295 research outputs found

    Efeito do naftaleno sobre a atividade do receptor gama ativado por proliferadores peroxissomais e a adipogênese em cultura

    Get PDF
    Monografia (graduação)—Universidade de Brasília, Faculdade de Ciências da Saúde, 2016.Os desreguladores endócrinos (DEs) são substâncias presentes no ambiente, alimentos ou produtos de consumo humano que podem mimetizar ou interferir no sistema endócrino no organismo humano e, consequentemente, afetar as funções dos tecidos e/ou órgãos, sendo que um dos seus principais alvos são os chamados receptores nucleares. Estudos mostram que os DEs possuem relação com o aumento da incidência ou progressão de algumas doenças tais como obesidade, diabetes, depressão e alguns tipos de câncer. Dentre essas doenças, destaca-se a obesidade, cuja prevalência aumentou significativamente nos últimos 30 anos, afetando cerca de 8% da população mundial. As fontes de exposição aos DEs incluem dieta; medicamentos e correlatos farmacêuticos; produtos de limpeza e pesticidas (inseticidas, fungicidas e acaricidas). Dessa forma, procura-se identificar os possíveis desreguladores que possuem efeitos obesogênicos, sendo que o elemento de interesse do presente estudo é o naftaleno, um hidrocarboneto aromático policíclico comumente presente na composição repelentes de insetos e cigarros e pouco explorado na literatura. Seu efeito adipogênico em cultura foi investigado em duas linhagens celulares: 3T3-L1 (pré-adipócitos murinos) e C3H10T1/2 (células mesenquimais murinas) e no receptor gama ativado por proliferadores peroxissomais (PPARγ).Endocrine disruptors (EDs) are substances that can be found in the environment, food or products of human consumption, which mimic or interfere with the body’s endocrine system and, consequently, affect the functions of tissues and organs, with one of its major targets called nuclear receptors. Studies show that there is a correlation between EDs and the increasing incidence or progression of certain diseases such as obesity, diabetes, depression and certain types of cancer. Obesity rates, in particular, have increased significantly over the past 30 years, affecting about 8% of the world population. The sources of exposure of EDs include diet; medicinal and pharmaceutical products; cleaning products and pesticides (insecticides, fungicides and acaricides). Thus, the goal is to identify potential disruptors that have obesogenic effects and the element of interest of the present study is naphthalene, an aromatic hydrocarbon polycyclic, which is little addressed in the literature and commonly present in the composition of insect repellents and cigarettes. The adipogenic effect of naphthalene was investigated in two cell lines: 3T3-L1 (murine preadipocytes) and C3H10T1/2 (murine mesenchymal cells) and also in the activity of peroxisome proliferator-activated receptor gamma (PPARγ)

    Determining the Optical Geometry of a Gold Semi-Shell under the Kretschmann Configuration

    Get PDF
    Dielectric nanoparticles coated with metals (half-shell or semi-shell structures) have attracted attention as potential composite plasmonic nanomaterials with large optical anisotropy and absorption cross-sections. Structures approximately 100 nm in size can excite plasmons in the visible and near-infrared ranges, highlighting their distinct optical properties. This study employed metal semi-shell structures (metal: gold, dielectric: silica) in the Kretschmann configuration to experimentally and numerically demonstrate the optical determination of single-structure orientations through a finite-difference time-domain method. Gold semi-shell structures were fabricated through deposition and etching. These structures were removed from their substrate in ultrapure water and randomly dropped onto a thin gold substrate. In the single structure, we experimentally observed changes in the scattering light spectrum based on the optical geometry of the gold semi-shell at wavelengths ranging from 530 to 700 nm. The obtained results closely resembled those of a simulation and confirmed the presence of eigenmodes in the orientation through electric field analysis. These observations allow for the cost-effective and rapid determination of the orientations of numerous structures that are approximately 100 nm in size, solely through optical methods. This technique is a valuable development for measurement applications in nanostructure orientation control and functionality enhancement

    Probable association of T Tauri stars with the L1014 dense core

    Get PDF
    Using the Wide Field Grism Spectrograph 2 (WFGS2), we have carried out slit-less spectroscopy, g'r'i' photometry, and slit spectroscopy on the L1014 dense core. We detected three Halpha emission line stars. We interpret one as weak-line T Tauri star (WTTS) and the others as classical T Tauri stars (CTTS). Since their g'-i' colors and/or classified spectral types are consistent with those of T Tauri stars and two of them show less extinction than the cloud, these three stars are likely to be T Tauri stars associated with L1014. Adopting an age range for T Tauri stars, 1-10 Myr, the color-magnitude diagram suggests a distance of ~400-900 pc, rather than the previously assumed distance, 200 pc. This could strongly affect on the mass estimate of L1014-IRS, which is thought to be either a very young protostar or proto-brown dwarf.Comment: 5 pages, 5 figures, to be published in Vol.58, No.5, October 25, 200

    Preservation Temperature and Replantation of an Amputated Ear in the Rabbit

    Get PDF
    Using the amputated ear of a rabbit, the influence of the preservation temperature and duration of ischemia of the amputated ear on successful replantation was experimentally studied. Satisfactory replantation was achieved after preservation at a relatively low temperature (4 to 10°C), even after ischemia for as long as 48 hours. At ordinary temperatures (27°C), however, ischemia for 6 hours appeared to be the upper limit for successful replantation

    Early transplantation of mesenchymal stem cells after spinal cord injury relieves pain hypersensitivity through suppression of pain-related signaling cascades and reduced inflammatory cell recruitment

    Get PDF
    Bone marrow-derived mesenchymal stem cells (BMSC) modulate inflammatory/immune responses and promote motor functional recovery after spinal cord injury (SCI). However, the effects of BMSC transplantation on central neuropathic pain and neuronal hyperexcitability after SCI remain elusive. This is of importance because BMSC-based therapies have been proposed for clinical treatment. We investigated the effects of BMSC transplantation on pain hypersensitivity in green fluorescent protein (GFP)-positive bone marrow-chimeric mice subjected to a contusion SCI, and the mechanisms of such effects. BMSC transplantation at day 3 post-SCI improved motor function and relieved SCI-induced hypersensitivities to mechanical and thermal stimulation. The pain improvements were mediated by suppression of protein kinase C-γ and phosphocyclic AMP response element binding protein expression in dorsal horn neurons. BMSC transplants significantly reduced levels of p-p38 mitogen-activated protein kinase and extracellular signal-regulated kinase (p-ERK1/2) in both hematogenous macrophages and resident microglia and significantly reduced the infiltration of CD11b and GFP double-positive hematogenous macrophages without decreasing the CD11b-positive and GFP-negative activated spinal-microglia population. BMSC transplants prevented hematogenous macrophages recruitment by restoration of the blood-spinal cord barrier (BSCB), which was associated with decreased levels of (a) inflammatory cytokines (tumor necrosis factor-α, interleukin-6); (b) mediators of early secondary vascular pathogenesis (matrix metallopeptidase 9); (c) macrophage recruiting factors (CCL2, CCL5, and CXCL10), but increased levels of a microglial stimulating factor (granulocyte-macrophage colony-stimulating factor). These findings support the use of BMSC transplants for SCI treatment. Furthermore, they suggest that BMSC reduce neuropathic pain through a variety of related mechanisms that include neuronal sparing and restoration of the disturbed BSCB, mediated through modulation of the activity of spinal-resident microglia and the activity and recruitment of hematogenous macrophages

    Early Transplantation of Mesenchymal Stem Cells After Spinal Cord Injury Relieves Pain Hypersensitivity Through Suppression of Pain-Related Signaling Cascades and Reduced Inflammatory Cell Recruitment

    Get PDF
    This novel study demonstrated that mesenchymal stem cell transplants after spinal cord injury reduce neuropathic pain, giving details of reduced pain signalling pathways affected. The work is essential in the translation of stem cell therapies for CNS regeneration.Bone marrow-derived mesenchymal stem cells (BMSC) modulate inflammatory/immune responses and promote motor functional recovery after spinal cord injury (SCI). However, the effects of BMSC transplantation on central neuropathic pain and neuronal hyperexcitability after SCI remain elusive. This is of importance because BMSC-based therapies have been proposed for clinical treatment. We investigated the effects of BMSC transplantation on pain hypersensitivity in green fluorescent protein (GFP)-positive bone marrow-chimeric mice subjected to a contusion SCI, and the mechanisms of such effects. BMSC transplantation at day 3 post-SCI improved motor function and relieved SCI-induced hypersensitivities to mechanical and thermal stimulation. The pain improvements were mediated by suppression of protein kinase C-γ and phosphocyclic AMP response element binding protein expression in dorsal horn neurons. BMSC transplants significantly reduced levels of p-p38 mitogen-activated protein kinase and extracellular signal-regulated kinase (p-ERK1/2) in both hematogenous macrophages and resident microglia and significantly reduced the infiltration of CD11b and GFP double-positive hematogenous macrophages without decreasing the CD11b-positive and GFP-negative activated spinal-microglia population. BMSC transplants prevented hematogenous macrophages recruitment by restoration of the blood-spinal cord barrier (BSCB), which was associated with decreased levels of (a) inflammatory cytokines (tumor necrosis factor-α, interleukin-6); (b) mediators of early secondary vascular pathogenesis (matrix metallopeptidase 9); (c) macrophage recruiting factors (CCL2, CCL5, and CXCL10), but increased levels of a microglial stimulating factor (granulocyte-macrophage colony-stimulating factor). These findings support the use of BMSC transplants for SCI treatment. Furthermore, they suggest that BMSC reduce neuropathic pain through a variety of related mechanisms that include neuronal sparing and restoration of the disturbed BSCB, mediated through modulation of the activity of spinal-resident microglia and the activity and recruitment of hematogenous macrophages

    Initiation and progression of ossification of the posterior longitudinal ligament of the cervical spine in the hereditary spinal hyperostotic mouse (twy/twy)

    Get PDF
    Ossification of the posterior longitudinal ligament (OPLL) is a significantly critical pathology that can eventually cause serious myelopathy. Ossification commences in the vertebral posterior longitudinal ligaments, and intensifies and spreads with the progression of the disease, resulting in osseous projections and compression of the spinal cord. However, the paucity of histological studies the underlying mechanisms of calcification and ossification processes remain obscure. The pathological process could be simulated in the ossifying process of the ligament in mutant spinal hyperostotic mouse (twy/twy). The aim of this study is to observe that enlargement of the nucleus pulposus followed by herniation, disruption and regenerative proliferation of annulus fibrosus cartilaginous tissues participated in the initiation of ossification of the posterior longitudinal ligament of twy/twy mice

    Relationship between postprandial glucose level and carotid artery stiffness in patients without diabetes or cardiovascular disease

    Get PDF
    BACKGROUND: The aim of this study was to evaluate the relationship between postprandial glucose level and atherosclerosis in patients without diabetes and cardiovascular disease by determining carotid ultrasonographic variables and serum levels of 1,5-anhydroglucitol (1,5-AG). METHODS: The subjects were 72 patients without diabetes and cardiovascular disease being treated for hypertension or dyslipidemia. The clinical characteristics of all subjects, including the serum level of 1,5-AG, which appears to be well suited for monitoring postprandial hyperglycemia, were evaluated after an overnight fast. The average intima-media thickness (IMT) and the average pulsatility index (PI) of the right and left common carotid arteries were determined with high-resolution ultrasonography and used as ultrasonographic variables. The subjects were divided into a Lower 1,5-AG group (n = 36) and a Higher 1,5-AG group (n = 36). We evaluated the relationship between clinical characteristics and ultrasonographic variables of the carotid artery in both groups. RESULTS: The average PI in the Lower 1,5-AG group was significantly higher than that in the Higher 1,5-AG group, but the average IMT did not differ between the groups. Linear regression analysis, with the ultrasonographic variables as the dependent variables, with 1,5-AG as the independent variable, and adjusted for other clinical characteristics, showed significant correlation between 1,5-AG and the PI but not between 1,5-AG and IMT. CONCLUSION: Our results suggest that postprandial hyperglycemia increases carotid artery stiffness, but not morphological change, in patients without diabetes or cardiovascular disease
    corecore