The programmed cell death ligand 1 (PD-L1) and its receptor programmed cell death 1 (PD-1) deliver inhibitory signals to regulate immunological tolerance during immune-mediated diseases. However, the role of PD-1 signaling and its blockade effect on human dental pulp stem cells (hDPSCs) differentiation into the osteo-/odontogenic lineage remain unknown. We show here that PD-L1 expression, but not PD-1, is downregulated during osteo-/odontogenic differentiation of hDPSCs. Importantly, PD-L1/PD-1 signaling has been shown to negatively regulate the osteo-/odontogenic differentiation of hDPSCs. Mechanistically, depletion of either PD-L1 or PD-1 expression increased ERK and AKT phosphorylation levels through the upregulation of Ras enzyme activity, which plays a pivotal role during hDPSCs osteo-/odontogenic differentiation. Treatment with nivolumab (a human anti-PD-1 monoclonal antibody), which targets PD-1 to prevent PD-L1 binding, successfully enhanced osteo-/odontogenic differentiation of hDPSCs through enhanced Ras activity-mediated phosphorylation of ERK and AKT. Our findings underscore that downregulation of PD-L1 expression accompanies during osteo-/odontogenic differentiation, and hDPSCs-intrinsic PD-1 signaling inhibits osteo-/odontogenic differentiation. These findings provide a significant basis that PD-1 blockade could be effective immunotherapeutic strategies in hDPSCs-mediated dental pulp regeneration.
B7-H1 Antigen/metabolism* ; Dental Pulp/metabolism* ; Humans ; Programmed Cell Death 1 Receptor/metabolism* ; Regeneration ; Stem Cells

An abnormal reorganization of the dentate gyrus and neurotoxic events are important phenotypes in the hippocampus of patients with temporal lobe epilepsy (TLE). The effects of morin, a bioflavonoid constituent of many herbs and fruits, on epileptic seizures have not yet been elucidated, though its beneficial effects, such as its anti-inflammatory and neuroprotective properties, are well-described in various neurodegenerative diseases. In the present study, we investigated whether treatment with morin hydrate (MH) can reduce the susceptibility to seizures, granule cell dispersion (GCD), mammalian target of rapamycin complex 1 (mTORC1) activity, and the increases in the levels of apoptotic molecules and inflammatory cytokines in the kainic acid (KA)-induced seizure mouse model. Our results showed that oral administration of MH could reduce susceptibility to seizures and lead to the inhibition of GCD and mTORC1 activity in the KA-treated hippocampus. Moreover, treatment with MH significantly reduced the increased levels of apoptotic signaling molecules and pro-inflammatory mediators in the KA-treated hippocampus compared with control mice, suggesting a neuroprotective role. Therefore, these results suggest that morin has a therapeutic potential against epilepsy through its abilities to inhibit GCD and neurotoxic events in the in vivo hippocampus.
Administration, Oral ; Animals ; Cytokines ; Dentate Gyrus ; Epilepsy ; Epilepsy, Temporal Lobe ; Fruit ; Hippocampus ; Humans ; Kainic Acid ; Mice ; Neurodegenerative Diseases ; Neuroprotection ; Phenotype ; Seizures* ; Sirolimus

Lung cancer has high mortality and incidence rates. The leading causes of lung cancer are smoking and radon exposure. Indeed, the World Health Organization (WHO) has categorized radon as a carcinogenic substance causing lung cancer. Radon is a natural, radioactive substance; it is an inert gas that mainly exists in soil or rock. The gas decays into radioactive particles called radon progeny that can enter the human body through breathing. Upon entering the body, these radioactive elements release α-rays that affect lung tissue, causing lung cancer upon long-term exposure thereto. Epidemiological studies first outlined a high correlation between the incidence rate of lung cancer and exposure to radon progeny among miners in Europe. Thereafter, data and research on radon exposure and lung cancer incidence in homes have continued to accumulate. Many international studies have reported increases in the risk ratio of lung cancer when indoor radon concentrations inside the home are high. Although research into indoor radon concentrations and lung cancer incidence is actively conducted throughout North America and Europe, similar research is lacking in Korea. Recently, however, studies have begun to accumulate and report important data on indoor radon concentrations across the nation. In this study, we aimed to review domestic and foreign research into indoor radon concentrations and to outline correlations between indoor radon concentrations in homes and lung cancer incidence, as reported in ecological studies thereof. Herein, we noted large differences in radon concentrations between and within individual countries. For Korea, we observed tremendous differences in indoor radon concentrations according to region and year of study, even within the same region. In correlation analysis, lung cancer incidence was not found to be higher in areas with high indoor radon concentrations in Korea. Through our review, we identified a need to implement a greater variety of statistical analyses in research on indoor radon concentrations and lung cancer incidence. Also, we suggest that cohort research or patient-control group research into radon exposure and lung cancer incidence that considers smoking and other factors is warranted.
Cohort Studies ; Elements, Radioactive ; Epidemiologic Studies ; Europe ; Human Body ; Incidence ; Korea ; Lung Neoplasms* ; Lung* ; Miners ; Mortality ; North America ; Odds Ratio ; Radon* ; Respiration ; Smoke ; Smoking ; Soil ; World Health Organization

Serosurveillance for zoonotic diseases in small mammals and detection of chiggers, the vector of Orientia tsutsugamushi, were conducted from September 2014 to August 2015 in Gwangju Metropolitan Area. Apodemus agrarius was the most commonly collected small mammals (158; 91.8%), followed by Myodes regulus (8; 4.6%), and Crocidura lasiura (6; 3.5%). The highest seroprevalence of small mammals for O. tsutsugamushi (41; 26.3%) was followed by hantaviruses (24; 15.4%), Rickettsia spp. (22; 14.1%), and Leptospira (2; 1.3%). A total of 3,194 chiggers were collected from small mammals, and 1,236 of 3,194 chiggers were identified with 7 species of 3 genera: Leptotrombidium scutellare was the most commonly collected species (585; 47.3%), followed by L. orientale (422; 34.1%), Euchoengastia koreaensis (99; 8.0%), L. palpale (58; 4.7%), L. pallidum (36; 2.9%), Neotrombicula gardellai (28; 2.3%), and L. zetum (8; 0.6%). L. scutellare was the predominant species. Three of 1,236 chigger mites were positive for O. tsutsugamushi by PCR. As a result of phylogenetic analysis, the O. tsutsugamushi strain of chigger mites had sequence homology of 90.1-98.2% with Boryong. This study provides baseline data on the distribution of zoonotic diseases and potential vectors for the development of prevention strategies of vector borne diseases in Gwangju metropolitan area.
Animals ; Arvicolinae ; Chungcheongnam-do ; Globus Pallidus ; Gwangju* ; Hantavirus ; Korea* ; Leptospira ; Mammals* ; Mites ; Murinae ; Orientia tsutsugamushi* ; Polymerase Chain Reaction* ; Rickettsia ; Rodentia ; Sequence Homology ; Seroepidemiologic Studies ; Trombiculidae* ; Zoonoses*

Anaplastic lymphoma kinase (ALK) fusion is a common mechanism underlying pathogenesis of non-small cell lung carcinoma (NSCLC) where these rearrangements represent important diagnostic and therapeutic targets. In this study, we found a new ALK fusion gene, SEC31A-ALK, in lung carcinoma from a 53-year-old Korean man. The conjoined region in the fusion transcript was generated by the fusion of SEC31A exon 21 and ALK exon 20 by genomic rearrangement, which contributed to generation of an intact, in-frame open reading frame. SEC31A-ALK encodes a predicted fusion protein of 1,438 amino acids comprising the WD40 domain of SEC31A at the N-terminus and ALK kinase domain at the C-terminus. Fluorescence in situ hybridization studies suggested that SEC31A-ALK was generated by an unbalanced genomic rearrangement associated with loss of the 3'-end of SEC31A. This is the first report of SEC31A-ALK fusion transcript in clinical NSCLC, which could be a novel diagnostic and therapeutic target for patients with NSCLC.
Adenocarcinoma* ; Amino Acids ; Exons ; Fluorescence ; Humans ; In Situ Hybridization ; Lung Neoplasms ; Lung* ; Lymphoma ; Middle Aged ; Open Reading Frames ; Phosphotransferases ; Translocation, Genetic

PURPOSE: This study was designed to compare the amount of polymerization shrinkage of dual-cure resin cements according to different polymerization modes and to determine the effect of light activation on the degree of polymerization. MATERIALS AND METHODS: Four kinds of dual-cure resin cements were investigated: Smartcem 2, Panavia F 2.0, Clearfil SA Luting and Zirconite. Each material was tested in three different polymerization modes: self-polymerization only, immediate light polymerization and 5 minutes-delayed light polymerization. The time-dependent polymerization shrinkage-strain was evaluated for 30 minutes by Bonded-disk method at 37degrees C. Five recordings of each material with three different modes were taken. Data were analyzed using one-way ANOVA and multiple comparison Scheffe'test (alpha=.05). RESULTS: All materials, except Panavia F 2.0, exhibited the highest polymerization shrinkage-strain through delayed light-activated polymerization. No significant difference between light activation modes was found with Panavia F 2.0. All materials exhibited more than 90% of polymerization rate in the immediate or delayed light activated group within 10 minutes. CONCLUSION: As a clinical implication of this study, the application of delayed light activation mode to dual-cure resin cements is advantageous in terms of degree of polymerization.
Polymerization* ; Polymers* ; Resin Cements*

BACKGROUND/AIMS: The meaning of specialized intestinal metaplasia (SIM) in the diagnosis of Barrett's esophagus (BE) is not clear. This study was designed to determine the clinical significance of SIM in the diagnosis of Barrett's esophagus. MATERIALS AND METHODS: Biopsies were taken from 601 subjects with endoscopically suspected columnar-lined esophagus. Under light microscopy with Alcian-blue stain, SIM was identified. Demographic characteristics, gastroesophageal (GE) reflux symptoms and endoscopic findings were compared between the SIM-present group and the SIM-absent group. RESULTS: Among 601 subjects, 184 (30.6%) were confirmed by pathology to have SIM. Age over 40 years (P<0.001) and a medication history of proton pump inhibitor or H2 blocker were found more frequently in the SIM-present group (P=0.01) than in the SIM-absent group. Any of 7 GE reflux symptoms (heartburn, acid regurgitation, chest pain, hoarseness, globus sensation, cough and epigastric soreness) were more frequent in the SIM-present group than SIM-absent group (P<0.001). Specifically, heartburn, chest pain and cough were significantly more common in the SIM-present group. There was no clinically significant difference associated with endoscopic findings or other clinical characteristics. CONCLUSIONS: When subjects with endoscopically suspected BE are analyzed based on the presence or absence of SIM, the SIM-present group was significantly associated with GE reflux symptoms suggestive of frequent GE reflux. However, the presence of SIM did not correlate with endoscopic findings.
Barrett Esophagus ; Biopsy ; Chest Pain ; Cough ; Esophagus ; Gastroesophageal Reflux ; Heartburn ; Hoarseness ; Light ; Metaplasia ; Microscopy ; Prospective Studies ; Proton Pumps ; Sensation

PURPOSE: The Tox-Info system is a poisonous substance information database developed by the Korean National Institute of Food and Drug Safety Evaluation. The aim of this study was to estimate the coverage effectiveness of the Tox-Info system by comparing the toxic substances included in the database with the distribution of the toxic substances implicated in the cases of intoxicated patients presenting to emergency departments. The secondary aim of the study was to propose any additional substances that should be added to the database. METHODS: We retrospectively reviewed the medical records of patients suffering with toxic exposure who had visited any of 12 selected emergency departments in Korea from January 2010 to December 2011. The identified toxic substances were classified into groups including prescription drugs, agricultural chemicals, household products, animals or plants, herbal drugs, and others. We calculated the coverage rate of the Tox-Info database relative to the number of intoxication cases and the type of toxic substances involved. RESULTS: A total of 5,840 intoxicated patient records were collected. Their mean age was 46.6+/-20.5 years and 56.2% were female. Of the total intoxication cases, 87.8% of the identified toxic substances were included in the Tox-Info database, while only 41.6% of all of the types of identified toxic substances were included. Broken down by category, 122 prescription drugs, 15 agricultural chemicals, 12 household products, 14 animals or plants and 2 herbal drugs involved in poisoning cases were not included in the Tox-info database. CONCLUSION: This study demonstrated the clinical usefulness of the Tox-Info system. While 87.8% of the substances involved in the cases were included in the Tox-Info database, the database should be continuously updated in order to include even the most uncommon toxic substances.
Agrochemicals ; Animals ; Emergencies ; Female ; Household Products ; Humans ; Korea ; Medical Records ; Prescription Drugs ; Retrospective Studies ; Stress, Psychological

BACKGROUND/AIMS: Chronic gastritis is a common finding during endoscopy and it is very important to describe it correctly. This study was designed to evaluate the distribution of endoscopic gastritis and the differences according to age, sex or area. MATERIALS AND METHODS: A clinical analysis was conducted on 25,536 subjects who had undergone an upper endoscopy for routine health check-up. Endoscopic gastritis was classified into four types, superficial gastritis, erosive gastritis, atrophic gastritis and intestinal metaplasia. The distribution of the four types of gastritis was evaluated according to sex, age and area. RESULTS: 51.6% of the patients had experienced at least one of the symptoms (epigastric pain or discomfort, soarness, dyspepsia, abdominal pain) on at least a few occasions during the previous year. The incidence of normal gastric finding was 3,593 (14.1%). 21,943 (85.9%) subjects have at least more than one of endoscopic gastritis. The number of cases with superficial gastritis was 7,983 (31.3%), erosive gastritis 6,054 (23.7%), atrophic gastritis 6,918 (27.1%), and intestinal metaplasia 1,181 (7.1%). Erosive gastritis, atrophic gastritis and intestinal metaplasia were more frequent in men than women (P<0.001) and in the older age group (> or =60 years) than younger age group (P<0.001). CONCLUSIONS: The prevalence of endoscopic gastritis was very common, 85.9%. In addition, erosive gastritis, atrophic gastritis and intestinal metaplasia were more frequent in men and in the older age group, which is similar to gastric cancer or peptic ulcer. Cautious regular endoscopic follow-up might be necessary regardless of gastrointestinal symptoms in Korea.
Dyspepsia ; Endoscopy ; Female ; Gastritis ; Gastritis, Atrophic ; Helicobacter pylori ; Humans ; Incidence ; Korea ; Male ; Metaplasia ; Peptic Ulcer ; Prevalence ; Stomach Neoplasms

BACKGROUND/AIMS: Chronic gastritis is a common finding during endoscopy and it is very important to describe it correctly. This study was designed to evaluate the distribution of endoscopic gastritis and the differences according to age, sex or area. MATERIALS AND METHODS: A clinical analysis was conducted on 25,536 subjects who had undergone an upper endoscopy for routine health check-up. Endoscopic gastritis was classified into four types, superficial gastritis, erosive gastritis, atrophic gastritis and intestinal metaplasia. The distribution of the four types of gastritis was evaluated according to sex, age and area. RESULTS: 51.6% of the patients had experienced at least one of the symptoms (epigastric pain or discomfort, soarness, dyspepsia, abdominal pain) on at least a few occasions during the previous year. The incidence of normal gastric finding was 3,593 (14.1%). 21,943 (85.9%) subjects have at least more than one of endoscopic gastritis. The number of cases with superficial gastritis was 7,983 (31.3%), erosive gastritis 6,054 (23.7%), atrophic gastritis 6,918 (27.1%), and intestinal metaplasia 1,181 (7.1%). Erosive gastritis, atrophic gastritis and intestinal metaplasia were more frequent in men than women (P<0.001) and in the older age group (> or =60 years) than younger age group (P<0.001). CONCLUSIONS: The prevalence of endoscopic gastritis was very common, 85.9%. In addition, erosive gastritis, atrophic gastritis and intestinal metaplasia were more frequent in men and in the older age group, which is similar to gastric cancer or peptic ulcer. Cautious regular endoscopic follow-up might be necessary regardless of gastrointestinal symptoms in Korea.
Dyspepsia ; Endoscopy ; Female ; Gastritis ; Gastritis, Atrophic ; Helicobacter pylori ; Humans ; Incidence ; Korea ; Male ; Metaplasia ; Peptic Ulcer ; Prevalence ; Stomach Neoplasms