Kyung-Soon Park

Bio: Kyung-Soon Park is an academic researcher from Chonnam National University. The author has contributed to research in topics: Harris Hip Score & Arthroplasty. The author has an hindex of 19, co-authored 133 publications receiving 1182 citations. Previous affiliations of Kyung-Soon Park include Wake Forest Institute for Regenerative Medicine.

Biomechanical analysis of the effects of medial meniscectomy on degenerative osteoarthritis.

Abstract: To investigate the effects of meniscectomy on degenerative osteoarthritis, a three-dimensional (3D) finite element (FE) model of the human lower limb is constructed from a combination of magnetic resonance (MR) images and computed tomographic (CT) images that can provide anatomically suitable boundary conditions for a knee joint. Four cases, i.e., the intact meniscus, and the partial, sub-total, and total meniscectomy of the medial meniscus are modeled and simulated. We consider that the cartilage-to-cartilage contact area and the peak contact pressure in the meniscus may be significant parameters in evaluating degenerative osteoarthritis. Partial meniscectomy can be regarded as a better treatment than sub-total/total meniscectomy, and a high possibility of degenerative osteoarthritis is anticipated after total meniscectomy. Moreover, medial meniscectomy has the potential to bring about degenerative osteoarthritis in both the medial compartment and the lateral compartment of a knee joint.

Tetraarsenic hexoxide enhances generation of mitochondrial ROS to promote pyroptosis by inducing the activation of caspase-3/GSDME in triple-negative breast cancer cells.

Abstract: Although tetraarsenic hexoxide is known to exert an anti-tumor effect by inducing apoptosis in various cancer cells, its effect on other forms of regulated cell death remains unclear. Here, we show that tetraarsenic hexoxide induces the pyroptotic cell death through activation of mitochondrial reactive oxygen species (ROS)-mediated caspase-3/gasdermin E (GSDME) pathway, thereby suppressing tumor growth and metastasis of triple-negative breast cancer (TNBC) cells. Interestingly, tetraarsenic hexoxide-treated TNBC cells exhibited specific pyroptotic characteristics, including cell swelling, balloon-like bubbling, and LDH releases through pore formation in the plasma membrane, eventually suppressing tumor formation and lung metastasis of TNBC cells. Mechanistically, tetraarsenic hexoxide markedly enhanced the production of mitochondrial ROS by inhibiting phosphorylation of mitochondrial STAT3, subsequently inducing caspase-3-dependent cleavage of GSDME, which consequently promoted pyroptotic cell death in TNBC cells. Collectively, our findings highlight tetraarsenic hexoxide-induced pyroptosis as a new therapeutic strategy that may inhibit cancer progression of TNBC cells.

Causes of Aseptic Persistent Pain after Total Knee Arthroplasty.

Abstract: BACKGROUND Persistent pain after total knee arthroplasty (TKA) is dissatisfying to the patient and frustrating to the surgeon. The purpose of this study is to evaluate the aseptic causes and clinical course of intractable pain following TKA. METHODS Of the total 2,534 cases of primary TKA reviewed, 178 cases were classified as having aseptic persistent pain that was not resolved within 1 year after surgery. Except for the cases with periprosthetic fracture (56 knees), 122 cases of aseptic painful TKA were divided into two groups: intra-articular group (83 knees) and extra-articular group (39 knees). RESULTS In the intra-articular group, the main reasons for pain were aseptic loosening (n = 40), polyethylene wear (n = 16), instability (n = 10), recurrent hemarthrosis (n = 5), patellar maltracking (n = 4), tendon ruptures (n = 4), and stiffness (n = 2). In the extraarticular group, 10 knees (25.6%) were found to have nerve entrapment in the spine, 6 knees (15.4%) were found to have hip osteoarthritis or femoral head avascular necrosis. The reasons for persistent knee pain in the remaining 23 knees (59.0%) still remain elusive. CONCLUSIONS Persistent pain after TKA originated from pathology of extra-articular origin in a considerable number of cases in this study. Therefore, it is important to perform thorough preoperative evaluations to reduce pain resulting from extra-articular causes. Furthermore, meticulous surgical procedures and optimal alignment are required to reduce pain of intra-articular origin related to implant wear, instability, and patellar maltracking.

Combined CDK2 and CDK4/6 Inhibition Overcomes Palbociclib Resistance in Breast Cancer by Enhancing Senescence.

Abstract: Breast cancer represents the number one global cancer burden in women and the hormone receptor (HR)-positive subtype comprises approximately 70% of breast cancers. Unfortunately, acquired resistance ultimately occurs in almost all cases, even though cyclin-dependent kinase 4 and 6 (CDK4/6) inhibitors are a highly effective therapy for HR-positive/human epidermal growth factor receptor 2-negative subtype. Here, we investigated mechanisms of resistance to CDK4/6 inhibitor and potential therapeutic strategies using our palbociclib-resistant preclinical model. We observed that cyclin E was significantly overexpressed in palbociclib-resistant cells, and similar association was also confirmed in pleural effusion samples collected from HR-positive breast cancer patients. After confirmation of cyclin E-CDK2 interaction by co-immunoprecipitation, we demonstrated CDK2 inhibition combined with palbociclib synergistically suppressed proliferation of palbociclib-resistant cells and growth of palbociclib-resistant xenograft in mice. We also proved that enhancing C-MYC-mediated senescence is a novel mechanism behind the synergism created by targeting both CDK2 and CDK4/6. Furthermore, the clinical relevance of cyclin E as a therapeutic target was supported by significant association between CCNE1 overexpression and poor prognosis based on large-scale public gene expression data sets in HR-positive breast cancer patients. Therefore, we propose cyclin E-CDK2 signaling as a promising therapeutic target for overcoming cyclin E-associated resistance to CDK4/6 inhibitor.

Integrative Genomics Viewer

Abstract: Rapid improvements in sequencing and array-based platforms are resulting in a flood of diverse genome-wide data, including data from exome and whole-genome sequencing, epigenetic surveys, expression profiling of coding and noncoding RNAs, single nucleotide polymorphism (SNP) and copy number profiling, and functional assays. Analysis of these large, diverse data sets holds the promise of a more comprehensive understanding of the genome and its relation to human disease. Experienced and knowledgeable human review is an essential component of this process, complementing computational approaches. This calls for efficient and intuitive visualization tools able to scale to very large data sets and to flexibly integrate multiple data types, including clinical data. However, the sheer volume and scope of data pose a significant challenge to the development of such tools.

Overexpression of the Tobacco Tsi1 Gene Encoding an EREBP/AP2–Type Transcription Factor Enhances Resistance against Pathogen Attack and Osmotic Stress in Tobacco

Abstract: Using mRNA differential display analysis, we isolated a salt-induced transcript that showed a significant sequence homology with an EREBP/AP2 DNA binding motif from oilseed rape plants. With this cDNA fragment as a probe, cDNA clone Tsi1 (for Tobacco stress-induced gene1) was isolated from a tobacco cDNA library. RNA gel blot analysis indicated that transcripts homologous with Tsi1 were induced not only in NaCl-treated leaves but also in leaves treated with ethephon or salicylic acid. Transient expression analysis using a Tsi1::smGFP fusion gene in BY-2 cells indicated that the Tsi1 protein was targeted to the nucleus. Fusion protein of Tsi1 with GAL4 DNA binding domain strongly activated transcription in yeast, and the transactivating activity was localized to the 13 C-terminal amino acids of Tsi1. Electrophoretic mobility shift assays revealed that Tsi1 could bind specifically to the GCC and the DRE/CRT sequences, although the binding activity to the former was stronger than that to the latter. Furthermore, Agrobacterium-mediated transient expression and transgenic plants expressing Tsi1 demonstrated that overexpression of the Tsi1 gene induced expression of several pathogenesis-related genes under normal conditions, resulting in improved tolerance to salt and pathogens. These results suggest that Tsi1 might be involved as a positive trans-acting factor in two separate signal transduction pathways under abiotic and biotic stress.

Wall and Melzack's textbook of pain

Abstract: WALL AND MELZACK'S TEXTBOOK OF PAIN, revised under new editorial leadership, and with a host of new, multidisciplinary international contributors ...

Single-incision anterior approach for total hip arthroplasty on an orthopaedic table : The treatment of osteoarthritis of the hip 1920

Abstract: Dislocation remains the leading early complication of total hip arthroplasty; surgical approach and implant positioning have been recognized as factors influencing total hip arthroplasty stability. We describe a total hip arthroplasty technique done through a single, tissue sparing anterior approach that allows implantation of the femoral and acetabular components without detaching or sectioning any of the muscles and tendons around the hip joint. A series of 437 consecutive, unselected patients who had 494 primary total hip arthroplasty surgeries done through an anterior approach on an orthopaedic table from September 1996 to September 2004 was reviewed. There were 54 hybrid and 442 uncemented hips in the 437 patients (57 bilateral). The average patient age was 64 years. Radiographic analysis showed an average abduction angle of 42°, with 96% in the range of 35° to 50° abduction. The average cup anteversion was 19° with 93% within the target range of 10° to 25°. Postoperative leg length discrepancy averaged 3 ± 2 mm (range, 0-26 mm). Three patients sustained dislocations for an overall dislocation rate of 0.61%, and no patients required revision surgery for recurrent dislocation. There were 17 operative complications, including one deep infection, three wound infections, one transient femoral nerve palsy, three greater trochanter fracture, two femoral shaft fractures four calcar fractures, and three ankle fractures. Operative time averaged 75 minutes (range 40-150 minutes), and the average blood loss was 350 mL (range, 100-1300 mL). The mean hospital stay was 3 days (range, 1-17 days). The anterior approach on the orthopaedic table is a minimally invasive technique applicable to all primary hip patients. This technique allows accurate and reproducible component positioning and leg-length restoration and does not increase the rate of hip dislocation.

Nontraumatic Osteonecrosis of the Femoral Head: Where Do We Stand Today?: A 5-Year Update

Abstract: ➤ Although multiple theories have been proposed, no one pathophysiologic mechanism has been identified as the etiology for the development of osteonecrosis of the femoral head. However, the basic mechanism involves impaired circulation to a specific area that ultimately becomes necrotic.➤ A variety of nonoperative treatment regimens have been evaluated for the treatment of precollapse disease, with varying success. Prospective, multicenter, randomized trials are needed to evaluate the efficacy of these regimens in altering the natural history of the disease.➤ Joint-preserving procedures are indicated in the treatment of precollapse disease, with several studies showing successful outcomes at mid-term and long-term follow-up.➤ Studies of total joint arthroplasty, once femoral head collapse is present, have described excellent outcomes at greater than ten years of follow-up, which is a major advance and has led to a paradigm shift in treating these patients.➤ The results of hemiresurfacing and total resurfacing arthroplasty have been suboptimal, and these procedures have restricted indications in patients with osteonecrosis of the femoral head.