I.J. Namer

Enhanced-reality video fluorescence: a real-time assessment of intestinal viability.

Objective:Our aim was to evaluate a fluorescence-based enhanced-reality system to assess intestinal viability in a laparoscopic mesenteric ischemia model. Materials and Methods:A small bowel loop was exposed, and 3 to 4 mesenteric vessels were clipped in 6 pigs. Indocyanine green (ICG) was administered intravenously 15 minutes later. The bowel was illuminated with an incoherent light source laparoscope (D-light-P, KarlStorz). The ICG fluorescence signal was analyzed with Ad Hoc imaging software (VR-RENDER), which provides a digital perfusion cartography that was superimposed to the intraoperative laparoscopic image [augmented reality (AR) synthesis]. Five regions of interest (ROIs) were marked under AR guidance (1, 2a-2b, 3a-3b corresponding to the ischemic, marginal, and vascularized zones, respectively). One hour later, capillary blood samples were obtained by puncturing the bowel serosa at the identified ROIs and lactates were measured using the EDGE analyzer. A surgical biopsy of each intestinal ROI was sent for mitochondrial respiratory rate assessment and for metabolites quantification. Results:Mean capillary lactate levels were 3.98 (SD = 1.91) versus 1.05 (SD = 0.46) versus 0.74 (SD = 0.34) mmol/L at ROI 1 versus 2a-2b (P = 0.0001) versus 3a-3b (P = 0.0001), respectively. Mean maximal mitochondrial respiratory rate was 104.4 (±21.58) pmolO2/second/mg at the ROI 1 versus 191.1 ± 14.48 (2b, P = 0.03) versus 180.4 ± 16.71 (3a, P = 0.02) versus 199.2 ± 25.21 (3b, P = 0.02). Alanine, choline, ethanolamine, glucose, lactate, myoinositol, phosphocholine, sylloinositol, and valine showed statistically significant different concentrations between ischemic and nonischemic segments. Conclusions:Fluorescence-based AR may effectively detect the boundary between the ischemic and the vascularized zones in this experimental model.

Toward improved grading of malignancy in oligodendrogliomas using metabolomics.

In spite of having been the object of considerable attention, the histopathological grading of oligodendrogliomas is still controversial. The determination of reliable biomarkers capable of improving the malignancy grading remains an essential step in working toward better therapeutic management of patients. Therefore the metabolome of 34 human brain biopsies, histopathologically classified as low‐grade (LGO, N = 10) and high‐grade (HGO, N = 24) oligodendrogliomas, was studied using high‐resolution magic angle spinning nuclear magnetic resonance spectroscopy (HRMAS NMR) and multivariate statistical analysis. The classification model obtained afforded a clear distinction between LGOs and HGOs and provided some useful insights into the different metabolic pathways that underlie malignancy grading. The analysis of the most discriminant metabolites in the model revealed the presence of tumoral hypoxia in HGOs. The statistical model was then used to study biopsy samples that were classified as intermediate oligodendrogliomas (N = 6) and glioblastomas (GBMs) (N = 30) by histopathology. The results revealed a gradient of tumoral hypoxia increasing in the following direction: LGOs, intermediate oligodendrogliomas, HGOs, and GBMs. Moreover upon analysis of the clinical evolution of the patients, the metabolic classification seems to provide a closer correlation with the actual patient evolution than the histopathological analysis. Magn Reson Med 59:959–965, 2008.

Caudate nucleus and social cognition: neuropsychological and SPECT evidence from a patient with focal caudate lesion.

Most studies in social cognition have focused on developmental diseases or analyzed the consequences of acquired frontal lesions on the integrity of Theory of Mind (ToM), but, to our knowledge, none to date has addressed the eventual consequences of damage to the basal ganglia on ToM. To investigate the possible consequences of such lesions on social cognition, we tested a selected patient, MVG, a 44-year-old man with a focal caudate nucleus (CN) lesion following stroke. In the aftermath of this stroke, MVG shows loss of empathy and difficulties recognizing emotions in others. The dual aims of this study were first, to evaluate the implications of CN on ToM and recognition of emotion, and second, to discuss these results as a consequence of a disconnection of the sub-cortical orbito-frontal (OF) loop due to caudate damage. We performed a complete neuropsychological assessment of MVG, as well as different tasks evaluating social cognition, such as the Faux-Pas Test and the Reading the Eyes in the Mind Test. No deficits were found in the neuropsychological tests. However, on tasks assessing social cognition, MVG showed impairments in the warm or affective part of ToM as well as in the ability to recognize negative emotions (i.e., sadness and fear). These results indicate that damage to the head of the left CN can lead to impairment of ToM and emotion recognition. Furthermore, the data shows that, in MVG, such impairment appears to be due to a disconnection of the sub-cortical OF circuit resulting from damage to the CN. Neuro-imaging data tends to confirm this hypothesis by bringing out a hypo-perfusion in both, the territory of his left CN and prefrontal (i.e., ventromedial) brain areas.

Neural responses associated with positive and negative emotion processing in patients with left versus right temporal lobe epilepsy

Studies on emotion processing in patients with temporal lobe epilepsy have dealt mainly with the processing of negative emotions. To further understand the neural basis of emotional disorders in temporal lobe epilepsy, we studied patterns of brain activation induced by implicit processing of negative and positive emotions perceived through facial expressions and emotionally salient stimuli in candidates for surgical treatment of intractable epilepsy. Using functional MRI, we compared, in patients with mesial temporal lobe epilepsy and healthy subjects, the patterns of brain activation elicited by the implicit processing of fearful, sad, and happy faces and pleasant and unpleasant scenes. The results revealed different patterns of activation in patients with left and right mesial temporal lobe epilepsy, compared with healthy subjects, suggesting that the left and right mesial temporal regions are involved differently in emotion processing, which could be related to different contributions in emotional arousal.

The assessment of the quality of the graft in an animal model for lung transplantation using the metabolomics 1H high-resolution magic angle spinning NMR spectroscopy

Standards are needed to control the quality of the lungs from nonheart‐beating donors as potential grafts. This was here assessed using the metabolomics 1H high‐resolution magic angle spinning NMR spectroscopy. Selective perfusion of the porcine bilung block was set up 30 min after cardiac arrest with cold Perfadex®. Lung alterations were analyzed at 3, 6, and 8 h of cold ischemia as compared to baseline and to nonperfused lung. Metabolomics analysis of lung biopsies allowed identification of 35 metabolites. Levels of the majority of the metabolites increased over time at 4°C without perfusion, indicating cellular degradation, whereas levels of glutathione decreased. When lung was perfused at 4°C, levels of the majority of the metabolites remained stable, including levels of glutathione. Levels of uracil by contrast showed a reverse profile, as its signal increased over time in the absence of perfusion while being totally absent in perfused samples. Our results showed glutathione and uracil as potential biomarkers for the quality of the lung. The metabolomics 1H high‐resolution magic angle spinning NMR spectroscopy can be efficiently applied for the assessment of the quality of the lung as an original technique characterized by a rapid assessment of intact biopsy samples without extraction and can be implemented in hospital environment. Magn Reson Med, 2012.

Lyme neuroborreliosis and dementia.

INTRODUCTIONnDescriptions of Lyme disease and dementia are rare.nnnOBJECTIVEnTo describe patients with dementia and a positive intrathecal anti-Borrelia antibody index (AI), specific for neuroborreliosis.nnnMETHODSnAmong 1,594 patients seen for dementia, we prospectively identified and studied 20 patients (1.25%) with dementia and a positive AI. Patients underwent a battery of neuropsychological tests brain, MRI, FDG-PET, and cerebrospinal fluid (CSF) analysis. An etiological diagnosis of the dementia was made at the end of the follow-up of 5.0 ± 2.9 years.nnnRESULTSnWe found two groups of patients with dementia, the first (n = 7, 0.44%) with certain neuroborreliosis and stability or mild improvement of dementia after treatment by antibiotics and the second (n = 13, 0.81%) with progressive worsening of dementia, despite the antibiotics. In the second group, the final diagnoses were Alzheimers disease (AD) (n = 4), AD and Lewy body disease (LBD) (n = 3), LBD (n = 1), FTLD (n = 3), hippocampal sclerosis (n = 1), and vascular dementia (n = 1). We did not observe any differences in cognitive test between the two patient groups at baseline. Brain MRI showed more focal atrophy and FDG-PET showed more frontal hypometabolism in the second group. Tau, p-tau, and Aβ42 concentrations in the CSF were normal in the neuroborreliosis group, and coherent with diagnosis in the second.nnnCONCLUSIONnPure Lyme dementia exists and has a good outcome after antibiotics. It is advisable to do Lyme serology in demented patients, and if serology is positive, to do CSF analysis with AI. Neurodegenerative dementia associated with positive AI also exists, which may have been revealed by the involvement of Borrelia in the CNS.

Metabolomic profile of the adrenal gland: from physiology to pathological conditions

In this study, we i) assessed the metabolic profile of the normal adrenal cortex and medulla of adult human subjects by means of (1)H-high-resolution magic-angle spinning nuclear magnetic resonance (HRMAS NMR) spectroscopy; ii) compared the biochemical profile of adenoma (Ad), adrenal cortical carcinoma (ACC), and pheochromocytoma (PCC) samples with that of healthy adrenal tissue samples; and iii) investigated the metabolic differences between ACCs and Ads as well as between ACCs and PCCs. Sixty-six tissue samples (13 adrenal cortical tissue, eight medullary tissue, 13 Ad, 12 ACC, and 20 PCC samples) were analyzed. Adrenaline and noradrenaline were undetectable in cortical samples representing the metabolic signature of the tissue derived from neural crest. Similarity between the metabolic profile of Ads and that of the normal adrenal cortex was shown. Inversely, ACC samples clearly made up a detached group exhibiting the typical stigmata of neoplastic tissue such as choline-containing compounds, biochemical markers of anaerobic processes, and increased glycolysis. Significantly higher levels of lactate, acetate, and total choline-containing compounds played a major role in the differentiation of ACCs from Ads. Moreover, the high fatty acid content of ACCs contributed to the cluster identification of ACCs. Of the 14 sporadic PCC samples, 12 exhibited predominant or exclusive noradrenaline secretion. The noradrenaline:adrenaline ratio was inverted in the normal medullary tissue samples. Multiple endocrine neoplasia type 2- and NF1-related PCC samples exhibited both adrenaline and noradrenaline secretion. In the von Hippel-Lindau disease-related PCC samples, only noradrenaline secretion was detected by HRMAS NMR spectroscopy. This study is one of the first applications of metabolomics to adrenal pathophysiology and it is the largest study to report HRMAS NMR data related to the adrenal cortex and adrenal cortical tumors.

Gray Matter Volume Decreases in Elderly Patients with Schizophrenia: A Voxel-based Morphometry Study

BACKGROUNDnAged patients (>50 years old) with residual schizophrenic symptoms differ from young patients. They represent a subpopulation with a more unfavorable Kraepelinian course and have an increased risk (up to 30%) for dementia of unknown origin. However, our current understanding of age-related brain changes in schizophrenia is derived from studies that included less than 17% of patients who were older than 50 years of age. This study investigated the anatomical distribution of gray matter (GM) brain deficits in aged patients with ongoing schizophrenia.nnnMETHODSnVoxel-based morphometry was applied to 3D-T1 magnetic resonance images obtained from 27 aged patients with schizophrenia (mean age of 60 years) and 40 age-matched normal controls.nnnRESULTSnOlder patients with schizophrenia showed a bilateral reduction of GM volume in the thalamus, the prefrontal cortex, and in a large posterior region centered on the occipito-temporo-parietal junction. Only the latter region showed accelerated GM volume loss with increasing age. None of these results could be accounted for by institutionalization, antipsychotic medication, or cognitive scores.nnnCONCLUSIONSnThis study replicated most common findings in patients with schizophrenia with regard to thalamic and frontal GM deficits. However, it uncovered an unexpected large region of GM atrophy in the posterior tertiary cortices. The latter observation may be specific to this aged and chronically symptomatic subpopulation, as atrophy in this region is rarely reported in younger patients and is accelerated with age.

NMR HRMAS spectroscopy of lung biopsy samples: Comparison study between human, pig, rat, and mouse metabolomics

Using the metabolomics by NMR high‐resolution magic angle spinning spectroscopy, we assessed the lung metabolome of various animal species in order to identify the animal model that could be substituted to human lung in studies on fresh lung biopsies.

Cold ischemia with selective anterograde in situ pulmonary perfusion preserves gas exchange and mitochondrial homeostasis and curbs inflammation in an experimental model of donation after cardiac death

The aim of this study was to assess the functional preservation of the lung graft with anterograde lung perfusion in a model of donation after cardiac death. Thirty minutes after cardiac arrest, in situ anterograde selective pulmonary cold perfusion was started in six swine. The alveolo‐capillary membrane was challenged at 3, 6, and 8 h with measurements of the mean pulmonary arterial pressure (mPAP), the pulmonary vascular resistance (PVR), the PaO2/FiO2 ratio, the transpulmonary oxygen output (tpVO2), and the transpulmonary CO2 clearance (tpCO2). Mitochondrial homeostasis was investigated by measuring maximal oxidative capacity (Vmax) and the coupling of phosphorylation to oxidation (ACR, acceptor control ratio) in lung biopsies. Inflammation and induction of primary immune response were assessed by measurement of tumor necrosis factor alpha (TNFα), interleukine‐6 (IL‐6) and receptor for advanced glycation endproducts (RAGE) in bronchoalveolar lavage fluid. Data were compared using repeated measures Anova. Pulmonary hemodynamics (mPAP: P = 0.69; PVR: P = 0.46), oxygenation (PaO2/FiO2: P = 0.56; tpVO2: P = 0.46), CO2 diffusion (tpCO2: P = 0.24), mitochondrial homeostasis (Vmax: P = 0.42; ACR: P = 0.8), and RAGE concentrations (P = 0.24) did not significantly change up to 8 h after cardiac arrest. TNFα and IL‐6 were undetectable. Unaffected pulmonary hemodynamics, sustained oxygen and carbon dioxide diffusion, preserved mitochondrial homeostasis, and lack of inflammation suggest a long‐lasting functional preservation of the graft with selective anterograde in situ pulmonary perfusion.