Publications by authors named "Luis M Zieher"

Acute and long-term complications can occur in patients receiving radiation therapy. It has been suggested that cytoprotection might decrease the incidence and severity of therapy-related toxicity in these patients. Developing cerebellum is highly radiosensitive and for that reason it is a useful structure to test potential neuroprotective substances to prevent radiation induced abnormalities.

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The issue of psychotic disorders in epilepsy has given rise to great controversy among professionals; however, there are not many studies in this area and the physiopathological mechanisms remain unknown. The aim of this study was to describe the spectrum of psychotic disorders in an Argentine population with refractory temporal lobe epilepsy (RTLE) and to determine the risk factors associated with psychotic disorders. Clinical variables of the epileptic syndrome were compared among a selected population with RTLE with and without psychotic disorders (DSM-IV/Ictal Classification of psychoses).

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Several studies have demonstrated a controversial involvement of NO in epileptogenesis. The aim of this study is to compare the NADPH diaphorase (NADPH-d) reactivity in the temporal cortex between surgical specimens of patients with intractable epilepsy and hippocampal sclerosis and autopsy controls. Brain samples of patients and postmortem controls were stained with the NADPH-d technique.

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In this study, we show that one single dose of gamma-irradiation at birth induces an inhibition of the cerebellar calcium dependent nitric oxide synthase (NOS) activity, probably correlated to the motor abnormalities and the disarrangement in the cerebellar cytoarchitecture observed in adult rats. This decrease in calcium dependent NOS activity could be associated with an increased protein kinase C (PKC) activity. PKC inhibition partially restores calcium dependent NOS activity, indicating that PKC activity could be negatively modulating the catalytic activity of calcium dependent NOS.

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Developing central nervous system (CNS) is highly sensitive to ionizing radiation due, in part, to reactive oxygen species (ROS) damage. A variety of compounds able to protect brain cells essentially by decreasing ROS production have been widely used to confirm ROS participation in different mechanisms of brain injury, as well as to evaluate them as therapeutic tools. To test if ionizing radiation-induced damage on immature cerebellar granule cells is mainly mediated by ROS accumulation, a free radical scavenger--amifostine (amf)--was used in an in vitro model.

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Oxidative stress has been implicated in the pathogenesis of many neurodegenerative and neurological disorders, with reactive oxygen species (ROS) as part of the intracellular effectors of damage formed in the presence of an excess of iron. Ionizing radiation induces tissue damage on developing CNS through different simultaneous mechanisms, including ROS-induced oxidative damage; therefore, exogenously added iron chelators might contribute to protect cells from free-radical injury. Cerebellar granule cells grown in vitro were exposed to 0.

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There is considerable evidence that the sympathetic nervous system influences the immune response via activation and modulation of beta(2)-adrenergic receptors (beta(2)R). Furthermore, it has been suggested that stress has effects on the sympathetic nervous system. In the present study, we analyzed the influence of catecholamines on the reactivity of lymphocytes from mice exposed to a chronic mild stress (CMS) model of depression (CMS-animals).

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