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BACKGROUND: Advancements in arterial stenting technology have challenged prior notions favoring medical management for intracranial atherosclerotic disease (ICAD). Where previous conclusions were drawn from bare metal stent (BMS) technology, recent studies suggest drug-eluting stents (DES) are favorable due to their anti-proliferative effect, which reduces vascular remodeling. METHODS: We conducted a systematic review and meta-analysis of the literature prior to August 2023 reviewing all reports of ICAD treated with DES. Our target outcomes were incidence of any stroke, transient ischemic attack (TIA), or death within 30 days (postprocedural complications), ischemic stroke in the territory of the qualifying artery beyond 30 days (long-term complications), radiographically detected in-stent restenosis rate (ISR), and symptomatic ISR during follow-up. A subgroup analysis further stratified preprocedural mean stenosis above and below 70% into severe and moderate cohorts, respectively. RESULTS: PubMed, Web of Science, Cochrane and EMBASE query identified 527 candidate articles, from which 14 studies met inclusion criteria for a total of 607 patients and 640 ICAD lesions. Incidence of postprocedural complications was 7.3% (95% CI 3.9-11.7%) with subgroup analysis demonstrating significantly higher incidence in the severely stenotic group [9.0% (95% CI 4.7-14.5%)] than the moderately stenotic group [3.0% (95% CI 0.7-6.8%)]. Long-term complications were 1.2% (95% CI 0.4-2.3%). Radiographic ISR was 3.5% (95% CI 1.4-6.3%) and symptomatic ISR was 0.3% (95% CI 0.0-1.5%). CONCLUSIONS: Our systematic review and meta-analysis suggest that DES can effectively reduce the risk of ISR and may be a viable treatment modality to reduce long-term complications in refractory ICAD patients.

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BACKGROUND: Doxorubicin, an anthracycline chemotherapeutic known to incur heart damage, decreases heart function in up to 11% of patients. Recent investigations have implicated the Wnt signaling cascade as a key modulator of cardiac tissue repair after myocardial infarction. Wnt upregulation in murine models resulted in stimulation of angiogenesis and suppression of fibrosis after ischemic insult. However, the molecular mechanisms of Wnt in mitigating doxorubicin-induced cardiac insult require further investigation. Identifying cardioprotective mechanisms of Wnt is imperative to reducing debilitating cardiovascular adverse events in oncologic patients undergoing treatment. METHODS: Exposing human cardiomyocyte AC16 cells to varying concentrations of Wnt10b and DOX, we observed key metrics of cell viability. To assess the viability and apoptotic rates, we utilized MTT and TUNEL assays. We quantified cell and mitochondrial membrane stability via LDH release and JC-1 staining. To investigate how Wnt10b mitigates doxorubicin-induced apoptosis, we introduced pharmacologic inhibitors of key enzymes involved in apoptosis: FR180204 and SB203580, ERK1/2 and p38 inhibitors. Further, we quantified apoptotic executor enzymes, caspase 3/7, via immunofluorescence. RESULTS: AC16 cells exposed solely to doxorubicin were shrunken with distorted morphology. Cardioprotective effects of Wnt10b were demonstrated via a reduction in apoptosis, from 70.1% to 50.1%. LDH release was also reduced between doxorubicin and combination groups from 2.27-fold to 1.56-fold relative to the healthy AC16 control group. Mitochondrial membrane stability was increased from 0.67-fold in the doxorubicin group to 5.73 in co-treated groups relative to control. Apoptotic protein expression was stifled by Wnt10b, with caspase3/7 expression reduced from 2.4- to 1.3-fold, and both a 20% decrease in p38 and 40% increase in ERK1/2 activity. CONCLUSION: Our data with the AC16 cell model demonstrates that Wnt10b provides defense mechanisms against doxorubicin-induced cardiotoxicity and apoptosis. Further, we explain a mechanism of this beneficial effect involving the mitochondria through simultaneous suppression of pro-apoptotic p38 and anti-apoptotic ERK1/2 activities.

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INTRODUCTION: First line treatment for cerebral venous thrombosis (CVT) is systemic anticoagulation. In cases with symptoms of elevated ICP, endovascular thrombectomy (EVT) is pursued. We describe two cases in which dual stent-retrievers were used for EVT. OBJECTIVES: The use of dual stent-retrievers has been described in arterial stroke when clot is present in the M1 artery and both M2 branches as a rescue therapy after 1 stent-retriever failed to remove the clot. We applied this same thinking to our EVT patients. METHODS: A 17-year-old female with imaging demonstrating occlusion of the superior sagittal sinus (SSS), dominant right transverse sinus (TS), right sigmoid sinus (SS), and upper right internal jugular vein (IJV). A 20-year-old female with a magnetic resonance venography (MRV) noting CVT in the dominant lateral left TS, SS, and upper left IJV. RESULTS: Both were taken for EVT due to severity of symptoms. Two 6 × 40 mm stent-retrievers were deployed into the CVT and then remove with continuous aspiration with significant recanalization. CONCLUSIONS: The average diameter of the dural sinuses is 8 mm compared to the average size of the middle cerebral artery 3-4 mm. The largest available SR in the United States is 6 mm, and the largest outer diameter of available aspiration catheters is 2-3 mm. Due to the larger size of the dural sinuses, using two SRs can result in more efficient recanalization and less radiation.

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INTRODUCTION: Programs that offer early exposure to surgery for medical students foster interest in and positive perceptions of surgery. The COVID-19 pandemic led to suspension of these activities at our institution, the University of Kansas School of Medicine. In response to the lack of virtual alternatives, a pilot virtual surgery enrichment program was implemented for first-year students in place of in-person surgical exposure. The aim of this study was to compare the efficacy of in-person and virtual-based surgical education programs to expose preclinical medical students about the surgical realm of medicine. METHODS: First-year medical students participated in either a virtual (Group A) or in-person (Group B) week-long surgical enrichment program. Group assignments were dictated by COVID restrictions on each of our three medical school campuses: Salina, Wichita, and Kansas City. Pre- and post-surveys with a 14-question multiple-choice assessment of surgical knowledge were distributed to participants. Paired Wilcoxon Signed Rank tests and Mann-Whitney-U tests were used for statistical analysis. RESULTS: There were 14 participants in Group A and 7 participants in Group B. Both groups improved significantly from pre- to post-assessment score. (Group A, p = 0.01; Group B, p = 0.04). There was no difference between groups in the magnitude of score improvement from pre- to post-assessment (p = 0.59). CONCLUSIONS: This pilot program demonstrated that virtual platforms can be a method to provide meaningful clinical experiences in surgery to preclinical medical students restricted from clinical activities. Further development of mentorship in virtual surgical programs and assessment of subjective experience is needed.

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BACKGROUND: There has not been any effective prophylaxis for delayed cerebral ischemia delayed cerebral ischemia (DCI) since the introduction of nimodipine. Platelet inhibition may reduce the risk by preventing the formation of microthrombi. Tirofiban has been used as a single monotherapy bridge given its safety profile and controlled platelet inhibition. OBJECTIVE: To assess the risk of DCI in aneurysmal subarachnoid hemorrhages (aSAH) patients treated with the tirofiban protocol. METHODS: aSAH patients between December 2010 and March 2019 who were treated with stent assisted coiling or flow-diverting device were started on a continuous tirofiban infusion protocol and were compared with patients who underwent coil embolization without antiplatelet therapy. Safety analysis was performed to assess DCI, hemorrhagic, and ischemic events. RESULTS: A total of 21 patients were included in the tirofiban series and 81 in the control group. There was no statistical difference in age, gender, Hunt-Hess grade, and Fisher scale between the 2 groups except for a higher Fisher grade II in the tirofiban group. Multivariate analysis revealed tirofiban to reduce the risk of vasospasm by 72 percent (OR .28, P = .03), without affecting the risk of hemorrhagic complications (OR = 0.50, P = .26). Tirofiban reduced the risk of symptomatic stroke endovascular procedure but it did not reach significance (P = .06). DCI, older age, and postprocedural symptomatic stroke were significant predictors of mortality. Tirofiban reduced the mortality risk, but this association was not statistically significant. CONCLUSION: The tirofiban protocol in aSAH patients reduces the risk of DCI without conferring additional risks. This supports previous findings were antiplatelet therapy reduced DCI in human and animal models.

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BACKGROUND: MR-quantitative susceptibility mapping (QSM) can identify microbleeds (MBs) in intracranial aneurysm (IA) wall associated with sentinel headache (SH) preceding subarachnoid hemorrhage. However, its use is limited, due to associated skull base bonny and air artifact. MR-vessel wall imaging (VWI) is not limited by such artifact and therefore could be an alternative to QSM. The purpose of this study was to investigate the correlation between QSM and VWI in detecting MBs and to help develop a diagnostic strategy for SH. METHODS: We performed a prospective study of subjects with one or more unruptured IAs in our hospital. All subjects underwent evaluation using 3T-MRI for MR angiography (MRA), QSM, and pre- and post-contrast VWI of the IAs. Presence/absence of MBs detected by QSM was correlated with aneurysm wall enhancement (AWE) on VWI. RESULTS: A total of 40 subjects harboring 51 unruptured IAs were enrolled in the study. MBs evident on the QSM sequence was detected in 12 (23.5%) IAs of 11 subjects. All these subjects had a history of severe headache suggestive of SH. AWE was detected in 22 (43.1%) IAs. Using positive QSM as a surrogate for MBs, the sensitivity, specificity, positive predictive value, and negative predictive value of AWE on VWI for detecting MBs were 91.7%, 71.8%, 50%, and 96.6%, respectively. CONCLUSIONS: Positive QSM findings strongly suggested the presence of MBs with SH, whereas, the lack of AWE on VWI can rule it out with a probability of 96.6%. If proven in a larger cohort, combining QSM and VWI could be an adjunctive tool to help diagnose SH, especially in cases with negative or non-diagnostic CT and lumbar puncture.

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The structure of cerium(IV) bis-(phosphite), Ce(HPO3)2, has been solved by single-crystal X-ray diffraction and has trigonal (P-3m1) symmetry. The cerium(IV) cation exhibits site symmetry -3m. and is octa-hedrally coordinated by O atoms of the phosphite ligands (point group symmetry 3m.). The highly symmetrical compound has a layered structure parallel to the ab plane, and is closely related to zirconium(IV) bis-(phosphite) solved via powder X-ray diffraction with trigonal (P-3 symmetry. Structural details of the two compounds are comparatively discussed.