Electromyometrial Imaging of Uterine Contractions in Pregnant Women.

During normal pregnancy, the uterine smooth muscle, the myometrium, begins to have weak, uncoordinated contractions at late gestation to help the cervix remodel. In labor, the myometrium has strong, coordinated contractions to deliver the fetus. Various methods have been developed to monitor uterine contraction patterns to predict labor onset. However, the current techniques have limited spatial coverage and specificity. We developed electromyometrial imaging (EMMI) to noninvasively map uterine electrical activity onto the three-dimensional uterine surface during contractions. The first step in EMMI is to use T1-weighted magnetic resonance imaging to acquire the subject-specific body-uterus geometry. Next, up to 192 pin-type electrodes placed on the body surface are used to collect electrical recordings from the myometrium. Finally, the EMMI data processing pipeline is performed to combine the body-uterus geometry with body surface electrical data to reconstruct and image uterine electrical activities on the uterine surface. EMMI can safely and noninvasively image, identify, and measure early activation regions and propagation patterns across the entire uterus in three dimensions.

Noninvasive electromyometrial imaging of human uterine maturation during term labor.

Electromyometrial imaging (EMMI) was recently developed to image the three-dimensional (3D) uterine electrical activation during contractions noninvasively and accurately in sheep. Herein we describe the development and application of a human EMMI system to image and evaluate 3D uterine electrical activation patterns at high spatial and temporal resolution during human term labor. We demonstrate the successful integration of the human EMMI system during subjects' clinical visits to generate noninvasively the uterine surface electrical potential maps, electrograms, and activation sequence through an inverse solution using up to 192 electrodes distributed around the abdomen surface. Quantitative indices, including the uterine activation curve, are developed and defined to characterize uterine surface contraction patterns. We thus show that the human EMMI system can provide detailed 3D images and quantification of uterine contractions as well as novel insights into the role of human uterine maturation during labor progression.

Estimated Prevalence and Clinical Manifestations of UBA1 Variants Associated With VEXAS Syndrome in a Clinical Population.

Importance: VEXAS (vacuoles, E1-ubiquitin-activating enzyme, X-linked, autoinflammatory, somatic) syndrome is a disease with rheumatologic and hematologic features caused by somatic variants in UBA1. Pathogenic variants are associated with a broad spectrum of clinical manifestations. Knowledge of prevalence, penetrance, and clinical characteristics of this disease have been limited by ascertainment biases based on known phenotypes. Objective: To determine the prevalence of pathogenic variants in UBA1 and associated clinical manifestations in an unselected population using a genomic ascertainment approach. Design, Setting, and Participants: This retrospective observational study evaluated UBA1 variants in exome data from 163 096 participants within the Geisinger MyCode Community Health Initiative. Clinical phenotypes were determined from Geisinger electronic health record data from January 1, 1996, to January 1, 2022. Exposures: Exome sequencing was performed. Main Outcomes and Measures: Outcome measures included prevalence of somatic UBA1 variation; presence of rheumatologic, hematologic, pulmonary, dermatologic, and other findings in individuals with somatic UBA1 variation on review of the electronic health record; review of laboratory data; bone marrow biopsy pathology analysis; and in vitro enzymatic assays. Results: In 163 096 participants (mean age, 52.8 years; 94% White; 61% women), 11 individuals harbored likely somatic variants at known pathogenic UBA1 positions, with 11 of 11 (100%) having clinical manifestations consistent with VEXAS syndrome (9 male, 2 female). A total of 5 of 11 individuals (45%) did not meet criteria for rheumatologic and/or hematologic diagnoses previously associated with VEXAS syndrome; however, all individuals had anemia (hemoglobin: mean, 7.8 g/dL; median, 7.5 g/dL), which was mostly macrocytic (10/11 [91%]) with concomitant thrombocytopenia (10/11 [91%]). Among the 11 patients identified, there was a pathogenic variant in 1 male participant prior to onset of VEXAS-related signs or symptoms and 2 female participants had disease with heterozygous variants. A previously unreported UBA1 variant (c.1861A>T; p.Ser621Cys) was found in a symptomatic patient, with in vitro data supporting a catalytic defect and pathogenicity. Together, disease-causing UBA1 variants were found in 1 in 13 591 unrelated individuals (95% CI, 1:7775-1:23 758), 1 in 4269 men older than 50 years (95% CI, 1:2319-1:7859), and 1 in 26 238 women older than 50 years (95% CI, 1:7196-1:147 669). Conclusions and Relevance: This study provides an estimate of the prevalence and a description of the clinical manifestations of UBA1 variants associated with VEXAS syndrome within a single regional health system in the US. Additional studies are needed in unselected and genetically diverse populations to better define general population prevalence and phenotypic spectrum.

A multidisciplinary Prematurity Research Cohort Study.

BACKGROUND: Worldwide, 10% of babies are born preterm, defined as a live birth before 37 weeks of gestation. Preterm birth is the leading cause of neonatal death, and survivors face lifelong risks of adverse outcomes. New approaches with large sample sizes are needed to identify strategies to predict and prevent preterm birth. The primary aims of the Washington University Prematurity Research Cohort Study were to conduct three prospective projects addressing possible causes of preterm birth and provide data and samples for future research. STUDY DESIGN: Pregnant patients were recruited into the cohort between January 2017 and January 2020. Consenting patients were enrolled into the study before 20 weeks' gestation and followed through delivery. Participants completed demographic and lifestyle surveys; provided maternal blood, placenta samples, and cord blood; and participated in up to three projects focused on underlying physiology of preterm birth: cervical imaging (Project 1), circadian rhythms (Project 2), and uterine magnetic resonance imaging and electromyometrial imaging (Project 3). RESULTS: A total of 1260 participants were enrolled and delivered during the study period. Of the participants, 706 (56%) were Black/African American, 494 (39%) were nulliparous, and 185 (15%) had a previous preterm birth. Of the 1260 participants, 1220 (97%) delivered a live infant. Of the 1220 with a live birth, 163 (14.1%) had preterm birth, of which 74 (6.1%) were spontaneous preterm birth. Of the 1220 participants with a live birth, 841 participated in cervical imaging, 1047 contributed data and/or samples on circadian rhythms, and 39 underwent uterine magnetic resonance imaging. Of the 39, 25 underwent electromyometrial imaging. CONCLUSION: We demonstrate feasibility of recruiting and retaining a diverse cohort in a complex prospective, longitudinal study throughout pregnancy. The extensive clinical, imaging, survey, and biologic data obtained will be used to explore cervical, uterine, and endocrine physiology of preterm birth and can be used to develop novel approaches to predict and prevent preterm birth.

RNA-Seq identifies genes whose proteins are upregulated during syncytia development in murine C2C12 myoblasts and human BeWo trophoblasts.

The fusion of villous cytotrophoblasts into the multinucleated syncytiotrophoblast is critical for the essential functions of the mammalian placenta. Using RNA-Seq gene expression, quantitative protein expression, and siRNA knockdown we identified genes and their cognate proteins which are similarly upregulated in two cellular models of mammalian syncytia development (human BeWo cytotrophoblast to syncytiotrophoblast and murine C2C12 myoblast to myotube). These include DYSF, PDE4DIP, SPIRE2, NDRG1, PLEC, GPR146, HSPB8, DHCR7, and HDAC5. These findings provide avenues for further understanding of the mechanisms underlying mammalian placental syncytiotrophoblast development.

Electromyometrial imaging dataset of electromyograms and isochrone maps under deformation/electrical noise contaminations.

The dataset presented in this paper is related to the recent work "Accuracy of electromyometrial imaging of uterine contractions in clinical environment" [1]. The dataset including body-uterus geometry obtained from magnetic resonance imaging (MRI), uterine electrograms and isochrone maps reconstructed using Electromyometrial imaging (EMMI) under various levels of deformations and electrical noise contamination in a translational sheep model are reported. The dataset make it possible for detailed evaluation and further improvement of EMMI. In addition, the researchers working on other types of electrophysiology imaging techniques, such as electrocardiographic imaging (ECGI), and Electrogastrography imaging (EGGI) could also adopt our method [1] and employ the dataset to evaluate and improve their imaging techniques.

Accuracy of electromyometrial imaging of uterine contractions in clinical environment.

Clinically, uterine contractions are monitored with tocodynamometers or intrauterine pressure catheters. In the research setting, electromyography (EMG), which detects electrical activity of the uterus from a few electrodes on the abdomen, is feasible, can provide more accurate data than these other methods, and may be useful for predicting preterm birth. However, EMG lacks sufficient spatial resolution and coverage to reveal where uterine contractions originate, how they propagate, and whether preterm contractions differ between women who do and do not progress to preterm delivery. To address those limitations, electromyometrial imaging (EMMI) was recently developed and validated to non-invasively assess three-dimensional (3D) electrical activation patterns on the entire uterine surface in pregnant sheep. EMMI uses magnetic resonance imaging to obtain subject-specific body-uterus geometry and collects uterine EMG data from up to 256 electrodes on the body surface. EMMI software then solves an ill-posed inverse computation to combine the two datasets and generate maps of electrical activity on the entire 3D uterine surface. Here, we assessed the feasibility to clinically translate EMMI by evaluating EMMI's accuracy under the unavoidable geometrical alterations and electrical noise contamination in a clinical environment. We developed a hybrid experimental-simulation platform to model the effects of fetal kicks, contractions, fetal/maternal movements, and noise contamination caused by maternal respiration and environmental electrical activity. Our data indicate that EMMI can accurately image uterine electrical activity in the presence of geometrical deformations and electrical noise, suggesting that EMMI can be reliably translated to non-invasively image 3D uterine electrical activation in pregnant women.

Noninvasive high-resolution electromyometrial imaging of uterine contractions in a translational sheep model.

In current clinical practice, uterine contractions are monitored via a tocodynamometer or an intrauterine pressure catheter, both of which provide crude information about contractions. Although electrohysterography/electromyography can measure uterine electrical activity, this method lacks spatial specificity and thus cannot accurately measure the exact location of electrical initiation and location-specific propagation patterns of uterine contractions. To comprehensively evaluate three-dimensional uterine electrical activation patterns, we describe here the development of electromyometrial imaging (EMMI) to display the three-dimensional uterine contractions at high spatial and temporal resolution. EMMI combines detailed body surface electrical recording with body-uterus geometry derived from magnetic resonance images. We used a sheep model to show that EMMI can reconstruct uterine electrical activation patterns from electrodes placed on the abdomen. These patterns closely match those measured with electrodes placed directly on the uterine surface. In addition, modeling experiments showed that EMMI reconstructions are minimally affected by noise and geometrical deformation. Last, we show that EMMI can be used to noninvasively measure uterine contractions in sheep in the same setup as would be used in humans. Our results indicate that EMMI can noninvasively, safely, accurately, robustly, and feasibly image three-dimensional uterine electrical activation during contractions in sheep and suggest that similar results might be obtained in clinical setting.

RNA-Seq identifies genes whose proteins are transformative in the differentiation of cytotrophoblast to syncytiotrophoblast, in human primary villous and BeWo trophoblasts.

The fusion of villous cytotrophoblasts into the multinucleated syncytiotrophoblast is critical for the essential functions of the mammalian placenta. Using RNA-Seq gene expression and quantitative protein expression, we identified genes and their cognate proteins which are coordinately up- or down-regulated in two cellular models of cytotrophoblast to syncytiotrophoblast development, human primary villous and human BeWo cytotrophoblasts. These include hCGß, TREML2, PAM, CRIP2, INHA, FLRG, SERPINF1, C17orf96, KRT17 and SAA1. These findings provide avenues for further understanding the mechanisms underlying mammalian placental synctiotrophoblast development.

RNF4-Dependent Oncogene Activation by Protein Stabilization.

Ubiquitylation regulates signaling pathways critical for cancer development and, in many cases, targets proteins for degradation. Here, we report that ubiquitylation by RNF4 stabilizes otherwise short-lived oncogenic transcription factors, including ß-catenin, Myc, c-Jun, and the Notch intracellular-domain (N-ICD) protein. RNF4 enhances the transcriptional activity of these factors, as well as Wnt- and Notch-dependent gene expression. While RNF4 is a SUMO-targeted ubiquitin ligase, protein stabilization requires the substrate's phosphorylation, rather than SUMOylation, and binding to RNF4's arginine-rich motif domain. Stabilization also involves generation of unusual polyubiquitin chains and docking of RNF4 to chromatin. Biologically, RNF4 enhances the tumor phenotype and is essential for cancer cell survival. High levels of RNF4 mRNA correlate with poor survival of a subgroup of breast cancer patients, and RNF4 protein levels are elevated in 30% of human colon adenocarcinomas. Thus, RNF4-dependent ubiquitylation translates transient phosphorylation signal(s) into long-term protein stabilization, resulting in enhanced oncoprotein activation.

Isoform-specific SCF(Fbw7) ubiquitination mediates differential regulation of PGC-1α.

The E3 ubiquitin ligase and tumor suppressor SCF(Fbw7) exists as three isoforms that govern the degradation of a host of critical cell regulators, including c-Myc, cyclin E, and PGC-1α. Peroxisome proliferator activated receptor-gamma coactivator 1α (PGC-1α) is a transcriptional coactivator with broad effects on cellular energy metabolism. Cellular PGC-1α levels are tightly controlled in a dynamic state by the balance of synthesis and rapid degradation via the ubiquitin-proteasome system. Isoform-specific functions of SCF(Fbw7) are yet to be determined. Here, we show that the E3 ubiquitin ligase, SCF(Fbw7), regulates cellular PGC-1α levels via two independent, isoform-specific, mechanisms. The cytoplasmic isoform (SCF(Fbw7ß)) reduces cellular PGC-1α levels via accelerated ubiquitin-proteasome degradation. In contrast, the nuclear isoform (SCF(Fbw7α)) increases cellular PGC-1α levels and protein stability via inhibition of ubiquitin-proteasomal degradation. When nuclear Fbw7α proteins are redirected to the cytoplasm, cellular PGC-1α protein levels are reduced through accelerated ubiquitin-proteasomal degradation. We find that SCF(Fbw7ß) catalyzes high molecular weight PGC-1α-ubiquitin conjugation, whereas SCF(Fbw7α) produces low molecular weight PGC-1α-ubiquitin conjugates that are not effective degradation signals. Thus, selective ubiquitination by specific Fbw7 isoforms represents a novel mechanism that tightly regulates cellular PGC-1α levels. Fbw7 isoforms mediate degradation of a host of regulatory proteins. The E3 ubiquitin ligase, Fbw7, mediates PGC-1α levels via selective isoform-specific ubiquitination. Fbw7ß reduces cellular PGC-1α via ubiquitin-mediated degradation, whereas Fbw7α increases cellular PGC-1α via ubiquitin-mediated stabilization.

Commentary: physician-scientist attrition: stemming the tide through national networks for training and development.

Future advances in medicine depend on a reliable pipeline of physician-scientists. However, the changing demographics of physician-scientists, including the advanced age of new MD investigators, and attrition along the physician-scientist developmental pathway are cause for concern. Recently developed National Institutes of Health-funded national networks for physician-scientist training and development-such as the Advanced Research Institute in Geriatric Mental Health and the Pediatric Scientist Development Program-offer valuable approaches to supporting and retaining these trainees.

The Future of Children's Health in the Genomic Era.

The effects of genomic medicine on child health promise to be profound. Medical applications will eventually include characterizing patients' genomes to detect predictive mutations for pre-symptomatic counseling where treatment exists; to search for causes of diseases of unknown etiology, and to detect carriers for prenatal counseling; to define cancer and other disease-based genomes to design individualized therapy; and to understand our microbiomes to modify these in health and disease. Rapid advances in technology and bioinformatics have reduced the cost and the time and increased the accuracy necessary to sequence whole genomes or whole exomes. However, complete understanding of disease will also require correlation of genomic information with high-quality phenotypic data. In addition, several critical ethical, psycho-social, and public policy issues will require clarity in the coming years. Ultimately these advances will improve the effectiveness of health care for children and for society.

Ubiquitin proteasome-dependent degradation of the transcriptional coactivator PGC-1{alpha} via the N-terminal pathway.

PGC-1α is a potent, inducible transcriptional coactivator that exerts control on mitochondrial biogenesis and multiple cellular energy metabolic pathways. PGC-1α levels are controlled in a highly dynamic manner reflecting regulation at both transcriptional and post-transcriptional levels. Here, we demonstrate that PGC-1α is rapidly degraded in the nucleus (t(½ 0.3 h) via the ubiquitin proteasome system. An N-terminal deletion mutant of 182 residues, PGC182, as well as a lysine-less mutant form, are nuclear and rapidly degraded (t(½) 0.5 h), consistent with degradation via the N terminus-dependent ubiquitin subpathway. Both PGC-1α and PGC182 degradation rates are increased in cells under low serum conditions. However, a naturally occurring N-terminal splice variant of 270 residues, NT-PGC-1α is cytoplasmic and stable (t(½>7 h), providing additional evidence that PGC-1α is degraded in the nucleus. These results strongly suggest that the nuclear N terminus-dependent ubiquitin proteasome pathway governs PGC-1α cellular degradation. In contrast, the cellular localization of NT-PCG-1α results in a longer-half-life and possible distinct temporal and potentially biological actions.

Low-density lipoprotein receptor-related protein 1 promotes cancer cell migration and invasion by inducing the expression of matrix metalloproteinases 2 and 9.

The low-density lipoprotein receptor-related protein 1 (LRP1) is a multifunctional endocytic receptor involved in the metabolism of various extracellular ligands, including proteinases, that play critical roles in tumor invasion. Although several studies have shown an increased expression of LRP1 in cancer cells, its function in tumor development and progression remains largely unclear. Here, we reveal a novel mechanism by which LRP1 induces the expression of matrix metalloproteinase 2 (MMP2) and MMP9 and thereby promotes the migration and invasion of human glioblastoma U87 cells. Knockdown of LRP1 expression greatly decreased U87 cell migration and invasion, which was rescued by the forced expression of a functional LRP1 minireceptor. Inhibition of ligand binding to LRP1 by a specific antagonist, receptor-associated protein, also led to reduced cancer cell migration and invasion. Because MMPs play critical roles in cancer cell migration and invasion, we examined the expression of several MMPs and found that the expression of functional MMP2 and MMP9 was selectively decreased in LRP1 knockdown cells. More importantly, decreased cell migration and invasion of LRP1 knockdown cells were completely rescued by exogenous expression of MMP2 or MMP9, suggesting that these MMPs are likely downstream targets of LRP1-mediated signaling. We further show that the level of phosphorylated extracellular signal-regulated kinase (ERK) was significantly decreased in LRP1-silenced cells, suggesting that ERK is a potential mediator of LRP1-regulated MMP2 and MMP9 expression in U87 cells. Together, our data strongly suggest that LRP1 promotes glioblastoma cell migration and invasion by regulating the expression and function of MMP2 and MMP9 perhaps via an ERK-dependent signaling pathway.

Targeting proteins for destruction by the ubiquitin system: implications for human pathobiology.

Cellular proteins are in a dynamic state maintained by synthesis and degradation. The ubiquitin proteolytic pathway is responsible for the degradation of the bulk of cellular proteins including short-lived, regulatory, and misfolded/denatured proteins. Ubiquitin-mediated proteolysis involves covalent attachment of multiple ubiquitin molecules to the protein substrate and degradation of the targeted protein by the 26S proteasome. Recent understanding of the molecular mechanisms involved provides a framework to understand a wide variety of human pathophysiological states as well as therapeutic interventions. This review focuses on the response to hypoxia, inflammatory diseases, neurodegenerative diseases, and muscle-wasting disorders, as well as human papillomaviruses, cervical cancer and other malignancies.