The effect of spaceflight and microgravity on the human brain

peer reviewedMicrogravity, confinement, isolation, and immobilization are just some of the features astronauts have to cope with during space missions. Consequently, long-duration space travel can have detrimental effects on human physiology. Although research has focused on the cardiovascular and musculoskeletal system in particular, the exact impact of spaceflight on the human central nervous system remains to be determined. Previous studies have reported psychological problems, cephalic fluid shifts, neurovestibular problems, and cognitive alterations, but there is paucity in the knowledge of the underlying neural substrates. Previous space analogue studies and preliminary spaceflight studies have shown an involvement of the cerebellum, cortical sensorimotor, and somatosensory areas and the vestibular pathways. Extending this knowledge is crucial, especially in view of long-duration interplanetary missions (e.g., Mars missions) and space tourism. In addition, the acquired insight could be relevant for vestibular patients, patients with neurodegenerative disorders, as well as the elderly population, coping with multisensory deficit syndromes, immobilization, and inactivity

Comparison of the Full Outline of UnResponsiveness and Glasgow Liege Scale/Glasgow Coma Scale in an Intensive Care Unit Population.

peer reviewedBACKGROUND: The Full Outline of UnResponsiveness (FOUR) has been proposed as an alternative for the Glasgow Coma Scale (GCS)/Glasgow Liege Scale (GLS) in the evaluation of consciousness in severely brain-damaged patients. We compared the FOUR and GLS/GCS in intensive care unit patients who were admitted in a comatose state. METHODS: FOUR and GLS evaluations were performed in randomized order in 176 acutely (<1 month) brain-damaged patients. GLS scores were transformed in GCS scores by removing the GLS brainstem component. Inter-rater agreement was assessed in 20% of the studied population (N = 35). A logistic regression analysis adjusted for age, and etiology was performed to assess the link between the studied scores and the outcome 3 months after injury (N = 136). RESULTS: GLS/GCS verbal component was scored 1 in 146 patients, among these 131 were intubated. We found that the inter-rater reliability was good for the FOUR score, the GLS/GCS. FOUR, GLS/GCS total scores predicted functional outcome with and without adjustment for age and etiology. 71 patients were considered as being in a vegetative/unresponsive state based on the GLS/GCS. The FOUR score identified 8 of these 71 patients as being minimally conscious given that these patients showed visual pursuit. CONCLUSIONS: The FOUR score is a valid tool with good inter-rater reliability that is comparable to the GLS/GCS in predicting outcome. It offers the advantage to be performable in intubated patients and to identify non-verbal signs of consciousness by assessing visual pursuit, and hence minimal signs of consciousness (11% in this study), not assessed by GLS/GCS scales

Platinum(II) and Palladium(II) Complexes of Pyridine-2-Carbaldehyde Thiosemicarbazone as Alternative Antiherpes Simplex Virus Agents

The cytotoxicity and the antivirus activity of Pd(II) and Pt(II) complexes with pyridine-2-carbaldehyde thiosemicarbazone (HFoTsc) against HSV replication were evaluated on four HSV strains—two wt strains Victoria (HSV-1) and BJA (HSV-2) and two ACVR mutants with different tk gene mutations R-100 (TKA, HSV-1) and PU (TKN, HSV-2). The experiments were performed on continuous MDBK cells and four HSV 1 and HSV 2 strains were used, two sensitive to acyclovir and two resistant mutants. The five complexes of HFoTsc, [Pt(FoTsc)Cl], [Pt(FoTsc)(H2FoTsc)]Cl2, [Pt(FoTsc)2], [Pd(FoTsc)(H2FoTsc)]Cl2, and [Pd(FoTsc)2], were found to be effective inhibitors of HSV replication. The most promising, active, and selective anti-HSV agent was found to be complex [Pt(FoTsc)(H2FoTsc)]Cl2. This complex could be useful in the treatment of HSV infections, since it is resistant to ACV mutants. PCR study of immediate early 300 bp ReIV Us1 region reveals that the complex [Pt(FoTsc)(H2FoTsc)]Cl2 specifically suppressed wt HSV-1 genome 2 hours after the infection, not inducing apoptosis/necrosis on the 8 hours after virus infection. The target was found to be most probably the viral, instead of the host cell DNA

Instructional leadership in centralised systems: evidence from Greek high-performing secondary schools

This paper examines the enactment of instructional leadership (IL) in high-performing secondary schools (HPSS), and the relationship between leadership and learning in raising student outcomes and encouraging teachers’ professional learning in the highly centralised context of Greece. It reports part of a comparative research study focused on whether, and to what extent, IL has been embraced by Greek school leaders. The study is exploratory, using a qualitative multiple case design to examine two HPSS in Athens. The research design involved a qualitative approach using several different methods, including semi-structured interviews with school principals, deputy heads, subject teachers and subject advisers, plus observation of leadership practice and meetings and scrutiny of relevant policy documents. The findings show that IL is conceptualised as an informal collaborative leadership practice, interwoven with the official multi-dimension role of Greek principals and their ‘semi-IL’ role. In the absence of official IL ‘actors’, teachers’ leadership has been expanding

ANALYSIS OF PRIESTLEY-TAYLOR METHOD FOR THE ASSESSMENT OF REFERENCE EVAPOTRANSPIRATION IN GREECE

Στόχος της εργασίας είναι η εύρεση του εποχιακού σφάλματος στην εκτίμηση της εξατμισοδιαπνοής καλλιέργειας αναφοράς ΕΤο με τη μέθοδο Priestley-Taylor (P-T) και ο επαναπροσδιορισμός του συντελεστή μεταγωγής apt χρησιμοποιώντας τη μέθοδο Penman-Monteith κατά ASCE. Η ανάλυση έγινε για όλο τον ελλαδικό χώρο με χρήση GIS και μέσα μηνιαία κλιματικά δεδομένα της περιόδου 1950-2000. Η ανάλυση σφάλματος για το θερινό εξάμηνο Απριλίου-Σεπτεμβρίου έδειξε ότι η μέθοδος P-T παρουσιάζει αποδεκτές τιμές στο 75.3%, ενώ για το χειμερινό εξάμηνο Οκτωβρίου-Μαρτίου στο 20.2% της ελληνικής επικράτειας. Ο επαναπροσδιορισμός της μέσης τιμής του apt για το χειμερινό και θερινό εξάμηνο έδειξε ότι η χωρική μεταβλητότητά του παρουσιάζει συσχέτιση της τάξεως του ~94% με το έλλειμμα πίεσης κορεσμού υδρατμών. Από την ανάλυση της εποχιακής μεταβολής του συντελεστή apt εκτιμήθηκε η μέση τιμή του σε 1.29 και 1.51 για τη θερινή και χειμερινή περίοδο, αντίστοιχα.The aim of the study is to estimate the seasonal error in the assessment of reference crop evapotranspiration ΕΤο using the Priestley-Taylor (P-T) method and to revise the advection coefficient apt using as a base the ASCE standardized Penman-Monteith method. Analysis was performed for the Greek territory using GIS and gridded data which cover the mean monthly values of climatic parameters for the period 1950-2000. The analysis of seasonal error showed that P-T presents acceptable values in the 73.5% and 20.2% coverage of the greek territory for the dry-warm season (April-September) and the cold-wet season (October-March), respectively. Recalculation of apt for both seasons showed that its spatial variation is described at ~94% level by the vapor pressure deficit. The mean values of apt for the dry-warm season and the cold wet season were found to be 1.29 και 1.51, respectively

Evolutionary aspects of self- and world consciousness in vertebrates

Although most aspects of world and self-consciousness are inherently subjective, neuroscience studies in humans and non-human animals provide correlational and causative indices of specific links between brain activity and representation of the self and the world. In this article we review neuroanatomic, neurophysiological and neuropsychological data supporting the hypothesis that different levels of self and world representation in vertebrates rely upon (i) a \u201cbasal\u201d subcortical system that includes brainstem, hypothalamus and central thalamic nuclei and that may underpin the primary (or anoetic) consciousness likely present in all vertebrates; and (ii) a forebrain system that include the medial and lateral structures of the cerebral hemispheres and may sustain the most sophisticated forms of consciousness [e.g., noetic (knowledge based) and autonoetic, reflective knowledge]. We posit a mutual, bidirectional functional influence between these two major brain circuits. We conclude that basic aspects of consciousness like primary self and core self (based on anoetic and noetic consciousness) are present in many species of vertebrates and that, even self-consciousness (autonoetic consciousness) does not seem to be a prerogative of humans and of some non-human primates but may, to a certain extent, be present in some other mammals and bird

Diorganotin Complexes of a Thiosemicarbazone, Synthesis: Properties, X-Ray Crystal Structure, and Antiproliferative Activity of Diorganotin Complexes

The synthesis and spectral characterization of novel diorganotin complexes with 3-hydroxypyridine-2-carbaldehyde thiosemicarbazone, H(2)L (1), [SnMe(2)(L)] (2), [SnBu(2)(L)] (3), and [SnPh(2)(L)] (4) are reported. The single-crystal X-ray structure of complex [SnPh(2)(L)(DMSO)] (5) shows that the ligand is doubly deprotonated and is coordinated as tridentate ligand. The six coordination number is completed by two carbon atoms of phenyl groups. There are two similar monomers 5a (Sn1) and 5b (Sn51) in the asymmetric unit. The monomers 5a and 5b are linked through intermolecular hydrogen bonds of N-H-O and C-H-S type. C-H -> pi, intermolecular interactions, intra-and intermolecular hydrogen bonds stabilize this structure and leads to aggregation and a supramolecular assembly. The IR and NMR ((1)H, (13)C and (119)Sn) spectroscopic data of the complexes are reported. The in vitro cytotoxic activity has been evaluated against the cells of three human cancer cell lines: MCF-7 (human breast cancer cell line), T-24 (bladder cancer cell line), A-549 (nonsmall cell lung carcinoma) and a mouse L-929 (a fibroblast-like cell line cloned from strain L). Compounds 1, 3, and 4 were found active against all four cell lines. Selectivity was observed for complexes 3 and 4 which were found especially active against MCF-7 and T-24 cancer cell lines.Bioinorg Chem App