Temporal lobe epilepsy causes severe cognitive deficits, but the circuit mechanisms remain unknown. Interneuron death and reorganization during epileptogenesis may disrupt the synchrony of hippocampal inhibition. To test this, we simultaneously recorded from the CA1 and dentate gyrus in pilocarpine-treated epileptic mice with silicon probes during head-fixed virtual navigation. We found desynchronized interneuron firing between the CA1 and dentate gyrus in epileptic mice. Since hippocampal interneurons control information processing, we tested whether CA1 spatial coding was altered in this desynchronized circuit, using a novel wire-free miniscope. We found that CA1 place cells in epileptic mice were unstable and completely remapped across a week. This spatial instability emerged around 6 weeks after status epilepticus, well after the onset of chronic seizures and interneuron death. Finally, CA1 network modeling showed that desynchronized inputs can impair the precision and stability of CA1 place cells. Together, these results demonstrate that temporally precise intrahippocampal communication is critical for spatial processing. David Geffen School of Medicine Dean's Fund for development of open-source miniaturized microscopes to B.

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OBJECTIVEFrailty has been recognized as a predictor of adverse surgical outcomes across multiple surgical disciplines, but until now the relationship between frailty and intracranial meningioma surgery has not been studied. The goal of the present study was to determine the relationship between increasing frailty (determined using the modified Frailty Index [mFI]) and intracranial meningioma resection outcomes (including hospital length of stay [LOS], discharge location, and reoperation and readmission rates).METHODSThis is a single-center retrospective cohort study of patients who underwent intracranial meningioma resection between August 2012 and May 2018. Seventy-six patients met the inclusion criteria.RESULTSFrailty was associated with increased hospital LOS (p = 0.0218), increased reoperation rate (p = 0.029), and discharge to a higher level of care: an inpatient rehabilitation facility or a skilled nursing facility (p = 0.0002). After multivariable analysis, frailty was determined to be an independent risk factor for increased LOS, worse discharge disposition, and subsequent readmission.CONCLUSIONSFrailty is an independent risk factor for worse outcomes following intracranial meningioma resection, including increased LOS, reoperations, and worse discharge disposition. Frailty may help stratify preoperative surgical risk, and thus may provide important clinical information to help neurosurgeons and elderly patients weigh the risks and benefits of resection.

Background Women have long been underrepresented in orthopaedic surgery; however, there is a lack of quantitative data on the representation of women in orthopaedic academic program leadership. Questions/purposes (1) What is the proportion of women in leadership roles in orthopaedic surgery departments and residency programs in the United States (specifically, chairs, vice chairs, program directors, assistant program directors, and subspecialty division chiefs)? (2) How do women and men leaders compare in terms of years in position in those roles, years in practice, academic rank, research productivity as represented by publications, and subspecialty breakdown? (3) Is there a difference between men and women in the chair or program director role in terms of whether they are working in that role at institutions where they attended medical school or completed their residency or fellowship? Methods We identified 161 academic orthopaedic residency programs from the Accreditation Council for Graduate Medical Education (ACGME) website. Data (gender, length of time in position, length of time in practice, professorship appointment, research productivity as indirectly measured via PubMed publications, and subspecialty) were collected for chairs, vice chairs, program directors, assistant program directors, and subspecialty division chiefs in July 2020 to control for changes in leadership. Information not provided by the ACGME and PubMed was found using orthopaedic program websites and the specific leader's curriculum vitae. Complete data were obtained for chairs and program directors, but there were missing data points for vice chairs, assistant program directors, and division chiefs. All statistical analysis was performed using SPSS using independent t-tests for continuous variables and the Pearson chi-square test for categorical variables, with p < 0.05 considered significant. Results Three percent (4 of 153) of chairs, 8% (5 of 61) of vice chairs, 11% (18 of 161) of program directors, 27% (20 of 75) of assistant program directors, and 9% (45 of 514) of division chiefs were women. There were varying degrees of missing data points for vice chairs, assistant program directors, and division chiefs as not all programs reported or have those positions. Women chairs had fewer years in their position than men (2 6 1 versus 9 6 7 [95% confidence interval -9.3 to -5.9]; p < 0.001). Women vice chairs more commonly specialized in hand or tumor compared with men (40% [2 of 5] and 40% [2 of 5] versus 11% [6 of 56] and 4% [2 of 56],Each author certifies that there are no funding or commercial associations (consultancies, stock ownership, equity interest, patent/licensing arrangements, etc.) that might pose a conflict of interest in connection with the submitted article related to the author or any immediate family members. All ICMJE Conflict of Interest Forms for authors and Clinical Orthopaedics and Related Research® editors and board members are on file with the publication and can be viewed on request. Ethical approval was not sou...