104 research outputs found

    The relationships between neurons containing dopamine and nitric oxide synthase in the ventral tegmental area.

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    Ventral tegmental area (VTA) is a heterogeneous group of dopaminergic cells which contains interfascicular (IF), parabrachial (PBP) and rostral linear (RLi) nuclei. Neurons of this area are involved in the regulation of motor and motivational aspects of behavior and reveal high neuronal plasticity. Among many various neurotransmitters and neuromodulators, nitric oxide (NO) is localized in this region. In the present study, we investigated morphology and distribution of nitric oxide synthase (NOS)-positive neurons in VTA and their colocalization with dopaminergic neurons. The study was performed on six adult Wistar rats. After perfusional fixation, the brains were cut, immunostained for tyrosine hydroxylase (TH) and NOS and studied by confocal laser microscopy. In each of the three studied nuclei of VTA we investigated three different neuronal populations. Numerous TH-immunoreactive (TH-ir) and NOS-immunoreactive (NOS-ir) neurons are present in the studied region. Among them, a considerable number showed coexistence of both neurotransmitters. The populations of TH-ir and NOS-ir neurons interact with each other as manifested by the presence of NOS-ir endings on TH-ir neurons and vice versa. Taking the above into account, it may be suspected that NO is involved in the modulation of dopaminergic transmission

    Fluoride alters type I collagen expression in the early stages of odontogenesis

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    Fluoride alters the expression and post-translational modifications of extracellular matrix proteins in dentin. The aim of our study was to determine the effects of fluoride on type I collagen expression during the early stages of tooth germ development in rats. Pregnant dams were divided into three groups and fed a standard diet. From the fifth day of pregnancy the three groups received tap water with, respectively, trace amounts of fluoride (C), a low fluoride concentration (FL) or and a high fluoride concentration (FH). Changes in type I collagen expression and distribution were evaluated. The expression of type I collagen was restricted to the extracellular spaces of cells of mesenchymal origin. In the youngest animals the most intense immunoreactivity for type I collagen was detected in predentin of the FL group. Although the intensity of immunostaining increased in proportion to the age of the animals, the largest increase in the groups investigated was detected in the FL group. We concluded that a low concentration of fluoride can act as a stimulator of type I collagen deposition in the extracellular matrix of dentin, while high concentrations of fluoride have an opposite effect, acting as an inhibitor of type I collagen formation in dentin

    Changes in NGF/c-Fos colocalization in specific limbic structures of juvenile and aged rats after open field stimulation

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    Changes in NGF release during stressful events have been associated with the activation of neurons expressing NGF receptors. This study examined the influence of acute stress-induced stimulation on NGF/c-Fos colocalization in the following limbic regions: the paraventricular (PV) nucleus of the hypothalamus, medial (MeA) nucleus of the amygdala, and CA3 hippocampus. Juvenile (P21) and aged rats (P360) were exposed to a 15-minute acute open field (OF) test. Double immunofluorescence staining, used to detect NGF-ir and c-Fos-ir cells, revealed a higher percentage of NGF/c-Fos-ir neurons in the P21 control group than in the P360 control group. Under OF acute stimulation, a statistically significant (p < 0.05) increase of NGF/c-Fos level in CA3 of juvenile animals and in PV and CA3 of the aged rats was observed. These observations indicate that the investigated structures in both age groups show a different response to acute OF stimulation. Acute OF affects the levels of NGF/c-Fos more significantly in aged rats

    THREE-DIMENSIONAL PHOTOGRAPHY AS A NEW TECHNIQUE TO MAKE DIDACTIC PRESENTATIONS MORE ATTRACTIVE

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    In the 21st century, the form of presenting information plays an incredibly important role in arousing interest in research problems. Stereoscopy is among the imaging techniques that have evoked much interest in the recent years. Its numerous applications that can be observed in various fields (such as medicine, space science, law, marketing, or entertainment industry) suggest that we should also use this technology for didactic purposes. The aim of the article is to discuss the process of creating three-dimensional photography and the opportunities offered by stereoscopy, which makes it possible to obtain images with depth effect and impression of solidity. The authors describe different ways to obtain three-dimensional images and the devices applied in the process, as well as techniques of presenting three-dimensional material to a wider audience. The methods of free-viewing (the oldest method of viewing stereoscopic images), anaglyph (a simple method applied in printing and displaying static images and movies on screen), lenticular raster (employing a series of narrow vertical cylindrical lenses), and stereoscopy (in which mirrors, lenses, prisms, or filters are used) are discussed. Also, the application of computer technology is reviewed and the ways in which stereoscopy can benefit from this medium owing to the use of LCD shutter glasses. Contemporary technology offers considerable opportunities, at the same time posing ever-increasing demands, which are mentioned in the paper, too. Teaching is most effective when information is received through multiple channels, combining verbal and visual messages. Owing to 3D images, the recipients grasp more information details, remember them longer, and are more interested in the message content. Creating didactic presentations with the use of three-dimensional photographs or films is presented as a way of arousing interest, allowing direct participation in the cognitive process, and facilitating the reception of the transmitted content

    The relationships between neurons containing dopamine and nitric oxide synthase in the ventral tegmental area.

    Get PDF
    Ventral tegmental area (VTA) is a heterogeneous group of dopaminergic cells which contains interfascicular (IF), parabrachial (PBP) and rostral linear (RLi) nuclei. Neurons of this area are involved in the regulation of motor and motivational aspects of behavior and reveal high neuronal plasticity. Among many various neurotransmitters and neuromodulators, nitric oxide (NO) is localized in this region. In the present study, we investigated morphology and distribution of nitric oxide synthase (NOS)-positive neurons in VTA and their colocalization with dopaminergic neurons. The study was performed on six adult Wistar rats. After perfusional fixation, the brains were cut, immunostained for tyrosine hydroxylase (TH) and NOS and studied by confocal laser microscopy. In each of the three studied nuclei of VTA we investigated three different neuronal populations. Numerous TH-immunoreactive (TH-ir) and NOS-immunoreactive (NOS-ir) neurons are present in the studied region. Among them, a considerable number showed coexistence of both neurotransmitters. The populations of TH-ir and NOS-ir neurons interact with each other as manifested by the presence of NOS-ir endings on TH-ir neurons and vice versa. Taking the above into account, it may be suspected that NO is involved in the modulation of dopaminergic transmission

    Enzymatic Characterization of ER Stress-Dependent Kinase, PERK, and Development of a High-Throughput Assay for Identification of PERK Inhibitors

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    PERK is serine/threonine kinase localized to the endoplasmic reticulum (ER) membrane. PERK is activated and contributes to cell survival in response to a variety of physiological stresses that affect protein quality control in the ER, such as hypoxia, glucose depravation, increased lipid biosynthesis, and increased protein translation. Pro-survival functions of PERK are triggered by such stresses, suggesting that development of small-molecule inhibitors of PERK may be efficacious in a variety of disease scenarios. Hence, we have conducted a detailed enzymatic characterization of the PERK kinase to develop a high-throughput-screening assay (HTS) that will permit the identification of small-molecule PERK inhibitors. In addition to establishing the Km of PERK for both its primary substrate, eIF2?, and for adenosine triphosphate, further mechanistic studies revealed that PERK targets its substrate via either a random/steady-state ordered mechanism. For HTS, we developed a time-resolved fluorescence resonance energy transfer–based assay that yielded a robust Z? factor and percent coefficient of variation value, enabling the successful screening of 79,552 compounds. This approach yielded one compound that exhibited good in vitro and cellular activity. These results demonstrate the validity of this screen and represent starting points for drug discovery efforts

    Increasing of train movement energy efficiency on a service area

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    Energy efficiency is one of the most important factors affecting the increase of the railway transport competitiveness on transport services market. Analysis showed that the main energy consumption is connected with traction of trains. To decrease the influence of this expenses item automated system «ELBRUS» that allows developing energy saving train schedules was used within the research. As a result, an optimal energy saving train schedule that improves quantitative and qualitative indexes of a service area was determined.Энергоэффективность является одним из основных факторов, влияющих на повышение конкурентоспособности железнодорожного транспорта на рынке транспортных услуг. Анализ показал, что основной расход топливно-энергетических ресурсов приходится на тягу поездов. С целью снижения данной статьи расходов в рамках исследования применен АПК «ЭЛЬБРУС», позволяющий разрабатывать вариантные энергосберегающие графики движения поездов. В результате, определен энергооптимальный вариант организации движения поездов, улучшающий количественные и качественные показатели работы участка

    The LAGUNA design study- towards giant liquid based underground detectors for neutrino physics and astrophysics and proton decay searches

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    The feasibility of a next generation neutrino observatory in Europe is being considered within the LAGUNA design study. To accommodate giant neutrino detectors and shield them from cosmic rays, a new very large underground infrastructure is required. Seven potential candidate sites in different parts of Europe and at several distances from CERN are being studied: Boulby (UK), Canfranc (Spain), Fr\'ejus (France/Italy), Pyh\"asalmi (Finland), Polkowice-Sieroszowice (Poland), Slanic (Romania) and Umbria (Italy). The design study aims at the comprehensive and coordinated technical assessment of each site, at a coherent cost estimation, and at a prioritization of the sites within the summer 2010.Comment: 5 pages, contribution to the Workshop "European Strategy for Future Neutrino Physics", CERN, Oct. 200

    Symmetry protection of measurement-based quantum computation in ground states

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    The two-dimensional cluster state, a universal resource for measurement-based quantum computation, is also the gapped ground state of a short-ranged Hamiltonian. Here, we examine the effect of perturbations to this Hamiltonian. We prove that, provided the perturbation is sufficiently small and respects a certain symmetry, the perturbed ground state remains a universal resource. We do this by characterising the operation of an adaptive measurement protocol throughout a suitable symmetry-protected quantum phase, relying on generic properties of the phase rather than any analytic control over the ground state.Comment: 20 pages plus appendices, 11 figures, comments very welcome; v2 minor corrections and additional references; v3 published version with minor correction
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