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Previous studies report that acquired prosopagnosia is frequently associated with topographic disorientation. Whether this is associated with a specific anatomic subtype of prosopagnosia, how frequently it is seen with the developmental variant, and what specific topographic function is impaired to account for this problem are not known. We studied ten subjects with acquired prosopagnosia from either occipitotemporal or anterior temporal (AT) lesions and seven with developmental prosopagnosia. Subjects were given a battery of topographic tests, including house and scene recognition, the road map test, a test of cognitive map formation, and a standardized self-report questionnaire. House and/or scene recognition were frequently impaired after either occipitotemporal or AT lesions in acquired prosopagnosia. Subjects with occipitotemporal lesions were also impaired in cognitive map formation: an overlap analysis identified right fusiform and parahippocampal gyri as a likely correlate. Only one subject with acquired prosopagnosia had mild difficulty with directional orientation on the road map test. Only one subject with developmental prosopagnosia had difficulty with cognitive map formation, and none were impaired on the other tests. Scores for house and scene recognition correlated most strongly with the results of the questionnaire. We conclude that topographic disorientation in acquired prosopagnosia reflects impaired place recognition, with a contribution from poor cognitive map formation when there is occipitotemporal damage. Topographic impairments are less frequent in developmental prosopagnosia., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Schizophrenia is associated with deficits in face perception and emotion recognition. Despite consistent behavioural results, the neural mechanisms underlying these cognitive abilities have been difficult to isolate, in part due to differences in neuroimaging methods used between studies for identifying regions in the face processing system. Given this problem, we aimed to validate a recently developed fMRI-based dynamic functional localizer task for use in studies of psychiatric populations and specifically schizophrenia. Previously, this functional localizer successfully identified each of the core face processing regions (i.e. fusiform face area, occipital face area, superior temporal sulcus), and regions within an extended system (e.g. amygdala) in healthy individuals. In this study, we tested the functional localizer success rate in 27 schizophrenia patients and in 24 community controls. Overall, the core face processing regions were localized equally between both the schizophrenia and control group. Additionally, the amygdala, a candidate brain region from the extended system, was identified in nearly half the participants from both groups. These results indicate the effectiveness of a dynamic functional localizer at identifying regions of interest associated with face perception and emotion recognition in schizophrenia. The use of dynamic functional localizers may help standardize the investigation of the facial and emotion processing system in this and other clinical populations., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)

The intraparietal sulcus (IPS) is recruited during tasks requiring attention, maintenance and manipulation of information in working memory (WM). While WM tasks often show broad bilateral engagement along the IPS, topographic maps of contralateral (CL) visual space have been identified along the IPS, similar to retinotopic maps in visual cortex. In the present study, we asked how these visuotopic IPS regions are differentially involved in the maintenance and manipulation of spatial information in WM. Visuotopic mapping was performed in 26 participants to define regions of interest along the IPS, corresponding to previously described IPS0-4. In a separate task, we showed that while maintaining the location of a briefly flashed target in WM preferentially engaged CL IPS, manipulation of spatial information by mentally rotating the target around a circle engaged bilateral IPS, peaking in IPS1 in most participants. Functional connectivity analyses showed increased interaction between the IPS and prefrontal regions during manipulation, as well as interhemispheric interactions. Two control tasks demonstrated that covert attention shifts, and nonspatial manipulation (arithmetic), engaged patterns of IPS activation and connectivity that were distinct from WM manipulation. These findings add to our understanding of the role of IPS in spatial WM maintenance and manipulation., (© The Author 2013. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.)

Background: There is no consensus on the optimal perioperative antibiotic prophylaxis regimen for renal transplant recipients. Some studies have reported that irrigation of the wound at the time of closure without systemic antibiotics may suffice to minimize the risk for surgical site infection (SSI), but many centers still use long-term, multidose regimens in which antibiotics are administered until removal of foreign bodies occur, such as the urethral catheter, drain and central line., Methods: We designed a prospective, randomized, multicenter, controlled trial to compare a single dose versus a multidose regimen of systemic antibiotic prophylaxis in adult, nondiabetic, non-morbidly obese patients undergoing renal transplantation. The primary endpoint was the incidence of SSI; the assessment of other infection in the first postoperative month was the secondary endpoint., Results: Two hundred five patients were enrolled and randomized to receive either a single (n = 103) or multidose antibiotic regimen (n = 102) for prophylaxis. The incidences of SSI and urinary tract infection were similar in both groups., Conclusion: As the dramatic increase in antibiotic resistance has mandated the implementation of global programs to optimize the use of antibiotic agents in humans, we believe that the single dose regimen is preferred, at least in nondiabetic, non-morbidly obese, adult renal transplant recipients., (Copyright © 2015 Elsevier Inc. All rights reserved.)

While the widely studied allocentric spatial representation holds a special status in neuroscience research, its exact nature and neural underpinnings continue to be the topic of debate, particularly in humans. Here, based on a review of human behavioral research, we argue that allocentric representations do not provide the kind of map-like, metric representation one might expect based on past theoretical work. Instead, we suggest that almost all tasks used in past studies involve a combination of egocentric and allocentric representation, complicating both the investigation of the cognitive basis of an allocentric representation and the task of identifying a brain region specifically dedicated to it. Indeed, as we discuss in detail, past studies suggest numerous brain regions important to allocentric spatial memory in addition to the hippocampus, including parahippocampal, retrosplenial, and prefrontal cortices. We thus argue that although allocentric computations will often require the hippocampus, particularly those involving extracting details across temporally specific routes, the hippocampus is not necessary for all allocentric computations. We instead suggest that a non-aggregate network process involving multiple interacting brain areas, including hippocampus and extra-hippocampal areas such as parahippocampal, retrosplenial, prefrontal, and parietal cortices, better characterizes the neural basis of spatial representation during navigation. According to this model, an allocentric representation does not emerge from the computations of a single brain region (i.e., hippocampus) nor is it readily decomposable into additive computations performed by separate brain regions. Instead, an allocentric representation emerges from computations partially shared across numerous interacting brain regions. We discuss our non-aggregate network model in light of existing data and provide several key predictions for future experiments.

We report the case of bilateral renal clear cell carcinoma in the native kidney, occurring fouryears after renal transplantation. Renal Doppler duplex sonography revealed large solid bilateral neoformation. Total-body computed tomography confirmed the presence of bilateral kidney lesions and also showed the presence of concomitant gross dyscariocinetic lesion of left hemotorax. The patient underwent bilateral native nephrectomy and the histological diagnosis was renal cell carcinoma. Subsequent left upper lobectomy revealed necrotic keratinizing squamous cell carcinoma. Then, the patients was switched tacrolimus to everolimus treatment and mycophenolate mofetil was reduced.

The long-term effects of cannabis on human cognition are still unclear, but, considering that cannabis is a widely used substance and, overall, its potential use in therapeutic interventions, it is important to evaluate them. We hypothesize that the discrepancies among studies could be attributed to the specific cognitive function investigated and that skills subserved by the hippocampus, such as the spatial orientation abilities and, specifically, the ability to form and use cognitive maps, should be more compromised than others. Indeed it has been showed that cannabis users have a reduced hippocampus and that the hippocampus is the brain region in which cannabis has the greatest effect since it contains the highest concentration of cannabinoid receptors. To test this hypothesis we asked 15 heavy cannabis users and 19 nonusers to perform a virtual navigational test, the CMT, that assesses the ability to form and use cognitive maps. We found that using cannabis has no effect on these hippocampus-dependent orientation skills. We discuss the implications of our findings and how they relate to evidence reported in the literature that the intervention of functional reorganization mechanisms in cannabis user allows them to cope with the cognitive demands of navigational tasks.

Whether a single perceptual process or separate and possibly independent processes support facial identity and expression recognition is unclear. We used a morphed-face discrimination test to examine sensitivity to facial expression and identity information in patients with occipital or temporal lobe damage, and structural and functional MRI to correlate behavioral deficits with damage to the core regions of the face-processing network. We found selective impairments of identity perception in two patients with right inferotemporal lesions and two prosopagnosic patients with damage limited to the anterior temporal lobes. Of these four patients one exhibited damage to the right fusiform and occipital face areas, while the remaining three showed sparing of these regions. Thus impaired identity perception can occur with damage not only to the fusiform and occipital face areas, but also to other medial occipitotemporal structures that likely form part of a face recognition network. Impaired expression perception was seen in the fifth patient with damage affecting the face-related portion of the posterior superior temporal sulcus. This subject also had difficulty in discriminating identity when irrelevant variations in expression needed to be discounted. These neuropsychological and neuroimaging data provide evidence to complement models which address the separation of expression and identity perception within the face-processing network., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

A variety of lesions in different cerebral regions may affect the human ability to orient in the environment, resulting in 'topographical disorientation'. In a recent study, we documented the first case of Developmental Topographical Disorientation (DTD), in a person with a life-long inability to orient despite otherwise well-preserved cognitive functions, and in the absence of a cerebral injury/malformation or other neurological condition. This selective topographical disorientation was due to her inability to form a 'cognitive map', a mental representation of the environment, which in turn impaired her ability to orient in both familiar and unfamiliar surroundings. Here, we describe 120 new cases of DTD recruited via the internet and assessed with an online battery testing their cognitive and orientation skills. We found that people with DTD differ from matched (age, gender and education) healthy controls only in those skills confined to the orientation/navigation domain, among which the ability to form a cognitive map was the most significant factor that distinguished a person affected by DTD from control subjects.

The recognition of facial identity and expression are distinct tasks, with current models hypothesizing anatomic segregation of processing within a face-processing network. Using fMRI adaptation and a region-of-interest approach, we assessed how the perception of identity and expression changes in morphed stimuli affected the signal within this network, by contrasting (a) changes that crossed categorical boundaries of identity or expression with those that did not, and (b) changes that subjects perceived as causing identity or expression to change, versus changes that they perceived as not affecting the category of identity or expression. The occipital face area (OFA) was sensitive to any structural change in a face, whether it was identity or expression, but its signal did not correlate with whether subjects perceived a change or not. Both the fusiform face area (FFA) and the posterior superior temporal sulcus (pSTS) showed release from adaptation when subjects perceived a change in either identity or expression, although in the pSTS this effect only occurred when subjects were explicitly attending to expression. The middle superior temporal sulcus (mSTS) showed release from adaptation for expression only, and the precuneus for identity only. The data support models where the OFA is involved in the early perception of facial structure. However, evidence for a functional overlap in the FFA and pSTS, with both identity and expression signals in both areas, argues against a complete independence of identity and expression processing in these regions of the core face-processing network.

Topographical disorientation is the inability to orient within the environment, usually acquired from lesions to different cerebral regions participating in the attentional, perceptual or memory functions involved during navigation. We present the first case of a patient with topographical disorientation in the absence of any structural lesion and with intact sensory and intellectual function. Experimental tests in both real and virtual environments revealed a selective impairment in forming a mental representation of the environment, namely a cognitive map. Consistent with the patient's behavioural findings, a functional magnetic resonance imaging (fMRI) study showed lack of activation in the hippocampal complex and the retrosplenial cortex while forming a cognitive map of the environment. Although the lack of neural activity results in a negative finding that generally has low interpretative value, in this specific case our findings may provide useful information. First, in a group of healthy control subjects performing the same task, activity within the hippocampal complex and retrosplenial cortex were detected in each individual participant. Second, we found that within the same regions (showing lack of neural activity while forming a cognitive map of the environment) increased neural activity was detected while the patient was performing a different navigation task. This case is the first evidence reported in the literature showing that topographical disorientation may occur as a developmental defect causing a lifelong disorder affecting daily activities.

The Er:YAG laser has an active medium of Yttrium-Aluminium-Garnet doped with Erbium ions and emits free-running pulsed laser energy at a wavelength of 2940 nm. The Er,Cr:YSGG laser has an active medium of Yttrium-Scandium-Gallium-Garnet doped with Erbium and Chromium ions and emits free-running pulsed laser energy at a wavelength of 2780 nm. These wavelengths have a high absorption in water, which makes their application appropriate for ablating oral soft tissue as well as dental hard tissue. This article examines the principles of use for the Er:YAG and Er,Cr:YSGG lasers in clinical restorative dentistry and reviews the literature regarding different aspects of the use of laser energy on hard tissues.

Face perception is a function with significant complexity, reflected in cognitive models that propose a hierarchy of parallel and serial processing stages. Current neuroimaging data also show that face perception involves a core processing network of cortical modules, which are likely specialized for different functions involved in face processing. The core face processing network is further linked to an extended face processing network which is not solely involved in the perception of faces, but rather contains modules mediating the processing of semantic, biographic and emotional information about people. The segregation of these processes within discrete anatomic regions creates the potential for disconnection between regions to generate neuropsychological deficits involving faces. In this review we consider the types of disconnection possible both within the core face processing system and between the core and extended systems, the pattern of deficits that would be considered as evidence of such disconnections, the potential anatomy of lesions that would create them, and whether any cases exist that meet these criteria.

Despite decades of research, the question of whether the rapid eye movements (REMs) of paradoxical sleep (PS) are equivalent to waking saccades and whether their direction is congruent with visual spatial events in the dream scene is still very controversial. We gained an insight into these questions through the study of a right brain damaged patient suffering attentional neglect for the left side of space and drop of the optokinetic nystagmus (OKN) with alternating rightward slow/leftward fast phases evoked by rightward optic flow. During PS the patient had frequent Nystagmoid REMs with alternating leftward slow/rightward fast phases and reported dreams with visual events evoking corresponding OKN such as a train running leftward. By contrast, just as in waking OKN, Nystagmoid REMs with alternating rightward slow/leftward fast phases were virtually absent. REMs followed by staring eye position or by consecutive REMs were also observed: these showed no asymmetry comparable to that of Nystagmoid ones. The selective disappearance of Nystagmoid REMs in one horizontal direction proves, for the first time, that in humans different types of REMs exists and that these are driven by different premotor mechanisms. Concomitant drop of OKN and Nystagmoid REMs toward the same horizontal direction demonstrates that phylogenetically ancient oculomotor mechanisms, such as the OKN, are shared by waking and PS. On this evidence and converging findings from animal, neuropsychological and brain imaging studies, a new evolutionary account of dream bizarreness is proposed. Classification and labelling of the different types of REMs are also provided.

Our data show that monitoring by sensitive flow cytometric techniques of the de novo production of anti-HLA antibodies in patients receiving kidney transplantation is a useful and noninvasive tool to identify the onset of an immune response towards the graft before any clinical manifestation of antibody-mediated graft injury. Consequently prospective posttransplant monitoring of anti-HLA donor-directed antibodies may offer the chance to realize an effective clinical intervention in order to prevent graft dysfunction and to prolong graft survival. The long follow-up period of the study allowed us to demonstrate a very low graft survival rate in patients who developed donor-specific HLA antibodies in comparison with patients who did not have antibodies, thus confirming the "humoral theory of transplantation". The posttransplant production of anti-HLA antibodies can predict not only graft failure but also chronic dysfunction of the graft. Moreover, our findings suggest that graft survival is influenced by the epitope- and locus-specificity of anti-HLA donor-directed antibodies. The interval between antibody appearance and loss of graft function was short in some patients but reached several years in others. Moreover, some patients showed consistent production of antibodies for many years and an uneventful clinical status. These findings suggest a mechanism of graft "accommodation" or the production of "harmless" antibodies. Immunosuppressive drug combinations able to inhibit T and B cell activation are useful tools to prevent the humoral immune response against graft and consequently to prolong graft survival.