageamento Tridimensional , Procedimentos Neurocirúrgicos
3.
Nutr Res Pract ; 18(1): 88-97, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38352218

RESUMO

BACKGROUND/OBJECTIVES: Mitigating insulin resistance and hyperglycemia is associated with a decreased risk of diabetic complications. The effect of Daraesoon (shoot of hardy kiwi, Actinidia arguta) on hyperglycemia was investigated using a type 2 diabetes animal model. MATERIALS/METHODS: Seven-week-old db/db mice were fed either an AIN-93G diet or a diet containing 0.4% of a 70% ethanol extract of Daraesoon, whereas db/+ mice were fed the AIN-93G diet for 7 weeks. RESULTS: Consumption of Daraesoon significantly reduced serum glucose and blood glycated hemoglobin levels, along with homeostasis model assessment for insulin resistance in db/db mice. Conversely, Daraesoon elevated the serum adiponectin levels compared to the db/db control group. Furthermore, Daraesoon significantly decreased both serum and hepatic triglyceride levels, as well as serum total cholesterol levels. Additionally, consumption of Daraesoon resulted in decreased hepatic tumor necrosis factor-α and monocyte chemoattractant protein-1 expression. CONCLUSIONS: These results suggest that hypoglycemic effect of Daraesoon is mediated through the improvement of insulin resistance and the downregulation of pro-inflammatory cytokine expression in db/db mice.

4.
Nutr Res Pract ; 18(1): 78-87, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38352215

RESUMO

BACKGROUND/OBJECTIVES: The prevalence of obesity, a worldwide pandemic, has been increasing steadily in Korea. Reports have shown that increased intermuscular adipose tissue (IMAT) is associated with an increased risk of cardiovascular disease, independent of body mass index. However, the relationship between dietary intake and IMAT accumulation in the Korean population remains undetermined. The objective of this study was to evaluate regional fat compartments using advanced magnetic resonance imaging (MRI) techniques. We also aimed to investigate the association between IMAT amounts and dietary intake, including carbohydrate intake, among Korean individuals with obesity. SUBJECTS/METHODS: This cross-sectional study, performed at a medical center in South Korea, recruited 35 individuals with obesity (15 men and 20 women) and classified them into 2 groups according to sex. Anthropometry was performed, and body fat distribution was measured using MRI. Blood parameters, including glucose and lipid profiles, were analyzed using commercial kits. Linear regression analysis was used to test whether the IMAT was associated with daily carbohydrate intake. RESULTS: Carbohydrate intake was positively associated with IMAT in all individuals, with adjustments for age, sex, height, and weight. No significant differences in blood indicators were found between the sexes. CONCLUSIONS: Regardless of sex and age, higher carbohydrate intake was strongly correlated with greater IMAT accumulation. This suggests the need to better understand sex differences and high carbohydrate diet patterns in relation to the association between obesity and metabolic risk, which may help reduce obesity prevalence.

5.
ACS Appl Mater Interfaces ; 16(8): 11076-11083, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38377586

RESUMO

All-solid-state lithium-sulfur batteries (ASSLSBs) have advantageous features, such as high energy, low costs, enhanced safety, and no polysulfide dissolution. However, the use of sulfur as an active material in all-solid-state batteries is difficult because of its ionic and electrical insulating properties. Herein, we introduce a flower-shaped composite material consisting of MoS2 nanoparticles and sulfur, designed to establish interconnected ionic and electrical conduction pathways at the cathode. As a host material, MoS2 nanoparticles with a large specific surface area can coconduct Li ions and electrons, possessing the potential for effectively utilizing sulfur. However, MoS2 nanoparticles are prone to physical-electrochemical isolation by being surrounded by sulfur due to their crumpling property in the process of mixing and impregnation with sulfur. This problem is addressed by mildly milling the MoS2 nanoparticles and sulfur, after which melt diffusion is applied to generate uniform MoS2/sulfur composite materials to establish an interconnected conducting pathway within the composite. A sulfide solid electrolyte (Li6PS5Cl)-based ASSLSB incorporating the proposed MoS2/sulfur composite demonstrates a stable operation over 1000 cycles with a Coulombic efficiency of nearly 100%. This study emphasizes the significance of the structural design of the sulfur composite material on top of the intrinsic properties of the material for high-performance ASSLSBs.

6.
Heliyon ; 10(1): e23288, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38192788

RESUMO

This work aimed to identify the mechanisms by which taurine exerts its anti-obesity effects in the C57BL/6J ob/ob mice model and determine if taurine supplementation increases the amelioration of inflammation and lipogenesis linked genes in the adipose and liver tissues. Three groups of C57BL/6J mice were fed a standard chow diet for a period of 10 weeks the C57BL/6J normal group, the C57BL/6J ob/ob negative control group with no taurine intake and C57BL/6J ob/ob taurine group with taurine intake. Real time PCR was used to examine the gene expression profile in the experimental groups intrascapular brown adipose tissue (BAT), inguinal white adipose tissue (WAT) and liver. TNF-alpha, Ccl2, Adgre and illb genes that are associated with inflammation were found to have varying level of expression in the three tissues. In comparison to BAT and liver these genes were expressed at a much lower level in WAT, with enhanced serum adiponectin levels.

8.
Endocrinol Metab (Seoul) ; 38(5): 482-492, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37846056

RESUMO

This review explores the potential benefits of taurine in ameliorating the metabolic disorders of obesity and type 2 diabetes (T2D), highlighting the factors that bridge these associations. Relevant articles and studies were reviewed to conduct a comprehensive analysis of the relationship between obesity and the development of T2D and the effect of taurine on those conditions. The loss of normal ß-cell function and development of T2D are associated with obesity-derived insulin resistance. The occurrence of diabetes has been linked to the low bioavailability of taurine, which plays critical roles in normal ß-cell function, anti-oxidation, and anti-inflammation. The relationships among obesity, insulin resistance, ß-cell dysfunction, and T2D are complex and intertwined. Taurine may play a role in ameliorating these metabolic disorders through different pathways, but further research is needed to fully understand its effects and potential as a therapeutic intervention.


Assuntos
Diabetes Mellitus Tipo 2 , Resistência à Insulina , Humanos , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/epidemiologia , Taurina/farmacologia , Taurina/uso terapêutico , Obesidade/complicações , Obesidade/tratamento farmacológico , Obesidade/epidemiologia , Glicemia/metabolismo
9.
ACS Nano ; 17(14): 14032-14042, 2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37428961

RESUMO

Lithium-sulfur (Li-S) batteries using Li2S and Li-free anodes have emerged as a potential high-energy and safe battery technology. Although the operation of Li-S full batteries based on Li2S has been demonstrated at room temperature, their effective use at a subzero temperature has not been realized due to the low electrochemical utilization of Li2S. Here, ammonium nitrate (NH4NO3) is introduced as a functional additive that allows Li-S full batteries to operate at -10 °C. The polar N-H bonds in the additive alter the activation pathway of Li2S by inducing the dissolution of the Li2S surface. Then, Li2S with an amorphized surface layer undergoes the modified activation process, which consists of the disproportionation and direct conversion reaction, through which Li2S is efficiently converted into S8. The Li-S full battery using NH4NO3 delivers a reversible capacity and cycling stability over 400 cycles at -10 °C.

10.
Autophagy ; 19(5): 1424-1443, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36250672

RESUMO

ABBREVIATIONS: A:C autophagic membrane:cytosol; ALS amyotrophic lateral sclerosis; ATG4 autophagy related 4; Atg8 autophagy related 8; BafA1 bafilomycin A1; BNIP3L/Nix BCL2 interacting protein 3 like; CALCOCO2/NDP52 calcium binding and coiled-coil domain 2; EBSS Earle's balanced salt solution; GABARAP GABA type A receptor-associated protein; GST glutathione S transferase; HKO hexa knockout; Kd dissociation constant; LIR LC3-interacting region; MAP1LC3/LC3 microtubule associated protein 1 light chain 3; NLS nuclear localization signal/sequence; PE phosphatidylethanolamine; SpHfl1 Schizosaccharomyces pombeorganic solute transmembrane transporter; SQSTM1/p62 SQSTM1/p62; TARDBP/TDP-43 TAR DNA binding protein; TKO triple knockout.


Assuntos
Autofagia , Proteínas de Membrana , Animais , Família da Proteína 8 Relacionada à Autofagia/metabolismo , Proteínas de Membrana/metabolismo , Proteína Sequestossoma-1/metabolismo , Autofagia/genética , Proteínas Reguladoras de Apoptose/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Mamíferos/metabolismo
11.
Sci Total Environ ; 824: 153206, 2022 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-35101509

RESUMO

'Occupant behavior' is the primary mechanism determining indoor particulate concentrations. Various indoor human activities generate particulate matter. Human-building interactions, such as window opening behavior, change the number of outdoor particulate matter introduces to the building. 'Daycare center' where young children spend considerable time has an occupant schedule distinguished from other types of buildings. In the study, we analyzed the effects of occupant behavior on indoor particle concentrations in daycare centers by on-site monitoring. The measurements were performed in four daycare centers located in Gyeonggi-do, South Korea. Optical particle counters(OPS, model 3330, TSI Inc., Shoreview, MN, USA) were used for particulate concentration monitoring. The source strengths of particles resuspended by each human activity were calculated, and their contributions to indoor particle concentrations were evaluated. Further, characteristics of human-building interactions and their corresponding impacts on indoor air quality were also analyzed. Results showed that particle resuspension was greater when occupants were awake (mean, 41.0 particles·min-1) than when they were asleep (mean, 9.2 particles·min-1), and the contribution of occupant status was also higher when awake (37-70% vs. 8-18%) for particles sized (0.3-10.0 µm). Analyzing five detailed human activities, vacuuming (9.8·107 particles·min-1) emitted the highest amount of particulate matter per person, followed by physical activity (4.8·107 particles·min-1), sedentary activity (1.9·107 particles· min-1), meals (1.9·107 particles·min-1), and nap time (8.1·106 particles·min-1). The study suggests that vacuuming should be avoided while children are occupied. This research also shows that children could be exposed to high daily average indoor particulate concentration (up to 1217 particles·cm-3) when windows were opened for an extended period of time while poor outdoor air quality. These results indicate that indoor air quality can be severely degraded by opening windows without considering the level of outdoor particle concentration.


Assuntos
Poluentes Atmosféricos , Poluição do Ar em Ambientes Fechados , Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Criança , Pré-Escolar , Poeira , Monitoramento Ambiental/métodos , Humanos , Tamanho da Partícula , Material Particulado/análise
12.
Metab Syndr Relat Disord ; 20(10): 551-557, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36269325

RESUMO

Background: Obesity is commonly associated with a high risk of metabolic disorders, and obesity-related metabolic abnormalities are affected by some specific obesity phenotypes, regional fat distribution, and body mass index. However, few studies have investigated the relationship between obesity phenotypes and regional fat distribution in Korean subjects. This study aimed to assess regional fat distribution by gender using magnetic resonance imaging (MRI), and to identify a link between fat distribution and metabolic disorders in Korean subjects. Methods: This study included 35 Korean subjects (20 women, 15 men) who were classified into two groups by gender, and further divided into two groups based on their obesity phenotype: a metabolically abnormal obesity (MAO) and metabolically healthy obesity (MHO) group. Fat distribution was measured using MRI. The blood parameters were measured using a commercially available kit. Results: Women in the MAO group had more risk factors for metabolic abnormalities than those in the MHO group. Serum glucose, triglyceride, and high-density lipoprotein cholesterol (HDL-C) levels were also significantly higher in women with MAO than in those with MHO. The intermuscular adipose tissue (IMAT) of women with MAO was significantly higher than that of women with MHO. Serum HDL-C level was negatively correlated with IMAT, whereas leptin showed a positive correlation with IMAT in all subjects. Conclusions: Metabolic abnormalities according to obesity phenotype posed a higher risk in women than that in men. These findings suggest that an understanding of gender differences in relation to the association between obesity and metabolic risk would be helpful to reduce the prevalence of obesity.


Assuntos
Doenças Metabólicas , Obesidade Metabolicamente Benigna , Humanos , Feminino , População do Leste Asiático , Obesidade/diagnóstico por imagem , Obesidade/epidemiologia , Obesidade/complicações , Tecido Adiposo/metabolismo , Obesidade Metabolicamente Benigna/complicações , Fenótipo , Doenças Metabólicas/metabolismo , Imageamento por Ressonância Magnética , Monoaminoxidase/metabolismo
13.
IEEE J Transl Eng Health Med ; 10: 4900507, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35937462

RESUMO

OBJECTIVE: Extended Reality (XR) is a simultaneous combination of the virtual and real world. This paper presents the details of the framework and development methods for an XR basic life support (XR-BLS) simulator, as well as the results of an expert usability survey. METHODS: The XR-BLS simulator was created by employing a half-torso manikin in a virtual reality environment and using BLS education data that is in line with the 2020 American Heart Association guidelines. A head-mounted display (HMD) and hand-tracking device were used to perform chest compressions and ventilation and to enable the use of an automated external defibrillator in a virtual environment. A usability study of the XR-BLS simulator through an expert survey was also conducted. The survey consisted of a total of 8 items: 3, 2, and 2 questions about the ease of use of XR-BLS, delivery of training, and artificial intelligence (AI) instructor in the simulator, respectively. RESULTS: The XR simulator was developed, and the expert survey showed that it was easy to use, the BLS training was well delivered, and the interaction with the AI instructor was clear and understandable. DISCUSSION/CONCLUSION: The XR-BLS simulator is useful as it can conduct BLS education without requiring instructors and trainees to gather.


Assuntos
Reanimação Cardiopulmonar , Inteligência Artificial , Reanimação Cardiopulmonar/educação , Desfibriladores , Avaliação Educacional , Manequins , Estados Unidos
14.
J Med Food ; 24(10): 1092-1099, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34668765

RESUMO

Obesity, insulin resistance, and oxidative stress are important risk factors for nonalcoholic fatty liver disease (NAFLD). This study aimed at determining the beneficial effects of myricetin against NAFLD in ob/ob mice. C57BL/6-Lepob/ob mice (n = 21) were fed an AIN-93G diet (ob/ob control group) or diet containing 0.04% (low myricetin; LMTN group) or 0.08% (high myricetin; HMTN group) myricetin, and lean heterozygous littermates (lean control group, n = 7) were fed AIN-93G diet for 10 weeks. HMTN consumption significantly lowered serum glucose levels and homeostasis model assessment for insulin resistance values in ob/ob mice. In addition to reducing serum triglyceride (TG) and cholesterol levels, HMTN significantly decreased total hepatic lipid and TG levels partly through downregulation of carbohydrate response element-binding protein and sterol regulatory element-binding protein 1c expression. The reduction in the levels of hepatic thiobarbituric acid reactive substances by HMTN likely resulted from the elevation of nuclear factor erythroid-2-related factor 2 expression. Tumor necrosis factor-α and monocyte chemoattractant protein 1 expressions were reduced by LMTN and HMTN, and HMTN also decreased interleukin-6 expression. These results suggest that myricetin has beneficial effects against NAFLD by regulating the expression of transcription factors of hepatic lipid metabolism, the antioxidant system, and pro-inflammatory cytokines.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Animais , Flavonoides , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/genética
15.
Nutr Res Pract ; 15(4): 456-467, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34349879

RESUMO

BACKGROUND/OBJECTIVES: The prevalence of morbid obesity in Korean women has consistently been increasing, while the overall prevalence rate of obesity in Korean women seems to be stable. In addition to bariatric surgery, intragastric balloons (IGBs), as a nonsurgical therapy, have been reported to be effective in weight loss. However, the beneficial effects of IGB in Korean women with obesity have not been fully investigated. The aim of this study was to evaluate the changes in fat mass in Korean women with obesity who had undergone IGB treatment for 6 mon. SUBJECTS/METHODS: Seventy-four women with obesity (body mass index [BMI] ≥ 25.0 kg/m2) were recruited. Clinical data, including general information, comorbidities with obesity, anthropometric data, and changes in the body fat composition before and after IGB treatment, were obtained from the subjects. RESULTS: Most subjects had one or more comorbidities, such as osteoarthropathy and woman's disease, and had poor eating behaviors, including irregular mealtimes, eating quickly, and frequent overeating. Body composition measurements showed that weight, fat mass, and waist-hip circumference ratio decreased significantly at 6 mon after IGB treatment. In particular, women with morbid obesity (BMI ≥ 30 kg/m2) showed 33% excess weight loss. There was no significant difference in skeletal muscle mass and mineral contents after IGB treatment. CONCLUSIONS: This study suggested that 6 mon of IGB treatment can be a beneficial treatment for obesity without muscle mass and bone mineral loss.

16.
J Med Food ; 23(1): 37-42, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31855493

RESUMO

The association between obesity and erythrocyte fatty acids (FAs) has been suggested; however, there have been no studies on the effects of onion peel extract (OPE) on the composition of erythrocyte FAs. This study aimed to investigate the effects of OPE on the composition of erythrocyte FAs in overweight and obese subjects. This was a randomized, double-blind, and placebo-controlled trial conducted in overweight and obese Korean subjects. The placebo and OPE groups were taking placebo capsule or OPE capsule twice per day for 12 weeks. Body composition and fat distribution were measured using dual-energy X-ray absorptiometry. The OPE group showed significantly reduced body weight, body mass index, body fat mass, and percentage of body fat mass. After 12 weeks, eicosapentaenoic acid and monounsaturated FAs of the placebo group were significantly lower at baseline. Consumption of OPE ameliorated the decreasing polyunsaturated n-3 polyunsaturated FA (PUFA) n-3 and increasing PUFA n-6, which prevented an increased n-6/n-3 ratio. The changes in arm fat percentage (ARFATP), trunk fat percentage, and total fat percentage (FATP) were negatively correlated with the change in PUFA n-3. In addition, increased erythrocyte docosahexaenoic acid was associated with decreased ARFATP and FATP. These results suggest that OPE has beneficial effects on obesity by regulating erythrocyte n-6/n-3 ratio and preventing fat accumulation in various body regions.


Assuntos
Membrana Eritrocítica/química , Ácidos Graxos Ômega-3/química , Obesidade/sangue , Cebolas/química , Sobrepeso/sangue , Extratos Vegetais/farmacologia , Adiposidade , Adulto , Índice de Massa Corporal , Peso Corporal , Método Duplo-Cego , Ácidos Graxos Ômega-6/química , Humanos , Pessoa de Meia-Idade , República da Coreia
17.
Clin Nutr Res ; 9(3): 205-212, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32789150

RESUMO

The relationship between phase angle (PhA) of bioelectrical impedance analysis (BIA) and glycemic parameters in diabetes mellitus (DM) patients has not been well studied. To evaluate the prognostic value of the PhA from BIA as a glycemic marker, we investigated the relationship of PhA with various variables such as age, body mass index (BMI), and glycemic parameters in Korean patients with type 2 DM (T2DM). We evaluated the anthropometric data, body composition, glycemic parameters, and PhA of 321 T2DM patients aged 30-83 years. The patients were classified by sex into men (n = 133) and women (n = 188). General linear models identified the independent effects of PhA after covarying for age, sex and BMI. The PhA, body cell mass (BCM), extracellular mass (ECM), lean body mass, intracellular water (ICW), extracellular water (ECW), total body water (TBW), fasting blood glucose, and hemoglobin A1c (HbA1c) of T2DM Korean patients were significantly higher in men than in women. However, fat mass, ECM/BCM, ECW/ICW, ECW/TBW, and serum insulin were significantly higher in women than in men. Statistically significant independent associations were observed between PhA and age, BCM, ECM, ECM/BCM, ICW, ECW, ECW/ICW, and ECW/TBW for both sexes. There was no significant association between PhA and BMI the patients. Glycemic parameters, such as HbA1c and fasting blood glucose were independently associated with PhA. These results suggest that PhA could be an indicator for assessing ability to control fasting blood glucose in T2DM patients in Korea.

18.
Cell Death Dis ; 11(11): 952, 2020 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-33154354

RESUMO

C-terminal fragments of Tar DNA-binding protein 43 (TDP-43) have been identified as the major pathological protein in several neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). However, how they affect cellular toxicity and neurodegeneration, including the modulation process remains unknown. This study revealed that the C-terminal fragment of TDP-43 (TDP-25) was localized primarily to mitochondria and caused abnormal mitochondrial morphology, inducing Parkin-mediated mitophagy. Also, we discovered that the knockdown of selective autophagy receptors, such as TAX1BP, Optineurin, or NDP52 caused TDP-25 accumulation, indicating that TDP-25 was degraded by mitophagy. Interestingly, myosin IIB, a nonmuscle type of myosin and actin-based motor protein, is mostly colocalized to TDP-25 associated with abnormal mitochondria. In addition, myosin IIB inhibition by siRNA or blebbistatin induced mitochondrial accumulation of insoluble TDP-25 and Tom20, and reduced neuronal cell viability. Our results suggest a novel role of myosin IIB in mitochondrial degradation of toxic TDP-25. Therefore, we proposed that regulating myosin IIB activity might be a potential therapeutic target for neurodegenerative diseases associated with TDP-43 pathology.


Assuntos
Esclerose Lateral Amiotrófica/patologia , Proteínas de Ligação a DNA/metabolismo , Mitocôndrias/patologia , Mitofagia , Miosina não Muscular Tipo IIB/metabolismo , Fragmentos de Peptídeos/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/metabolismo , Proteínas de Ligação a DNA/genética , Células HEK293 , Humanos , Mitocôndrias/genética , Mitocôndrias/metabolismo , Miosina não Muscular Tipo IIB/genética , Fragmentos de Peptídeos/genética , Ubiquitina-Proteína Ligases/genética
19.
Nat Commun ; 11(1): 4212, 2020 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-32839469

RESUMO

Phosphatases, together with kinases and transcription factors, are key components in cellular signalling networks. Here, we present a systematic functional analysis of the phosphatases in Cryptococcus neoformans, a fungal pathogen that causes life-threatening fungal meningoencephalitis. We analyse 230 signature-tagged mutant strains for 114 putative phosphatases under 30 distinct in vitro growth conditions, revealing at least one function for 60 of these proteins. Large-scale virulence and infectivity assays using insect and mouse models indicate roles in pathogenicity for 31 phosphatases involved in various processes such as thermotolerance, melanin and capsule production, stress responses, O-mannosylation, or retromer function. Notably, phosphatases Xpp1, Ssu72, Siw14, and Sit4 promote blood-brain barrier adhesion and crossing by C. neoformans. Together with our previous systematic studies of transcription factors and kinases, our results provide comprehensive insight into the pathobiological signalling circuitry of C. neoformans.


Assuntos
Cryptococcus neoformans/genética , Proteínas Fúngicas/genética , Perfilação da Expressão Gênica/métodos , Genoma Fúngico/genética , Estudo de Associação Genômica Ampla/métodos , Monoéster Fosfórico Hidrolases/genética , Animais , Análise por Conglomerados , Criptococose/microbiologia , Cryptococcus neoformans/patogenicidade , Feminino , Proteínas Fúngicas/classificação , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica , Camundongos Endogâmicos , Monoéster Fosfórico Hidrolases/classificação , Monoéster Fosfórico Hidrolases/metabolismo , Fosfotransferases/classificação , Fosfotransferases/genética , Fosfotransferases/metabolismo , Transdução de Sinais/genética , Termotolerância/genética , Fatores de Transcrição/classificação , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Virulência/genética
20.
Appl Microsc ; 49(1): 4, 2019 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-33580273

RESUMO

We applied the advanced bitmap-assisted patterning function of focused ion beam to fabricate microscale sculpture of the 'BangTanSoNyeonDan' known as BTS members, the world-wide famous K-pop boyband. With the help of an electron microscope, you can carve your idols on your accessories at micro scale. Fun applications of electron microscopes are not limited to science.

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