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According to some studies, 80% of subjects suffering from post-traumatic stress disorder (PTSD) present twice the risk of developing an insanity as they age because of the high level of stress that has been induced. Indeed, the triggered trauma has a deleterious effect on the establishment of the stress’ axis (the hypothalamic pituitary adrenal axis) which is then not able to regulate itself. As a consequence, the hippocampal neurons will be attacked by an excess of cortisol. Memory's dysfunction is central in the symptomatology of PTSD, particularly in respect to encoding and recall. The hippocampus is able to transfer information to the prefrontal cortex. Actually, subjects with PTSD present less activity in the prefrontal cortex triggered by a decrease of encoding and recall capacities. EMDR therapy (eye movement desensitization and recruitment) allow for a fast relief of symptoms by a bilateral alternate stimulation (SBA). Indeed, saccadic eye movements stem affect related to the traumatic event and process the associated cognitions. During the desensitization phase in EMDR, we noticed an increase in activity of the brain's prefrontal, ventromedial, amygdala and thalamic regions. Indeed, the recall of traumatic memories goes through implicit emotional valence regions and associative areas for which the experience is already deeply integrated. After comparing cerebral activity before and after the therapy, researches on EMDR shows that a reduction of stress’ symptoms has some sensitive link to PTSD (in prevention to dementia). [ABSTRACT FROM AUTHOR]

Purpose: To present the impact in coverage of different methods for Poisson confidence intervals and the impact in dose coverage of different uncertainty factors. A detailed explanation of the uncertainty sources in the Bayesian method is also presented. Materials and methods: The exact coverage of uncertainty Poisson confidence intervals and the dose uncertainty interval coverage were performed by simulations using R-based scripts. Results: The Poisson exact calibration interval via the Modified Crow and Gardner method resulted in coverage quite close to the nominal level of confidence; additionally, the method retains the shortest property of Crow and Gardner, and gains the property of a lower limit strictly increasing in the mean of dicentrics. The unlimited simultaneous calibration interval seems to be the method of choice to preserve the coverage at 95% under parametric and nonparametric conditions but is a conservative method. When samples came from a Poisson distribution, the ISO propagation of errors and Bayesian approaches seem to be the closest to the 95% coverage. Conclusions: The Modified Crow and Gardner method should be preferred over the Garwood method for Poisson exact confidence intervals. The unlimited simultaneous calibration interval did not lose its property to preserve the coverage at 95% applying a regression coverage factor of value 2.02 at the point of doses studied in the simulation. [ABSTRACT FROM AUTHOR]

In this paper, the use of lithium fluoride (LiF) as imaging radiation detector to analyse living cells by single-shot soft X-ray contact microscopy is presented. High resolved X-ray images on LiF of cyanobacterium Leptolyngbya VRUC135, two unicellular microalgae of the genus Chlamydomonas and mouse macrophage cells (line RAW 264.7) have been obtained utilizing X-ray radiation in the water window energy range from a laser plasma source. The used method is based on loading of the samples, the cell suspension, in a special holder where they are in close contact with a LiF crystal solid-state X-ray imaging detector. After exposure and sample removal, the images stored in LiF by the soft X-ray contact microscopy technique are read by an optical microscope in fluorescence mode. The clear image of the mucilaginous sheath the structure of the filamentous Leptolyngbya and the visible nucleolus in the macrophage cells image, are noteworthiness results. The peculiarities of the used X-ray radiation and of the LiF imaging detector allow obtaining images in absorption contrast revealing the internal structures of the investigated samples at high spatial resolution. Moreover, the wide dynamic range of the LiF imaging detector contributes to obtain high-quality images. In particular, we demonstrate that this peculiar characteristic of LiF detector allows enhancing the contrast and reveal details even when they were obscured by a nonuniform stray light. [ABSTRACT FROM AUTHOR]

Abstract: Objective: Repetitive Transcranial Magnetic Stimulation (rTMS) has been recently employed as a therapeutic strategy for stroke, although its effects on cerebral hemodynamics has been poorly investigated. This study aims to examine the impact of high frequency rTMS on cerebral vasomotor reactivity (VMR). Methods: Twenty-nine healthy subjects were randomly assigned to real (19) or sham 17-Hz rTMS, applied on primary motor cortex (M1) of the dominant hemisphere. All subjects underwent Transcranial Doppler of the middle cerebral arteries to evaluate mean flow velocity and VMR before (T 0) and within 10min (T 1) following rTMS. Four subjects underwent further VMR evaluations at 2 (T 2), 5 (T 3) and 24h (T 4) after rTMS. As a control condition, 10 subjects underwent real (5) or sham rTMS on calcarine cortex. In addition, five acute stroke patients underwent five daily rTMS sessions on the affected hemisphere mimicking a therapeutic trial. Results: Following real rTMS on M1 (p =0.002) and calcarine cortex (p <0.001) VMR decreased with respect to T 0 in both hemispheres, while no change was observed after sham rTMS (p >0.6). VMR tended to remain lower than T 0 until T 3. Cerebral VMR decreased independently of the stimulated side also in the patients’ group. Conclusions: High frequency rTMS reduces cerebral VMR, possibly as a secondary effect on autonomic control of cerebral hemodynamics. Significance: The effect of rTMS on cerebral hemodynamics should be carefully considered before proceeding toward a therapeutic application in stroke patients. [Copyright &y& Elsevier]

The main objective of the study was the evaluation of the efficacy and homogeneity with which the laboratories of the region carry out biological dosimetry using the two most useful at the present time cytogenetic indicators: the frequency of dicentrics (dicentrics and rings) and that of micronuclei in human lymphocytes. The intercomparison was carried out from codes slides. The gamma radiation doses employed were 0.7,5, 1.5 and 3 Gy. One sample was not irradiated. In the ± 30% of the true dose interval were included 11 out of 15 doses calculated by dicentrics frequency and 9 out of 12 doses calculated by micronuclei frequency. The true doses were in the interval established with 95% confidence limit in 10 out of 12 dose intervals estimated by micronuclei frequency and in 9 out of 15 dose intervals estimated by dicentrics frequency. The laboratory results were similar. [ABSTRACT FROM AUTHOR]

Purpose Transcranial electric stimulations (tES) with amplitude-modulated currents are promising tools to enhance neuromodulation effects. It is essential to select the correct cortical targets and inhibitory/excitatory protocols to reverse changes in specific networks. We aimed at assessing the dependence of cortical excitability changes on the current amplitude of 20 Hz transcranial alternating current stimulation (tACS) over the bilateral primary motor cortex. Methods We chose two amplitude ranges of the stimulations, around 25 μ A/cm2 and 63 μ A/cm2 from peak to peak, with three values (at steps of about 2.5%) around each, to generate, respectively, inhibitory and excitatory effects of the primary motor cortex. We checked such changes online through transcranial magnetic stimulation (TMS)-induced motor evoked potentials (MEPs). Results Cortical excitability changes depended upon current density (p=.001). Low current densities decreased MEP amplitudes (inhibition) while high current densities increased them (excitation). Conclusions tACS targeting bilateral homologous cortical areas can induce online inhibition or excitation as a function of the current density. [ABSTRACT FROM AUTHOR]