46 research outputs found

    Mouse visual cortex contains a region of enhanced spatial resolution.

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    The representation of space in mouse visual cortex was thought to be relatively uniform. Here we reveal, using population receptive-field (pRF) mapping techniques, that mouse visual cortex contains a region in which pRFs are considerably smaller. This region, the "focea," represents a location in space in front of, and slightly above, the mouse. Using two-photon imaging we show that the smaller pRFs are due to lower scatter of receptive-fields at the focea and an over-representation of binocular regions of space. We show that receptive-fields of single-neurons in areas LM and AL are smaller at the focea and that mice have improved visual resolution in this region of space. Furthermore, freely moving mice make compensatory eye-movements to hold this region in front of them. Our results indicate that mice have spatial biases in their visual processing, a finding that has important implications for the use of the mouse model of vision

    Localization of Mineralocorticoid Receptors at Mammalian Synapses

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    In the brain, membrane associated nongenomic steroid receptors can induce fast-acting responses to ion conductance and second messenger systems of neurons. Emerging data suggest that membrane associated glucocorticoid and mineralocorticoid receptors may directly regulate synaptic excitability during times of stress when adrenal hormones are elevated. As the key neuron signaling interface, the synapse is involved in learning and memory, including traumatic memories during times of stress. The lateral amygdala is a key site for synaptic plasticity underlying conditioned fear, which can both trigger and be coincident with the stress response. A large body of electrophysiological data shows rapid regulation of neuronal excitability by steroid hormone receptors. Despite the importance of these receptors, to date, only the glucocorticoid receptor has been anatomically localized to the membrane. We investigated the subcellular sites of mineralocorticoid receptors in the lateral amygdala of the Sprague-Dawley rat. Immunoblot analysis revealed the presence of mineralocorticoid receptors in the amygdala. Using electron microscopy, we found mineralocorticoid receptors expressed at both nuclear including: glutamatergic and GABAergic neurons and extra nuclear sites including: presynaptic terminals, neuronal dendrites, and dendritic spines. Importantly we also observed mineralocorticoid receptors at postsynaptic membrane densities of excitatory synapses. These data provide direct anatomical evidence supporting the concept that, at some synapses, synaptic transmission is regulated by mineralocorticoid receptors. Thus part of the stress signaling response in the brain is a direct modulation of the synapse itself by adrenal steroids

    Long-Term Continuous Corticosterone Treatment Decreases VEGF Receptor-2 Expression in Frontal Cortex

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    Objective: Stress and increased glucocorticoid levels are associated with many neuropsychiatric disorders including schizophrenia and depression. Recently, the role of vascular endothelial factor receptor-2 (VEGFR2/Flk1) signaling has been implicated in stress-mediated neuroplasticity. However, the mechanism of regulation of VEGF/Flk1 signaling under longterm continuous glucocorticoid exposure has not been elucidated. Material and Methods: We examined the possible effects of long-term continuous glucocorticoid exposure on VEGF/Flk1 signaling in cultured cortical neurons in vitro, mouse frontal cortex in vivo, and in post mortem human prefrontal cortex of both control and schizophrenia subjects. Results: We found that long-term continuous exposure to corticosterone (CORT, a natural glucocorticoid) reduced Flk1 protein levels both in vitro and in vivo. CORT treatment resulted in alterations in signaling molecules downstream to Flk1 such as PTEN, Akt and mTOR. We demonstrated that CORT-induced changes in Flk1 levels are mediated through glucocorticoid receptor (GR) and calcium. A significant reduction in Flk1-GR interaction was observed following CORT exposure. Interestingly, VEGF levels were increased in cortex, but decreased in serum following CORT treatment. Moreover, significant reductions in Flk1 and GR protein levels were found in postmortem prefrontal cortex samples from schizophrenia subjects. Conclusions: The alterations in VEGF/Flk1 signaling following long-term continuous CORT exposure represents a molecula

    Vitamin D3 (Cholecalciferol) and Pelvic Pain Caused by Ovarian Endometriosis

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    Статья посвящена изучению взаимосвязи концентрации витамина D с наличием и интенсивностью тазовой боли у женщин, страдающих эндометриозом яичников. Цель исследования: установить взаимосвязь уровня витамина D и интенсивности тазовой боли у женщин, страдающих эндометриозом яичников. В исследование были включены 190 женщин репродуктивного возраста с верифицированным диагнозом эндометриоз яичников, в возрасте от 20 до 41 года (средний возраст – 29,1±3,3 года). Для определения интенсивности тазовой боли использовали визуальную аналоговую шкалу (ВАШ). Всем пациенткам (n=190) исходно оценку уровня витамина D проводили путем определения уровня общего 25(ОН)D в сыворотке крови методом масс-спектрометрии, адаптированным к клинической практике, согласно международным стандартам, на тандемном масс-спектрометре AB SCIEX QTRAP 5500.The article studies the relation between vitamin D concentration and the presence and intensity of pelvic pain in women suffering from ovarian endometriosis. The aim of the study is to examine the relation between vitamin D levels and intensity of pelvic pain in women with ovarian endometriosis. Study design: cohort, prospective, non-comparative study. The study included 190 women of reproductive age suffering from ovarian endometriosis (OE), aged 20 to 41 years (mean age 29.1±3.3 years). Visual analogue scale (VAS) was used to determine the intensity of pelvic pain.The evaluation of vitamin D level in all patients (n=190) was initially performed by determining the level of total 25 (OH) D in blood serum by the method of mass spectrometry. Study Results: The average vitamin D level in the study was 23.98±6.82 ng/ml. The average concentration of vitamin D in the blood of the patients with low-intensity pelvic pain was 26.7±5.92 ng/ml, with moderate-intensity – 23.06±of 5.55 ng/ml, with high pain intensity – 19.26±6,01 ng/ml. The content of vitamin D in the blood of the patients in the control group was 28.83±6.15 ng/ml, which met the criteria of insufficiency. Аn inverse correlation between the severity of pain based on VAS and vitamin D in women with endometriosis of the main group was established in the study, it amounted to 0.502 (p<0.001)

    Overexpression of Mineralocorticoid Receptors in the Mouse Forebrain Partly Alleviates the Effects of Chronic Early Life Stress on Spatial Memory, Neurogenesis and Synaptic Function in the Dentate Gyrus

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    Evidence from human studies suggests that high expression of brain mineralocorticoid receptors (MR) may promote resilience against negative consequences of stress exposure, including childhood trauma. We examined, in mice, whether brain MR overexpression can alleviate the effects of chronic early life stress (ELS) on contextual memory formation under low and high stress conditions, and neurogenesis and synaptic function of dentate gyrus granular cells. Male mice were exposed to ELS by housing the dam with limited nesting and bedding material from postnatal day (PND) 2 to 9. We investigated the moderating role of MRs by using forebrain-specific transgenic MR overexpression (MR-tg) mice. Low-stress contextual (i.e., object relocation) memory formation was hampered by ELS in wildtype but not MR-tg mice. Anxiety like behavior and high-stress contextual (i.e., fear) memory formation were unaffected by ELS and/or MR expression level. At the cellular level, an interaction effect was observed between ELS and MR overexpression on the number of doublecortin-positive cells, with a significant difference between the wildtype ELS and MR-tg ELS groups. No interaction was found regarding Ki-67 and BrdU staining. A significant interaction between ELS and MR expression was further observed with regard to mEPSCs and mIPSC frequency. The ratio of evoked EPSC/IPSC or NMDA/AMPA responses was unaffected. Overall, these results suggest that ELS affects contextual memory formation under low stress conditions as well as neurogenesis and synaptic transmission in dentate granule cells, an effect that can be alleviated by MR-overexpression

    Perspektywy wykorzystania magazynów energii w procesie produkcji energii słonecznej

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    Every developing country is beginning to rely on “green” energy in connection with environmental problems, including the global warming of our planet. It is expected that in the future, the production of electricity using the conversion of sunlight would take the dominant place in the energy infrastructure around the world. However, photovoltaic converters mainly generate intermittent energy due to natural factors (weather conditions) or the time of day in a given area. Therefore, the purpose of this study is to consider options for eliminating the interrupted nature of the operation of a solar installation through innovative additional applications. To achieve this goal, issues of the prospect of using energy storage devices and the choice of the most efficient and reliable of them are considered, as are the environmental friendliness of accumulators/batteries and the economic benefits of their use. The results of the analyses provide an understanding of the factors of using existing technologies with regard to their technical and economic aspects for use in solar energy. It was determined that the most common and predominant types of energy storage are lithium-ion and pumped storage plants. Such accumulation systems guarantee high efficiency and reliability in the operation of solar installation systems, depending on the scale of the solar station. Storage devices that are beginning to gain interest in research are also considered – storage devices made of ceramics of various kinds and thermochemical and liquid-air technologies. This study contributes the development of an energy-storage system for renewable energy sources in the field of technical and economic optimization.Każdy kraj rozwijający się zaczyna polegać na „zielonej” energii w związku z problemami środowiskowymi, w tym globalnym ociepleniem naszej planety. Oczekuje się, że w przyszłości produkcja energii elektrycznej z wykorzystaniem konwersji światła słonecznego zajmie nadrzędne miejsce w infrastrukturze energetycznej na całym świecie. Jednak konwertery fotowoltaiczne generują energię głównie w sposób przerywany ze względu na czynniki naturalne (warunki pogodowe) lub porę dnia na danym terenie. Dlatego celem niniejszego opracowania jest rozważenie możliwości wyeliminowania przerywanej pracy instalacji solarnej poprzez innowacyjne aplikacje dodatkowe. Aby osiągnąć ten cel, rozważane są kwestie perspektywy wykorzystania magazynów energii oraz wyboru najbardziej wydajnych i niezawodnych z nich, a także akumulatorów/baterii w aspekcie ich oddziaływania na środowisko i korzyści ekonomicznych z ich użytkowania. Wyniki analiz pozwalają na zrozumienie czynników wykorzystania istniejących technologii, ich technicznych i ekonomicznych aspektów wykorzystania w energetyce słonecznej. Stwierdzono, że najpowszechniejszymi i dominującymi rodzajami magazynowania energii są elektrownie litowo-jonowe oraz elektrownie szczytowo-pompowe. Takie układy akumulacyjne gwarantują wysoką sprawność i niezawodność działania systemu instalacji solarnej, w zależności od skali stacji solarnej. Rozważane są również urządzenia magazynujące, które zaczynają coraz bardziej interesować badaczy – urządzenia magazynujące wykonane z różnego rodzaju ceramiki, w technologii termochemicznej i cieczowo-powietrznej. Niniejsze opracowanie przyczynia się do rozwoju systemu magazynowania energii dla odnawialnych źródeł energii w zakresie optymalizacji technicznej i ekonomicznej

    EVALUATION OF PAIN SYNDROME IN PATIENTS WITH ENDOMETRIOSIS-ASSOCIATED PELVIC PAIN CAUSED BY EXTERNAL GENITAL ENDOMETRIOSIS

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    The aim of the study was to evaluate the severity of pain syndrome and depression syndrome in women with endometriosis- associated pelvic pain. Materials and methods. The study included 100 women of reproductive age with external genital endometriosis. The study group consisted of 60 patients with pelvic pain associated with external genital endometriosis; the control group consisted of 40 women with external genital endometriosis without pain. The pelvic pain was ranked using the Visual Analog Scale (VAS); the level of depression was evaluated using the Beck scale; the anxiety was rated according to the Spielberger-Khanin questionnaire. Results. Among the 60 women in the study group, 20 patients (33.3%) had severe pain, 25 women (41.6%) had moderately severe pain, and 15 women (25.1%) had mild pain. The occurrence of depressive disorders in women with endometriosis-associated pelvic pain was 64%. Conclusion. The results suggest that the psycho-emotional status of women with external genital endometriosis-associated pelvic pain is dominated by high level of depression and anxiety, which significantly downgrades their quality of life

    Rodent stereotaxic surgery and animal welfare outcome improvements for behavioral neuroscience

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    Item does not contain fulltextStereotaxic surgery for the implantation of cannulae into specific brain regions has for many decades been a very successful experimental technique to investigate the effects of locally manipulated neurotransmitter and signaling pathways in awake, behaving animals. Moreover, the stereotaxic implantation of electrodes for electrophysiological stimulation and recording studies has been instrumental to our current understanding of neuroplasticity and brain networks in behaving animals. Ever-increasing knowledge about optimizing surgical techniques in rodents(1-4), public awareness concerning animal welfare issues and stringent legislation (e.g., the 2010 European Union Directive on the use of laboratory animals(5)) prompted us to refine these surgical procedures, particularly with respect to implementing new procedures for oxygen supplementation and the continuous monitoring of blood oxygenation and heart rate levels during the surgery as well as introducing a standardized protocol for post-surgical care. Our observations indicate that these modifications resulted in an increased survival rate and an improvement in the general condition of the animals after surgery (e.g. less weight loss and a more active animal). This video presentation will show the general procedures involved in this type of stereotaxic surgery with special attention to our several modifications. We will illustrate these surgical procedures in rats, but it is also possible to perform this type of surgery in mice or other small laboratory animals by using special adaptors for the stereotaxic apparatus(6).4 p
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