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Research evidence has shown that employment is crucial and purposeful for people with intellectual disabilities, promoting positive effects associated with independent living and social inclusion. Notwithstanding, people with intellectual disabilities find it particularly difficult to accomplish successful employment. They face discrimination, and they are considered to lack work capacity. The extremely marginal position of people with intellectual disabilities in the labor market appears to prevail across national settings. Over the last 35 years, there has been an improvement in the vocational inclusion of individuals with intellectual disabilities in Greece, with the legislation embracing the human rights-based approach to disability. Nevertheless, the challenge of accomplishing full participation and equality in employment for people with intellectual disabilities still remains huge in Greece. Their participation rates in the Greek labour market are significantly lower than in the rest of the European Union. This article illustrates the employment provisions for individuals with intellectual disabilities in Greece. Additionally, it presents the current implemented models of their occupational inclusion while critically discussing the convention's pursuance on the Rights of Persons with Disabilities in the Greek context.

Exploring the individual differences of the longitudinal growth of early numeracy (EN) in young children with Intellectual disabilities (IDs) prerequires the critical stage of exploring and validating the potential factor structure. Despite the fact that Relational Skills (RS), Counting Skills (CS) and Operations (O) are expected to constitute distinct domains of EN, there is not sufficient evidence to support either the above position or the position that they are different means of assessing a general-informal numeracy skill construct. This study was designed to shed light in the field through the evaluation of a measurement model describing the structure of RS, CS and O domains of EN and their interrelation. The sample included N = 155 children with IDs, enrolled in special school classes, mentally aged between 5;02 (y;m) and 6;10 (M = 5.11, SD = 0.974). Confirmatory Factor Analysis indicated a “good fit” of the two-factor model (RS, CS + O) of EN in ID (RMSEA=.029

The mitochondrial calcium (Ca2+) uniporter (MCU) channel is responsible for mitochondrial Ca2+ influx. Its expression was found to be upregulated in endothelial cells (ECs) under cardiovascular disease conditions. Since the role of MCU in regulating cytosolic Ca2+ homeostasis in ECs exposed to shear stress (SS) is unknown, we studied mitochondrial Ca2+ dynamics (that is known to decode cytosolic Ca2+ signaling) in sheared ECs. To understand cause-and-effect, we ectopically expressed MCU in ECs. A higher percentage of MCU-transduced ECs exhibited mitochondrial Ca2+ transients/oscillations, and at higher frequency, under SS compared to sheared control ECs. Transients/oscillations correlated with mitochondrial reactive oxygen species (mROS) flashes and mitochondrial membrane potential (ΔΨm) flickers, and depended on activation of the mechanosensitive Piezo1 channel and the endothelial nitric oxide synthase (eNOS). A positive feedback loop composed of mitochondrial Ca2+ uptake/mROS flashes/ΔΨm flickers and endoplasmic reticulum Ca2+ release, in association with Piezo1 and eNOS, provided insights into the mechanism by which SS, under conditions of high MCU activity, may shape vascular EC energetics and function.

The mitochondrial calcium (Ca

Exploring individual differences and looking beyond averaged parameters of early numeracy in young children with mild intellectual disabilities has become an area of interest to many researchers worldwide. This study aimed to identify the different profiles of early numeracy skills in young children with mild intellectual disabilities. For this purpose, we assessed early numeracy through Utrecht early numeracy test and learning aptitude through Detroit Test, in a sample of 135 children diagnosed with intellectual disabilities. The mean of their mental age was 5:09 (years:months) . Two-step cluster analysis identified four homogenous groups of children with distinct early numeracy profiles as follows:C1 were fluent in relational and numerical skills up to 20, C2 were fluent in relational skills and numerical skills up to 10, C3 had basic knowledge of relational skills and inconsistent numerical skills up to 10 and C4 had inconsistent relational skills and numerical skills. Results are discussed with reference to their educational implications.

This study aims to assess reliability and construct validity of the Greek version of the Attitudes Towards Teaching All Students Scale. All teachers were employed either with preschool or first-school-age children. In Study 1, we performed exploratory factor analysis in order to assess the factor structure in a sample of n = 253 in-service teachers. In Study 2, we performed confirmatory factor analysis to confirm the proposed 3-factor structure in a sample of n = 610 in-service teachers. Results suggest that the Greek-adapted version of ATTAS-mm is a reliable and valid research tool and they are discussed in terms of pre-service and in-service teachers’ training.

In the present study, the role of interpersonal coping strategies was examined in relation to teachers’ characteristics and burnout factors. Two hundred sixty-nine General and Special Education tea...

The purpose of this research was to measure teachers and students interpersonal competences in situations that a teacher may face at school and which require interpersonal interaction with students...

High ability preschoolers manifest a great variability on neuropsychological measures and preliteracy skills within their population, despite their intelligence quotient scores in the above average range. The present chapter begins with a definition of the executive functions (EFs), followed by recent research on the penetration of EFs sufficiency or insufficiency in early oral language development. Research data on the EFs and preliteracy skills of high ability preschool children are also presented, followed by the description of an educational EFs training software with embedded preliteracy activities. Its development was based on recent documented evidence on the relevance of early childhood EFs and young children's preliteracy skills. After taking part in a pretest assessment of core EFs and preliteracy skills, a group of 12 high ability preschool children participated in two 30-min sessions of the educational EFs training program with integrated preliteracy activities per week for 12 weeks. Preliminary findings are promising for its efficacy.

Although deaf role model projects have existed for some time and their benefits and outcomes for deaf children/young people and their parents have been recorded, almost no attention has been paid to the experiences of the deaf people who take on these roles. Additionally, the experiences of being a deaf role model have been little explored in the literature. This paper explores available literature on role models for supporting families of deaf children and hearing practitioners. Most deaf people (about 95%), all over the world, have hearing parents and do not meet deaf adults and sign language before the age that formal primary education starts. The majority of hearing parents do not come in touch with deafness even after their child is diagnosed of being deaf. But it’s really crucial for families to have resources that allow them to help their child develop language and have full interaction with their family. Additionally, deaf role models can play a vital role in the development of deaf children’s knowledge, skills, and perceptions. Further work would be also required to understand the longer-term benefits and further developments that deaf role models may wish to initiate. Article visualizations

Calcium (Ca2+) signaling is critical for cell function and cell survival. Mitochondria play a major role in regulating the intracellular Ca2+ concentration ([Ca2+]i). Mitochondrial Ca2+ uptake is an important determinant of cell fate and governs respiration, mitophagy/autophagy, and the mitochondrial pathway of apoptosis. Mitochondrial Ca2+ uptake occurs via the mitochondrial Ca2+ uniporter (MCU) complex. This review summarizes the present knowledge on the function of MCU complex, regulation of MCU channel, and the role of MCU in Ca2+ homeostasis and human disease pathogenesis. The channel core consists of four MCU subunits and essential MCU regulators (EMRE). Regulatory proteins that interact with them include mitochondrial Ca2+ uptake 1/2 (MICU1/2), MCU dominant-negative β-subunit (MCUb), MCU regulator 1 (MCUR1), and solute carrier 25A23 (SLC25A23). In addition to these proteins, cardiolipin, a mitochondrial membrane-specific phospholipid, has been shown to interact with the channel core. The dynamic interplay between the core and regulatory proteins modulates MCU channel activity after sensing local changes in [Ca2+]i, reactive oxygen species, and other environmental factors. Here, we highlight the structural details of the human MCU heteromeric assemblies and their known roles in regulating mitochondrial Ca2+ homeostasis. MCU dysfunction has been shown to alter mitochondrial Ca2+ dynamics, in turn eliciting cell apoptosis. Changes in mitochondrial Ca2+ uptake have been implicated in pathological conditions affecting multiple organs, including the heart, skeletal muscle, and brain. However, our structural and functional knowledge of this vital protein complex remains incomplete, and understanding the precise role for MCU-mediated mitochondrial Ca2+ signaling in disease requires further research efforts.

Empathy is a multi-level phenomenon, referring to the ability of an individual to understand or feel what another experiences. It is a fundamental element of Education, but also of Special and Inclusive education. On the other hand, educational robotics which generally refers to teaching with the utilization of programmable devices, has gained huge momentum nowadays in educational research. This paper aims at highlighting the significance of empathy and empathy training in typical, special and inclusive education. Furthermore, the lack of approaches for active empathy training are highlighted through a brief literature review. This leads to the formation of a new proposal for an Educational Robot which will be used for empathy education via realistic simulations in real classroom settings, mainly in Early Childhood and Primary Education. Indicative lesson plans are be presented.

Some preschool children are at risk for reading difficulties because of inadequate emergent literacy skills. Recent studies have found evidence of the bidirectionality between executive function skills (Efs) and young children's preliteracy skills. This chapter aims to discuss the development and the efficacy of Cogni-Prelit (Cognition and Preliterature) digital application, which stimulates and enhances core Efs integrated with preliteracy activities, in children at risk for reading difficulties. A group of 30 preschool children took part in a pre-test assessment of preliteracy skills and core Efs. Children were then randomly assigned to either an experimental (n =15) or a passive control group (n =15). The experimental group participated in 2 30-min sessions of the Cogni-Prelit training program per week, for 12 weeks. Significant differences between control and experimental groups were observed in the post-test assessment, with the latter performing better on both measures.

Monocytes are critical mediators of the inflammatory response following myocardial infarction (MI) and ischemia-reperfusion injury. They are involved in both initiation and resolution of inflammation and play an integral role in cardiac repair. The antagonistic nature of their function is dependent on their subset heterogeneity and biphasic response following injury. New advancements in single-cell transcriptomics and mass cytometry have allowed us to identify smaller, transcriptionally distinct clusters that may have functional relevance in disease and homeostasis. Additionally, recent insights into the spatiotemporal dynamics of monocytes following ischemic injury and their subsequent interactions with the endothelium and other immune cells reveal a complex interplay between monocytes and the cardiac milieu. In this review, we highlight recent findings on monocyte functional heterogeneity, present new mechanistic insight into monocyte recruitment and fate specification following MI, and discuss promising therapeutic avenues targeting monocytes for the treatment of ischemic heart disease.

Students with learning disabilities often struggle with reading skill acquisition, due to the nature and complexity of the reading process (Brown, 2009). In addition, it has been documented that students experiencing reading disabilities, have problems with the basic cognitive skills of visual perception (Stokes, Matthen & Biggs, 2015). The purpose of the present study was to investigate the role of the cognitive parameters of visual perception, assessed by the Developmental Test of Visual Perception-2nd Edition (DTVP-2, Hammill, Pearson & Voress, 1993) on the reading ability of students with learning disabilities, assessed by Test A (Panteliadou & Antoniou, 2007, Standardized test for reading disabilities in Greek). The sample consisted of 73 children (N=73) attending the 4th and 5th grade of Primary school, diagnosed with learning disability in reading. The results indicated that visual perception was a predictive factor for reading performance. Implications of these findings are discussed in terms of developing early detection programmes as well as effective educational interventions for pre-school and primary school students.

Avoidance of red blood cell (RBC) transfusions in patients awaiting heart transplantation (HTx) has been suggested to minimize the risk of allosensitization. Although recent studies have suggested that an immature immune system in younger HTx recipients may reduce risks associated with RBC transfusion, the role of age in moderating the influence of transfusion on HTx outcomes remains unclear. We used available data from a national transplant registry to explore whether the association between pre-transplant transfusions and outcomes of pediatric HTx varies by patient age. De-identified data were obtained from the United Network for Organ Sharing registry, including first-time recipients of isolated HTx performed at age 0-17 years in 1995-2015. The primary exposure was receiving blood transfusions within 2 weeks prior to HTx. Patient survival after HTx was evaluated using multivariable Cox proportional hazards, where age at transplant was interacted with exposure to pre-transplant transfusion. Age-specific hazard ratios (HRs) of pre-transplant transfusion were plotted across ages at transplant. There were 4883 patients meeting inclusion criteria, of whom 1258 died during follow-up (mean follow-up duration 6 ± 5 years). Patients receiving pre-transplant transfusions were distinguished by younger age, higher prevalence of prior cardiac surgery, greater likelihood of being in the intensive care unit, and greater use of left ventricular assist device bridge to transplant. In multivariable analysis, pre-transplant transfusions were associated with increased mortality hazard among infants

Upon inositol trisphosphate (IP3) stimulation of non-excitable cells, including vascular endothelial cells, calcium (Ca2+) shuttling between the endoplasmic reticulum (ER) and mitochondria, facilitated by complexes called Mitochondria-Associated ER Membranes (MAMs), is known to play an important role in the occurrence of cytosolic Ca2+ concentration ([Ca2+]Cyt) oscillations. A mathematical compartmental closed-cell model of Ca2+ dynamics was developed that accounts for ER-mitochondria Ca2+ microdomains as the µd compartment (besides the cytosol, ER and mitochondria), Ca2+ influx to/efflux from each compartment and Ca2+ buffering. Varying the distribution of functional receptors in MAMs vs. the rest of ER/mitochondrial membranes, a parameter called the channel connectivity coefficient (to the µd), allowed for generation of [Ca2+]Cytoscillations driven by distinct mechanisms at various levels of IP3 stimulation. Oscillations could be initiated by the transient opening of IP3 receptors facing either the cytosol or the µd, and subsequent refilling of the respective compartment by Ca2+ efflux from the ER and/or the mitochondria. Only under conditions where the µd became the oscillation-driving compartment, silencing the Mitochondrial Ca2+ Uniporter led to oscillation inhibition. Thus, the model predicts that alternative mechanisms can yield [Ca2+]Cyt oscillations in non-excitable cells, and, under certain conditions, the ER-mitochondria µd can play a regulatory role.

The purpose of the study was to investigate the relationship between the Test of Detection and Investigation of Attention and Concentration, the Test of Executive Function (Simos et al., 2007a,b) and the Test of Psychosocial Adjustment and Self-Report Scale (Hatzichristou et al., 2007), in a sample of 44 Greek 5th grade students with writing disabilities. The results in our study indicated that there were significant Pearson correlations ranged from 0.39 to 0.43 between cognitive, academic and social factors. Additionally, regression analysis indicated that certain scales of the Test of Attention and Concentration have predictive power to emotional sufficiency (t = 2.001, p < 0.05) and academic self-concept (t = 2.072, p < 0.05). Further implications of these findings for a school-based neuropsychological evaluation and planning of individualized educational interventions are discussed.

Digital Cognitive Games are digital games that promote the performance of high-level cognitive activities involved in Executive functions, namely planning, working memory, attention, inhibition, self-monitoring, self regulation and initiation carried out by prefrontal areas of the frontal lobes. There is evidence that Executive Functions play an important role in learning during childhood. This issue becomes even more critical, when it concerns children with learning difficulties and research upon teaching interventions for enhancing their Executive Functions is carried out over the years. The past decade extremely positive beliefs have emerged regarding the use of Computer-assisted instruction in training Executive Functions. There is a plethora of software, online and mobile applications to claim that they improve the cognitive skills related to the Executive Functions in children and adults. This paper provides an overview of the purposeful approach underlying the utilization of Computer-assisted instruction and more specifically cognitive games in education as well as it presents the currently available online platforms/applications, which address children's population with or without learning difficulties and are supported by conducted scientific research.

Teachers' interpersonal style is a new field of research in the study of students with intellectual disabilities and challenging behaviors in school context. In the present study, we investigate emotions and causal attributions of three basic types of challenging behaviors: aggression, stereotypy, and self-injury, in relation to teachers' interpersonal style. One hundred and seventy seven Greek general and special educator teachers participated in the study by completing a three-scaled questionnaire. Statistical analysis revealed that the type of challenging behaviors affected causal attributions. According to regression analysis, emotions, teaching experience, expertise in special education, and gender explained a significant amount of variance in interpersonal style. Emotions were found to have a mediating role in the relationship between causal attributions and interpersonal style of "willingness to support," when challenging behaviors were attributed to stable causes or causes under the control of the individual with intellectual disabilities.

Written language is a difficult endeavour as the demands of transcription require self-regulatory skills from a motor, cognitive and attention perspective. The purpose of the present study was to investigate the relation between the Test of Writing Difficulties (Porpodas et al., 2007) and the Test of Detection and Investigation of Executive Functions (Simos et al., 2007) in a sample of 50 Greek-speaking, 5th-grade students with writing disabilities. The results of our study indicated that there were significant Pearson correlations ranging from .35 to .44 between executive functions and written expression. Furthermore, regression analysis showed that the subscales of the Test of Executive Functions had significant predictive power for spelling correctness and correction of jumbled sentences. Further implications of these findings for a school-based neuropsychological evaluation and planning of individualised educational interventions are discussed.

Calcium (Ca2+) transport by mitochondria is an important component of the cell Ca2+ homeostasis machinery in metazoans. Ca2+ uptake by mitochondria is a major determinant of bioenergetics and cell fate. Mitochondrial Ca2+ uptake occurs via the mitochondrial Ca2+ uniporter (MCU) complex, an inner mitochondrial membrane protein assembly consisting of the MCU Ca2+ channel, as its core component, and the MCU complex regulatory/auxiliary proteins. In this review, we summarize the current knowledge on the molecular nature of the MCU complex and its regulation by intra- and extramitochondrial levels of divalent ions and reactive oxygen species (ROS). Intracellular Ca2+ concentration ([Ca2+]i), mitochondrial Ca2+ concentration ([Ca2+]m) and mitochondrial ROS (mROS) are intricately coupled in regulating MCU activity. Here, we highlight the contribution of MCU activity to vascular endothelial cell (EC) function. Besides the ionic and oxidant regulation, ECs are continuously exposed to haemodynamic forces (either pulsatile or oscillatory fluid mechanical shear stresses, depending on the precise EC location within the arteries). Thus, we also propose an EC mechanotransduction-mediated regulation of MCU activity in the context of vascular physiology and atherosclerotic vascular disease.

The present study aimed at comparing the working memory of Greek monolingual students to bilingual ones from migrant backgrounds who all attend primary school. Secondly, an effort was made to investigate the correlation of the working memory with the academic performance in both groups. Moreover, the correlation of the vocabulary strategies, employed by monolingual and bilingual students in an integrated memory-based text framework (Rachanioti, Griva & Alevriadou, 2017), with their working memory was explored. The sample consisted of 20 monolingual and 20 bilingual students of Albanian origin, who attended the 5th and 6th grade of three primary schools in Eastern Thessaloniki, Greece. The monolingual and bilingual students were matched according to their mark reports on academic performance. The Automated Working Memory Assessment (Alloway, 2007) was used to assess the students’ working memory. The data revealed that monolingual and bilingual students did not differ either in the verbal working memory or the visuospatial working memory performance. A statistically significant positive correlation between working memory and academic performance was found in both monolingual and bilingual students. The correlation of the Process strategies with the verbal working memory was statistically significant in monolingual students, as well as in the bilingual ones. The Memory strategies were positively correlated with the verbal and visuospatial working memory in both groups. The Confirmation/consolidation strategies were positively correlated with the verbal working memory only in the bilingual students. Results are discussed in terms of memory strategy instruction that may compensate for a poor working memory of both monolingual and bilingual students in a classroom’s setting, thus aiding to improve their academic performance. This study is the first trial of the AWMA in Greek students as well as bilingual immigrant ones.

The aim of this study was to explore the factors that are considered crucial by teachers for a successful intervention in managing of challenging behaviors of people with intellectual disabilities. We asked 177 Greek general and Special Educator teachers to prioritize, using a list of 24 factors, the 6 major that can contribute to the success of an intervention. Teachers chose the factor “knowledge and expertise, staff training” as the most important for the successful management of challenging behaviours. The x 2 test revealed no dependency relationships with teachers’ gender, working structure or Special Education expertise. The need of staff training in changing the way teachers understand challenging behaviors is also discussed.

Over the past few years, perceptions about disability – at least at the theoretical level – have been shifted toward a more progressive approach, which stresses the social aspects of the construction of disability (social model) rather than personal limitations, as supported by the traditional disability approach (medical–individual model). Drawing upon the sociosemiotic approach as developed by Kress and van Leeuwen, the present study examines from a comparative perspective the representations about disability and people with disabilities, as emerging from the drawings produced by 4th grade Greek primary school children. The sample consists of two groups of children. Group A does not share the same school environment with schoolchildren with special education needs, while group B shares the same school surroundings with students attending a special education needs School. The comparative analysis of their drawings indicates that children of both groups reproduce the dominant meanings they receive from th...

The study was designed to determine if spatial location of movement was automatically encoded in memory by children with intellectual disabilities (ID) and typically developing (TD) children. Each participant performed motor exercises at each of four selected locations on a 20X20 m field. The condition variable consisted of intentional position-intentional exercise, incidental position-intentional exercise, and incidental position-incidental exercise. The results indicated that spatial location of movement was not automatically encoded because intention resulted in better performance for TD children. Several critical issues related to intervention strategies in the field of ID are also discussed, considering the educational practices

Several researchers explored the impact of cognition, language and social understanding on theory of mind abilities in typically developing (TD) children and children with intellectual disabilities (ID) (either ID of genetic origin or non-specific ID). The aim of the present study was to determine the specificity of the theory of mind deficit to different groups of children with ID. The results are in accordance with the developmental approach of similar structure hypothesis ( Zigler, 1969 ). The findings are discussed in terms of the specificity of the etiology-related theory of mind profiles of ID groups, considering the educational and social inclusion practices.

Bovine aortic endothelial cells (ECs) respond to nitric oxide (NO) donors by activating the redox-sensitive NF-E2-related factor 2/antioxidant response element pathway and up-regulating heme oxygenase (HO)-1 expression. EC exposure to steady laminar shear stress causes a sustained increase in NO, a transient increase in reactive oxygen species (ROS), and activation of the HO-1 gene. Because steady laminar flow increases the mitochondrial superoxide (\documentclass[10pt]{article} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{pmc} \usepackage[Euler]{upgreek} \pagestyle{empty} \oddsidemargin -1.0in \begin{document} \begin{equation*}{\mathrm{O}}_{2}^{\overline{.}}\end{equation*}\end{document}) production, we hypothesized that mitochondria-derived ROS play a role in shear-induced HO-1 expression. Flow (10 dynes/cm2, 6 h)-induced expression of HO-1 protein was abolished when BAECs were preincubated and sheared in the presence of either NG-nitro-l-arginine methyl ester or N-acetyl-l-cysteine, suggesting that either NO or ROS up-regulates HO-1. Ebselen and diphenylene iodonium blocked HO-1 expression, and uric acid had no effect. The mitochondrial electron transport chain inhibitors, myxothiazol, rotenone, or antimycin A, and the mitochondria-targeted antioxidant peptide, Szeto-Schiller (SS)-31, which scavenges \documentclass[10pt]{article} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{pmc} \usepackage[Euler]{upgreek} \pagestyle{empty} \oddsidemargin -1.0in \begin{document} \begin{equation*}{\mathrm{O}}_{2}^{\overline{.}}\end{equation*}\end{document}, hydrogen peroxide (H2O2), peroxynitrite, and hydroxyl radicals, markedly inhibited the increase in HO-1 expression. These data collectively suggest that mitochondrial H2O2 mediates the HO-1 induction. MitoSOX and 2′,7′-dichlorofluorescin (DCF) fluorescence showed that mitochondrial \documentclass[10pt]{article} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{pmc} \usepackage[Euler]{upgreek} \pagestyle{empty} \oddsidemargin -1.0in \begin{document} \begin{equation*}{\mathrm{O}}_{2}^{\overline{.}}\end{equation*}\end{document} levels and intracellular peroxides, respectively, are higher in sheared ECs compared with static controls and, in part, dependent on NO. SS-31 significantly inhibited both the shear-induced MitoSOX and DCF fluorescence signals. Either phosphatidylinositol 3-kinase or mitogen-activated protein kinase cascade inhibitors blocked the HO-1 induction. In conclusion, under shear, EC mitochondria-derived H2O2 diffuses to the cytosol, where it initiates oxidative signaling leading to HO-1 up-regulation and maintenance of the atheroprotective EC status.

Shear stress is known to stimulate an intracellular free calcium concentration ([Ca2+]i) response in vascular endothelial cells (ECs). [Ca2+]i is a key second messenger for signaling that leads to vasodilation and EC survival. Although it is accepted that the shear-induced [Ca2+]i response is, in part, due to Ca2+ release from the endoplasmic reticulum (ER), the role of mitochondria (second largest Ca2+ store) is unknown. We hypothesized that the mitochondria play a role in regulating [Ca2+]i in sheared ECs. Cultured ECs, loaded with a Ca2+-sensitive fluorophore, were exposed to physiological levels of shear stress. Shear stress elicited [Ca2+]i transients in a percentage of cells with a fraction of them displaying oscillations. Peak magnitudes, percentage of oscillating ECs, and oscillation frequencies depended on the shear level. [Ca2+]i transients/oscillations were present when experiments were conducted in Ca2+-free solution (plus lanthanum) but absent when ECs were treated with a phospholipase C inhibitor, suggesting that the ER inositol 1,4,5-trisphosphate receptor is responsible for the [Ca2+]i response. Either a mitochondrial uncoupler or an electron transport chain inhibitor, but not a mitochondrial ATP synthase inhibitor, prevented the occurrence of transients and especially inhibited the oscillations. Knockdown of the mitochondrial Ca2+ uniporter also inhibited the shear-induced [Ca2+]i transients/oscillations compared with controls. Hence, EC mitochondria, through Ca2+ uptake/release, regulate the temporal profile of shear-induced ER Ca2+ release. [Ca2+]i oscillation frequencies detected were within the range for activation of mechanoresponsive kinases and transcription factors, suggesting that dysfunctional EC mitochondria may contribute to cardiovascular disease by deregulating the shear-induced [Ca2+]i response.

Both in vivo models of ischemia/reperfusion and in vitro models of hypoxia (H)/reoxygenation (R) have demonstrated the crucial role of the Rac1-regulated NADPH oxidase in the production of injurious reactive oxygen species (ROS) by vascular endothelial cells (ECs). Since membrane lipid peroxidation has been established as one of the mechanisms leading to cell death, we examined lipid peroxidation in H/R-exposed cultured human umbilical vein ECs (HUVECs) and the role of Rac1 in this process. H (24 h at 1% O2)/R (5 min) caused an increase in intracellular ROS production compared to a normoxic control, as measured by dichlorofluorescin fluorescence. Nutrient deprivation (ND; 24 h), a component of H, was sufficient to induce a similar increase in ROS under normoxia. Either H(24 h)/R (2 h) or ND (24 h) induced increases in lipid peroxidation of similar magnitude as measured by flow cytometry of diphenyl-1-pyrenylphosphine-loaded HUVECs and Western blotting analysis of 4-hydroxy-2-nonenal-modified proteins in cell lysates. In cells infected with a control adenovirus, H (24 h)/R (2 h) and ND (24 h) resulted in increases in NADPH-dependent superoxide production by 5- and 9-fold, respectively, as measured by lucigenin chemiluminescence. Infection of HUVECs with an adenovirus that encodes the dominant-negative allele of Rac1 (Rac1N17) abolished these increases. Rac1N17 expression also suppressed the H/R- and ND-induced increases in lipid peroxidation. In conclusion, ROS generated via the Rac1-dependent pathway are major contributors to the H/R-induced lipid peroxidation in HUVECs, and ND is able to induce Rac1-dependent ROS production and lipid peroxidation of at least the same magnitude as H/R.

Background Williams (WS) and Down syndromes (DS) are two genetic disorders that involve intellectual disability (ID) and have been extensively studied over the past decades because of the unique linguistic profiles they exhibit. Recent investigations seek to explore the fractionation of linguistic components within the cognitive system using genetically based neurodevelopmental disorders such as WS and DS and to identify different profiles of linguistic function in these two groups of individuals. Method The ‘expressive vocabulary’, ‘receptive vocabulary’, ‘word opposites’ and ‘word definitions’ subtests (Level 1) of the Test of Word Knowledge (TOWK) were used to assess lexical skills in six children with WS and five children with DS. Results Our findings indicate that the two syndromes exhibit substantial differences on linguistic tasks with individuals with WS performing at a higher level compared to those with DS and producing atypical responses in word definitions. The pattern of errors for each syndrome is qualitatively different suggesting that their underlying linguistic mechanisms are distinctive even though ID is similar. Conclusions This study supports the differential outcome of two chromosomal disorders with similar ID. It also argues in favour of the large within group variability of the two syndromes that is not related to mental age but rather to different underlying mechanisms supporting language. These findings are discussed in the light of the current evidence concerning linguistic knowledge of neurodevelopmental and genetic disorders.

The field dependence-independence of normally developing and mentally retarded boys of low and upper/middle socioeconomic status was examined. To test the cognitive style, the 96 young participants were subdivided into four groups ( n = 24 per group) matched on mean mental age, using the Raven Colored Progressive Matrices. Two groups of mentally retarded boys (Groups A and B) and two groups of normally developing boys (Groups C and D). Groups A and C were matched on mental age at 5.6 yr.; Groups B and D were matched on mental age at 7.6 yr. Each pair of groups differed significantly in mean chronological age. Within each subgroup, 12 boys came from upper/middle socioeconomic status families and 12 from low socioeconomic status families. Analysis indicated absence of significant differences between Groups A and C on field dependence-independence, but there were statistically significant differences between Groups B and D. Moreover, analysis showed that boys from families of upper/middle socioeconomic status, both normally developing and mentally retarded, were consistently more field independent than boys from families of low socioeconomic status. Finally, conclusions were drawn concerning the empirical and theoretical benefits for psychology and education, which arise from the study of field dependence-independence of mentally retarded individuals.

Production of reactive oxygen species (ROS) by ischemic tissue after ischemia-reperfusion (I/RP) is an important factor that contributes to tissue injury. The small GTPase Rac1 mediates the oxidative burst, and ROS act on signaling pathways involved in expression of inflammatory genes. Because there is evidence implicating monocytes in the pathogenesis of I/RP injury, our objective was to determine the molecular mechanisms that regulate adhesive interactions between monocytes and hypoxia-reoxygenation (H/RO)-exposed cultured endothelial cells (ECs). When U937 cells were perfused over human umbilical vein ECs at 1 dyn/cm2, H (1 h at 1% O2)/RO (13 h) significantly increased the fluxes of rolling and stably adherent U937 cells. Either EC treatment with the antioxidant pyrrolidine dithiocarbamate (PDTC) or infection with AdRac1N17, which results in expression of the dominant-negative form of Rac1, abolished H/RO-induced ROS production, attenuated rolling, and abolished stable adhesion of U937 cells to H/RO-exposed ECs. Infection with AdRac1N17 also abolished H/RO-induced upregulation of vascular cell adhesion molecule (VCAM)-1. In turn, blocking VCAM-1 abolished U937 cell stable adhesion and slightly increased rolling. We concluded that the Rac1-dependent ROS partially regulate rolling and exclusively regulate stable adhesion of monocytic cells to ECs after H/RO and that stable adhesion, but not rolling, is mediated by ROS-induced expression of VCAM-1.

Calcium (Ca 2+ ) transport by mitochondria is an important component of the cell Ca 2+ homeostasis machinery in metazoans. Ca 2+ uptake by mitochondria is a major determinant of bioenergetics and cell fate. Mitochondrial Ca 2+ uptake occurs via the mitochondrial Ca 2+ uniporter (MCU) complex, an inner mitochondrial membrane protein assembly consisting of the MCU Ca 2+ channel, as its core component, and the MCU complex regulatory/auxiliary proteins. In this review, we summarize the current knowledge on the molecular nature of the MCU complex and its regulation by intra- and extramitochondrial levels of divalent ions and reactive oxygen species (ROS). Intracellular Ca 2+ concentration ([Ca 2+ ] i ), mitochondrial Ca 2+ concentration ([Ca 2+ ] m ) and mitochondrial ROS (mROS) are intricately coupled in regulating MCU activity. Here, we highlight the contribution of MCU activity to vascular endothelial cell (EC) function. Besides the ionic and oxidant regulation, ECs are continuously exposed to haemodynamic forces (either pulsatile or oscillatory fluid mechanical shear stresses, depending on the precise EC location within the arteries). Thus, we also propose an EC mechanotransduction-mediated regulation of MCU activity in the context of vascular physiology and atherosclerotic vascular disease.

During thrombolytic therapy and after recanalization is achieved, reduction in the volume of mural thrombi is desirable. Mural thrombi are known to contribute to rethrombosis and reocclusion. The lysis rate of mural thrombi has been demonstrated to increase with fluid flow in different experimental models, but the mechanisms responsible are unknown. An experimental and a theoretical study were developed to determine the contribution of outer convective transport to the lysis of mural fibrin clots. Normal human plasma containing recombinant tissue-type plasminogen activator (tPA; 0.5 μg/mL) was (re)perfused over mural fibrin clots with fluorescently labeled fibrin at low arterial, arterial, or higher wall shear stresses (4, 18, or 41 dyn/cm2, respectively) and lysis was monitored in real time. Flow accelerated lysis, but significantly only at the highest shear stress: The average lysis front velocity was 3 × 10−5 cm/s at 41 dyn/cm2 vs. almost half of that at the lower shear stresses. Confocal microscopy showed fibrin fibers dissolving only in a narrow region close to the surface when permeation velocity was predicted to be low. A heterogeneous transport-reaction finite element model was used to describe mural fibrinolysis. After scaling the effects of outer and inner convection, inner diffusion, and chemical reactions, a simplified inner diffusion/reaction model was used. Correlation to fibrin lysis data in purified systems dictated higher rates of plasmin(ogen) and tPA adsorption onto fibrin and a decreased catalytic rate of plasmin-mediated fibrin degradation, compared with published parameters. At each shear stress, the model predicted a temporal pattern of lysis of mural fibrin (similar to that observed experimentally), and protease accumulation in a narrow fibrin region and significant lysis inhibition by plasma α2-antiplasmin (according to the literature). Increasing outer convection accelerated mural fibrinolysis, but the model did not predict the big increase in lysis rate at the highest shear stress. At higher than arterial flows, additional mechanisms not accounted for in the current model, such as fibrin collapse at the fibrin front, may regulate the lysis of mural clots and determine the outcome of thrombolytic therapy. © 2002 John Wiley & Sons, Inc. Biotechnol Bioeng 77: 405–419, 2002; DOI 10.1002/bit.10127

The present study aimed at recording and comparing the vocabulary strategies employed by Greek students and bilingual immigrants in an integrated memory-based text framework. Moreover, an effort to correlate the language strategies employed by the participants with their academic performance was attempted. The sample consisted of 20 monolingual and 20 bilingual students of Albanian origin, who attended the 5th and 6th grade of three primary schools in Eastern Thessaloniki, Greece. The monolingual and bilingual students were matched according to their mark reports on academic performance. Qualitative techniques were used for data collection: a) an instrument for recording students' profiles and their difficulties in acquiring vocabulary and memorizing a text b) ‘think aloud’ protocols and retrospective interviews. The identification of the strategies, employed by monolingual and bilingual children in an integrated text framework resulted in the compilation of a strategy model: a) exploration strategies, b) process strategies, c) memory strategies and d) confirmation/consolidation strategies. The correlation of the process strategies with the academic performance was statistically significant in monolingual students, as well as in bilinguals. A stronger positive correlation was found between the memory strategies and the monolinguals’ academic performance, while a positive trend also emerged for bilinguals. Although the study is limited in scope, the strategies resulted from the analysis of the collected data, constitute a holistic process/approach of vocabulary acquisition in an integrated memory-based text framework.

Endothelial cell dysfunction is the hallmark of every cardiovascular disease/condition, including atherosclerosis and ischemia/reperfusion injury. Fluid shear stress acting on the vascular endothelium is known to regulate cell homeostasis. Altered hemodynamics is thought to play a causative role in endothelial dysfunction. The dysfunction is associated with/preceded by mitochondrial oxidative stress. Studies by our group and others have shown that the form and/or function of the mitochondrial network are affected when endothelial cells are exposed to shear stress in the absence or presence of additional physicochemical stimuli. The present review will summarize the current knowledge on the interconnections among intracellular Ca2+ - nitric oxide - mitochondrial reactive oxygen species, mitochondrial fusion/fission, autophagy/mitophagy, and cell apoptosis vs. survival. More specifically, it will list the evidence on potential regulation of the above intracellular species and processes by the fluid shear stress acting on the endothelium under either physiological flow conditions or during reperfusion (following a period of ischemia). Understanding how the local hemodynamics affects mitochondrial physiology and the cell redox state may lead to development of novel therapeutic strategies for prevention or treatment of the endothelial dysfunction and, hence, of cardiovascular disease.

This study compared the weight-discrimination sensitivity of 41 congenitally blind and 41 normally sighted adults. The superior weight-discrimination sensitivity of the congenitally blind subjects suggests that blindness from birth can cause compensatory adaptations within the cutaneous modality.

The Parkinson's disease questionnaire (PDQ-39) is a well-validated British scale for the assessment of health-related quality of life (HQoL) in Parkinson's disease (PD). The PDQ-39 has been translated into Greek and it was applied to 119 Greek PD patients. These patients were classified in stages according to the Hoehn and Yahr (HY) scale and their motor disability was assessed by means of the Unified Parkinson's disease rating scale (UPDRS) as well as the Schwab and England activities of daily living scale (ADL). The Beck depression inventory (BDI) was applied for the evaluation of depression. The translated version of PDQ-39, designated PDQ-39GrV, was validated as follows: (1) Cronbach's α coefficient and item — total Spearman's rank — order correlations were calculated in order to estimate the internal consistency of PDQ-39GrV scales. (2) Validity of the PDQ-39GrV was examined in terms of agreement with the clinical assessment parameters (stage, UPDRS, ADL and BDI scores). (3) Sixty one PD patients were re-evaluated 3–7days later in order to check test-retest reliability. The results showed the following: (1) The PDQ-39GrV demonstrated very good internal consistency (α: 0.71–0.94). Item — total correlations were statistically significant (r: 0.52–0.93). Test-retest measurements correlated significantly (p = 0.001). (2) Clinically obtained motor parameters correlated well with PDQ-39GrV scales influenced by physical aspects of the disease, while emotionally and socially influenced ones correlated with depression. Our findings indicate that PDQ-39 GrV is a reliable, easy to administer scale for the assessment of HQoL in Greek PD patients.