Publications by authors named "Juhong Lee"

A structural adhesive series of biomass-based polyurethane (Biomass-PU) is synthesized using polypropylene glycol (PPG2000), isosorbide-based polyol (RPO300) as polyols, isophorone diisocyanate (IPDI) as an isocyanate and 4-tert-butylphenol (BP) as a capping agent. Three different equivalent ratios of PPG2000/RPO300, 9/1 (Biomass-PU1), 7/3 (Biomass-PU2), and 1/1 (Biomass-PU3), are evaluated to determine the effect of isosorbide-based polyol content on the properties and the optimizing formulation of biomass-PU structure adhesive. The 9/1 ratio of PPG2000/RPO300 substantially leads to the improvement of impact strength by up to 35 MPa, and the PPG2000/RPO300 = 9/1 ratio exhibits better thermal properties and impact strength than those of other ratios.

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Urethane acrylate (UA) was synthesized from various di-polyols, such as poly(tetrahydrofuran) (PTMG, Mn = 1000), poly(ethylene glycol) (PEG, Mn = 1000), and poly(propylene glycol) (PPG, Mn = 1000), for use as a polymer binder for paint. Polymethyl methacrylate (PMMA) and UA were blended to form an acrylic resin with high transmittance and stress-strain curve. When PMMA was blended with UA, a network structure was formed due to physical entanglement between the two polymers, increasing the mechanical properties.

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Triol acrylic-urethane (t-AU) was synthesized from an addition reaction using trimethylolpropane, hexamethylene diisocyanate, and 2-hydroxyethyl methacrylate. The novel acrylic-urethane polymer was applied to a high-performance binder to prepare a reliable road marking paint. Acrylic-urethane polymer binder formulations were designed to optimize the effect of t-AU on the physical properties.

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Article Synopsis
  • Melatonin offers protective effects against toxicity caused by Cadmium (Cd), a common environmental pollutant, by reducing harmful oxidative stress and restoring mitochondrial function.
  • In cell studies, Cd exposure decreases the levels of mitoSTAT3, a key protein linked to mitochondrial health, but melatonin boosts its levels, helping to prevent cell damage and death.
  • In animal studies, melatonin also counteracts the adverse effects of Cd on mouse prostate tissue, highlighting its potential role in maintaining mitochondrial integrity during Cd-induced stress.
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Critical transition theory suggests that complex systems should experience increased temporal variability just before abrupt state changes. We tested this hypothesis in 763 patients on long-term hemodialysis, using 11 biomarkers collected every two weeks and all-cause mortality as a proxy for critical transitions. We find that variability-measured by coefficients of variation (CVs)-increases before death for all 11 clinical biomarkers, and is strikingly synchronized across all biomarkers: the first axis of a principal component analysis on all CVs explains 49% of the variance.

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In the current study, an acrylic polymer binder applicable to road signs was successfully developed by mixing various acrylic, acrylate-type, and photoinitiator-based monomer species at different acrylate series/silicone acrylate ratios. An amorphous acrylic monomer was used, and the distance between the polymers was increased to improve transparency. The binder was designed with the purpose of reducing the yellowing phenomenon due to resonance by excluding the aromatic ring structure, which is the main cause of yellowing.

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Polyurethane pressure-sensitive adhesives (PU-PSAs) with satisfactory tack, cohesion, and removability were newly developed through the synthetic process by reacting methylene diisocyanate, poly(ethylene glycol) (PEG), and a 1,4-butanediol chain extender based on the different HDI/HDI trimer ratios. The sticking properties of PU-PSAs depended on both the HDI/HDI trimer ratio and crosslinking-agent composition in the formulation. The molecular weight (MW) dependence of adhesion in PU-PSA was observed in the range of 1000 < Mn < 3000, suggesting that the increase in MW limits the pressure-sensitive adhesion of these samples.

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Background: The aim of this study is (1) to compare joint line (JL) restoration and clinical outcomes in revision TKA based on the contemporary prosthesis type and (2) to determine the restoration of posterior condylar offset (PCO) according to the use of a femoral offset stem.

Methods: Sixty knees that underwent revision TKA from April 2003 to December 2013 with a minimum of 1 year follow up were included. These were further subdivided into three groups according to prosthesis type: group I (2 mm offset), group II (4.

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The aim of this study was to test the clinical efficacy of TissueGene-C (TG-C), a cell and gene therapeutic for osteoarthritis consisting of non-transformed and transduced chondrocytes (3:1) retrovirally transduced to overexpress transforming growth factor-β1. A total of 163 Kellgren-Lawrence grade 3 patients with knee osteoarthritis were randomly assigned to receive intra-articular TG-C or placebo. Primary efficacy measures included criteria for subjective assessment by International Knee Documentation Committee (IKDC) and pain severity by Visual Analog Scale (VAS) for 52 weeks.

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The objective of this study is to assess the safety and efficacy of repeated intra-articular injection of high molecular weight hyaluronic acid (LBSA0103) at a 26-week interval, in patients with osteoarthritis of the knee. The study was an open-label, single arm, multicentre prospective trial conducted in patients with symptomatic knee osteoarthritis. The intervention consisted of two intra-articular injections of LBSA0103, with the second injection performed 26 weeks after the first injection.

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Background: This randomized, double-blind, multi-center, non-inferiority trial was conducted to assess the efficacy and safety of a cross-linked hyaluronate (XLHA, single injection form) compared with a linear high molecular hyaluronate (HMWHA, thrice injection form) in patients with symptomatic knee osteoarthritis.

Methods: Two hundred eighty seven patients with osteoarthritis (Kellgren-Lawrence grade I to III) were randomized to each group. Three weekly injections were given in both groups but two times of saline injections preceded XLHA injection to maintain double-blindness.

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Ethnopharmacology Relevance: A previous study indicated non-inferiority of GCSB-5 to celecoxib regarding efficacy and safety in treating OA; however, the gastrointestinal (GI) safety data was limited to 12 weeks. Accordingly, a longer term study with a larger number of patients was necessary to establish the GI safety of GCSB-5.

Aim Of Study: The primary goal was to determine the safety and efficacy of 24-week use of GCSB-5.

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Objective: To evaluate the relative efficacy and safety of extended-release tramadol HCl 75 mg/acetaminophen 650 mg (TA-ER) and immediate-release tramadol HCl 37.5 mg/acetaminophen 325 mg (TA-IR) for the treatment of moderate to severe acute pain following total knee replacement.

Methods: This phase III, double-blind, placebo-controlled, parallel-group study randomized 320 patients with moderate to severe pain (≥4 intensity on an 11 point numeric rating scale) following total knee replacement arthroplasty to receive oral TA-ER (every 12 hours) or TA-IR (every 6 hours) over a period of 48 hours.

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The localized type of tenosynovial giant cell tumor usually occurs on the palmar side of fingers and toes. Tenosynovial giant cell tumors of the tendon sheath are rarely intra-articular. We report a giant cell tumor of the tendon sheath arising from femoral attachment of the anterior cruciate ligament and its treatment with arthroscopy in a 28-year-old man.

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Pathological diagnosis is influenced by subjective factors such as the individual experience and knowledge of doctors. Therefore, it may be interpreted in different ways for the same symptoms. The appearance of digital pathology has created good foundation for objective diagnoses based on quantitative feature analysis.

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Generally, pathological diagnosis using an electron microscope is time-consuming and likely to result in a subjective judgment, because pathologists perform manual screening of tissue slides at high magnifications. Recently, the advent of digital pathology technology has provided the basis for convenient screening and quantitative analysis by digitizing tissue slides through a computer system. However, a screening process with high magnification still takes quite a long time.

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Most reports on the use of modular femoral stems during revision surgery have involved short follow-up periods. The authors evaluated the clinical and radiographic performance of 59 patients fitted with a distal fix modular stem. The average follow-up period was 8.

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