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1.
Transl Clin Pharmacol ; 31(1): 59-68, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37034122

RESUMO

Concomitant administration of lobeglitazone, empagliflozin, and metformin is expected to enhance blood glucose-lowering effects and improve medication compliance in patients with diabetes mellitus. In this study, we investigated the pharmacokinetic (PK) interactions and safety of lobeglitazone and co-administered empagliflozin and metformin, which are approved agents used in clinical settings. Two randomized, open-label, multiple-dose, 2-treatment, 2-period, 2-sequence crossover clinical trials (parts 1 and 2) were conducted independently. In part 1, lobeglitazone monotherapy or lobeglitazone, empagliflozin, and metformin triple therapy was administered for 5 days. In part 2, empagliflozin and metformin dual therapy or the abovementioned triple therapy were administered for 5 days. Serial blood samples were collected up to 24 hours after the last dose in each period for PK evaluation. The primary PK parameters (AUCtau,ss, Cmax,ss) of treatment regimens in each study part were calculated and compared. For lobeglitazone, the geometric mean ratios (GMRs) with 90% confidence intervals (CI) for triple therapy over monotherapy were 1.08 (1.03-1.14) for Cmax,ss and 0.98 (0.90-1.07) for AUCtau,ss. For empagliflozin, the GMRs and 90% CIs for triple therapy over dual therapy were 0.87 (0.78-0.97) for Cmax,ss and 0.97 (0.93-1.00) for AUCtau,ss. For metformin, the GMRs and 90% CIs for triple therapy over dual therapy were 1.06 (0.95-1.17) for Cmax,ss and 1.04 (0.97-1.12) for AUCtau,ss. All reported adverse events were mild. The triple therapy consisting of lobeglitazone, empagliflozin, and metformin did not show any clinically relevant drug interactions in relation to the PKs and safety of each drug substance. Trial Registration: ClinicalTrials.gov Identifier: NCT04334213.

2.
Circ Res ; 129(12): e215-e233, 2021 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-34702049

RESUMO

RATIONALE: Vascular smooth muscle cells (SMCs) exhibit remarkable plasticity and can undergo dedifferentiation upon pathological stimuli associated with disease and interventions. OBJECTIVE: Although epigenetic changes are critical in SMC phenotype switching, a fundamental regulator that governs the epigenetic machineries regulating the fate of SMC phenotype has not been elucidated. METHODS AND RESULTS: Using SMCs, mouse models, and human atherosclerosis specimens, we found that FAK (focal adhesion kinase) activation elicits SMC dedifferentiation by stabilizing DNMT3A (DNA methyltransferase 3A). FAK in SMCs is activated in the cytoplasm upon serum stimulation in vitro or vessel injury and active FAK prevents DNMT3A from nuclear FAK-mediated degradation. However, pharmacological or genetic FAK catalytic inhibition forced FAK nuclear localization, which reduced DNMT3A protein via enhanced ubiquitination and proteasomal degradation. Reduced DNMT3A protein led to DNA hypomethylation in contractile gene promoters, which increased SMC contractile protein expression. RNA-sequencing identified SMC contractile genes as a foremost upregulated group by FAK inhibition from injured femoral artery samples compared with vehicle group. DNMT3A knockdown in injured arteries reduced DNA methylation and enhanced contractile gene expression supports the notion that nuclear FAK-mediated DNMT3A degradation via E3 ligase TRAF6 (TNF [tumor necrosis factor] receptor-associated factor 6) drives differentiation of SMCs. Furthermore, we observed that SMCs of human atherosclerotic lesions exhibited decreased nuclear FAK, which was associated with increased DNMT3A levels and decreased contractile gene expression. CONCLUSIONS: This study reveals that nuclear FAK induced by FAK catalytic inhibition specifically suppresses DNMT3A expression in injured vessels resulting in maintaining SMC differentiation by promoting the contractile gene expression. Thus, FAK inhibitors may provide a new treatment option to block SMC phenotypic switching during vascular remodeling and atherosclerosis.


Assuntos
Desdiferenciação Celular , Proteínas Contráteis/genética , Metilação de DNA , Quinase 1 de Adesão Focal/metabolismo , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Animais , Células Cultivadas , Proteínas Contráteis/metabolismo , DNA Metiltransferase 3A/genética , DNA Metiltransferase 3A/metabolismo , Quinase 1 de Adesão Focal/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Músculo Liso Vascular/citologia , Miócitos de Músculo Liso/citologia , Miócitos de Músculo Liso/fisiologia , Proteólise , Ubiquitinação , Regulação para Cima
3.
Transl Clin Pharmacol ; 29(3): 150-159, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34621707

RESUMO

YH4808 is a novel potassium-competitive acid blocker developed for gastric acid-related disorders. Previous studies indicate its potential to improve symptoms of gastric acid-related disorders. The current study was aimed to find the optimal regimen of YH4808 for night time pH control. This study was performed in two parts. Each was a randomized, open-label, active-controlled, multiple-doses, two-treatment, two-period crossover study conducted in 20 healthy Korean volunteers. Subjects were randomly assigned to one of the four groups. The three groups received different dosage regimens of YH4808 (100 mg twice a day, 200 mg once a day, or 200 mg twice a day), and the fourth group received esomeprazole 40 mg twice a day. The pharmacokinetic parameters demonstrated that the systemic exposure of YH4808 increased in a dose-proportional manner. The difference in the proportion of time above pH 4 over 24 h from the baseline was the greatest in the group receiving YH4808 200 mg twice a day. The values of the area under the effect curve at night time (12 A.M.-7 A.M.) were higher in all YH4808 groups than in the esomeprazole group. However, the differences among the YH4808 groups were not statistically significant (p > 0.05). YH4808 exhibited potential for better pH control during the night in comparison to esomeprazole. The optimal regimen for night time pH control among all the YH4808 regimens was 200 mg twice a day. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01761513.

4.
Anesth Pain Med (Seoul) ; 16(1): 103-107, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33461245

RESUMO

BACKGROUND: Despite significant technological advances in the implantable pulse generator (IPG), complications can still occur. We report a case that unexpected extrusion of the IPG of spinal cord stimulation (SCS) was promptly identified and successfully removed without any complications. CASE: After a car accident 4 years ago, a 55-year-old male who was diagnosed with complex local pain syndrome in his right leg. The SCS was inserted with 2 leads, with the IPG being implanted in the right lower abdomen region. Four years later, he developed extrusion of the IPG from his abdominal region. This unexpected extrusion may have been related to pressure necrosis caused by continued compression of pocket site where a belt was frequently tied. The IPG and the leads were successfully removed without infection occurring. CONCLUSIONS: To prevent unexpected extrusion of IPG, it is necessary to consider in advance whether the pocket site is pressed against the belt.

5.
Ann Palliat Med ; 10(4): 4906-4910, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33183021

RESUMO

Although esophagectomy is a standard treatment for esophageal cancer, anastomotic leak after esophagectomy is a relatively common complication and its incidence is 10-25% for cervical anastomosis. Endoscopic vacuum therapy (EVT) is a feasible primary treatment of esophageal perforations and leaks. Currently, there are no anesthesia guidelines for EVT, however, it is usually performed under general anesthesia with endotracheal intubation, especially for cervical EVT. Here, we report a successful EVT under monitored anesthesia care (MAC) without any complication, which doesn't need to intubate the patient. A 64-year-old male with upper esophageal cancer underwent an Ivor-Lewis operation with cervical anastomosis. Vacuum assisted closure (VAC) was performed for cervical leak under general anesthesia, but there was no further improvement. Although EVT was attempted under sedation with midazolam in an endoscopy room, the procedure was discontinued because of desaturation. Furthermore, the thoracic surgeon was concerned about the possibility of dyspnea and hypoxia even after the procedure. EVT was scheduled under MAC at the request of a thoracic surgeon and medical doctor, as EVT was expected to lead to patient discomfort and difficult airway. EVT was performed successfully with no respiratory depression or patient movement using target controlled infusion with 2% propofol and remifentanil. The patient was discharged on the 78th POD without any other complications. EVT for cervical leak after esophagectomy can be successfully performed with MAC, and understanding the general condition of the patient, cooperation with the patient and the surgeon, and providing continuous oxygen supply to the patient are necessary for a successful procedure under MAC.


Assuntos
Anestesia , Tratamento de Ferimentos com Pressão Negativa , Fístula Anastomótica , Endoscopia , Esofagectomia/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade
6.
Transl Clin Pharmacol ; 28(3): 136-146, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33062627

RESUMO

YH4808 is a novel selective potassium-competitive acid blocker demonstrated to be safe and to have inhibitory effects against gastric acid secretion in previous studies. A randomized, open-label, multiple-dose, 3-treatment, 1-period, parallel design study was conducted to compare the Helicobacter pylori eradication rates and acid suppression capacities of three regimens in 60 healthy subjects with H. pylori-positive, and the potential of YH4808 to replace proton-pump inhibitors (PPIs) in standard regimens for H. pylori eradication. Group 1 received YH4808, amoxicillin, and clarithromycin as a novel triple regimen, while Group 2 received YH4808 and amoxicillin only, and Group 3 received esomeprazole, amoxicillin, and clarithromycin, as the standard triple regimen. H. pylori eradication rates were 85.0% for Group 1, 25.0% for Group 2, and 83.3% for Group 3. Relative response rate between Group 1 and 3 was 1.02 (0.50-2.07; 95% CI, χ2 test p = 0.8881). Furthermore, the novel triple regimen, YH4808, amoxicillin, and clarithromycin, stably inhibited acid secretion and maintained a gastric pH greater than 4 or 5 for 24 hours, which was comparable to the pH range in the standard triple regimen. However, the onset times of the YH4808 regimens were earlier than that for the regimens using esomeprazole. There were no differences in the incidences or severity of adverse events among the three groups. Overall, the novel triple regimen was safe and well-tolerated. YH4808 could replace PPIs in standard triple regimens used for H. pylori eradication. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01921647.

7.
Int J Mol Sci ; 21(17)2020 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-32867320

RESUMO

This study was conducted to monitor the macrophage infiltration of atopic dermatitis (AD)-like skin lesions and to evaluate the effects of anti-AD therapeutic agents in immunocompetent mice via optical reporter-gene-based molecular imaging. The enhanced firefly luciferase (effluc)-expressing macrophage cell line (Raw264.7/effluc) was intravenously introduced into mice with 2,4-dinitrochlorobenzene (DNCB)-induced AD, followed by bioluminescent imaging (BLI). After in vivo imaging, AD-like skin lesions were excised, and ex vivo imaging and Western blotting were conducted to determine the presence of infused macrophages. Finally, the therapeutic effect of dexamethasone (DEX), an AD-modulating agent, was evaluated via macrophage tracking. In vivo imaging with BLI revealed the migration of the reporter macrophages to DNCB-induced AD-like skin lesions on day 1 post-transfer. The greatest recruitment was observed on day 3, and a decline in BLI signal was observed on day 14. Notably, in vivo BLI clearly showed the inhibition of the reporter macrophage infiltration of DNCB-induced AD-like skin lesions by DEX, which was consistent with the reduced AD symptoms observed in DEX-treated mice. We successfully visualized the macrophage migration to DNCB-induced AD-like skin lesions, proving the feasibility of macrophage imaging for evaluating AD-regulating drugs in living organisms.


Assuntos
Dermatite Atópica/metabolismo , Dexametasona/administração & dosagem , Dinitroclorobenzeno/efeitos adversos , Luciferases de Vaga-Lume/genética , Macrófagos/transplante , Administração Intravenosa , Animais , Linhagem Celular , Dermatite Atópica/induzido quimicamente , Dexametasona/farmacologia , Modelos Animais de Doenças , Feminino , Genes Reporter , Luciferases de Vaga-Lume/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Imagem Molecular , Imagem Óptica , Células RAW 264.7 , Resultado do Tratamento
8.
Transl Clin Pharmacol ; 28(1): 55-65, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32274381

RESUMO

YH4808 is a novel potassium-competitive acid blocker that was developed as a therapeutic agent for gastric acid-related diseases; it may replace proton pump inhibitors, which are widely used in combination with amoxicillin and clarithromycin for Helicobacter pylori eradication. We compared the pharmacokinetic (PK) profiles and safety of amoxicillin, clarithromycin, and YH4808 used as monotherapies or in combination for evaluating potential drug interactions. An open-label, randomized, single-dose, Latin-square (4 × 4) crossover study was conducted in 32 healthy Korean volunteers. Subjects were randomly assigned to one of the 4 treatment sequences that consisted of 4 periods separated by 21-day washout intervals. PK parameters of YH4808, amoxicillin and clarithromycin administered in combination were compared with those of the respective monotherapies. The geometric mean ratios of the maximum concentration (Cmax) and the area under the time-concentration curve from time zero to time of the last quantifiable concentration (AUClast) of YH4808 increased during the triple therapy by 48.6% and 29.1%, respectively. Similarly, the Cmax and AUClast of M3 (active metabolite of YH4808) increased by 23.3% and 16.0%, respectively. The Cmax and AUClast of clarithromycin increased by 27.4% and 30.5%, and those of 14-hydroxyclarithromycin were increased by 23.1% and 32.4%, respectively. The corresponding amoxicillin values decreased during the triple therapy by 21.5% and 15.6%, respectively. There was no clinically significant change in safety assessment related to either monotherapies or triple therapy. In conclusion, amoxicillin, clarithromycin and YH4808 administered as triple therapy did not exhibit significant PK interactions and were not associated with safety issues. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01921647.

9.
Circ Res ; 125(2): 152-166, 2019 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-31096851

RESUMO

RATIONALE: Neointimal hyperplasia is characterized by excessive accumulation of vascular smooth muscle cells (SMCs) leading to occlusive disorders, such as atherosclerosis and stenosis. Blood vessel injury increases growth factor secretion and matrix synthesis, which promotes SMC proliferation and neointimal hyperplasia via FAK (focal adhesion kinase). OBJECTIVE: To understand the mechanism of FAK action in SMC proliferation and neointimal hyperplasia. METHODS AND RESULTS: Using combined pharmacological FAK catalytic inhibition (VS-4718) and SMC-specific FAK kinase-dead (Myh11-Cre-ERT2) mouse models, we report that FAK regulates SMC proliferation and neointimal hyperplasia in part by governing GATA4- (GATA-binding protein 4) cyclin D1 signaling. Inhibition of FAK catalytic activity facilitates FAK nuclear localization, which is required for proteasome-mediated GATA4 degradation in the cytoplasm. Chromatin immunoprecipitation identified GATA4 binding to the mouse cyclin D1 promoter, and loss of GATA4-mediated cyclin D1 transcription diminished SMC proliferation. Stimulation with platelet-derived growth factor or serum activated FAK and redistributed FAK from the nucleus to cytoplasm, leading to concomitant increase in GATA4 protein and cyclin D1 expression. In a femoral artery wire injury model, increased neointimal hyperplasia was observed in parallel with elevated FAK activity, GATA4 and cyclin D1 expression following injury in control mice, but not in VS-4718-treated and SMC-specific FAK kinase-dead mice. Finally, lentiviral shGATA4 knockdown in the wire injury significantly reduced cyclin D1 expression, SMC proliferation, and neointimal hyperplasia compared with control mice. CONCLUSIONS: Nuclear enrichment of FAK by inhibition of FAK catalytic activity during vessel injury blocks SMC proliferation and neointimal hyperplasia through regulation of GATA4-mediated cyclin D1 transcription.


Assuntos
Proliferação de Células , Ciclina D1/metabolismo , Quinase 1 de Adesão Focal/metabolismo , Fator de Transcrição GATA4/metabolismo , Miócitos de Músculo Liso/metabolismo , Túnica Íntima/metabolismo , Transporte Ativo do Núcleo Celular , Animais , Núcleo Celular/metabolismo , Células Cultivadas , Ciclina D1/genética , Quinase 1 de Adesão Focal/antagonistas & inibidores , Hiperplasia/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Miócitos de Músculo Liso/fisiologia , Túnica Íntima/patologia
10.
Exp Mol Med ; 51(4): 1-9, 2019 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-30988419

RESUMO

Estrogen receptor alpha (ERα) is a sex hormone nuclear receptor that regulates various physiological events, including the immune response. Although there have been some recent studies on ERα regarding subsets of T cells, such as Th1, Th2, Th17, and Treg cells, its role in follicular helper T (TFH) cells has not yet been elucidated. To determine whether ERα controls TFH response and antibody production, we generated T cell-specific ERα knockout (KO) mice by utilizing the CD4-Cre/ERα flox system (CD4-ERα KO) and then analyzed their phenotype. At approximately 1 year of age, CD4-ERα KO mice spontaneously showed mild autoimmunity with increased autoantibody production and CD4+CD44+CXCR5+Bcl-6+ TFH cells in the mesenteric lymph nodes and spleen. We next immunized 6-8-week-old CD4-ERα KO mice with sheep red blood cells (SRBCs), which resulted in an increased proportion of TFH cells and germinal center (GC) responses. In addition, 17ß-estradiol (E2) treatment decreased TFH responses in wild-type mice and suppressed the mRNA expression of Bcl-6 and IL-21. Finally, we confirmed that the production of high-affinity antigen-specific antibodies and isotype class switching induced by NP-conjugated ovalbumin immunization were elevated in CD4-ERα KO mice under sufficient estrogen conditions. These results collectively demonstrate that the female sex hormone receptor ERα inhibits the TFH cell response and GC reaction to control autoantibody production, which was related to estrogen signaling and autoimmunity.


Assuntos
Autoimunidade/fisiologia , Receptor alfa de Estrogênio/metabolismo , Linfócitos T Auxiliares-Indutores/imunologia , Linfócitos T Auxiliares-Indutores/metabolismo , Animais , Autoimunidade/genética , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Ensaio de Imunoadsorção Enzimática , Receptor alfa de Estrogênio/genética , Feminino , Citometria de Fluxo , Masculino , Camundongos , Microscopia de Fluorescência , Reação em Cadeia da Polimerase em Tempo Real
11.
Opt Express ; 26(8): 10649-10660, 2018 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-29715998

RESUMO

We investigate Huygens' optical vector wave field synthesis scheme for electric dipole metasurfaces with the capability of modulating in-plane polarization and complex amplitude and discuss the practical issues involved in realizing multi-modulation metasurfaces. The proposed Huygens' vector wave field synthesis scheme identifies the vector Airy disk as a synthetic unit element and creates a designed vector optical field by integrating polarization-controlled and complex-modulated Airy disks. The metasurface structure for the proposed vector field synthesis is analyzed in terms of the signal-to-noise ratio of the synthesized field distribution. The design of practical metasurface structures with true vector modulation capability is possible through the analysis of the light field modulation characteristics of various complex modulated geometric phase metasurfaces. It is shown that the regularization of meta-atoms is a key factor that needs to be considered in field synthesis, given that it is essential for a wide range of optical field synthetic applications, including holographic displays, microscopy, and optical lithography.

12.
Opt Lett ; 42(18): 3610-3613, 2017 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-28914914

RESUMO

Huygens' principle states that point sources are the basis of optical wave field generation, and an array of point sources with complex amplitudes that are separated by subwavelength distances can generate a desired optical field distribution. In field synthesis based on the Huygens' principle, the construction of ideal point sources has been overlooked when compared to other elements in optical field synthesis engineering, such as complex modulation. However, the construction of ideal point sources should be considered an important goal because the use of non-ideal point sources generates considerable optical noise in the background of the synthesized field distribution. In this Letter, we investigate Huygens' plasmonic wave field synthesis and its regularization by analyzing the noise features that arise during wave field synthesis based on non-ideal point sources and proposing a novel structure for regularized point source construction. It is shown that the quality of plasmonic wave field synthesis based on the Huygens' principle is greatly improved with the proposed design of a structure that generates a unit point source. Practical field synthesis examples involving plasmonic focusing and Airy beams are presented in support of the proposed design.

13.
Sensors (Basel) ; 17(8)2017 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-28749422

RESUMO

Electromagnetic metamaterials (MMs) and metasurfaces (MSs) are artificial media and surfaces with subwavelength separations of meta-atoms designed for anomalous manipulations of light properties. Owing to large scattering cross-sections of metallic/dielectric meta-atoms, it is possible to not only localize strong electromagnetic fields in deep subwavelength volume but also decompose and analyze incident light signal with ultracompact setup using MMs and MSs. Hence, by probing resonant spectral responses from extremely boosted interactions between analyte layer and optical MMs or MSs, sensing the variation of refractive index has been a popular and practical application in the field of photonics. Moreover, decomposing and analyzing incident light signal can be easily achieved with anisotropic MSs, which can scatter light to different directions according to its polarization or wavelength. In this paper, we present recent advances and potential applications of optical MMs and MSs for refractive index sensing and sensing light properties, which can be easily integrated with various electronic devices. The characteristics and performances of devices are summarized and compared qualitatively with suggestions of design guidelines.

14.
Oncol Lett ; 13(4): 2521-2530, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28454429

RESUMO

Lonicera japonica Thunb. (L. japonica T.) has historically been used in Korean herbal medicine due to its anticancer and protective effects on the respiratory system. In the present study, the polyphenolic compounds in L. japonica T. were investigated using high-performance liquid chromatography coupled with tandem mass spectrometry, and its anticancer effects on A549 non-small-cell lung cancer cells were studied. Polyphenolic compounds potentially inhibit A549 cells in a dose-dependent manner. Flow cytometry and western blot analysis demonstrated that polyphenolic compounds induce apoptosis by regulating the protein expression levels of caspases, poly-(ADP-ribose) polymerase and the B-cell lymphoma-2-associated X-protein/B-cell lymphoma-extra large ratio. Furthermore, polyphenolic compounds inhibited mitochondrial membrane potential activity. Caspase-3 activity was increased in a dose-dependent manner and polyphenolic compounds inhibited the activation of protein kinase B by dephosphorylation. These results suggest that polyphenolic compounds in A549 cells indicate the anticancer activity through the induction of apoptosis.

15.
Opt Express ; 24(20): 22423-22431, 2016 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-27828314

RESUMO

A cavity-aperture has a problem of low transmission efficiency due to its nano-sized aperture despite its potential for plasmonic color filters. In this study, a triple-slit aperture is proposed as the nanoaperture in the center of the cavity-aperture to improve the transmittance. It provides one centered nanoslit and two symmetric wedge structures to each of three cavities corresponding to incident polarization, and induces the strong confinement and transmission of electric fields due to plasmonic resonances at the two types of nanostructures. The transmittance of the triple-slit aperture is theoretically five times and experimentally two times higher than that of a circular aperture. Furthermore, expansive studies on polarization-insensitive nanoapertures with six-fold rotational symmetry will contribute to the development of plasmonic color filters and imaging devices.

16.
Sci Rep ; 6: 33317, 2016 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-27620281

RESUMO

The modulation of near-field signals has recently attracted considerable interest because of demands for the development of nano-scale optical devices that are capable of overcoming the diffraction limit of light. In this paper, we propose a new type of tuneable plasmonic lens that permits the foci of surface plasmon polariton (SPP) signals to be continuously steered by adjusting the input polarization state. The proposed structure consists of multi-lined nanoslit arrays, in which each array is tilted at a different angle to provide polarization sensitivity and the nanoslit size is adjusted to balance the relative amplitudes of the excited SPPs from each line. The nanoslits of each line are designed to focus SPPs at different positions; hence, the SPP focal length can be tuned by modifying the incident polarization state. Unlike in previously reported studies, our method enables plasmonic foci to be continuously varied with a smooth change in the incident linear polarization state. The proposed structures provide a novel degree of freedom in the multiplexing of near fields. Such characteristics are expected to enable the realization of active SPP modulation that can be applied in near-field imaging, optical tweezing systems, and integrated nano-devices.

17.
Int J Mol Sci ; 17(8)2016 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-27548145

RESUMO

Peroxisome proliferator-activated receptor gamma (PPARγ) has recently been recognized to regulate adaptive immunity through Th17 differentiation, Treg functions, and TFH responses. However, its role in adaptive immunity and autoimmune disease is still not clear, possibly due to sexual differences. Here, we investigated in vitro treatment study with the PPARγ agonist pioglitazone to compare Th1, Th2, and Th17 differentiation in male and female mouse splenic T cells. Pioglitazone treatment significantly inhibited various effector T cell differentiations including Th1, Th2, and Th17 cells from female naïve T cells, but it selectively reduced IL-17 production in male Th17 differentiation. Interestingly, pioglitazone and estradiol (E2) co-treatment of T cells in males inhibited differentiation of Th1, Th2, and Th17 cells, suggesting a mechanism for the greater sensitivity of PPARγ to ligand treatment in the regulation of effector T cell differentiation in females. Collectively, these results demonstrate that PPARγ selectively inhibits Th17 differentiation only in male T cells and modulates Th1, Th2, and Th17 differentiation in female T cells based on different level of estrogen exposure. Accordingly, PPARγ could be an important immune regulator of sexual differences in adaptive immunity.


Assuntos
PPAR gama/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Estrogênios/farmacologia , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , PPAR gama/agonistas , Pioglitazona , Fatores Sexuais , Células Th1/citologia , Células Th1/efeitos dos fármacos , Células Th1/metabolismo , Células Th17/citologia , Células Th17/efeitos dos fármacos , Células Th17/metabolismo , Células Th2/citologia , Células Th2/efeitos dos fármacos , Células Th2/metabolismo , Tiazolidinedionas/farmacologia
18.
Sci Rep ; 6: 28495, 2016 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-27335315

RESUMO

Peroxisome proliferator-activated receptor gamma (PPARγ), a master regulator of adipocyte differentiation, has recently been connected with effector T cells, though its role is still not clear. Here, we investigated the roles of PPARγ in follicular helper T (TFH) cell responses regarding gender specificity. NP-OVA immunization in female but not male CD4-PPARγ(KO) mice induced higher proportions of TFH cells and germinal center (GC) B cells following immunization than were seen in wild type mice. Treatment with the PPARγ agonist pioglitazone significantly reduced TFH cell responses in female mice while pioglitazone and estradiol (E2) co-treatment ameliorated TFH cells and GC responses in male mice. E2 treatment significantly enhanced PPARγ expression in male T cells, while T cell activation in the estrus but not in the diestrus stage of the menstrual cycle of females was inhibited by pioglitazone, suggesting that an estrogen-sufficient environment is important for PPARγ-mediated T cell regulation. These results demonstrate gender-based differences in sensitivities of PPARγ in TFH responses. These findings suggest that appropriate function of PPARγ is required in the regulation of female GC responses and that therapeutic strategies for autoimmune diseases using PPARγ agonists need to be tailored accordingly.


Assuntos
Estradiol/farmacologia , Ativação Linfocitária/efeitos dos fármacos , PPAR gama/metabolismo , Animais , Linfócitos B/citologia , Linfócitos B/efeitos dos fármacos , Linfócitos B/metabolismo , Antígenos CD4/deficiência , Antígenos CD4/genética , Feminino , Citometria de Fluxo , Centro Germinativo/efeitos dos fármacos , Centro Germinativo/imunologia , Centro Germinativo/metabolismo , Masculino , Camundongos , Camundongos Knockout , Microscopia de Fluorescência , Nanopartículas/química , Ovalbumina/imunologia , PPAR gama/antagonistas & inibidores , PPAR gama/genética , Pioglitazona , Fatores Sexuais , Linfócitos T Auxiliares-Indutores/citologia , Linfócitos T Auxiliares-Indutores/efeitos dos fármacos , Linfócitos T Auxiliares-Indutores/metabolismo , Tiazolidinedionas/farmacologia
19.
Mol Cell ; 61(6): 859-73, 2016 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-26990989

RESUMO

Dysregulation of MLL complex-mediated histone methylation plays a pivotal role in gene expression associated with diseases, but little is known about cellular factors modulating MLL complex activity. Here, we report that SON, previously known as an RNA splicing factor, controls MLL complex-mediated transcriptional initiation. SON binds to DNA near transcription start sites, interacts with menin, and inhibits MLL complex assembly, resulting in decreased H3K4me3 and transcriptional repression. Importantly, alternatively spliced short isoforms of SON are markedly upregulated in acute myeloid leukemia. The short isoforms compete with full-length SON for chromatin occupancy but lack the menin-binding ability, thereby antagonizing full-length SON function in transcriptional repression while not impairing full-length SON-mediated RNA splicing. Furthermore, overexpression of a short isoform of SON enhances replating potential of hematopoietic progenitors. Our findings define SON as a fine-tuner of the MLL-menin interaction and reveal short SON overexpression as a marker indicating aberrant transcriptional initiation in leukemia.


Assuntos
Proteínas de Ligação a DNA/genética , Histona-Lisina N-Metiltransferase/biossíntese , Leucemia Mieloide Aguda/genética , Proteína de Leucina Linfoide-Mieloide/biossíntese , Proteínas Proto-Oncogênicas/genética , Transcrição Gênica , Processamento Alternativo/genética , Linhagem Celular Tumoral , Cromatina/genética , Proteínas de Ligação a DNA/biossíntese , Regulação Leucêmica da Expressão Gênica , Histona-Lisina N-Metiltransferase/genética , Humanos , Leucemia Mieloide Aguda/patologia , Metilação , Antígenos de Histocompatibilidade Menor , Proteína de Leucina Linfoide-Mieloide/genética , Ligação Proteica , Isoformas de Proteínas/genética , Proteínas Proto-Oncogênicas/metabolismo
20.
Opt Express ; 23(19): 24464-74, 2015 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-26406651

RESUMO

We propose a design of ultra-compact plasmonic coherent perfect absorber (CPA) working in the near-infrared band. The main operating mechanism is the magnetic-dipole resonant coherent absorption in the metal-insulator-metal waveguide, which enables the CPA in the near-infrared band and can be also flexibly adjusted to place the magnetic-dipole resonance at any position in the near-infrared band. Numerical analysis verifies our proposal that the magnetic resonant CPA is crucial for near-IR CPA in the ultra-compact metal-insulator-metal waveguide.

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