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1.
Front Microbiol ; 14: 944369, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36846745

RESUMO

Background: Previous studies have shown that patients with immunosuppression tend to have longer-lasting SARS-CoV-2 infections and a number of mutations were observed during the infection period. However, these studies were, in general, conducted longitudinally. Mutation evolution among groups of patients with immunosuppression have not been well studied, especially among Asian populations. Methods: Our study targeted a nosocomial cluster of SARS-CoV-2 infection in a Japanese medical center during Delta surge (AY.29 sublineage), involving ward nurses and inpatients. Whole-genome sequencing analyses were performed to examine mutation changes. Haplotype and minor variant analyses were furtherly performed to detect the mutations on the viral genomes in detail. In addition, sequences of the first wild-type strain hCoV-19/Wuhan/WIV04/2019 and AY.29 wild-type strain hCoV-19/Japan/TKYK15779/2021 were used as references to assess the phylogenetical development of this cluster. Results: A total of 6 nurses and 14 inpatients were identified as a nosocomial cluster from September 14 through 28, 2021. All were Delta variant (AY.29 sublineage) positive. 92.9% of infected patients (13 out of 14) were either cancer patients and/or receiving immunosuppressive or steroid treatments. Compared to AY.29 wild type, a total of 12 mutations were found in the 20 cases. Haplotype analysis found one index group of eight cases with F274F (N) mutation and 10 other haplotypes with one to three additional mutations. Furthermore, we found that cases with more than three minor variants were all cancer patients under immunosuppressive treatments. The phylogenetical tree analysis, including 20 nosocomial cluster-associated viral genomes, the first wild-type strain and the AY.29 wild-type strain as references, indicated the mutation development of the AY.29 virus in this cluster. Conclusion: Our study of a nosocomial SARS-CoV-2 cluster highlights mutation acquisition during transmission. More importantly, it provided new evidence emphasizing the need to further improve infection control measures to prevent nosocomial infection among immunosuppressed patients.

2.
Artif Life Robot ; 28(2): 471-482, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36644713

RESUMO

This paper presents a point-cloud mapping method using a light detection and ranging (LiDAR) mounted on a helmet worn by a rider of micro-mobility. The distortion in LiDAR measurements, which is caused by motion and shaking of micro-mobility and rider, is corrected by estimating the pose (3D positions and attitude angles) of the helmet based on the information from normal distributions transform-based simultaneous localization and mapping (NDT SLAM) and an inertial measurement unit. A Kalman filter-based algorithm for the distortion correction is presented under the assumption that the helmet moves at nearly constant translational and angular velocities in any directions. The distortion-corrected LiDAR measurements are mapped onto an elevation map, and the measurements relating to stationary objects in the environments are extracted using the occupancy grid method. The stationary object measurements are utilized to build a point-cloud map. The experimental results in a campus road environment demonstrate the effectiveness of the proposed method.

3.
J Emerg Med ; 60(3): e39-e44, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33353810

RESUMO

BACKGROUND: Pseudomembranous tracheobronchitis (PMTB) is a rare condition characterized by the formation of endobronchial pseudomembranes. PMTB overlaps with necrotizing tracheobronchitis or plastic bronchitis. The reported infectious etiology mainly includes invasive aspergillosis. PMTB can cause serious airway obstruction; however, urgent tracheotomy is rarely required. CASE REPORT: A 46-year-old woman was transferred to the emergency department (ED) with a 1-week history of progressive dyspnea and cough that was preceded by fever and sore throat. She was previously healthy except for a 20-year history of mild palmoplantar pustulosis. Stridor was evident. Nasolaryngoscopy performed in the ED revealed severe tracheal stenosis caused primarily by mucosal edema and secondarily by pseudomembranes. Initially, tracheitis was considered the sole cause of dyspnea. Although she underwent urgent tracheotomy to prevent asphyxia, her respiration deteriorated progressively. Bronchoscopy revealed massive pseudomembranes obstructing the bilateral bronchi, which led to the clinical diagnosis of PMTB. Subsequent toilet bronchoscopy markedly improved her ventilation. The causative pathogen was not identified despite extensive work-up, including molecular biological testing. Histopathologic examination of the pseudomembranes revealed fibrin with abundant neutrophils, which was consistent with PMTB. Associated conditions, including immunodeficiency, were not found. Her condition improved with antibiotics and repeated toilet bronchoscopy. WHY SHOULD AN EMERGENCY PHYSICIANS BE AWARE OF THIS?: PMTB is an important differential diagnosis of airway emergencies. PMTB can present with critical edematous tracheal stenosis and masked bronchial pseudomembranous obstruction. Emergency physicians should include PMTB in the differential diagnosis in adult patients with acute central airway obstruction because it requires prompt multimodal treatment.


Assuntos
Obstrução das Vias Respiratórias , Aspergilose , Bronquite , Estenose Traqueal , Traqueíte , Adulto , Obstrução das Vias Respiratórias/etiologia , Bronquite/complicações , Bronquite/diagnóstico , Broncoscopia , Feminino , Humanos , Pessoa de Meia-Idade , Estenose Traqueal/complicações , Estenose Traqueal/diagnóstico , Traqueíte/complicações , Traqueíte/diagnóstico
5.
Opt Express ; 26(19): 24864-24880, 2018 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-30469597

RESUMO

We propose off-axis virtual-image display and camera systems, which integrate a vertically-standing holographic off-axis mirror, blur-compensation optical systems, and digital imaging devices. In the system, the holographic mirror is used for an off-axis reflector, which realizes an upright and thin screen for virtual-image formation. By combining it with a display unit, an off-axis virtual-image display is realized, where the virtual image can be seen behind the upright holographic mirror. Simultaneously, by combining it with a camera unit, an off-axis camera is implemented, which realizes frontal shooting of objects by a camera placed at an off-axis position. Since both the off-axis display and the camera can be implemented by a single holographic mirror, it can be applied to a two-way visual-telecommunication system with a thin screen, which implements eye contact and the observer--image distance. A problem with the proposed system is image blur, which is caused by the chromatic dispersion of the holographic mirror. To solve this, we designed optical blur-compensation systems using a diffractive optical element and a diffuser or a lens. Experimental results verify the concept of the proposed systems with clarifying the effect of designed blur-compensation methods.

7.
J Clin Lab Anal ; 30(2): 114-22, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25545464

RESUMO

BACKGROUND: Selenoprotein P (SeP), a selenium-rich extracellular glycoprotein, is the primary selenoprotein in the plasma. SeP plays an important role in the maintenance of selenium levels in the peripheral tissues. We developed a new sol particle homogeneous immunoassay (SPIA) for measuring full-length SeP (FL-SeP) levels in the human serum. METHODS: We used colloidal gold particles coated with two types of anti-SeP monoclonal antibodies, one recognizing the N-terminal side domain of SeP and the other recognizing the C-terminal side domain. RESULTS: The assay range was 0.2-9 mg/l, and the linearity was excellent. The within-day and between-day coefficients of variation ranged from 0.73% to 2.24% and 0.45% to 1.11%, respectively. Serum samples (n = 200) were examined using the newly developed assay system (employing a Model 7070 Hitachi automatic clinical analyzer) and the conventional enzyme-linked immunosorbent assay. These two methods were compared using the Passing-Bablok regression analysis; the resulting regression equation and correlation coefficient were y = 0.940x + 0.165 and r = 0.954, respectively. CONCLUSIONS: Our new SPIA assay is a fully automated homogeneous immunoassay that can be used in conjunction with various commercial analyzers. The assay was sensitive, precise, and suitable for clinical measurement of the FL-SeP in the human serum.


Assuntos
Imunoensaio/métodos , Selenoproteína P/sangue , Anticoagulantes/farmacologia , Calibragem , Ensaio de Imunoadsorção Enzimática , Coloide de Ouro , Hemaglutinação , Humanos , Calicreínas/sangue , Limite de Detecção , Proteólise
8.
Appl Microbiol Biotechnol ; 100(2): 729-42, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26463999

RESUMO

Ammonia is a precursor to trichloramine, which causes an undesirable chlorinous odor. Granular activated carbon (GAC) filtration is used to biologically oxidize ammonia during drinking water purification; however, little information is available regarding the abundance and diversity of ammonia-oxidizing archaea (AOA) and bacteria (AOB) associated with GAC. In addition, their sources and fates in water purification process remain unknown. In this study, six GAC samples were collected from five full-scale drinking water purification plants in Tokyo during summer and winter, and the abundance and community structure of AOA and AOB associated with GAC were studied in these two seasons. In summer, archaeal and bacterial amoA genes on GACs were present at 3.7 × 10(5)-3.9 × 10(8) gene copies/g-dry and 4.5 × 10(6)-4.2 × 10(8) gene copies/g-dry, respectively. In winter, archaeal amoA genes remained at the same level, while bacterial amoA genes decreased significantly for all GACs. No differences were observed in the community diversity of AOA and AOB from summer to winter. Phylogenetic analysis revealed high AOA diversity in group I.1a and group I.1b in raw water. Terminal-restriction fragment length polymorphism analysis of processed water samples revealed that AOA diversity decreased dramatically to only two OTUs in group I.1a after ozonation, which were identical to those detected on GAC. It suggests that ozonation plays an important role in determining AOA diversity on GAC. Further study on the cell-specific activity of AOA and AOB is necessary to understand their contributions to in situ nitrification performance.


Assuntos
Amônia/metabolismo , Archaea/genética , Archaea/metabolismo , Bactérias/genética , Bactérias/metabolismo , Água Potável/microbiologia , Archaea/classificação , Archaea/isolamento & purificação , Bactérias/classificação , Bactérias/isolamento & purificação , Carvão Vegetal , Água Potável/análise , Variação Genética , Consórcios Microbianos/genética , Consórcios Microbianos/fisiologia , Nitrificação , Oxirredução , Filogenia , Estações do Ano , Tóquio , Purificação da Água
9.
J Lipid Res ; 56(11): 2172-82, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26411970

RESUMO

Selenocysteine (Sec) insertion sequence-binding protein 2 (SBP2) is essential for the biosynthesis of Sec-containing proteins, termed selenoproteins. Subjects with mutations in the SBP2 gene have decreased levels of several selenoproteins, resulting in a complex phenotype. Selenoproteins play a significant role in antioxidative defense, and deficiencies in these proteins can lead to increased oxidative stress. However, lipid peroxidation and the effects of antioxidants in subjects with SBP2 gene mutations have not been studied. In the present study, we evaluated the lipid peroxidation products in the blood of a subject (the proband) with mutations in the SBP2 gene. We found that the proband had higher levels of free radical-mediated lipid peroxidation products, such as 7ß-hydroxycholesterol, than the control subjects. Treatment of the proband with vitamin E (α-tocopherol acetate, 100 mg/day), a lipid-soluble antioxidant, for 2 years reduced lipid peroxidation product levels to those of control subjects. Withdrawal of vitamin E treatment for 7 months resulted in an increase in lipid peroxidation products. Collectively, these results clearly indicate that free radical-mediated oxidative stress is increased in the subject with SBP2 gene mutations and that vitamin E treatment effectively inhibits the generation of lipid peroxidation products.


Assuntos
Antioxidantes/uso terapêutico , Peroxidação de Lipídeos/efeitos dos fármacos , Proteínas de Ligação a RNA/genética , Vitamina E/uso terapêutico , Adolescente , Antioxidantes/farmacologia , Estudos de Casos e Controles , Criança , Feminino , Humanos , Contagem de Leucócitos , Masculino , Doenças Metabólicas/tratamento farmacológico , Mutação de Sentido Incorreto , Selenoproteínas/sangue , Vitamina E/farmacologia
10.
J Med Chem ; 58(17): 7088-92, 2015 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-26305288

RESUMO

We synthesized new vitamin K2 analogues with ω-terminal modifications of the side chain and evaluated their selective differentiation of neuronal progenitor cells into neurons in vitro. The result of the assay showed that the menaquinone-3 analogue modified with the m-methylphenyl group had the most potent activity, which was twice as great as the control. This finding indicated that it is possible to obtain much more potent compounds with modification of the structure of vitamin K2.


Assuntos
Células-Tronco Multipotentes/efeitos dos fármacos , Células-Tronco Neurais/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Vitamina K 2/análogos & derivados , Vitamina K 2/química , Animais , Diferenciação Celular , Camundongos , Células-Tronco Multipotentes/citologia , Neocórtex/citologia , Células-Tronco Neurais/citologia , Neurônios/citologia , Estereoisomerismo , Relação Estrutura-Atividade , Vitamina K 2/farmacologia
11.
J Amino Acids ; 2014: 434056, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25254114

RESUMO

Thin layers of pyroglutamic acid (Pygl) have been deposited by thermal evaporation of the molten L-glutamic acid (L-Glu) through intramolecular lactamization. This deposition was carried out with the versatile handmade low-vacuum coater, which was simply composed of a soldering iron placed in a vacuum degassing resin chamber evacuated by an oil-free diaphragm pump. Molecular structural analyses have revealed that thin solid film evaporated from the molten L-Glu is mainly composed of L-Pygl due to intramolecular lactamization. The major component of the L-Pygl was in ß-phase and the minor component was in γ-phase, which would have been generated from partial racemization to DL-Pygl. Electron microscopy revealed that the L-Glu-evaporated film generally consisted of the 20 nm particulates of Pygl, which contained a periodic pattern spacing of 0.2 nm intervals indicating the formation of the single-molecular interval of the crystallized molecular networks. The DL-Pygl-evaporated film was composed of the original DL-Pygl preserving its crystal structures. This methodology is promising for depositing a wide range of the evaporable organic materials beyond amino acids. The quartz crystal resonator coated with the L-Glu-evaporated film exhibited the pressure-sensing capability based on the adsorption-desorption of the surrounding gas at the film surface.

12.
Diabetologia ; 57(9): 1968-76, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24989996

RESUMO

AIMS/HYPOTHESIS: Impaired angiogenesis induced by vascular endothelial growth factor (VEGF) resistance is a hallmark of vascular complications in type 2 diabetes; however, its molecular mechanism is not fully understood. We have previously identified selenoprotein P (SeP, encoded by the SEPP1 gene in humans) as a liver-derived secretory protein that induces insulin resistance. Levels of serum SeP and hepatic expression of SEPP1 are elevated in type 2 diabetes. Here, we investigated the effects of SeP on VEGF signalling and angiogenesis. METHODS: We assessed the action of glucose on Sepp1 expression in cultured hepatocytes. We examined the actions of SeP on VEGF signalling and VEGF-induced angiogenesis in HUVECs. We assessed wound healing in mice with hepatic SeP overexpression or SeP deletion. The blood flow recovery after ischaemia was also examined by using hindlimb ischaemia model with Sepp1-heterozygous-knockout mice. RESULTS: Treatment with glucose increased gene expression and transcriptional activity for Sepp1 in H4IIEC hepatocytes. Physiological concentrations of SeP inhibited VEGF-stimulated cell proliferation, tubule formation and migration in HUVECs. SeP suppressed VEGF-induced reactive oxygen species (ROS) generation and phosphorylation of VEGF receptor 2 (VEGFR2) and extracellular signal-regulated kinase 1/2 (ERK1/2) in HUVECs. Wound closure was impaired in the mice overexpressing Sepp1, whereas it was improved in SeP (-/-)mice. SeP (+/-)mice showed an increase in blood flow recovery and vascular endothelial cells after hindlimb ischaemia. CONCLUSIONS/INTERPRETATION: The hepatokine SeP may be a novel therapeutic target for impaired angiogenesis in type 2 diabetes.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Células Endoteliais/metabolismo , Selenoproteína P/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Proliferação de Células/genética , Proliferação de Células/fisiologia , Diabetes Mellitus Tipo 2/genética , Glucose/metabolismo , Hepatócitos/metabolismo , Células Endoteliais da Veia Umbilical Humana , Camundongos , Camundongos Knockout , Camundongos Mutantes , Regiões Promotoras Genéticas/genética , Selenoproteína P/genética , Fator A de Crescimento do Endotélio Vascular/genética , Cicatrização/genética , Cicatrização/fisiologia
13.
J Trace Elem Med Biol ; 27(1): 40-4, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22766353

RESUMO

OBJECTIVES: Selenoprotein P (SeP) is a selenium (Se) supply protein, which is an antioxidant micronutrient considered to be vital for human health. The aim of this study was to assess the serum selenium status in patients with silicosis. METHODS: We conducted a retrospective case-control study where serum samples from a total of 78 patients (males with a median age of 73.5 years old) with silicosis and 20 healthy controls (males with a median age of 72.5 years old) were assayed for Se and SeP. They underwent medical and job history taking, lung function testing, and chest radiography examinations. Levels of serum Se were measured using electrothermal atomic absorption spectrophotomerty, while levels of SeP were assessed with sandwich Enzyme Immunoassay. Spearman's rank correlation test was carried out to evaluate the relationship between Se and SeP. The Mann-Whitney test was used to evaluate differences in serum Se and SeP between study groups. RESULTS: The median serum Se and SeP concentrations were significantly lower in cases (74.0 µg/l and 4.2mg/l, respectively) compared with controls (116.0 µg/l and 5.8 mg/l, respectively). In both cases and controls, serum Se was positively correlated with serum SeP (rho=0.781, p<0.001 and rho=0.768, p<0.001, respectively). Serum Se and SeP levels were significantly lower in patients classified in category four compared with those who were classified in category two or three. CONCLUSIONS: Serum Se and SeP concentrations were found to be at inadequate levels in patients with silicosis, and decreased significantly with the severity of the disease.


Assuntos
Selênio/sangue , Selenoproteína P/sangue , Silicose/sangue , Idoso , Idoso de 80 Anos ou mais , Humanos , Masculino , Pessoa de Meia-Idade
14.
Sensors (Basel) ; 12(11): 14489-507, 2012 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-23202171

RESUMO

This paper presents an outdoors laser-based pedestrian tracking system using a group of mobile robots located near each other. Each robot detects pedestrians from its own laser scan image using an occupancy-grid-based method, and the robot tracks the detected pedestrians via Kalman filtering and global-nearest-neighbor (GNN)-based data association. The tracking data is broadcast to multiple robots through intercommunication and is combined using the covariance intersection (CI) method. For pedestrian tracking, each robot identifies its own posture using real-time-kinematic GPS (RTK-GPS) and laser scan matching. Using our cooperative tracking method, all the robots share the tracking data with each other; hence, individual robots can always recognize pedestrians that are invisible to any other robot. The simulation and experimental results show that cooperating tracking provides the tracking performance better than conventional individual tracking does. Our tracking system functions in a decentralized manner without any central server, and therefore, this provides a degree of scalability and robustness that cannot be achieved by conventional centralized architectures.


Assuntos
Lasers , Robótica , Caminhada , Humanos , Modelos Teóricos
15.
PLoS One ; 7(4): e34952, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22496878

RESUMO

BACKGROUND: We recently identified selenoprotein P (SeP) as a liver-derived secretory protein that causes insulin resistance in the liver and skeletal muscle; however, it is unknown whether and, if so, how SeP acts on adipose tissue. The present study tested the hypothesis that SeP is related to hypoadiponectinemia in patients with type 2 diabetes. METHODOLOGY/PRINCIPAL FINDINGS: We compared serum levels of SeP with those of adiponectin and other clinical parameters in 36 patients with type 2 diabetes. We also measured levels of blood adiponectin in SeP knockout mice. Circulating SeP levels were positively correlated with fasting plasma glucose (r = 0.35, P = 0.037) and negatively associated with both total and high-molecular adiponectin in patients with type 2 diabetes (r = -0.355, P = 0.034; r = -0.367, P = 0.028). SeP was a predictor of both total and high-molecular adiponectin, independently of age, body weight, and quantitative insulin sensitivity index (ß = -0.343, P = 0.022; ß = -0.357, P = 0.017). SeP knockout mice exhibited an increase in blood adiponectin levels when fed regular chow or a high sucrose, high fat diet. CONCLUSIONS/SIGNIFICANCE: These results suggest that overproduction of liver-derived secretory protein SeP is connected with hypoadiponectinemia in patients with type 2 diabetes.


Assuntos
Adiponectina/sangue , Selenoproteína P/sangue , Idoso , Animais , Glicemia/análise , Diabetes Mellitus Tipo 2/sangue , Dieta Hiperlipídica , Sacarose Alimentar/metabolismo , Jejum/metabolismo , Feminino , Humanos , Insulina/sangue , Resistência à Insulina/fisiologia , Masculino , Camundongos , Camundongos Knockout , Pessoa de Meia-Idade , Selenoproteína P/genética
16.
J Med Chem ; 55(4): 1553-8, 2012 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-22250752

RESUMO

We synthesized new vitamin K analogues with demethylation or reduction of the double bonds of the side chain of menaquinone-4 (MK-4) and evaluated their SXR-mediated transcriptional activity as well as the extent of their conversion to MK-4. The results indicated that the analogue with the methyl group deleted at the 7' site of the side chain part affected conversion activity to MK-4. In contrast, a decrease in the number of the double bonds in the side chain moiety appeared to decrease the SXR-mediated transcriptional activity.


Assuntos
Receptores de Esteroides/metabolismo , Transcrição Gênica/efeitos dos fármacos , Vitamina K 2/análogos & derivados , Linhagem Celular Tumoral , Deutério , Genes Reporter , Humanos , Luciferases/biossíntese , Luciferases/genética , Receptor de Pregnano X , Ligação Proteica , Multimerização Proteica , Receptores de Esteroides/genética , Receptores X de Retinoides/metabolismo , Relação Estrutura-Atividade , Vitamina K 2/síntese química , Vitamina K 2/química , Vitamina K 2/farmacologia
17.
J Med Chem ; 54(12): 4269-73, 2011 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-21561094

RESUMO

Vitamin K(2) is a ligand for a nuclear receptor, steroid and xenobiotic receptor (SXR), that induces the gene expressions of CYP3A4. We synthesized vitamin K(2) analogues with hydroxyl or phenyl groups at the ω-terminal of the side chain. The up-regulation of SXR-mediated transcription of the target gene by the analogues was dependent on the length of the side chain and the hydrophobicity of the ω-terminal residues. Phenyl analogue menaquinone-3 was as active as the known SXR ligand rifampicin.


Assuntos
Receptores de Esteroides/agonistas , Transcrição Gênica/efeitos dos fármacos , Vitamina K 2/análogos & derivados , Vitamina K 2/síntese química , Células Hep G2 , Humanos , Ligantes , Luciferases/biossíntese , Luciferases/genética , Modelos Moleculares , Receptor de Pregnano X , Relação Estrutura-Atividade , Vitamina K 2/farmacologia
18.
J Med Chem ; 54(13): 4918-22, 2011 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-21618996

RESUMO

Vitamin K(2) has been demonstrated to induce gene expression related to bone formation through a nuclear steroid and xenobiotic receptor (SXR). We synthesized new vitamin K analogues with the same isoprene side chains symmetrically introduced at the 2 and 3 positions of 1,4-naphthoquinone and evaluated the transcriptional activity of the target gene. The transcriptional activity was related to the length of the side chain which allowed optimal interaction with ligand-binding domain of SXR.


Assuntos
Receptores de Esteroides/agonistas , Vitamina K/análogos & derivados , Vitamina K/síntese química , Sítios de Ligação , Butadienos/síntese química , Butadienos/química , Butadienos/farmacologia , Genes Reporter , Hemiterpenos/síntese química , Hemiterpenos/química , Hemiterpenos/farmacologia , Células Hep G2 , Humanos , Ligantes , Luciferases/biossíntese , Luciferases/genética , Pentanos/síntese química , Pentanos/química , Pentanos/farmacologia , Receptor de Pregnano X , Receptores de Esteroides/genética , Relação Estrutura-Atividade , Transcrição Gênica/efeitos dos fármacos , Vitamina K/farmacologia
19.
Prostate ; 71(8): 824-34, 2011 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-21456065

RESUMO

BACKGROUND: Oxidative stress plays a role in prostate cancer (PrCa) initiation and development. Selenoprotein-P (SepP; a protein involved in antioxidant defence) mRNA levels are down-regulated in PrCa. The main goal of our study was to assess whether SepP protects prostate cells from reactive oxygen species (ROS) in prostate carcinogenesis. METHODS: Modification of SepP levels and ROS conditions in C3(1)/Tag-derived cell lines representing prostate epithelial neoplasia (PIN) lesions (Pr-111, with high SepP expression); and invasive tumors (Pr-14, with very low SepP expression). RESULTS: Both Pr-111 and Pr-14 cells express ApoER2 (SepP receptor), which suggests that they may uptake SepP. Pr-14 cells had much higher ROS levels than Pr-111 cells and were highly sensitive to H(2)O(2)-mediated cytotoxicity. When SepP mRNA levels were knocked down with siRNAs in Pr-111 cells, a significant increase in ROS and cell growth inhibition upon H(2)O(2) exposure was found. Subsequent administration of purified SepP in the culture medium of these cells was able to rescue the original phenotype. Similarly, administration of SepP to Pr-14 cells was able to reduce ROS concentrations. Administration of flutamide decreased SepP mRNA levels whereas dihydrotestosterone or synthetic androgens induced SepP expression, indicating the importance of androgens for SepP expression. Immunohistochemical analysis using a PrCa tissue microarray further revealed that SepP protein was reduced in 60.8% prostate tumors compared to benign prostates. CONCLUSIONS: Levels of SepP in prostate cells determine basal ROS levels and sensitivity to H(2)O(2)-induced cytotoxicity. Deregulation of SepP during prostate carcinogenesis may increase free radicals, thus promoting tumor development and de-differentiation.


Assuntos
Carcinoma/metabolismo , Estresse Oxidativo , Neoplasia Prostática Intraepitelial/metabolismo , Neoplasias da Próstata/metabolismo , Selenoproteína P/antagonistas & inibidores , Antagonistas de Androgênios/farmacologia , Carcinoma/patologia , Linhagem Celular Tumoral , Transformação Celular Neoplásica/metabolismo , Regulação para Baixo , Flutamida/farmacologia , Humanos , Peróxido de Hidrogênio/toxicidade , Masculino , Neoplasia Prostática Intraepitelial/patologia , Neoplasias da Próstata/patologia , RNA Interferente Pequeno/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Espécies Reativas de Oxigênio/toxicidade , Selenoproteína P/metabolismo
20.
Cell Metab ; 12(5): 483-95, 2010 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-21035759

RESUMO

The liver may regulate glucose homeostasis by modulating the sensitivity/resistance of peripheral tissues to insulin, by way of the production of secretory proteins, termed hepatokines. Here, we demonstrate that selenoprotein P (SeP), a liver-derived secretory protein, causes insulin resistance. Using serial analysis of gene expression (SAGE) and DNA chip methods, we found that hepatic SeP mRNA levels correlated with insulin resistance in humans. Administration of purified SeP impaired insulin signaling and dysregulated glucose metabolism in both hepatocytes and myocytes. Conversely, both genetic deletion and RNA interference-mediated knockdown of SeP improved systemic insulin sensitivity and glucose tolerance in mice. The metabolic actions of SeP were mediated, at least partly, by inactivation of adenosine monophosphate-activated protein kinase (AMPK). In summary, these results demonstrate a role of SeP in the regulation of glucose metabolism and insulin sensitivity and suggest that SeP may be a therapeutic target for type 2 diabetes.


Assuntos
Resistência à Insulina , Fígado/metabolismo , Selenoproteína P/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Linhagem Celular , Diabetes Mellitus Tipo 2/metabolismo , Feminino , Deleção de Genes , Regulação da Expressão Gênica , Glucose/metabolismo , Hepatócitos/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Ácido Palmítico/metabolismo , Fosforilação , Interferência de RNA , RNA Mensageiro/genética , Ratos , Selenoproteína P/genética
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