Cell-free formation of RNA granules: low complexity sequence domains form dynamic fibers within hydrogels.

Eukaryotic cells contain assemblies of RNAs and proteins termed RNA granules. Many proteins within these bodies contain KH or RRM RNA-binding domains as well as low complexity (LC) sequences of unknown function. We discovered that exposure of cell or tissue lysates to a biotinylated isoxazole (b-isox) chemical precipitated hundreds of RNA-binding proteins with significant overlap to the constituents of RNA granules. The LC sequences within these proteins are both necessary and sufficient for b-isox-mediated aggregation, and these domains can undergo a concentration-dependent phase transition to a hydrogel-like state in the absence of the chemical. X-ray diffraction and EM studies revealed the hydrogels to be composed of uniformly polymerized amyloid-like fibers. Unlike pathogenic fibers, the LC sequence-based polymers described here are dynamic and accommodate heterotypic polymerization. These observations offer a framework for understanding the function of LC sequences as well as an organizing principle for cellular structures that are not membrane bound.

Tympanomastoidectomy versus parenteral antibiotic therapy for pediatric otorrhea.

OBJECTIVE: To evaluate the efficacy of tympanomastoidectomy versus parenteral antibiotic therapy for otorrhea as a result of chronic suppurative otitis media (CSOM) without cholesteatoma in the pediatric population. METHODS: A retrospective review of 221 patients treated for otorrhea at a tertiary academic pediatric hospital was performed to evaluate the impact of tympanomastoidectomy versus parenteral antibiotic therapy on resolution of otorrhea. Inclusion criteria were age 0-18 years, prior treatment with otic and/or oral antibiotic, prior history of tympanostomy tube placement for recurrent otitis media, history of otorrhea, treatment with tympanomastoidectomy or parenteral antibiotic therapy, and follow-up of at least 1 month after intervention. Time to resolution was compared between the two modalities adjusting for age, bilateral ear disease status, and comorbidities using a Cox proportional hazard model. RESULTS: Eighty-three ears from 58 children met the inclusion criteria. Ears that initially underwent tympanomastoidectomy had a significantly shorter time to resolution of symptoms (median time to resolution) 9 months (95 % confidence interval CI: 6.2-14.8) vs. 48.5 months (95 % lower CI 9.4, p = 0.006). On multivariate analysis, however, only bilateral ear disease status was independently associated with time to resolution of symptoms (hazard ratio 0.4, 95 % CI 0.2-0.9, p = 0.03). There was no statistically significant difference in the rate of treatment-related complications when comparing tympanomastoidectomy to parenteral antibiotic therapy (p = 0.37). CONCLUSION: When adjusting for age, bilateral ear disease status, and comorbidities, there does not appear to be a significant difference in time to resolution of symptoms when comparing parenteral antibiotic therapy to tympanomastoidectomy. An informed discussion regarding risks and benefits of each approach should be employed when deciding on the next step in management for patients with CSOM who have failed more conservative therapies.

Outcomes of Squamous Cell Carcinoma of the Lip Treated With Mohs Micrographic Surgery: A Retrospective Cohort Study.

BACKGROUND: Cutaneous squamous cell carcinomas (cSCCs) of the lip have been reported to be at higher risk for poorer post-treatment outcomes. OBJECTIVE: To examine outcomes of patients with SCC of the lip treated with Mohs micrographic surgery (MMS) and identify factors for recurrence. MATERIALS AND METHODS: This retrospective review of a single tertiary referral center's Mohs case logs from 2010 to 2019 identified cases of lip SCC. Clinicopathologic characteristics and outcomes (local recurrence [LR], metastasis, and disease-specific death) were reviewed. RESULTS: One hundred ninety cases of SCC of the lip were identified and demonstrated that MMS offered a disease-free survival of 96.8% over an average follow-up period of 42 months. Younger age (61 vs 74 years p = .006), increased MMS stages ( p = .009), and higher American Joint Committee on Cancer and Brigham and Women's Hospital T stages were risk factors for LR. Immunosuppression, large tumor size, mucosal lip involvement, aggressive histology, and perineural invasion were not associated with LR. CONCLUSION: The results of this study show that SCC of the lip behaved similarly to cSCC outside the lip area, and that both primary and recurrent lesions can be treated effectively with MMS.

A Call to Evaluate Manual Dexterity of Prospective Surgical Trainees.

INTRODUCTION: This study assesses the correlation between academic grades and gross and fine motor skills in prospective surgical trainees. METHODS: Forty-seven General Surgery Residency applicants and 32 medical students with prospective surgical interests were recruited. Manual dexterity (MD) was assessed through six tasks: O'Connor Tweezer Dexterity Test and Minnesota Manual Dexterity Test; Peg Transfer Test Fundamentals of Laparoscopic Surgery (box); Ring and Rail, Thread the Ring and Suture Sponge (da Vinci Surgical Simulator). RESULTS: Medical students with higher academic scores had longer completion times for the peg transfer test (P = 0.013). Individuals who played musical instruments and perceived themselves to have "Excellent" MD and motor coordination (MC) were more likely to score higher on the Thread the Ring test (P = 0.007; P = 0.009 ,respectively). Those who perceived themselves to have "Mediocre" MD and MC performed the worst on the: O'Connor Tweezer Dexterity Test (P = 0.023). CONCLUSIONS: Preliminary data suggest that MD ability correlates with neither high United States Medical Licensing Examination scores nor high academic grades; however, previous experience playing a musical instrument and high self-ratings of MD/MC may be associated with better test performance.

GenomeDiver: a platform for phenotype-guided medical genomic diagnosis.

PURPOSE: Making a diagnosis from clinical genomic sequencing requires well-structured phenotypic data to guide genotype interpretation. A patient's phenotypic features can be documented using the Human Phenotype Ontology (HPO), generating terms used to prioritize genes potentially causing the patient's disease. We have developed GenomeDiver to provide a user interface for clinicians that allows more effective collaboration with the clinical diagnostic laboratory, with the goal of improving the success of the diagnostic process. METHODS: GenomeDiver uses genomic data to prompt reverse phenotyping of patients undergoing genetic testing, enriching the amount and quality of structured phenotype data for the diagnostic laboratory, and helping clinicians to explore and flag diseases potentially causing their patient's presentation. RESULTS: We show how GenomeDiver communicates the clinician's informed insights to the diagnostic lab in the form of HPO terms for interpretation of genomic sequencing data. We describe our user-driven design process, the engineering of the software for efficiency, security and portability, and examples of the performance of GenomeDiver using genomic testing data. CONCLUSION: GenomeDiver is a first step in a new approach to genomic diagnostics that enhances laboratory-clinician interactions, with the goal of directly engaging clinicians to improve the outcome of genomic diagnostic testing.

Challenges of drug development during the COVID-19 pandemic: Key considerations for clinical trial designs.

There is an urgent need for targeted and effective COVID-19 treatments. Several medications, including hydroxychloroquine, remdesivir, lopinavir-ritonavir, favipiravir, tocilizumab and others have been identified as potential treatments for COVID-19. Bringing these repurposed medications to the public for COVID-19 requires robust and high-quality clinical trials that must be conducted under extremely challenging pandemic conditions. This article reviews translational science principles and strategies for conducting clinical trials in a pandemic and evaluates recent trials for different drug candidates. We hope that this knowledge will help focus efforts during this crisis and lead to the expedited development and approval of COVID-19 therapies.

A Cross-Sectional Study of Caregiver Perceptions of Congenital Cytomegalovirus Infection: Knowledge and Attitudes about Screening.

OBJECTIVES: To understand caregiver knowledge of and attitudes toward congenital cytomegalovirus (cCMV) testing in Utah. STUDY DESIGN: We surveyed 365 caregivers whose children were being seen in an otolaryngology clinic at a tertiary pediatric hospital about their knowledge of and attitudes toward cCMV and cCMV screening. Descriptive statistics and cluster analysis were used to examine their responses. RESULTS: The majority of caregivers were unsure how cCMV was spread, the symptoms of cCMV, and why cCMV screening of infants was important. Most caregivers did not know that cCMV screening was required by law in Utah if an infant is referred after newborn hearing screening. A majority wanted to know if their child had cCMV even if asymptomatic and were willing to pay $20 for cCMV screening. Caregivers of children who had been tested for cCMV were significantly more likely to be strongly in favor of cCMV screening than expected by chance. Caregivers in the highly knowledgeable cluster were more likely to be strongly in favor of cCMV screening. CONCLUSIONS: Caregivers frequently were unaware of cCMV and its implications. Attitudes toward cCMV screening generally were positive. Education on epidemiology and impact of cCMV may benefit both prevention of infection and attitudes toward screening.

Toxic PRn poly-dipeptides encoded by the C9orf72 repeat expansion block nuclear import and export.

The toxic proline:arginine (PRn) poly-dipeptide encoded by the (GGGGCC)n repeat expansion in the C9orf72 form of heritable amyotrophic lateral sclerosis (ALS) binds to the central channel of the nuclear pore and inhibits the movement of macromolecules into and out of the nucleus. The PRn poly-dipeptide binds to polymeric forms of the phenylalanine:glycine (FG) repeat domain, which is shared by several proteins of the nuclear pore complex, including those in the central channel. A method of chemical footprinting was used to characterize labile, cross-ß polymers formed from the FG domain of the Nup54 protein. Mutations within the footprinted region of Nup54 polymers blocked both polymerization and binding by the PRn poly-dipeptide. The aliphatic alcohol 1,6-hexanediol melted FG domain polymers in vitro and reversed PRn-mediated enhancement of the nuclear pore permeability barrier. These data suggest that toxicity of the PRn poly-dipeptide results in part from its ability to lock the FG repeats of nuclear pore proteins in the polymerized state. Our study offers a mechanistic interpretation of PRn poly-dipeptide toxicity in the context of a prominent form of ALS.

Influence of bilateral cochlear implants on vocal control.

Receiving a cochlear implant (CI) can improve fundamental frequency (F0) control for deaf individuals, resulting in increased vocal pitch control. However, it is unclear whether using bilateral CIs, which often result in mismatched pitch perception between ears, will counter this benefit. To investigate this, 23 bilateral CI users were asked to produce a sustained vocalization using one CI, the other CI, both CIs, or neither. Additionally, a set of eight normal hearing participants completed the sustained vocalization task as a control group. The results indicated that F0 control is worse with both CIs compared to using the ear that yields the lowest vocal variability. The results also indicated that there was a large range of F0 variability even for the relatively stable portion of the vocalization, spanning from 6 to 46 cents. These results suggest that bilateral CIs can detrimentally affect vocal control.

Late-stage nodular erythema elevatum diutinum mimicking sclerotic fibroma.

Erythema elevatum diutinum (EED) is a rare, cutaneous vasculitis of uncertain origin. EED can present clinically as chronic bilateral, symmetrical, periarticular papules, plaques and nodules. We report here an unusual case of EED presenting as multiple, densely fibrosing nodules on the feet of a 60-year-old human immunodeficiency virus positive woman. The initial evaluation of the patient was complicated by the strong histologic resemblance of multiple lesions to sclerotic fibroma, a cutaneous manifestation of Cowden disease. Our case highlights the important features that distinguish these 2 pathologic entities.

Extrahelical (CAG)/(CTG) triplet repeat elements support proliferating cell nuclear antigen loading and MutLα endonuclease activation.

MutLα endonuclease can be activated on covalently continuous DNA that contains a MutSα- or MutSß-recognizable lesion and a helix perturbation that supports proliferating cell nuclear antigen (PCNA) loading by replication factor C, providing a potential mechanism for triggering mismatch repair on nonreplicating DNA. Because mouse models for somatic expansion of disease-associated (CAG)n/(CTG)n triplet repeat sequences have implicated both MutSß and MutLα and have suggested that expansions can occur in the absence of replication, we have asked whether an extrahelical (CAG)n or (CTG)n element is sufficient to trigger MutLα activation. (CAG)n and (CTG)n extrusions in relaxed closed circular DNA do in fact support MutSß-, replication factor C-, and PCNA-dependent activation of MutLα endonuclease, which can incise either DNA strand. Extrahelical elements of two or three repeat units are the preferred substrates for MutLα activation, and extrusions of this size also serve as moderately effective sites for loading the PCNA clamp. Relaxed heteroduplex DNA containing a two or three-repeat unit extrusion also triggers MutSß- and MutLα-endonuclease-dependent mismatch repair in nuclear extracts of human cells. This reaction occurs without obvious strand bias at about 10% the rate of that observed with otherwise identical nicked heteroduplex DNA. These findings provide a mechanism for initiation of triplet repeat processing in nonreplicating DNA that is consistent with several features of the model of Gomes-Pereira et al. [Gomes-Pereira M, Fortune MT, Ingram L, McAbney JP, Monckton DG (2004) Hum Mol Genet 13(16):1815-1825]. They may also have implications for triplet repeat processing at a replication fork.

The Genotype and Phenotypes in Families (GPF) platform manages the large and complex data at SFARI.

The exploration of genotypic variants impacting phenotypes is a cornerstone in genetics research. The emergence of vast collections containing deeply genotyped and phenotyped families has made it possible to pursue the search for variants associated with complex diseases. However, managing these large-scale datasets requires specialized computational tools tailored to organize and analyze the extensive data. GPF (Genotypes and Phenotypes in Families) is an open-source platform ( https://github.com/iossifovlab/gpf ) that manages genotypes and phenotypes derived from collections of families. The GPF interface allows interactive exploration of genetic variants, enrichment analysis for de novo mutations, and phenotype/genotype association tools. In addition, GPF allows researchers to share their data securely with the broader scientific community. GPF is used to disseminate two large-scale family collection datasets (SSC, SPARK) for the study of autism funded by the SFARI foundation. However, GPF is versatile and can manage genotypic data from other small or large family collections. Our GPF-SFARI GPF instance ( https://gpf.sfari.org/ ) provides protected access to comprehensive genotypic and phenotypic data for the SSC and SPARK. In addition, GPF-SFARI provides public access to an extensive collection of de novo mutations identified in individuals with autism and related disorders and to gene-level statistics of the protected datasets characterizing the genes' roles in autism. Here, we highlight the primary features of GPF within the context of GPF-SFARI.

Mohs micrographic surgery for periocular skin cancer: a single-institution experience.

Periocular skin cancers require both effective and tissue-sparing treatment to minimize morbidity and preserve eyelid and lacrimal system function. We aim to define outcomes of periocular tumors treated with Mohs micrographic surgery (MMS) and factors associated with poor outcomes after surgery. This is a retrospective cohort study of all periocular tumors treated with MMS at an academic, large metropolitan-based referral center from January 1, 2013 to December 31, 2018. For 316 tumors from 307 patients, 75.3% of cases were basal cell carcinoma (BCC) (n = 238), 20.9% were squamous cell carcinoma (SCC) (n = 66), 2.5% were melanoma (n = 8), and 1.3% were primary adnexal carcinoma (n = 4). Over a mean follow-up of 47 months (range 12-108 months), local recurrence of two BCCs was observed. There were no recurrences for SCC, adnexal carcinoma, or melanoma. For BCC, previously treated tumors had higher risk for recurrence after MMS. AJCC 8 T stage was not associated with poor outcomes after MMS for periocular carcinoma or melanoma. Mohs micrographic surgery offers excellent cure rates for periocular cutaneous tumors. For basal cell carcinoma, previously treated lesions were associated with additional recurrence after MMS.