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1.
Breast Cancer Res ; 25(1): 149, 2023 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-38066611

RESUMO

BACKGROUND: Based on the molecular expression of cancer cells, molecular subtypes of breast cancer have been applied to classify patients for predicting clinical outcomes and prognosis. However, further evidence is needed regarding the influence of molecular subtypes on the efficacy of radiotherapy (RT) after breast-conserving surgery (BCS), particularly in a population-based context. Hence, the present study employed a propensity-score-matched cohort design to investigate the potential role of molecular subtypes in stratifying patient outcomes for post-BCS RT and to identify the specific clinical benefits that may emerge. METHODS: From 2006 to 2019, the present study included 59,502 breast cancer patients who underwent BCS from the Taiwan National Health Insurance Research Database. Propensity scores were utilized to match confounding variables between patients with and without RT within each subtype of breast cancer, namely luminal A, luminal B/HER2-negative, luminal B/HER2-positive, basal-like, and HER2-enriched ones. Several clinical outcomes were assessed, in terms of local recurrence (LR), regional recurrence (RR), distant metastasis (DM), disease-free survival (DFS), and overall survival (OS). RESULTS: After post-BCS RT, patients with luminal A and luminal B/HER2-positive breast cancers exhibited a decrease in LR (adjusted hazard ratio [aHR] = 0.18, p < 0.0001; and, 0.24, p = 0.0049, respectively). Furthermore, reduced RR and improved DFS were observed in patients with luminal A (aHR = 0.15, p = 0.0004; and 0.29, p < 0.0001), luminal B/HER2-negative (aHR = 0.06, p = 0.0093; and, 0.46, p = 0.028), and luminal B/HER2-positive (aHR = 0.14, p = 0.01; and, 0.38, p < 0.0001) breast cancers. Notably, OS benefits were found in patients with luminal A (aHR = 0.62, p = 0.002), luminal B/HER2-negative (aHR = 0.30, p < 0.0001), basal-like (aHR = 0.40, p < 0.0001), and HER2-enriched (aHR = 0.50, p = 0.03), but not luminal B/HER2-positive diseases. Remarkably, when considering DM, luminal A patients who received RT demonstrated a lower cumulative incidence of DM than those without RT (p = 0.02). CONCLUSION: In patients with luminal A breast cancer who undergo BCS, RT could decrease the likelihood of tumor metastasis. After RT, the tumor's hormone receptor status may predict tumor control regarding LR, RR, and DFS. Besides, the HER2 status of luminal breast cancer patients may serve as an additional predictor of OS after post-BCS RT. However, further prospective studies are required to validate these findings.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/genética , Neoplasias da Mama/radioterapia , Neoplasias da Mama/cirurgia , Estudos de Coortes , Mastectomia Segmentar , Pontuação de Propensão , Receptor ErbB-2/metabolismo , Prognóstico , Estudos Retrospectivos , Recidiva Local de Neoplasia/patologia
2.
Gut ; 70(10): 1954-1964, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33208407

RESUMO

OBJECTIVE: Lipotoxic hepatocyte injury is a primary event in non-alcoholic steatohepatitis (NASH), but the mechanisms of lipotoxicity are not fully defined. Sphingolipids and free cholesterol (FC) mediate hepatocyte injury, but their link in NASH has not been explored. We examined the role of free cholesterol and sphingomyelin synthases (SMSs) that generate sphingomyelin (SM) and diacylglycerol (DAG) in hepatocyte pyroptosis, a specific form of programmed cell death associated with inflammasome activation, and NASH. DESIGN: Wild-type C57BL/6J mice were fed a high fat and high cholesterol diet (HFHCD) to induce NASH. Hepatic SMS1 and SMS2 expressions were examined in various mouse models including HFHCD-fed mice and patients with NASH. Pyroptosis was estimated by the generation of the gasdermin-D N-terminal fragment. NASH susceptibility and pyroptosis were examined following knockdown of SMS1, protein kinase Cδ (PKCδ), or the NLR family CARD domain-containing protein 4 (NLRC4). RESULTS: HFHCD increased the hepatic levels of SM and DAG while decreasing the level of phosphatidylcholine. Hepatic expression of Sms1 but not Sms2 was higher in mouse models and patients with NASH. FC in hepatocytes induced Sms1 expression, and Sms1 knockdown prevented HFHCD-induced NASH. DAG produced by SMS1 activated PKCδ and NLRC4 inflammasome to induce hepatocyte pyroptosis. Depletion of Nlrc4 prevented hepatocyte pyroptosis and the development of NASH. Conditioned media from pyroptotic hepatocytes activated the NOD-like receptor family pyrin domain containing 3 inflammasome (NLRP3) in Kupffer cells, but Nlrp3 knockout mice were not protected against HFHCD-induced hepatocyte pyroptosis. CONCLUSION: SMS1 mediates hepatocyte pyroptosis through a novel DAG-PKCδ-NLRC4 axis and holds promise as a therapeutic target for NASH.


Assuntos
Hepatócitos/enzimologia , Hepatopatia Gordurosa não Alcoólica/enzimologia , Piroptose , Transferases (Outros Grupos de Fosfato Substituídos)/metabolismo , Animais , Modelos Animais de Doenças , Masculino , Camundongos , Camundongos Endogâmicos C57BL
3.
Int J Mol Sci ; 22(23)2021 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-34884937

RESUMO

Approximately 1 million cases of leptospirosis, an emerging infectious zoonotic disease, are reported each year. Pathogenic Leptospira species express leucine-rich repeat (LRR) proteins that are rarely expressed in non-pathogenic Leptospira species. The LRR domain-containing protein family is vital for the virulence of pathogenic Leptospira species. In this study, the biological mechanisms of an essential LRR domain protein from pathogenic Leptospira were examined. The effects of Leptospira and recombinant LRR20 (rLRR20) on the expression levels of factors involved in signal transduction were examined using microarray, quantitative real-time polymerase chain reaction, and western blotting. The secreted biomarkers were measured using an enzyme-linked immunosorbent assay. rLRR20 colocalized with E-cadherin on the cell surface and activated the downstream transcription factor ß-catenin, which subsequently promoted the expression of MMP7, a kidney injury biomarker. Additionally, MMP7 inhibitors were used to demonstrate that the secreted MMP7 degrades surface E-cadherin. This feedback inhibition mechanism downregulated surface E-cadherin expression and inhibited the colonization of Leptospira. The degradation of surface E-cadherin activated the NF-κB signal transduction pathway. Leptospirosis-associated acute kidney injury is associated with the secretion of NGAL, a downstream upregulated biomarker of the NF-κB signal transduction pathway. A working model was proposed to illustrate the crosstalk between E-cadherin/ß-catenin and NF-κB signal transduction pathways during Leptospira infection. Thus, rLRR20 of Leptospira induces kidney injury in host cells and inhibits the adhesion and invasion of Leptospira through the upregulation of MMP7 and NGAL.


Assuntos
Antígenos CD/metabolismo , Caderinas/metabolismo , Interações Hospedeiro-Patógeno/fisiologia , Leptospirose/metabolismo , NF-kappa B/metabolismo , beta Catenina/metabolismo , Antígenos CD/genética , Caderinas/genética , Regulação da Expressão Gênica , Humanos , Leptospira/metabolismo , Leptospira/patogenicidade , Leptospirose/microbiologia , Proteínas de Repetições Ricas em Leucina/genética , Proteínas de Repetições Ricas em Leucina/metabolismo , Lipocalina-2/metabolismo , Metaloproteinase 7 da Matriz/metabolismo , Transporte Proteico , Transdução de Sinais , beta Catenina/genética
4.
Opt Express ; 27(25): 36046-36058, 2019 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-31873391

RESUMO

Photon management plays a vital role in the power conversion efficiency of III-V semiconductor solar cells. However, the photon recycling characteristics of GaAs-based multi-quantum-well (MQW) solar cells employed different optical designs had yet been fully explored. In this work, we investigate the impact of the spectrally selective filter (SSF) and distributed Bragg reflector (DBR) on the photovoltaic characteristics of single-junction, strain-balanced In0.1Ga0.9As/ GaAs0.85P0.15 MQW solar cells. Specifically, the SSFs with cutoff wavelengths of 880, 910, and 940 nm are designed and implemented on MQW solar cells with and without the incorporation of a rear DBR. Photon confinement in the vertical direction is verified based on the characterizations of reflectance, electroluminescence, and external quantum efficiency. We show that the photon confinement reduces the saturation current density, up to 26 times and 3 times for the 880 nm SSF-MQW and SSF-MQW-DBR devices, respectively, compared to that of the 940 nm devices. Furthermore, by comparing the SSF-MQW-DBR solar cells under simulated one-sun and concentrated illumination conditions, the open-circuit voltage exhibits a maximal net increase for the 910 nm SSF due to tradeoff between the short-circuit and saturation current density. The proposed SSF design may offer a viable approach to boost the performance of GaAs-based MQW solar cells.

5.
World J Urol ; 37(9): 1949-1957, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30539227

RESUMO

PURPOSE: To analyze the trifecta outcome (functional, anatomical, and surgical aspects) of surgical reconstruction for ureteral lesions and investigate the factors affecting the success rate of such reconstruction. METHODS: We retrospectively reviewed the data of patients who underwent ureteral reconstruction at our institute between March 2007 and November 2016. Patient profiles, surgical methods, complications, ureteral stenting, laboratory data, and image studies were collected. The trifecta outcome was defined as preserved renal function, no progression of hydronephrosis, and no long-term stenting. The primary endpoint was the percentage of patients who achieved the trifecta outcome. The secondary endpoint was risk factors for trifecta outcome failure. RESULTS: We retrospectively reviewed 178 adult patients who had undergone ureteral reconstruction. The median follow-up period was 37.4 months. In total, 70 (39.3%) patients had iatrogenic ureteral injuries and 108 (60.7%) patients had non-iatrogenic ureteral lesions. Overall, 70% of the patients achieved the trifecta outcome after ureteral reconstruction. A multivariate analysis revealed that risk factors for trifecta failure were malignant diseases [odds ratio (OR) 2.93, p = 0.005], a history of pelvic radiation (OR 3.08, p = 0.032), preoperative estimated glomerular filtration rate < 60 (OR 2.52, p = 0.039), and a type of reconstruction ureteroureterostomy (OR 2.99, p = 0.014). CONCLUSIONS: Trifecta outcome could be used to evaluate the ureteral reconstruction in iatrogenic injury and non-iatrogenic ureteral lesions. This study revealed several risk factors that affected the trifecta outcome.


Assuntos
Complicações Intraoperatórias/cirurgia , Ureter/lesões , Ureter/cirurgia , Adulto , Feminino , Humanos , Doença Iatrogênica , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Centros de Atenção Terciária , Fatores de Tempo , Resultado do Tratamento , Procedimentos Cirúrgicos Urológicos/métodos
6.
Phys Chem Chem Phys ; 21(18): 9581-9589, 2019 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-31020972

RESUMO

Sn is one of the promising Li ion battery anode materials with high theoretical capacity and mechanical properties that allow for effective relaxation of Li diffusion-induced stresses. Sn is a low melting point metal with a low modulus and strength and has the ability to relax stresses via plasticity and creep deformations. In this study, concentration-dependent material properties are used in numerical simulations to model the Li diffusion-induced stress evolution in Sn micropillars. Simulation results using concentration-dependent material properties resulted in a completely different failure mode in comparison to that of concentration-independent simulation results. Tensile hoop stress needed for crack propagation was analyzed to be at the core for concentration-independent material properties, and switched to being at the surface for concentration-dependent simulation results. In addition, by incorporating these maximum tensile DIS results, the critical size for the failure of Sn micropillars was determined to be 5.3 µm at C/10 charging rate. This was then correlated with experimental observations, where fracture occurred in Sn micropillars with sizes larger than 6 µm, while 4.4 µm sized Sn micropillars survived the lithiation cycle.

7.
Biol Pharm Bull ; 42(8): 1322-1331, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31366867

RESUMO

Urban particulate matter (UPM) is atmospheric particulate samples obtained from industrialized urban areas. It is known that pulmonary fibrosis can result directly or indirectly from particulate matter. In this study, the protective effect of chebulic acid (CA) against UPM-induced epithelial-mesenchymal transition (EMT) in the pulmonary alveolar epithelial (PAE) cells were investigated. Our findings revealed that PAE cells were changed from the epithelial phenotype to mesenchymal one after exposure to UPM. Furthermore, co-treatment and post-treatment of CA inhibited EMT progression. Especially the key epithelial marker, E-cadherin, was down-regulated by UPM and recovered by CA. Also, gelatin zymogram showed that the activity of matrix metalloproteinase (MMP)-2 and MMP-9 was decreased by co-treatment and post-treatment of CA. Further investigation revealed that CA attenuated UPM-stimulated PAE cells invasion ability. These data showed that UPM promoted PAE cells invasion, reactive oxygen species-mediated extracellular matrix degradation and CA reduced the potential health risks associated with UPM.


Assuntos
Poluentes Atmosféricos/toxicidade , Benzopiranos/farmacologia , Células Epiteliais/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Material Particulado/toxicidade , Substâncias Protetoras/farmacologia , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Células Epiteliais/fisiologia , Humanos , Alvéolos Pulmonares , Espécies Reativas de Oxigênio/metabolismo
9.
Microb Pathog ; 111: 292-297, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28867629

RESUMO

Hand, Foot and mouth disease (HFMD) is a common disease with high infectivity for children, and enterovirus 71 (EV71) is one of the main pathogens to cause the type of illness. Therefore, the aim of this study was to propose a rapid and effective technique for detecting EV71 directly based on the mechanism of biological intermolecular force by using atomic force microscopy (AFM). At first, we coated EV71 particles on the mica surface and made the EV71 antibodies (anti-EV71) fixed on the AFM tip by means of several chemical procedures. Then, AFM chemically modified tip was applied to measure the unbinding forces between EV71 and anti-EV71 by contact mode. Finally, by using AFM imaging calculating software, the EV71 particle size (mean±SD) was 31.36±3.87 nm (n = 200) and this result was concordance with previous literature. Besides, the force (mean±SD) between EV71 antigen and antibody complex was 336.9±64.7 pN. The force (mean±SD) between anti-EV71 and non-specific specimens was 47.1±15.1 pN and was significantly smaller (P < 0.05). Apparently, the results show that we can precisely identify EV71 infection among the samples by measuring the force magnitude and observing the occurrence of EV71/anti-EV71 unbinding events. Therefore, the combination of AFM system and the chemically modified tip has the potential to be a rapid and effective method for detecting EV71 directly.


Assuntos
Anticorpos Antivirais/análise , Antígenos Virais/análise , Técnicas Biossensoriais/métodos , Enterovirus Humano A/isolamento & purificação , Infecções por Enterovirus/virologia , Microscopia de Força Atômica/métodos , Anticorpos Antivirais/imunologia , Antígenos Virais/imunologia , Técnicas Biossensoriais/instrumentação , Enterovirus Humano A/química , Enterovirus Humano A/imunologia , Humanos , Microscopia de Força Atômica/instrumentação
10.
BMC Complement Altern Med ; 17(1): 66, 2017 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-28109289

RESUMO

BACKGROUND: Plantago asiatica has been traditionally used for traditional medicine around East Asia. Plantamajoside (PM), which is isolated from this plant, is known for biological properties including anti-inflammation and antioxidant activity. To demonstrate the biological activity of PM against endothelial dysfunction induced by advanced glycation end-products (AGEs), a cellular inflammatory mechanism system was evaluated in human umbilical vein endothelial cells (HUVECs). METHODS: We obtained PM through previous research in our laboratory. We formed the AGEs from bovine serum albumin with glyceraldehyde in the dark for seven days. To confirm the modulation of the inflammatory mechanism in endothelial dysfunction, we quantified the various pro-inflammatory cytokines and endothelial dysfunction-related proteins in the HUVECs with Western blotting and with real-time and quantitative real-time polymerase chain reactions. RESULTS: Co-treatment with PM and AGEs significantly suppressed inflammatory cytokines and adhesion molecule expression. Moreover, the PM treatment for down-regulated inflammatory signals and blocked monocyte adhesion on the HUVECs. CONCLUSIONS: Theses results demonstrated that PM, as a potential natural compound, protects AGE-induced endothelial cells against inflammatory cellular dysfunction.


Assuntos
Catecóis/farmacologia , Glucosídeos/farmacologia , Produtos Finais de Glicação Avançada/metabolismo , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , NF-kappa B/metabolismo , Preparações de Plantas/uso terapêutico , Plantago/química , Animais , Catecóis/toxicidade , Bovinos , Moléculas de Adesão Celular/metabolismo , Citocinas/metabolismo , Sequestradores de Radicais Livres/farmacologia , Glucosídeos/toxicidade , Gliceraldeído/farmacologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Transdução de Sinais/efeitos dos fármacos
11.
BMC Complement Altern Med ; 17(1): 373, 2017 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-28724416

RESUMO

BACKGROUND: Chebulic acid (CA) isolated from T. chebula, which has been reported for treating asthma, as a potent anti-oxidant resources. Exposure to ambient urban particulate matter (UPM) considered as a risk for cardiopulmonary vascular dysfunction. To investigate the protective effect of CA against UPM-mediated collapse of the pulmonary alveolar epithelial (PAE) cell (NCI-H441), barrier integrity parameters, and their elements were evaluated in PAE. METHODS: CA was acquired from the laboratory previous reports. UPM was obtained from the National Institutes of Standards and Technology, and these were collected in St. Louis, MO, over a 24-month period and used as a standard reference. To confirm the protection of PAE barrier integrity, paracellular permeability and the junctional molecules were estimated with determination of transepithelial electrical resistance, Western Blotting, RT-PCR, and fluorescent staining. RESULTS: UPM aggravated the generation of reactive oxygen species (ROS) in PAE and also decreased mRNA and protein levels of junction molecules and barrier integrity in NCI-H441. However, CA repressed the ROS in PAE, also improved barrier integrity by protecting the junctional parameters in NCI-H411. CONCLUSIONS: These data showed that CA resulted in decreased UPM-induced ROS formation, and the protected the integrity of the tight junctions against UPM exposure to PAE barrier.


Assuntos
Células Epiteliais Alveolares/efeitos dos fármacos , Benzopiranos/farmacologia , Inflamação/prevenção & controle , Material Particulado/efeitos adversos , Fitoterapia , Terminalia/química , Junções Íntimas/efeitos dos fármacos , Poluição do Ar/efeitos adversos , Células Epiteliais Alveolares/metabolismo , Células Epiteliais Alveolares/patologia , Antiasmáticos/farmacologia , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Linhagem Celular , Citocinas/metabolismo , Humanos , Inflamação/metabolismo , Pulmão/citologia , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Pulmão/patologia , Missouri , Estresse Oxidativo/efeitos dos fármacos , Permeabilidade , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , RNA Mensageiro/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteínas de Junções Íntimas/genética , Proteínas de Junções Íntimas/metabolismo , Junções Íntimas/metabolismo , Junções Íntimas/patologia
12.
J Synchrotron Radiat ; 23(Pt 5): 1237-40, 2016 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-27577781

RESUMO

An alignment method for correction of the axial and radial runout errors of the rotation stage in X-ray phase-contrast computed tomography has been developed. Only intensity information was used, without extra hardware or complicated calculation. Notably, the method, as demonstrated herein, can utilize the halo artifact to determine displacement.

13.
J Synchrotron Radiat ; 23(Pt 4): 1024-9, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27359152

RESUMO

A new method of phase-shifting digital holography is demonstrated in the hard X-ray region. An in-line-type phase-shifting holography setup was installed in a 6.80 keV hard X-ray synchrotron beamline. By placing a phase plate consisting of a hole and a band at the focusing point of a Fresnel lens, the relative phase of the reference and objective beams could be successfully shifted for use with a three-step phase-shift algorithm. The system was verified by measuring the shape of a gold test pattern and a silica sphere.

14.
Planta Med ; 82(1-2): 46-57, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26308358

RESUMO

During hyperglycemia, the first step toward the formation of advanced glycation end products is the nonenzymatic glycation between the carbonyl group of a sugar and the primary amino group of a protein. Advanced glycation end products are then produced through more complex reactions. Reactive oxygen species derived from advanced glycation end products may play a key role in inflammation of the endothelium, leading to the complications seen in diabetes. Glycolaldehyde-induced advanced glycation end products have been reported to express proinflammatory cytokines, such as tumor necrosis factor-α and interleukin-1ß. This study focused on Capsosiphon fulvescens, a Capsosiphonaceae type of green algae that has shown potential as a functional food material. Pheophorbide a, an anti-glycation compound, was isolated from C. fulvescens by extraction using a mixture of ethanol and water, followed by column fractionation of the resulting extract. The compound separated from C. fulvescens was identified by means of high-performance liquid chromatography combined with mass spectrometry. Pheophorbide a showed scavenging activity of the intracellular reactive oxygen species as well as monocyte adhesiveness inhibitory activity on the human myelomonocytic cell line (THP-1) and human umbilical vein endothelial cells cocultivation system. The mRNA levels of inflammation-related genes such as monocyte chemoattractant protein-1 and interleukin-6 were significantly decreased by pheophorbide a, and advanced glycation end products-stimulated tumor necrosis factor-α and interleukin-1ß were downregulated as well. These results indicate that pheophorbide a has significant reactive oxygen species-scavenging activity, monocyte adhesive inhibitory activity, and downregulatory activity of cytokines related to inflammation affecting the endothelium. Pheophorbide a could therefore be a promising candidate for modulating endothelial cell dysfunction.


Assuntos
Clorofila/análogos & derivados , Clorófitas/química , Células Endoteliais/efeitos dos fármacos , Produtos Finais de Glicação Avançada/antagonistas & inibidores , Aterosclerose/prevenção & controle , Adesão Celular , Clorofila/química , Clorofila/isolamento & purificação , Clorofila/farmacologia , Citocinas/biossíntese , Células Endoteliais da Veia Umbilical Humana , Humanos , Inflamação , Monócitos/metabolismo , Espécies Reativas de Oxigênio/metabolismo
15.
Opt Express ; 22(5): A295-300, 2014 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-24800285

RESUMO

Biomimetic nanostructures have shown to enhance the optical absorption of Ga(0.5)In(0.5)P/GaAs/Ge triple junction solar cells due to excellent antireflective (AR) properties that, however, are highly dependent on their geometric dimensions. In practice, it is challenging to control fabrication conditions which produce nanostructures in ideal periodic arrangements and with tapered side-wall profiles, leading to sacrificed AR properties and solar cell performance. In this work, we introduce compound biomimetic nanostructures created by depositing a layer of silicon dioxide (SiO(2)) on top of titanium dioxide (TiO(2)) nanostructures for triple junction solar cells. The device exhibits photogenerated current and power conversion efficiency that are enhanced by ~8.9% and ~6.4%, respectively, after deposition due to their improved antireflection characteristics. We further investigate and verify the optical properties of compound structures via a rigorous coupled wave analysis model. The additional SiO(2) layer not only improves the geometric profile, but also serves as a double-layer dielectric coating. It is concluded that the compound biomimetic nanostructures exhibit superior AR properties that are relatively insensitive to fabrication constraints. Therefore, the compound approach can be widely adopted for versatile optoelectronic devices and applications.

16.
Opt Express ; 22 Suppl 2: A295-300, 2014 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-24922238

RESUMO

Biomimetic nanostructures have shown to enhance the optical absorption of Ga0.5In0.5P/GaAs/Ge triple junction solar cells due to excellent antireflective (AR) properties that, however, are highly dependent on their geometric dimensions. In practice, it is challenging to control fabrication conditions which produce nanostructures in ideal periodic arrangements and with tapered side-wall profiles, leading to sacrificed AR properties and solar cell performance. In this work, we introduce compound biomimetic nanostructures created by depositing a layer of silicon dioxide (SiO2) on top of titanium dioxide (TiO2) nanostructures for triple junction solar cells. The device exhibits photogenerated current and power conversion efficiency that are enhanced by ~8.9% and ~6.4%, respectively, after deposition due to their improved antireflection characteristics. We further investigate and verify the optical properties of compound structures via a rigorous coupled wave analysis model. The additional SiO2 layer not only improves the geometric profile, but also serves as a double-layer dielectric coating. It is concluded that the compound biomimetic nanostructures exhibit superior AR properties that are relatively insensitive to fabrication constraints. Therefore, the compound approach can be widely adopted for versatile optoelectronic devices and applications.

17.
Biosci Biotechnol Biochem ; 77(1): 58-64, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23291772

RESUMO

Considering the growing evidence of the presence of antioxidant compounds in plant extracts, the objectives of this study were to identify antioxidant compounds in Lindera obtusiloba Blume (Lauraceae) and to evaluate their antimelanogenic activities on B16F10 melanoma cells. Organic solvent fractions were separated from L. obtusiloba extracts (LOE). The ethyl acetate fraction (LOE-E) was significantly active against oxidative damage induced by tert-butyl hydroperoxide in primary rat hepatocytes. Two single purified compounds, quercitrin (quercetin-3-O-α-L-rhamnopyranoside) and afzelin (kaempferol-3-O-α-L-rhamnoside), were identified by HPLC and NMR. These compounds were evaluated for antioxidant activities by 1,1-diphenyl 2-picrylhydrazyl (DPPH) radical scavenging assay and ferric reducing antioxidant power (FRAP) assay, and for their antimelanogenic activities by tyrosinase inhibitory assay melanin formation inhibition assay and Western bolt analysis for the signaling pathway. The significant effects of quercitrin on antioxidant and antimelanogenic activities, and signal modulation of ERK and MITF in B16F10 melanoma cells were observed. This is the first report to identify quercitrin in L. obtusiloba and its whitening effect.


Assuntos
Antioxidantes/isolamento & purificação , Lindera/química , Manosídeos/isolamento & purificação , Melaninas/antagonistas & inibidores , Extratos Vegetais/isolamento & purificação , Proantocianidinas/isolamento & purificação , Quercetina/análogos & derivados , Acetatos/química , Animais , Antioxidantes/farmacologia , Compostos de Bifenilo/antagonistas & inibidores , Linhagem Celular Tumoral , MAP Quinases Reguladas por Sinal Extracelular/genética , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Expressão Gênica/efeitos dos fármacos , Hepatócitos/citologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Masculino , Manosídeos/farmacologia , Melaninas/biossíntese , Melanoma Experimental/metabolismo , Fator de Transcrição Associado à Microftalmia/genética , Fator de Transcrição Associado à Microftalmia/metabolismo , Monofenol Mono-Oxigenase/antagonistas & inibidores , Monofenol Mono-Oxigenase/metabolismo , Picratos/antagonistas & inibidores , Extratos Vegetais/farmacologia , Cultura Primária de Células , Proantocianidinas/farmacologia , Quercetina/isolamento & purificação , Quercetina/farmacologia , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , terc-Butil Hidroperóxido/farmacologia
18.
Biosci Biotechnol Biochem ; 77(4): 714-21, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23563562

RESUMO

Unripe green apples contain condensed tannins at 10 times higher levels than ripe apples. Tannin not only has strong antioxidant activity, but also an astringent property. In this study, we investigated the effects of green apple rind (GAR) extracts in reducing facial pores and sebum secretion. Among the GAR extracts, the 70% ethanol GAR extract showed the highest antioxidant activity and tannin content. Hence, it was further fractionated with different solvents. Among these rind solvent fractions, the ethyl acetate fraction of the extract (GAR-E) showed astringent activity. Additionally, it exhibited inhibitory effects on 5-α reductase, and induced type 1 collagen and involucrin synthesis. These results suggest that GAR-E can be applied in cosmetics to reduce facial pore size and sebum secretion.


Assuntos
Inibidores de 5-alfa Redutase/farmacologia , Antioxidantes/farmacologia , Colestenona 5 alfa-Redutase/antagonistas & inibidores , Fibroblastos/efeitos dos fármacos , Queratinócitos/efeitos dos fármacos , Malus/química , Extratos Vegetais/farmacologia , Inibidores de 5-alfa Redutase/química , Antioxidantes/química , Linhagem Celular , Colestenona 5 alfa-Redutase/genética , Colágeno Tipo I/biossíntese , Fibroblastos/metabolismo , Flavonoides/análise , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Humanos , Queratinócitos/metabolismo , Extratos Vegetais/química , Precursores de Proteínas/biossíntese , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Taninos/análise
19.
Pharmaceuticals (Basel) ; 16(8)2023 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-37631101

RESUMO

We investigated whether hyaluronic acid (HA) injections can ameliorate ultrasound-detected synovitis in knee osteoarthritis (OA). We recruited 103 patients with symptomatic knee OA and ultrasound-detected synovitis and performed two ultrasound-guided fluid drainage procedures, followed by the administration of a low-molecular-weight HA injection (2.5 mL) in the subpatellar bursa, at a 2-week interval. Knee ultrasound imaging evaluations were performed before injection (baseline) and at 1 and 6 months after the second injection and included the measurements of synovial vascularity by using color Doppler ultrasound, synovial fluid depth over the suprapatellar bursa (SF), and synovial hypertrophy (SH). Initial clinical assessments included a visual analog scale (VAS) and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). VAS scores decreased significantly at both 1-month and 6-month evaluations (p < 0.001). WOMAC scores also significantly decreased at 1 month (p < 0.001), but not at 6 months (p = 0.23). The ultrasound parameters did not significantly change, except color Doppler grading, which tended to decrease at the 6-month evaluation (p = 0.059). Our findings revealed that two ultrasound-guided HA injections following fluid drainage improved pain and knee function but did not considerably influence imaging-detected synovitis in patients with knee OA.

20.
Biol Pharm Bull ; 35(2): 260-4, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22293359

RESUMO

Gold nanoparticles (GNPs) have been reported to exhibit a variety of biological effects including anti-inflammatory and anti-oxidant activities. The extent of an in vitro glycation reaction mixture of collagen and glycolaldehyde was assayed to investigate the inhibition of glycolaldehye-derived advanced glycation end products (glycol-AGEs) formation with GNPs in collagen, which is a major protein component of the human dermis. GNP-treated collagen showed significantly less glycation (56.3 ± 4.2%) than an untreated glycation control. Moreover, GNP-treated glycation in a collagen lattice model significantly decreased the AGEs distribution in the model system. Taken together, these results suggest that GNPs have the potential for use in the prevention of glycation-induced skin aging.


Assuntos
Colágeno/química , Produtos Finais de Glicação Avançada/química , Ouro/química , Nanopartículas/química , Glicosilação , Microscopia Eletrônica de Transmissão , Nanopartículas/ultraestrutura
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