Thursday, January 27, 2022

A structured ICA-based process for removing auditory evoked potentials

xlomafota13 shared this article with you from Inoreader

Sci Rep. 2022 Jan 26;12(1):1391. doi: 10.1038/s41598-022-05397-3.

ABSTRACT

Transcranial magnetic stimulation (TMS)-evoked potentials (TEPs), recorded using electroencephalography (EEG), reflect a combination of TMS-induced cortical activity and multi-sensory responses to TMS. The auditory evoked potential (AEP) is a high-amplitude sensory potential-evoked by the "click" sound produced by every TMS pulse-that can dominate the TEP and obscure observation of other neural components. The AEP is peripherally evoked and therefore should not be stimulation site specific. We address the problem of disentangling the peripherally evoked AEP of the TEP from components evoked by cortical stimulation and ask whether removal of AEP enables more accurate isolation of TEP. We hypothesized that isolation of the AEP using Independent Components Analysis (ICA) would reveal features that are stimulation site specific and unique individual features. In order to i mprove the effectiveness of ICA for removal of AEP from the TEP, and thus more clearly separate the transcranial-evoked and non-specific TMS-modulated potentials, we merged sham and active TMS datasets representing multiple stimulation conditions, removed the resulting AEP component, and evaluated performance across different sham protocols and clinical populations using reduction in Global and Local Mean Field Power (GMFP/LMFP) and cosine similarity analysis. We show that removing AEPs significantly reduced GMFP and LMFP in the post-stimulation TEP (14 to 400 ms), driven by time windows consistent with the N100 and P200 temporal characteristics of AEPs. Cosine similarity analysis supports that removing AEPs reduces TEP similarity between subjects and reduces TEP similarity between stimulation conditions. Similarity is reduced most in a mid-latency window consistent with the N100 time-course, but nevertheless remains high in this time window. Residual TEP in this window has a time-c ourse and topography unique from AEPs, which follow-up exploratory analyses suggest could be a modulation in the alpha band that is not stimulation site specific but is unique to individual subject. We show, using two datasets and two implementations of sham, evidence in cortical topography, TEP time-course, GMFP/LMFP and cosine similarity analyses that this procedure is effective and conservative in removing the AEP from TEP, and may thus better isolate TMS-evoked activity. We show TEP remaining in early, mid and late latencies. The early response is site and subject specific. Later response may be consistent with TMS-modulated alpha activity that is not site specific but is unique to the individual. TEP remaining after removal of AEP is unique and can provide insight into TMS-evoked potentials and other modulated oscillatory dynamics.

PMID:35082350 | DOI:10.1038/s41598-022-05397-3

View on the web

Modulation Depth Discrimination by Cochlear Implant Users

xlomafota13 shared this article with you from Inoreader

Abstract

Cochlear implants (CIs) convey the amplitude envelope of speech by modulating high-rate pulse trains. However, not all of the envelope may be necessary to perceive amplitude modulations (AMs); the effective envelope depth may be limited by forward and backward masking from the envelope peaks. Three experiments used modulated pulse trains to measure which portions of the envelope can be effectively processed by CI users as a function of AM frequency. Experiment 1 used a three-interval forced-choice task to test the ability of CI users to discriminate less-modulated pulse trains from a fully modulated standard, without controlling for loudness. The stimuli in experiment 2 were identical, but a two-interval task was used in which participants were required to choose the less-modulated interval, ignoring loudness. Catch trials, in which judgements based on level or modulation depth would give opposing answers, were included. Experiment 3 employed novel stimuli whose modulation envelope could be modified below a variable point in the dynamic range, without changing the loudness of the stimulus. Overall, results showed that substantial portions of the envelope are not accurately encoded by CI users. In experiment 1, where loudness cues were available, participants on average were insensitive to changes in the bottom 30% of their dynamic range. In experiment 2, where loudness was controlled, participants appeared insensitive to changes in the bottom 50% of the dynamic range. In experiment 3, participants were insensitive to changes in the bottom 80% of the dynamic range. We discuss potential reasons for this insensitivity and implications for CI speech-processing strategies.

View on the web

Association of Cigarette Smoking With Audiometric Hearing Impairment and Speech-in-Noise Perception

xlomafota13 shared this article with you from Inoreader

ooi210078f1_1642608500.08915.png?Expires

This cross-sectional study assesses data from the Atherosclero sis Risk in Communities Study to examine whether long-term smoking behavior patterns are associated with worse measures of hearing loss in older adults.
View on the web

A dose-neutral image quality comparison of different CBCT and CT systems using paranasal sinus imaging protocols and phantoms

xlomafota13 shared this article with you from Inoreader

Eur Arch Otorhinolaryngol. 2022 Jan 27. doi: 10.1007/s00405-022-07271-4. Online ahead of print.

ABSTRACT

PURPOSE: To compare the image quality produced by equivalent low-dose and default sinus imaging protocols of a conventional dental cone-beam computed tomography (CBCT) scanner, an extremity CBCT scanner and a clinical multidetector computed tomography (MDCT) scanner.

METHODS: Three different phantoms were scanned using dose-neutral ultra-low-dose and low-dose sinus imaging protocols, as well as default sinus protocols of each device. Quantified parameters of image quality included modulation transfer function (MTF) to characterize the spatial response of the imaging system, contrast-to-noise ratio, low contrast visibility, image uniformity and Hounsfield unit accuracy. MTF was calculated using the line spread and edge spread functions (LSF and ESF).

RESULTS: The dental CBCT had superior performance over the extremity CBC T in each studied parameter at similar dose levels. The MDCT had better contrast-to-noise ratio, low contrast visibility and image uniformity than the CBCT scanners. However, the CBCT scanners had better resolution compared to the MDCT. Accuracy of HU values for different materials was on the same level between the dental CBCT and MDCT, but substantially poorer performance was observed with the extremity CBCT.

CONCLUSIONS: The studied dental CBCT scanner showed superior performance over the studied extremity CBCT scanner when using dose-neutral imaging protocols. In case a dental CBCT is not available, the given extremity CBCT is still a viable option as it provides the benefit of high resolution over a conventional MDCT.

PMID:35084532 | DOI:10.1007/s00405-022-07271-4

View on the web

Comparison of Outcomes of Surgical Repair of Spontaneous Temporal Bone CSF Leaks and Encephaloceles Using Bone Cement and Autologous Material

xlomafota13 shared this article with you from Inoreader

Otol Neurotol. 2022 Jan 27. doi: 10.1097/MAO.0000000000003467. Online ahead of print.

ABSTRACT

OBJECTIVE: To compare outcomes transmastoid repair of spontaneous middle fossa cerebrospinal fluid (CSF) leak using only bone cement (BC) versus only autologous material (AM) or combined materials (CM) with both bone cement and autologous material.

STUDY DESIGN: Retrospective Chart Review.

SETTING: Tertiary Care Hospital.

PATIENTS: Forty-three adult patients undergoing transmastoid repair of spontaneous middle fossa CSF leak between 2014 and 2020 (BC:12, AM:15, CR:16).

INTERVENTIONS: Cortical mastoidectomy, identification of defect, and repair with BC (Cranios® hydroxyapatite), AM (local bone, fascia, fat, and/or cartilage), or CM (Cranios® combined with autologous materials).

MAIN OUTCOME MEASURES: Successful repair without recurrent CSF leak or encephalocele throughout follow up.

RESULTS: Fifty-one percent of subjects were female. Mean age at repair was 58.6 years (SD 10.9). Mean BMI was 35.4 (SD 7.6; BC:36.3, AM:36.5, CM:33.6). Forty (93%) patients had successful repair without known recurrent CSF leak or encephalocele since surgery (BC:11, 91.6%; AM:14, 93.3%; CM:15, 93.8%; p = 0.49) over a mean length of follow up of 49.6 months (BC: 37.9, AM: 59.2, CR: 49.5). The difference in mean operative time amongst the groups was faster for patients using bone cement (BC: 100.2 min, AM: 182.8, CM: 133.2; p < 0.00001).

CONCLUSIONS: BC, AM, and CM techniques each demonstrate effective and sustained means of repair for middle fossa CSF leak and encephalocele, even in the presence of multiple defects. Use of isolated BC offers a significant decrease in operative time with a noninferior outcome. Active CSF leak at the time of surgery is associated with increased risk of recurrence.

PMID:35085113 | DOI:10.1097/MAO.0000000000003467

View on the web

Wednesday, January 26, 2022

Outcomes in surgical management of sinonasal malignancy—A single comprehensive cancer center experience

xlomafota13 shared this article with you from Inoreader

Abstract

Background

Sinonasal malignancies are a complex and diverse group of tumors. Over the past five decades, treatment advances have changed the management paradigms for these tumors. Our aim was to analyze the outcomes of patients from a comprehensive cancer center.

Materials and Methods

We retrospectively assessed 400 patients with sinonasal malignancies treated with surgery at our center between 1973 and 2015. Multiple variables were reviewed to assess the influence on 5-year outcomes.

Results

The median age was 56 years (IQR 46.8–68). Two hundred and fifty-nine (65%) were males and 141 (35%) were females. Overall survival (OS) and disease-specific survival (DSS) improved in the last analyzed decade. Orbital invasion, advanced pT-classification and pN-classification, and melanoma histology were associated with poorer outcomes.

Conclusion

Treatment outcomes for patients with sinonasal malignancy have improved over time. This is likely multifactorial with advances in surgical technique, adjuvant treatment, and patient selection. pT-classification, pN-classification, orbital invasion, and histology are predictive of survival.

View on the web

Sensitizing TRAIL response via differential modulation of anti- and pro-apoptotic factors by AZD5582 combined with ER nanosomal TRAIL in neuroblastoma

xlomafota13 shared this article with you from Inoreader
Via histochem

pubmed-meta-image.png

Acta Histochem. 2022 Jan 22;124(2):151856. doi: 10.1016/j.acthis.2022.151856. Online ahead of print.

ABSTRACT

Neuroblastoma is a metastatic brain tumor particularly common in children. The cure rate is below 50% for patients of high-risk condition. Novel therapeutic agents and approaches are needed to improve the cure rate. Tumor necrosis factor-related and apoptosis-inducing ligand (TRAIL) is a promising proapoptotic factor that rapidly induces apoptosis preferentially in t ransformed and cancerous cells. Unfortunately, the common TRAIL resistance in cancers has hampered the clinical application of the ligand. Previously we prepared a novel TRAIL-armed ER derived nanosomal agent (ERN-T) that overcomes TRAIL resistance in some cancer lines when combined with a synthetic antagonist of inhibitors of apoptosis proteins (IAPs), AZD5582. However, how AZD5582 sensitizes cancer cells to ERN-T remains not well understood. In this study we continued to test the therapeutic efficacy of the combinatory therapy of ERN-T and AZD5582 on neuroblastoma, aiming to reveal the molecular mechanism underlying the synergism between AZD5582 and ERN-T. The obtained data revealed that ERN-Ts overcame TRAIL resistance and showed significant cytotoxicity on the resistant neuroblastoma line SH-SH5Y when combined with AZD5582 whilst sparing normal cells. The combination of low doses of ERN-Ts and AZD5582 induced intensive apoptosis in SH-SY5Y but not in normal skin fibroblasts (NSF s). Importantly we discovered that TRAIL sensitization in SH-SY5Y was associated with the concomitant downregulation of antiapoptotic factors cFLIP, MCL-1 and IAPs and upregulation of proapoptotic protein BAX and the death receptor 5 (DR5) by the cotreatment of ERN-T and AZD5582. In vivo study demonstrated that the combination of ERN-T and AZD5582 constituted a highly effective and safe therapy for subcutaneous SH-SY5Y xenograft neuroblastoma in nude mice. In conclusion, we identified that the concomitant regulation of both antiapoptotic and proapoptotic factors and DR5 is an essential molecular mechanism for overcoming TRAIL resistance in SH-SY5Y and the combination of ERN-T and AZD5582 potentially constitutes a novel therapeutic strategy, which is highly effective and safe for neuroblastoma.

PMID:35077998 | DOI:10.1016/j.acthis.2022.151856

View on the web

Objective evaluation of stimulation artefact removal techniques in the context of neural spike sorting

xlomafota13 shared this article with you from Inoreader

J Neural Eng. 2022 Jan 25. doi: 10.1088/1741-2552/ac4ecf. Online ahead of print.

ABSTRACT

Objective - We present a framework to objectively test and compare stimulation artefact removal techniques in the context of neural spike sorting. Approach - To this end, we used realistic hybrid ground-truth spiking data, with superimposed artefacts from in vivo recordings. We used the framework to evaluate and compare several techniques: blanking, template subtraction by averaging, linear regression, and a multi-channel Wiener filter (MWF). Main results - Our study demonstrates that blanking and template subtraction result in a poorer spike sorting performance than linear regression and MWF, while the latter two perform similarly. Finally, to validate the conclusions found from the hybrid evaluation framework, we also performed a qualitative analysis on in vivo recordings without artificial manipulations. Significance - Our framework allows direct quan tification of the impact of the residual artefact on the spike sorting accuracy, thereby allowing for a more objective and more relevant comparison compared to indirect signal quality metrics that are estimated from the signal statistics. Furthermore, the availability of a ground truth in the form of single-unit spiking activity also facilitates a better estimation of such signal quality metrics.

PMID:35078163 | DOI:10.1088/1741-2552/ac4ecf

View on the web

Chinese guidelines for diagnosis and treatment of allergic rhinitis (2022, revision)

xlomafota13 shared this article with you from Inoreader

Zhonghua Er Bi Yan Hou Tou Jing Wai Ke Za Zhi. 2022 Jan 21;57:8-31. doi: 10.3760/cma.j.cn115330-20211228-00828. Online ahead of print.

NO ABSTRACT

PMID:35078291 | DOI:10.3760/cma.j.cn115330-20211228-00828

View on the web

Chemosaturation with percutaneous hepatic perfusion of melphalan for metastatic uveal melanoma

xlomafota13 shared this article with you from Inoreader

SocialThumb.00008390.DC.jpeg

Purpose Uveal melanoma, the most common primary ocular malignancy in adults, carries a poor prognosis: 50% of patients develop the metastatic disease with a 10–25% 1-year survival and no established standard of care treatment. Prior studies of melphalan percutaneous hepatic perfusion (M-PHP) have shown promise in metastatic uveal melanoma (mUM) patients with liver predominant disease but are limited by small sample sizes. We contribute our findings on the safety and efficacy of the procedure in the largest sample population to date. Patients and methods retrospective analysis of outcome and safety data for all mUM patients receiving M-PHP was performed. Tumour response and treatment toxicity were evaluated using RECIST 1.1 and Common Terminology Criteria for Adverse Events v5.03, respectively. Results 250 M-PHP procedures were performed in 81 patients (median of three per patient). The analysis demonstrated a hepatic disease control rate of 88.9% (72/81), a hepatic response rate of 66.7% (54/81), and an overall response rate of 60.5% (49/81). After a median follow-up of 12.9 months, median overall progression-free (PFS) and median overall survival (OS) were 8.4 and 14.9 months, respectively. There were no fatal treatment-related adverse events (TRAE). Forty-three grade 3 (29) or 4 (14) TRAE occurred in 23 (27.7%) patients with a significant reduction in such events between procedures performed in 2016–2020 vs. 2012–2016 (0.17 vs. 0.90 per patient, P
View on the web

Endoscopic Posterior Rotation Flap for Posterior Glottic Insufficiency

xlomafota13 shared this article with you from Inoreader
View on the web

Collaboration request

Hi there How would you like to earn a 35% commission for each sale for life by selling SEO services Every website owner requires the ...