65 resultados para imuno-fluorescência direta


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In this study, two circadian related centres, the suprachiasmatic nucleus (SCN) and the intergeniculate leaflet (IGL) were evaluated in respect to their cytoarchitecture, retinal afferents and chemical content of major cells and axon terminals with a tract tracer and immunohistochemical techniques in the rock cavy (Kerodon rupestris), a Brazilian caviidae rodent species. The rock cavy SCN is innervated in its ventral portion by terminals from the predominantly contralateral retina. It also contains neurophisin and vasoactive intestinal polypeptide immunoreactive cell bodies and neuropeptide Y and enkephalin immunopositive fibres and terminals and is marked by intense GFAP immunoreactivity. The IGL receives a predominantly contralateral retinal projection, contains neuropeptide Y and nitric oxide synthase producing neurons and enkephalin immunopositive terminals and is characterized by dense GFAP immunoreactivity. This is the first report examining the neural circadian system in a crepuscular rodent species for which circadian properties have been described. The results are discussed comparing with what has been described for other species and in the context of the functional significance of these centres

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The light, besides the vision stimuli, controls other process completely independent of image formation, such as the synchronization of the organismic circadian rhythms to the enviromental light/dark cycle. In mammals, this adjust occurs through the retinohypothalamic tract, a direct retinal projection to the suprachiasmatic nucleus, considered to be the major circadian pacemaker. Early studies have identified only the suprachiasmatic nucleus as a retinal target in the hypothalamus. However, using more sensitive neuroanatomic tracers, other retinorecipient hypothalamic regions outside to suprachiasmatic nucleus were pointed in a great number of mammalian species. In this study, the retinohypothalamic tract was shown in the rock cavy (Kerodon rupestris), an endemic rodent of the semiarid region of the Brazilian Northeast, using unilateral intravitreal injections of cholera toxin subunit b as a neuronal tracer. The results reveal that in the rock cavy, besides the suprachiasmatic nucleus, several hypothalamic regions receive direct retinal projection, such as the ventrolateral preoptic nucleus, medial and lateral preoptic areas, the supraoptic nucleus and bordering areas, anterior, lateral and rectrochiasmatic hypothalamic areas, and the subparaventricular zone. The results are discussed by comparing with those of the literature, into a functional context

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The quantitative chemical characterization of the inorganic fraction of scale products is very relevant in studying, monitoring and controlling corrosive processes of oil pipelines. The X-ray fluorescence spectrometry (XRF) is a very versatile analytical technique, which can be used in quantitative analysis in solid samples at low concentrations of the chemical element, in the order of few ppm. A methodology that involves sample preparation diluted in the proportion of 1:7 (one portion of the sample for seven of wax), pressed as pellets was used in the XRF calibration for chemical analysis of scale products from oil pipelines. The calibration involved the preparation of reference samples from mixtures of P.A. reagents, aiming to optimize the time consumed in the steps of sample preparation and analysis of Al, Ba, Ca, Fe, K, Mg, Mn, Na, P, S, Si, Sr and Ti, using the same pressed pellet for trace and major elements analysis

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The proposal of this work is to evaluate the influence of the organic matter on the results of the analyses of the metals (Zn, Pb, Al, Cu, Cr, Fe, Cd e Ni) for Atomic Absorption Spectrometry (AAS), so much in the extraction stage as in the reading using for that the chemometrics. They were used for this study sample of bottom sediment collected in river Jundiaí in the vicinity of the city of Macaíba-RN, commercial humus and water of the station of treatment of sewer of UFRN. Through the analyses accomplished by EAA it was verified that the interference of the organic matter happens in the extraction stage and not in the reading. With relationship to the technique of X Ray Fluorescence Spectrometry (XRFS), the present work has as intended to evaluate the viability of this technique for quantitative analysis of trace metals (Cr, Ni, Cu, Zn, Rb, Sr and Pb) in having leached obtained starting from the extraction with acqua regia for an aqueous solution. The used samples constitute the fine fraction (<0.063 mm) of sediments of swamp of the river Jundiaí. The preparation of tablets pressed starting from the dry residue of those leached it allowed your analysis in the solid form. This preliminary study shows that, in the case of the digestion chemistry partially of the fine fractions of bottom sediments used for environmental studies, the technique of applied EFRX to the analysis of dry residues starting from having leached with acqua regia, compared her it analyzes of the leached with ICP-OES, it presents relative mistakes for Cu, Pb, Sr and Zn below 10%

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This study aid to understand the work conditions of street vendors located on the sidewalks of two malls in Brazil Northeast Natal / RN - Both malls Natal Shopping and Via Direta, to analyze their inclusion in the informal economy and to study the supposed autonomy provided by work as self-employment in its both aspects economic and social analyzing the importance on the condition of "masters of their own business" has for the street vendors, as an alternative to not submission to the figure of the boss, that represents the exploitation of one class over another. The theoretical and methodological aspects that support this study was aimed in discussion on the restructuring of production, considering its effects on the world of work, pointing to unemployment as one of the potencies element of excluded processes that exciting workers to engage in the informal market. Informality is presented as a survival strategy and as integrating part of the reproduction of capital. This research was conducted under a critical perspective, whish has been utilized quantitative and qualitative analyses. The results of this study format questions that provided during the research process the socio-economic characterization of workers, main cause of this study, and how street vendors expres their status of workers as self-employed for their work, and the perception that they have on their form of inclusion in the informal market.

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Due to the constantly increasing use of wireless networks in domestic, business and industrial environments, new challenges have emerged. The prototyping of new protocols in these environments is typically restricted to simulation environments, where there is the need of double implementation, one in the simulation environment where an initial proof of concept is performed and the other one in a real environment. Also, if real environments are used, it is not trivial to create a testbed for high density wireless networks given the need to use various real equipment as well as attenuators and power reducers to try to reduce the physical space required to create these laboratories. In this context, LVWNet (Linux Virtual Wireless Network) project was originally designed to create completely virtual testbeds for IEEE 802.11 networks on the Linux operating system. This paper aims to extend the current project LVWNet, adding to it the features like the ability to interact with real wireless hardware, provides a initial mobility ability using the positioning of the nodes in a space coordinates environment based on meters, with loss calculations due to attenuation in free space, enables some scalability increase by creating an own protocol that allows the communication between nodes without an intermediate host and dynamic registration of nodes, allowing new nodes to be inserted into in already in operation network

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The activation of hepatic stellate cells (HSC) is considered the most important event in hepatic fibrogenesis. The precise mechanism of this process is unknown in autoimmune hepatitis (AIH), and more evidence is needed on the evolution of fibrosis. The aim of this study was to assess these aspects in children with type 1 AIH. We analyzed 16 liver biopsy samples from eight patients, paired before treatment and after clinical remission, performed an immunohistochemical study with anti-actin smooth muscle antibody and graded fibrosisand inflammation on a scale of 0:4 (Batts and Ludwig scoring system). We observedthere was no significant reduction in fibrosis scores after 24± 18 months (2.5 ± 0.93 vs. 2.0± 0.53, P = 0.2012). There was an important decrease in inflammation: portal (2.6 ±0.74 vs. 1.3± 0.89, P = 0.0277), periportal/periseptal (3.0 ±0.76 vs. 1.4 ± 1.06, P = 0.0277), and lobular (2.8 ± 1.04 vs. 0.9± 0.99, P =0.0179). Anti-actin smooth muscle antibodies were expressed in the HSC of the initial biopsies (3491.93 ±2051.48 lm2), showing a significant reduction after remission (377.91 ±439.47 lm2) (P = 0.0117). HSC activation was demonstrated in the AIH of children. The reduction of this activation after clinical remission, which may precede a decrease in fibrosis, opens important perspectives in the follow-up of AIH.

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Periodontal disease is an inflammatory condition of infectious nature characterized by destruction of protecting and supporting dental tissues. It happens as a response produced by the host when attacked by microorganisms. Several factors are involved in this process. Among them, cytokines are key regulatory molecules in this immune response, playing a role either protective and/or destructive in lesion progression. Thus, this study investigated the immunohistochemical expression of IFN- , GATA-3, IL-17, IL-23, IL-6 and TGF- in gingival tissues of humans, in an attempt to gain a better understanding of the participation of Th1, Th2 and Th17 immune responses in the development of periodontal disease processes. To this end, eighty-two samples of gingival tissues were divided into three groups: Group 1 = 15 (samples of healthy gum tissue as controls), Group 2 = 36 (samples with chronic gingivitis) and Group 3 = 31 (samples with chronic periodontitis). All cases were submitted to morphological analysis from sections stained with hematoxylin and eosin and then subjected to staining by immunohistochemistry using the streptavidin-biotin method. Results showed positive labeling for all proteins. Nonetheless, we observed a greater expression of Th1 cytokines and Th17 cells in group 3. We found statistically significant difference between TGF- expression and the clinical condition of the samples (p=0.02). We conclude that Th1 and Th17 responses may act synergistically in the destructive process of periodontal tissue, overlapping the Th2 response that was also present in these tissues

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Myofibroblasts are cells that exhibit a hybrid phenotype, sharing the morphological characteristics of fibroblasts and smooth muscle cells, which is acquired during a process called differentiation. These cells then start to express -SMA, a marker that can be used for their identification. Studies suggest that myofibroblasts are related to the aggressiveness of different tumors and that TGF-1 and IFN- play a role in myofibroblast differentiation, stimulating or inhibiting this differentiation, respectively. The objective of this study was to investigate the role of myofibroblasts in epithelial odontogenic tumors, correlating the presence of these cells with the aggressiveness of the tumor. Immunohistochemistry was used to evaluate the expression of TGF-1 and IFN- in myofibroblast differentiation, as well as the expression of MMP-13, which is activated by myofibroblasts, and of EMMPRIN (extracellular matrix metalloproteinase inducer) as a precursor of this MMP. The sample consisted of 20 solid ameloblastomas, 10 unicystic ameloblastomas, 20 odontogenic keratocysts, and 20 adenomatoid odontogenic tumors. For evaluation of myofibroblasts, anti- -SMA-immunoreactive cells were quantified in connective tissue close to the epithelium. Immunoexpression of TGF-1, IFN-, MMP-13 and EMMPRIN was evaluated in the epithelial and connective tissue components, attributing scores of 0 to 4. The results showed a higher concentration of myofibroblasts in solid ameloblastomas (mean of 30.55), followed by odontogenic keratocysts (22.50), unicystic ameloblastomas (20.80), and adenomatoid odontogenic tumors (19.15) (p=0.001). No significant correlation between TGF-1 and IFN- was observed during the process of myofibroblast differentiation. There was also no correlation between the quantity of myofibroblasts and MMP-13 expression. Significant correlations were found between MMP-13 and TGF-1 (r=0.087; p=0.011), between MMP- 13 and IFN- (r=0.348; p=0.003), as well as between EMMPRIN and MMP-13 (r=0.474; p<0.001) and between EMMPRIN and IFN- (r=0.393; p=0.001). The higher quantity of myofibroblasts observed in solid ameloblastomas, odontogenic keratocysts and unicystic ameloblastomas suggests that these cells are one of the factors responsible for the more aggressive biological behavior of these tumors, although the myofibroblast population was not correlated with TGF-1, IFN-, MMP-13 or EMMPRIN. The correlation between MMP- 13 and TGF-1 suggests that the latter induces the expression of this metalloproteinase. The present results also support the well-established role of EMMPRIN as an inducer of MMP-13. Furthermore, the relationship between EMMPRIN and IFN- and between MMP-13 and IFN- suggests synergism in the antifibrotic effect of these markers

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The Baixa grande fault is located on the edge of the S-SW Potiguar Rift. It limits the south part of Umbuzeiro Graben and the Apodi Graben. Although a number of studies have associated the complex deformation styles in the hanging wall of the Baixa Grande Fault with geometry and displacement variations, none have applied the modern computational techniques such as geometrical and kinematic validations to address this problem. This work proposes a geometric analysis of the Baixa Fault using seismic interpretation. The interpretation was made on 3D seismic data of the Baixa Grande fault using the software OpendTect (dGB Earth Sciences). It was also used direct structural modeling, such as Analog Direct Modeling know as Folding Vectors and, 2D and 3D Direct Computational Modeling. The Folding Vectors Modeling presented great similarity with the conventional structural seismic interpretations of the Baixa Grande Fault, thus, the conventional interpretation was validated geometrically. The 2D direct computational modeling was made on some sections of the 3D data of the Baixa Grande Fault on software Move (Midland Valley Ltd) using the horizon modeling tool. The modeling confirms the influence of fault geometry on the hanging wall. The Baixa Grande Fault ramp-flat-ramp geometry generates synform on the concave segments of the fault and antiform in the convex segments. On the fault region that does not have segments angle change, the beds are dislocated without deformation, and on the listric faults occur rollover. On the direct 3D computational modeling, structural attributes were obtained as horizons on the hanging wall of the main fault, after the simulation of several levels of deformation along the fault. The occurrence of structures that indicates shortening in this modeling, also indicates that the antiforms on the Baixa Grande Fault were influenced by fault geometry

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The RANK / RANKL / OPG sy stem plays an important role in bone formation and resorption . This finding has been regarded as one of the m ost important advances in the understanding of bone biology with respect to osteoclastogenesis. The aim of this study was to investigate the expression of RANKL / RANK / OPG markers in reimplanted t eeth of rats, and to observe the relationship between the expression of these markers and to oth and bone resorption. Thirty male Wistar rats (Rattus norvegicus albinos) had their maxillary right incisors extrac ted , and were divided into 2 groups according to the period that the extracted teeth were kept in dry air before reimplantation : G1 (n = 15) - 5 minutes , and G2 (n = 15) - 60 minutes . After reimplantation, teeth were analyzed at intervals of 1, 3 and 7 da ys. After these experimental periods, the animals were euthanized. Longitudinal sections with 5μm thick were obtained and stained with Hematoxylin and Eosin for histological analysis , while 3μm thick sections were subjected to immunohistochemical analysis of OPG , RANK and RANKL. The results showed that the RANK / RANKL / OPG system actively participates in both the repair process, as well as tooth and bone resorption . Extr a - alveolar time of 60 minutes before replantation caused minor expressions of RANKL a nd OPG, not influencing the expression of RANK; RANKL immunostaining showed higher in both groups when compared to other biomarkers, participating in all phases of bone and tooth resorption; RANKL was associated to both osteoclastogenesis and c ell ular proliferation , and was expressed in both groups.

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The water supply and treatment is considered as a great benefit considering that, if done efficiently, provides public health. However, considering the WTP (Water Treatment Plant) is an industry, with its inputs and waste generation, they must be constantly evaluated and monitored to verify the best and most appropriate way to process and dispose their waste, minimizing therefore the potential impacts to the environment. By volume, the most significant waste is the rapid filter backwash water. It is very common the disposal of this waste without treatment in water sources, which are used, for the most part, as a water supply source of a downstream population. This study evaluated quantitative and qualitative parameters in filter backwash water in three WTP - Itaitinga, Maranguape and Pacatuba, located in Ceará State, northeast of Brazil. It was found that the Maranguape WTP, in terms of treatment capacity, is the larger. The Itaitinga WTP is the one that consumes more water during filters washing. The Pacatuba WTP exhibited higher concentration of total suspended and settleable solids, COD and aluminum in the filters backwash water. It is noteworthy that the settleable solids and total suspended solids in all three WTP are above the effluent discharge standard recommended by Resolution 154/2002 of SEMACE (State Superintendent of Environment of Ceará). It was concluded that the filter backwash water from the study WTP exceeded the allowed values for legislation to be disposed directly into surface water bodies. It is suggested as an alternative to treat and recycle the filter backwashing water the construction of sludge settling ponds.

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The development and progression of odontogenic tumors have been associated with an imbalance in the activity of growth factors, adhesion molecules, extracellular matrix proteins and their degradation enzymes, angiogenic factors and osteolytic. Some studies have shown that interaction relationships inductive epithelial / mesenchymal determinants of Odontogenesis are mimicked by these tumors. The objective of this research was to investigate the immunolocalization of growth factors (BMP-4 and FGF-8) and Sindecan-1 structural protein in a series of odontogenic tumors presenting different biological behaviors, to contribute to a better understanding of the role of these proteins in tumor development. The sample consisted of 21 of the solid ameloblastoma, odontogenic keratocysts 19 and 14 odontogenic adenomatoid tumors. Increased Sindecan-1 immunostaining was seen in the epithelium of the lesions when compared with mesenchyme. In ameloblastoma and odontogenic keratocysts, this expression was higher than in AOT. Epithelial expression of BMP4 showed quantitatively similar in the three studied lesions; however, when anlisada mesenchymal immunoreactivity, was detected significant higher expression when compared to the ameloblastoma keratocysts. In ameloblastoma, mesenchymal expression was predominantly (p = 0.008), while in keratocyst higher expression in the epithelium was observed (p = 0.046). In all injuries, strong or moderate correlation was observed in the BMP-4 immunoreactivity in the epithelium and mesenchyme. FGF-8, no injury was observed difference between the immunoreactivity in the epithelium or mesenchyme, however in ameloblastoma positive correlation was found (Spearman correlation, rho = 0.857, p <0.001). The results of this study suggest that the three evaluated biomarkers actively involved in the pathogenesis of lesions, especially the expression of ameloblastomas indicating a strong interaction between parenchymal and stromal cells which may contribute to its marked aggressiveness.

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Periodontal disease is a chronic inflammatory condition primarily caused by bacteria in dental biofilm, which interact with the host, thus determining the nature of the resulting disease. Despite the wide knowledge about the pathogenesis of these diseases, the exact composition of the T cell profile during the active phase of the disease (Th1, Th2 or Th17) remains unknown. This study aimed to evaluate by immunohistochemical expression, the presence of the markers (IL-17, IL-23 and RORγt), involved in Th17 response in clinically healthy gingiva cases (n = 32), biofilm-induced gingivitis (n = 30), chronic periodontitis (n = 32) and aggressive periodontitis (n = 25), in order to analyze if the expression and/or distribution of these molecules in lymphocytes and macrophages, present in the inflammatory infiltrate of periodontal tissue, influences the tissue destruction observed in these diseases. The morphological analysis of cases was performed which assessed the intensity of the inflammatory infiltrate in mild, moderate and intense. For each case, in the area with the most representative immunostaining, 5 fields were chosen and analyzed, both for the intensity of the inflammatory infiltrate as for the quantity of immunostained cells, based on predetermined scores: score 0 (absence of inflammatory infiltrate/immunostaining), score 1 (the infiltrate/immunostaining covered less than 25% of the field area), score 2 (the infiltrate/immunostaining occupied between 25 and 50%) and score 3 (infiltrate/immunostaining present in over 50% of the field area). From this, a median was generated representing each case. The intensity of the inflammatory infiltrate correlated with the disease progression, in other words, it was crescent from clinically healthy gingiva to aggressive periodontitis (P <0.001). It was detected the presence of IL-17, IL-23 and RORγt in most of the evaluated cases and the number of immunostained cells correlated with the intensity of the inflammatory infiltrate (P <0.001) and with the clinical parameters analyzed (P <0.001), showing a positive correlation, mainly moderate. Aggressive periodontitis showed a higher percentage of immunostaining for all markers in relation to other clinical conditions assessed, suggesting a possible association of these markers with the progression of this disease, in which the higher the loss of periodontal support, the greater the amount of inflammatory infiltrate and larger the number of immunostained cells.

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The fluorescent proteins are an essential tool in many fields of biology, since they allow us to watch the development of structures and dynamic processes of cells in living tissue, with the aid of fluorescence microscopy. Optogenectics is another technique that is currently widely used in Neuroscience. In general, this technique allows to activate/deactivate neurons with the radiation of certain wavelengths on the cells that have ion channels sensitive to light, at the same time that can be used with fluorescent proteins. This dissertation has two main objectives. Initially, we study the interaction of light radiation and mice brain tissue to be applied in optogenetic experiments. In this step, we model absorption and scattering effects using mice brain tissue characteristics and Kubelka-Munk theory, for specific wavelengths, as a function of light penetration depth (distance) within the tissue. Furthermore, we model temperature variations using the finite element method to solve Pennes’ bioheat equation, with the aid of COMSOL Multiphysics Modeling Software 4.4, where we simulate protocols of light stimulation tipically used in optogenetics. Subsequently, we develop some computational algorithms to reduce the exposure of neuron cells to the light radiation necessary for the visualization of their emitted fluorescence. At this stage, we describe the image processing techniques developed to be used in fluorescence microscopy to reduce the exposure of the brain samples to continuous light, which is responsible for fluorochrome excitation. The developed techniques are able to track, in real time, a region of interest (ROI) and replace the fluorescence emitted by the cells by a virtual mask, as a result of the overlay of the tracked ROI and the fluorescence information previously stored, preserving cell location, independently of the time exposure to fluorescent light. In summary, this dissertation intends to investigate and describe the effects of light radiation in brain tissue, within the context of Optogenetics, in addition to providing a computational tool to be used in fluorescence microscopy experiments to reduce image bleaching and photodamage due to the intense exposure of fluorescent cells to light radiation.