Anti-Melanogenic Effects of a Polysaccharide Isolated from Undaria pinnatifida Sporophyll Extracts.

Undaria pinnatifida is a temperate brown alga known to exert free radical-scavenging and anti-inflammatory effects. In this study, we investigated the skin-whitening effects of U. pinnatifida sporophyll extracts (UPEs) in α-melanocyte-stimulating hormone (α-MSH)-stimulated B16F10 melanoma cells. The crude polysaccharide fraction (UPF) was obtained via ethanol precipitation. Four polysaccharide fractions (UPF1-4) were isolated and purified using ion-exchange column chromatography, and their anti-melanogenic activity was evaluated. UPF3 exhibited the highest anti-melanogenic activity, showing the highest sulfate (39.79%), fucose (143 µg/mg), and galactose (208 µg/mg) contents. UPF3 significantly inhibited intracellular tyrosinase activity in B16F10 cells. We also evaluated the melanogenic signaling pathway to determine the mechanism of action of UPF3 in melanongenesis. UPF3 reduced the expression of tyrosinase-related protein-1 (TRP-1), tyrosinase-related protein-2 (TRP-2), and tyrosinase, which play important roles in melanin production. Therefore, UPF3 has high potential for use in skin-whitening functional pharmaceuticals and cosmetics.

Skin Improvement Effects of Ultrasound-Enzyme-Treated Collagen Peptide Extracts from Flatfish (Paralichthys olivaceus) Skin in an In Vitro Model.

Collagen is considered to be an intercellular adhesive that prevents tissue stretching or damage. It is widely utilized in cosmetic skin solutions, drug delivery, vitreous substitutions, 3D cell cultures, and surgery. In this study, we report the development of a green technology for manufacturing collagen peptides from flatfish skin using ultrasound and enzymatic treatment and a subsequent assessment on skin functionality. First, flatfish skin was extracted using ultrasound in distilled water (DW) for 6 h at 80 °C. Molecular weight analysis via high-performance liquid chromatography (HPLC) after treatment with industrial enzymes (alcalase, papain, protamex, and flavourzyme) showed that the smallest molecular weight (3.56 kDa) was achieved by adding papain (0.5% for 2 h). To determine functionality based on peptide molecular weight, two fractions of 1100 Da and 468 Da were obtained through separation using Sephadex™ G-10. We evaluated the effects of these peptides on protection against oxidative stress in human keratinocytes (HaCaT) cells, inhibition of MMP-1 expression in human dermal fibroblast (HDF) cells, reduction in melanin content, and the inhibition of tyrosinase enzyme activity in murine melanoma (B16F10) cells. These results demonstrate that the isolated low-molecular-weight peptides exhibit superior skin anti-oxidant, anti-wrinkle, and whitening properties.

How people perceive malicious comments differently: factors influencing the perception of maliciousness in online news comments.

This study proposes a comprehensive model to investigate the factors that influence the perceived maliciousness of online news comments. The study specifically examines individual factors, including demographic characteristics (e.g., gender and age), personality traits (e.g., empathy and attitudes toward online news comments), and reading-related factors (e.g., the amount of news comment reading). Contextual factors such as issue involvement, perceived peer behavior, and the presence of malicious comments in news articles are also considered. The results suggest that most of the proposed variables have a significant impact on the perceived maliciousness of online news comments, except for morality and issue involvement. The findings have important theoretical implications for research on malicious online news comments and provide practical guidelines for online news platforms on how to reduce malicious comments by visualizing them alongside other news comments.

Underestimation of smoking hazards and smoking cessation intervention efficiency among healthcare professionals: A cross-sectional study among Korean occupational health nurses.

INTRODUCTION: Occupational health nurses (OHNs) in South Korea who visit the workplace periodically could play a key role in smoking cessation. It would be helpful to assess their understanding of smoking hazards and smoking cessation methods to encourage them to provide smoking intervention services at the workplace. This study aimed to investigate the knowledge of smoking hazards and perceptions of smoking cessation methods among OHNs. METHODS: We conducted an anonymous self-administered cross-sectional questionnaire survey of 108 OHN nurses employed in an occupational health service outsourcing specialized agency with 19 regional branches in Korea from July to August 2019. We assessed the perceptions of the OHNs about smoking interventions, hazards of smoking, and perceived competence to counsel smokers according to training experience, using chi-squared tests and Fisher's exact tests. RESULTS: The majority of the nurses underestimated the smoking-attributable fraction for lung cancer (78.7%), chronic obstructive pulmonary disease (64.8%), and mortality (49.0%), regardless of training experience on smoking cessation, while more than half perceived their skill and knowledge to counsel patients concerning smoking as inadequate (56.5%). However, those trained in smoking cessation interventions felt more competent in smoking cessation counselling, with 52.2% and 29.3% in the trained and non-trained groups, respectively (p=0.019). CONCLUSIONS: The OHNs in this study underestimated smoking hazards and perceived themselves as lacking counselling skills regarding smoking cessation interventions. It is necessary to encourage OHNs to promote smoking cessation by increasing their knowledge, skills and competence in smoking cessation interventions.

Evaluation of anatomical and histological characteristics of human peripheral nerves: as an effort to develop an efficient allogeneic nerve graft.

Management of peripheral nerve defects is a complicated problem in clinical contexts. Autologous nerve grafting, a gold standard for surgical treatment, has been well known to have several limitations, such as donor site morbidity, a limited amount of available donor tissue, and size mismatches. Acellular nerve allografts (ANAs) have been developed as an alternative and have been applied clinically with favorable outcomes. However, because of the limited availability of commercialized ANAs due to supplier-related issues and high costs, efforts continue to produce alternative sources for ANAs. The present study evaluated the anatomical and histological characteristics of human peripheral nerves using 25 donated human cadavers. The length, diameter, and branching points of various peripheral nerves (median, ulnar, tibial, lateral femoral cutaneous, saphenous, and sural nerves) in both the upper and lower extremities were evaluated. The cross-sectional area (CSA), ratio of fascicular area, and numbers of fascicles were also evaluated via histologic analysis. CSA, the ratio of fascicular area, and the number of fascicles were analyzed statistically in correlation with demographic data (age, sex, height, weight, BMI). The mean length of all evaluated nerves ranged from 17.1 to 41.4 cm, and the mean diameter of all evaluated nerves ranged from 1.2 to 4.9 mm. Multiple regression analysis revealed correlations between the ratio of fascicular area and sex (p = 0.005) and BMI (p = 0.024) (R2 = 0.051). The results of the present study will be helpful in selecting necessary nerve allograft sources while considering the characteristics of each nerve in the upper and lower extremities during ANAs production.

Oral health status and behavior in elderly Koreans with periodontal disease.

OBJECTIVE: The purpose of this study was to investigate oral health status and oral health behaviors in elderly Koreans with periodontal disease. METHODS: The data of the Seventh Korea National Health and Nutrition Examination Survey (2016-2018) were used. This cross-sectional study included 2981 individuals who were at least 65 years of age. Periodontal disease was assessed in oral health exams. Subjective oral health status (e.g., toothache) and oral health behaviors (e.g., tooth brushing and oral health examination) were assessed in health interviews. Data were analyzed using descriptive statistics, chi-square tests, and logistic regression. RESULTS: The overall prevalence of periodontal disease in the study population was 47.5%. Individuals with periodontal disease were more likely to have a toothache than those without periodontal disease (adjusted odds ratio [aOR] = 1.46, 95% confidence interval [CI] = 1.20-1.77). Individuals with periodontal disease were also more likely to have chewing discomfort (aOR = 1.21, 95% CI = 1.01-1.44) and less likely to use oral hygiene products (aOR = 0.74, 95% CI = 0.60-0.91) than those without periodontal disease. CONCLUSIONS: About half of elderly had the periodontal disease. Elderly Koreans with periodontal disease were more likely to have poor oral health and behavior than those without periodontal disease. The results of this study provide an insight into social and behavioral factors associated with periodontal diseases in older Koreans. It is necessary to confirm these results through prospective studies.

Occupational health nurses' personal attitudes toward smoking: A cross-sectional study.

OBJECTIVES: This study aims to investigate if experience in smoking intervention training influences attitudes toward smoking, discuss the role of health management programs of small- and medium-sized enterprises, and analyze the current attitude of occupational health nurses regarding the hazards of smoking and responsibility to smokers to effectively facilitate smoking cessation support programs. METHODS: We conducted an anonymous self-administered cross-sectional survey of 108 nurses employed in occupational health services outsourcing specialized agency in Korea. We assessed the difference in attitude about smoking according to training experience in smoking interventions and perceived competence in counseling smokers using chi-square test and Fisher's exact test. RESULTS: Occupational health nurses with the training experience of smoking interventions tend to perceive the harmful effects of smoking more seriously, compared to occupational health nurses without the training experience (P = .024, Fisher's exact test) and the OHSO nurses with the training experience tend to have professional ethics as health care professionals (P = .017, Fisher's exact test). Occupational health nurses having expertise in smoking cessation counseling tended to have professional ethics (P = .047, Fisher's exact test) and social responsibility as health care professionals (P = .022, Fisher's exact test). CONCLUSION: The occupational health nurses with training experience and expertise in smoking cessation counseling perceive the harmful effects of smoking more strongly and can enhance their professional ethics and social responsibility as health care professionals.

Combinatorial Effects of Protective Agents on Survival Rate of the Yeast Starter, Saccharomyces cerevisiae 88-4, after Freeze-Drying.

A yeast starter is formulated for commercial practices, including storage and distribution. The cell viability of the yeast starter is one of the most important factors for manufacturing alcoholic beverages to ensure their properties during the fermentation and formulation processes. In this study, 64 potential protective agents were evaluated to enhance the survival rate of the brewing yeast Saccharomyces cerevisiae 88-4 after freeze-drying. In addition, the optimized combination of protective agents was assessed for long-term storage. Finally, response surface methodology was applied to investigate the optimal concentration of each protectant. Twenty of the 64 additives led to an increase in the survival rate of freeze-dried S. cerevisiae 88-4. Among the various combinations of protectants, four had a survival rate >95%. The combination of skim milk, maltose, and maltitol exhibited the best survival rate of 61% after 42 weeks in refrigerated storage, and the composition of protectants optimized by response surface methodology was 6.5-10% skim milk, 1.8-4.5% maltose, and 16.5-18.2% maltitol. These results demonstrated that the combination of multiple protectants could alleviate damage to yeasts during freeze-drying and could be applied to the manufacturing starters for fermented foods.

AP2M1 Supports TGF-ß Signals to Promote Collagen Expression by Inhibiting Caveolin Expression.

The extracellular matrix (ECM) is important for normal development and disease states, including inflammation and fibrosis. To understand the complex regulation of ECM, we performed a suppressor screening using Caenorhabditis elegans expressing the mutant ROL-6 collagen protein. One cuticle mutant has a mutation in dpy-23 that encodes the µ2 adaptin (AP2M1) of clathrin-associated protein complex II (AP-2). The subsequent suppressor screening for dpy-23 revealed the lon-2 mutation. LON-2 functions to regulate body size through negative regulation of the tumor growth factor-beta (TGF-ß) signaling pathway responsible for ECM production. RNA-seq analysis showed a dominant change in the expression of collagen genes and cuticle components. We noted an increase in the cav-1 gene encoding caveolin-1, which functions in clathrin-independent endocytosis. By knockdown of cav-1, the reduced TGF-ß signal was significantly restored in the dpy-23 mutant. In conclusion, the dpy-23 mutation upregulated cav-1 expression in the hypodermis, and increased CAV-1 resulted in a decrease of TßRI. Finally, the reduction of collagen expression including rol-6 by the reduced TGF-ß signal influenced the cuticle formation of the dpy-23 mutant. These findings could help us to understand the complex process of ECM regulation in organism development and disease conditions.

Corrigendum to: Deceased donor liver transplantation under the Korean model for end-stage liver disease score-based liver allocation system: 2-year allocation results at a high-volume transplantation center.

[This corrects the article on p. 112 in vol. 33.].

An analysis of the number of liver and kidney transplantations during COVID-19 pandemic in Korea.

Background: The severity of the coronavirus disease 2019 (COVID-19) pandemic has discouraged organ donation. However, the prevalence of COVID-19 in Korea was much lower in comparison to Western countries. With this, the authors decided to determine the real-world impact of COVID-19 on organ donation and transplantation in Korea. Methods: The number of kidney transplantations (KTs) and liver transplantations (LTs) performed in 2020 were compared with those in 2019 using the Korean Network for Organ Sharing database and Asan Medical Center (AMC) database. Results: The annual number of deceased donors (DDs) was 450 in 2019 compared to 478 in 2020. Monthly DD number was 37.5±5.9 in 2019 and 39.8±4.4 in 2020 (P=0.284). Annual number of DD kidney transplant (DDKT) was 794 in 2019 and 848 in 2020, and monthly number was 66.1±10.4 in 2019 and 70.7±9.8 in 2020 (P=0.285). The annual number of DDLT was 391 in 2019 and 395 in 2020, and the monthly number was 32.6±5.7, 2019 and 32.9±4.7 in 2020 (P=0.877). The annual number of living donor (LD) KT was 2,293 in 2019 and 1,432 in 2020, and the monthly number was 191.1±19.5 in 2019 and 119.3±11.7 in 2020 (P<0.001). Annual number of living donor LDLT was 1,577 in 2019 and 1,146 in 2020, and monthly number was 131.4±18.1 in 2019 and 95.5±8.0 in 2020 (P<0.001). In the AMC, not all types of KT and LT changed significantly. Conclusions: The results of this study indicate that the number of DD organ transplantations remained stable in Korea in 2020, but the number of LD organ transplantations was significantly reduced. However, the number of organ transplantations did not change in the AMC.

Rab8 and Rabin8-Mediated Tumor Formation by Hyperactivated EGFR Signaling via FGFR Signaling.

The epidermal growth factor receptor (EGFR) signaling is important for normal development, such as vulval development in Caenorhabditis elegans, and hyperactivation of the EGFR is often associated with cancer development. Our previous report demonstrated the multivulva (Muv) phenotype, a tumor model in C. elegans (jgIs25 strain) by engineering LET-23/EGFR with a TKI-resistant human EGFR T790-L858 mutant. Because Rab proteins regulate vesicle transport, which is important for receptor signaling, we screened the RNAi in the jgIs25 strain to find the Rabs critical for Muv formation. Herein, we show that rab-8 RNAi and the rab-8 (-/-) mutation effectively reduce Muv formation. We demonstrate that RABN-8, an ortholog of Rabin8, known as a GEF for Rab8, is also required for Muv formation by promoting the secretion of EGL-17/FGF from vulval precursor cells. In addition, FGFR inhibitors decreased Muv formation mediated by mutant EGFR. Our data suggest that Rab8 and Rabin8 mediate Muv formation through FGF secretion in the EGFR-TKI-resistant nematode model. Furthermore, FGFR-TKIs more effectively inhibit the growth of lung cancer cell lines in H1975 (EGFR T790M-L858R; EGFR-TKI-resistant) than H522 (wild-type EGFR) and H1650 (EGFR exon 19 deletion; EGFR-TKI-sensitive) cells, suggesting that FGFR-TKIs could be used to control cancers with EGFR-TKI-resistant mutations.

Gastric and rectal cancers in workers exposed to asbestos: a case series.

BACKGROUND: The Occupational Safety and Health Research Institute (OSHRI) of the Korea had not recognized gastrointestinal cancer as work-related disease during their evaluation. However, in 2018 OSHRI recognized gastric and rectal cancers as work-related disease in asbestos-exposed workers. We present 2 such cases along supportive evidence of causation. CASE PRESENTATION: Patient A: A 57-year-old man had worked for about 40 years since 1978 as an oxygen cutter at workplaces that dismantle ships, buildings, boilers, and thermal power plants. In November 2016, endoscopy and biopsy confirmed the diagnosis of advanced gastric cancer, for which he underwent subtotal gastrectomy and chemotherapy; however, he later died of the cancer. Patient B: A 71-year-old man had worked in shipbuilding and repair workplaces for approximately 49 years, being employed in pipe laying, asbestos insulation installation, grinding, and other ship repair work. In 2003, he was diagnosed of rectal cancer by abdominal computed tomography. He accordingly underwent surgical removal of the cancer. Based on the occupational history of the 2 patients and our review of the relevant literature addressing the occupational environment, we concluded that both patients had continuous exposure to high levels of asbestos while performing their jobs for 40 and 49 years, respectively. CONCLUSION: Both patients had a history of smoking and drinking (non-occupational personal risk factors). However, the possibility of an increased risk of gastric and rectal cancers from asbestos exposure cannot be excluded. Therefore, we considered that occupational exposure to asbestos had contributed to the cancer diagnosis in these cases. Workers exposed to asbestos should be made aware of the possibility of gastric or rectal cancer, and should undergo monitoring and medical examinations. Appropriate compensation for gastric and rectal cancers that occur in workers exposed to asbestos are anticipated in future.

Electronic Cigarette Themes on Twitter: Dissemination Patterns and Relations with Online News and Search Engine Queries in South Korea.

This study examines multiple aspects of e-cigarette mentions on different online media channels during the announcement and implementation of a cigarette tax increase policy in South Korea. It consists of three parts. First, a Naive Bayes classifier was used to sort 59,147 tweets about e-cigarettes into five pre-designated themes - promotion, health, policy, product evaluation, and price - and to determine their relative prevalence. Second, social network analysis was used to identify the themes' dissemination patterns. Third, the themes were examined for their associations with e-cigarette mentions in two other media channels - online news articles (n = 580) and search engine queries (64 weeks of Google Trends data). Results show that the most prevalent tweet theme was product evaluation, and the theme with the largest increase during the data collection period was promotion. Promotion-themed tweets were the least connected with tweets about the other five themes, while health-themed tweets were the most connected. Finally, product evaluation-themed tweets exhibited the strongest correlation with search engine query count and had the largest explanatory power.

CCR5-mediated Recruitment of NK Cells to the Kidney Is a Critical Step for Host Defense to Systemic Candida albicans Infection.

C-C chemokine receptor type 5 (CCR5) regulates the trafficking of various immune cells to sites of infection. In this study, we showed that expression of CCR5 and its ligands was rapidly increased in the kidney after systemic Candida albicans infection, and infected CCR5-/- mice exhibited increased mortality and morbidity, indicating that CCR5 contributes to an effective defense mechanism against systemic C. albicans infection. The susceptibility of CCR5-/- mice to C. albicans infection was due to impaired fungal clearance, which in turn resulted in exacerbated renal inflammation and damage. CCR5-mediated recruitment of NK cells to the kidney in response to C. albicans infection was necessary for the anti-microbial activity of neutrophils, the main fungicidal effector cells. Mechanistically, C. albicans induced expression of IL-23 by CD11c+ dendritic cells (DCs). IL-23 in turn augmented the fungicidal activity of neutrophils through GM-CSF production by NK cells. As GM-CSF potentiated production of IL-23 in response to C. albicans, a positive feedback loop formed between NK cells and DCs seemed to function as an amplification point for host defense. Taken together, our results suggest that CCR5-mediated recruitment of NK cells to the site of fungal infection is an important step that underlies innate resistance to systemic C. albicans infection.

Comparison of the regeneration induced by acellular nerve allografts processed with or without chondroitinase in a rat model.

There have been various studies about the acellular nerve allograft (ANA) as the alternative of autologous nerve graft in the treatment of peripheral nerve defects. As well as the decellularization process methods of ANA, the various enhancement methods of regeneration of the grafted ANA were investigated. The chondroitin sulfate proteoglycans (CSPGs) inhibit the action of laminin which is important for nerve regeneration in the extracellular matrix of nerve. Chondroitinase ABC (ChABC) has been reported that it enhances the nerve regeneration by degradation of CSPGs. The present study compared the regeneration of ANA between the processed without ChABC group and the processed with ChABC group in a rat sciatic nerve 15 mm gap model. At 12 weeks postoperatively, there was not a significant difference in the histomorphometric analysis. In the functional analysis, there were no significant differences in maximum isometric tetanic force, wet muscle weight of tibialis anterior. The processed without ChABC group had better result in ankle contracture angle significantly. In conclusion, there were no significant differences in the regeneration of ANA between the processed without ChABC group and the processed with ChABC group.

Deceased donor liver transplantation under the Korean model for end-stage liver disease score-based liver allocation system: 2-year allocation results at a high-volume transplantation center.

Background: The Korean model for end-stage liver disease (MELD) score-based liver allocation system was started in June 2016 in Korea. Methods: This study analyzed the detailed allocation results of deceased donor liver transplantation (DDLT) during the first 2 years after the MELD score-based liver allocation system implementation at a high-volume liver transplantation (LT) center in Korea. Results: This study included 174 patients with age above 12 years. The patient ABO blood groups were A (n=65, 37.4%), B (n=51, 29.3%), O (n=28, 16.1%), and AB (n=30, 17.2%). The LT types were primary LT in 141 patients (81.0%) and retransplantation in 33 (19.0%). The Korean Network for Organ Sharing status categories at LT were as follows: status 1 (n=11, 6.3%), status 2 (n=82, 47.1%), status 3 (n=63, 36.2%), and status 4 (n=18, 10.3%). The mean MELD score at LT and waiting period were 36.6±4.6 and 62.1±98.2 days in blood group A; 37.6±3.6 and 25.7±38.1 days in blood group B; 38.8±2.7 and 26.0±30.5 days in blood group O; and 34.8±5.5 and 68.4±110.5 days in blood group AB (P<0.001 and P=0.012), respectively. Patients with blood group O and AB had the highest and lowest mean MELD scores at LT allocation, respectively. Conclusions: Serious deceased organ donor shortage resulted in very high MELD score cutoffs for DDLT allocation. Additionally, a significant inequality was observed in the possibility for DDLT according to blood group compatibility. Nationwide follow-up studies are necessary to precisely determine the allocation status of DDLT.

Effects of an Online Imagery-Based Treatment Program in Patients with Workplace-Related Posttraumatic Stress Disorder: A Pilot Study.

OBJECTIVE: We developed easily accessible imagery-based treatment program for patients with post-traumatic stress disorder (PTSD) related to workplace accidents and investigated the effects of the program on various PTSD related symptoms. METHODS: The program was based on an online platform and consisted of eight 15-min sessions that included script-guided imagery and supportive music. Thirty-five patients with workplace-related PTSD participated in this program 4 days per week for 4 weeks. Its effects were examined using self-report questionnaires before and after the take-home online treatment sessions. RESULTS: After completing the 4-week treatment program, patients showed significant improvements in depressed mood (t=3.642, p=0.001) based on the Patient Health Questionnaire-9 (PHQ-9), anxiety (t=3.198, p=0.003) based on the Generalized Anxiety Disorder seven-item (GAD-7) scale, and PTSD symptoms (t=5.363, p<0.001) based on the Posttraumatic Stress Disorder Check List (PCL). In particular, patients with adverse childhood experiences exhibited a greater degree of relief related to anxiety and PTSD symptoms than those without adverse childhood experiences. CONCLUSION: The present. RESULTS: demonstrated that the relatively short online imagery-based treatment program developed for this study had beneficial effects for patients with workplace-related PTSD.

Impaired Executive Functioning of Sexual Assault Survivors with Acute Stress Disorder.

This study aimed to examine the executive functioning of survivors exposed to recent sexual assaults. Twenty-seven female rape survivors who met the criterion for acute stress disorder (ASD) were enrolled and completed the assessment within 4 weeks after the traumatic experience. Additionally, 25 age-matched female health controls (HC) never exposed to such a traumatic event were enrolled. The assessments evaluated psychiatric symptoms including post-traumatic stress symptoms, depression, anxiety, and trait and state anger; general intelligence indexed by intellectual quotient (IQ); and executive functioning including set-shift/attention, planning, spatial working memory, and inhibition using the Cambridge Neuropsychological Test Automated Battery. The ASD group showed higher levels of depression, anxiety, and state anger, and lower IQ than the HC group. The ASD group also showed global impairment of executive functioning for set-shifting, attention, planning, and response inhibition compared to the HC group. Rather than being associated with low IQ and education levels, these results could be from trauma-related effects in survivors with ASD. Additionally, the state anger level was related to survivors' deficient executive functioning. The findings indicate the importance of providing assessment and intervention efforts to sexual assault survivors soon after the trauma occurs.

DNA-Functionalized 100 nm Polymer Nanoparticles from Block Copolymer Micelles.

DNA-mediated self-assembly of colloidal particles is one of the most promising approaches for constructing colloidal superstructures. For nanophotonic materials and devices, DNA-functionalized colloids with diameters of around 100 nm are essential building blocks. Here, we demonstrate a strategy for synthesizing DNA-functionalized polymer nanoparticles (DNA-polyNPs) in the size range of 55-150 nm using block copolymer micelles as a template. Diblock copolymers of polystyrene- b-poly(ethylene oxide) with an azide end group (PS- b-PEO-N3) are first formed into spherical micelles. Then, the micelle cores are swollen with the styrene monomer and polymerized, thus producing PS NPs with PEO brushes and azide functional end groups. DNA strands are conjugated onto the ends of the PEO brushes through a strain-promoted alkyne-azide cycloaddition reaction, resulting in a DNA density of more than one DNA strand per 12.6 nm2 for 70 nm particles. The DNA-polyNPs with complementary sequences enable the formation of CsCl-type colloidal superstructure by DNA binding.