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Growing evidence suggests that cerebral connectivity changes its network organization by altering modular topology in response to developmental and environmental experience. However, changes in cerebral connectivity associated with visual impairment due to early neurological injury are still not fully understood. Cerebral visual impairment (CVI) is a brain-based visual disorder associated with damage and maldevelopment of retrochiasmal pathways and areas implicated in visual processing. In this study, we used a multimodal imaging approach and connectomic analyses based on structural (voxel-based morphometry; VBM) and resting state functional connectivity (rsfc) to investigate differences in weighted degree and link-level connectivity in individuals with CVI compared to controls with neurotypical development. We found that participants with CVI showed significantly reduced grey matter volume within the primary visual cortex and intraparietal sulcus (IPS) compared to controls. Participants with CVI also exhibited marked reorganization characterized by increased integration of visual connectivity to somatosensory and multimodal integration areas (dorsal and ventral attention regions) and lower connectivity from visual to limbic and default mode networks. Link-level functional changes in CVI were also associated with key clinical outcomes related to visual function and development. These findings provide early insight into how visual impairment related to early brain injury distinctly reorganizes the functional network architecture of the human brain., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: Numerous, sometimes conflicting, changes in brain functional connectivity have been associated with the transition from wakefulness to unresponsiveness at induction of general anesthesia. However, relatively few studies have looked at: the detailed time evolution of the transition; for different EEG frequency bands; and in the clinical scenario of surgical patients undergoing general anesthesia., Methods: We investigated the changes in the frontal and fronto-parietal directed and undirected functional connectivity to multichannel EEG data recorded from 29 adult male surgical patients undergoing propofol-induced loss of consciousness during induction of anesthesia. Directed functional connectivity was estimated using bivariate frequency domain Granger causality, and undirected connectivity was assessed using EEG coherence., Results: Around the point of loss of consciousness: local frontal, interhemispheric frontal, and frontoparietal feedback and feedforward Granger causality all decreased between 31% and 51.5% in the delta-band (median [interquartile range] for local frontal: 0.14 [0.08, 0.27] to 0.08 [0.06, 0.12] (p=0.02)). After a lag of a few minutes, Granger Causality markedly increased in the gamma and beta bands for local frontal (0.03 [0.02, 0.07] to 0.09 [0.07, 0.11](p<0.001)) and long-distance cross-hemispheric frontoparietal feedback (0.02 [0.01, 0.04] to 0.07 [0.04, 0.09], p<0.001) and feedforward (0.02 [0.01, 0.04] to 0.03 [0.03, 0.04], p=0.01) coupling; but not for within-hemispheric frontoparietal feedback and feedforward. Frontal interhemispheric EEG coherence significantly decreased in the lower frequencies (f<12Hz) at loss of consciousness, while no significant increase for the beta and gamma bands was observed., Conclusions: Propofol-induced loss of consciousness in surgical patients is associated with a global breakdown in low-frequency directed functional connectivity, coupled with a high-frequency increase between closely located brain regions. At loss of consciousness, Granger causality shows more pronounced changes than coherence., Competing Interests: Conflicts of Interest: Drs. Kreuzer and Garcia are named as inventors for a patent recently filed on a method for intraoperative EEG monitoring that accounts for spectral and entropic features of age (System, method and computer-accessible medium which takes into consideration the change(s) of spectral and entropic features age in the electroencephalogram in patients under sevoflurane anesthesia; U.S. Provisional Patent Application No. 62/914,183 filed on October 11, 2019). Drs Schneider, García, and Kreuzer are named as inventors for a patent filed on a novel method for intraoperative EEG monitoring (System, method and computer-accessible medium for anesthesia monitoring using electroencephalographic monitoring; U.S. Patent Application Serial No. 62/960,947; filed on January 14, 2020). Dr. García is a co-founder of a company, Lantern Laboratories, Inc. that has a license to build software and hardware for intraoperative monitoring. Dr. Kreuzer received financial support from Medtronic to hold the SBI EEG Bootcamp., (Copyright © 2024 American Society of Anesthesiologists. All Rights Reserved.)

Aims: Lichen sclerosus (LS) is a chronic inflammatory disease of the genital skin of unknown aetiology. The role of LS in penile squamous cell carcinogenesis is not well characterized. HPV has been implicated in both, as have epigenetic changes. The presence of HPV and hypermethylation of the MGMT, p16, RASSF1, RASSF2, TSLC1 and TSP1 genes were studied in penile LS; MGMT, RASSF2 and TSLC1 hypermethylation in penile cancer and TSLC1 hypermethylation in vulvar LS and cancer extends previous results reported by our group., Methods and Results: Thirty-seven HPV genotypes and hypermethylation were evaluated by PCR/reverse-line-blot and methylation-specific PCR respectively, in 27 preputial LS, 24 penile SCC, 30 vulvar SCC, 21 vulvar LS and 22 normal skin cases. HPV66 was present in 3.7% of penile LS cases, and p16 and RASSF2 hypermethylation were more frequent in penile cancer than in penile LS. p16, RASSF1, RASSF2 and TSP1 hypermethylation were similar in penile and vulvar LS., Conclusions: Gene hypermethylation is a common event in penile LS, and occurs approximately as frequently as in vulvar LS. Certain genes can be hypermethylated as an early or late event in LS or cancer, respectively. This suggests a possible sequential role for these alterations in the transition from benign to malignant lesions., (© 2013 John Wiley & Sons Ltd.)