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1.
Sensors (Basel) ; 21(21)2021 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-34770359

RESUMO

Non-orthogonal multiple access (NOMA) has a key feature that the cell-center user (CCU) has prior information about the messages of the cell-edge user (CEU) in the same user-pair. It means that CCU can be used for retransmission when the CEU requests retransmission. As ultra-reliability and low-latency communication (URLLC) requires high-reliability constraints (e.g., 99.999%), using CCU for retransmission can be useful to satisfy the reliability constraint. In this study, to ensure the reliability of CEU, cooperative retransmission (CR) scheme for downlink NOMA systems is proposed. And the CR scheme is evaluated with Block error rate (BLER) considering reliability and with packet loss rate (PLR) in terms of reliability and latency constraints. And the evaluation results showed that the proposed CR scheme can satisfy the target BLER for URLLC low SNR compared to the conventional retransmission scheme, and showed the improved PLR compared to the conventional retransmission scheme in low SNRs.


Assuntos
Noma , Comunicação , Redes de Comunicação de Computadores , Humanos , Reprodutibilidade dos Testes , Razão Sinal-Ruído
2.
Int J Mol Sci ; 22(13)2021 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-34202606

RESUMO

Cancer is heterogeneous among patients, requiring a thorough understanding of molecular subtypes and the establishment of therapeutic strategies based on its behavior. Gastric cancer (GC) is adenocarcinoma with marked heterogeneity leading to different prognoses. As an effort, we previously identified a stem-like subtype, which is prone to metastasis, with the worst prognosis. Here, we propose FNBP1 as a key to high-level cell motility, present only in aggressive GC cells. FNBP1 is also up-regulated in both the GS subtype from the TCGA project and the EMT subtype from the ACRG study, which include high portions of diffuse histologic type. Ablation of FNBP1 in the EMT-type GC cell line brought changes in the cell periphery in transcriptomic analysis. Indeed, loss of FNBP1 resulted in the loss of invasive ability, especially in a three-dimensional culture system. Live imaging indicated active movement of actin in FNBP1-overexpressed cells cultured in an extracellular matrix dome. To find the transcription factor which drives FNBP1 expression in an EMT-type GC cell line, the FNBP1 promoter region and DNA binding motifs were analyzed. Interestingly, the Sp1 motif was abundant in the promoter, and pharmacological inhibition and knockdown of Sp1 down-regulated FNBP1 promoter activity and the transcription level, respectively. Taken together, our results propose Sp1-driven FNBP1 as a key molecule explaining aggressiveness in EMT-type GC cells.


Assuntos
Transição Epitelial-Mesenquimal/genética , Proteínas de Ligação a Ácido Graxo/genética , Regulação Neoplásica da Expressão Gênica , Fator de Transcrição Sp1/metabolismo , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Sequência de Bases , Sítios de Ligação , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células , Matriz Extracelular , Proteínas de Ligação a Ácido Graxo/metabolismo , Perfilação da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Invasividade Neoplásica , Motivos de Nucleotídeos , Neoplasias Gástricas/patologia
3.
Int J Mol Sci ; 22(13)2021 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-34202759

RESUMO

The use of porous three-dimensional (3D) composite scaffolds has attracted great attention in bone tissue engineering applications because they closely simulate the major features of the natural extracellular matrix (ECM) of bone. This study aimed to prepare biomimetic composite scaffolds via a simple 3D printing of gelatin/hyaluronic acid (HA)/hydroxyapatite (HAp) and subsequent biomineralization for improved bone tissue regeneration. The resulting scaffolds exhibited uniform structure and homogeneous pore distribution. In addition, the microstructures of the composite scaffolds showed an ECM-mimetic structure with a wrinkled internal surface and a porous hierarchical architecture. The results of bioactivity assays proved that the morphological characteristics and biomineralization of the composite scaffolds influenced cell proliferation and osteogenic differentiation. In particular, the biomineralized gelatin/HA/HAp composite scaffolds with double-layer staggered orthogonal (GEHA20-ZZS) and double-layer alternative structure (GEHA20-45S) showed higher bioactivity than other scaffolds. According to these results, biomineralization has a great influence on the biological activity of cells. Hence, the biomineralized composite scaffolds can be used as new bone scaffolds in bone regeneration.


Assuntos
Regeneração Óssea , Durapatita , Gelatina , Ácido Hialurônico , Impressão Tridimensional , Engenharia Tecidual , Tecidos Suporte , Biomineralização , Diferenciação Celular , Fenômenos Químicos , Durapatita/química , Módulo de Elasticidade , Gelatina/química , Análise Espectral , Tecidos Suporte/química , Viscosidade
5.
J Hepatol ; 75(3): 514-523, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33892010

RESUMO

BACKGROUND & AIMS: Non-alcoholic fatty liver disease (NAFLD) poses an increasing clinical burden. Genome-wide association studies have revealed a limited contribution of genomic variants to the disease, requiring alternative but robust approaches to identify disease-associated variants and genes. We carried out a disease-specific expression quantitative trait loci (eQTL) screen to identify novel genetic factors that specifically act on NAFLD progression on the basis of genotype. METHODS: We recruited 125 Korean patients (83 with biopsy-proven NAFLD and 42 without NAFLD) and performed eQTL analyses using 21,272 transcripts and 3,234,941 genotyped and imputed single nucleotide polymorphisms. We then selected eQTLs that were detected only in the NAFLD group, but not in the control group (i.e., NAFLD-eQTLs). An additional cohort of 162 Korean individuals with NAFLD was used for replication. The function of the selected eQTL toward NAFLD development was validated using HepG2, primary hepatocytes and NAFLD mouse models. RESULTS: The NAFLD-specific eQTL screening yielded 242 loci. Among them, AGXT2, encoding alanine-glyoxylate aminotransferase 2, displayed decreased expression in patients with NAFLD homozygous for the non-reference allele of rs2291702, compared to no-NAFLD individuals with the same genotype (p = 4.79 × 10-6). This change was replicated in an additional 162 individuals, yielding a combined p value of 8.05 × 10-8 from a total of 245 patients with NAFLD and 42 controls. Knockdown of AGXT2 induced palmitate-overloaded hepatocyte death by increasing endoplasmic reticulum stress, and exacerbated NAFLD diet-induced liver fibrosis in mice, while overexpression of AGXT2 attenuated liver fibrosis and steatosis. CONCLUSIONS: We identified a new molecular role for AGXT2 in NAFLD. Our overall approach will serve as an efficient tool for uncovering novel genetic factors that contribute to liver steatosis and fibrosis in patients with NAFLD. LAY SUMMARY: Elucidating causal genes for non-alcoholic fatty liver disease (NAFLD) has been challenging due to limited tissue availability and the polygenic nature of the disease. Using liver and blood samples from 125 Korean individuals (83 with NAFLD and 42 without NAFLD), we devised a new analytic method to identify causal genes. Among the candidates, we found that AGXT2-rs2291702 protects against liver fibrosis in a genotype-dependent manner with the potential for therapeutic interventions. Our approach enables the discovery of causal genes that act on the basis of genotype.

7.
Nanotechnology ; 32(19): 190001, 2021 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-33524956

RESUMO

Adhesion of carbon nanotube (CNT) onto a cathode substrate is very crucial for field electron emitters that are operating under high electric fields. As a supporting precursor of CNT field emitters, we adopted silicon carbide (SiC) nano-particle fillers with Ni particles and then enhanced interfacial reactions onto Kovar-alloy substrates through the optimized wet pulverization process of SiC aggregates for reliable field electron emitters. As-purchased SiC aggregates were efficiently pulverized from 20 to less than 1 micro-meter in a median value (D50). CNT pastes for field emitters were distinctively formulated by a mixing process of the pulverized SiC aggregates and pre-dispersed CNTs. X-ray photoelectron spectroscopy studies showed that the optimally pulverized SiC-CNT paste-emitter had a stronger Si 2p3/2 signal in the Ni2Si phase than the as-purchased one. The Si 2p3/2 signal would represent interfacial reaction of the SiC nano-particle onto Ni from the CNT paste and the Kovar substrate, forming the supporting layer for CNT emitters. The optimal paste-emitter even in a vacuum-sealed tube exhibited a highly reliable field emission current with a high current density of 100 mA cm-2 for over 50 h along with good reproducibility. The enhanced interfacial reaction of SiC filler onto the metal substrates could lead to highly reliable field electron emitters for vacuum electronic devices.

8.
Diabetes ; 70(1): 182-195, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33046512

RESUMO

Becn1/Beclin-1 is a core component of the class III phosphatidylinositol 3-kinase required for autophagosome formation and vesicular trafficking. Although Becn1 has been implicated in numerous diseases such as cancer, aging, and neurodegenerative disease, the role of Becn1 in white adipose tissue and related metabolic diseases remains elusive. In this study, we show that adipocyte-specific Becn1 knockout mice develop severe lipodystrophy, leading to adipose tissue inflammation, hepatic steatosis, and insulin resistance. Ablation of Becn1 in adipocytes stimulates programmed cell death in a cell-autonomous manner, accompanied by elevated endoplasmic reticulum (ER) stress gene expression. Furthermore, we observed that Becn1 depletion sensitized mature adipocytes to ER stress, leading to accelerated cell death. Taken together, these data suggest that adipocyte Becn1 would serve as a crucial player for adipocyte survival and adipose tissue homeostasis.


Assuntos
Adipócitos/metabolismo , Tecido Adiposo Branco/metabolismo , Proteína Beclina-1/metabolismo , Resistência à Insulina/genética , Lipodistrofia/metabolismo , Doenças Metabólicas/metabolismo , Animais , Proteína Beclina-1/genética , Fígado Gorduroso/genética , Fígado Gorduroso/metabolismo , Homeostase/genética , Inflamação/genética , Inflamação/metabolismo , Lipodistrofia/genética , Doenças Metabólicas/genética , Camundongos , Camundongos Knockout
9.
Sci Rep ; 10(1): 18166, 2020 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-33097799

RESUMO

Stress hyperglycemia and insulin resistance are evolutionarily conserved metabolic adaptations to severe injury including major trauma, burns, or hemorrhagic shock (HS). In response to injury, the neuroendocrine system increases secretion of counterregulatory hormones that promote rapid mobilization of nutrient stores, impair insulin action, and ultimately cause hyperglycemia, a condition known to impair recovery from injury in the clinical setting. We investigated the contributions of adipocyte lipolysis to the metabolic response to acute stress. Both surgical injury with HS and counterregulatory hormone (epinephrine) infusion profoundly stimulated adipocyte lipolysis and simultaneously triggered insulin resistance and hyperglycemia. When lipolysis was inhibited, the stress-induced insulin resistance and hyperglycemia were largely abolished demonstrating an essential requirement for adipocyte lipolysis in promoting stress-induced insulin resistance. Interestingly, circulating non-esterified fatty acid levels did not increase with lipolysis or correlate with insulin resistance during acute stress. Instead, we show that impaired insulin sensitivity correlated with circulating levels of the adipokine resistin in a lipolysis-dependent manner. Our findings demonstrate the central importance of adipocyte lipolysis in the metabolic response to injury. This insight suggests new approaches to prevent insulin resistance and stress hyperglycemia in trauma and surgery patients and thereby improve outcomes.


Assuntos
Adipócitos/metabolismo , Hiperglicemia/metabolismo , Lipólise/fisiologia , Choque Hemorrágico/complicações , Ferida Cirúrgica/complicações , Animais , Modelos Animais de Doenças , Epinefrina/administração & dosagem , Epinefrina/metabolismo , Feminino , Humanos , Hiperglicemia/sangue , Hiperglicemia/etiologia , Hiperglicemia/fisiopatologia , Insulina/metabolismo , Resistência à Insulina/fisiologia , Lipase/genética , Lipase/metabolismo , Masculino , Camundongos , Camundongos Knockout , Resistina/sangue , Resistina/metabolismo , Choque Hemorrágico/sangue , Choque Hemorrágico/metabolismo , Choque Hemorrágico/fisiopatologia , Ferida Cirúrgica/sangue , Ferida Cirúrgica/metabolismo , Ferida Cirúrgica/fisiopatologia
10.
Pancreatology ; 20(8): 1587-1591, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33008750

RESUMO

BACKGROUND: Early diagnosis of severe acute pancreatitis (AP) is important to reduce morbidity and mortality. We investigated the association between the triglyceride and glucose index (TyG index) and the prognosis of severe AP (SAP). METHODS: The TyG index was calculated as: ln [fasting triglycerides (mg/dL) x fasting plasma glucose (mg/dL)]/2. Multivariable logistic regression analyses were used to investigate the independent association between the TyG index and the severity of AP. RESULTS: In this study, 373 patients with AP were recruited from three hospitals. The TyG index was higher in the SAP group than in the non-SAP group. Further, the TyG index was higher than in patients admitted to an intensive care unit and those who died of AP. The TyG index was an independent predictive factor for SAP (odds ratio 7.14, 95% confidence interval 2.80-18.19). The area under the curve increased significantly, from 0.738 to 0.830, after adding the TyG index to a predictive SAP model. CONCLUSIONS: Our findings suggest that the TyG index is an independent prognostic factor in patients with AP and could be used as a simple prognostic indicator for SAP.


Assuntos
Glicemia , Pancreatite , Triglicerídeos , Biomarcadores/sangue , Diagnóstico Precoce , Glucose , Humanos , Pancreatite/diagnóstico , Prognóstico , Triglicerídeos/sangue
11.
J Clin Neurol ; 16(4): 633-645, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33029970

RESUMO

BACKGROUND AND PURPOSE: The Movement Disorder Society-Sponsored Revision of the Unified Parkinson's Disease Rating Scale (MDS-UPDRS) is widely used for estimating the symptoms of Parkinson's disease. Translation and validation of the MDS-UPDRS is necessary for non-English speaking countries and regions. The aim of this study was to validate the Korean version of the MDS-UPDRS. METHODS: Altogether, 362 patients in 19 centers were recruited for this study. We translated the MDS-UPDRS to Korean using the translation-back translation method and cognitive pretesting. We performed both confirmatory and exploratory factor analyses to validate the scale. We calculated the comparative fit index (CFI) for confirmatory factor analysis, and used unweighted least squares for exploratory factor analysis. RESULTS: The CFI was higher than 0.90 for all parts of the scale. Exploratory factor analysis also showed that the Korean MDS-UPDRS has the same number of factors in each part as the English version. CONCLUSIONS: The Korean MDS-UPDRS has the same overall structure as the English MDS-UPDRS. Our translated scale can be designated as the official Korean MDS-UPDRS.

12.
J Clin Med ; 9(9)2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32942753

RESUMO

BACKGROUND: The atherogenic index of plasma (AIP) reflects the levels of triglycerides (TG) and high-density lipoprotein (HDL) cholesterol. The purpose of this study was to assess the relationship between the AIP and severe acute pancreatitis (SAP). MATERIALS AND METHODS: Patients with acute pancreatitis (AP) were prospectively enrolled from March 2015 to June 2019. The severity of AP was classified according to the 2012 revised Atlanta classification. Mild and moderately severe AP were categorized as non-SAP. The AIP is calculated as log(TG/HDL). RESULTS: A total of 323 patients were enrolled. The etiologies of AP were gallstone in 171 patients (52.9%), alcohol in 122 patients (37.8%), and hypertriglyceridemia in 30 patients (9.3%). Twenty-four patients (7.4%) were classified as SAP. The AIP was significantly higher in the SAP group compared to the non-SAP group (p < 0.001). The AIP was positively correlated with the Atlanta classification (R = 0.256, p < 0.001). In multivariate analysis, the AIP was found to be an independent predictive factor for SAP (OR = 4.571; CI = 1.913-10.922; p = 0.001). CONCLUSIONS: The AIP is a potential biomarker for the prediction of SAP in clinical practice. This result provides that impaired lipid metabolism is associated with the severity of pancreatitis.

13.
Data Brief ; 32: 106186, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32904311

RESUMO

To secure the safety for industrial applications of plant essential oils, it is necessary to determine the inhibitory concentration and inhibitory mechanism of cell proliferation in skin cells and lung cells. Considering inhalation through the respiratory system and skin contact of humans with essential oils, we used human lung cancer cells A549 and human skin fibroblasts Detroit 551 cells for all experiments. In this study, we examined IC50 values and protein levels of cell cycle markers (cyclin A, cyclin B, cyclin D, and cyclin E) and apoptosis marker (caspase-3) after exposure to 10 plant essential oils, including Dendranthema indicum (L.) Des Moul, Peucedanum japonicum Thunb, Dendranthema zawadskii var. latilobum (Maxim.) Kitam, Agastache rugosa (Fisch.&Mey.) Kuntze, Vitex rotundifolia L.f, Pinus rigida Mill; Orixa japonica Thunb, Pinus strobus L, Chamaecyparis pisifera (Siebold et Zucc.) Endl. var. filifera Beissn. et Hochst, and Citrus sunki Hort. ex Tanaka. After the treatment of A549 and Detroit 551 cells to varying concentrations of the 10 plant essential oils, IC50 values were determined by CCK analysis, whereas protein expressions of the four cyclins and caspase-3 were identified by Western blotting analysis. We believe that by examining the degree and mechanism of cell proliferation inhibition exerted by essential oils on skin and lung cells of humans, data obtained in this study can provide guidelines for the industrial application of plant essential oils.

14.
Transl Vis Sci Technol ; 9(4): 1, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32818089

RESUMO

Purpose: Continuous monitoring of elevated intraocular pressure and timely drug delivery for successful treatment of glaucoma are necessary to reduce intraocular pressure (IOP), which shows wide variations across the circadian pattern and in response to medication. This in vivo study presents a new contact lens-based method of optical IOP measurement or temperature-triggered drug elution. Methods: A contact lens with moiré patterns of concentric circles measures the changes in eyeball diameter of a rabbit glaucoma model due to changes in IOP by superimposing a camera-captured image onto the micro pattern of the contact lens with a computer-assisted virtual reference image. Drug elution from the nanoporous bicontinuous microemulsion contact lens (BME-CL) into the eye of the rabbit was triggered by a temperature-responsive nanogel drug carrier. Results: The moiré pattern change on the contact lens was proportional to the IOP increase in the rabbit eye either ex vivo or in vivo and was also correlated with imaging-based alterations in the anterior chamber angle at a range of IOP values (3-40 mm Hg). The cumulative drug absorbed reached as high as 10.6 µg/mL aqueous humor until 7 days after wearing the BME-CL, and a 33% decrease in IOP was observed at 3 hours after drug elution. Conclusions: The results suggest that continuous measurement and treatment of elevated IOP are feasible using moiré pattern-inscribed and thermosensitive drug-eluting contact lenses, respectively. Translational Relevance: Pressure-sensing or thermosensitive contact lenses enable monitoring IOP or drug release triggered by body temperature for the treatment of glaucoma patients.


Assuntos
Lentes de Contato , Tonometria Ocular , Animais , Liberação Controlada de Fármacos , Humanos , Pressão Intraocular , Coelhos , Temperatura
15.
J Am Soc Nephrol ; 31(6): 1191-1211, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32381600

RESUMO

BACKGROUND: Mutations in ADCK4 (aarF domain containing kinase 4) generally manifest as steroid-resistant nephrotic syndrome and induce coenzyme Q10 (CoQ10) deficiency. However, the molecular mechanisms underlying steroid-resistant nephrotic syndrome resulting from ADCK4 mutations are not well understood, largely because the function of ADCK4 remains unknown. METHODS: To elucidate the ADCK4's function in podocytes, we generated a podocyte-specific, Adck4-knockout mouse model and a human podocyte cell line featuring knockout of ADCK4. These knockout mice and podocytes were then treated with 2,4-dihydroxybenzoic acid (2,4-diHB), a CoQ10 precursor analogue, or with a vehicle only. We also performed proteomic mass spectrometry analysis to further elucidate ADCK4's function. RESULTS: Absence of Adck4 in mouse podocytes caused FSGS and albuminuria, recapitulating features of nephrotic syndrome caused by ADCK4 mutations. In vitro studies revealed that ADCK4-knockout podocytes had significantly reduced CoQ10 concentration, respiratory chain activity, and mitochondrial potential, and subsequently displayed an increase in the number of dysmorphic mitochondria. However, treatment of 3-month-old knockout mice or ADCK4-knockout cells with 2,4-diHB prevented the development of renal dysfunction and reversed mitochondrial dysfunction in podocytes. Moreover, ADCK4 interacted with mitochondrial proteins such as COQ5, as well as cytoplasmic proteins such as myosin and heat shock proteins. Thus, ADCK4 knockout decreased the COQ complex level, but overexpression of ADCK4 in ADCK4-knockout podocytes transfected with wild-type ADCK4 rescued the COQ5 level. CONCLUSIONS: Our study shows that ADCK4 is required for CoQ10 biosynthesis and mitochondrial function in podocytes, and suggests that ADCK4 in podocytes stabilizes proteins in complex Q in podocytes. Our study also suggests a potential treatment strategy for nephrotic syndrome resulting from ADCK4 mutations.


Assuntos
Hidroxibenzoatos/farmacologia , Proteínas Quinases/fisiologia , Ubiquinona/análogos & derivados , Animais , Estabilidade Enzimática , Glomerulosclerose Segmentar e Focal/etiologia , Células HEK293 , Humanos , Metiltransferases/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/fisiologia , Proteínas Mitocondriais/metabolismo , Podócitos/enzimologia , Ubiquinona/metabolismo
16.
Opt Express ; 28(10): 15392-15406, 2020 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-32403567

RESUMO

An optical see-through (OST) display is affected more severely by ambient light than any other type of displays when placed in an outdoor environment with bright illuminance because of its transparency and thus, its inherent color distortion can worsen. It is hard to directly apply existing gamut mapping methods to an OST display because of its morphological gamut characteristic and the effect of ambient light. In this paper, we propose a new robust gamut mapping method which works against bright ambient light. The process is divided into two steps: lightness mapping (LM) and chroma reproduction. LM aligns the lightness level of sRGB gamut with OST gamut and partitions the region of OST gamut based on the relative size of the sRGB gamut and its lightness value. The second step (chroma reproduction) determines an appropriate chroma reproduction method (gamut compression or extension) and a proper direction for gamut mapping based on the characteristics of each region in order to minimize the effects of ambient light. The quality of color reproduction is qualitatively and quantitatively evaluated based on accurate measurements of the displayed colors. It has been experimentally confirmed that the proposed gamut mapping method can reduce color distortion more than the existing parametric gamut mapping algorithms.

17.
BMB Rep ; 53(6): 317-322, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32317079

RESUMO

Non-alcoholic fatty liver disease (NAFLD) is one of the most common liver diseases. NAFLD can further progress to irreversible liver failure such as non-alcoholic steatohepatitis (NASH) fibrosis and cirrhosis. However, specific regulator of NASH fibrosis has yet to be established. Here, we found that glutathione peroxidase 7 (GPx7) was markedly expressed in NASH fibrosis. Although GPx7 is an antioxidant enzyme protecting other organs, whether GPx7 plays a role in NASH fibrosis has yet to be studied. We found that knockdown of GPx7 in transforming growth factor-ß (TGF-ß) and free fatty acids (FFA)-treated LX-2 cells elevated the expression of pro-fibrotic and pro-inflammatory genes and collagen synthesis. Consistently, GPx7 overexpression in LX-2 cells led to the suppression of ROS production and reduced the expression of pro-fibrotic and pro-inflammatory genes. Further, NASH fibrosis induced by choline-deficient amino acid defined, high fat diet (CDAHFD) feeding was significantly accelerated by knockdown of GPx7, as evidenced by up-regulated liver fibrosis and inflammation compared with CDAHFD control mice. Collectively, these results suggest that GPx7 might be a novel therapeutic target to prevent the progression and development of NAFLD. [BMB Reports 2020; 53(6): 317-322].


Assuntos
Proteínas de Transporte/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Estresse Oxidativo , Animais , Células Cultivadas , Modelos Animais de Doenças , Masculino , Camundongos , Camundongos Endogâmicos C57BL
18.
Mar Environ Res ; 157: 104959, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32275500

RESUMO

The desiccation tolerance of the intertidal seagrass Zostera japonica has been demonstrated in a number of studies; however, the factors limiting expansion of intertidal seagrass species into subtidal zones remain controversial. We transplanted Z. japonica shoots from the intermediate intertidal zone into the plots with and without Z. marina shoots in both the lower intertidal and shallow subtidal zones to investigate the factors controlling Z. japonica growth in these zones. Daily photon flux density at the Z. japonica canopy level was attenuated by both water depth and coexisting Z. marina shoots but more strongly by Z. marina shoots than water depth in the transplant plots. The shoot density and biomass of Z. japonica transplants were significantly lower in transplant plots in the subtidal zone than in the lower intertidal zone. Although the photon flux density was significantly lower in transplant plots containing Z. marina shoots, the growth of Z. japonica transplants did not differ significantly between plots with and those without Z. marina shoots. Z. japonica transplants exhibited photoacclimatory responses such as increased shoot height and chlorophyll content under the lower-light conditions, offsetting the reduced light availability so that no significant differences in transplant growth occurred between plots with and those without Z. marina shoots. As the growth of Z. japonica transplants decreased significantly in the subtidal zone, the interactive effects of environmental stresses associated with tidal inundation and reduced light availability may restrict penetration of the intertidal seagrass Z. japonica into the subtidal zone. The persistence of high photosynthetic performance after air exposure and a regular arrangement of the densely overlapped leaves atop wet sediments may be desiccation tolerance mechanisms for Z. japonica in the intertidal zone.


Assuntos
Biomassa , Fotossíntese , Zosteraceae/crescimento & desenvolvimento , Oceano Pacífico , Folhas de Planta , Estresse Fisiológico
19.
Korean J Ophthalmol ; 34(2): 97-105, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32233142

RESUMO

PURPOSE: To investigate the pathway and effects of minoxidil on trabecular outflow in cultured human trabecular meshwork (TM) cells. METHODS: After exposing primarily cultured TM cells to 0, 10, 50, or 100 µM minoxidil sulfate (MS), trabecular outflow was assessed by measuring TM cell monolayer permeability to carboxyfluorescein and transepithelial electrical resistance. To assess the pathway of permeability changes, caveolin-1, occludin, and claudin-5 levels were measured via western blot. Generation of reactive oxygen species (ROS) was measured using the dichlorofluorescein diacetate assay. To assess the involvement of nitric oxide (NO) in minoxidil-induced permeability increase, the degrees of endothelial nitric oxide synthase mRNA expression and NO production were measured with reverse transcription polymerase chain reaction and Griess assays, respectively. Permeability was also measured with co-exposure to 50 µM N-acetyl cysteine. RESULTS: MS significantly increased TM cell monolayer permeability (p < 0.05) and decreased transepithelial electrical resistance (p < 0.05). MS decreased the degree of endothelial nitric oxide synthase mRNA expression but did not affect NO production. MS decreased occludin and claudin-5 levels but did not affect caveolin-1 level. MS at 100 µM increased the generation of ROS, and MS-induced permeability increase was attenuated after co-exposure to 50 µM N-acetyl cysteine. CONCLUSIONS: Minoxidil may preferentially increase trabecular permeability via a paracellular pathway by downregulation of tight junction proteins. This minoxidil-induced permeability through the TM may be mediated by generation of ROS.


Assuntos
Minoxidil/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Malha Trabecular/efeitos dos fármacos , Western Blotting , Células Cultivadas , Humanos , Óxido Nítrico/metabolismo , Permeabilidade/efeitos dos fármacos , Malha Trabecular/citologia , Malha Trabecular/metabolismo , Vasodilatadores/farmacologia
20.
Metabolism ; 108: 154250, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32335074

RESUMO

BACKGROUND: Chronic steroid treatment causes an increase in visceral adiposity and osteoporosis. It is believed that steroids may alter a balance between differentiation of mesenchymal stem cells (MSCs) into either adipocytes or osteoblasts; however, the detailed molecular mechanisms are unclear. We previously identified Dexras1 as a critical factor that potentiates adipogenesis in response to glucocorticoids. Thus, in this study, we investigated the role of Dexras1 in maintaining the balance between chronic steroid treatment-associated adipogenesis and osteoporosis. MATERIAL AND METHODS: We treated wild type (WT) and Dexras1 knockout (KO) mice with dexamethasone for five weeks followed by 60% HFD for additional two weeks with dexamethasone. The changes of glucocorticoid-induced body weight gain and osteoporosis were analyzed. Bone marrow derived stromal cells (BMSCs) and mouse embryonic fibroblasts (MEFs) extracted from WT and Dexras1 KO mice, as well as MC3T3-E1 pre-osteoblasts and osteoclasts differentiated from RAW264.7 were analyzed to further define the role of Dexras1 in osteoblasts and osteoclasts. RESULTS: Dual-energy X-ray absorptiometry and micro-computed tomography analyses in murine femurs revealed that Dexras1 deficiency was associated with increased osteogenesis, concurrent with reduced adipogenesis. Furthermore, Dexras1 deficiency promoted osteogenesis of BMSCs and MEFs in vitro, suggesting that Dexras1 deficiency prevents steroid-induced osteoporosis. We also observed that Dexras1 downregulated SMAD signaling pathways, which reduced the osteogenic differentiation capacity of pre-osteoblast MC3T3-E1 cells into mature osteoblasts. CONCLUSION: We propose that Dexras1 is critical for maintaining the equilibrium between adipogenesis and osteogenesis upon steroid treatment.


Assuntos
Adipogenia/fisiologia , Osteogênese/fisiologia , Proteínas ras/metabolismo , Células 3T3 , Adipócitos/metabolismo , Animais , Diferenciação Celular/fisiologia , Linhagem Celular , Fêmur/metabolismo , Glucocorticoides/metabolismo , Masculino , Células-Tronco Mesenquimais/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Osteoblastos/metabolismo , Osteoclastos/metabolismo , Osteoporose/metabolismo , Células RAW 264.7 , Transdução de Sinais/fisiologia
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