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1.
Int J Mol Sci ; 24(22)2023 Nov 17.
Article En | MEDLINE | ID: mdl-38003661

This study is designed to formulate and characterize chitosan-based nanogels that provide the controlled delivery of anesthetic drugs, such as bupivacaine (BPV), for effective postoperative pain management over prolonged periods of time. Drug carriers of chitosan/poly (MMA-co-HEMA-cl-EGDMA) (CsPMH) nanogels were prepared by varying the composition of comonomers such as MMA, HEMA, and redox initiator CAN. The nanogels were then characterized using FTIR, TGA, SEM, and TEM. The CsPMH nanogels showed greater encapsulation efficiencies from 43.20-91.77%. Computational studies were also conducted to evaluate the interaction between the drug and CsPMH nanoparticles. Finally, BPV-loaded nanoparticles were used to examine their in vitro release behavior. At pH 7.4, all the drug carriers displayed the "n" value around 0.7, thus the BPV release follows anomalous diffusion. Drug carrier 7 demonstrated a steady and sustained release of BPV for approximately 24 h and released about 91% of BPV, following the K-P mechanism of drug release. On the other hand, drug carrier 6 exhibited controlled release for approximately 12 h and released only 62% of BPV.


Chitosan , Nanoparticles , Nanogels , Chitosan/chemistry , Bupivacaine , Drug Carriers/chemistry , Hydrogen-Ion Concentration
2.
Nano Lett ; 23(13): 5934-5942, 2023 Jul 12.
Article En | MEDLINE | ID: mdl-37382460

Herein, we highlight a novel finding that ferritin can play a crucial role in the "self-healing lifetime" of soft phenolic materials. Ferritin interacts with a catechol-functionalized polymer to form a self-healable and adhesive hydrogel bidirectionally by providing and retrieving Fe3+. As a result of its unique role as a nanoshuttle to store and release iron, ferritin significantly increases the self-healing lifetime of the hydrogel compared with that afforded by catechol-Fe3+ coordination through direct Fe3+ addition without ferritin. Ferritin also induces stable oxidative coupling between catechol moieties following metal coordination, which contributes to double cross-linking networks of catechol-catechol adducts and catechol-Fe3+ coordination. Thus, ferritin-mediated cross-linking can provide phenolic hydrogels with the advantages of hydrogels prepared by both metal coordination and oxidative coupling, thereby overcoming the limitations of the current cross-linking methods of phenolic hydrogels and broadening their versatility in biomedical applications.

3.
Front Oncol ; 11: 636378, 2021.
Article En | MEDLINE | ID: mdl-34150613

BACKGROUND: Although the guidelines recommend gynecological assessment and close monitoring for symptoms of endometrial cancer in postmenopausal breast cancer survivors taking tamoxifen (TAM), the risk of endometrial cancer in young breast cancer survivors has not yet been fully assessed. This study aimed to investigate the risk of developing endometrial cancer and the frequencies of gynecological examinations in young breast cancer survivors taking TAM in South Korea. METHODS: A nationwide retrospective cohort study was conducted using the Health Insurance Review and Assessment Service claims data. Kaplan-Meier analyses and log-rank tests were used to assess the probability of endometrial cancer, benign endometrial conditions, and the probability of invasive endometrial procedure. To analyze the risk of endometrial cancer and benign endometrial conditions, we used a multivariable Cox proportional hazards regression model. RESULTS: Between 2010 and 2015, 60,545 newly diagnosed female breast cancer survivors were included. The total person-years were 256,099 and 140 (0.23%) patients developed endometrial cancer during the study period. In breast cancer survivors aged ≥60 years [hazard ratio (HR), 5.037; 95% confidence interval (CI), 2.185-11.613], 50-59 years (HR, 4.343; 95% CI, 2.122-8.891), and 40-49 years (HR, 2.121; 95% CI, 1.068-4.213), TAM was associated with an increased risk of endometrial cancer. In subjects aged below 40 years, TAM did not significantly increase the risk of endometrial cancer. However, among the TAM subgroups, breast cancer survivors aged below 40 years [1.61 per 1,000 person-years (PY); HR, 12.460; 95% CI, 2.698-57.522] and aged 40-49 years (2.22 per 1,000 PY; HR, 9.667; 95% CI, 4.966-18.819) with TAM-related endometrial diseases showed significantly increased risks of endometrial cancer. Among the TAM subgroup with benign endometrial conditions, the ratios of the frequency of invasive diagnostic procedures to the incidence of endometrial cancer were higher in subjects under 40 than subjects aged 60 or more. CONCLUSION: Young breast cancer survivors with TAM-related benign endometrial diseases are at a higher risk of developing endometrial cancer. Gynecological surveillance should be tailored to the risk of endometrial cancer in young breast cancer survivors to improve the early detection of endometrial cancer and avoid unnecessary invasive procedures.

4.
J Breast Cancer ; 24(3): 349-355, 2021 Jun.
Article En | MEDLINE | ID: mdl-33818019

Tumor localization is challenging in the context of ductal carcinoma in situ (DCIS) treated with breast-conserving surgery. Conventional localization methods are generally performed under the guidance of ultrasonography or mammography and are rarely performed with magnetic resonance imaging (MRI), which is more sensitive than the aforementioned modalities in detecting DCIS. Here, we report the application of MRI-based individualized 3-dimensional (3D)-printed breast surgical guides (BSGs) for patients with breast cancer. We successfully resected indeterminate and suspicious lesions that were only detected using preoperative MRI, and the final histopathologic results confirmed DCIS with clear resection margins. MRI guidance combined with 3D-printed BSGs can be used for DCIS localization, especially for lesions easily detectable using MRI only.

5.
ACS Biomater Sci Eng ; 7(9): 4230-4243, 2021 09 13.
Article En | MEDLINE | ID: mdl-33538598

Chondroitin sulfate (CS), the main component of cartilage extracellular matrix, has attracted attention as a biomaterial for cartilage tissue engineering. However, current CS hydrogel systems still have limitations for application in successful cartilage tissue engineering owing to their unsuitable degradation kinetics, insufficient mechanical similarity, and lack of integration with the native cartilage tissue. In this study, using mussel adhesive-inspired catechol chemistry, we developed a functional CS hydrogel that exhibits tunable physical and mechanical properties as well as excellent tissue adhesion for efficient integration with native tissues. Various properties of the developed catechol-functionalized CS (CS-CA) hydrogel, including swelling, degradation, mechanical properties, and adhesiveness, could be tailored by varying the conjugation ratio of the catechol group to the CS backbone and the concentration of the CS-CA conjugates. CS-CA hydrogels exhibited significantly increased modulus (∼10 kPa) and superior adhesive properties (∼3 N) over conventional CS hydrogels (∼hundreds Pa and ∼0.05 N). In addition, CS-CA hydrogels incorporating decellularized cartilage tissue dice promoted the chondrogenic differentiation of human adipose-derived mesenchymal stem cells by providing a cartilage-like microenvironment. Finally, the transplantation of autologous cartilage dice using tissue-adhesive CS-CA hydrogels enhanced cartilage integration with host tissue and neo-cartilage formation owing to favorable physical, mechanical, and biological properties for cartilage formation. In conclusion, our study demonstrated the potential utility of the CS-CA hydrogel system in cartilage tissue reconstruction.


Hydrogels , Tissue Adhesives , Cartilage , Chondroitin Sulfates , Humans , Tissue Engineering
6.
J Breast Cancer ; 24(6): 569-577, 2021 Dec.
Article En | MEDLINE | ID: mdl-34979601

PURPOSE: Intraoperative frozen section biopsy is used to reduce the margin positive rate and re-excision rate and has been reported to have high diagnostic accuracy. A majority of breast surgeons in the Republic of Korea routinely perform frozen section biopsy to assess margins intraoperatively, despite its long turnaround time and high resource requirements. This study aims to determine whether omitting frozen section biopsy for intraoperative margin evaluation in selected patients is non-inferior to performing frozen section biopsy in terms of resection margin positivity rate. METHODS: This study is a phase III, randomized controlled, parallel-group, multicenter non-inferiority clinical trial. Patients meeting the inclusion criteria and providing written informed consent will be randomized to the "frozen section biopsy" or "frozen section biopsy omission" group after lumpectomy. Patients with clinical stage T1-T3 disease who are diagnosed with invasive breast cancer by core-needle biopsy and plan to undergo breast-conserving surgery will be included in this study. If a daughter nodule, non-mass enhancement, or microcalcification is identified on preoperative imaging, these features must be within 1 cm of the main mass for inclusion in the trial. The target sample size is 646 patients per arm. The primary endpoint will be the resection margin positive rate, and the secondary endpoints include the reoperation rate, operating time, residual cancer after reoperation, residual cancer after re-excision according to the frozen section biopsy result, resection volume, patient quality of life, and cost-effectiveness. DISCUSSION: This is the first randomized clinical trial utilizing frozen section biopsy for intraoperative margin evaluation and aims to determine the non-inferiority of omitting frozen section biopsy in selected patients compared to performing frozen section biopsy. We expect that this trial will help surgeons perform the procedure more efficiently while ensuring patient safety. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03975179; Clinical Research Information Service Identifier: KCT0004606.

7.
Sci Rep ; 10(1): 19136, 2020 11 05.
Article En | MEDLINE | ID: mdl-33154535

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS)-based serum N-glycan analysis has gained acknowledgment for the diagnosis of breast cancer in recent years. In this study, the possibilities of expanding its application for breast cancer management and surveillance were discovered and evaluated. First, a novel MALDI-TOF platform, IDsys RT, was confirmed to be effective for breast cancer analysis, showing a maximum area under the curve of 0.91. Multiple N-glycan markers were identified and validated using this process, and they were found to be applicable for differentiating recurring breast cancer samples from healthy control or ordinary breast cancer samples. Recurrence samples were especially distinct from non-recurrence samples when N-glycan signatures were sampled in multiple time points and monitored via MALDI-TOF, throughout the therapy. These results suggested the feasibility of MALDI-TOF-based N-glycan analysis for tracking the molecular signatures of breast cancer and predicting recurrence.


Breast Neoplasms/diagnosis , Neoplasm Recurrence, Local/diagnosis , Polysaccharides/metabolism , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods , Adult , Biomarkers/metabolism , Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Female , Humans , Middle Aged , Neoplasm Recurrence, Local/metabolism , Neoplasm Recurrence, Local/pathology
8.
Article En | MEDLINE | ID: mdl-33182521

Chronic rhinosinusitis is known to be influenced by cigarette exposure; however, this relationship is based on the presence of nasal polyps, and objective measurements of cigarette exposure in chronic rhinosinusitis are not well established. This study aimed to estimate the association between chronic rhinosinusitis and smoking status based on self-reported questionnaires and urinary cotinine levels according to the presence of nasal polyps. We analyzed a total of 23,621 participants who participated from the fifth Korea National Health and Nutrition Examination Survey (2010-2012). Serum total and specific IgE level were measured. Higher prevalence of chronic rhinosinusitis with nasal polyps was associated with current smoking status (OR = 1.43, 95% CI = 1.00-2.03). This association was prevalent in participants aged ≤ 50 years (OR = 1.76, 95% CI = 1.01-3.05), and higher urinary cotinine level showed correlation with higher prevalence of chronic rhinosinusitis with nasal polyps in this age group (OR = 1.04, 95% CI = 1.00-1.08). In addition, positive correlation between serum total IgE and urinary cotinine levels was greater in patients with chronic rhinosinusitis (ß = 0.493, 95% CI = 0.071-0.916) than in controls (ß = 0.062, 95% CI = 0.021-0.103). Aggressive smoking interventions should be performed in patients with chronic rhinosinusitis with nasal polyp, especially in cases of young adults or high serum IgE levels.


Rhinitis , Tobacco Products , Chronic Disease , Cotinine , Humans , Nutrition Surveys , Republic of Korea/epidemiology , Rhinitis/epidemiology , Young Adult
9.
J Control Release ; 327: 571-583, 2020 11 10.
Article En | MEDLINE | ID: mdl-32905801

Bio-inspired adhesive hydrogels have been applied to cell and drug delivery systems to address various tissue defects and disorders. However, adhesive hydrogels functionalized with phenolic moieties often lack osteoconductive capacity and mechanical properties for bone regeneration. In this study, we utilized the versatile chemical interactions of phenolic moieties to overcome such limitations in bone tissue engineering efforts. Highly osteoconductive hybrid hydrogel patches were fabricated by incorporating inorganic minerals, hydroxyapatite (HAP), or whitlockite (WKT), into pyrogallol-conjugated hyaluronic acid (HA-PG). The hybrid HA-PG patches exhibited improved mechanical strength and reinforced structural/physical properties owing to additional intermolecular complexation between oxidized PG moieties and ions released from inorganic particles. The sustained release of bone morphogenetic protein-2 (BMP-2) from hybrid patches was prolonged by combination of the inherent nucleophilic affinity of oxidized PG and electrostatic interactions between inorganic particles and BMP-2. With increased osteoconductivity, hybrid patches with HAP or WKT enhanced the osteogenic differentiation of human stem cells while also promoting new bone formation in a critical-sized calvarial defect. Our study demonstrates a translational potential of phenolic adhesive hydrogels engineered with inorganic minerals for orthopedic applications.


Hydrogels , Osteogenesis , Bone Morphogenetic Protein 2 , Bone Regeneration , Durapatite , Humans , Hyaluronic Acid
10.
J Breast Cancer ; 23(2): 224-229, 2020 04.
Article En | MEDLINE | ID: mdl-32395381

We report a case of recurrence as Paget's disease at the core needle biopsy (CNB) entry site in a patient with microinvasive ductal carcinoma who underwent nipple-areola-skin sparing mastectomy (NASSM) and autologous reconstruction. Clinically diagnosed recurrences associated with previous needle procedures for malignant breast lesions are rare and usually occur in patients who have not received radiation therapy. The present case involved local recurrence at the skin puncture site of a patient diagnosed based on CNB findings who underwent NASSM without receiving radiation therapy. Although the removal of the CNB tract with resected breast tissue is not always emphasized, the skin puncture site should be recorded to detect abnormal skin changes after surgery for the timely detection and management of complications.

11.
Cell Metab ; 17(1): 61-72, 2013 Jan 08.
Article En | MEDLINE | ID: mdl-23312284

Vascular endothelial growth factor A (VEGF) is highly expressed in adipose tissue. Its role, however, has not been fully elucidated. Here, we reveal the metabolic role of adipose-VEGF by studying mice with deletion (VEGF(AdΔ)) or doxycycline-inducible overexpression of a VEGF transgene (VEGF(AdTg)) in the adipose tissue. VEGF(AdΔ) mice have reduced adipose vascular density and show adipose hypoxia, apoptosis, inflammation, and metabolic defects on a high-fat diet. In contrast, induction of VEGF expression in VEGF(AdTg) mice leads to increased adipose vasculature and reduced hypoxia. The latter changes are sufficient to counteract an established compromising effect of high-fat diet on the metabolism, indicating that metabolic misbalance is reversible by adipose vessel density increase. Our data clearly show the essential role of VEGF signaling for adequate adipose function. Besides revealing insights into the molecular mechanisms of obesity-related metabolic diseases, this study points to the therapeutic potential of increased adipose angiogenesis.


Adipose Tissue/metabolism , Neovascularization, Physiologic/physiology , Vascular Endothelial Growth Factor A/metabolism , Adipokines/metabolism , Adipose Tissue/blood supply , Adipose Tissue/drug effects , Animals , Apoptosis , Diet, High-Fat , Doxycycline/pharmacology , Glucose Intolerance/metabolism , Glucose Intolerance/pathology , Inflammation/metabolism , Inflammation/pathology , Insulin Resistance , Macrophages/immunology , Macrophages/physiology , Mice , Mice, Transgenic , Models, Animal , Signal Transduction , Vascular Endothelial Growth Factor A/genetics
12.
J Med Chem ; 53(9): 3696-706, 2010 May 13.
Article En | MEDLINE | ID: mdl-20361800

To enhance the ability of indirubin derivatives to inhibit CDK2/cyclin E, a target of anticancer agents, we designed and synthesized a new series of indirubin-3'-oxime derivatives with combined substitutions at the 5 and 5' positions. A molecular docking study predicted the binding of derivatives with OH or halogen substitutions at the 5' position to the ATP binding site of CDK2, revealing the critical interactions that may explain the improved CDK2 inhibitory activity of these derivatives. Among the synthesized derivatives, the 5-nitro-5'-hydroxy analogue 3a and the 5-nitro-5'-fluoro analogue 5a displayed potent inhibitory activity against CDK2, with IC(50) values of 1.9 and 1.7 nM, respectively. These derivatives also showed antiproliferative activity against several human cancer cell lines, with IC(50) values of 0.2-3.3 microM. A representative analogue, 3a, showed greater than 500-fold selectivity for CDK relative to selected kinase panel and potent in vivo anticancer activity.


Antineoplastic Agents/chemistry , Cyclin-Dependent Kinase 2/antagonists & inhibitors , Cyclin-Dependent Kinase Inhibitor Proteins/therapeutic use , Oximes/pharmacology , Adenosine Triphosphate , Binding Sites , Cell Line, Tumor , Cyclin-Dependent Kinase Inhibitor Proteins/pharmacology , Drug Design , Humans , Indoles , Structure-Activity Relationship
13.
Yonsei Med J ; 51(3): 460-2, 2010 May.
Article En | MEDLINE | ID: mdl-20376904

Type B lactic acidosis is a rare condition in patients with solid tumors or hematological malignancies. Although there have been several theories to explain its mechanism, the exact cause of lactic acidosis remains to be discovered. Lactic acidosis is usually related to increased tumor burden in patients with malignancy. We experienced a case of lactic acidosis in a 39-year-old man who visited an emergency room because of dyspnea, and the cause of lactic acidosis turned out to be recurrent acute leukemia. Chemotherapy relieved the degree of lactic acidosis initially, but as the disease progressed, lactic acidosis became aggravated. Type B lactic acidosis can be a clinical presentation of acute exacerbation of acute leukemia.


Acidosis, Lactic/diagnosis , Leukemia/complications , Acidosis, Lactic/etiology , Acute Disease , Adult , Humans , Male
14.
Eur J Med Chem ; 45(6): 2578-90, 2010 Jun.
Article En | MEDLINE | ID: mdl-20303626

BACE-1 has been shown to be an attractive therapeutic target in Alzheimer's disease (AD). Using a 1,4-dihydropyridine (DHP) scaffold, we synthesized new inhibitors of BACE-1 by modifying the known BACE inhibitor 2 containing a hydroxyethylamine (HEA) motif. Using structure-based drug design based on computer-aided molecular docking, the isophthalamide ring of 2 was replaced with a 1,4-dihydropyridine ring as a brain-targeting strategy. Several of the new dihydropyridine derivatives were synthesized and their BACE-1-inhibitory activities were evaluated using a cell-based, reporter gene assay system that measures the cleavage of alkaline phosphatase (AP)-APP fusion protein by BACE-1. Most of the 1,4-DHP analogs showed BACE-1-inhibitory activities with IC50 values in the range 8-30 microM, suggesting that the 1,4-DHP skeleton may be utilized to develop brain-targeting BACE-1 inhibitors.


Amyloid Precursor Protein Secretases/antagonists & inhibitors , Aspartic Acid Endopeptidases/antagonists & inhibitors , Dihydropyridines/chemical synthesis , Dihydropyridines/pharmacology , Drug Design , Amyloid Precursor Protein Secretases/chemistry , Amyloid Precursor Protein Secretases/metabolism , Aspartic Acid Endopeptidases/chemistry , Aspartic Acid Endopeptidases/metabolism , Cell Line , Dihydropyridines/chemistry , Dihydropyridines/metabolism , Inhibitory Concentration 50 , Models, Molecular , Molecular Conformation
15.
Ann Thorac Surg ; 87(2): 625-8, 2009 Feb.
Article En | MEDLINE | ID: mdl-19161799

Aortic regurgitation is not so rare in patients with Fabry disease. Enzyme replacement therapy has become the standard medical care for Fabry disease in recent years. A 31-year-old man with Fabry disease, treated with recombinant alpha-galactosidase enzyme replacement for 19 months was admitted for evaluation of exertional dyspnea. Cardiac workup revealed left ventricular hypertrophy, increased left ventricular size, and moderate to severe aortic regurgitation. He underwent mechanical valvular replacement and heart biopsy. Histology of his aortic valve showed myxoid degeneration of valve leaflets. His heart muscle revealed extensive hypertrophy with vacuolization and the absence of lamellar bodies. We report a case of Fabry disease with aortic regurgitation in a man who underwent valvular replacement operation during enzyme replacement therapy.


Aortic Valve Insufficiency/pathology , Aortic Valve Insufficiency/surgery , Bioprosthesis , Fabry Disease/complications , Heart Valve Prosthesis Implantation/methods , Adult , Aortic Valve Insufficiency/etiology , Biopsy, Needle , Fabry Disease/drug therapy , Fabry Disease/pathology , Follow-Up Studies , Humans , Immunohistochemistry , Male , Risk Assessment , Severity of Illness Index , Treatment Outcome , alpha-Galactosidase/therapeutic use
16.
Stem Cells Dev ; 18(3): 521-9, 2009 Apr.
Article En | MEDLINE | ID: mdl-18647091

The most commonly used therapeutic targets in nephrology are the reduction of injury, the delay of progression, or renal replacement therapy. Many animal and human studies demonstrated the role of stem cells in repair and regenerations of kidney. Mesenchymal stem cells (MSCs) have shown to improve outcome of acute renal injury models. It is controversial whether MSCs can reduce injury following a toxic/ischemic event and delay renal failure in chronic kidney disease. We evaluated the hypothesis that the treatment with MSCs could improve renal function and attenuate injury in chronic renal failure (CRF). Sprague-Dawley female rats (8 weeks old, 182.2 +/- 7.2 g) underwent modified 5/6 nephrectomy. Rats in the MSC group received an injection of MSCs (1 x 10(6) cells) via tail vein 1 day after nephrectomy. Blood and urine samples were collected after 7 days and every month thereafter. The kidneys of rats were removed for histologic evaluation after 24-h urine collection and blood sampling. The Y-chromosome stain using fluorescent in situ hybridization was performed to verify the presence of male MSCs in the kidney of female recipients. No significant differences in blood urea nitrogen and creatinine concentration were observed between the MSC group and the untreated CRF group. However, the weight gain in the MSC group was greater than those in the CRF group after 4 months. Proteinuria in the MSC group was less than that in the CRF group over time. Y chromosome was detected in the kidney of MSC group. Although no significances were observed between these two groups, the histologic analysis suggests that MSCs have positive effect against glomerulosclerosis. These results suggest that MSCs help preserve renal function and attenuate renal injury in CRF.


Cell- and Tissue-Based Therapy , Kidney Failure, Chronic/therapy , Mesenchymal Stem Cells/physiology , Animals , Blood Urea Nitrogen , Creatinine/urine , Disease Progression , Female , Humans , In Situ Hybridization, Fluorescence , Kidney/cytology , Kidney/metabolism , Kidney/pathology , Kidney Failure, Chronic/physiopathology , Male , Mesenchymal Stem Cell Transplantation , Mesenchymal Stem Cells/cytology , Nephrectomy , Rats , Rats, Sprague-Dawley , Transforming Growth Factor beta/blood , Vascular Endothelial Growth Factor A/blood
17.
Nano Lett ; 6(6): 1126-30, 2006 Jun.
Article En | MEDLINE | ID: mdl-16771566

Sulfur-doped zinc oxide (ZnO) nanowires grown on gold-coated silicon substrates inside a horizontal tube furnace exhibit remarkably strong visible wavelength emission with a quantum efficiency of 30%, an integrated intensity 1600 times stronger than band edge ultraviolet emission, and a spectral distribution that closely matches the dark-adapted human eye response. By comparatively studying sulfur-doped and undoped ZnO micropowders, we clarify how sulfur doping and nanostructuring affect the visible luminescence and the underlying energy transfer mechanisms.


Luminescence , Luminescent Measurements/instrumentation , Nanostructures/chemistry , Nanostructures/radiation effects , Sulfur/chemistry , Zinc Oxide/chemistry , Zinc Oxide/radiation effects , Equipment Design , Equipment Failure Analysis , Light , Luminescent Measurements/methods , Materials Testing , Molecular Conformation , Nanostructures/ultrastructure , Particle Size , Powders , Spectrometry, Fluorescence , Time Factors
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