Effects of rhBMP-2 with various carriers on maxillofacial bone regeneration through computed tomography evaluation.

BACKGROUND: rhBMP-2 is regarded as the most potent osteoinductive growth factor, and it has been used in the oral cavity with different carriers. The purpose of this study is to evaluate the bone-regenerative effect of rhBMP-2 delivered with different carrier systems through three-dimensional cone beam computed tomography analysis. METHOD: A total of 112 patients underwent oral surgery with rhBMP-2 application (Group 1, n = 53) or without rhBMP-2 application (Group 2, n = 59). Group 1 was divided into 3 groups according to carriers, rhBMP-2 with allograft (Group 1-1, n = 34), rhBMP-2 with xenograft (Group 1-2, n = 5), and rhBMP-2 with absorbable collagen sponge (Group 1-3, n = 14). Cone beam computed tomography scans were taken before surgery (T0) 6 months after surgery (T1). The volume of defects was measured through the three-dimensional image analysis tool. RESULTS: The average bone regeneration rate of Group 1 was significantly greater than that of Group 2. Within Group 1, the group that used allograft as a carrier (Group 1-1) showed significantly higher bone regeneration rates than the group that used absorbable collagen sponge as a carrier (Group 1-3). CONCLUSION: The use of rhBMP-2 after oral surgery results in a superior bone regeneration rate compared to not using rhBMP-2, and its efficacy depends on the carriers it is used with. Allograft affects bone regeneration more than absorbable collagen sponge when it is carried with rhBMP-2. Therefore, the appropriate use of rhBMP-2 with suitable bone grafting materials is useful for promoting postoperative bone regeneration in oral surgery.

Why is Success of South Korea's Covid-19 Response Fading?

South Korea demonstrated its ability to respond effectively with rapid policy measures and implementation in the early stages of the pandemic. However, at the end of second year of the pandemic, South Korea reached a peak in its number of daily new cases. Why didn't South Korea maintain the initial successful performance? To answer the question, this study examined South Korea's pandemic response process through Complex Adaptive Systems (CAS), focusing on actors' behavior according to the phase transition. We found that the South Korean government failed to interact with the rapidly evolving public due to the different evolving pace. Dissonance between the government and the public resulted in distrust, fatigue, and resistance to the government's policy among people. From the case study of South Korea, this study emphasizes that not only individual governments, but also the international community, should anticipate and interact with the rapidly evolving public to prepare for the pandemic and post-pandemic era.

Correlation between the Injury Site and Trauma Mechanism in Severely Injured Patients with Blunt Trauma.

Background: In patients with severe injury, predicting the injury site without using advanced diagnostic modalities can help formulate a diagnosis and treatment plan based on the suspected injury site. Objectives: This study aimed to determine the correlation between the injury site and trauma mechanism in severely injured patients with blunt trauma. Methods: We retrospectively analyzed the clinical characteristics-including age, sex, date of emergency room (ER) visit, time of injury, trauma mechanism (car accident, motorcycle accident, bicycle accident, pedestrian accident, fall, slipping and rolling down, crush injury, assault, and others), final diagnosis, injury severity score, abbreviated injury scale (AIS) score, and injury site-of 1,245 patients in a tertiary trauma center. Results: There was a strong correlation between certain injury sites and specific trauma mechanisms. In particular, most trauma mechanisms were associated with injury to the head and neck, as well as the chest, with a combined frequency of >40.0%. Moreover, when using one-way analysis of variance and Bonferroni's post hoc tests, there were significant differences in AIS scores 1, 3, 4, and 5 for each trauma mechanism. Conclusion: Generally, when patients with severe injury present to the ER, the injury site can be predicted upon initial assessment based on the trauma mechanism. Based on our study, the injury site predicted by a specific mechanism should be checked repeatedly and additionally through physical examination and imaging tools. This can reduce misdiagnosis and help with accurate diagnosis and treatment.

Clinical significance of hypoalbuminemia in patients with scrub typhus complicated by acute kidney injury.

BACKGROUND: This study aimed to investigate the clinical significance of hypoalbuminemia (HA) in patients with scrub typhus complicated by acute kidney injury (AKI). METHODS: From 2009 to 2018, 611 patients were diagnosed with scrub typhus. We divided the patients into two groups [normoalbuminemia (NA) vs. HA] based on the serum albumin level of 3.0 g/dL and compared the incidence, clinical characteristics, and severity of AKI based on the RIFLE classification between the two groups. RESULTS: Of the total 611 patients, 78 (12.8%) were categorized into the HA group. Compared to patients in the NA group, patients in the HA group were older (73 ± 9 vs. 62 ± 14 years, P<0.001). The HA group had a significantly longer hospital stay (9.6 ± 6.2 vs 6.2 ± 3.1 days, p<0.001) and a higher incidence of complications in respiratory and cardiovascular systems. Furthermore, AKI developed significantly more in patients in the HA group (58% vs. 18%, p<0.001) as compared to the NA group. The overall incidence of AKI was 23.1%; of which, 14.9%, 7.0%, and 1.2% of cases were classified as Risk, Injury, and Failure, respectively. The serum albumin level correlated with AKI severity (3.4 ± 0.5 vs 3.0 ± 0.5 vs 2.6 ± 0.3, p<0.05). In a multivariate logistic regression analysis for predicting AKI, age, presence of co-morbidities such as chronic kidney disease, total bilirubin, leukocytosis, and hypoalbuminemia were significant predictors for AKI. CONCLUSION: Serum albumin level is helpful to predict the development and severity of scrub typhus-associated AKI.

Urinary Exosomal microRNA-21 as a Marker for Scrub Typhus-Associated Acute Kidney Injury.

Background: Urinary microRNA (miRNA)-21 is a biomarker for acute kidney injury (AKI). We conducted this study to determine if a urinary exosomal analysis for this biomarker could serve as a novel diagnostic approach for detecting kidney disease. Materials and Methods: We investigated the clinical significance of urinary exosomal miRNA-21 levels for AKI in scrub typhus patients. We collected 138 urine samples from scrub typhus patients at the time of admission. Urinary exosomal miRNA-21 was assessed in 25 age- and sex-matched scrub typhus patients with and without AKI. Results: The total leukocyte count was higher in AKI patients than in non-AKI patients (10.40 × 103/mL vs. 6.40 × 103/mL, p < 0.01). Urinary exosomal miRNA-21 levels were higher in the AKI group than in the non-AKI group (20.1 ± 1.2 vs. 17.8 ± 1.8 ΔCt value of miRNA-21, p < 0.01). Additionally, the miRNA-21 levels correlated directly with the total leukocyte counts and inversely with the estimated glomerular filtration rate. A receiver operating characteristic curve analysis demonstrated good discriminative power for the diagnosis of scrub typhus-associated AKI, with an area under the curve value of 0.907. Conclusion: Urinary exosomal miRNA-21 could be a surrogate marker for scrub typhus-associated AKI diagnosis.

Double Negative Differential Resistance Device Based on Hafnium Disulfide/Pentacene Hybrid Structure.

Recently, combinations of 2D van der Waals (2D vdW) materials and organic materials have attracted attention because they facilitate the formation of various heterojunctions with excellent interface quality owing to the absence of dangling bonds on their surface. In this work, a double negative differential resistance (D-NDR) characteristic of a hybrid 2D vdW/organic tunneling device consisting of a hafnium disulfide/pentacene heterojunction and a 3D pentacene resistor is reported. This D-NDR phenomenon is achieved by precisely controlling an NDR peak voltage with the pentacene resistor and then integrating two distinct NDR devices in parallel. Then, the operation of a controllable-gain amplifier configured with the D-NDR device and an n-channel transistor is demonstrated using the Cadence Spectre simulation platform. The proposed D-NDR device technology based on a hybrid 2D vdW/organic heterostructure provides a scientific foundation for various circuit applications that require the NDR phenomenon.

Transplantation of a kidney from a donor with vancomycin-resistant Enterococci.

The colonization of vancomycin-resistant Enterococci before and after solid organ transplantation is associated with an increased risk of its infection. The prevalence of these bacterial colonies in renal transplant recipients are as high as that in intensive care unit patients. However, it is unclear whether donors with vancomycin-resistant Enterococci colonization can be considered in renal transplantation. Herein, we report a case wherein a kidney was transplanted from a deceased donor with vancomycin-resistant Enterococci colonies in urine and rectal swab. After transplant, the recipient had no vancomycin-resistant Enterococci infection and maintained relatively good renal function.

Association between Hospital Nurses' Perception of Patient Safety Management and Standard Precaution Adherence: A Cross-Sectional Study.

Standard precautions should be applied to prevent health care-associated infections during every nursing activity. However, adherence to standard precautions was reported to be inadequate. Therefore, this study aimed to identify the rates of standard precaution adherence and the association between perception of patient safety management and standard precaution adherence. In this cross-sectional descriptive study, a convenience sample of nurses was recruited from a university-affiliated teaching hospital in Seoul, Korea. Data were collected using a structured self-report questionnaire. Among the 332 questionnaires returned (response rate: 94.9%), a total of 329 nurses were analyzed. In the present study, the overall standard precaution adherence rate was approximately 53.5%. The multiple linear regression results revealed that participants' perceptions of patient safety management were only significantly associated with standard precaution adherence after adjusting other covariates (ß = 0.412, p < 0.001). Nurse supervisors should focus more on raising awareness about nurses' perception of patient safety management based on the specific work environment, such as the total number of nurses working together and the nurse-to-patient ratio. Nurse educators should develop integrated curricula to help graduate nurses transition smoothly into professional practice and enhance adherence to standard precautions in diverse health care settings.

Polarity control in a single transition metal dichalcogenide (TMD) transistor for homogeneous complementary logic circuits.

Recently, there have been various attempts to demonstrate the feasibility of transition metal dichalcogenide (TMD) transistors for digital logic circuits. A complementary inverter circuit, which is a basic building block of a logic circuit, was implemented in earlier works by heterogeneously integrating n- and p-channel transistors fabricated on different TMD materials. Subsequently, to simplify the circuit design and fabrication process, complementary inverters were constructed on single-TMD materials using ambipolar transistors. However, continuous transition from the electron-conduction to the hole-conduction state in the ambipolar devices led to the problem of a high leakage current. Here, we report a polarity-controllable TMD transistor that can operate as both an n- and a p-channel transistor with a low leakage current of a few picoamperes. The device polarity can be switched simply by converting the sign of the drain voltage. This is because a metal-like tungsten ditelluride (WTe2) with a low carrier concentration is used as a drain contact, which subsequently allows selective carrier injection at the palladium/tungsten diselenide (WSe2) junction. In addition, by using the operating principle of the polarity-controllable transistor, we demonstrate a complementary inverter circuit on a single TMD channel material (WSe2), which exhibits a very low static power consumption of a few hundred picowatts. Finally, we confirm the expandability of this polarity-controllable transistor toward more complex logic circuits by presenting the proper operation of a three-stage ring oscillator.

Regional Differences of Mental Health Status and Associated Factors: Based on the Community Health Survey.

OBJECTIVES: The aim of this study was to determine whether there were differences in mental health specific to regions in Korea, and the factors that affected mental health status. METHODS: Data from the 2016 Community Health Survey in Korea were used; 224,421 health survey participants provided responses on mental health issues, demographics, and health behavior, and were included in the study. RESULTS: A statistically significant difference was observed in the incidence of mental health status between different regions of Korea. Independent variables that affected mental health were sex, age, marital status, household income, economic activity, whether living with dementia patients, self-reported health status, smoking, alcohol drinking, sleep time, and chronic diseases. Risk factors associated with symptoms of depression were gender (female), bereavement or being divorced, low household income, family member with dementia, poor self-reported health status, currently smoking, level of physical activity, insufficient hours of sleep and suffering from chronic diseases. CONCLUSION: This study suggests that a standardized healthcare policy is needed to reduce regional variation in mental health. In the future, similar studies that include medical expenses for mental healthcare and relevant variables according to regions of Korea should be conducted.

Regional Disparity and Factors Influencing Unmet Medical Needs: A Study Based on the Sixth Korea National Health and Nutrition Examination Survey (2015).

OBJECTIVES: This study aimed to determine regional differences and the factors that affect unmet medical needs. METHODS: Data from the 6th Korea National Health and Nutrition Examination Survey (2015) were used, and 4,946 health survey participants who provided responses on medical utilization and health behavior were included in the study. RESULTS: A statistically significant difference was observed in the incidence rate of unmet medical needs in terms of region. The independent variables that affected unmet medical needs were sex, age, education, region, household income, insurance type, smoking status, self-reported health status, and stress awareness. Gender (female), lower education level, rural residents, lowest household income, poor self-reported health status, and stress awareness increased the probability of unmet medical needs. CONCLUSION: Our findings suggested that different policies and approaches should be considered for each population that is at risk to address the primary cause of the unmet medical needs. Further studies that include medical expenses and the relevant variables of an area should be conducted in the future.

Analysis of variation in length of stay (LOS) after ischemic and hemorrhagic stroke using the Charlson Comorbidity Index (CCI).

[Purpose] The purpose of this study was to understand factors present at baseline that affect outcome and healthcare utilization post-stroke. We investigated the association between the Charlson Comorbidity Index (CCI) score and functional outcome (length of stay) after hemorrhagic and ischemic stroke. [Subjects and Methods] Data from the Korean National Hospital Discharge In-depth Injury Survey for 6 years, from 2005 to 2010, were used. The t-test and analysis of variance were carried out to compare average differences in the length of stay with the general characteristics in accordance with CCI. Multiple regression analysis was carried out using dummy variables to look at factors affecting stroke patients' length of stay. [Results] Independent variables with significant relationships with the log-transformed length of stay included gender, type of insurance, the size of city of residence, the number of beds in the hospital, the location of the medical institution, hospitalization path, receipt of physical therapy, treatment involving brain surgery, death, the type of stroke, and CCI. [Conclusion] The results of the present study suggests that CCI independently influences the length of stay after ischemic and hemorrhagic stroke and that variables with significant relationships with the log-transformed length of stay need to be continuously managed.

Association of the UCP-1 single nucleotide polymorphism A-3826G with the dampness-phlegm pattern among Korean stroke patients.

BACKGROUND: Patients with stroke have various syndromes and symptoms. Through pattern identification (PI), traditional Korean medicine (TKM) classifies the several syndromes and symptoms of stroke patients into five categories: Fire-heat (FH), Dampness-phlegm (DP), Yin-deficiency (YD), Qi-deficiency (QD) and Blood-stasis (BS). DP has been associated with obesity and hyperlipidemia. Uncoupling protein-1 (UCP-1), which plays a major role in thermogenesis and energy expenditure can increase the risk of obesity and can be related metabolic disorders. In this study, we elucidated the association of three polymorphisms located in the UCP-1 promoter and coding region with DP among Korean stroke patients. METHODS: 1,593 patients with cerebral infarction (583/DP, 1,010/non-DP) and 587 normal subjects were enrolled. The genotypes A-3826G, G-1766A and Ala64Thr (G+1068A) for each subject were determined by polymerase chain reaction with TaqMan probes and five percent of subjects were re-genotyped by sequencing method to confirm the accuracy of genotyping. The results were analyzed using a multiple logistic regression model to evaluate the genetic associations: the UCP-1polymorphisms of normal versus those of DP subjects and those of normal versus those of non-DP subjects. RESULTS: A significantly higher percentage of subjects in the DP group possessed the A-3826G G allele than the A allele (OR=1.508, p=0.006). Furthermore, the number of subjects with the GG type of A-1766G was significantly lower in the non-DP group than the normal group in the recessive model (OR=0.606, p=0.042). In addition, an analysis of the relationship among 2 SNPs of UCP-1 and lipid serum concentration showed that the serum level of HDL cholesterol was significantly higher in subjects with the A-3826G G allele in the normal group (p=0.032). Serum triglyceride and HDL cholesterol were also associated with the A-1766G variant in the recessive model (p=0.002, p=0.046). CONCLUSIONS: These results suggest that that the A-3826G and A-1766G UCP-1 polymorphisms, which are related to obesity, might be candidate genetic markers for the DP pattern in the TKM diagnosis system.

Differential Association of Uncoupling Protein 2 Polymorphisms with Pattern Identification among Korean Stroke Patients: A Diagnostic System in Traditional Korean Medicine.

Uncoupling protein 2 (UCP2), a mitochondrial protein present in many organs and cell types, is known to dissipate the proton gradient formed by the electron transport chain. Its function is correlated with predictive parameters, such as obesity, diabetes, and metabolic syndromes. We analyzed the distribution of UCP2 polymorphisms in stroke patients diagnosed with one of the following four stroke subtypes based on the TKM standard pattern identification (PI): Qi-deficiency (QD), Dampness and Phlegm (D&P), Yin-deficiency (YD), and Fire and Heat (F&D). We studied a total of 1,786 stroke patients (397/QD, 645/D&P, 223/YD, and 522/F&D, 586/normal). Genotyping for the G-1957A, G-866A and A55V UCP2 polymorphisms was performed using the TaqMan. G-866A and A55V were significantly associated with the D&P and H&F subtypes. The frequency of subjects with the A allele of G-866A was significantly lower than the frequency of subjects with the GG type. The A55V polymorphism was also shown similar effect with G-866A in the dominant model. In contrast, no SNPs were shown to be associated with the QD or YD subtypes in this study. These results showed that the G-866A and A55V UCP2 polymorphisms may be genetic factors for specific PI types among Korean stroke patients.

WNT10B Polymorphism in Korean Stroke Patients with Yin Deficiency Pattern.

WNT10B has been indicated as a potential regulator of adipogenesis in vivo and in vitro models of obesity. In this study, we analyzed the distribution of WNT10B polymorphism in elderly Korean subjects with cerebral infarction (CI) and Yin Deficiency pattern and Non-Yin Deficiency pattern. A total of 630 CI patients, including 75 with Yin Deficiency pattern and 555 with Non-Yin Deficiency pattern, participated in this study. SNP (G-607C) genotyping was conducted by primer extension using TaqMan probe; five percent of subjects were regenotyped by direct sequencing to confirm the accuracy of the genotyping. The results were analyzed using a multiple logistic regression model to evaluate the genetic association between the G-607C variant and Yin Deficiency pattern. The frequency of the CC genotype of G-607C in the Yin Deficiency pattern group (29.33%) was significantly higher than that in the Non-Yin Deficiency pattern group (23.96%) (P = 0.0339 , OR = 2.005 (1.054-3.814)) in a recessive model. This is the first study to demonstrate an association between a WNT10B polymorphism and the Yin Deficiency pattern of traditional Korean medicine (TKM) in a CI patient population. These results suggest that G-607C might be used as a diagnostic genetic marker for Yin Deficiency pattern in stroke patients and in the development of personalized medical care.

Genetic Association of NPY Gene Polymorphisms with Dampness-Phlegm Pattern in Korean Stroke Patients.

Neuropeptide Y (NPY), which is widely expressed in both the central and peripheral nervous systems, has an important role in a variety of biological fields. In this study, we analyzed the distribution of NPY polymorphisms in dampness-phlegm pattern and non-dampness-phlegm pattern in elderly Korean subjects with cerebral infarction (CI). A total of 1.097 subjects (498 normal subjects and 599 CI patients, including 198 with dampness-phlegm pattern and 401 with non-dampness-phlegm pattern) participated in this study. Genotyping for five SNPs (G-1484A, C-1471T, C-399T, A1201G, and C5325T) was conducted by primer extension. The results were statistically analyzed for genetic association of NPY-polymorphisms with normal versus dampness-phlegm pattern or non-dampness-phlegm pattern subjects. Among the five SNPs tested, the T allele of C-399T has a negative association with the dampness-phlegm pattern and is marked by a decrease in serum cholesterol levels. Furthermore, serum cholesterol levels were significantly higher in dampness-phlegm pattern patients than in non-dampness-phlegm pattern patients.In this study, for the first time, the association of NPY polymorphisms with pattern identification (PI) of traditional Korean medicine (TKM) was analyzed in a large CI patient population.

Nacre-driven water-soluble factors promote wound healing of the deep burn porcine skin by recovering angiogenesis and fibroblast function.

To assess the recovery effect of water-soluble components of nacre on wound healing of burns, water-soluble nacre (WSN) was obtained from powdered nacre. Alterations to WSN-mediated wound healing characteristics were examined in porcine skin with deep second-degree burns; porcine skin was used as a proxy for human. When WSN was applied to a burned area, the burn-induced granulation sites were rapidly filled with collagen, and the damaged dermis and epidermis were restored to the appearance of normal skin. WSN enhanced wound healing recovery properties for burn-induced apoptotic and necrotic cellular damage and spurred angiogenesis. Additionally, WSN-treated murine fibroblast NIH3T3 cells showed increased proliferation and collagen synthesis. Collectively, the findings indicate that WSN improves the process of wound healing in burns by expeditiously restoring angiogenesis and fibroblast activity. WSN may be useful as a therapeutic agent, with superior biocompatibility to powdered nacre, and evoking less discomfort when applied to a wounded area.

Selection of an affinity-matured antibody against a defined epitope by phage display of an immune antibody library.

In a previous study, we generated a murine hepatitis B virus (HBV)-neutralizing monoclonal antibody (mAb), KR127, that binds to an epitope (amino acids 37-45, NSNNPDWDF) of the preS1 antigen. Furthermore, an epitope tag, S1 (NANNPDWDF), was developed for protein tagging. The aim of the present study was to develop a high-affinity antibody to the same preS1 epitope. Mice were immunized with the N-terminal domain of human thrombopoietin fused to the S1 tag (nTPO-S1), and a phage-displayed chimeric Fab library was constructed and screened by panning against nTPO-S1. A high-affinity antibody (3-34) was selected that binds to the preS1 antigen. The IgG molecules of 3-34 showed approximately nine-fold higher affinity (K(D) 1.2 nM) for preS1 compared with KR127 (K(D) 10.4 nM), competed with KR127 for binding to the epitope, and bound to HBV particles. This study provides a simple and efficient way to develop a high-affinity antibody to a defined epitope by phage display of an immune antibody library.

Accelerated cerebral ischemic injury by activated macrophages/microglia after lipopolysaccharide microinjection into rat corpus callosum.

In cerebral ischemic insults, activated inflammatory cells such as microglia and macrophages may be implicated in the pattern and degree of ischemic injury by producing various bioactive mediators. In the present study, we provide the evidence that activated microglia/macrophages accelerate cerebral ischemic injury by overexpression of inducible nitric oxide synthase (iNOS). To activate microglia/macrophages, a potent inflammation inducer lipopolysaccharide (LPS, 5 microg/5 microl) was microinjected into rat corpus callosum. Isolectin B4-positive microglia/macrophages were abundantly observed in ipsilateral hemisphere at 1 day after LPS injection. RT-PCR showed that LPS injection induced iNOS mRNA expression mostly in microglia/macrophages, peaking in intensity at 15 h after LPS injection. While ischemic injury was little evoked in control rats by 2-h middle cerebral artery occlusion (MCAO) followed by 3-h reperfusion, it was markedly increased in rats pre-injected with LPS 1 day before MCAO. However, no significant difference between control and LPS-pretreated groups was observed after 24-h reperfusion. The increased ischemic injury in LPS-treated rats was well correlated with iNOS level expressed over 3 orders of magnitude than in LPS-untreated rats. Immunohistochemical studies showed that iNOS- and nitrotyrosine (a peroxynitrite marker)-positive cells were prominent throughout the infarct area. NOS inhibitors aminoguanidine or N(G)-nitro-L-arginine, simultaneously injected with LPS, reduced the iNOS immunoreactivity and infarct volume, especially in penumbra regions. Total glutathione levels in ischemic regions were decreased more in LPS pre-injected rats than in control ones. Further defining the role of NO in cerebral ischemic insults would provide the rationale for new therapeutic strategies based on modulation of microglial and macrophageal NO production in the brain.