Selective Publication within Vascular Surgery: Characteristics of Discontinued and Unpublished Randomized Clinical Trials.

BACKGROUND: Discontinued and unpublished randomized clinical trials (RCTs) are common resulting in biased publication and loss of potential knowledge. The magnitude of selective publication within vascular surgery remains unknown. METHODS: RCT relevant to vascular surgery registered (01/01/2010-10/31/2019) on ClinicalTrials.gov were included. Trials ending normally with conclusion of participant treatment and examination were considered completed whereas discontinued trials stopped early. Publications were identified through automatically indexed PubMed citations on ClinicalTrials.gov or manually identified on PubMed or Google Scholar >30 months after the completion date, the date the final participant was examined, allowing time for publication. RESULTS: Of 108 RCT (n = 37, 837), 22.2% (24/108) were discontinued, including 16.7% (4/24) stopped prior to and 83.3% (20/24) after starting enrollment. Only 28.4% of estimated enrollment was achieved for all discontinued RCT. Nineteen (79.2%) investigators provided a reason for discontinuation, which most commonly included poor enrollment (45.8%), inadequate supplies or funding (12.5%), and trial design concerns (8.3%). Of the 20 trials terminated following enrollment, 20.0% (4/20) were published in peer-reviewed journals and 80.0% (16/20) failed to reach publication. Of the 77.8% trials completed, 75.0% (63/84) were published and 25.0% (21/84) remain unpublished. In a multivariate regression of completed trials, industry funding was significantly associated with decreased likelihood of peer-reviewed publication (OR = 0.18, (95% CI 0.05-0.71), P = 0.01). Of the discontinued and completed trials remaining unpublished, 62.5% and 61.9% failed to report results on ClinicalTrials.gov, respectively, encompassing a total of 4,788 enrollees without publicly available results. CONCLUSIONS: Nearly 25% of registered vascular RCT were discontinued. Of completed RCT, 25% remain unpublished with industry funding associated with decreased likelihood of publication. This study identifies opportunities to report all findings for completed and discontinued vascular surgery RCT, whether industry sponsored, or investigator initiated.

Deficits in integrative NMDA receptors caused by Grin1 disruption can be rescued in adulthood.

Glutamatergic NMDA receptors (NMDAR) are critical for cognitive function, and their reduced expression leads to intellectual disability. Since subpopulations of NMDARs exist in distinct subcellular environments, their functioning may be unevenly vulnerable to genetic disruption. Here, we investigate synaptic and extrasynaptic NMDARs on the major output neurons of the prefrontal cortex in mice deficient for the obligate NMDAR subunit encoded by Grin1 and wild-type littermates. With whole-cell recording in brain slices, we find that single, low-intensity stimuli elicit surprisingly-similar glutamatergic synaptic currents in both genotypes. By contrast, clear genotype differences emerge with manipulations that recruit extrasynaptic NMDARs, including stronger, repetitive, or pharmacological stimulation. These results reveal a disproportionate functional deficit of extrasynaptic NMDARs compared to their synaptic counterparts. To probe the repercussions of this deficit, we examine an NMDAR-dependent phenomenon considered a building block of cognitive integration, basal dendrite plateau potentials. Since we find this phenomenon is readily evoked in wild-type but not in Grin1-deficient mice, we ask whether plateau potentials can be restored by an adult intervention to increase Grin1 expression. This genetic manipulation, previously shown to restore cognitive performance in adulthood, successfully rescues electrically-evoked basal dendrite plateau potentials after a lifetime of NMDAR compromise. Taken together, our work demonstrates NMDAR subpopulations are not uniformly vulnerable to the genetic disruption of their obligate subunit. Furthermore, the window for functional rescue of the more-sensitive integrative NMDARs remains open into adulthood.

COVID-associated acute limb ischemia during the Delta surge and the effect of vaccines.

OBJECTIVE: Hypercoagulability is common in severe acute respiratory syndrome coronavirus 2 and has been associated with arterial thrombosis leading to acute limb ischemia (ALI). Our objective was to determine the outcomes of concurrent coronavirus disease 2019 (COVID-19) infection and ALI, particularly during the Delta variant surge and the impact of vaccination status. METHODS: A retrospective review was performed of patients treated at a single health care system between March 2020 and December 2021 for ALI and recent (<14 days) COVID-19 infection or who developed ALI during hospitalization for the same disease. Patients were grouped by year as well as by pre and post Delta variant emergence in 2021 based on the World Health Organization timeline (January to May vs June to December). Baseline demographics, imaging, interventions, and outcomes were evaluated. A control cohort of all patients with ALI requiring surgical intervention for a 2-year period prior to the pandemic was used for comparison. Primary outcomes were in-hospital mortality and amputation-free survival. Kaplan-Meier survival and Cox proportional hazards analysis were performed. RESULTS: Forty acutely ischemic limbs were identified in 36 patients with COVID-19, the majority during the Delta surge (52.8%) and after the wide availability of vaccines. The rate of COVID-19-associated ALI, although low overall, nearly doubled during the Delta surge (0.37% vs 0.20%; P = .09). Intervention (open or endovascular revascularization vs primary amputation) was performed on 31 limbs in 28 individuals, with the remaining eight treated with systemic anti-coagulation. Postoperative mortality was 48%, and overall mortality was 50%. Major amputation following revascularization was significantly higher with COVID-19 ALI (25% vs 3%; P = .006) compared with the pre-pandemic group. Thirty-day amputation-free survival was significantly lower (log-rank P < .001). COVID-19 infection (adjusted hazard ratio, 6.2; P < .001) and age (hazard ratio, 1.1; P = .006) were associated with 30-day amputation in multivariate analysis. Severity of COVID-19 infection, defined as vasopressor usage, was not associated with post-revascularization amputation. There was a higher incidence of re-thrombosis in the latter half of 2021 with the Delta surge, as reintervention for recurrent ischemia of the same limb was more common than our previous experience (21% vs 0%; P = .55). COVID-19-associated limb ischemia occurred almost exclusively in non-vaccinated patients (92%). CONCLUSIONS: ALI observed with Delta appears more resistant to standard therapy. Unvaccinated status correlated highly with ALI occurrence in the setting of COVID-19 infection. Information of limb loss as a COVID-19 complication among non-vaccinated patients may help to increase compliance.

Facial Nerve Repair: Bioengineering Approaches in Preclinical Models.

Injury to the facial nerve can occur after different etiologies and range from simple transection of the branches to varying degrees of segmental loss. Management depends on the extent of injury and options include primary repair for simple transections and using autografts, allografts, or conduits for larger gaps. Tissue engineering plays an important role to create artificial materials that are able to mimic the nerve itself without extra morbidity in the patients. The use of neurotrophic factors or stem cells inside the conduits or around the repair site is being increasingly studied to enhance neural recovery to a greater extent. Preclinical studies remain the hallmark for development of these novel approaches and translation into clinical practice. This review will focus on preclinical models of repair after facial nerve injury to help researchers establish an appropriate model to quantify recovery and analyze functional outcomes. Different bioengineered materials, including conduits and nerve grafts, will be discussed based on the experimental animals that were used and the defects introduced. Future directions to extend the applications of processed nerve allografts, bioengineered conduits, and cues inside the conduits to induce neural recovery after facial nerve injury will be highlighted. Impact statement Recovery after facial nerve injury is a complex process, which involves different management options such as primary repair or the use of nerve grafts or conduits. Various tissue-engineered approaches are increasingly studied on preclinical models with limited, but promising, translation to the clinical setting. Herein, preclinical models focusing on different recovery methods after facial nerve injury are comprehensively reviewed based on the experimental animals used. The review provides key insights into current developments and future directions on this highly relevant topic to help researchers further expand the field of tissue engineering and facial nerve recovery.

Consequences of NMDA receptor deficiency can be rescued in the adult brain.

N-methyl-D-aspartate receptors (NMDARs) are required to shape activity-dependent connections in the developing and adult brain. Impaired NMDAR signalling through genetic or environmental insults causes a constellation of neurodevelopmental disorders that manifest as intellectual disability, epilepsy, autism, or schizophrenia. It is not clear whether the developmental impacts of NMDAR dysfunction can be overcome by interventions in adulthood. This question is paramount for neurodevelopmental disorders arising from mutations that occur in the GRIN genes, which encode NMDAR subunits, and the broader set of mutations that disrupt NMDAR function. We developed a mouse model where a congenital loss-of-function allele of Grin1 can be restored to wild type by gene editing with Cre recombinase. Rescue of NMDARs in adult mice yields surprisingly robust improvements in cognitive functions, including those that are refractory to treatment with current medications. These results suggest that neurodevelopmental disorders arising from NMDAR deficiency can be effectively treated in adults.