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A comprehensive study of the functioning of antioxidant system in rats with rotenone-induced parkinsonism was conducted. The development of pathology led to inhibition of the majority of the studied antioxidant enzymes in the brain and blood serum of animals, which can be associated with decompensation of oxidative stress under conditions of prolonged mitochondrial dysfunction. These changes apparently make an important contribution into neuronal degeneration in the cerebral cortex and striatum and motor disorders in experimental animals.

Background: Verb and sentence processing impairments are frequently observed in people with aphasia (PWA). However, patterns of impairment (i.e. combinations of deficits that are revealed by arrays of tasks) are usually investigated at the group level, by selecting groups of patients with specific aphasia types (e.g., non-fluent variants with signs of agrammatism), or in case-series with relatively small samples. Aims: We aimed to explore patterns of impairment in verb and sentence processing in a large (N = 54) group of PWA with various aphasia types, using methods that do not require a priori aphasia-type information. Methods & Procedures: To assess verb and sentence processing impairments in production and comprehension, we used the Verb and Sentence Test (VAST) adapted to Russian (VAST-Ru). As our main method, we used k-means cluster analysis to group individuals based on their scores on different tasks of the VAST-Ru. We then compared cluster allocations to aphasia types (according to Alexander Luria’s classification) established by a standard clinical evaluation procedure. As a follow up, we investigated performance of each person with aphasia on each task by comparing their individual scores to the control group. Outcomes & Results: The k-means analysis grouped the PWA into two clusters. The main difference between the clusters was the severity of impairment across most of the tasks, both at the single verb and at the sentence level, both in production and in comprehension. All participants with efferent motor aphasia (roughly corresponding to Broca’s aphasia) and most of the participants with acoustic-mnestic aphasia (roughly corresponding to anomic aphasia) were in the less-impaired cluster. Complex aphasia types (complex motor and complex temporal aphasia) pertained to the more-impaired cluster, while other aphasia types (dynamic aphasia, corresponding to transcortical motor, and sensory, corresponding to Wernicke’s aphasia) were more or less evenly distributed over two clusters. Individual-level analysis revealed heterogeneous patterns of impairment in both clusters and across different aphasia types. Conclusions: These results demonstrate that verb and sentence impairments are prevalent in aphasia, irrespective of the aphasia type. They also indicate that aphasia severity mediates verb and sentence impairment in aphasia. We could not find a clear correspondence between individual patterns of impairment and aphasia type at this stage. The clinical implications are discussed.

A theoretical and experimental study was performed of a frequency dependence of the amplitude-phase characteristics of the vestibular nerve stimulation signal and its changes during passage from the stimulating electrodes to the end of the vestibular nerve. To assess the influence of leakage currents on the change in the stimulating current pulse, a physico-mathematical model of the vestibular organ and electrical processes occurring in its tissues was developed on the basis of experimental data on electrophysical and anatomical characteristics of the vestibular labyrinth tissues by the example of a guinea pig. The calculations and measurements of the frequency dependence of the amplitude-phase characteristics of the stimulating signal at a recording electrode located in the Scarp’s ganglion are performed. It is established that the influence of leakage currents on the signal amplitude at the recording electrode is significant in the entire frequency range considered. Compensation of the influence of leakage currents will improve the stimulating signal quality and increase the transfer function of the vestibular implant.

Almost 70 years ago, Alexander Luria incorporated semantic aphasia among his aphasia classifications by demonstrating that deficits in linking the logical relationships of words in a sentence could co-occur with non-linguistic disorders of calculation, spatial gnosis and praxis deficits. In line with his comprehensive approach to the assessment of language and other cognitive functions, he argued that deficits in understanding semantically reversible sentences and prepositional phrases, for example, were in line with a single neuropsychological factor of impaired spatial analysis and synthesis, since understanding such grammatical relationships would also draw on their spatial relationships. Critically, Luria demonstrated the neural underpinnings of this syndrome with the critical implication of the cortex of the left temporal-parietal-occipital (TPO) junction. In this study, we report neuropsychological and lesion profiles of 10 new cases of semantic aphasia. Modern neuroimaging techniques provide support for the relevance of the left TPO area for semantic aphasia, but also extend Luria's neuroanatomical model by taking into account white matter pathways. Our findings suggest that tracts with parietal connectivity the arcuate fasciculus (long and posterior segments), the inferior fronto-occipital fasciculus, the inferior longitudinal fasciculus, the superior longitudinal fasciculus II and III, and the corpus callosum are implicated in the linguistic and non-linguistic deficits of patients with semantic aphasia. (C) 2016 Elsevier Ltd. All rights reserved.

A growing literature is pointing towards the importance of white matter, tracts in understanding the neural mechanisms of language processing, and determining the nature of language deficits and recovery patterns in aphasia. Measurements extracted from diffusion-weighted (DW) images provide comprehensive in vivo measures of local micro structural properties of fiber pathways. In the current study, we compared microstructural properties of major white matter tracts implicated in language processing in each hemisphere (these included arcuate fasciculus (AF), superior longitudinal fasciculus (SLF), inferior longitudinal fasciculus (ILF), inferior frontal-occipital fasciculus (IFOF), uncinate fasciculus (UF), and corpus callosum (CC), and corticospinal tract (CST) for control purposes) between individuals with aphasia and healthy controls and investigated the relationship between these neural indices and language deficits.Thirty-seven individuals with aphasia due to left hemisphere stroke and eleven age matched controls were scanned using DW imaging sequences. Fractional anisotropy (FA), mean diffusivity (MD), radial diffusivity (RD), axial diffusivity (AD) values for each major white matter tract were extracted from DW images using tract masks chosen from standardized atlases. Individuals with aphasia were also assessed with a standardized language test in Russian targeting comprehension and production at the word and sentence level.Individuals with aphasia had significantly lower FA values for left hemisphere tracts and significantly higher values of MD, RD and AD for both left and right hemisphere tracts compared to controls, all indicating profound impairment in tract integrity. Language comprehension was predominantly related to integrity of the left IFOF and left ILF, while language production was mainly related to integrity of the left AF. In addition, individual segments of these three tracts were differentially associated with language production and comprehension in aphasia. Our findings highlight the importance of fiber pathways in supporting different language functions and point to the importance of temporal tracts in language processing, in particular, comprehension. (C) 2016 Elsevier Ltd. All rights reserved.

Despite a persistent interest in verb processing, data on the neural underpinnings of verb retrieval are fragmentary. The present study is the first to analyze the contributions of both grey and white matter damage affecting verb retrieval through action naming in stroke. We used voxel-based lesion-symptom mapping (VLSM) with an action naming task in 40 left-hemisphere stroke patients. Within the grey matter, we revealed the critical involvement of the left precentral and inferior frontal gyri, insula, and parts of basal ganglia. An overlay of white matter tract probability masks on the VLSM lesion map revealed involvement of left-hemisphere long and short association tracts with terminations in the frontal areas; and several projection tracts. The involvement of these structures is interpreted in the light of existing picture naming models, semantic control processes, and the embodiment cognition framework. Our results stress the importance of both cortico-cortical and cortico-sub-cortical networks of language processing.

Aim. To study gender and age characteristics of incidence rate, mortality and lethality in acute coronary heart disease (ACHD). Material and Methods. Analysis of the ACHD (ICD-10 codes: I21.0-I22.9, I20.0, I24) morbidity, mortality and lethality, depending on sex and age was performed in the population (n=285 736; 46% men) of several city administrative districts of Voronezh, Ryazan and Khanty-Mansiysk. Morbidity, mortality and lethality were calculated on the basis of medical documentation as well as cases identified by the study protocol. Results. The ACHD morbidity and mortality in men were 1.99 and 1.79 times higher (p

In this work, the clinical significance of changes in the activity of adenosine deaminase (ADA) and the content of polyamines in the blood plasma of cats with breast cancer was studied. There were examined 30 cats aged 1 to 20 years, operated on in veterinary clinics due to spontaneous neoplasms. Histological studies of surgical material were performed to establish nosological forms of the tumor. The results of the measurements showed that there were no significant differences between ADA activity in the blood plasma of cats diagnosed with invasive non-specific carcinoma and ADA activity in the blood of healthy animals. In the plasma of animals diagnosed with fibroadenomatous breast hyperplasia, ADA activity was reduced by 35% compared with the control group. The content of putrescine in the red blood cells of cats with benign neoplasms of the mammary gland (fibroepithelial hyperplasia) was statistically significantly increased 5 times compared with the control group. In malignant neoplasms of the mammary gland (invasive non-specific carcinoma, tubular cancer and fibrosarcoma), the content of putrescine and spermine in the blood significantly exceeded the control values by 60 and 10 times, respectively, compared with the control group. Thus, the data obtained indicate the possibility of using polyamines in order to improve the accuracy of diagnosis and treatment of cats with breast cancer. The determination of ADA activity in the blood plasma of cats with breast tumors in the early stages of cancer is not an informationally significant indicator as a tumor biomarker.

Percutaneous coronary intervention (PCI), as a method of myocardial revascularisation, is widely and effectively used for the treatment of coronary heart disease (CHD), with immediate success rates of >90%. Depending on the diagnostic criteria, 5–30% of these patients could develop the signs of periprocedural myocardial damage (PMD) or periprocedural myocardial infarction (PMI). PMD predictors, mechanisms of PMD development, and its specific clinical features play an important role in the PMI prevention. At present, there is no universal agreement on the definition and diagnostics of periprocedural myocardial necrosis and PMI, or on their impact on the clinical outcomes. According to the results of the recent studies, which are presented in this review, the current criteria of PMI might need to be modified, due to the increasingly high sensitivity of the modern threshold levels of troponin.

Effects of Ca2+ ions on the intensity of lipid peroxidation, activities of guaiacol peroxidase, superoxide dismutase (SOD), and catalase, as well as on heat resistance of winter wheat (Triticum aestivium L.) coleoptiles were examined. A preliminary incubation of coleoptile segments in a 5 mM CaCl2 solution was shown to improve their survival rates after an injuring heat treatment (43.5°C). The effect of Ca2+ was suppressed by the inhibitor of Ca2+ channels (1 mM LaCl3). An incubation of coleoptiles in the presence of 5 mM CaCl2 prior to the stress treatment elevated the content of lipid peroxidation product, malondialdehyde (MDA) and stimulated the activities of guaiacol peroxidase, SOD, and catalase. After the heat exposure of untreated and Ca2+-treated seedlings, differential changes in MDA content and in activities of guaiacol peroxidase, SOD, and catalase were observed. It is concluded that a short-term oxidative stress arising in Ca2+-enriched plant tissues after the heat treatment is unrelated to their irreversible damage.

There is a lack of modern quantitative language assessment tests in Russian, integrating neuropsychological and psychometric traditions, and allowing to specify the type and severity of linguistic deficits in individuals with different aphasia profiles. In response to these clinical and research needs, a novel standardized aphasia test – the Russian Aphasia Test (RAT) – is currently being developed. The principal novelty of this test is that each subtest corresponds to a specific level of linguistic processing in one of the four language domains: auditory comprehension, oral production, reading, and writing. In selection of specific tasks for each level of processing we took into account the structure and materials of contemporary standardized aphasia tests in other languages (e.g., Comprehension Aphasia Test, Howard et al., 2010; Psycholinguistic Assessment of Language Processing in Aphasia, Kay et al., 1996), as well as modern (psycho)linguistics theories, and the structural and phonetic specifics of the Russian language. Here we present data on preliminary standardization of auditory comprehension subtests that included the following tasks: • Phonemic – judgment of minimal pairs of nonwords (n=100) and words (n=72). The following factors were taken into account in the design of the subtest: phoneme manner and place of articulation, syllabic structure and position, frequency and imageability (for words). • Lexical – lexical decision (n=120). Lexical frequency, word length, and the degree of similarity of non-words to real words were taken into account. • Lexical-semantic processing – word to picture matching for objects (n=67) and actions (n=68). Items were selected based on naming and image agreement. • Syntactic – sentence to picture matching for various syntactic constructions (n=68), including reversible passives, subject and object clefts, and prepositional phrases. • Discourse – comprehension of orally presented stories of varying lexical-semantic and syntactic difficulty indexed by response accuracy to a set of 16 yes-no questions on explicit and implicit content of the stories. Each subtest was completed by at least 20 individuals with aphasia and 20 healthy age-matched controls. To maximize validity and reliability of the subtests, “poor” items were removed according to the following principles. First, items that were answered erroneously by two or more healthy participants were eliminated. Second, based on item difficulty and corrected-item-total correlation derived for the aphasia group, most sensitive and valid items were retained. Also, it was ensured that each influential psychometric property was represented in the refined set by a wide range of values. Thus, a final smaller set of items for each subtest was selected for further norming and standardization. We will discuss in detail the various conceptual and psychometric considerations that went into the design of the subtests and affected item selection. This project is supported by Russian Scientific Foundation for Humanities, grant №14-04-00596.

Introduction Deficits in working memory (WM) are amongst the most widely acknowledged cognitive impairments in aphasia.However, there is still on-going debate what tasks should be used to assess WM in aphasia (Wright & Fergadiotos, 2012). The two main alternatives for this purpose are simplified complex span tasks and N-back tasks. In a typical complex span task, a processing task (e.g., sentence reading), is given along with a set of stimuli (e.g., words) to be remembered for later recall. In N-back tasks, participants are instructed to judge whether an item matches a previous one presented n items before. Proponents of complex span tasks state that these tasks are the gold standard for assessing WM capacity in cognitive psychology and that variations of these tasksare endorsed as valid means of indexing WM capacity within different theoretical frameworks. On the other hand, researchers using N-back tasks state that since these tasks are more language-free in nature, they are more appropriate for indexing cognitive non-linguistic abilities with language-impaired populations. Several investigations comparing the two tasks in healthy controls have demonstrated no relationship between the two tasks (Jaeggi et al., 2010; Kane et al., 2007). Although, limited conflicting findings indicating a significant relationship between the two tasks have also been reported (Schmiedek et al., 2009). Additionally, performance on complex span task in aphasia studies have repeatedly been related to performance on standardized language tests (Sung et al. 2009; Wright & Fergadiotos, 2012), while similar correlations have never found for N-back tasks (Christensen, & Wright, 2010; Mayer & Murray, 2012). The aim of the present study was to directly investigate the relationship between performance on complex span tasks and N-back tasks in aphasia. Methods 32native speakers of Russian with aphasia following left hemisphere stroke participated. Complex span task (modified listening span task, Ivanova & Hallowell, 2014), 2-back and 0-back tasks with words, a test of auditory language comprehension– Quantitative Assessment of Speech in Aphasia (QASA; Tsvetkova et al., 1981) – were administered. Results and discussion No significant correlations were observed between performance on complex span task and N-back tasks.Furthermore, performance on the modified listening span was related to performance on the comprehension subtest of the QASA, while no relationship was found for 2-back and 0-back tasks.Our results mirror studies in healthy controls that demonstrated no relationship between performance on the two tasks(Jaeggi et al., 2010; Kane et al., 2007). Thus although N-back tasks seem similar to traditional complex span measures and may also index abilities related to cognitive processing, the evidence to date does not warrant their direct association with the construct of WM. Implications for future investigation of cognitive deficits in aphasia will be discussed.