Positive Mapping Research Articles

DMMGNet: A discrimination mapping and memory bank mean guidance-based network for high-performance few-shot industrial anomaly detection

For deep learning-based industrial anomaly detection, it is still challenging to get adequate images for model training and achieve cold start for cross-product migration, restricting their practical application in real industrial production. Herein, an innovative few-shot anomaly detection network DMMGNet based on discrimination mapping and memory bank mean guidance strategies are demonstrated, which is trained by a new two-branch data augmentation technique. By separating the features stored in memory bank from the features used for training, the two-branch data augmentation method can significantly improve the robustness of few-shot model training and reduce the redundance of memory bank. In the elaborately designed discrimination mapping module, new negative samples are generated by adding dynamic Gaussian noise to normal samples along the channel dimension in feature space to solve the problem of sample imbalance. Meanwhile, the discrimination mapping module also helps to map the feature distribution of positive samples to the target domain more efficiently and reduce the deviation of feature domain, conducive to a more precise separation of positive and negative samples. In addition, a novel mean guidance approach with an optimized loss function is developed to guide the positive sample feature mapping by specifying the local feature space center to form a clear feature domain contour and enhance the detection accuracy. The multiple experimental results validate that our DMMGNet outperforms the most advanced anomaly detection counterparts on image-level AUROC, showing an increase by 0.3–3 % on both MVTec AD and MPDD benchmarks under several few-shot scenarios.

A phase 2 study of de-escalation in resectable, locally advanced cutaneous squamous cell carcinoma (cSCC) with the use of neoadjuvant pembrolizumab: De-Squamate.

9514 Background: Neoadjuvant anti-Programmed Death therapy has shown a 64% complete or major pathological response rate in patients (pts) with resected stage II-IV(M0) cSCC. The De-Squamate study (NCT05025813) evaluated the feasibility of a risk adapted surgical de-escalation approach guided by clinical, radiological and pathological response in resectable cSCC pts of all sites receiving neoadjuvant pembrolizumab. Methods: This multi-centre, open-labelled, non-randomised, single-arm phase 2 study evaluated the response of neoadjuvant Pembrolizumab for 4 cycles administered IV 200mg Q3W in immunocompetent pts with Stage II-IV (M0) resectable cSCC. Pts underwent CT/MRI and 18F-FDG-PET imaging at baseline and following completion of neoadjuvant pembrolizumab. In those with a complete metabolic response, mapping biopsies of target site(s) were performed and if negative for residual SCC (clinical complete response [CCR]), surgery and post operative radiation therapy (PORT) were omitted. Patients with clinical or radiological residual disease/ positive mapping biopsy underwent surgical resection. PORT was de-escalated if there was a pathological complete response (PCR - no residual tumour cells) or major pathological response (MPR - less than or equal to 10% viable tumour cells). Pts proceeded to 13 cycles of maintenance Pembrolizumab. The primary endpoint was the combined rate of PCR, MPR and CCR following neoadjuvant Pembrolizumab and secondary endpoint includes treatment de-escalation and safety. Results: All 27 patients were enrolled and received a minimum of 2 cycles of neoadjuvant Pembrolizumab. The primary endpoint was observed in 17 patients (63%, 95% CI: 42-80), comprised of PCR (15%), MPR (0%) and CCR (48%). De-escalation of both surgery and PORT was achieved in 48% and a further 15% avoided PORT alone. With a minimum follow up of 6 months, no pts with PCR/MPR/CCR recurred. Investigator assessed treatment-related adverse events ≥ grade 3 was seen in 2 patients (7%). Conclusions: Pembrolizumab led to a high rate of PCR and CCR in resectable cSCC. The de-squamate study design effectively selected pts for surgical and PORT de-escalation and demonstrated a sustained response in this cohort. Clinical trial information: NCT05025813 .

BRUGADA SYNDROME: NEWEST DATA ON RISK STRATIFICATION

Abstract Background Brugada Syndrome (BrS) is a rare genetically based channelopathy responsible for malignant arrhythmias and sudden cardiac death (SCD) in young adults. Objectives The aims was to evaluate prognostic indicators useful for accurate arrhythmic risk stratification in BrS by studying genetic, clinical, anamnestic, instrumental parameters, and those derived from electrophysiological study (EPS) and intracavitary mapping. Materials and Methods 209 patients with Brugada type 1 were recruited between 01/01/2018 and 01/10/2023. Results In the first study, predictive factors related to high arrhythmic risk from the data obtained for the total population of 209 Brugada patients enrolled in our case series include a positive history of cardiogenic syncope (p value 0.000041), having had a resuscitated cardiac arrest (p value 0.00025), presenting positive EPS for inducibility of ventricular tachycardia (p value 0.00032), having a family history of sudden cardiac death (p value < 0.00001), and presenting positive cardiac mapping and MRI for pathological alterations (both with p value > 0.00001). From the data obtained for the subset of 80 Brugada patients with ICD in our case series, predictive factors related to high arrhythmic risk are different from the previously analyzed population: presenting spontaneous type 1 ECG (p value 0.0015), having had a resuscitated cardiac arrest (p value 0.014028), having a family history of sudden cardiac death (p value < 0.00001), and presenting positive mapping, genetics, and cardiac MRI for pathological alterations. Positive EPS and syncope in this subset do not appear to be risk factors, unlike the population of all 209 enrolled patients. Conclusions Multiparametric scores, including the mentioned markers, have been introduced in clinical practice for a better approach in selection. However, new markers are needed to improve risk stratification in BrS patients, especially those in the so–called "gray zone" with intermediate risk. In the future, it will be evaluated through experimental models and genotype–phenotype integration whether such electrical heterogeneity is also associated with specific genetic or structural abnormalities and may represent a new therapeutic target for etiological treatment in BrS patients. In conclusion, there is an urgent need to develop new methods for risk stratification in Brugada syndrome that are sufficiently sensitive, specific, reproducible, and easy to apply.

Conditional indicators

. In this paper, we introduce a large class of (so-called) conditional indicators, on a complete probability space with respect to a sub σ-algebra. A conditional indicator is a positive mapping, which is not necessary linear, but may share common features with the conditional expectation, such as the tower property or the projection property. Several characterizations are formulated. Beyond the definitions, we provide some non trivial examples that are used in finance and may inspire new developments in the theory of operators on Riesz spaces.

Experience in awake glioma surgery in a South American center. Correlation between intraoperative evaluation, extent of resection and functional outcomes

IntroductionGliomas are the second most frequent primary brain tumors. Surgical resection remains a crucial part of treatment, as well as maximum preservation of neurological function. For this reason awake surgery has an important role.The objectives of this article are to present our experience with awake surgery for gliomas in a South American center and to analyze how intraoperative functional findings may influence the extent of resection and neurological outcomes. Materials and methodsRetrospective single center study of a cohort of adult patients undergoing awake surgery for brain glioma, by the same neurosurgeon, between 2012 and 2022 in the city of Buenos Aires, Argentina. ResultsA total of 71 patients were included (mean age 34 years, 62% males). Seventy seven percent of tumors were low grade, with average extent of resection reaching 94% of preoperative volumetric assessment. At six months follow up, 81.7% of patients presented no motor or language deficit.Further analysis showed that having a positive mapping did not have a negative impact in the extent of resection, but was associated with short term postoperative motor and language deficits, among other variables, with later improvement. ConclusionAwake surgery for gliomas is a safe procedure, with the proper training. In this study it was observed that guiding the resection by negative mapping did not worsen the results and that positive subcortical mapping correlated with short term postoperative neurological deficits with posterior improvement within six months in most cases.

Awake brain mapping by direct cortical stimulation; technical note to get higher resection rate and low morbidity in low-grade glioma patients.

Direct cortical stimulation has been used for brain mapping and localization of eloquent areas in awake patients. This simplified technique is to provide the positive areas, which can be preserved if the tumor or lesions are involved eloquent areas. The main objective of this study is to determine whether direct cortical stimulation in awake brain mapping for low-grade glioma patients increases the rate of resection or not. The authors present a retrospective study between 2020 to 2022 that includes 35 cases in a single center, to get higher resection rate, and their consequences in awake craniotomy in low-grade glioma patients. Here, two neurosurgeons were involved and the minimum follow-up was 12 months. The authors achieved 80% removal of tumors. To get higher resection rate we emphasized negative mapping with prior anatomical analysis to understand functional realignment. Stimulation-related complications will be thoroughly discussed with a potential future direction to minimize the issues. The authors used PROMIS score to measure patients physical and mental health status and kernofsky score to measure performance status before and after successful surgery. The authors found three cases of transient deficit in repetitive stimulation. Repeated stimulation to identify the eloquent areas with low voltage frequency is a good option. Numbness in the face related to stimulation may continue for 6 weeks. Functional realignment in shifted brain and edema can be seen while doing cortical and subcortical stimulation. Most of the stimulation from low to high for language mapping may vary from patient to patient. For safe removal of low-grade glioma a steep learning curve is needed to find out the negative areas, though the authors emphasize positive mapping of areas to secure the maximum eloquence.

Awake brain mapping paradigms for nondominant hemisphere gliomas.

Traditionally, resection of nondominant hemisphere brain tumors was performed under general anesthesia. An improved understanding of right-lateralized neural networks has led to a paradigm shift in recent decades, where the right or nondominant hemisphere is no longer perceived as "functionally silent." There is an increasing interest in awake brain mapping for nondominant hemisphere resections. The objective of this study was to perform a comprehensive review of the existing brain mapping paradigms for patients with nondominant hemisphere gliomas undergoing awake craniotomies. In accordance with PRISMA guidelines, systematic searches of the Medline, Embase, and American Psychological Association PsycInfo databases were undertaken from database inception to July 1, 2023. Studies providing a description of the intraoperative mapping paradigm used to assess cognition during an awake craniotomy for resection of a nondominant hemisphere glioma were included. The search yielded 1084 potentially eligible articles. Thirty-nine unique studies reporting on 788 patients were included in the systematic review. The most frequently tested cognitive domains in patients with nondominant hemisphere tumors were spatial attention/neglect (17/39 studies, 43.6%), speech-motor/language (17/39 studies, 43.6%), and social cognition (9/39 studies, 23.1%). Within the frontal lobe, the highest number of positive mapping sites was identified for speech-motor/language, spatial attention/neglect, dual tasking assessing motor and language function, working memory, and social cognition. Within the parietal lobe, eloquence was most frequently found upon testing spatial attention/neglect, speech-motor/language, and calculation. Within the temporal lobe, the assessment of spatial attention/neglect yielded the highest number of positive mapping sites. Cognitive testing in the nondominant hemisphere is predominantly focused on evaluating two domains: spatial attention/neglect and the motor aspects of speech/language. Multidisciplinary teams involved in awake brain mapping should consider testing an extended range of functions to minimize the risk of postoperative deficits and provide valuable information about anatomo-functional organization of cognitive networks.

Representation of negative numbers: point estimation tasks using multi-reference sonification mappings.

In this study, we examine different approaches to the presentation of Y coordinates in mobile auditory graphs, including the representation of negative numbers. These studies involved both normally sighted and visually impaired users, as there are applications where normally sighted users might employ auditory graphs, such as the unseen monitoring of stocks, or fuel consumption in a car. Multi-reference sonification schemes are investigated as a means of improving the performance of mobile non-visual point estimation tasks. The results demonstrated that both populations are able to carry out point estimation tasks with a good level of performance when presented with auditory graphs using multiple reference tones. Additionally, visually impaired participants performed better on graphs represented in this format than normally sighted participants. This work also implements the component representation approach for negative numbers to represent the mapping by using the same positive mapping reference for the digit and adding a sign before the digit which leads to a better accuracy of the polarity sign. This work contributes to the areas of the design process of mobile auditory devices in human-computer interaction and proposed a methodological framework related to improving auditory graph performance in graph reproduction.

Application of a Standardized Treatment Paradigm as a Strategy to Achieve Optimal Onco-Functional Balance in Glioma Surgery.

Gliomas, characterized by their invasive persistence and tendency to affect critical brain regions, pose a challenge in surgical resection due to the risk of neurological deficits. This study focuses on a personalized approach to achieving an optimal onco-functional balance in glioma resections, emphasizing maximal tumor removal while preserving the quality of life. A retrospective analysis of 57 awake surgical resections of gliomas at the National University Hospital, Singapore, was conducted. The inclusion criteria were based on diagnosis, functional boundaries determined by direct electrical stimulation, preoperative Karnofsky Performance Status score, and absence of multifocal disease on MRI. The treatment approach included comprehensive neuropsychological evaluation, determination of suitability for awake surgery, and standard asleep-awake-asleep anesthesia protocol. Tumor resection techniques and postoperative care were systematically followed. The study included 53 patients (55.5% male, average age 39 years), predominantly right-handed. Over half reported seizures as their chief complaint. Tumors were mostly low-grade gliomas. Positive mapping of the primary motor cortex was conducted in all cases, with awake surgery completed in 77.2% of cases. New neurological deficits were observed in 26.3% of patients at 1 month after operation; most showed significant improvement at 6 months. The standardized treatment paradigm effectively achieved an optimal onco-functional balance in glioma patients. While some patients experienced neurological deficits postoperatively, the majority recovered to their preoperative baseline within 3 months. The approach prioritizes patient empowerment and customized utilization of functional mapping techniques, considering the challenge of preserving diverse languages in a multilingual patient population.

Perioperative seizure in patients undergoing brain mapping under awake craniotomy for language-related eloquent region gliomas: a prospective study.

Awake craniotomy (AC) is standard of care for lesions of eloquent brain areas. One important complication during AC is occurrence of intraoperative seizure (IOS), reported to occur among 3.4-20% of the patients. In this study, we report our experience with IOS during AC for resection of gliomas of the language eloquent regions and evaluate the predisposing factors and consequences. Patients who underwent AC for language related regions of the dominant hemisphere from August 2018 to June 2021 were enrolled. The rate of IOS during AC and relationship between predisposing factors and IOS were evaluated. Sixty-five patients were enrolled (mean age: 44.4±12.5 years). Among 6 patients with IOS (9.2%), only one needed conversion to general anesthesia (GA) due to repeated seizures; while in the remaining 5, AC accomplished successfully despite one seizure attack in the awake phase. Tumor location (especially premotor cortex lesions, P=0.02, uOR:12.0, CI: 1.20-119.91), higher tumor volume (P=0.008, uOR: 1.9, CI: 1.06-1.12) and a functional tumor margin during surgery (P=0.000, uOR: 3.4, CI: 1.47-12.35) were significantly linked with IOS. Occurrence of IOS was associated with a longer ICU stay after surgery and worse immediate neurological outcome, but had no impact on the late neurological status. IOS can usually be managed during AC without need to converting to GA. Those with larger tumors, frontal premotor lesions and positive brain mapping are susceptible to IOS. Early neurological deterioration observed after IOS, seems to be transient with no major long-term consequence on the neurological outcome.

Carbonate-rock aquifers in arid environments (central Tunisia, Western Mediterranean province): gravity and time domain electromagnetic methods investigations

Gravity and time domain electromagnetic (TDEM) methods were used in this study to investigate the subsurface hydrogeology of the carbonate-rock aquifer in arid environments (central Tunisia, Western Mediterranean province). The El Houdh basin can be considered an appropriate case for evaluating the vulnerability of groundwater resources under present-day climate change. The identification of structural context and the discontinuities affecting the Eocene or Campanian to Maastrichtian carbonates is an important key to recognize water recharge and discharge pathways and to develop effective and long-term groundwater exploration strategies. First, we have produced an available residual gravity field using a specific Gaussian filter. Then, we generated derivative maps, Euler deconvolution solutions map and a 3D gravity model to delineate different anomalies and to estimate the depth-to-basement parameter and the subsurface density contrasts. Positive and negative anomalies mapping and 3D gravity modelling showed that the El Houdh basin is associated with an asymmetric ‘perched syncline’ with a segmentation into NE–SW sub-basins (local negative residual anomalies) separated by NW–SE lineaments. The TDEM survey was calibrated using boreholes to image the karst saturated and unsaturated zone and to deduce the epikarst and endokarst relationship. Finally, the proposed method provides a fast and valuable approach for better management of hydrogeological exploitation. Thematic collection: This article is part of the Climate change and resilience in Engineering Geology and Hydrogeology collection available at: https://www.lyellcollection.org/cc/climate-change-and-resilience-in-engineering-geology-and-hydrogeology

On the Solvability of a Periodic Problem for a System of Ordinary Differential Equations with the Main Positive Homogeneous Nonlinearity

We study the solvability of a periodic problem for a system of ordinary differential equations in which we separate the main nonlinear part that is positive homogeneous mapping (of order greater than unity), with the rest called a perturbation. It is proved that if the unperturbed system of equations has no nonzero bounded solutions, then the periodic problem is solvable under any perturbation if and only if the degree of the positive homogeneous mapping on the unit sphere is nonzero. The result obtained is of interest from the point of view of the application and development of methods of nonlinear analysis in the theory of differential and integral equations.

Recovery of Visual Field After Awake Stimulation Mapping of the Optic Pathway in Glioma Patients.

Brain mapping during awake craniotomy for gliomas can help preserve neurological functions, including maintenance of central and peripheral vision. However, the consecutive changes in the visual field remain unknown. We retrospectively assessed 14 patients who underwent awake craniotomy for gliomas infiltrating into the optic radiation. Cortico-subcortical direct electrical stimulation (DES) was intraoperatively applied until transient visual symptoms were elicited and recorded. The visual fields were examined consecutively in the preoperative period and postoperative subacute and chronic periods. To evaluate the anatomo-functional validity of the recordings, all DES-elicited points were overlaid onto a three-dimensional template that included the optic radiation, using voxel-based morphometry (VBM) mapping. All patients experienced visual symptoms that were classified as phosphenes, blurred vision, or hallucinations during DES, and surgical resection was limited to within the functional boundaries. In VBM, almost all the subcortical positive mapping points overlapped with the surface of the optic radiation, and the distribution of sites that induced visual phenomena in the upper or lower visual fields could be differentiated in the anatomical space. We observed no postoperative visual deficit in four patients (29%), time-dependent improvements in five out of eight patients that presented transient quadrantanopia or partial visual defect (36% out of 57%), and permanent hemianopsia (14%) in two patients with occipital lesions. Intraoperative DES that identifies and preserves optic radiation in awake craniotomy for gliomas is a reliable and effective technique to reduce risk of permanent deficits, but has a low success rate in patients with occipital involvement.

Preoperative Navigated Transcranial Magnetic Stimulation: New Insight for Brain Tumor-Related Language Mapping.

Preoperative brain mapping methods are particularly important in modern neuro-oncology when a tumor affects eloquent language areas since damage to parts of the language circuits can cause significant impairments in daily life. This narrative review examines the literature regarding preoperative and intraoperative language mapping using repetitive navigated transcranial magnetic stimulation (rnTMS) with or without direct electrical stimulation (DES) in adult patients with tumors in eloquent language areas. The literature shows that rnTMS is accurate in detecting preexisting language disorders and positive intraoperative mapping regions. In terms of the region extent and clinical outcomes, rnTMS has been shown to be accurate in identifying positive sites to guide resection, reducing surgery duration and craniotomy size and thus improving clinical outcomes. Before incorporating rnTMS into the neurosurgical workflow, the refinement of protocols and a consensus within the neuro-oncology community are required.

5-ALA-guided tumor resection during awake speech mapping in gliomas located in eloquent speech areas: Single-center experience.

BackgroundAchieving maximal functionally safe resection of gliomas located within the eloquent speech areas is challenging, and there is a lack of literature on the combined use of 5-aminolevulinic acid (5-ALA) guidance and awake craniotomy.ObjectiveThe aim of this study was to describe our experience with the simultaneous use of 5-ALA fluorescence and awake speech mapping in patients with left frontal gliomas located within the vicinity of eloquent speech areas.Materials and methodsA prospectively collected database of patients was reviewed. 5-ALA was administered at a dose of 20 mg/kg 2 h prior to operation, and an operating microscope in BLUE400 mode was used to visualize fluorescence. All patients underwent surgery using the “asleep–awake–asleep” protocol with monopolar and bipolar electrical stimulation to identify the proximity of eloquent cortex and white matter tracts and to guide safe limits of resection along with fluorescence guidance. Speech function was assessed by a trained neuropsychologist before, during, and after surgery.ResultsIn 28 patients operated with cortical mapping and 5-ALA guidance (12 Grade 4, 6 Grade 3, and 10 Grade 2 gliomas), Broca’s area was identified in 23 cases and Wernicke’s area was identified in 5 cases. Fluorescence was present in 14 cases. Six tumors had residual fluorescence due to the positive speech mapping in the tumor bed. Transient aphasia developed in 14 patients, and permanent aphasia developed in 4 patients. In 6 patients operated with cortical and subcortical speech mapping and 5-ALA guidance (4 Grade 4, 1 Grade 3, and 1 Grade 2 gliomas), cortical speech areas were mapped in 5 patients and subcortical tracts were encountered in all cases. In all cases, resection was stopped despite the presence of residual fluorescence due to speech mapping findings. Transient aphasia developed in 6 patients and permanent aphasia developed in 4 patients. In patients with Grade 2–3 gliomas, targeted biopsy of focal fluorescence areas led to upgrading the grade and thus more accurate diagnosis.Conclusion5-ALA guidance during awake speech mapping is useful in augmenting the extent of resection for infiltrative high-grade gliomas and identifying foci of anaplasia in non-enhancing gliomas, while maintaining safe limits of functional resection based on speech mapping. Positive 5-ALA fluorescence in diffuse Grade 2 gliomas may be predictive of a more aggressive disease course.

More on the extension of linear operators on Riesz spaces

The classical Kantorovich theorem asserts the existence and uniqueness of a linear extension of a positive additive mapping, defined on the positive cone $E^+$ of a Riesz space $E$ taking values in an Archimedean Riesz space $F$, to the entire space $E$. We prove that, if $E$ has the principal projection property and $F$ is Dedekind $\sigma$-complete then for every $e \in E^+$ every positive finitely additive $F$-valued measure defined on the Boolean algebra $\mathfrak{F}_e$ of fragments of $e$ has a unique positive linear extension to the ideal $E_e$ of $E$ generated by $e$. If, moreover, the measure is $\tau$-continuous then the linear extension is order continuous.

Functional outcomes after resection of middle frontal gyrus diffuse gliomas.

The clinical outcomes for patients undergoing resection of diffuse glioma within the middle frontal gyrus (MFG) are understudied. Anatomically, the MFG is richly interconnected to known language areas, and nearby subcortical fibers are at risk during resection. The goal of this study was to determine the functional outcomes and intraoperative mapping results related to resection of MFG gliomas. Additionally, the study aimed to evaluate if subcortical tract disruption on imaging correlated with functional outcomes. The authors performed a retrospective review of 39 patients with WHO grade II-IV diffuse gliomas restricted to only the MFG and underlying subcortical region that were treated with resection and had no prior treatment. Intraoperative mapping results and postoperative neurological deficits by discharge and 90 days were assessed. Diffusion tensor imaging (DTI) tractography was used to assess subcortical tract integrity on pre- and postoperative imaging. The mean age of the cohort was 37.9 years at surgery, and the median follow-up was 5.1 years. The mean extent of resection was 98.9% for the cohort. Of the 39 tumors, 24 were left sided (61.5%). Thirty-six patients (92.3%) underwent intraoperative mapping, with 59% of patients undergoing an awake craniotomy. No patients had positive cortical mapping sites overlying the tumor, and 12 patients (33.3%) had positive subcortical stimulation sites. By discharge, 8 patients had language dysfunction, and 5 patients had mild weakness. By 90 days, 2 patients (5.1%) had persistent mild hand weakness only. There were no persistent language deficits by 90 days. On univariate analysis, preoperative tumor size (p = 0.0001), positive subcortical mapping (p = 0.03), preoperative tumor invasion of neighboring subcortical tracts on DTI tractography (p = 0.0003), and resection cavity interruption of subcortical tracts on DTI tractography (p < 0.0001) were associated with an increased risk of having a postoperative deficit by discharge. There were no instances of complete subcortical tract transections in the cohort. MFG diffuse gliomas may undergo extensive resection with minimal risk for long-term morbidity. Partial subcortical tract interruption may lead to transient but not permanent deficits. Subcortical mapping is essential to reduce permanent morbidity during resection of MFG tumors by avoiding complete transection of critical subcortical tracts.

Intraoperative neuromonitoring in surgery of supratentorial brain tumors. Part 1. Assessment of motor conductivity

Monitoring of motor evoked potentials in surgery of supratentorial tumors estimates integrity of cortical motor centers and subcortical pathways. Violation of motor evoked potentials takes place in mechanical injury or ischemia of motor neurons. Decrease of amplitude of motor evoked potentials more than 50 % is predictor of permanent neurological deficit.Cortical mapping gives a possibility to discover eloquent brain areas before their resection. To reveal motor centers activating stimulation is applied, to find out speech or sensory areas – the inhibiting one. Positive brain mapping allows to exclude technical fault in selection of stimulation threshold but it demands a wide craniotomy. Negative mapping is more widespread, gives opportunity to use tailored craniotomy that reduces surgical injury and duration of operation. One of the most valuable factors in cortical and subcortical brain mapping is the stimulation threshold. With monopolar «train» stimulation current 1 mA spreads into approximately 1 mm. The safe value of current intensity during tumor resection in eloquent areas is 3–5 mA.Monopolar stimulation demands less time for location of eloquent brain areas, it is as accurate as the bipolar mapping and more rarely leads to intraoperative seizures. Combination of monopolar stimulator with aspirator gives opportunity to continuously allocate pyramidal tract in tumor resection.

Evaluation of methods to detect circular RNAs from single-end RNA-sequencing data

BackgroundCircular RNA (circRNA), a class of RNA molecule with a loop structure, has recently attracted researchers due to its diverse biological functions and potential biomarkers of human diseases. Most of the current circRNA detection methods from RNA-sequencing (RNA-Seq) data utilize the mapping information of paired-end (PE) reads to eliminate false positives. However, much of the practical RNA-Seq data such as cross-linking immunoprecipitation sequencing (CLIP-Seq) data usually contain single-end (SE) reads. It is not clear how well these tools perform on SE RNA-Seq data.ResultsIn this study, we present a systematic evaluation of six advanced RNA-based methods and two CLIP-Seq based methods for detecting circRNAs from SE RNA-Seq data. The performances of the methods are rigorously assessed based on precision, sensitivity, F1 score, and true discovery rate. We investigate the impacts of read length, false positive ratio, sequencing depth and PE mapping information on the performances of the methods using simulated SE RNA-Seq simulated datasets. The real datasets used in this study consist of four experimental RNA-Seq datasets with ≥100bp read length and 124 CLIP-Seq samples from 45 studies that contain mostly short-read (≤50bp) RNA-Seq data. The simulation study shows that the sensitivities of most of the methods can be improved by increasing either read length or sequencing depth, and that the levels of false positive rates significantly affect the precision of all methods. Furthermore, the PE mapping information can improve the method’s precision but can not always guarantee the increase of F1 score. Overall, no method is dominant for all SE RNA-Seq data. The RNA-based methods perform better for the long-read datasets but are worse for the short-read datasets. In contrast, the CLIP-Seq based methods outperform the RNA-Seq based methods for all the short-read samples. Combining the results of these methods can significantly improve precision in the CLIP-Seq data.ConclusionsThe results provide a systematic evaluation of circRNA detection methods on SE RNA-Seq data that would facilitate researchers’ strategies in circRNA analysis.

Two different subcortical language networks supporting distinct Japanese orthographies: morphograms and phonograms.

Language systems worldwide are based on either morphograms or phonograms, but Japanese is unique in that uses a complicated combination of kanji (morphogram) and kana (phonogram) characters. The white matter networks associated with reading have been investigated previously but remain incompletely understood. In this study, we performed intraoperative language mapping under local anesthesia and postoperative language assessments of 53 consecutive patients who underwent awake craniotomy for surgical resection of cerebral glioma within the dominant temporal or parietal lobe. Six cases showing intraoperative dyslexia elicited by direct electrical stimulation (DES) were examined, and all cases showed transient symptoms of kanji or kana dyslexia during DES. We investigated the intraoperative positive mapping points localized near four white matter bundles: the arcuate fascicle, posterior superior longitudinal fascicle, inferior fronto-occipital longitudinal fascicle, and inferior longitudinal fascicle (ILF). The intraoperative DES distributions for kanji dyslexia were especially associated with the anterior-inferior side of the ILF. On the other hand, the DES points associated with kana dyslexia were localized on the posterior-superior side of the complex composed of these four tracts. These results suggest the presence of specific non-interfering networks that subserve the processes of reading morphograms and phonograms.