Diagnostics and Rehabilitation of Speech Disorders in Patients with Parkinson's Disease

Статья посвящена актуальному вопросу диагностики и логопедической коррекции речевых нарушений у пациентов нейродегенеративного профиля.The article deals with the topical issue of diagnostics and logopedic treatment of speech disorders in neurodegenerative patients. For people with Parkinson's disease (PD), speech and communication disorders are almost inevitable; they can occur already at the earliest stages of the disease and are sure to progress later on. Patients with PD experience a lack of communication because of speech impairment, which exacerbates depression and affects the quality of life. The aim of the study was to develop a strategy for rehabilitation-pedagogical assistance to people with Parkinson's disease

Mechanisms of gap gene expression canalization in the Drosophila blastoderm

<p>Abstract</p> <p>Background</p> <p>Extensive variation in early gap gene expression in the <it>Drosophila </it>blastoderm is reduced over time because of gap gene cross regulation. This phenomenon is a manifestation of canalization, the ability of an organism to produce a consistent phenotype despite variations in genotype or environment. The canalization of gap gene expression can be understood as arising from the actions of attractors in the gap gene dynamical system.</p> <p>Results</p> <p>In order to better understand the processes of developmental robustness and canalization in the early <it>Drosophila </it>embryo, we investigated the dynamical effects of varying spatial profiles of Bicoid protein concentration on the formation of the expression border of the gap gene <it>hunchback</it>. At several positions on the anterior-posterior axis of the embryo, we analyzed attractors and their basins of attraction in a dynamical model describing expression of four gap genes with the Bicoid concentration profile accounted as a given input in the model equations. This model was tested against a family of Bicoid gradients obtained from individual embryos. These gradients were normalized by two independent methods, which are based on distinct biological hypotheses and provide different magnitudes for Bicoid spatial variability. We showed how the border formation is dictated by the biological initial conditions (the concentration gradient of maternal Hunchback protein) being attracted to specific attracting sets in a local vicinity of the border. Different types of these attracting sets (point attractors or one dimensional attracting manifolds) define several possible mechanisms of border formation. The <it>hunchback </it>border formation is associated with intersection of the spatial gradient of the maternal Hunchback protein and a boundary between the attraction basins of two different point attractors. We demonstrated how the positional variability for <it>hunchback </it>is related to the corresponding variability of the basin boundaries. The observed reduction in variability of the <it>hunchback </it>gene expression can be accounted for by specific geometrical properties of the basin boundaries.</p> <p>Conclusion</p> <p>We clarified the mechanisms of gap gene expression canalization in early <it>Drosophila </it>embryos. These mechanisms were specified in the case of <it>hunchback </it>in well defined terms of the dynamical system theory.</p

Examination and rehabilitation of speech disorders in a patient with subcortical aphasia

The article presents a case of clinical observation of subcortical aphasia. It analyzes the manifestations of speech disorders and disorders of higher mental functions in a patient with a stroke in the basin of the left middle cerebral artery and a hematoma of the left internal carotid artery,В статье рассматриваются проявления речевых расстройств и нарушений высших психических функций у пациентки с инсультом

Comprehensive Screening for COVID-19 at St. Petersburg Oncology Centre

Background. Clinical reports on the coronavirus disease 2019 (COVID-19) suggest its higher incidence and worse outcomes in cancer patients. Considering a rapid pace of the severe acute respiratory syndrome-related coronavirus 2 (SARS-CoV-2) pandemic, more data on the risk of contagion and syndrome course is required with this patient group.Aim. Estimation of the infection rate in cancer patients managed at the Oncology Centre.Materials and methods. This retrospective study included cancer patients managed at the Oncology Centre between 9 April 2020 and 27 May 2020 and routinely tested for SARS-CoV-2 in polymerase chain reaction (PCR) assays and/or COVID-19 in chest computed tomography (CT).Results and discussion. A total of 2,628 patients were included in the study, with 119 (4.5 %) confirmed to have COVID-19; 45/119 were PCR-positive, 95/119 had viral pneumonia in CT, 21/119 were positive for both tests. A total of 47.9 % cases were asymptomatic, 11.8 % revealed a mild single-symptom disease. COVID-19 ended in death in 2 (2.5 %) of 80 cases with a known outcome. In PCR results of both patient and staff screening, the virus detection rate was 3.0 % and 2.4 %, respectively (p = 0.33).Conclusion. A COVID-19 screening revealed no significant difference in the risk of contagion between cancer patients and staff of the Oncology Centre. PCR tests may perform false negative for COVID-19 in cancer patients and should be coupled with CT scanning. The infection is asymptomatic or clinically mild in most other cases

Electron transport in TiO2 probed by THz time-domain spectroscopy

Euan Hendry, F. Wang, J. Shan, T. F. Heinz, and Mischa Bonn, Physical Review B, Vol. 69, article 081101 (2004). "Copyright © 2004 by the American Physical Society."Electron transport in crystalline TiO2 (rutile phase) is investigated by frequency-dependent conductivity measurements using THz time-domain spectroscopy. Transport is limited by electron-phonon coupling, resulting in a strongly temperature-dependent electron-optical phonon scattering rate, with significant anisotropy in the scattering process. The experimental findings can be described by Feynman polaron theory within the intermediate coupling regime and allow for a determination of electron mobility

Gene Circuit Analysis of the Terminal Gap Gene huckebein

The early embryo of Drosophila melanogaster provides a powerful model system to study the role of genes in pattern formation. The gap gene network constitutes the first zygotic regulatory tier in the hierarchy of the segmentation genes involved in specifying the position of body segments. Here, we use an integrative, systems-level approach to investigate the regulatory effect of the terminal gap gene huckebein (hkb) on gap gene expression. We present quantitative expression data for the Hkb protein, which enable us to include hkb in gap gene circuit models. Gap gene circuits are mathematical models of gene networks used as computational tools to extract regulatory information from spatial expression data. This is achieved by fitting the model to gap gene expression patterns, in order to obtain estimates for regulatory parameters which predict a specific network topology. We show how considering variability in the data combined with analysis of parameter determinability significantly improves the biological relevance and consistency of the approach. Our models are in agreement with earlier results, which they extend in two important respects: First, we show that Hkb is involved in the regulation of the posterior hunchback (hb) domain, but does not have any other essential function. Specifically, Hkb is required for the anterior shift in the posterior border of this domain, which is now reproduced correctly in our models. Second, gap gene circuits presented here are able to reproduce mutants of terminal gap genes, while previously published models were unable to reproduce any null mutants correctly. As a consequence, our models now capture the expression dynamics of all posterior gap genes and some variational properties of the system correctly. This is an important step towards a better, quantitative understanding of the developmental and evolutionary dynamics of the gap gene network

Mathematics and biology: a Kantian view on the history of pattern formation theory

Driesch’s statement, made around 1900, that the physics and chemistry of his day were unable to explain self-regulation during embryogenesis was correct and could be extended until the year 1972. The emergence of theories of self-organisation required progress in several areas including chemistry, physics, computing and cybernetics. Two parallel lines of development can be distinguished which both culminated in the early 1970s. Firstly, physicochemical theories of self-organisation arose from theoretical (Lotka 1910–1920) and experimental work (Bray 1920; Belousov 1951) on chemical oscillations. However, this research area gained broader acceptance only after thermodynamics was extended to systems far from equilibrium (1922–1967) and the mechanism of the prime example for a chemical oscillator, the Belousov–Zhabotinski reaction, was deciphered in the early 1970s. Secondly, biological theories of self-organisation were rooted in the intellectual environment of artificial intelligence and cybernetics. Turing wrote his The chemical basis of morphogenesis (1952) after working on the construction of one of the first electronic computers. Likewise, Gierer and Meinhardt’s theory of local activation and lateral inhibition (1972) was influenced by ideas from cybernetics. The Gierer–Meinhardt theory provided an explanation for the first time of both spontaneous formation of spatial order and of self-regulation that proved to be extremely successful in elucidating a wide range of patterning processes. With the advent of developmental genetics in the 1980s, detailed molecular and functional data became available for complex developmental processes, allowing a new generation of data-driven theoretical approaches. Three examples of such approaches will be discussed. The successes and limitations of mathematical pattern formation theory throughout its history suggest a picture of the organism, which has structural similarity to views of the organic world held by the philosopher Immanuel Kant at the end of the eighteenth century