33 research outputs found
Laminar-specific distribution of zinc: Evidence for presence of layer IV in forelimb motor cortex in the rat
ยฉ 2014 Elsevier Inc.The rat is the most widely studied pre-clinical model system of various neurological and neurodegenerative disorders affecting hand function. Although brain injury to the forelimb region of the motor cortex in rats mostly induces behavioral abnormalities in motor control of hand movements, behavioral deficits in the sensory-motor domain are also observed. This questions the prevailing view that cortical layer IV, a recipient of sensory information from the thalamus, is absent in rat motor cortex. Because zinc-containing neurons are generally not found in pathways that run from the thalamus, an absence of zinc (Zn) in a cortical layer would be suggestive of sensory input from the thalamus. To test this hypothesis, we used synchrotron micro X-ray fluorescence imaging to measure Zn distribution across cortical layers. Zn maps revealed a heterogeneous layered Zn distribution in primary and secondary motor cortices of the forelimb region in the adult rat. Two wider bands with elevated Zn content were separated by a narrow band having reduced Zn content, and this was evident in two rat strains. The Zn distribution pattern was comparable to that in sensorimotor cortex, which is known to contain a well demarcated layer IV. Juxtaposition of Zn maps and the images of brain stained for Nissl bodies revealed a "Zn valley" in primary motor cortex, apparently starting at the ventral border of pyramidal layer III and ending at the close vicinity of layer V. This finding indicates the presence of a conspicuous cortical layer between layers III and V, i.e. layer IV, the presence of which previously has been disputed. The results have implications for the use of rat models to investigate human brain function and neuropathology, such as after stroke. The presence of layer IV in the forelimb region of the motor cortex suggests that therapeutic interventions used in rat models of motor cortex injury should target functional abnormalities in both motor and sensory domains. The finding is also critical for future investigation of the biochemical mechanisms through which therapeutic interventions can enhance neural plasticity, particularly through Zn dependent pathways
Parallel changes in cortical neuron biochemistry and motor function in protein-energy malnourished adult rats
While protein-energy malnutrition in the adult has been reported to induce motor abnormalities and exaggerate motor deficits caused by stroke, it is not known if alterations in mature cortical neurons contribute to the functional deficits. Therefore, we explored if PEM in adult rats provoked changes in the biochemical profile of neurons in the forelimb and hindlimb regions of the motor cortex. Fourier transform infrared spectroscopic imaging using a synchrotron generated light source revealed for the first time altered lipid composition in neurons and subcellular domains (cytosol and nuclei) in a cortical layer and region-specific manner. This change measured by the area under the curve of the d(CH2) band may indicate modifications in membrane fluidity. These PEM-induced biochemical changes were associated with the development of abnormalities in forelimb use and posture. The findings of this study provide a mechanism by which PEM, if not treated, could exacerbate the course of various neurological disorders and diminish treatment efficacy
ะะธะฝะฐะผะธะบะฐ ะธะทะผะตะฝะตะฝะธั ะผะธะฝะธะผะฐะปัะฝัั ััะพะฒะฝะตะน ะธ ัะฐัั ะพะดะพะฒ ะฝะฐ ัะตะบะต ะัะบะฒะฐัะธ (ะะธะฝะฐะดะทะต).
แแแงแแแแแแแ แแ แ แแแแแแแแ แแแแแแ แ แขแแกแแแ แแ แแแแแแ แ แแขแแแแ แแ แแแแแแแแฃแ แ แแแแแแแแก แชแแแแแแแแแแแก แจแแกแแฎแแ, แกแแแแช แแแแแแ แแแแฃแแ แแแแแชแแแแแ แแ แแแ แแแแแ แแแแแแ. แแ แแแแแ แแแแแแ แแแแแแ แ แแขแแแแ แแ แ แแแแ แช แฉแแแก แแแ แฆแแแฃแแแ แแแฅแกแแแแแฃแ แ แฎแแ แฏแแก (1110 แ/แฌแ) แแแแแแก แแแแ, แ แแแแช แแแแแแฌแแแ แแแแแแแขแแก แแแคแแ แแแชแแ, แแแแขแแ แขแ แแแแแก แจแแคแแกแแแแกแแก (แแแแแแแแฃแ แ แแแแแแแแก แจแแแแฎแแแแแจแ) แแฃแชแแแแแแแแ แแ แแชแแกแแก แแฅแกแขแ แแแแแฃแ แจแแแแฎแแแแแแ แแ แแแแ แจแแแแแแแแก แแแขแแแฃแ แ แแแแแแแ แแแแกแแฎแแแแแแ แ แแแแก แแ แแแแแ แแแแแแแก แจแแคแแกแแแแ แแ แแแแ แแแ แฆแแแแแก แแแแแแแแแก แแแแแแแแแแ.Two examples are given on the change in the minimum levels on the Tisa and Mtkvari rivers, where the observation data are heterogeneous. The homogeneity on the Mtkvari River is evidently violated as a result of passing the maximum flow rate (1110 m3 / s), which caused the bed deformation, therefore, when assessing the trend (in the case of the minimum levels), a detailed analysis of the extreme cases of the process and their results is required with an assessment of homogeneity of the considered line and reasons of their violationะัะธะฒะตะดะตะฝั ะดะฒะฐ ะฟัะธะผะตัะฐ ะพะฑ ะธะทะผะตะฝะตะฝะธะธ ะผะธะฝะธะผะฐะปัะฝะพะณะพ ััะพะฒะฝั ะฝะฐ ัะตะบะฐั
ะขะธัะฐ ะธ ะขะบะฒะฐัะธ, ะณะดะต ะดะฐะฝะฝัะต ะฝะฐะฑะปัะดะตะฝะธั ะฝะตะพะดะฝะพัะพะดะฝั. ะะดะฝะพัะพะดะฝะพััั ะฝะฐ ัะตะบะต ะัะบะฒะฐัะธ, ะบะฐะบ ะฒะธะดะฝะพ, ะฝะฐัััะตะฝะฐ ะฒ ัะตะทัะปััะฐัะต ะฟัะพั
ะพะถะดะตะฝะธั ะผะฐะบัะธะผะฐะปัะฝะพะณะพ ัะฐัั
ะพะดะฐ (1110 ะผ3/ัะตะบ.), ััะพ ะฒัะทะฒะฐะปะพ ะดะตัะพัะผะฐัะธั ัััะปะฐ, ะฟะพััะพะผั ะฟัะธ ะพัะตะฝะบะต ััะตะฝะดะฐ (ะฒ ัะปััะฐะต ะผะธะฝะธะผะฐะปัะฝะพะณะพ ััะพะฒะฝั) ะพะฑัะทะฐัะตะปะตะฝ ะดะตัะฐะปัะฝัะน ะฐะฝะฐะปะธะท ัะบัััะตะผะฐะปัะฝัั
ัะปััะฐะตะฒ ะฟัะพัะตััะฐ ะธ ะธั
ัะตะทัะปััะฐัะพะฒ ั ะพัะตะฝะบะพะน ะพะดะฝะพัะพะดะฝะพััะธ ัะฐััะผะฐััะธะฒะฐะตะผะพะณะพ ััะดะฐ ะธ ะฟัะธัะธะฝ ะฝะฐัััะตะฝะธั
Protein-Energy Malnutrition Exacerbates Stroke-Induced Forelimb Abnormalities and Dampens Neuroinflammation
Protein-energy malnutrition (PEM) pre-existing at stroke onset is believed to worsen functional outcome, yet the underlying mechanisms are not fully understood. Since brain inflammation is an important modulator of neurological recovery after stroke, we explored the impact of PEM on neuroinflammation in the acute period in relation to stroke-initiated sensori-motor abnormalities. Adult rats were fed a low-protein (LP) or normal protein (NP) diet for 28 days before inducing photothrombotic stroke (St) in the forelimb region of the motor cortex or sham surgery; the diets continued for 3 days after the stroke. Protein-energy status was assessed by a combination of body weight, food intake, serum acute phase proteins and corticosterone, and liver lipid content. Deficits in motor function were evaluated in the horizontal ladder walking and cylinder tasks at 3 days after stroke. The glial response and brain elemental signature were investigated by immunohistochemistry and micro-X-ray fluorescence imaging, respectively. The LP-fed rats reduced food intake, resulting in PEM. Pre-existing PEM augmented stroke-induced abnormalities in forelimb placement accuracy on the ladder; LP-St rats made more errors (29 ยฑ 8%) than the NP-St rats (15 ยฑ 3%; P < 0.05). This was accompanied by attenuated astrogliosis in the peri-infarct area by 18% and reduced microglia activation by up to 41 and 21% in the peri-infarct area and the infarct rim, respectively (P < 0.05). The LP diet altered the cortical Zn, Ca, and Cl signatures (P < 0.05). Our data suggest that proactive treatment of pre-existing PEM could be essential for optimal post-stroke recovery
ะัะตะฝะบะฐ ะธะทะผะตะฝัะธะฒะพััะธ ััะพะฒะฝะตะน ะพัะดะตะปัะฝัั ะผะตัััะต ะฝะฐ ัะตะบะต ะะฝะณััะธ ััะฐะฝัะธั ะฅะฐะธัะธ
แแแงแแแแแแแ แแแแแแ แ แแแแฃแ แแ แก. แฎแแแจแแแ แชแแแแแฃแแ แแแแแแแก แแแแแแแแก แชแแแแแแแแแแแก แจแแกแแฎแแ, แกแแแแช แแแแแแ แแแแแก แกแแฌแงแแก แแขแแแแ แฌแงแแแก แแแแแก แแแแแชแแแแแ แกแแแแแแ แแแแแแแ แแ แแแแแฌแแแฃแแแ แฌแงแแแแแแแ แแแแแแ, แ แแก แแแแแช แแแ แฆแแแฃแแแ แแ แแชแแกแแก แแ แแแแแ แแแแแแ. แแแแกแแแแแแ, แขแ แแแแแก แจแแคแแกแแแแก แกแแแแแฎแ แแแแแแแแ แแแ แแแ แแแแแจแ แแแขแแ แแฅแขแฃแแแฃแ แ แแแฎแแ, แ แแแแแ แซแแแแแ แแแแจแแแแแแแแแแ แฐแแแ แแแแขแแแ แแแแแแฃแ แ แแ แแชแแกแแแแก แกแแแแแแแ แชแแแแแแแแแแแก แแแแแแแแแก แจแแกแฌแแแแ, แแแแแ แแแแแแขแแก แชแแแแแแแแก แแแแแแแแแแก แแแ แแแแแจแ.It discusses the variability of individual month levels on the Enguri river station Khaisi, where the water level data at the initial stage of observation is quite low and caused by floods, thus disrupting the uniformity of the process. At the same time, the issue of estimating the trend has become more relevant in modern conditions, as it is very important to study the dynamics of the magnitude of variations in hydrometeorological processes under the influence of climate change.ะัะธะฒะตะดะตะฝั ะธะทะผะตะฝัะธะฒะพัั ััะพะฒะฝะตะน ะพัะดะตะปัะฝัั
ะผะตัััะตะฒ ะฝะฐ ัะตะบะต ะะฝะณััะธ ััะฐะฝัะธั ะฅะฐะธัะธ, ะณะดะต ะดะฐะฝะฝัะต ะพะฑ ััะพะฒะฝะต ะฒะพะดั ะฝะฐ ะฝะฐัะฐะปัะฝะพะผ ััะฐะฟะต ะฝะฐะฑะปัะดะตะฝะธั ะดะพะฒะพะปัะฝะพ ะฝะธะทะบะธ ะธ ะฒัะทะฒะฐะฝั ะฟะพะฒะพะดะบะฐะผะธ, ััะพ ะฝะฐัััะฐะตั ัะฐะฒะฝะพะผะตัะฝะพััั ะฟัะพัะตััะฐ. ะ ัะพ ะถะต ะฒัะตะผั ะฒะพะฟัะพั ะพัะตะฝะบะธ ััะตะฝะดะฐ ััะฐะป ะฑะพะปะตะต ะฐะบััะฐะปัะฝัะผ ะฒ ัะพะฒัะตะผะตะฝะฝัั
ััะปะพะฒะธัั
, ัะฐะบ ะบะฐะบ ะพัะตะฝั ะฒะฐะถะฝะพ ะธะทััะธัั ะดะธะฝะฐะผะธะบั ะฒะตะปะธัะธะฝั ะฒะฐัะธะฐัะธะน ะณะธะดัะพะผะตัะตะพัะพะปะพะณะธัะตัะบะธั
ะฟัะพัะตััะพะฒ ะฟะพะด ะฒะปะธัะฝะธะตะผ ะธะทะผะตะฝะตะฝะธั ะบะปะธะผะฐัะฐ
Elemental characterisation of the pyramidal neuron layer within the rat and mouse hippocampus.
A unique combination of sensitivity, resolution, and penetration make X-ray fluorescence imaging (XFI) ideally suited to investigate trace elemental distributions in the biological context. XFI has gained widespread use as an analytical technique in the biological sciences, and in particular enables exciting new avenues of research in the field of neuroscience. In this study, elemental mapping by XFI was applied to characterise the elemental content within neuronal cell layers of hippocampal sub-regions of mice and rats. Although classical histochemical methods for metal detection exist, such approaches are typically limited to qualitative analysis. Specifically, histochemical methods are not uniformly sensitive to all chemical forms of a metal, often displaying variable sensitivity to specific "pools" or chemical forms of a metal. In addition, histochemical methods require fixation and extensive chemical treatment of samples, creating the strong likelihood for metal redistribution, leaching, or contamination. Direct quantitative elemental mapping of total elemental pools, in situ within ex vivo tissue sections, without the need for chemical fixation or addition of staining reagents is not possible with traditional histochemical methods; however, such a capability, which is provided by XFI, can offer an enormous analytical advantage. The results we report herein demonstrate the analytical advantage of XFI elemental mapping for direct, label-free metal quantification, in situ within ex vivo brain tissue sections. Specifically, we definitively characterise for the first time, the abundance of Fe within the pyramidal cell layers of the hippocampus. Localisation of Fe to this cell layer is not reproducibly achieved with classical Perls histochemical Fe stains. The ability of XFI to directly quantify neuronal elemental (P, S, Cl, K, Ca, Fe, Cu, Zn) distributions, revealed unique profiles of Fe and Zn within anatomical sub-regions of the hippocampus i.e., cornu ammonis 1, 2 or 3 (CA1, CA2 or CA3) sub-regions. Interestingly, our study reveals a unique Fe gradient across neuron populations within the non-degenerating and pathology free rat hippocampus, which curiously mirrors the pattern of region-specific vulnerability of the hippocampus that has previously been established to occur in various neurodegenerative diseases
Calculation of the maximum discharges of river freshets in the case of the Vere River
แ แแแแ แช แแแแแแ แแแแแแแแแ แฉแแแก, แแแแแแ แ แแแ แแก แฐแแแ แแแแแแฃแ แ แ แแแแแ, แฌแแแก แแแแ แแแ แแแแจแ, แฃแแชแแ แ แแแแกแฎแแ แฌแแแแแแแก แจแแแแแแ, แฎแแกแแแแแแแ แแแแ แฌแงแแแแแแแ แแแแแแ. แแแแแแขแแก แแแแแแแฃแ แชแแแแแแแแกแแแ แแแแแแจแแ แแแแ, แแแแกแแแฃแแ แแแแ 1990-แแแแ แฌแแแแแก แจแแแแแแแ แแแ แแแแแแแ, แแแฎแจแแ แแ แแแแ แ แแแแแแแแ แแ แกแแซแแแแ แ. แฌแงแแแแแแแ แแแแแแก แแแฅแกแแแแแฃแ แ แฎแแ แฏแแแแก แแแแแแ แจแแแแก แคแแ แแฃแแแก แแแแแงแแแแแแ แซแแ แแแแแแ แแแชแแแฃแแแ แชแฎแ แแแ 1-แแก แกแแฎแแ. แกแขแแขแแแจแ, แแแแแแแแแก แกแแฎแแ, แแแแแแ แ แแแ แแแ 2015 แฌแแแก 14 แแแแแกแแก แแแขแแกแขแ แแคแฃแแ แฌแงแแแแแแแ แแแแก แฎแแ แฏแแก แแแแแแ แแแคแแขแแ แแแแก แฎแแแแก แจแแแ แแแแแก แจแแแแแ แแแแแแแแ แ แแแแแแกแแแแแก แแแชแแแฃแแแ 2 แแแแแแแ - แกแแแแแแแกแแแก แแ แจแแแแก แคแแ แแฃแแแแแก แแแแแงแแแแแแ, แฎแแแ แแแคแแขแแ แแแแก แฎแแแแแ แแแแแแแแ แแแฅแกแแแแแฃแ แ แฎแแ แฏแแก แแแฎแแแแแ แแแแแ แแขแแ แแแก แแแแแแกแแแแแก แแ แแแแแแแแ แแแแแแ แ แแแ แแก แแฃแแแกแแแแแก แแแแ แคแแ แแแแแแแก แคแแ แแแแแแ แแแแคแแชแแแแขแแแแก แแแแแงแแแแแแ แแแฆแแแฃแแแ 14 แแแแแกแแก แแแขแแกแขแ แแคแฃแแ แฌแงแแแแแแแ แแแแก แแแฅแกแแแแแฃแ แ แฎแแ แฏแแแแก แแแแจแแแแแแแแแ แจแแกแแแแแแกแแ 477 แแ 512 แ3 /แฌแ แแแแแแแแ. แแแแกแแแแแแ, แฃแแแ แแฆแแแแจแแแก, แ แแ แแแคแแขแแ แแแแก แฎแแแแแ แแ แกแแแฃแแ แแแฅแกแแแแแฃแ แ แฎแแ แฏแแแแก แกแแแแแ แจแแแแแแก แจแแแแ แแแแ แฉแแแก, แ แแ แแกแแแ แกแแแแแแ แแฎแแแก แแ แแแ แแ แแแแแแแแแ, แ แแช แแแแแแแแจแแแแก แฉแแแแก แแแแ แแแแแ แแขแแ แแแก แแแแแจแ 1990-แแแแ แฌแแแแแแแ แแแงแแแแแฃแแ แแฆแแแแแแแ แแฆแแแแ แจแแแแก แคแแ แแฃแแแก แแแแแงแแแแแแ แแแแแแแแ แฌแงแแแแแแแ แแแแแแก แแแฅแกแแแแแฃแ แ แฎแแ แฏแแแแก แกแแแแแแแแแแแ.As the observations show, the hydrological regime of the Vere River, in the warm period of the year, as a result of sudden heavy rains, is characterized by large freshets. Due to global climate change, especially since the 1990s, their number and intensity have increased. Calculation of the maximum discharges of freshets using Chezy formula is mainly given in the form of Table 1. In the article, as an example, the calculation of the discharge of the catastrophic freshet on the Vere River on 14 June 2015 for the adjacent section after the connection of the Napetvrebi ravine is given by 2 methods - using the Sokolovsky and Chezy formulas, and according to the maximum discharge calculated at the Napetvrebi ravine for the laboratory section and for the entire Vere river basin using the relative coefficients of their areas, the values of the maximum discharges of the June 14 catastrophic freshet were obtained in the amount of 477 and 512 m 3 /s, respectively. In addition, it should be noted that comparing all three results of the maximum discharges at Napetvrebi ravine, it can be seen that they are quite close to each other, which indicates the credibility of the maximum discharges of freshets calculated by us in the laboratory section from the 1990s to the present day using the Chezy formula