Melatonin and Angelman Syndrome: Implications and Mathematical Model of Diurnal Secretion

The main aim of the study was to compare the melatonin rhythms in subjects with Angelman syndrome (n=9) and in children with (n=80) and without (n=40) epilepsy (nonepileptic patients diagnosed with peripheral nerve palsies, myopathy, and back pain) using our mathematical model of melatonin circadian secretion. The characteristics describing the diurnal hormone secretion such as minimum melatonin concentration, release amplitude, phase shift of melatonin release, and sleep duration as well as the dim light melatonin onset (DLMO) of melatonin secretion and the γ shape parameter allow analyzing the fit and deducing about how much the measured melatonin profile differs from a physiological bell-shaped secretion. The estimated sleep duration and phase shift of melatonin release as well as the DMLO offsets at 25% and 50% relative thresholds are the key characteristic of Angelman syndrome children. As revealed from the γ shape parameter, the melatonin secretion profiles are disturbed in majority of the AG subjects revealing rather a triangular course instead of the bell-like one

Elucidation of the fate of zinc in model plants using single particle ICP-MS and ESI tandem MS

International audienceIn recent years, the increasing use of zinc oxide nanoparticles (ZnO NPs) in many consumer products and industrial applications made them a new potential source of zinc in the environment. After their release into the environment, ZnO NPs can undergo different transformations which are still poorly understood and may influence their potential toxicity. This study investigates for the first time the fate of zinc, supplied in the form of ZnO NPs and ZnCl2, taken up by a model edible plant (lettuce, Lactuca sativa L.) by means of different mass spectrometry techniques. Single particle inductively coupled plasma mass spectrometry (SP-ICP-MS) analysis showed the rapid dissolution of ZnO NPs in the growth medium used for cultivation of lettuce, confirming that only dissolved zinc, not intact NPs, is taken up by plants. Taking into account that the beneficial or toxic effects of zinc depend on its form accumulated by plants, it is crucial to identify the chemical forms of zinc and their distribution in edible plant tissues. Therefore, the second part of this work was focused on the study of zinc speciation in plants cultivated with ZnCl2 by using hyphenated techniques. The proposed approach based on two-dimensional chromatographic (size exclusion – SEC and hydrophilic interaction – HILIC) separation with parallel ICP-MS and ESI-qTOF-MS/ESI-FT-Orbitrap-MS detection allows the determination and identification of minor zinc complexes at environmentally relevant concentrations. Nicotianamine (NA) is shown to be the major ligand binding zinc in lettuce leaves, and the Zn–NA complex is responsible for more than 70% of the total zinc content extracted from lettuce leaves by means of ammonium acetate buffer

Uptake, translocation, size characterization and localization of cerium oxide nanoparticles in radish (Raphanus sativus L.)

International audienceDue to their unique physical and chemical properties, the production and use of cerium oxide nanoparticles (CeO 2 NPs) in different areas, especially in automotive industry, is rapidly increasing, causing their presence in the environment. Released CeO 2 NPs can undergo different transformations and interact with the soil and hence with plants, providing a potential pathway for human exposure and leading to serious concerns about their impact on the ecosystem and human organism. This study investigates the uptake, bioaccumulation, possible translocation and localization of CeO 2 NPs in a model plant (Raphanus sativus L.), whose edible part is in direct contact with the soil where contamination is more likely to happen. The stability of CeO 2 NPs in plant growth medium as well as after applying a standard enzymatic digestion procedure was tested by single particle ICP-MS (SP-ICP-MS) showing that CeO 2 NPs can remain intact after enzymatic digestion; however, an agglomeration process was observed in the growth medium already after one day of cultivation. An enzymatic digestion method was next used in order to extract intact nanoparticles from the tissues of plants cultivated from the stage of seeds, followed by size characterization by SP-ICP-MS. The results obtained by SP-ICP-MS showed a narrower size distribution in the case of roots suggesting preferential uptake of smaller nanoparticles which led to the conclusion that plants do not take up the CeO 2 NPs agglomerates present in the medium. However, nanoparticles at higher diameters were observed after analysis of leaves plus stems. Additionally, a small degree of dissolution was observed in the case of roots. Finally, after CeO 2 NPs treatment of adult plants, the spatial distribution of intact CeO 2 NPs in the radish roots was studied by laser ablation ICP-MS (LA-ICP-MS) and the ability of NPs to enter and be accumulated in root tissues was confirmed

In-bore MR prostate biopsy — initial experience

Introduction: The introduction of multiparametric MRI (mpMRI) has been a breakthrough in the diagnosis of noninvasive clinically significant prostate cancer. Currently, MR-guided prostate biopsy (in-bore biopsy) is the only biopsy method that uses real-time MRI in patients with suspected prostate cancer. The aim of the study was a retrospective analysis of the correlation between MRI results and histological findings of prostate samples suspected of malignancy, which were taken during MRI-guided biopsy. Material and methods: Thirty-nine patients with 57 lesion biopsies were enrolled in the study. Patients were aged 48–84 years (mean age 67.2 ± 9.4 years). Results: Cancer was histologically confirmed in 24 lesions, including primary cancer in 14 lesions and local recurrence in 10 lesions. Cancer was not detected in the remaining lesions (n = 33). Malignancy was confirmed in 90% of lesions previously reported as PI-RADS 5. Only one Prostate Imaging and Reporting and Data System (PI-RADS 5) lesion was histologically negative (prostatitis). Cancer was detected in 50% of lesions defined as PI-RADS 4. Cancer cells were not found in any of 23 lesions defined as PI-RADS 3 (53.5%). Most of the lesions assessed as PI-RADS 3 were located in the transitional zone (n = 19). Only four PI-RADS 3 lesions were found in the peripheral zone. Large lesions or lesions feasible for cognitive TRUS biopsy were not referred for MRI biopsy, which resulted in a higher proportion of lesions assessed as PI-RADS 3. Fourteen lesions suspected of local recurrence were assessed in our study. Cancer was found in approximately 72% of the lesions. Conclusions: Performing prostate biopsy under the guidance of real-time MRI allows precise collection of material for histological examination (even from a very small lesion). As a result, both primary cancer and local recurrence after previous radiotherapy of prostate cancer can be confirmed

Profilaktyka społeczna w rodzinie i szkole: wybrane zagadnienia

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