Thyroid hormones play crucial roles in normal neurodevelopment of fetus and child. Many chemicals can affect control and homeostasis of thyroid hormones, and eventually lead to various adverse health effects including neurodevelopmental disorders. Perfluoroalkyl substances (PFASs) are among the thyroid disrupting chemicals that can be encountered among general human population. Due to their unique physicochemical characteristics, PFASs have been used as surfactants and surface coating materials in many applications. Therefore, PFASs have been frequently detected in humans and environment worldwide. In cross-sectional studies using nationally representative general human populations of United States, several PFASs have shown significant associations with thyroid hormones. Moreover, among pregnant women and their infants, not only major PFASs such as perfluorooctane sulfonic acid and perfluorooctanoic acid, but also those with shorter or longer carbon chains showed significant associations with thyroid hormones. Often demographic characteristics such as sex, age, and disease status appear to influence the associations between PFASs exposure and thyroid hormones. In general, major PFASs showed hypothyroidism effects among pregnant women and infants. As 8 carbon based PFASs have been phased out, those with shorter or longer carbon chains have been used in growing amount as replacement. However, only limited information is available for their occurrences and toxicity among humans. Further investigations on these substituting PFASs are required. In addition, efforts are warranted to identify sources of and mitigate exposure to these thyroid disrupting chemicals especially during pregnancy and early stages of life.
Carbon ; Child ; Cross-Sectional Studies ; Environmental Monitoring ; Female ; Fetus ; Homeostasis ; Humans* ; Hypothyroidism ; Infant ; Neurodevelopmental Disorders ; Pregnancy ; Pregnant Women ; Surface-Active Agents ; Thyroid Gland* ; Thyroid Hormones* ; United States

This paper reviews the published literature that is concerned with color vision impairment from industrial and environmental exposure to neurotoxic substances, and we evaluated whether testing for color vision impairment could be an affordable procedure for assessing these neurotoxic effects. In general, most cases of congenital color vision impairment are red-green, and blue-yellow impairment is extremely rare. However, most of the acquired color vision impairment that is related to age, alcohol or environmental factors is blue-yellow impairment. Therefore, many studies have been performed to identify this relationship between exposure to neurotoxic substances, such as organic solvents and heavy metals, and the prevalence of blueyellow color vision impairment. The test for color vision impairment is known to be very sensitive to the early signs of nervous system dysfunction and this can be useful for making the early diagnosis of neurotoxic effects from exposure to very low concentrations of toxic substances.
*Color Perception Tests ; Color Vision Defects/*chemically induced/diagnosis ; Early Diagnosis ; Hazardous Substances/*toxicity ; Humans ; Neurotoxicity Syndromes/*diagnosis/pathology ; Solvents/adverse effects

Silent mating type information regulation 2 homolog 1 (SIRT1) is a nicotinamide adenosine dinucleotide (NAD+)-dependent class III histone deacetylase and is distributed in central nervous system and peripheral tissue. SIRT1 interacts with various transcription factors and cofactors by histone deacetylation and is involved in the modulation of food intake, energy metabolism, circadian rhythms, learning and memory, neurogenesis and neuroprotection. Increased or decreased SIRT1 activity or levels by pharmacological treatment or in genetic animal models have demonstrated its function and role in Central Nervous System and peripheral tissue. Recent study suggests that dysregulation of SIRT1 may be involved in anxiety or depression, but relatively little is known about the involvement of SIRT1 in anxiety or depression. Therefore, through unraveling the functional role of SIRT1 in food intake, energy metabolism, learning and memory as well as neuropsychiatric disease, studies on SIRT1 can shed light on the new drug development in treating neurodegenerative disease, metabolic disorder and neuropsychiatric disorder.
Adenosine ; Anxiety ; Central Nervous System ; Circadian Rhythm ; Depression ; Eating ; Energy Metabolism ; Histone Deacetylases ; Histones ; Learning ; Light ; Memory ; Models, Animal ; Neurodegenerative Diseases ; Neurogenesis ; Niacinamide ; Sirtuin 1 ; Transcription Factors

OBJECTIVE: To investigate the stem cell-like characteristics of human periodontal ligament (PDL) stromal cells outgrown from orthodontically extracted premolars and to evaluate the potential for myogenic differentiation. METHODS: PDL stromal cells were obtained from extracted premolars by using the outgrowth method. Cell morphological features, self-replication capability, and the presence of cell-surface markers, along with osteogenic, adipogenic, and chondrogenic differentiation, were confirmed. In addition, myogenic differentiation was induced by the use of 5-aza-2'-deoxycytidine (5-Aza) for DNA demethylation. RESULTS: PDL stromal cells showed growth patterns and morphological features similar to those of fibroblasts. In contrast, the proliferation rates of premolar PDL stromal cells were similar to those of bone marrow and adipogenic stem cells. PDL stromal cells expressed surface markers of human mesenchymal stem cells (i.e., CD90 and CD105), but not those of hematopoietic stem cells (i.e., CD31 and CD34). PDL stromal cells were differentiated into osteogenic, adipogenic, and chondrogenic lineages. Myotube structures were induced in PDL stromal cells after 5-Aza pretreatment, but not in the absence of 5-Aza pretreatment. CONCLUSIONS: PDL stromal cells isolated from extracted premolars can potentially be a good source of postnatal stem cells for oromaxillofacial regeneration in bone and muscle.
Azacitidine ; Bicuspid ; Bone Marrow ; DNA ; Durapatite ; Fibroblasts ; Hematopoietic Stem Cells ; Humans ; Mesenchymal Stromal Cells ; Molecular Biology ; Muscle Fibers, Skeletal ; Muscles ; Periodontal Ligament ; Regeneration ; Stem Cells ; Stromal Cells

Programmed death-1 (PD-1) is a strong negative regulator of T lymphocytes in tumor-microenvironment. By engaging PD-1 ligand (PD-L1) on tumor cells, PD-1 on T cell surface inhibits anti-tumor reactivity of tumor-infiltrating T cells. Systemic blockade of PD-1 function using blocking antibodies has shown significant therapeutic efficacy in clinical trials. However, approximately 10 to 15% of treated patients exhibited serious autoimmune responses due to the activation of self-reactive lymphocytes. To achieve selective activation of tumor-specific T cells, we generated T cells expressing a dominant-negative deletion mutant of PD-1 (PD-1 decoy) via retroviral transduction. PD-1 decoy increased IFN-γ secretion of antigen-specific T cells in response to tumor cells expressing the cognate antigen. Adoptive transfer of PD-1 decoy-expressing T cells into tumor-bearing mice potentiated T cell-mediated tumor regression. Thus, T cell-specific blockade of PD-1 could be a useful strategy for enhancing both efficacy and safety of anti-tumor T cell therapy.
Adoptive Transfer ; Animals ; Antibodies, Blocking ; Autoimmunity ; Cell- and Tissue-Based Therapy ; Humans ; Lymphocytes ; Mice ; T-Lymphocytes ; T-Lymphocytes, Cytotoxic* ; Zidovudine

Chronic granulomatous infection of the skin and soft tissue by nontuberculous mycobacteria in patients with normal immune system is rarely reported. This case was about a child patient, with normal immune system, whose lower leg was lacerated after a slip down in the Philippines and it was previously treated at a hospital in the Philippines. After a couple of surgical debridement of the wound, the cause of the soft tissue infection was found to be a combined infection of nontuberculous mycobacteria and mycobacterium tuberculosis. We present a case that has been rare in Korea, but common overseas.
Child ; Debridement ; Humans ; Immune System ; Korea ; Leg ; Mycobacterium tuberculosis ; Nontuberculous Mycobacteria ; Philippines ; Skin ; Soft Tissue Infections

BACKGROUND: Emergence agitation after sevoflurane anesthesia in children can be prevented by midazolam. Alternative splicing of the GABAA receptor changes with age. Therefore, we hypothesized that alternative splicing of the gamma2 subunit affects the GABA current when applying sevoflurane and midazolam. METHODS: We performed the whole-cell patch clamp technique on human embryonic kidney 293 cells that were transfected with alpha1beta2gamma2L or alpha1beta2gamma2S. The concentration-response relations were recorded for midazolam and sevoflurane, and the co-application responses were measured at concentrations of 1.5 nM, 15 nM and 300 nM of midazolam and 0.5%, 2.0% and 4.0% of sevoflurane. Each GABA current was compared with that produced by 5 microM of GABA. RESULTS: The concentration-response relationships for midazolam and sevoflurane were dose-dependent without any differences between the alpha1beta2gamma2L and alpha1beta2gamma2S subtypes. 1.5 nM and 15 nM of midazolam did not significantly enhance the current after treatment with 0.5% sevoflurane for both subtypes. The current after treatment with 2.0% sevoflurane was enhanced by 1.5 nM midazolam for the alpha1beta2gamma2S subtype, but not for the alpha1beta2gamma2L subtype. In the case of 2.0% sevoflurane with 15 nM of midazolam, and 4.0% sevoflurane with 300 nM of midazolam, the GABA currents were significantly enhanced for both subtypes. CONCLUSIONS: These results show that the difference in the gamma2 subunit cannot explain the emergence agitation after sevoflurane anesthesia in children in vitro. This suggests that co-application of sevoflurane and midazolam enhances the GABA current according to the alternative splicing of the gamma2 subunit and the concentration of both drugs.
Alternative Splicing ; Anesthesia ; Child ; Dihydroergotamine ; gamma-Aminobutyric Acid ; Humans ; Kidney ; Methyl Ethers ; Midazolam

OBJECTIVES: Corticotropin releasing factor (CRF) plays a primary role in coordinating the neuroendocrine, autonomic, immune and behavioral responses to stress. CRF exerts its action through two major receptors, corticotropin-releasing factor 1 Receptor (CRF-R1) and corticotropin-releasing factor 2 receptor (CRF-R2). Using two types of chronic stress models, we investigated the changes of CRF-R1 mRNA and CRF-R2A mRNA expressions and CRF mRNA in the stress related brain circuit areas. METHODS: Male Sprague-Dawley rats were exposed to either immobilization stress or variable intermittent unpredictable stress for 10 days and then in situ hybridization histochemistry was used to quantify CRF expression in the brain. RESULTS: 1) CRF1 receptor mRNA expressions were decreased in bed nucleus stria terminalis (BNST) following stressors. 2) CRF2A receptor mRNA expressions were increased in lateral septum following stressors. 3) CRF mRNA expressions were increased in central nucleus of amygdala (CeA) and BNST. CONCLUSION: The increased CRF mRNA of CeA and BNST may be related with anxiety response in the repeated stress. Down-regulation of CRF-R1 mRNA expression in BNST may represent a compensatory adaptation to chronic stress and may be involved in the anxiety response, whereas up-regulation of CRF-R2A mRNA expression in lateral septum may represent an anxiety response or impaired learning but the functional meaning is uncertain.
Adrenocorticotropic Hormone* ; Amygdala ; Anxiety ; Brain ; Corticotropin-Releasing Hormone* ; Down-Regulation ; Humans ; Immobilization ; In Situ Hybridization ; Learning ; Male ; Rats, Sprague-Dawley ; Receptors, Corticotropin-Releasing Hormone ; RNA, Messenger ; Up-Regulation

Gamma 3 rotation control lag screws (U-blade) are particularly useful when treating rotational and unstable fractures of the proximal femur. A 93-year-old woman who underwent closed reduction of a trochanteric fracture and internal fixation with a Gamma 3 nail rotation control lag screw. The patient presented with metal failure and U-blade bending following a fall occurring 4 weeks after surgery. Here, we present a case report summarizing removal of the failed lag screw.
Female ; Femur ; Humans

BACKGROUND/OBJECTIVES: The diet is an important route of exposure to endocrinedisrupting chemicals (EDCs). However, few studies have investigated the association between dietary intake and EDC exposure levels among Koreans. In an earlier study, we showed that the bioactivity of serum aryl hydrocarbon receptor ligands (AhRLs) could be a surrogate biomarker to indicate exposure to EDCs and that they inhibit mitochondrial function. We also found that the mitochondria-inhibiting substances (MIS) in serum ascertained by intracellular adenosine triphosphate (MIS-ATP) and reactive oxygen species (MIS-ROS) levels could be biomarkers of exposure to EDCs, as they showed a strong correlation with AhRL and the levels of EDCs in the blood. Here, we investigated the association between the consumption of specific foods and surrogate serum biomarkers for EDCs, namely AhRL, MIS-ATP, and MIS-ROS, among middle-aged Korean adults. SUBJECTS/METHODS: A total of 1,466 participants aged 45–76 yrs from the Ansung cohort of the Korean Genome and Epidemiology Study were included. Food consumption, including that of meat, fish, vegetables, and fruits, was measured using a semiquantitative food frequency questionnaire. RESULTS: Fish intake was positively associated with AhRL (β = 0.0035, P = 0.0166), whereas cruciferous vegetable intake was negatively associated with AhRL (β = −0.0007, P = 0.0488).Cruciferous vegetable intake was positively associated with the MIS-ATP levels (β = 0.0051, P = 0.0420). A higher intake of fish was significantly associated with an increased risk of high AhRL (tertile: odds ratio [OR], 1.49; 95% confidence intervals (CIs), 1.08–2.06; P for trend = 0.0305). In addition, the second-highest tertile of cruciferous vegetable intake had lower odds of high AhRL than the lowest tertile (OR, 0.73; 95% CIs, 0.54–0.97), although no significant linear trend was observed. CONCLUSION Consumption of different types of foods may be differentially associated with EDC exposure in middle-aged Korean adults.