Publications by authors named "Michael S Kim"

Background: Total talus replacement (TTR) implants are designed to replace the diseased talar anatomy, reduce pain, maintain ankle range of motion, and restore ankle function after conservative treatments have failed. Currently TTR implants are produced by 3D printing a patient-specific implant designed from the patient's preoperative anatomy. TTR surgery using patient-specific implants is a relatively new technique that remains understudied in the literature.

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This is a response to the letter to the editor from Dr. Ali et al. from Aga Khan University, Karachi, Pakistan.

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Hypothesis: Clinical studies are often at risk of spin, a form of bias where beneficial claims are overstated while negative findings are minimized or dismissed. Spin is often more problematic in abstracts given their brevity and can result in the misrepresentation of a study's actual findings. The goal of this study is to aggregate primary and secondary studies reporting the clinical outcomes of the use of subacromial balloon spacers in the treatment of massive irreparable rotator cuff tears to identify the incidence of spin and find any significant association with study design parameters.

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Background: Delays in starting postoperative radiotherapy (PORT) have been established as negative predictors for clinical outcomes in head and neck squamous cell carcinomas (HNSCC). Our study aimed to examine the effect of delays during PORT, and the impact of national holidays in Canada, a publicly funded system, on oncologic outcomes such as Overall Survival (OS) and Local Recurrence (LR).

Methods: The provincial cancer registry was queried to obtain demographic, pathologic, and outcomes data from cancer patients treated for all squamous cell carcinomas of the head and neck region treated between January 1, 2007 and November 30, 2019.

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Purpose: Current decision-making in multilevel cervical fusion weighs the potential to protect adjacent levels and reduce reoperation risk by crossing the cervicothoracic junction (C7/T1) against increased operative time and risk of complication. Careful planning is required, and the planned distal and adjacent levels should be assessed for degenerative disc disease (DDD). This study assessed whether DDD at the cervicothoracic junction was associated with DDD, disc height, translational motion, or angular variation in the adjacent superior (C6/C7) or inferior (T1/T2) levels.

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Background: The timing of events in the management of osteosarcoma may be critical for patient survivorship; however, the prognostic value of factors such as onset of symptoms or initiation of therapy in these patients has not been studied. This study sought to review the literature reporting treatment of osteosarcoma to determine the utility of event timing as a prognostic indicator. Due to significant heterogeneity in the literature, this study was conducted as a scoping review to assess the current state of the literature, identify strengths and weaknesses in current reporting practices, and to propose avenues for future improvement.

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Background: Small, preliminary studies and the systematic reviews on superior capsular reconstruction (SCR) that collate data are at increased risk spin. This study's primary objective was to identify, describe, and account for the incidence of spin in systematic reviews of SCR. This study's secondary objective was to characterize the studies in which spin was identified to determine whether identifiable patterns of characteristics exist among studies with spin.

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Management of locoregionally advanced head and neck cancers (HNCs) remains a challenge. Some groups have attempted to use stereotactic radiotherapy (SBRT) to deliver "boost" treatment following conventional radiotherapy to improve local control (LC) and overall survival (OS), while aiming for acceptable toxicities. Medline, EMBASE, and Cochrane Library databases were queried for SBRT as curative-intent planned boost in HNC after conventional radiotherapy.

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Purpose: Stereotactic body radiation therapy (SBRT) for de novo (previously untreated) head and neck cancers (HNCs) is increasingly being used in medically unfit patients. A systematic review of SBRT was conducted for previously untreated HNCs.

Methods And Materials: Medline (PubMed), excerpta medica database, and Cochrane Library databases were queried from inception until July 2020.

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Leucine Zipper EF-hand containing transmembrane protein-1 (LETM1) is an inner mitochondrial membrane protein that mediates mitochondrial calcium (Ca )/proton exchange. The matrix residing carboxyl (C)-terminal domain contains a sequence identifiable EF-hand motif (EF1) that is highly conserved among orthologues. Deletion of EF1 abrogates LETM1 mediated mitochondrial Ca flux, highlighting the requirement of EF1 for LETM1 function.

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Determination of the coplanar view is a critical component of transcatheter aortic valve replacement (TAVR). The safety and accuracy of a novel reduced angular range C-arm computed tomography (CACT) approach coupled with a fully automated 3D analysis tool package to predict the coplanar view in TAVR was evaluated. Fifty-seven patients with severe symptomatic aortic stenosis deemed prohibitive-risk for surgery and who underwent TAVR were enrolled.

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Folylpolyglutamate synthase (FPGS) plays a critical role in intracellular folate homeostasis. FPGS-induced polyglutamylated folates are better substrates for several enzymes involved in the generation of S-adenosylmethionine, the primary methyl group donor, and hence FPGS modulation may affect DNA methylation. DNA methylation is an important epigenetic determinant in gene expression and aberrant DNA methylation is mechanistically linked cancer development.

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The American Association for the Study of Liver Diseases practice guidelines list severe cardiac disease as a contraindication to liver transplantation. Transcatheter aortic valve replacement has been shown to decrease all-cause mortality in patients with severe aortic stenosis who are not considered candidates for surgical aortic valve replacement. We report our experience of liver transplantation in a patient with severe aortic stenosis and moderate aortic insufficiency who underwent transcatheter aortic valve replacement with Child-Pugh Class C disease at a Model For End-Stage Liver Disease score of 29.

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Objectives: A novel radiation dose reduction technology was evaluated in a cardiac catheterization laboratory during routine clinical care to determine if it could reduce radiation dose to patients undergoing coronary angiography and percutaneous coronary intervention. These results were compared to patients undergoing similar procedures in a cardiac catheterization laboratory without this technology.

Background: There is a safety priority in clinical care to reduce X-ray radiation dose to patients in order to lower the risk of deterministic and stochastic effects.

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The emergence of transcatheter valve technology over the last decade has made significant impact on the treatment of patients with valvular heart disease. There has been increasing experience with both native and valve-in-valve indications with promising results. We present the case of a young woman with congenital heart disease who underwent the Ross procedure for bicuspid aortic valve endocarditis with subsequent reoperation and surgical aortic valve replacement for neo-aortic root dilation who experienced worsening symptoms related to both pulmonary and aortic valve dysfunction.

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γ-Glutamyl hydrolase (GGH) plays an important role in folate homeostasis by catalyzing hydrolysis of polyglutamylated folate into monoglutamates. Polyglutamylated folates are better substrates for several enzymes involved in the generation of S-adenosylmethionine, the primary methyl group donor, and hence, GGH modulation may affect DNA methylation. DNA methylation is an important epigenetic determinant in gene expression, in the maintenance of DNA integrity and stability, and in chromatin modifications, and aberrant or dysregulation of DNA methylation has been mechanistically linked to the development of human diseases including cancer.

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The inability to reposition or retrieve balloon-expandable transcatheter aortic valves once they have been deployed requires implantation of the valve in the descending aorta or open surgical procedures to extract the valve. We describe the challenging transfemoral delivery of an Edwards Lifesciences Sapien valve wherein we had difficulty crossing the aortic valve and the guidewire position was compromised. We performed a transapical puncture to snare the guidewire and create a left ventricular to femoral wire rail, allowing us to deliver the transfemoral transcatheter valve, salvaging a situation where we would have been required to implant the valve in the descending aorta.

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Cardiogenic shock (CS) in the setting of acute myocardial infarction is associated with high in-hospital mortality rates. Society guidelines provide a Class Ib recommendation for the use of hemodynamic support devices in patients with CS following ST-elevation myocardial infarction. Exchanging of hemodynamic support devices is often complicated by inability to maintain percutaneous vascular access upon device removal in the setting of anticoagulation.

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Patent foramen ovale (PFO) is a common developmental anomaly that allows for the passage of blood and other substances from the venous to the arterial circulation. The study of PFO closure has been challenging due to widely available off-label closures performed outside the clinical trial setting. To date, no study has demonstrated benefit of closure using intention-to-treat analyses.

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Study Design: This was a retrospective study of patients who had developed a dural tear after thoracic and lumbar spine surgery that was not recognized during the surgery, and was treated either by lumbar drainage or over-sewing of the wounds.

Purpose: To revisit the treatment strategies in postoperative dural leaks and present our experience with over-sewing of the wound and lumbar drainage.

Overview Of Literature: Unintended durotomy is a frequent complication of spinal surgery.

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The "environmental dependency syndrome" refers to a loss of personal autonomy such that a person's environment almost entirely controls their actions. The goal of this study is to learn if patients with frontotemporal degeneration (FTD) exhibit prolonged TV watching, a behavior which may be a symptom of environmental dependency. We recruited 40 patients with FTD and 48 patients with Alzheimer's disease (AD), and asked these participants' caregivers about TV watching behaviors including total viewing time and channel/show preference, along with other behaviors indicative of environmental dependency.

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