Can NIRS be a surrogate indicator of elective shunt in carotid endarterectomy? A single-center observational retrospective study says no.

BACKGROUND: Neuromonitoring during carotid endarterectomy (CEA) under general anesthesia is desirable and may be useful for preventing brain ischemia, but the selection of the most appropriate method remains controversial. PURPOSE: To determine the effectiveness of near infrared spectroscopy (NIRS) compared to multimodality intraoperative neuromonitoring (IONM) in indicating elective shunts and predicting postoperative neurological status. METHODS: This is a retrospective observational study including 86 consecutive patients with CEA under general anesthesia. NIRS and multimodality IONM were performed during the procedure. IONM included electroencephalography (EEG), somatosensory evoked potentials (SSEPs) and transcranial motor-evoked potentials (TcMEPs). Sensitivity, specificity, and positive and negative predictive values (PPV and NPV) were calculated for each neuromonitoring modality. RESULTS: NIRS presented a sensitivity and a specificity for detecting brain ischemia of 77.7% and 89.6%, respectively (PPV = 46.6% and NPV = 97.2%). In contrast, a 100% sensitivity and specificity for multimodality IONM was determined (PPV and NPV = 100%). No significant difference (in demographical or clinical data) between "true positive" and "false-positive" patients was identified. Among the methods included in multimodality IONM, EEG showed the best results for predicting postoperative outcome after CEA (PPV and NPV=100%). CONCLUSION: NIRS is inferior to multimodality IONM in detecting brain ischemia and predicting postoperative neurological status during CEA under general anesthesia.

Androgen Receptor Activity Is Associated with Worse Survival in Glioblastoma.

BACKGROUND: Some evidence about the role of the androgen receptor (AR) in pathogenesis of glioblastoma have been reported, but no study has focused on measuring the activity of the AR in GB. Therefore, the aim of this work is to study the role of AR and its activity as prognostic biomarkers in glioblastoma (GB). METHODS: Molecular and clinical data from The Cancer Genome Atlas database were used. The AR-expression at protein-level was obtained from reversed phase protein array (RPPA) assays. The AR-activity was determined by calculating the AR-score, an index calculated by using the expression (at RNA-level) of 13 androgen-responsive-genes. Univariate and multivariate Cox-regression analyses were performed. Finally, a correlation analysis was conducted between protein expression data and the AR-score. RESULTS: Two-hundred and thirty-three patients were included. RPPA data showed a mean AR abundance of 0.027(Statistical Deviation = 0.38) in GB. The univariate Cox-regression analysis showed that the AR-Score was associated with a worse prognosis (Hazard Ratio (HR) = 1.070) while the AR-expression did not show any relationship with survival (HR = 0.869). The association of the AR-score with worse overall survival (OS) was still significant in the multivariate analysis (HR = 1.054). The highest correlation coefficients between the AR-score and RPPA were identified in a group of proteins involved in apoptotic process regulation. CONCLUSIONS: GB patients with a high AR-activity present a worse prognosis in terms of OS. Thus, the activity of the AR may have a pathogenic role in GB. In this regard, the activation of the AR in GB may be associated with a dysregulation of apoptosis.

Volcano: Between Structural Vulnerabilities and Collective Defence of Honor in Communities Surrounding an Open Dumpsite.

This study analyzes the dynamics in which structural vulnerabilities are shaped and expressed in the day-to-day lives of people making a living from a garbage dump in Argentina. It is a mixed methods case study, qualitative driven with a collaborative cycle (2016-2021). The study is embedded in medical anthropology, social epidemiology and Latin America Social Medicine, with the focus on the ways people respond to inequalities locally. The findings contribute to the field of health disparities in three directions: 1) the description of patterns of segregation in South America peripheries, shedding light on cumulative disadvantages and multiple exposures; 2) the experience of living enmeshed in places with strong stigmas, revising the ways this source of discrimination become social suffering; and 3) the detection of the impact of collective action and social capital in providing material and symbolic resources for restoring dignity and honour that challenge depreciated status.

Anaesthesia and multimodality intraoperative neuromonitoring in carotid endarterectomy. Chronological evolution and effects on intraoperative neurophysiology.

Contingency data was retrospectively collected to evaluate the historical and current ability to provide multimodality intraoperative neurophysiological monitoring during carotid endarterectomy under two conditions: total intravenous anaesthesia (TIVA) and low dose halogenated anaesthesia (SEVO). 229 patients were monitored during carotid endarterectomy procedures under general anaesthesia between 2012 and 2020. 121 Patients were monitored with SEVO at a minimum alveolar concentration less than 0.7 and 108 were monitored using TIVA, according to common anaesthetic practice standards in our hospital across the years. Multimodality IONM was established with electroencephalography, somatosensory evoked potentials and motor evoked potentials. As compared to TIVA, patients monitored with SEVO showed significantly higher motor evoked potential thresholds (313.52 ± 77.74 SEVO and 218.93 V ± 103.2 V TIVA p < 0.05) and lower reproducibility. Electroencephalography and somatosensory evoked potentials showed no significant differences among the groups. When using SEVO, multimodality intraoperative neurophysiological monitoring during carotid endarterectomy could mask or miss a motor isolated change in patients in spite of low dose minimum alveolar concentration and of apparently adequate electroencephalography and somatosensory evoked potentials for monitoring. Given these difficulties, we believe the chronological transfer to TIVA could have improved our ability to establish multimodality intraoperative neurophysiological monitoring during carotid endarterectomy in recent times.

Neurofunctional correlates of eye to hand motor transfer.

This work investigates the transfer of motor learning from the eye to the hand and its neural correlates by using functional magnetic resonance imaging (fMRI) and a sensorimotor task consisting of the continuous tracking of a virtual target. In pretraining evaluation, all the participants (experimental and control group) performed the tracking task inside an MRI scanner using their right hand and a joystick. After which, the experimental group practiced an eye-controlled version of the task for 5 days using an eye tracking system outside the MRI environment. Post-training evaluation was done 1 week after the first scanning session, where all the participants were scanned again while repeating the manual pretraining task. Behavioral results show that the training in the eye-controlled task produced a better performance not only in the eye-controlled modality (motor learning) but also in the hand-controlled modality (motor transfer). Neural results indicate that eye to hand motor transfer is supported by the motor cortex, the basal ganglia and the cerebellum, which is consistent with previous research focused on other effectors. These results may be of interest in neurorehabilitation to activate the motor systems and help in the recovery of motor functions in stroke or movement disorder patients.

The Mirror Neuron System in Relapsing Remitting Multiple Sclerosis Patients with Low Disability.

To study the visuospatial/visuoperceptive function using a mirror neuron system (MNS) based approach in multiple sclerosis (MS) patients and a healthy control group. Two task-based fMRIs (an execution task and an observation task) and one resting-fMRI were performed in a group of MS patients (n = 24) and a group of healthy controls (n = 15). The execution and observation tasks consisted of the performance or observation of the index-thumb opposition task. Statistical parametric mapping approaches were used to identify differences in the brain activity and functional connectivity (FC) of the MNS between MS patients and healthy controls. Furthermore, visuospatial and visuoperceptive evaluation was performed by a neuropsychologist on all the participants. No global differences between groups were identified when the activity during both the execution and the observation conditions was tested. Nevertheless, differences in FC maps were identified: healthy controls showed higher connectivity between the MNS regions (between the inferior parietal lobule and the inferior frontal gyrus bilaterally) than MS patients. The absence of differences between the studied groups may be the consequence of the selection of a cohort of MS patients with low disability and with no recent relapse. However, the presence of a decrease in functional connectivity within the MNS in MS patients could indicate the presence of subclinical disability in MNS functioning, not measurable by neuropsychological tests.

Modulation in the mirror neuron system when action prediction is not satisfied.

The ability to understand competitive games is closely connected to the mirror neuron system (MNS). This network is activated not only when an action is performed, but also when it is observed. Apart from allowing the understanding of actions performed by others, the MNS has been implicated in predicting subsequent actions. However, the results concerning the modulation of this network by the final outcome of these predictions are contradictory. These contradictions may be related to the use of complex experimental conditions. The aim of this research is to identify changes in the activity of the MNS when the predictions are or are not satisfied in a simple intransitive action-based game. An event-related functional magnetic resonance imaging study was conducted. It consisted of the observation of videos with two actors playing the well-known rock-paper-scissors game. The participants were asked to predict the response of the second actor when the first actor performed one of the three possible actions. In some videos (congruents) the prediction was satisfied, but in the rest of the videos (incongruents) the prediction was not satisfied. When the result was shown, higher activity in the MNS was observed in the congruent videos than in the incongruent ones. Therefore, the observation of a simple manual game leads to a significant activation of the MNS, and this activity seems to be modulated by the final outcome of a prediction, and when predictions are satisfied the activity is higher.

Radiological and Not Clinical Variables Guide the Surgical Plan in Patients with Glioblastoma.

Background and Purpose: The extent of resection is the most important prognostic factor in patients with glioblastoma. However, the factors influencing the decision to perform a biopsy instead of maximal resection have not been clearly established. The aim of this study was to analyze the factors associated with the intention to achieve maximal resection in glioblastoma patients. Methods: A retrospective single-center case-series analysis of patients with a new diagnosis of glioblastoma was performed. Patients were distributed into two groups: the biopsy (B) and complete resection (CR) groups. To identify factors associated with the decision to perform a B or CR, uni- and multivariate binary logistic regression analyses were performed. Cox regression analysis was also performed in the B and CR groups. Results: Ninety-nine patients with a new diagnosis of glioblastoma were included. Sixty-eight patients (68.7%) were treated with CR. Ring-enhancement and edema volume on presurgical magnetic resonance imaging were both associated with CR. Corpus callosum involvement and proximity to the internal capsule were identified as factors associated with the decision to perform a biopsy. In the multivariate analysis, edema volume (OR = 1.031; p = 0.002) and proximity to the internal capsule (OR = 0.104; p = 0.001) maintained significance and were considered independent factors. In the survival analysis, only corpus callosum involvement (HR = 2.055; p = 0.035) and MGMT status (HR = 0.484; p = 0.027) presented statistical significance in the CR group. Conclusions: The volume of edema and proximity to the internal capsule were identified as independent factors associated with the surgical decision. The radiological evaluation and not the clinical situation of the patient influences the decision to perform a biopsy or CR.

Zonulin as Gatekeeper in Gut-Brain Axis: Dysregulation in Glioblastoma.

Novel biomarkers and therapeutic strategies for glioblastoma, the most common malignant brain tumor with an extremely unfavorable prognosis, are urgently needed. Recent studies revealed a significant upregulation of the protein zonulin in glioblastoma, which correlates with patient survival. Originally identified as pre-haptoglobin-2, zonulin modulates both the intestinal barrier and the blood-brain barrier by disassembling tight junctions. An association of zonulin with various neuroinflammatory diseases has been observed. It can be suggested that zonulin links a putative impairment of the gut-brain barrier with glioblastoma carcinogenesis, leading to an interaction of the gut microbiome, the immune system, and glioblastoma. We therefore propose three interconnected hypotheses: (I) elevated levels of zonulin in glioblastoma contribute to its aggressiveness; (II) upregulated (serum-) zonulin increases the permeability of the microbiota-gut-brain barrier; and (III) this creates a carcinogenic and immunosuppressive microenvironment preventing the host from an effective antitumor response. The role of zonulin in glioblastoma highlights a promising field of research that could yield diagnostic and therapeutic options for glioblastoma patients and other diseases with a disturbed microbiota-gut-brain barrier.

Optimizing the Endoscopic Transorbital Approach: MacCarty Keyhole for Enhanced Surgical Exposure in the Opticocarotid Region.

BACKGROUND: In recent years, the endoscopic transorbital (TO) approach has gained increasing interest for the treatment of middle cranial fossa lesions. We propose a technical refinement to the conventional superior eyelid TO approach, which improves the surgical exposure and augments the working angles when targeting the opticocarotid region. METHODS: Four embalmed adult cadaveric specimens (8 sides) were dissected at the Laboratory of Surgical Neuroanatomy of our institution. A TO approach was performed, with removal of the anterior clinoid process and the lateral orbital rim. Subsequently, the MacCarty keyhole was drilled in the superolateral orbital wall. Given that the lesser sphenoid wing was already drilled in the conventional TO craniectomy, the opening of the keyhole was essentially a lateral extension of the craniectomy. RESULTS: The procedure was successfully conducted in all 4 orbits. Clinoidectomy was performed either before or after extending the craniectomy to the MacCarty point. Extending the craniectomy made anterior clinoidectomy easier, by increasing the surgical exposure, and allowing a more lateral entrance for the endoscope. The extension also facilitated frontal lobe retraction, and it facilitated the optic nerve and carotid artery manipulation. Postoperative computed tomography scans showed a minimal 10-mm craniectomy extension, which remained covered by the temporal muscle after reconstruction. CONCLUSIONS: The modified endoscopic TO approach with the extension of the craniectomy to MacCarty point improves surgical access and visualization of the opticocarotid region. This facilitates anterior clinoidectomy and optic nerve decompression. Although it implies judicious instrument manipulation and a larger incision size, further studies can define its potential benefits.

The Endoscopic Transorbital Approach for Vascular Surgery: An Anterior Circulation Anatomic Study, 2-Dimensional Operative Video.

BACKGROUND AND OBJECTIVES: Minimally invasive endoscopic approaches in cranial base surgery have been developing in the past decades. The transorbital (TO) route is one promising alternative, yet its adequacy for intracranial vascular lesions remains unclear. The present anatomic work aimed to test the feasibility and to provide a qualitative description of the endoscopic TO approach for the anterior circulation, namely the internal carotid artery and the middle cerebral artery. METHODS: Seven embalmed adult cadaveric specimens (12 sides) were used in the study. Each side was approached in 3 successive steps: (1) Superior-eyelid TO approach, with great and lesser sphenoid wing removal. (2) Removal of anterior clinoid process (ACP). (3) Removal of the lateral orbital rim. All the procedures were performed under endoscopic view. RESULTS: The TO approach without removing the ACP allowed to dissect the sphenoidal and lateral segments of the Sylvian fissure with an adequate identification of the middle cerebral artery bifurcation in all specimens. The removal of the ACP allowed further dissection toward the opticocarotid cistern, with the identification of the ophthalmic, posterior communicating, and the anterior choroidal arteries. The internal carotid artery bifurcation and A1 segment were also readily identified. Finally, removal of the lateral orbital rim provided a wider and more comfortable access to the above-mentioned vascular structures. CONCLUSION: According to our anatomic data, the TO approach can be used to reach the main vascular components of the anterior circulation. This opens the field for exploring its application in the treatment of vascular pathology, particularly aneurysms.

Androgen deficiency is associated with a better prognosis in glioblastoma.

BACKGROUND: The androgen receptor (AR) has been demonstrated to play a role in the pathogenesis of glioblastoma; however, the implications of circulating testosterone levels in the biology of glioblastoma remain unknown. AIM: This study aimed to analyze the association between circulating testosterone levels and the prognosis of patients with glioblastoma. METHODS: Forty patients with primary glioblastoma were included in the study. The main prognostic endpoint was progression-free survival (PFS). Circulating testosterone levels were used to determine the state of androgen deficiency (AD). AR expression was analyzed by reverse-transcriptase polymerase chain reaction, Western blot, and immunofluorescence. Survival analysis was performed using the log-rank test and univariate and multivariate Cox regression analysis. RESULTS: Most of the patients showed AR expression, and it was mainly located in the cytoplasm, as well as in the nucleus of tumor cells. Patients with AD presented a better PFS than those patients with normal levels (252.0 vs. 135.0 days; p = 0.041). Furthermore, normal androgenic status was an independent risk factor for progression in a multivariate regression model (hazard ratio = 6.346; p = 0.004). CONCLUSION: Circulating testosterone levels are associated with the prognosis of glioblastoma because patients with AD show a better prognosis than those with normal androgenic status.

Evaluation of Zonulin Expression and Its Potential Clinical Significance in Glioblastoma.

Glioblastoma, the deadliest adult brain tumor, poses a significant therapeutic challenge with a dismal prognosis despite current treatments. Zonulin, a protein influencing tight junctions and barrier functions, has gained attention for its diverse roles in various diseases. This study aimed to preliminarily analyze the circulating and tumor zonulin levels, evaluating their impact on disease prognosis and clinical-radiological factors. Additionally, we investigated in vitro zonulin expression in different glioblastoma cell lines under two different conditions. The study comprised 34 newly diagnosed glioblastoma patients, with blood samples collected before treatment for zonulin and haptoglobin analysis. Tumor tissue samples from 21 patients were obtained for zonulin expression. Clinical, molecular, and radiological data were collected, and zonulin protein levels were assessed using ELISA and Western blot techniques. Furthermore, zonulin expression was analyzed in vitro in three glioblastoma cell lines cultured under standard and glioma-stem-cell (GSC)-specific conditions. High zonulin expression in glioblastoma tumors correlated with larger preoperative contrast enhancement and edema volumes. Patients with high zonulin levels showed a poorer prognosis (progression-free survival [PFS]). Similarly, elevated serum levels of zonulin were associated with a trend of shorter PFS. Higher haptoglobin levels correlated with MGMT methylation and longer PFS. In vitro, glioblastoma cell lines expressed zonulin under standard cell culture conditions, with increased expression in tumorsphere-specific conditions. Elevated zonulin levels in both the tumor and serum of glioblastoma patients were linked to a poorer prognosis and radiological signs of increased disruption of the blood-brain barrier. In vitro, zonulin expression exhibited a significant increase in tumorspheres.

Empathy Modulates the Activity of the Sensorimotor Mirror Neuron System during Pain Observation.

AIM: The aim of this study is to analyze the brain activity patterns during the observation of painful expressions and to establish the relationship between this activity and the scores obtained on the Interpersonal Reactivity Index (IRI). METHODS: The study included twenty healthy, right-handed subjects (10 women). We conducted a task-based and resting-state functional magnetic resonance imaging (fMRI) study. The task involved observing pictures displaying painful expressions. We performed a region of interest (ROI) analysis focusing on the core regions of the sensorimotor mirror neuron system (MNS). Resting-state fMRI was utilized to assess the functional connectivity of the sensorimotor MNS regions with the rest of the cortex using a seed-to-voxel approach. Additionally, we conducted a regression analysis to examine the relationship between brain activity and scores from the IRI subtests. RESULTS: Observing painful expressions led to increased activity in specific regions of the frontal, temporal, and parietal lobes. The largest cluster of activation was observed in the left inferior parietal lobule (IPL). However, the ROI analysis did not reveal any significant activity in the remaining core regions of the sensorimotor MNS. The regression analysis demonstrated a positive correlation between brain activity during the observation of pain and the "empathic concern" subtest scores of the IRI in both the cingulate gyri and bilateral IPL. Finally, we identified a positive relationship between the "empathic concern" subtest of the IRI and the functional connectivity (FC) of bilateral IPLs with the bilateral prefrontal cortex and the right IFG. CONCLUSION: Observing expressions of pain triggers activation in the sensorimotor MNS, and this activation is influenced by the individual's level of empathy.

Biomarkers for characterization and therapeutic orientation in castration-resistant prostate cancer. / Biomarcadores para la caracterización y orientación terapéutica en Cáncer de Próstata Resistente a la Castración (CPRC).

Whole exome sequencing studies haverevealed the molecular landscape of metastatic CastrateResistant Prostate Cancer (mCRPC) providingnew information about prognostic and predictive factorsof response to therapies. These studies highlightedpotentially actionable targets leading to the beginingof the biomarker-driven era in prostate cancer.Alterations in androgen receptor (AR), DNA repair genes,PI3K-AKT-MTOR pathway or in genes involved incell cycle are frequently observed in mCRPC patientsand may be relevant in the resistance induced mechanismto approve therapy in this setting. Poly(ADP-ribose)polymerase (PARP) inhibitor in BRCA mutatedpatients, pembrolizumab (inmune checkpoint inhibitors)in mCRPC patients with mismatch repair genedefects and microsatellite instability and ipatasertib(AKT inhibitor) in patients with loss of function inPTEN are examples on how molecular information canbe useful to improve treatment selection. Nonethelessthe heterogeneity of advanced PC, the lack of consensusregarding the optimal biological source of analysisand the optimal time and technique for the analisysare still challenges that need to be defined in the nextfuture. The aim is to review the current literature concerningprognostic and predictive marker of responseto therapies in the mCRPC setting.

Estudios de secuenciación completa delexoma han revelado el perfil molecular del pacientecon Cáncer de Próstata Resistente a la Castración metastásico(CPRCm) proporcionando nueva informaciónsobre factores pronósticos y predictivos de respuestaa las distintas alternativas terapéuticas. Muchos deestos estudios han resaltado numerosas dianas molecularesaccionables desde un punto de vista farmacológico,conduciéndonos al comienzo de la medicina deprecisión en el Cáncer de Próstata (CP). Alteracionesen el Receptor de Andrógenos (RA), en genes reparadoresde DNA, en la vía de PI3K-AKT-MTOR o en genesimplicados en el ciclo celular son frecuentementeobservadas en CPRCm y pueden ser relevantes en la selección terapéutica y en la comprensión de los mecanismosde resistencia.Los inhibidores de la poli (ADP-ribosa) polimerasaen pacientes con mutaciones en BRCA, pembrolizumab(inhibidor de los puntos de control inmunológico)en pacientes CPRCm con alteraciones en genesimplicados en el "mismatch repair" o inestabilidad demicrosatélites e ipatasertib (inhibidor de AKT) en pacientescon pérdida de función de PTEN son ejemplosde cómo la información molecular puede ser útil paraoptimizar la selección terapéutica en este escenario.No obstante, la heterogeneidad del CP avanzado, lafalta de consenso sobre la fuente biológica óptima parael análisis, el momento y la técnica de análisis continúansiendo desafíos a definir en un fututo próximo.El objetivo es revisar la literatura actual sobre marcadorespronósticos y predictivos de respuesta a tratamientoen el entorno del CPRCm.

High Expression of FOXP2 Is Associated with Worse Prognosis in Glioblastoma.

OBJECTIVE: FOXP2 expression has been associated with the prognosis of some tumors, but the role of FOXP2 in glioblastoma remains unclear. The aim of the present work is to study the role of FOXP2 as a prognostic biomarker in glioblastoma. METHODS: This is a retrospective observational case series study in which the expression of FOXP2 has been analyzed both at protein level (immunohistochemistry, n = 62) and at mRNA level (RNAseq, in a cohort of glioblastoma patients from The Cancer Genome Atlas [TCGA] database, n = 148). Other molecular and clinical data have also been included in the study, with special focus on miRNA expression data. Survival analysis using log-rank test and COX-regression have been used. Non-parametric statistical tests were also used to study differences between low and high FOXP2 expression groups. RESULTS: Patients with a high expression of FOXP2 protein showed a worse prognosis than those patients with low expression in progression-free survival (hazard ratio 1.711; P = 0.034) and overall survival (hazard ratio 1.809; P = 0.014). These associations were still statistically significant in multivariate analysis. No prognostic association was found with FOXP2 RNA expression. Interestingly, 2 miRNAs that target FOXP2 (hsa-miR-181a-2-3p and hsa-miR-20a-3p) showed an interaction effect on overall survival with FOXP2 expression. A low level of these miRNA expression was associated with a significantly worse prognosis in patients with high FOXP2 RNA expression (log-rank test; P < 0.05). CONCLUSIONS: Greater expression of FOXP2 at the protein level is associated with a worse prognosis. This protein expression may be regulated by the expression of specific miRNAs that target FOXP2 mRNA: hsa-miR-181a-2-3p and hsa-miR-20a-3p.

Music Style Not Only Modulates the Auditory Cortex, but Also Motor Related Areas.

The neuroscience of music has recently attracted significant attention, but the effect of music style on the activation of auditory-motor regions has not been explored. The aim of the present study is to analyze the differences in brain activity during passive listening to non-vocal excerpts of four different music genres (classical, reggaeton, electronic and folk). A functional magnetic resonance imaging (fMRI) experiment was performed. Twenty-eight participants with no musical training were included in the study. They had to passively listen to music excerpts of the above genres during fMRI acquisition. Imaging analysis was performed at the whole-brain-level and in auditory-motor regions of interest (ROIs). Furthermore, the musical competence of each participant was measured and its relationship with brain activity in the studied ROIs was analyzed. The whole brain analysis showed higher brain activity during reggaeton listening than the other music genres in auditory-related areas. The ROI-analysis showed that reggaeton led to higher activity not only in auditory related areas, but also in some motor related areas, mainly when it was compared with classical music. A positive relationship between the melodic-Music Ear Test (MET) score and brain activity during reggaeton listening was identified in some auditory and motor related areas. The findings revealed that listening to different music styles in musically inexperienced subjects elicits different brain activity in auditory and motor related areas. Reggaeton was, among the studied music genres, the one that evoked the highest activity in the auditory-motor network. These findings are discussed in connection with acoustic analyses of the musical stimuli.

Changes in resting-state measures of prostate cancer patients exposed to androgen deprivation therapy.

The aim of the present work is to describe the differences in rs-fMRI measures (Amplitude of low frequency fluctuations [ALFF], Regional Homogeneity [ReHo] and Functional Connectivity [FC]) between patients exposed to Androgen deprivation therapy (ADT) and a control group. Forty-nine ADT patients and fifteen PC-non-ADT patients (Controls) were included in the study. A neuropsychological evaluation and a resting-state fMRI was performed to evaluate differences in ALFF and ReHo. Region of interest (ROI) analysis was also performed. ROIs were selected among those whose androgen receptor expression (at RNA-level) was the highest. FC analysis was performed using the same ROIs. Higher ALFF in frontal regions and temporal regions was identified in Controls than in ADT patients. In the ROI analysis, higher activity for Controls than ADT patients was shown in the left inferior frontal gyrus and in the left precentral gyrus. Lower ALFF in the right hippocampus and the lateral geniculate nucleus of the right thalamus was identified for Controls than ADT patients. Higher ReHo was observed in Controls in the left parietal-occipital area. Finally, ADT patients presented an increase of FC in more regions than Controls. These differences may reflect an impairment in brain functioning in ADT users.

Direct cortical stimulation with cylindrical depth electrodes in the interhemispheric fissure for leg motor evoked potential monitoring.

OBJECTIVE: To evaluate cylindrical depth electrodes in the interhemispheric fissure as an alternative to subdural strip electrodes for direct cortical stimulation (DCS) leg motor evoked potential (MEP) monitoring. METHODS: A cylindrical depth electrode was positioned in the interhemispheric fissure of 37 patients who underwent supratentorial brain surgery. Leg sensory and motor cortices were localized by highest tibial nerve somatosensory evoked potential amplitude and lowest DCS leg MEP threshold; the lowest-threshold electrode was then used for DCS leg MEP monitoring. RESULTS: Intraoperative leg MEPs were obtained from all the patients in the series. The mean intensity applied for leg MEP monitoring with the cylindrical depth electrode was 15.2 ± 4.0 mA. No complications secondary to neurophysiological monitoring were detected. CONCLUSIONS: Lower extremity MEPs were consistently recorded using a multi-contact cylindrical depth electrode in the interhemispheric fissure by DCS. SIGNIFICANCE: Cylindrical depth electrodes may be a safe and effective alternative for DCS in the interhemispheric fissure, where subdural strips are difficult to place.

Visual inputs decrease brain activity in frontal areas during silent lipreading.

AIM: The aim of the present work is to analyze the modulation of the brain activity within the areas involved in lipreading when an additional visual stimulus is included. METHODS: The experiment consisted of two fMRI runs (lipreading_only and lipreading+picture) where two conditions were considered in each one (oral speech sentences condition [OSS] and oral speech syllables condition [OSSY]). RESULTS: During lipreading-only, higher activity in the left middle temporal gyrus (MTG) was identified for OSS than OSSY; during lipreading+picture, apart from the left MTG, higher activity was also present in the supplementary motor area (SMA), the left precentral gyrus (PreCG) and the left inferior frontal gyrus (IFG). The comparison between these two runs revealed higher activity for lipreading-only in the SMA and the left IFG. CONCLUSION: The presence of a visual reference during a lipreading task leads to a decrease in activity in frontal areas.