Workplace foodservice meals are associated with higher nutritional quality among adult Korean workers: a nationwide cross-sectional study

BACKGROUND/OBJECTIVES@#Adequate nutritional intake is essential for good health and well-being. We aimed to compare the nutrient intake from homemade meals, meals sourced externally (“eating out”), and meals from workplace foodservices, as well as the potential association between foodservices used and nutritional quality among adult Korean workers. @*SUBJECTS/METHODS@#We used data from the Korea National Health and Nutrition Examination Survey, a nationwide cross-sectional survey on the health and nutritional status of the Korean population. Data from 6,845 workers aged 20–64 years were included. A survey on dietary behavior and nutrition was conducted using the 24-h dietary recall method.Nutritional quality was examined using the index of nutritional quality (INQ) score. Higher INQ scores reflected poorer nutritional quality, with insufficient intake of a higher number of nutrients. Multivariate linear regression was used to identify the association between the foodservices used and INQ scores after adjusting for other covariates. @*RESULTS@#We found that foodservice users exhibited a higher 1-day intake of total energy and macronutrients (all P < 0.05) and lower INQ scores (P < 0.01) than non-users. The INQ scores for total daily meals decreased with the frequency of foodservice use (P < 0.01). A significant association was observed between the non-use of foodservices and INQ scores (β = 0.29, P < 0.01) after adjusting for other covariates. @*CONCLUSIONS@#The use of workplace foodservices contributed to higher dietary nutritional quality among workers. This study highlights the importance of expanding the scope of workplace foodservices to promote higher nutritional quality and healthy dietary habits among workers.

Problems and Reconsideration of the Concept of Public Health Care (Public Health and Medical Services) in South Korea / 의학교육논단

The concept of “public health care (public health and medical services)” as discussed in South Korea is used in an unclear sense, with a meaning unlike the terminology used worldwide. The terms “public health care (public health and medical services)” and “health care (health and medical services)” have the same legal definition in Korea. Globally, “public health care (public health and medical services)” refers to medical services provided to the public that are operated as publicly funded resources, but in Korea, this term is confined to limited medical services prescribed by the government. The following considerations regarding “public health care (public health and medical services)” in Korea are proposed: All medical services performed by the state, regional governments, health care institutions, or health care workers to protect and promote the health of the people should be clearly established as “public health care (public health and medical services)” by definition. The financial burden borne by the state through national health insurance should be increased to an appropriate level to clarify the state's responsibility. Improving public health is an urgent priority in Korea, and this goal can be achieved by improving regional public health through systematic relationships between the state and regional governments, establishing a Ministry of Health, and efficiently allocating public health doctors who are important for providing regional medical care in rural and remote areas. It will be possible to actively deal with infectious diseases at the national level through establishment of a Ministry of Disease Control and Prevention.

The effect of probiotics supplementation in postoperative cancer patients: a prospective pilot study

Purpose@#Microbiota manipulation through selected probiotics may be a promising tool to prevent cancer development as well as onset, to improve clinical efficacy for cancer treatments. The purpose of this study was to evaluate change in microbiota composition after-probiotics supplementation and assessed the efficacy of probiotics in improving quality of life (QOL) in postoperative cancer patients. @*Methods@#Stool samples were collected from 30 cancer patients from February to October 2020 before (group I) and after (group II) 8 weeks of probiotics supplementation. We performed 16S ribosomal RNA gene sequencing to evaluate differences in gut microbiota between groups by comparing gut microbiota diversity, overall composition, and taxonomic signature abundance. The health-related QOL was evaluated through the EORTC Quality of life Questionnaire Core 30 questionnaire. @*Results@#Statistically significant differences were noted in group II; increase of Shannon and Simpson index (P = 0.004 and P = 0.001), decrease of Bacteroidetes and Fusobacteria at the phylum level (P = 0.032 and P = 0.014, retrospectively), increased of beneficial bacteria such as Weissella (0.096% vs. 0.361%, P < 0.004), Lactococcus (0.023% vs. 0.16%, P < 0.001), and Catenibacterium (0.0% vs. 0.005%, P < 0.042) at the genus level. There was a significant improvement in sleep disturbance (P = 0.039) in group II. @*Conclusion@#Gut microbiota in cancer patients can be manipulated by specific probiotic strains, result in an altered microbiota. Microbiota modulation by probiotics can be considered as part of a supplement that helps to increase gut microbiota diversity and improve QOL in cancer patients after surgery.

Role of Primary Care and Challenges for Public–Private Cooperation during the Coronavirus Disease 2019 Pandemic: An Expert Delphi Study in South Korea

Purpose@#The aim of this study was to explore the role of primary care facilities and their support measures in response to coronavirus disease 2019 (COVID-19) and to identify challenges to achieving public–private cooperation in South Korea. @*Materials and Methods@#Twenty-four leading experts were selected and recruited to participate in this iterative web-based Delphi study. An open-ended questionnaire was administered to collect the expert panel’s views in the first round. In the second round, the panel was asked to rate on a 5-point Likert scale their agreement with individual items gleaned from qualitative content analysis of views expressed in the first round. The participants were offered the opportunity to reevaluate and correct their initial responses in subsequent rounds. Responses in the second and following rounds were analyzed using quantitative descriptive statistics. @*Results@#The first and second rounds were completed by 54.2% (n=13/24) and 58.3% (n=14/24) of the selected panel, respectively, while 10 out of these 14 participants completed the third round. The panel cited in-person essential medical services, telehealth for fever/respiratory symptoms, surveillance for influenzae-like illness, and minimization of spread to staff as important and appropriate roles of primary care, which are urgent and feasible during a pandemic. Regarding conditions/support for these roles, the panel indicated that institutional support and funding for separate areas, workforce, and telehealth, along with public-private collaborative governance, are urgent, but not feasible. @*Conclusion@#This study provides guidance on strategies for continuing the required roles of primary care and highlights a need to strengthen public-private partnerships during pandemic events in Korea.

Far-infrared rays enhance mitochondrial biogenesis and GLUT3 expression under low glucose conditions in rat skeletal muscle cells

Far-infrared rays (FIR) are known to have various effects on atoms and molecular structures within cells owing to their radiation and vibration frequencies. The present study examined the effects of FIR on gene expression related to glucose transport through microarray analysis in rat skeletal muscle cells, as well as on mitochondrial biogenesis, at high and low glucose conditions. FIR were emitted from a bio-active material coated fabric (BMCF). L6 cells were treated with 30% BMCF for 24 h in medium containing 25 or 5.5 mM glucose, and changes in the expression of glucose transporter genes were determined. The expression of GLUT3 (Slc2a3) increased 2.0-fold (p < 0.05) under 5.5 mM glucose and 30% BMCF. In addition, mitochondrial oxygen consumption and membrane potential (ΔΨm) increased 1.5- and 3.4-fold (p < 0.05 and p < 0.001), respectively, but no significant change in expression of Pgc-1a, a regulator of mitochondrial biogenesis, was observed in 24 h. To analyze the relationship between GLUT3 expression and mitochondrial biogenesis under FIR, GLUT3 was down-modulated by siRNA for 72 h. As a result, the ΔΨm of the GLUT3 siRNA-treated cells increased 3.0-fold (p < 0.001), whereas that of the control group increased 4.6-fold (p < 0.001). Moreover, Pgc-1a expression increased upon 30% BMCF treatment for 72 h; an effect that was more pronounced in the presence of GLUT3. These results suggest that FIR may hold therapeutic potential for improving glucose metabolism and mitochondrial function in metabolic diseases associated with insufficient glucose supply, such as type 2 diabetes.

Anti-Müllerian Hormone Negatively Regulates Osteoclast Differentiation by Suppressing the Receptor Activator of Nuclear Factor-κB Ligand Pathway

Background@#Multiple members of the transforming growth factor-β (TGF-β) superfamily have well-established roles in bone homeostasis. Anti-Müllerian hormone (AMH) is a member of TGF-β superfamily of glycoproteins that is responsible for the regression of fetal Müllerian ducts and the transcription inhibition of gonadal steroidogenic enzymes. However, the involvement of AMH in bone remodeling is unknown. Therefore, we investigated whether AMH has an effect on bone cells as other TGF-β superfamily members do. @*Methods@#To identify the roles of AMH in bone cells, we administered AMH during osteoblast and osteoclast differentiation, cultured the cells, and then stained the cultured cells with Alizarin red and tartrate-resistant acid phosphatase, respectively. We analyzed the expression of osteoblast- or osteoclast-related genes using real-time polymerase chain reaction and western blot. @*Results@#AMH does not affect bone morphogenetic protein 2-mediated osteoblast differentiation but inhibits receptor activator of nuclear factor-κB (NF-κB) ligand-induced osteoclast differentiation. The inhibitory effect of AMH on osteoclast differentiation is mediated by IκB-NF-κB signaling. @*Conclusions@#AMH negatively regulates osteoclast differentiation without affecting osteoblast differentiation.

Role of Primary Care and Challenges for Public–Private Cooperation during the Coronavirus Disease 2019 Pandemic: An Expert Delphi Study in South Korea

Purpose@#The aim of this study was to explore the role of primary care facilities and their support measures in response to coronavirus disease 2019 (COVID-19) and to identify challenges to achieving public–private cooperation in South Korea. @*Materials and Methods@#Twenty-four leading experts were selected and recruited to participate in this iterative web-based Delphi study. An open-ended questionnaire was administered to collect the expert panel’s views in the first round. In the second round, the panel was asked to rate on a 5-point Likert scale their agreement with individual items gleaned from qualitative content analysis of views expressed in the first round. The participants were offered the opportunity to reevaluate and correct their initial responses in subsequent rounds. Responses in the second and following rounds were analyzed using quantitative descriptive statistics. @*Results@#The first and second rounds were completed by 54.2% (n=13/24) and 58.3% (n=14/24) of the selected panel, respectively, while 10 out of these 14 participants completed the third round. The panel cited in-person essential medical services, telehealth for fever/respiratory symptoms, surveillance for influenzae-like illness, and minimization of spread to staff as important and appropriate roles of primary care, which are urgent and feasible during a pandemic. Regarding conditions/support for these roles, the panel indicated that institutional support and funding for separate areas, workforce, and telehealth, along with public-private collaborative governance, are urgent, but not feasible. @*Conclusion@#This study provides guidance on strategies for continuing the required roles of primary care and highlights a need to strengthen public-private partnerships during pandemic events in Korea.

Anti-Müllerian Hormone Negatively Regulates Osteoclast Differentiation by Suppressing the Receptor Activator of Nuclear Factor-κB Ligand Pathway

Background@#Multiple members of the transforming growth factor-β (TGF-β) superfamily have well-established roles in bone homeostasis. Anti-Müllerian hormone (AMH) is a member of TGF-β superfamily of glycoproteins that is responsible for the regression of fetal Müllerian ducts and the transcription inhibition of gonadal steroidogenic enzymes. However, the involvement of AMH in bone remodeling is unknown. Therefore, we investigated whether AMH has an effect on bone cells as other TGF-β superfamily members do. @*Methods@#To identify the roles of AMH in bone cells, we administered AMH during osteoblast and osteoclast differentiation, cultured the cells, and then stained the cultured cells with Alizarin red and tartrate-resistant acid phosphatase, respectively. We analyzed the expression of osteoblast- or osteoclast-related genes using real-time polymerase chain reaction and western blot. @*Results@#AMH does not affect bone morphogenetic protein 2-mediated osteoblast differentiation but inhibits receptor activator of nuclear factor-κB (NF-κB) ligand-induced osteoclast differentiation. The inhibitory effect of AMH on osteoclast differentiation is mediated by IκB-NF-κB signaling. @*Conclusions@#AMH negatively regulates osteoclast differentiation without affecting osteoblast differentiation.

Far-infrared rays enhance mitochondrial biogenesis and GLUT3 expression under low glucose conditions in rat skeletal muscle cells

Far-infrared rays (FIR) are known to have various effects on atoms and molecular structures within cells owing to their radiation and vibration frequencies. The present study examined the effects of FIR on gene expression related to glucose transport through microarray analysis in rat skeletal muscle cells, as well as on mitochondrial biogenesis, at high and low glucose conditions. FIR were emitted from a bio-active material coated fabric (BMCF). L6 cells were treated with 30% BMCF for 24 h in medium containing 25 or 5.5 mM glucose, and changes in the expression of glucose transporter genes were determined. The expression of GLUT3 (Slc2a3) increased 2.0-fold (p < 0.05) under 5.5 mM glucose and 30% BMCF. In addition, mitochondrial oxygen consumption and membrane potential (ΔΨm) increased 1.5- and 3.4-fold (p < 0.05 and p < 0.001), respectively, but no significant change in expression of Pgc-1a, a regulator of mitochondrial biogenesis, was observed in 24 h. To analyze the relationship between GLUT3 expression and mitochondrial biogenesis under FIR, GLUT3 was down-modulated by siRNA for 72 h. As a result, the ΔΨm of the GLUT3 siRNA-treated cells increased 3.0-fold (p < 0.001), whereas that of the control group increased 4.6-fold (p < 0.001). Moreover, Pgc-1a expression increased upon 30% BMCF treatment for 72 h; an effect that was more pronounced in the presence of GLUT3. These results suggest that FIR may hold therapeutic potential for improving glucose metabolism and mitochondrial function in metabolic diseases associated with insufficient glucose supply, such as type 2 diabetes.

Korean Guideline for Managing In-flight Medical Events / 항공우주의학회지

The cabin environment has many physiological effects on commercial aircraft passengers and medical providers, and environmental stress factors exist. Therefore, it is important for medical providers to understand the effects of aviation physiology and cabin environment on the human body. It should also be remembered that these physiological changes and environmental stress factors can affect passengers as well as flight crew and also medical equipment. Providing medical assistance during a flight offers a number of unique challenges including lower cabin pressure, tight quarters, crowded conditions, and loud background noise. The purpose of this Korean guideline is to offer an overview on various in-flight emergencies that could be anticipated and to outline treatment priorities.

Association between Suicidal Ideation and Causes of Primary Care Visits: A Cross-Sectional Study to Identify Patients with Suspected Suicidal Ideation

Objective@#Suicide victims are likely to visit a primary care provider within 1 month of the suicide attempt. However, it is impossible for primary care providers to screen all patients for suicidal ideation or attempts. We, therefore, aimed to investigate potential differences in the chief diagnoses received by primary care patients with and without suicidal ideation, as this information may provide clues and predict patients at risk of suicide. @*Methods@#This cross-sectional study included 1,211 Korean adults aged ≥20 years who had participated in the Korea National Health and Nutrition Examination Survey during 2014 and provided information about their histories of suicidal ideation and visits to primary care providers. Multiple logistic regression analyses were used to examine whether suicidal ideation was associated with specific diseases after controlling for age, sex, household income, education, occupation, marital status, smoking, alcohol consumption, and physical activity. @*Results@#Among primary care patients, the sample-weighted percentage of suicidal ideation was approximately 12%. The diagnoses of neoplasm and mental disorder were associated with a higher likelihood of suicidal ideation {odds ratio (OR) [95% confidence interval (CI)] 8.32 (1.01–68.56) and 6.19 (1.72–22.33), respectively}. Notably, diseases of the musculoskeletal system and connective tissue were also associated with suicidal ideation [OR (95% CI): 1.93 (1.09–3.43)]. @*Conclusion@#The observed visit patterns and correlations of certain diagnoses with suicidal ideation suggest that primary care physicians should pay attention to patients with relevant disorders, consider screening suicidal ideation, and properly consult to a psychiatrist.

Bone Cell Communication Factors Provide a New Therapeutic Strategy for Osteoporosis / 전남의대학술지

Bone homeostasis is strictly regulated by the balance between bone resorption by osteoclasts and bone formation by osteoblasts. Many studies have shown that osteoclasts affect osteoblasts, and vice versa, through diffusible paracrine factors, cell-cell contact, and cell-bone matrix interactions to achieve the correct balance between osteoclastic and osteoblastic activities in the basic multicellular unit (BMU). The strict regulation that occurs during bone remodeling hinders the long-term use of the currently available antiresorptive agents and anabolic agents for the treatment of osteoporosis. To overcome these limitations, it is necessary to develop novel agents that simultaneously inhibit bone resorption, promote bone formation, and decouple resorption from formation. Therefore, a more detailed understanding of the mechanisms involved in osteoclast-osteoblast communication during bone remodeling is necessary.

Expression of potassium channel genes predicts clinical outcome in lung cancer

Lung cancer is the most common cause of cancer deaths worldwide and several molecular signatures have been developed to predict survival in lung cancer. Increasing evidence suggests that proliferation and migration to promote tumor growth are associated with dysregulated ion channel expression. In this study, by analyzing high-throughput gene expression data, we identify the differentially expressed K⁺ channel genes in lung cancer. In total, we prioritize ten dysregulated K⁺ channel genes (5 up-regulated and 5 down-regulated genes, which were designated as K-10) in lung tumor tissue compared with normal tissue. A risk scoring system combined with the K-10 signature accurately predicts clinical outcome in lung cancer, which is independent of standard clinical and pathological prognostic factors including patient age, lymph node involvement, tumor size, and tumor grade. We further indicate that the K-10 potentially predicts clinical outcome in breast and colon cancers. Molecular signature discovered through K⁺ gene expression profiling may serve as a novel biomarker to assess the risk in lung cancer.

Profiling of remote skeletal muscle gene changes resulting from stimulation of atopic dermatitis disease in NC/Nga mouse model

Although atopic dermatitis (AD) is known to be a representative skin disorder, it also affects the systemic immune response. In a recent study, myoblasts were shown to be involved in the immune regulation, but the roles of muscle cells in AD are poorly understood. We aimed to identify the relationship between mitochondria and atopy by genome-wide analysis of skeletal muscles in mice. We induced AD-like symptoms using house dust mite (HDM) extract in NC/Nga mice. The transcriptional profiles of the untreated group and HDM-induced AD-like group were analyzed and compared using microarray, differentially expressed gene and functional pathway analyses, and protein interaction network construction. Our microarray analysis demonstrated that immune response-, calcium handling-, and mitochondrial metabolism-related genes were differentially expressed. In the Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology pathway analyses, immune response pathways involved in cytokine interaction, nuclear factor-kappa B, and T-cell receptor signaling, calcium handling pathways, and mitochondria metabolism pathways involved in the citrate cycle were significantly upregulated. In protein interaction network analysis, chemokine family-, muscle contraction process-, and immune response-related genes were identified as hub genes with many interactions. In addition, mitochondrial pathways involved in calcium signaling, cardiac muscle contraction, tricarboxylic acid cycle, oxidation-reduction process, and calcium-mediated signaling were significantly stimulated in KEGG and Gene Ontology analyses. Our results provide a comprehensive understanding of the genome-wide transcriptional changes of HDM-induced AD-like symptoms and the indicated genes that could be used as AD clinical biomarkers.

Far-infrared radiation stimulates platelet-derived growth factor mediated skeletal muscle cell migration through extracellular matrix-integrin signaling

Despite increased evidence of bio-activity following far-infrared (FIR) radiation, susceptibility of cell signaling to FIR radiation-induced homeostasis is poorly understood. To observe the effects of FIR radiation, FIR-radiated materials-coated fabric was put on experimental rats or applied to L6 cells, and microarray analysis, quantitative real-time polymerase chain reaction, and wound healing assays were performed. Microarray analysis revealed that messenger RNA expressions of rat muscle were stimulated by FIR radiation in a dose-dependent manner in amount of 10% and 30% materials-coated. In 30% group, 1,473 differentially expressed genes were identified (fold change [FC] > 1.5), and 218 genes were significantly regulated (FC > 1.5 and p < 0.05). Microarray analysis showed that extracellular matrix (ECM)-receptor interaction, focal adhesion, and cell migration-related pathways were significantly stimulated in rat muscle. ECM and platelet-derived growth factor (PDGF)-mediated cell migration-related genes were increased. And, results showed that the relative gene expression of actin beta was increased. FIR radiation also stimulated actin subunit and actin-related genes. We observed that wound healing was certainly promoted by FIR radiation over 48 h in L6 cells. Therefore, we suggest that FIR radiation can penetrate the body and stimulate PDGF-mediated cell migration through ECM-integrin signaling in rats.

Comparison of Fatigue Severity and Quality of Life between Unexplained Fatigue Patients and Explained Fatigue Patients / 가정의학회지

BACKGROUND: Recently, despite the high prevalence of fatigue in patients, there is a lack of research on the quality of life (QoL) in unexplained fatigue patients, indicating that they are not properly diagnosed and treated. The aim of this study was to compare fatigue severity and QoL between patients with explained and unexplained fatigue. METHODS: The study consisted of 200 Korean adults who complained of fatigue without underlying disease. Fatigue Severity Scale, Short Form Health Survey-36 version 2 (SF-36v2), and Beck Depression Inventory-II (BDI-II) self-questionnaires were administered. Participants were dichotomized to two groups, namely, patients with unexplained or explained fatigue, sorted according to laboratory examination results. The chi-square test, t-test, and Wilcoxon rank-sum test were used, and analysis of covariance was calculated after adjusting for age, sex, body mass index, smoking status, and physical component summary (PCS) of SF-36v2 or BDI-II. RESULTS: PCS of SF-36v2 between the two groups showed significant difference. Compared to patients with explained fatigue, those with unexplained fatigue showed lower physical component scores of QoL. CONCLUSION: QoL of patients with unexplained fatigue could largely diminish than those with explained fatigue. The primary clinician should be aware of poor QoL in patients with unexplained fatigue to identify who is in need of more attention and intervention.

Effect of Stents Coated with Artemisinin or Dihydroartemisinin in a Porcine Coronary Restenosis Model

BACKGROUND AND OBJECTIVES: Artemisinin and dihydroartemisinin are drugs used to treat malaria. These drugs suppress inflammatory reactions. The aim of this study was to examine the anti-intima hyperplasia effect of a novel drug-eluting stent with artemisinin or dihydroartemisinin in a porcine coronary restenosis model. MATERIALS AND METHODS: Pigs were randomized into four groups; in the first, the coronary arteries (20 pigs, a total of 40 coronary arteries, with 10 coronary arteries in each group) was implanted with bare metal stents (BMS, n=10); the second group was given polymer-coated stents (PCS, n=10); the third group was treated with artemisinin-eluting stents (AES, n=10); and the fourth group was given dihydroartemisinin-eluting stents (DAES, n=10). Histopathologic analysis was performed 28 days after stenting. RESULTS: The injury and fibrin scores among the four groups were not significantly different. However, the internal elastic lamina, lumen area, and neointima area were significantly different. Moreover, the percent area of stenosis (46.2±18.66% in BMS vs. 89.4±10.92% in PCS vs. 83.3±17.07% in AES vs. 36.7±11.20% in DAES, p<0.0001) and inflammation score (1.0 [range: 1.0-1.0] vs. 3.0 [range: 2.25-3.0] vs. 3.0 [range: 1.0-3.0] vs. 2.0 [range: 1.75-3.0] in BMS, PCS, AES, and DAES, respectively; p<0.001) were markedly decreased in the DAES group compared to the PCS group. CONCLUSION: DES, which uses a natural substance, dihydroartemisinin, showed a neointima and inflammatory suppressive effect in a porcine coronary restenosis model.

The Control of Drug Release and Vascular Endothelialization after Hyaluronic Acid-Coated Paclitaxel Multi-Layer Coating Stent Implantation in Porcine Coronary Restenosis Model

BACKGROUND AND OBJECTIVES: Hyaluronic acid (HA) is highly biocompatible with cells and the extracellular matrix. In contrast to degradation products of a synthetic polymer, degradation products of HA do not acidify the local environment. The aim of this study was to fabricate an HA-coated paclitaxel (PTX)-eluting stent via simple ionic interactions and to evaluate its effects in vitro and in vivo. MATERIALS AND METHODS: HA and catechol were conjugated by means of an activation agent, and then the stent was immersed in this solution (resulting in a HA-coated stent). After that, PTX was immobilized on the HA-coated stent (resulting in a hyaluronic acid-coated paclitaxel-eluting stent [H-PTX stent]). Study groups were divided into 4 groups: bare metal stent (BMS), HA, H-PTX, and poly (L-lactide)-coated paclitaxel-eluting stent (P-PTX). Stents were randomly implanted in a porcine coronary artery. After 4 weeks, vessels surrounding the stents were isolated and subjected to various analyses. RESULTS: Smoothness of the surface was maintained after expansion of the stent. In contrast to a previous study on a PTX-eluting stent, in this study, the PTX was effectively released up to 14 days (a half amount of PTX in 4 days). The proliferation of smooth muscle cells was successfully inhibited (by 80.5±12.11% at 7 days of culture as compared to the control) by PTX released from the stent. Animal experiments showed that the H-PTX stent does not induce an obvious inflammatory response. Nevertheless, restenosis was clearly decreased in the H-PTX stent group (9.8±3.25%) compared to the bare-metal stent group (29.7±8.11%). CONCLUSION: A stent was stably coated with PTX via simple ionic interactions with HA. Restenosis was decreased in the H-PTX group. These results suggest that HA, a natural polymer, is suitable for fabrication of drug-eluting stents (without inflammation) as an alternative to a synthetic polymer.

Differential Expression of Amelogenin, Enamelin and Ameloblastin in Rat Tooth Germ Development

Tooth development shows dynamic morphological changes from the stages of cap to hard tissue formation and is strictly regulated during development. In the present study, we compared expression and localization of 3 major enamel matrix proteins in rats: amelogenin, enamel and ameloblastin. DD-PCR and RT-PCR revealed differential expression of the major proteins from the cap stage to root stage. Immunofluorescence staining results indicated that amelogenin was not detected in either inner enamel epithelium or reduced enamel epithelium, but highly immunoreactive in preameloblasts and ameloblasts; in addition, it was sporadically expressed in preodontoblasts abutting preameloblasts. Ameloblastin expression was also observed in not only differentiated ameloblasts but also osteoblasts. Immunoreactivity to ameloblastin in ameloblasts was strong in Tomes' processes. Enamelin was exclusively localized along the entire newly formed and maturing enamel. Enamelin was largely localized in near Tomes' processes and enamel rods in maturing enamel. Alendronate treatment resulted in down-regulation of amelogenin and ameloblastin at both transcription and translation levels; whereas, enamelin expression was unchanged in response to the treatment. These results suggested that amelogenin, ameloblastin and enamelin might be implicated in cell differentiation, adhesion of ameloblasts to enamel and enamel crystallization during enamel matrix formation, respectively.

Association between Leukocyte Mitochondrial DNA Copy Number and Regular Exercise in Postmenopausal Women / 가정의학회지

BACKGROUND: Previous studies suggest that habitual exercise can improve skeletal mitochondrial function; however, to date, the association between exercise and mitochondrial function in peripheral leukocytes has not been reported. The aim of this study was to evaluate the relationship between regular exercise and mitochondrial function by measuring leukocyte mitochondrial DNA (mtDNA) copy number in postmenopausal women. METHODS: This cross-sectional study included 144 relatively healthy, non-diabetic, non-smoking, postmenopausal women. Clinical parameters, including anthropometric measurements and cardio-metabolic parameters, were assessed. Regular exercise was defined as at least 150 minutes per week of moderate-intensity activity, or an equivalent combination of moderate and vigorous-intensity activity, over a duration of at least 6 months. Leukocyte mtDNA copy numbers were measured using real-time polymerase chain reaction assays, and these were normalized to the β-globin copy number to give the relative mtDNA copy number. RESULTS: The mtDNA copy number of peripheral leukocytes was significantly greater in the exercise group (1.33±0.02) than in the no exercise group (1.05±0.02, P<0.01). Stepwise multiple regression analysis showed that regular exercise was independently associated with mtDNA copy number (β=0.25, P<0.01) after adjusting for the variables age, body mass index, waist-to-hip ratio, systolic and diastolic blood pressure, homeostasis model assessment of insulin resistance value, and levels of high-density lipoprotein cholesterol, triglycerides, and homocysteine. CONCLUSION: Regular exercise is associated with greater leukocyte mtDNA copy number in postmenopausal women.