Publications by authors named "TA Fisher"

The ability of the mammalian brain to maintain spatial representations of external or internal information for short periods of time has been associated with sustained neuronal spiking and reverberatory neural network activity in the medial entorhinal cortex. Here, we show that conditional genetic deletion of netrin-1 or the netrin receptor deleted-in-colorectal cancer (DCC) from forebrain excitatory neurons leads to deficits in short-term spatial memory. We then demonstrate that conditional deletion of either netrin-1 or DCC inhibits cholinergic persistent firing and show that cholinergic activation of muscarinic receptors expressed by entorhinal cortical neurons promotes persistent firing by recruiting DCC to the plasma membrane.

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Mesial temporal lobe epilepsy (MTLE) is the most common form of focal epilepsy and it is characterized by seizures that are often refractory to medications. Seizures in MTLE have two main patterns of onset that have been termed hypersynchronous (HYP) and low-voltage fast (LVF) and are believed to mainly depend on the activity of excitatory principal cells and inhibitory interneurons, respectively. In this study, we investigated whether unilateral open-loop optogenetic activation of CaMKII-positive principal cells in the hippocampus CA3 region favors the generation of spontaneous HYP seizures in kainic acid-treated (KA) CaMKII-ChR2 mice.

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Article Synopsis
  • The study aimed to evaluate the biological age of middle-aged individuals engaged in hardening practices, focusing on differences based on gender and additional sports activities.
  • It involved 63 participants (36 women and 27 men), using bioimpedance analysis to assess body composition and determine biological age through established methods.
  • Results indicated that participants had a higher body mass index than normal, but those involved in hardening showed a lower biological age compared to their calendar age, suggesting that hardening may positively impact physiological health and aging.
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Unlabelled: The article shows the influence of repeated repetition of contrasting temperature effects on hemodynamic, psychophysiological parameters and the adaptive potential of men of working age.

Objective: To assess changes of hemodynamic and psychophysiological parameters, as well as the adaptive potential in healthy men of working age under the influence of repeated contrasting temperature exposures, the difference of which is about 70 °C.

Material And Methods: Blood pressure, heart rate and Luscher test were measured 20 minutes before and 20 minutes after repeated exposure of contrasting temperature changes (alternation of temperature cycles).

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Unlabelled: The data presented in this article illustrate the dynamics of the affective sphere of the mental processes associated with the higher nervous activity and the characteristics of the neuroendocrine system (including the vegetative index of Kerdo, cortisol and serotonin levels) in the participants of the marathon swimming competition covering the distance of 101.4 km. We investigated the relationship between the levels of the above hormones and the functional activity of the vegetative nervous system.

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The immunobiological potential of a new microorganism species isolated from permafrost specimens (PMO strain 3M) collected from the Mammoth Mountain in Yakutia was studied in laboratory mice. PMO injected intraperitoneally in doses of 2500 to 50 × 10(6) microbial bodies caused characteristic dose-dependent effects on the structure and functions of the immune system (thymus and spleen indexes, functional activity of splenic macrophages, cellular and humoral immunity). Doses of PMO stimulating functional activities of both cellular and humoral immunity were detected.

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Microorganisms of genus Bacillus strain 3M (permafrost microorganisms--PM), allocated from the samples of permafrost soils from Mamontova Mountain (Yakutia) are influenced by the quality and duration of life of elderly mice. PMs were injected intraperitoneally to CBA mice at the age of 17 months. Motion activity, muscular force (lifting of cargo test), food instinct activity (dosed starvation test) and cellular immunity activity (reaction of delayed-type hypersensitivity in vivo) of animals have increased, and psychoemotional condition of animals has improved under influence of PM.

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Experiments on inbred animals showed that short-term exposure in cold water significantly modified structural and functional parameters of the immune system at different levels of its organization, from bone marrow hemopoiesis to effector stage of the immune response to antigen. The thermal factor caused changes in nonspecific and specific mechanisms of the immune system. Hypothermal exposure (7-9 degrees C, 5 sec) increased the thymic index and bone marrow lymphocyte count, reduced absorption capacity and stimulated metabolic activity of phagocytes, stimulated cell-mediated and suppressed humoral immunity.

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In this qualitative study, we explored the question of why some women with progressive forms of multiple sclerosis (MS) cope successfully in spite of disease progression. Ten women with progressive courses of MS, the more physically challenging forms of the disease, who self-reported as coping successfully with the disease, participated in the study. The study features an interview protocol using a psychotherapeutic model of change, precursors of change model, and incorporates a then-post design.

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Transient changes in environmental temperature produce a short-term, but significant effect on the immune system reactions in laboratory mice. Activities of nonspecific resistance factors (peritoneal macrophages) in mice exposed in warm or cold water were characterized by similar reactions, while the reactions of cellular and humoral immunity were opposite. Exposure to cold water activated cellular immunity, while warm water activated humoral immune system.

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The lymph node diagnostic clinic was set up at the Royal Marsden Hospital to provide a direct access service for general practitioners. In the first year 82 patients were seen. The malignancy pick-up rate was 19.

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We have previously reported that neuropeptide Y (NPY), a sympathetic cotransmitter and vasoconstrictor, is mitogenic for vascular smooth muscle cells (VSMCs), and now report on the mechanisms mediating these effects. In rat aortic A10 cell line, NPY's potency was greater than that of norepinephrine, and efficacy similar to that of platelet-derived growth factor, but less than that of the full serum, in stimulating cell proliferation; this effect was optimal in cell 60-80% cell density. At lower cell density and serum content, NPY stimulated DNA fragmentation/apoptosis.

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