RESUMEN
Surface enhanced Raman spectroscopy (SERS) measurements are conventionally performed using assemblies of metal nanostructures on a macro- to micro-sized substrate or by dispersing colloidal metal nanoparticles directly onto the sample of interest. Despite intense use, these methods allow neither the removal of the nanoparticles after a measurement nor a defined confinement of the SERS measurement position. So far, tip enhanced Raman spectroscopy is still the key technique in this regard but not adequate for various samples mainly due to diminished signal enhancement compared to other techniques, poor device fabrication reproducibility, and cumbersome experimental setup requirements. Here, we demonstrate that a rational combination of only four gold nanoparticles (AuNPs) on a DNA origami template, and single silicon nanowires (SiNWs) yield functional optical amplifier nanoprobes for SERS. These nanoscale SERS devices offer a spatial resolution below the diffraction limit of light and still a high electric field intensity enhancement factor ( EF) of about 105 despite of miniaturization.
Asunto(s)
ADN/química , Oro/química , Nanopartículas del Metal/química , Nanocables/química , Silicio/química , Espectrometría Raman/métodos , Azul de Metileno/análisis , Modelos Moleculares , Propiedades de SuperficieRESUMEN
BACKGROUND: Smooth muscle cells are important for atherosclerotic plaque stability. Their proper ability to communicate with the extracellular matrix is crucial for maintaining the correct tissue integrity. In this study, we have investigated the role of ß-sarcoglycan within the matrix-binding dystrophin-glycoprotein complex in the development of atherosclerosis. RESULTS: Atherosclerotic plaque development was significantly reduced in ApoE-deficient mice lacking ß-sarcoglycan, and their plaques contained an increase in differentiated smooth muscle cells. ApoE-deficient mice lacking ß-sarcoglycan showed a reduction in ovarian adipose tissue and adipocyte size, while the total weight of the animals was not significantly different. Western blot analysis of adipose tissues showed a decreased activation of protein kinase B, while that of AMP-activated kinase was increased in mice lacking ß-sarcoglycan. Analysis of plasma in ß-sarcoglycan-deficient mice revealed reduced levels of leptin, adiponectin, insulin, cholesterol, and triglycerides but increased levels of IL-6, IL-17, and TNF-α. CONCLUSIONS: Our results indicate that the dystrophin-glycoprotein complex and ß-sarcoglycan can affect the atherosclerotic process. Furthermore, the results show the effects of ß-sarcoglycan deficiency on adipose tissue and lipid metabolism, which may also have contributed to the atherosclerotic plaque reduction.
Asunto(s)
Enfermedades de la Aorta/prevención & control , Apolipoproteínas E/deficiencia , Aterosclerosis/prevención & control , Músculo Liso Vascular/metabolismo , Miocitos del Músculo Liso/metabolismo , Placa Aterosclerótica , Sarcoglicanos/deficiencia , Proteínas Quinasas Activadas por AMP/metabolismo , Adipocitos/metabolismo , Adipocitos/patología , Adipoquinas/metabolismo , Tejido Adiposo/metabolismo , Tejido Adiposo/patología , Animales , Aorta Torácica/metabolismo , Aorta Torácica/patología , Enfermedades de la Aorta/genética , Enfermedades de la Aorta/metabolismo , Enfermedades de la Aorta/patología , Apolipoproteínas E/genética , Aterosclerosis/genética , Aterosclerosis/metabolismo , Aterosclerosis/patología , Citocinas/metabolismo , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Complejo de Proteínas Asociado a la Distrofina/metabolismo , Femenino , Predisposición Genética a la Enfermedad , Ratones Endogámicos C57BL , Ratones Noqueados , Músculo Liso Vascular/patología , Miocitos del Músculo Liso/patología , Fenotipo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Sarcoglicanos/genéticaRESUMEN
OBJECTIVE: Actin dynamics in vascular smooth muscle is known to regulate contractile differentiation and may play a role in the pathogenesis of vascular disease. However, the list of genes regulated by actin polymerization in smooth muscle remains incomprehensive. Thus, the objective of this study was to identify actin-regulated genes in smooth muscle and to demonstrate the role of these genes in the regulation of vascular smooth muscle phenotype. APPROACH AND RESULTS: Mouse aortic smooth muscle cells were treated with an actin-stabilizing agent, jasplakinolide, and analyzed by microarrays. Several transcripts were upregulated including both known and previously unknown actin-regulated genes. Dystrophin and synaptopodin 2 were selected for further analysis in models of phenotypic modulation and vascular disease. These genes were highly expressed in differentiated versus synthetic smooth muscle and their expression was promoted by the transcription factors myocardin and myocardin-related transcription factor A. Furthermore, the expression of both synaptopodin 2 and dystrophin was significantly reduced in balloon-injured human arteries. Finally, using a dystrophin mutant mdx mouse and synaptopodin 2 knockdown, we demonstrate that these genes are involved in the regulation of smooth muscle differentiation and function. CONCLUSIONS: This study demonstrates novel genes that are promoted by actin polymerization, that regulate smooth muscle function, and that are deregulated in models of vascular disease. Thus, targeting actin polymerization or the genes controlled in this manner can lead to novel therapeutic options against vascular pathologies that involve phenotypic modulation of smooth muscle cells.
Asunto(s)
Actinas/metabolismo , Distrofina/genética , Proteínas de Microfilamentos/genética , Músculo Liso Vascular/metabolismo , Enfermedades Vasculares/genética , Enfermedades Vasculares/metabolismo , Animales , Arterias/lesiones , Células Cultivadas , Expresión Génica , Humanos , Ratones Endogámicos mdx , Ratones Noqueados , Contracción Muscular , Relajación Muscular , Polimerizacion , Transcripción GenéticaRESUMEN
INTRODUCTION: Pain is an unavoidable squeal of orthodontic treatment and it is known to decrease patient compliance and eventually affects treatment results. Numerous methods are available in literature to manage orthodontic pain after activation but they have their own limitations. This has led to exploring further options for management of pain. AIM: The aim of this study was to evaluate the effectiveness of low-level laser therapy (LLLT) in alleviating orthodontic pain after activation. MATERIALS AND METHODS: 20 subjects were randomly divided into an experimental and a control group. Each participant was given a retraction force of 200 gm/cm2/side. Subjects in the experimental group were exposed to low-level laser light at 980 nm and those in the control group were exposed to red LED light as placebo. The pain perceived after 0 hour, 1 hour, 3 hours, 48 hours, and 1 week of activation was recorded by patient using Visual Analog Scale. Statistical analysis was done using Mann-Whitney test. RESULTS: Results of the study showed that pain experienced by the subjects after orthodontic activation was higher in experimental group at T0 than in placebo group. At T1, T2, T4, and T5, the pain experienced by the subjects was less in the experimental group compared to the placebo group. Pain experienced by the subjects in the experimental group at T3 was significantly less as compared to those in the placebo group. CONCLUSION: A single dose of LLLT at 980nm, 2.5 W/cm2, and 600 J is effective in relieving orthodontic pain after activation.
RESUMEN
Dystrophin of the dystrophin-glycoprotein complex connects the actin cytoskeleton to basement membranes and loss of dystrophin results in Duchenne muscular dystrophy. We have previously shown injury-induced neointima formation of the carotid artery in mice with the mdx mutation (causing dystrophin deficiency) to be increased. To investigate the role of dystrophin in intimal recruitment of smooth muscle cells (SMCs) that maintains plaque stability in atherosclerosis we applied a shear stress-modifying cast around the carotid artery of apolipoprotein E (ApoE)-null mice with and without the mdx mutation. The cast induces formation of atherosclerotic plaques of inflammatory and SMC-rich/fibrous phenotypes in regions of low and oscillatory shear stress, respectively. Unexpectedly, presence of the mdx mutation markedly reduced the development of the inflammatory low shear stress plaques. Further characterization of the low shear stress plaques in ApoE-null mdx mice demonstrated reduced infiltration of CD3(+) T cells, less laminin and a higher SMC content. ApoE-null mdx mice were also found to have a reduced fraction of CD3(+) T cells in the spleen and lower levels of cytokines and monocytes in the circulation. The present study is the first to demonstrate a role for dystrophin in atherosclerosis and unexpectedly shows that this primarily involves immune cells.