1.Reconstruction of hand.
Kyungjin LEE ; Dongchul LEE ; Siyoung ROH ; Jinsoo KIM
Journal of the Korean Medical Association 2016;59(2):127-135
The characteristics of hand trauma are changing due to automation of industrial facilities, improved access to health care, and the aging population. Since the inception of hand surgery as a subspecialty, hand defects have been reconstructed with the restoration of the original functionality as the primary goal. With advancement and maturation of surgical techniques, however, restoration of aesthetics also began to take hold as an important aspect of hand surgery practice. After the first successful replantation of an amputated digit, the rapid development of microsurgical techniques had a significant impact on the field of reconstructive hand surgery. In the first two decades, the success of replantation was evaluated by the survival rate for a single operator or a specialized institution. These days, however, microsurgical techniques have been widely adopted, with digital replantation possible even for infants. In addition to various local flaps, the evolution of free flaps has vastly expanded the repertoire of reconstructive options for hand surgeons. With the wide variety of free flaps available, it is possible for a severely injured hand to be salvaged and restored to its original functional and aesthetic status. In South Korea, hand surgery is becoming an established profession with a separate subspecialty certification. Hand surgery has a bright outlook, with future research directed at new biocompatible materials and novel reconstructive methods.
Aging
;
Automation
;
Biocompatible Materials
;
Certification
;
Esthetics
;
Free Tissue Flaps
;
Hand*
;
Health Services Accessibility
;
Humans
;
Infant
;
Korea
;
Microsurgery
;
Replantation
;
Survival Rate
2.NK Cell-Based Immunotherapies in Cancer
Min Hwa SHIN ; Junghee KIM ; Siyoung A. LIM ; Jungwon KIM ; Seong-Jin KIM ; Kyung-Mi LEE
Immune Network 2020;20(2):e14-
With the development of technologies that can transform immune cells into therapeutic modalities, immunotherapy has remarkably changed the current paradigm of cancer treatment in recent years. NK cells are components of the innate immune system that act as key regulators and exhibit a potent tumor cytolytic function. Unlike T cells, NK cells exhibit tumor cytotoxicity by recognizing non-self, without deliberate immunization or activation. Currently, researchers have developed various approaches to improve the number and anti-tumor function of NK cells. These approaches include the use of cytokines and Abs to stimulate the efficacy of NK cell function, adoptive transfer of autologous or allogeneic ex vivo expanded NK cells, establishment of homogeneous NK cell lines using the NK cells of patients with cancer or healthy donors, derivation of NK cells from induced pluripotent stem cells (iPSCs), and modification of NK cells with cutting-edge genetic engineering technologies to generate chimeric Ag receptor (CAR)-NK cells. Such NK cell-based immunotherapies are currently reported as being promising anti-tumor strategies that have shown enhanced functional specificity in several clinical trials investigating malignant tumors. Here, we summarize the recent advances in NK cell-based cancer immunotherapies that have focused on providing improved function through the use of the latest genetic engineering technologies. We also discuss the different types of NK cells developed for cancer immunotherapy and present the clinical trials being conducted to test their safety and efficacy.
3.Effect of Potassium Iodide on Erythrosine-Mediated Photodynamic Therapy on Streptococcus Mutans Biofilms
Yongsoon KIM ; Howon PARK ; Juhyun LEE ; Haeni KIM ; Siyoung LEE
Journal of Korean Academy of Pediatric Dentistry 2022;49(3):321-328
The aim of this in-vitro study is to evaluate the effect of potassium iodide (KI) on erythrosine-mediated photodynamic therapy (PDT) against Streptococcus mutans biofilms. S. mutans ATCC 25175 was cultured to form a biofilm on a hydroxyapatite disk. After diluting erythrosine to 20 μM and KI to 10, 50, and 100 mM, respectively, PDT was performed. The number of surviving bacteria was calculated as colony forming units (CFU)/mL and the statistical significance of the difference between groups was confirmed by Bonferroni post-hoc analysis. Cell viability was visually evaluated using confocal laser scanning microscopy (CLSM). As a result of the experiment, a significant decrease (p < 0.05) in CFU was observed in the experimental groups in which PDT was performed after applying KI regardless of the concentration of KI. In addition, a significant reduction (p < 0.05) in CFU was observed in the experimental group to which 100 mM KI was applied compared to 10 mM KI. The same results were confirmed when observing CLSM. KI significantly improved the efficacy of erythrosine-mediated PDT on S. mutans biofilms at all concentrations. This may compensate for the low sensitivity of PDT to biofilm-state bacteria strains, but it is necessary to establish an optimal clinical protocol through further research.
4.Evaluation of Acid Resistance of Demineralized Dentin after Silver Diamine Fluoride and Potassium Iodide Treatment
Haesong KIM ; Juhyun LEE ; Siyoung LEE ; Haeni KIM ; Howon PARK
Journal of Korean Academy of Pediatric Dentistry 2022;49(4):392-401
This study investigated the effects of silver diamine fluoride (SDF) and potassium iodide (KI) treatments on the acid resistance of dentin exposed to secondary caries. Sixteen bovine dentin specimens with artificially induced caries were assigned to the following four groups: untreated negative control, untreated positive control, SDF-treated (SDF), and SDF and KI-treated (SDFKI). Multispecies cariogenic biofilms containing Streptococcus mutans, Lactobacillus casei, and Candida albicans were cultured on the specimens for 28 days, except for the negative control group. Specimens from the negative control group were stored in phosphate-buffered saline for that period. After a cariogenic biofilm challenge, the degree of demineralization was evaluated using micro-computed tomography (micro-CT). As a result of data analysis using micro-CT, the demineralization depths of the negative control, positive control, SDF, and SDFKI groups were 149.0 ± 7 μm, 392.0 ± 11 μm, 206.0 ± 20 μm, and 230.0 ± 31 μm, respectively. The degree of demineralization was significantly reduced in the SDF and SDFKI groups compared with that in the untreated positive control group. There were no significant differences between the SDF and SDFKI groups. This study confirmed that SDF and SDFKI treatments increase the acid resistance of dentin to secondary caries. KI did not significantly affect the cariesarresting effect of the SDF.
5.Prevalence of Putative Periodontopahogen TM7 and Dialister in Dental Plaque of Koreans.
International Journal of Oral Biology 2013;38(2):55-59
TM7 is an uncultivated organism which is present in extremely diverse environments. Members of the Dialister genus are difficult to culture as a result of which many of these strains remain uncultivated. It has been suggested that TM7 and Dialister bacteria may belong to a group of suspected periodontal pathogens. In our current study, the presence of the sebacteria in Korean dental plaque samples was assessed using PCR detection methods with specific primers for 16S ribosomal RNA genes. The experimental group included 84 volunteers (35 males and 49 females). Plaque samples were collected from 4 non-adjacent proximal sites of the molar areas of the mandible in each subject and pooled. TM7 was detectable in 56% and the Dialister genus in 27.5% of the volunteers. Both TM7 and Dialister were present in 20.3% of volunteers. We found that 36.9% of the volunteers were negative for both bacteria. Further studies to evaluate the prevalence of these putative pathogenic bacteria in the Korean population are warranted.
Bacteria
;
Dental Plaque
;
Humans
;
Male
;
Mandible
;
Molar
;
Periodontitis
;
Polymerase Chain Reaction
;
Prevalence
;
RNA, Ribosomal, 16S
6.Present and future of hand surgery in Korea.
Mankyung JEON ; Dongchul LEE ; Saehwi KI ; Siyoung ROH ; Jae Won YANG ; Jinsoo KIM
Journal of the Korean Medical Association 2011;54(6):589-593
The purpose of this article is to review the past history of hand surgery briefly and to overview of a vision of hand surgery over next generations in republic of Korea. There were three characteristics of the past history of digit replantation in Korea. Due to the tremendous use of press machine, the replantation surgery for finger amputation had been developed rapidly from 1980's to 1990's period. Also new microsurgery techniques had been introduced such as toe pulp free flap for digit reconstruction. These techniques had been developed based on the medical health insurance system for the factory employees. Future of hand surgery in Korea can be anticipated as followings: operative microscopy and robotics may help surgeons to anastomosis very tiny micro-vessels; the functional recovery of fingers and hands will be more important; incidence of degenerative disease, musculoskeletal system disorder due to excessive use and injury during sports will increase; new materials such as artificial joint will be used more frequently according to the innovation of tissue engineering and regenerative medicine; specialist system for hand surgeon will be settled. Since there are a lot of hand surgeon who has a mission to alleviate patient's pain and injury, there will be a continuous growth of hand surgery in Korea.
Amputation
;
Family Characteristics
;
Fingers
;
Free Tissue Flaps
;
Hand
;
Humans
;
Incidence
;
Insurance, Health
;
Joints
;
Korea
;
Microscopy
;
Microsurgery
;
Missions and Missionaries
;
Musculoskeletal Diseases
;
Replantation
;
Republic of Korea
;
Robotics
;
Specialization
;
Sports
;
Tissue Engineering
;
Toes
;
Vision, Ocular
7.Incidence of Tetracycline Resistance Genes, tet(M) and tet(O), in Streptococci Isolated from Dental Plaques of Koreans.
International Journal of Oral Biology 2014;39(1):9-13
Streptococci are among the normal human microflora that populate the oral cavity. However, oral streptococci are known as a major causative agent for dental caries and bacterial endocarditis. Tetracycline is a broad-spectrum antibiotic that is used for oral infections but two mechanisms of tetracycline resistance in streptococci have been reported. The tet(K) and tet(L) genes in these bacteria are related to the active efflux of tetracycline, whereas tet(M) and tet(O) confer ribosomal protection from this antibiotic. It has been reported that the tetracycline resistance of streptococci is related mainly to the activity of tet(M) and tet(O). In our present study, we examined the prevalence of tet(M) and tet(O) in oral streptococci isolated from Korean dental plaques using PCR. One hundred and forty eight of 635 isolates (23.3%) were tetracycline resistant; 68 of these strains (46%) harbored tet(M) and 3 strains (2%) were positive for tet(O). However, tet(M) and tet(O) did not co-exist in any of the resistant strains. Seventy seven of the 148 tetracycline resistant strains (52%) were negative for both the tet(M) and tet(O) genes.
Bacteria
;
Dental Caries
;
Endocarditis, Bacterial
;
Humans
;
Incidence*
;
Mouth
;
Polymerase Chain Reaction
;
Prevalence
;
Tetracycline
;
Tetracycline Resistance*
8.Incidence of Erythromycin Resistance Genes, erm(B) and mef(A), in Streptococci Isolated from Dental Plaques of Koreans.
International Journal of Oral Biology 2013;38(2):61-65
Erythromycin is a macrolide antibiotic and inhibits bacterial protein synthesis by stimulating the dissociation of the peptidyl-tRNA molecule from the ribosomes during elongation. The use of macrolides has increased dramatically over the last few years and has led to an increase in bacterial resistance to these antibiotics. Bacterial resistance to erythromycin is generally conferred by the ribosome methylation and/or transport (efflux) protein genes. Among the identified erythromycin-resistant genes, erm(B) (erythromycin methylation) and mef(A) (macrolide efflux) are generally detectable in erythromycin-resistant streptococcal species. The distribution of these genes in oral streptococcal isolates has been reported in studies from other countries but has not been previously examined in a Korean study. We here examined by PCR the presence of erm(B) and mef(A) in oral streptococci isolated from Korean dental plaques. Among the 57 erythromycin-resistant strains tested, 64.9% harbored erm(B) whereas 40.4% were positive for mef(A). Eleven isolates had both the erm(B) and mef(A) genes. Twenty six isolates had only erm(B) and 12 isolates had only mef(A). Eight of the 57 strains examined were negative for both genes.
Anti-Bacterial Agents
;
Bacterial Proteins
;
Dissociative Disorders
;
Erythromycin
;
Incidence
;
Macrolides
;
Methylation
;
Polymerase Chain Reaction
;
Ribosomes
;
RNA, Transfer, Amino Acyl
9.Comparison of Three Antibiotic Susceptibility Tests for Viridans Group Streptococci.
International Journal of Oral Biology 2011;36(4):163-166
Oral viridans streptococci are recognized as one of the etiological agents of a variety of infectious diseases such as dental caries and infective endocarditis. Although antimicrobial susceptibility tests for these fastidious bacterial species are now established and standardized, a comparison between the broth microdilution and broth macrodilution tests has not previously been performed. This comparison was performed in the present study using the tests adopted by the Clinical and Laboratory Standards Institute (CLSI) and seven clinical isolates of oral viridans streptococcal strains. A modified broth macrodilution susceptibility test method was also included in this analysis, in which the media was not supplemented with horse blood. The susceptibility interpretation category agreements were measured at 83% (broth microdilution versus broth macrodilution) and 71% (broth microdilution versus modified broth macrodilution). The interpretation category agreement between the broth macrodilution and modified broth macrodilution tests was also 83%. These data indicate that the interpretation of antibiotic susceptibility test results for oral viridans streptococci are influenced by the methods used.
Communicable Diseases
;
Dental Caries
;
Endocarditis
;
Horses
;
Viridans Streptococci
10.Comparison of LIVE/DEAD(R) BacLight(TM) Bacterial Viability Test and alamarBlue(R) Method for Enumeration of Live and Dead Bacteria for Oral Bacterial Species.
International Journal of Oral Biology 2012;37(4):197-201
LIVE/DEAD(R) BacLight(TM) and alamarBlue(R) are fluorescent materials used for the enumeration of live and dead bacteria. LIVE/DEAD(R) BacLight(TM) is generally used for confocal microscopy applications to differentiate live from dead bacteria in a biofilm or planktonic state. AlamarBlue(R) has also been used widely to assay live and dead bacteria in a planktonic state. Whilst these materials are successfully utilized in experiments to discriminate live from dead bacteria for several species of bacteria, the application of these techniques to oral bacteria is limited to the use of LIVE/DEAD(R) BacLight(TM) in biofilm studies. In our present study, we assessed whether these two methods could enumerate live and dead oral bacterial species in a planktonic state. We tested the reagents on Streptococcus mutans, Streptococcus sobrinus, Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans and Enterococcus faecalis and found that only LIVE/DEAD(R) BacLight(TM) could differentiate live from dead cells for all five of these oral strains. AlamarBlue(R) was not effective in this regard for P. gingivalis or A. actinomycetemcomitans. In addition, the differentiation of live and dead bacterial cells by alamarBlue(R) could not be performed for concentrations lower than 2 x 10(6) cells/ml. Our data thus indicate that LIVE/DEAD(R) BacLight(TM) is a more effective reagent for this analysis.
Bacteria
;
Biofilms
;
Enterococcus faecalis
;
Fluorescence
;
Indicators and Reagents
;
Microbial Viability
;
Microscopy, Confocal
;
Oxazines
;
Plankton
;
Porphyromonas gingivalis
;
Streptococcus mutans
;
Streptococcus sobrinus
;
Viridans Streptococci
;
Xanthenes