Partial dissociation in the neural bases of VSTM and imagery in the early visual cortex

Visual short-term memory (VSTM) and visual imagery are believed to involve overlapping neuronal representations in the early visual cortex. While a number of studies have provided evidence for this overlap, at the behavioral level VSTM and imagery are dissociable processes; this begs the question of how their neuronal mechanisms differ. Here we used transcranial magnetic stimulation (TMS) to examine whether the neural bases of imagery and VSTM maintenance are dissociable in the early visual cortex (EVC). We intentionally used a similar task for VSTM and imagery in order to equate their assessment. We hypothesized that any differential effect of TMS on VSTM and imagery would indicate that their neuronal bases differ at the level of EVC. In the "alone" condition, participants were asked to engage either in VSTM or imagery, whereas in the "concurrent" condition, each trial required both VSTM maintenance and imagery simultaneously. A dissociation between VSTM and imagery was observed for reaction times: TMS slowed down responses for VSTM but not for imagery. The impact of TMS on sensitivity did not differ between VSTM and imagery, but did depend on whether the tasks were carried concurrently or alone. This study shows that neural processes associated with VSTM and imagery in the early visual cortex can be partially dissociated. (C) 2015 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).Peer reviewe

The release of eosinophil chemotactic activity and eosinophil chemokinesis inhibitory activity by mononuclear cells from atopic asthmatic and non-atopic subjects.

The goal of our study was to assess the chemotactic activity for eosinophils (ECA) and neutrophils (NCA) and histamine releasing activity (HRA) in crude supernatants of mononuclear cells in monosensitized atopic asthmatics and healthy controls. Chemotactic activity for ECA and neutrophils was measured in supernatants of cultured mononuclear cells with modified Boyden's chamber and HRA was assessed on healthy donor basophils. With respect to ECA generation two distinct subgroups of subjects were distinguished: releasers [ECA (+)] and non-releasers [ECA (-)]. In atopic and non-atopic ECA (+) the mean ECA index was 3.78 +/- 0.49 and 2.47 +/- 0.27 respectively (P > 0.05). Supernatants from the remaining subjects (seven of 22 atopic and five of 11 non-atopic) did not express ECA, but revealed significant inhibitory activity for chemokinesis of eosinophils (mean chemotactic index 0.25 +/- 0.16 and 0.48 +/- 0.22 for atopic and non-atopic non-releasers respectively). Stimulation with antigen of MNC from atopic and with PHA from non-atopic ECA (-) restored cells ability to release ECA. Sephadex gel chromatography revealed that supernatants of MNC contained chemotactic and chemokinesis inhibitory activity in different fractions. The spontaneous productions of NCA and HRA by mononuclear cells was similar in ECA releasers and non-releasers, although the HRA was higher following stimulation with PHA in the non-atopic ECA (+) subgroup. Our study demonstrated, for the first time, that MNC are capable of generating not only chemotactic activity but also chemokinesis inhibitory activity for eosinophils

Quasi-point separation of variables for the Henon-Heiles system and a system with quartic potential

We examine the problem of integrability of two-dimensional Hamiltonian systems by means of separation of variables. The systematic approach to construction of the special non-pure coordinate separation of variables for certain natural two-dimensional Hamiltonians is presented. The relations with SUSY quantum mechanics are discussed.Comment: 11 pages, Late

Slow dynamics of solid proteins : Nuclear Magnetic Resonance relaxometry versus Dielectric Spectroscopy

Acknowledgement This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 668119 (project “IDentIFY”).Peer reviewedPublisher PD

1H spin-lattice NMR relaxation in the presence of residual dipolar interactions : Dipolar relaxation enhancement

This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 668119 (project “IDentIFY”). The role of COST Action CA15209 (European Network on NMR Relaxometry) is also acknowledged.Peer reviewedPublisher PD

Quantitative methods to monitor RNA biomarkers in myotonic dystrophy

Myotonic dystrophy type 1 (DM1) and type 2 (DM2) are human neuromuscular disorders associated with mutations of simple repetitive sequences in afected genes. The abnormal expansion of CTG repeats in the 3′-UTR of the DMPK gene elicits DM1, whereas elongated CCTG repeats in intron 1 of ZNF9/CNBP triggers DM2. Pathogenesis of both disorders is manifested by nuclear retention of expanded repeat containing RNAs and aberrant alternative splicing. The precise determination of absolute numbers of mutant RNA molecules is important for a better understanding of disease complexity and for accurate evaluation of the efficacy of therapeutic drugs. We present two quantitative methods, Multiplex Ligation-Dependent Probe Amplifcation and droplet digital PCR, for studying the mutant DMPK transcript (DMPKexpRNA) and the aberrant alternative splicing in DM1 and DM2 human tissues and cells. We demonstrate that in DM1, the DMPKexpRNA is detected in higher copy number than its normal counterpart. Moreover, the absolute number of the mutant transcript indicates its low abundance with only a few copies per cell in DM1 fibroblasts. Most importantly, in conjunction with fuorescence in-situ hybridization experiments, our results suggest that in DM1 fibroblasts, the vast majority of nuclear RNA foci consist of a few molecules of DMPKexpRNA

Prevention of HIV infection

W artykule przedstawiono podstawowe zagadnienia służące zapobieganiu rozprzestrzenianiu się wirusa HIV, profilaktykę i programy o charakterze prewencyjnym. Szczegółowiej omówiono czynniki społeczne powodujące podatność na HIV, oraz profilaktykę poekspozycyjną.This article presents basic facts that are helpful in the avoidance of HIV infection and preventive programmes. Social factors triggering susceptibility to HIV as well as post-exposure prophylaxis were discussed in greater detail

Discrimination of papillary thyroid cancer from non-cancerous thyroid tissue based on lipid profiling by mass spectrometry imaging

Introduction: The distinction of papillary thyroid carcinomas from benign thyroid lesions has important implication for clinical management. Classification based on histopathological features can be supported by molecular biomarkers, including lipidomic signatures, identified with the use of high-throughput mass spectrometry techniques. Formalin fixation is a standard procedure for stabilization and preservation of tissue samples, therefore this type of samples constitute highly valuable source of clinical material for retrospective molecular studies. In this study we used mass spectrometry imaging to detect lipids discriminating papillary cancer from not cancerous thyroid directly in formalin-fixed tissue sections. Material and methods: For this purpose imaging and profiling of lipids present in non-malignant and cancerous thyroid tissue specimens were conducted. High resolution MALDI-Q-Ion Mobility-TOF-MS technique was used for lipidomic analysis of formalin fixed thyroid tissue samples. Lipids were identified by the comparison of the exact molecular masses and fragmentation pathways of the protonated molecule ions, recorded during the MS/MS experiments, with LIPID MAPS database. Results: Several phosphatidylcholines (32:0, 32:1, 34:1 and 36:3), sphingomyelins (34:1 and 36:1) and phosphatidic acids (36:2 and 36:3) were detected and their abundances were significantly higher in cancerous tissue compared to non-cancerous tissue. The same lipid species were detected in formalin-fixed as in fresh-frozen tissue, but [M + Na]+ions were the most abundant in formalin fixed whereas [M + K]+ions were predominant in fresh tissue. Conclusions: Our results prove the viability of MALDI-MSI for analysis of lipid distribution directly in formalin-fixed tissue, and the potential for their use in the classification of thyroid diseases

The role of a nurse in the prevention of HIV infection

Zadania stawiane przed pielęgniarkami w zakresie profilaktyki HIV skłaniają do zastanowienia się, w jakim stopniu partnerami w tych działaniach mogą być sami nosiciele wirusa HIV, a także młodzież. Dla wyjaśnienia tych wątpliwości autorzy podjęli badania własne, których celem było określenie stanu wiedzy grup badanych nosicieli wirusa HIV oraz młodzieży gimnazjalnej na temat zakażenia wirusem HIV. Materiał i metody. W badaniach udział wzięło 31 nosicieli wirusa HIV hospitalizowanych w jednym z warszawskich szpitali oraz 58 uczniów I klasy jednego z warszawskich gimnazjów. W badaniu posłużono się metodą sondażu diagnostycznego, techniką była autor-ska ankieta służąca ocenie stanu wiedzy na temat HIV. Wyniki i wnioski. Stan wiedzy na temat zakażenia HIV w grupie nosicieli wirusa jest wysoki, mimo to wymaga jeszcze uzupełnienia wiedzy. Wśród młodzieży natomiast wiedza jest obarczona wieloma mitami i negatywnymi stereotypami, co oznacza, że młodzież wymaga stałej edukacji w kierunku profilaktyki HIV/AIDS.The tasks that are expected of nurses as far as HIV prevention is concerned make one wonder to what degree HIV carriers and youth can partner those tasks. In order to clear those doubts the authors undertaken their self-developed research whose objective was to evaluate the state of knowledge on HIV infection among the interviewed HIV carriers and junior high school students. Materials and methods. 31 HIV carriers hospitalized in one of the hospitals in Warsaw and 58 1st grade students in one of the junior schools in Warsaw took part in the research. The diagnostic poll method was used, the research tool being a self-developed question-naire whose purpose was to assess the level of knowledge on HIV. Results and conclusion. The level of knowledge on HIV infection is high among HIV carriers; nevertheless, their knowledge still needs to be broadened. Among the youth there are many myths and negative stereotypes incorporated in the knowledge, which means that there is a need for constant education of youth on HIV/AIDS prevention