A deficit of spatial remapping in constructional apraxia after right-hemisphere stroke

This Article is provided by the Brunel Open Access Publising Fund - Copyright @ 2010 Oxford University PressConstructional apraxia refers to the inability of patients to copy accurately drawings or three-dimensional constructions. It is a common disorder after right parietal stroke, often persisting after initial problems such as visuospatial neglect have resolved. However, there has been very little experimental investigation regarding mechanisms that might contribute to the syndrome. Here, we examined whether a key deficit might be failure to integrate visual information correctly from one fixation to the next. Specifically, we tested whether this deficit might concern remapping of spatial locations across saccades. Right-hemisphere stroke patients with constructional apraxia were compared to patients without constructional problems and neurologically healthy controls. Participants judged whether a pattern shifted position (spatial task) or changed in pattern (non-spatial task) across two saccades, compared to a control condition with an equivalent delay but without intervening eye movements. Patients with constructional apraxia were found to be significantly impaired in position judgements with intervening saccades, particularly when the first saccade of the sequence was to the right. The importance of these remapping deficits in constructional apraxia was confirmed through a highly significant correlation between saccade task performance and constructional impairment on standard neuropsychological tasks. A second study revealed that even single saccades to the right can impair constructional apraxia patients’ perception of location shifts. These data are consistent with the view that rightward eye movements result in loss of remembered spatial information from previous fixations, presumably due to constructional apraxia patients’ damage to the right-hemisphere regions involved in remapping locations across saccades. These findings provide the first evidence for a deficit in remapping visual information across saccades underlying right-hemisphere constructional apraxia.European Commission Marie Curie Intra-European Fellowship (011457 to C.R.) and a Wellcome Trust Senior Fellowship (to M.H.)

SHR overexpression induces the formation of supernumerary cell layers with cortex cell identity in rice

The number of root cortex cell layers varies among plants, and many species have several cortical cell layers. We recently demonstrated that the two rice orthologs of the Arabidopsis SHR gene, OsSHR1 and OsSHR2, could complement the A. thaliana shr mutant. Moreover, OsSHR1 and OsSHR2 expression in A. thaliana roots induced the formation of extra root cortical cell layers. In this article, we demonstrate that the overexpression of AtSHR and OsSHR2 in rice roots leads to plants with wide and short roots that contain a high number of extra cortical cell layers. We hypothesize that SHR genes share a conserved function in the control of cortical cell layer division and the number of ground tissue cell layers in land plants

Normative values of the topological metrics of the structural connectome: A multi-site reproducibility study across the Italian Neuroscience network

Purpose: The use of topological metrics to derive quantitative descriptors from structural connectomes is receiving increasing attention but deserves specific studies to investigate their reproducibility and variability in the clinical context. This work exploits the harmonization of diffusion-weighted acquisition for neuroimaging data performed by the Italian Neuroscience and Neurorehabilitation Network initiative to obtain normative values of topological metrics and to investigate their reproducibility and variability across centers. / Methods: Different topological metrics, at global and local level, were calculated on multishell diffusion-weighted data acquired at high-field (e.g. 3 T) Magnetic Resonance Imaging scanners in 13 different centers, following the harmonization of the acquisition protocol, on young and healthy adults. A “traveling brains” dataset acquired on a subgroup of subjects at 3 different centers was also analyzed as reference data. All data were processed following a common processing pipeline that includes data pre-processing, tractography, generation of structural connectomes and calculation of graph-based metrics. The results were evaluated both with statistical analysis of variability and consistency among sites with the traveling brains range. In addition, inter-site reproducibility was assessed in terms of intra-class correlation variability. / Results: The results show an inter-center and inter-subject variability of <10%, except for “clustering coefficient” (variability of 30%). Statistical analysis identifies significant differences among sites, as expected given the wide range of scanners’ hardware. / Conclusions: The results show low variability of connectivity topological metrics across sites running a harmonised protocol

Antimicrobial use and microbiological testing in district general hospital ICUs of the Veneto region of north-east Italy

International - predominantly American - studies undertaken in the ICUs of teaching centres show that inadequate antibiotic therapy increases mortality and length of stay. We sought to ascertain whether this also pertains to smaller ICUs in the Veneto region of north-east Italy. To the best of our knowledge, this is the first such survey in the Veneto area or in Italy as a whole. A retrospective, observational study was performed across five general-hospital ICUs to examine appropriateness of microbiological sampling, empirical antibiotic adequacy, and outcomes. Among 911 patients (mean age, 65.8 years ± 16.2 SD; median ICU stay, 17.0 days [IQR, 8.0–29.0]), 757 (83.1 %) were given empirical antibiotics. Treatment adequacy could be fully assessed in only 212 patients (28.0 %), who received empirical treatment and who had a relevant clinical sample collected at the initiation of this antibiotic (T0). Many other patients only had delayed microbiological investigation of their infections between day 1 and day 10 of therapy. Mortality was significantly higher among the 34.9 % of patients receiving inadequate treatment (48.6 % vs 18.80 %; p < 0.001). Only 32.5 % of combination regimens comprised a broad-spectrum Gram-negative β-lactam plus an anti-MRSA agent, and many combinations were irrational. Inadequate treatment was frequent and was strongly associated with mortality; moreover, there was delayed microbiological investigation of many infections, precluding appropriate treatment modification and de-escalation. Improvements in these aspects and in antibiotic stewardship are being sought

Cultural trauma, counter-narratives, and dialogical intellectuals: the works of Murakami Haruki and Mori Tatsuya in the context of the Aum affair

In this article, we offer a new conceptualization of intellectuals as carriers of cultural trauma through a case study of the Aum Affair, a series of crimes and terrorist attacks committed by the Japanese new religious movement Aum Shinrikyō. In understanding the performative roles intellectuals play in trauma construction, we offer a new dichotomy between “authoritative intellectuals,” who draw on their privileged parcours and status to impose a distinct trauma narrative, and “dialogical intellectuals,” who engage with local actors dialogically to produce polyphonic and open-ended trauma narratives. We identify three dimensions of dialogical intellectual action: firstly, the intellectuals may be involved in dialogue with local participants; secondly, the intellectual products themselves may be dialogical in content; and thirdly, there might be a concerted effort on the part of the intellectuals to record and to disseminate dialogue between local participants. In the context of the Aum Affair, we analyze the works of Murakami Haruki and Mori Tatsuya as dialogical intellectuals while they sought, with the help of local actors’ experiences, to challenge and to alter the orthodox trauma narrative of Aum Shinrikyō as exclusively a social evil external to Japanese society and an enemy to be excluded from it. Towards the end of the article, we discuss the broader significance of this case study and suggest that in light of recent societal and technological developments, the role and scope of dialogical intellectuals as carriers of trauma are changing and possibly expanding

Stereoselective handling of perhexiline:Implications regarding accumulation within the human myocardium

Purpose: Perhexiline is a prophylactic anti-ischaemic agent with weak calcium antagonist effect which has been increasingly utilised in the management of refractory angina. The metabolic clearance of perhexiline is modulated by CYP2D6 metaboliser status and stereoselectivity. The current study sought to (1) determine whether the acute accumulation of perhexiline in the myocardium is stereoselective and (2) investigate the relationship between duration of short-term therapy and the potential stereoselective effects of perhexiline within myocardium. Method: Patients (n = 129) from the active arm of a randomised controlled trial of preoperative perhexiline in cardiac surgery were treated with oral perhexiline for a median of 9 days. Correlates of atrial and ventricular concentrations of enantiomers were sought via univariate followed by multivariate analyses. Results: Myocardial uptake of both (+) and (−) perhexiline was greater in ventricles than in atria, and there was more rapid clearance of (−) than (+) perhexiline. The main determinants of atrial uptake of both (+) and (−) perhexiline were the plasma concentrations [(+) perhexiline: β = −0.256, p = 0.015; (−) perhexiline: β = −0.347, p = 0.001] and patients’ age [(+) perhexiline: β = 0.300, p = 0.004; (−) perhexiline: β = 0.288, p = 0.005]. Atrial uptake of (+) enantiomer also varied directly with duration of therapy (β = 0.228, p = 0.025), while atrial uptake of (−) perhexiline varied inversely with simultaneous heart rate (β = −0.240, p = 0.015). Conclusion: (1) Uptake of both perhexiline enantiomers into atrium is greater with advanced age and displays evidence of both saturability and minor stereoselectivity. (2) Atrial uptake of (−) perhexiline may selectively modulate heart rate reduction

Antibody response elicited by the SARS-CoV-2 vaccine booster in patients with multiple sclerosis: Who gains from it?

Background and purpose: Although two doses of COVID-19 vaccine elicited a protective humoral response in most persons with multiple sclerosis (pwMS), a significant group of them treated with immunosuppressive disease-modifying therapies (DMTs) showed less efficient responses. Methods: This prospective multicenter observational study evaluates differences in immune response after a third vaccine dose in pwMS. Results: Four hundred seventy-three pwMS were analyzed. Compared to untreated patients, there was a 50-fold decrease (95% confidence interval [CI] = 14.3–100.0, p &lt; 0.001) in serum SARS-CoV-2 antibody levels in those on rituximab, a 20-fold decrease (95% CI = 8.3–50.0, p &lt; 0.001) in those on ocrelizumab, and a 2.3-fold decrease (95% CI = 1.2–4.6, p = 0.015) in those on fingolimod. As compared to the antibody levels after the second vaccine dose, patients on the anti-CD20 drugs rituximab and ocrelizumab showed a 2.3-fold lower gain (95% CI = 1.4–3.8, p = 0.001), whereas those on fingolimod showed a 1.7-fold higher gain (95% CI = 1.1–2.7, p = 0.012), compared to patients treated with other DMTs. Conclusions: All pwMS increased their serum SARS-CoV-2 antibody levels after the third vaccine dose. The mean antibody values of patients treated with ocrelizumab/rituximab remained well below the empirical "protective threshold" for risk of infection identified in the CovaXiMS study (&gt;659 binding antibody units/mL), whereas for patients treated with fingolimod this value was significantly closer to the cutoff