BACKGROUND: Various methods based on gold nanoparticles (AuNPs) have been applied to enhance the photothermal effect. Among these methods, combining gold nanoparticles and stem cells has been suggested as a new technique for elevating the efficiency of photothermal therapy (PT) in terms of enhancing tumor targeting effect. However, to elicit the efficiency of PT using gold nanoparticles and stem cells, delivering large amounts of AuNPs into stem cells without loss should be considered. METHODS: AuNPs, AuNPs-decorated silica nanoparticles, and silica-capped and AuNPs-decorated silica nanoparticles (SGSs) were synthesized and used to treat human mesenchymal stem cells (hMSCs). After evaluating physical properties of each nanoparticle, the concentration of each nanoparticle was estimated based on its cytotoxicity to hMSCs. The amount of AuNPs loss from each nanoparticle by exogenous physical stress was evaluated after exposing particles to a gentle shaking. After these experiments, in vitro and in vivo photothermal effects were then evaluated. RESULTS: SGS showed no cytotoxicity when it was used to treat hMSCs at concentration up to 20 lg/mL. After intravenous injection to tumor-bearing mice, SGS-laden hMSCs group showed significantly higher heat generation than other groups following laser irradiation. Furthermore, in vivo photothermal effect in the hMSC-SGS group was significantly enhanced than those in other groups in terms of tumor volume decrement and histological outcome. CONCLUSION Our results suggest that additional silica layer in SGSs could protect AuNPs from physical stress induced AuNPs loss. The strategy applied in SGS may offer a prospective method to improve PT.

Recently, various attempts have been made to apply diverse types of nanoparticles in biotechnology. Silica nanoparticles (SNPs) have been highlighted and studied for their selective accumulation in diseased parts, strong physical and chemical stability, and low cytotoxicity. SNPs, in particular, are very suitable for use in drug delivery and bioimaging, and have been sought as a treatment for ischemic diseases. In addition, mesoporous silica nanoparticles have been confirmed to efficiently deliver various types of drugs owing to their porous structure. Moreover, there have been innovative attempts to treat ischemic diseases using SNPs, which utilize the effects of Si ions on cells to improve cell viability, migration enhancement, and phenotype modulation. Recently, external stimulus-responsive treatments that control the movement of magnetic SNPs using external magnetic fields have been studied. This review addresses several original attempts to treat ischemic diseases using SNPs, including particle synthesis methods, and presents perspectives on future research directions.

Cell-based therapies have been used as promising treatments for several untreatable diseases. However, cellbased therapies have side effects such as tumorigenesis and immune responses. To overcome these side effects, therapeutic effects of exosomes have been researched as replacements for cell-based therapies. In addition, exosomes reduced the risk that can be induced by cell-based therapies. Exosomes contain biomolecules such as proteins, lipids, and nucleic acids that play an essential role in cell–cell and cell–matrix interactions during biological processes. Since the introduction of exosomes, those have been proven perpetually as one of the most effective and therapeutic methods for incurable diseases. Much research has been conducted to enhance the properties of exosomes, including immune regulation, tissue repair, and regeneration. However, yield rate of exosomes is the critical obstacle that should be overcome for practical cell-free therapy. Three-dimensional (3D) culture methods are introduced as a breakthrough to get higher production yields of exosomes. For example, hanging drop and microwell were well known 3D culture methods and easy to use without invasiveness. However, these methods have limitation in mass production of exosomes. Therefore, a scaffold, spinner flask, and fiber bioreactor were introduced for mass production of exosomes isolated from various cell types. Furthermore, exosomes treatments derived from 3D cultured cells showed enhanced cell proliferation, angiogenesis, and immunosuppressive properties. This review provides therapeutic applications of exosomes using 3D culture methods.

PURPOSE: To investigate the causes, clinical features and characteristics of food-dependent exercise-induced anaphylaxis (FDEIA) in Korea. METHODS: A retrospective medical chart review was performed on the patients diagnosed with anaphylaxis between 2007 and 2011 in 14 hospitals in Korea. Cases with FDEIA were subsequently identified among anaphylaxis patients, and subgroup analyses were done to assess clinical characteristics of FDEIA. RESULTS: A total of 62 subjects with FDEIA (male, 72.6%; aged 16 to 70 years) were enrolled in 10 hospitals. Wheat (69.3%) was the most common cause of FDEIA, followed by meat (8.1%), seafood (6.5%), and vegetables (6.5%). The clinical manifestations were cutaneous (100%), respiratory (64.5%), cardiovascular (61.3%), and gastrointestinal (9.7%), respectively. In severity assessment, approximately 40% of FDEIA were classified as severe anaphylaxis. Portable epinephrine auto-injector was prescribed to 17.2% of patients, and about one fifth of the patients experienced redevelopment of anaphylactic symptoms during follow-up period. There was no significant difference of age, gender, latent period, total immunoglobulin E, and past history of allergic disease between patients with severe anaphylaxis group and patients with mild-to-moderate group. CONCLUSION: Wheat is the most common cause of FDEIA in Korea. Because significant number of patients with FDEIA experienced anaphylactic symptoms after diagnosis of FDEIA, more comprehensive therapeutic and educational approaches will be required to prevent recurrent development of anaphylaxis.
Aged ; Anaphylaxis ; Epinephrine ; Follow-Up Studies ; Food Hypersensitivity ; Humans ; Immunoglobulin E ; Immunoglobulins ; Korea ; Meat ; Retrospective Studies ; Seafood ; Triticum ; Vegetables