Intraoperative transabdominal MEPs: four case reports.

Four recent cases utilizing transabdominal motor-evoked potentials (TaMEPs) are presented as illustrative of the monitoring technique during lumbosacral fusion, sciatic nerve tumor resection, cauda equina tumor resection, and lumbar decompression. Case 1: In a high-grade lumbosacral spondylolisthesis revision fusion, both transcranial motor-evoked potentials (TcMEPs) and TaMEPs detected a transient focal loss of left tibialis anterior response in conjunction with L5 nerve root decompression. Case 2: In a sciatic nerve tumor resection, TcMEPs responses were lost but TaMEPs remained unchanged, the patient was neurologically intact postoperatively. Case 3: TaMEPs were acquired during an L1-L3 intradural extramedullary cauda equina tumor resection utilizing a unique TaMEP stimulation electrode. Case 4: TaMEPs were successfully acquired with little anesthetic fade utilizing an anesthetic regimen of 1.1 MAC Sevoflurane during a lumbar decompression. While the first two cases present TaMEPs and TcMEPs side-by-side, demonstrating TaMEPs correlating to TcMEPs (Case 1) or a more accurate reflection of patient outcome (Case 2), no inference regarding the accuracy of TaMEPs to monitor nerve elements during cauda equina surgery (Cases 3) or the lumbar decompression presented in Case 4 should be made as these are demonstrations of technique, not utility.

A History of Cerebrovascular Disease Is Independently Associated with Increased Morbidity and Mortality in Patients with COVID-19: A Cohort Study of 369,563 COVID-19 Cases in the USA.

OBJECTIVES: We set out to evaluate the risk for severe coronavirus disease 2019 (COVID-19) infection and subsequent cerebrovascular disease (CVD) in the population with a prior diagnosis of CVD within the past 10 years. METHODS: We utilized the TriNetX Analytics Network to query 369,563 CO-VID-19 cases up to December 30, 2020. We created 8 cohorts of patients with COVID-19 diagnosis based on a previous diagnosis of CVD. We measured the odds ratios, relative risks, risk differences for hospitalizations, ICU/critical care services, intubation, mortality, and CVD recurrence within 90 days of COVID-19 diagnosis, compared to a propensity-matched cohort with no prior history of CVD within 90 days of COVID-19 diagnosis. RESULTS: 369,563 patients had a confirmed diagnosis of COVID-19 with a subset of 22,497 (6.09%) patients with a prior diagnosis of CVD within 10 years. All cohorts with a CVD diagnosis had an increased risk of hospitalization, critical care services, and mortality within 90 days of COVID-19 diagnosis. Additionally, the data demonstrate that any history of CVD is associated with significantly increased odds of subsequent CVD post-COVID-19 compared to a matched control. CONCLUSIONS: CVD, a known complication of CO-VID-19, is more frequent in patients with a prior history of CVD. Patients with any previous diagnosis of CVD are at higher risks of morbidity and mortality from COVID-19 infection. In patients admitted to the ED due to COVID-19 symptoms, these risk factors should be promptly identified as delayed or missed risk stratification and could lead to an ineffective and untimely diagnosis of subsequent CVD, which would lead to protracted hospitalization and poor prognosis.

Human Pluripotent Stem Cell-Derived Multipotent Vascular Progenitors of the Mesothelium Lineage Have Utility in Tissue Engineering and Repair.

In this report we describe a human pluripotent stem cell-derived vascular progenitor (MesoT) cell of the mesothelium lineage. MesoT cells are multipotent and generate smooth muscle cells, endothelial cells, and pericytes and self-assemble into vessel-like networks in vitro. MesoT cells transplanted into mechanically damaged neonatal mouse heart migrate into the injured tissue and contribute to nascent coronary vessels in the repair zone. When seeded onto decellularized vascular scaffolds, MesoT cells differentiate into the major vascular lineages and self-assemble into vasculature capable of supporting peripheral blood flow following transplantation. These findings demonstrate in vivo functionality and the potential utility of MesoT cells in vascular engineering applications.

Vein of Galen Malformation Thrombosis by Single-Stage, 2-Coil Embolization.

Advances in endovascular embolization have improved morbidity and mortality among patients with vein of Galen malformations (VoGMs). The patient presented at 3 months of age with increased head circumference and a bruit over his anterior fontanelle. Diagnostic cerebral angiography confirmed the presence of a large mural-type VoGM. The decision was made to undergo a staged arterial embolization at 4 years of age after developing worsening right-sided hemiparesis. An attempt was made to occlude the posterior choroidal feeding vessel with a large 25 mm × 50 cm coil, followed by a 6 mm × 20 cm coil; however, the high flow of the lesion displaced both coils into the wall of the aneurysmal venous sac. Interval magnetic resonance imaging and angiography revealed partial occlusion of the VoGM at 7 months and complete thrombosis at 24 months post procedure, precluding a need for additional coiling. This case illustrates that a minimal change in intramural flow dynamics of VoGMs could lead to progressive thrombosis.

Nuclear structure and chromosome segregation in Drosophila male meiosis depend on the ubiquitin ligase dTopors.

In many organisms, homolog pairing and synapsis at meiotic prophase depend on interactions between chromosomes and the nuclear membrane. Male Drosophila lack synapsis, but nonetheless, their chromosomes closely associate with the nuclear periphery at prophase I. To explore the functional significance of this association, we characterize mutations in nuclear blebber (nbl), a gene required for both spermatocyte nuclear shape and meiotic chromosome transmission. We demonstrate that nbl corresponds to dtopors, the Drosophila homolog of the mammalian dual ubiquitin/small ubiquitin-related modifier (SUMO) ligase Topors. We show that mutations in dtopors cause abnormalities in lamin localizations, centriole separation, and prophase I chromatin condensation and also cause anaphase I bridges that likely result from unresolved homolog connections. Bridge formation does not require mod(mdg4) in meiosis, suggesting that bridges do not result from misregulation of the male homolog conjunction complex. At the ultrastructural level, we observe disruption of nuclear shape, an uneven perinuclear space, and excess membranous structures. We show that dTopors localizes to the nuclear lamina at prophase, and also transiently to intranuclear foci. As a role of dtopors at gypsy insulator has been reported, we also asked whether these new alleles affected expression of the gypsy-induced mutation ct(6) and found that it was unaltered in dtopors homozygotes. Our results indicate that dTopors is required for germline nuclear structure and meiotic chromosome segregation, but in contrast, is not necessary for gypsy insulator function. We suggest that dtopors plays a structural role in spermatocyte lamina that is critical for multiple aspects of meiotic chromosome transmission.