Publications by authors named "May Kuen Lee"

Optimal fluid management during major surgery is of considerable concern to anesthesiologists. Although crystalloids are the first choice for fluid management, the administration of large volumes of crystalloids is associated with poor postoperative outcomes. Albumin can be used for fluid management and may protect renal function.

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Interest in multifunctional polymer nanoparticles for targeted delivery of anti-cancer drugs has grown significantly in recent years. In this study, tumor-targeting echogenic polymer micelles were prepared from poly(ethylene glycol) methyl ether-alkyl carbonate (mPEG-AC) derivatives, and their potential in cancer therapy was assessed. Various mPEG derivatives with carbonate linkages were synthesized via an alkyl halide reaction between mPEG and alkyl chloroformate.

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Multi-functional polymer nanoparticles have been widely utilized to improve cellular uptake and enhance therapeutic efficacy. In this study, it is hypothesized that the cellular uptake of poly(D,L-lactide-co-glycolide) (PLG) nanoparticles loaded with calcium carbonate minerals into adipocytes can be improved by covalent modification with nona-arginine (R ) peptide. It is further hypothesized that the internalization mechanism of R -modified PLG nanoparticles by adipocytes may be contingent on the concentration of R peptide present in the nanoparticles.

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The objective of this study was to evaluate the effects of high levels of maternal exposure to ambient air pollution and heavy metals on risks of autism spectrum disorder (ASD) and epilepsy using the National Health Insurance claims data of South Korea. The data of mothers and their newborns from 2016 to 2018 provided by the National Health Insurance Service were used ( = 843,134). Data on exposure to ambient air pollutants (PM2.

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The demand for body fat reduction is increasing. However, conventional lipolytic approaches fail to control adipose tissue reduction and cause severe side effects in adjacent nonadipose tissues. A strategy to specifically reduce subcutaneous fat using adipocytolytic polymer nanoparticles in a minimally invasive manner is reported here.

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A new anticancer strategy to exploit abnormal metabolism of cancer cells rather than to merely control the drug release or rearrange the tumor microenvironment is reported. An antiglycolytic amphiphilic polymer, designed considering the unique metabolism of cancer cells (Warburg effect) and aimed at the regulation of glucose metabolism, is synthesized through chemical conjugation between glycol chitosan (GC) and phenylboronic acid (PBA). GC-PBA derivatives form stable micellar structures under physiological conditions and respond to changes in glucose concentration.

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Hydrogels have been frequently employed for three-dimensional (3D) printing, which is a promising tool for fabricating sophisticated structures useful in many biomedical applications. Ferrogels prepared by combining magnetic nanoparticles with hydrogels also have potential in biomedical engineering because of the responsiveness to a magnetic field and remotely controllable properties. However, typical ferrogels, especially those prepared from natural polysaccharides, have limitations concerning their mechanical properties and the fabrication method of complex structures owing to their rigid and brittle properties.

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Hydrogels have been widely exploited as inks for three-dimensional (3D) bioprinting, a useful technique for building complex biological structures with living cells. However, hydrogels have inherently limited mechanical properties (e.g.

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Stem cells exist and maintain their quiescence and pluripotency in stem cell niche. Here, we hypothesized that regulation of cell-cell interactions using a polymeric scaffold as synthetic extracellular matrix (ECM) could be critical in creating a hematopoietic stem cell (HSC) niche in vitro. Angiopoietin-1 (Ang1) binds to the tyrosine kinase receptor (Tie2), and regulation of the Tie2/Ang1 interaction is important in maintaining the quiescence of HSCs in vivo.

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Tamoxifen (TAM), a selective oestrogen receptor modulator, is one of the most used treatments in oestrogen receptor-positive (ER+) early and metastatic breast cancer (BC) patients. The response to TAM has a high degree of inter-individual variability. This is mainly due to genetic variants in gene, as well as other genes encoding proteins involved in the TAM pharmacokinetic and/or pharmacodynamic.

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Three-dimensional (3D) bioprinting technique is useful to fabricate constructs with functional and biological structures for various biomedical applications. Oxidized hyaluronate (OHA) and glycol chitosan (GC) can form autonomous self-healing hydrogels when adipic acid dihydrazide (ADH) is used. We demonstrate that hyaluronate-alginate hybrid (HAH) polymers can be used for secondary physical cross-linking of OHA/GC/ADH hydrogel with calcium ions after 3D printing.

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Background: Early identification of patients at risk of AKI after cardiac surgery is of critical importance for optimizing perioperative management and improving outcomes. This study aimed to identify the association between preoperative myoglobin levels and postoperative acute kidney injury (AKI) in patients undergoing valve surgery or coronary artery bypass graft surgery (CABG) with cardiopulmonary bypass.

Methods: This retrospective study included 293 patients aged over 17 years who underwent valve surgery or CABG with cardiopulmonary bypass.

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Hydrogels have been widely utilized in tissue engineering applications as functional and biological synthetic extracellular matrices (ECMs) can be created with gels. However, typical hydrogels cannot be exploited in 3D printing, especially in extrusion printing, unless post-cross-linking after printing is provided. Additionally, dynamic tissue scaffolds that can mimic ECM environments in the body have been demonstrated to be useful in tissue engineering.

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The utilization of cell-manipulating techniques reveals information about biological behaviors suited to address a wide range of questions in the field of life sciences. Here, we introduced an on/off switchable physical stimuli technique that offers precise stimuli for reversible cell patterning to allow regulation of the future direction of adherent cellular behavior by leveraging enzymatically degradable alginate hydrogels with defined chemistry and topography. As a proof of concept, targeted muscle cells adherent to TCP exhibited a reshaped structure when the hydrogel-based physical stimuli were applied.

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Background: Functional degradation among community-dwelling patients with schizophrenia can negatively influence their recovery. Given the importance of patient empowerment during recovery, this study examined the mediating effect of empowerment on the relationship between global function and personal recovery among community-dwelling patients with schizophrenia.

Methods: This cross-sectional study recruited community-dwelling patients with schizophrenia from northern and central Taiwan.

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Spinal cord stimulation (SCS) has been used to treat sustained pain that is intractable despite various types of treatment. However, conventional tonic waveform SCS has not shown promising outcomes for spinal cord injury (SCI) or postamputation pain. The pain signal mechanisms of burst waveforms are different to those of conventional tonic waveforms, but few reports have presented the therapeutic potential of burst waveforms for the abovementioned indications.

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Hydrogel systems that show self-healing ability after mechanical damage are receiving increasing attention. However, self-healing hydrogels suitable for biomedical applications are limited owing to complex preparation methods. Furthermore, few studies have demonstrated the self-healing property of ferrogels.

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Modulation of the viscoelastic properties of hydrogels is critical in tissue engineering applications. In the present study, a hyaluronate-alginate hybrid (HAH) was synthesized by introducing alginate to the hyaluronate backbone with varying molecular weights (700-2500 kDa), and HAH hydrogels were prepared in the presence of calcium ions at the same cross-linking density. The storage shear moduli of the HAH hydrogels increased with the concomitant increase in the molecular weight of hyaluronate in the HAH polymer.

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Glioblastoma multiforme (GBM) is an aggressive tumor with no curative treatment. The tumor recurrence after resection often requires chemotherapy or radiation to delay the infiltration of tumor remnants. Intracerebral chemotherapies are preferentially being used to prevent tumor regrowth, but treatments remain unsuccessful because of the poor drug distribution in the brain.

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Stimulus-responsive drug delivery systems have been widely used for many biomedical applications. Magnetic stimulation may serve as an important external stimulus for drug delivery. In this study, we hypothesized that the on-demand release of anticancer drugs could be achieved with a macroporous alginate ferrogel under the influence of magnetic stimulation to enhance therapeutic efficacy in a tumor-bearing mouse model.

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Tissue engineering typically requires a use of scaffolds when delivering tissue-specific cells to be engineered. Hydrogels are frequently used as scaffolds, because their composition, structure, and function resemble the natural tissue extracellular matrix. In this study, hyaluronate-alginate hybrid (HAH) was synthesized by conjugating alginate (ALG) with the hyaluronate (HA) backbone using various types of linkers.

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Development of biomaterial-based bioinks is critical for replacement and/or regeneration of tissues and organs by three-dimensional (3D) printing techniques. However, the number of 3D-printable biomaterials in practical use remains limited despite the rapid development of 3D printing techniques. Controlling the flow properties of bioinks and mechanical properties of the resultant printed objects is key considerations in the design of biomaterial-based bioinks for practical applications.

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Objective: The dose of neuromuscular blocking drugs is commonly based on body weight, but using muscle mass might be more effective. This study investigated the relationship between the effect of neuromuscular blocking drugs and muscle mass measured using bioelectrical impedance analysis.

Methods: Patients who were scheduled for elective surgery using a muscle relaxant were screened for inclusion in this study.

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Pressure injury is a serious problem and is common in critical care units. Over the last decade, there is new evidence suggesting that the use of multilayered silicone foam dressing as preventive measures can decrease the incidence and prevalence rate of hospital-acquired pressure injury. The purpose of this study was to investigate the clinical efficacy of this dressing in reducing sacral and coccygeal pressure injury incidence rate as compared with standard preventive interventions in critical care settings.

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Hyaluronate-based hydrogels have been widely exploited as synthetic extracellular matrices in many tissue engineering applications, including cartilage tissue engineering. Hyaluronate-based hydrogels are typically prepared by chemical cross-linking reactions, in which chemical reagents may induce side effects, unless they are completely removed after the cross-linking reaction. We thus suggest the utilization of hybrid materials composed of hyaluronate as a main chain and alginate for physical cross-linking to simply form hydrogels in the presence of calcium ions under physiological conditions.

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