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The slow and regular pacemaking activity of midbrain dopamine (DA) neurons requires proper spatial organization of the excitable elements between the soma and dendritic compartments, but the somatodendritic organization is not clear. Here, we show that the dynamic interaction between the soma and multiple proximal dendritic compartments (PDCs) generates the slow pacemaking activity in DA neurons. In multipolar DA neurons, spontaneous action potentials (sAPs) consistently originate from the axon-bearing dendrite. However, when the axon initial segment was disabled, sAPs emerge randomly from various primary PDCs, indicating that multiple PDCs drive pacemaking. Ca2+ measurements and local stimulation/perturbation experiments suggest that the soma serves as a stably-oscillating inertial compartment, while multiple PDCs exhibit stochastic fluctuations and high excitability. Despite the stochastic and excitable nature of PDCs, their activities are balanced by the large centrally-connected inertial soma, resulting in the slow synchronized pacemaking rhythm. Furthermore, our electrophysiological experiments indicate that the soma and PDCs, with distinct characteristics, play different roles in glutamate-induced burst-pause firing patterns. Excitable PDCs mediate excitatory burst responses to glutamate, while the large inertial soma determines inhibitory pause responses to glutamate. Therefore, we could conclude that this somatodendritic organization serves as a common foundation for both pacemaker activity and evoked firing patterns in midbrain DA neurons. [ABSTRACT FROM AUTHOR]

Purpose: The coronavirus disease 2019 (COVID-19) pandemic has affected people's daily lives and increased their time spent at home. This study aims to investigate the changes in lifestyle factors and obesity among Korean adolescents before and during the COVID-19 outbreak. Methods: We used the data of 109,282 adolescents aged 12-18 years, from the Korea Youth Risk Behavior Survey conducted in 2019 and 2020 before and during the COVID-19 pandemic, respectively. The changes in the prevalence of obesity and lifestyle factors (diet, exercise, sitting time, and sleep duration) were assessed. The adjusted odds ratios (ORs) (95% confidence intervals [CIs]) of predictors for obesity were calculated. Results: The prevalence of overweight (10% to 10.5%) and obesity (11.5% to 12.7%) increased significantly, especially among males younger than 15 years, whereas significant differences were absent among females. The mean body mass index z-score increased from 0.28 to 0.39 in males but decreased from 0.08 to 0.04 in females. Fruit consumption, regular exercise, and average sleep duration decreased, whereas sitting time increased. After controlling for covariates, a short sleep duration (OR, 1.14) and an increased sitting time (OR, 1.14) were significantly associated with an elevated risk for overweight/obesity. Conclusion: During the COVID-19 pandemic, the prevalence of obesity and overweight increased, particularly in males, as did unfavorable trends in related lifestyle factors. Sex- and age-specific strategies to improve lifestyle factors associated with obesity are needed, especially during the COVID-19 pandemic. [ABSTRACT FROM AUTHOR]

Background/Aims Platelet-derived growth factor receptor alpha-positive (PDGFRá+) cells function in the purinergic regulation of gastrointestinal motility, and purines are reportedly inhibitory neurotransmitters in the enteric nervous system. We explore the distribution and function of PDGFRá+ cells related to purinergic inhibitory neurotransmission in human right and left colons. Methods Human colonic segments were prepared with mucosa and submucosa intact, and the circular muscle tension and longitudinal muscle tension were recorded. Purinergic neurotransmitters were administered after recording the regular contractions. Immunohistochemistry was performed on the circular muscle layers. Intracellular recording was performed on the colonic muscular layer. SK3, P2RY1, and PDGFR-á mRNA expression was tested by quantitative real-time polymerase chain reaction (qPCR). Results Adenosine triphosphate (ATP) treatment significantly decreased the frequency and area under the curve (AUC) of the segmental contraction in right and left colons. Beta-nicotinamide adenine dinucleotide (â-NAD) decreased the frequency in the right colon and the amplitude, frequency and AUC in the left colon. Apamin significantly increased frequency and AUC in the left colon, and after apamin pretreatment, ATP and â-NAD did not change segmental contractility. Through intracellular recordings, a resting membrane potential decrease occurred after ATP administration; however, the degree of decrease between the right and left colon was not different. PDGFRá+ cells were distributed evenly in the circular muscle layers of right and left colons. SK3, P2RY1, and PDGFRá expression was not different between the right and left colon. Conclusion Purines reduce right and left colon contractility similarly, and purinergic inhibitory neurotransmission can be regulated by PDGFRá+ cells in the human colon. [ABSTRACT FROM AUTHOR]

Background: Phthalates and bisphenol A (BPA) are synthetic chemicals widely used in daily life. This study investigated urinary phthalate and BPA levels in Korean children and their associations with obesity. Methods: A total of 2,351 children aged 3 to 17 years who participated in the Korean National Environmental Health Survey 2015 to 2017 were included. Urinary dilution was corrected using covariate-adjusted standardization (CAS). We examined the geometric mean (GM) concentrations of urinary phthalate metabolites, including di (2-ethylhexyl) phthalate (DEHP) metabolites (mono [2-ethyl- 5-hydroxyhexyl] phthalate, mono [2-ethyl-5-oxohexyl] phthalate, and mono [2-ethyl-5-carboxypentyl] phthalate [MECPP]), mono- benzyl-phthalate (MBzP), mono (carboxyoctyl) phthalate (MCOP), mono (carboxy-isononyl) phthalate (MCNP), mono (3-carboxypropyl) phthalate, and mono-n-butyl-phthalate (MnBP), and BPA. We also analyzed the odds ratio (OR) for obesity according to the quartiles of each analyte. Results: The urinary GM levels of DEHP metabolites and MnBP were notably higher among Korean children than among American, Canadian, and German children. The CAS-applied GM concentrations of most analytes, except for MBzP, MCOP, and MCNP, were higher in children aged 3 to 5 years than in those aged 6 to 17 years. The OR for obesity in the highest quartile of MECPP was significantly higher than in the lowest quartile after adjusting for covariates. However, the other phthalate metabolites and BPA were not significantly associated with obesity. Conclusion: The concentrations of urinary DEHP metabolites and MnBP were higher in Korean children than in children in Western countries. Urinary MECPP exposure, but not other phthalates or BPA, showed a positive association with obesity in Korean children. Further studies are required to elucidate the causal relationships. [ABSTRACT FROM AUTHOR]

Background: There is a lack of recent research on the changes in risk factors for metabolic syndrome (MetS) in the Asian pediatric population. We aimed to determine the 12-year trends in the prevalence of MetS and relevant lifestyle factors such as smoking, exercise, and calorie intake among Korean adolescents. Methods: We investigated trends in MetS and lifestyle factors among 6,308 adolescents aged 12 to 18 years from the Korea National Health and Nutrition Examination Survey, 2007 to 2018. Results: The prevalence of MetS was stable from 2007 to 2018 (1.7% to 2.2%). There were significant increases in the prevalence of central obesity (from 8.1% to 11.2%, P=0.012) and hyperglycemia (from 5.3% to 10.4%, P<0.001) and decreases in hypo-highdensity lipoprotein (HDL)-cholesterolemia (from 22.4% to 14.8%, P<0.001). Total calorie intake and calorie intake from fat significantly increased (P<0.001), whereas calorie intake from carbohydrates significantly decreased (P<0.001) during the study period. The proportions of tobacco smokers and regular walkers significantly decreased from 2007 to 2018. After controlling for all covariates, total calorie intake was positively correlated with waist circumference (P<0.05). HDL-cholesterol was negatively associated with carbohydrate consumption (P<0.01) and positively associated with fat consumption (P<0.001). Regular walking and regular strength training were associated with lower waist circumference (P<0.05). Smoking was associated with lower fasting glucose levels (P<0.01). Conclusion: Although the prevalence rate of MetS is stable among Korean adolescents, the prevalence of central obesity and hyperglycemia has increased greatly in the recent decade. Public education on proper dietary intake and lifestyle modification is required. [ABSTRACT FROM AUTHOR]

Purpose: This study sought to identify changes in anthropometric values among Korean school students by comparing the most recent nationwide data with previous data. Methods: Data from the Korea School Health Examination Survey 2018 were used. The study population consisted of 107,954 Korean school students ranging from the 1st grade in elementary school through the 3rd year of high school. The difference in height and weight values for each sex and school grade was analyzed by comparison with the Korea School Health Examination Survey 2010. Results: The mean heights of the 3rd-year high school students were 173.8 cm and 160.9 cm for boys and girls, respectively. The mean height of the 3rd-year high school students showed no difference between 2010 and 2018 for either sex. However, the mean height of the age group from the 3rd grade in elementary school through the 1st year in high school was significantly taller in 2018 compared to 2010 for both sexes. The mean weights of the 3rd-year high school students were 71.3 kg and 57.5 kg for boys and girls, respectively. The mean weight of students in 2018 was significantly higher compared to students in 2010 for most school grades. Conclusion: Although no significant change was found in near-final height between 2010 and 2018 among high school seniors, the mean height during the growth spurt was significantly higher in 2018 compared to 2010. Weight was significantly higher in almost all school grades in 2018 compared to 2010. [ABSTRACT FROM AUTHOR]

Childhood obesity is a global health concern. Air pollution is also a crucial health threat, especially in developing countries. Over the past decade, a number of epidemiologic and animal studies have suggested a possible role of pre- or postnatal exposure to air pollutants on childhood obesity. Although no clear mechanism has been elucidated, physical inactivity, oxidative stress, and epigenetic modifications have been suggested as possible mechanisms by which obesity develops due to air pollution. In this review, we summarize and review previous epidemiologic studies linking air pollution and childhood obesity and discuss the possible mechanisms underlying air pollution-induced obesity based on in vivo and in vitro evidence. [ABSTRACT FROM AUTHOR]

Purpose: This study was conducted to investigate the distributions of the triglyceride (TG) to high-density lipoprotein-cholesterol (HDL-C) ratio and total cholesterol (TC) to HDL-C ratio, and to explore their usefulness as markers of metabolic syndrome (MetS) in Korean adolescents. Methods: We obtained data for 2,721 adolescents (1,436 boys and 1,285 girls) aged 10-18 years who participated in the Korean National Health and Nutrition Examination Surveys from 2008 to 2010. International Diabetes Federation criteria were used to define MetS. Results: : There were no significant gender-related differences in TG/HDL-C or TC/ HDL-C ratios. These lipid ratios showed significant associations with homeostatic model assessment for insulin resistance (HOMA-IR) and waist circumference. Areas under the receiver operating characteristic curve to identify MetS were 0.947 for TG/HDL-C and 0.924 for TC/HDL-C, which were higher than that of HOMA-IR (0.822). Optimal cutoff values (sensitivity, specificity) of TG/HDL-C and TC/HDL-C ratios for MetS prediction were 3.3 (85.7%, 89.9%), and 3.8 (92.9%, 82.8%), respectively. Odds ratio (OR; 95% confidence intervals [CIs]) for MetS in adolescents with TC/HDL-C ratio above the cutoff value was 14.8 (2.8-77.4), while that for TG/HDL-C ratio about the cutoff value was 30.6 (6.0-157.6). In adolescents who had both lipid ratios above the cutoff values, the OR (95% CI) for MetS was 36.2 (7.2-186.2). Conclusion: TG/HDL-C and TC/HDL-C ratios are useful markers of metabolic syndrome with high predictive value in Korean adolescents. [ABSTRACT FROM AUTHOR]

Tympanometric volume is a useful tool for evaluating middle ear status in otitis media. However, its usefulness in chronic otitis media (COM) has not been well evaluated. This study aimed to investigate whether tympanometric volume reflects the status of the middle ear and mastoid or can provide clinical information about patients with COM and subsequent tympanic membrane perforation. A prospective cohort study including 50 adult patients with COM and subsequent tympanic membrane perforation was performed. The volumes of the middle ear and mastoid were preoperatively calculated using tympanometry and three-dimensional computed tomography (CT) reconstruction of the temporal bone, respectively. During surgery for COM, the patency of the middle ear and mastoid antrum was evaluated. The volumes of the middle ear and mastoid measured by tympanometry and CT were compared with the surgical findings. When the mastoid antrum was patent, the volumes of the middle ear and mastoid measured by tympanometry and CT were well correlated. Moreover, the difference in the volumes measured by tympanometry between the affected and unaffected ears was large. However, when the mastoid antrum was poorly aerated, the difference in the volumes measured by tympanometry between the affected and unaffected ears was small. Middle ear status can be evaluated according to the difference in tympanometric volume between the two ears. If the tympanometric volume suggests poor aeration of the middle ear and mastoid, clinicians should consider procedures for mastoid aeration. [ABSTRACT FROM AUTHOR]

Purpose: Obesity has been associated with higher total blood mercury levels, based on animal studies; however, studies that focus on children and adolescents are lacking. We aimed to assess the association between total blood mercury levels and the incidence of overweight and abdominal obesity in Korean adolescents. Methods: The study population comprised 1,567 adolescents (793 boys and 774 girls; aged 10-19 years), who participated in the Korea National Health and Nutrition Examination Survey 2010-2013. We analyzed total blood mercury levels according to obesity status in all participants. Results: The geometric mean of total blood mercury levels was 1.93 µg/L. Participants with overweight (2.20 µg/L) and obesity (2.17 µg/L) had higher levels than those with normal weight (1.86 µg/L, P<0.0001). The prevalence of overweight significantly increased with elevation of the total blood mercury quartile in both sexes. Increased incidence of abdominal obesity corresponding to increased total blood mercury level was observed in boys. After adjusting for covariates, those in the highest total blood mercury quartile were found to be at higher risk of overweight/obesity than those in the lowest quartile in both sexes (odds ratio [95% confidence interval]: boys, 3.27 [1.66-6.41]; girls, 1.90 [1.03-3.49]). The association between total blood mercury quartile and abdominal obesity was significant after controlling for covariates in boys (2.35 [1.05-5.24]). Conclusion: Our results suggest an association between total blood mercury levels and overweight in Korean adolescents. [ABSTRACT FROM AUTHOR]

Background: Streptococcus pneumoniae colonize the human nasopharynx in the form of biofilms. The biofilms act as bacterial reservoirs and planktonic bacteria from these biofilms can migrate to other sterile anatomical sites to cause pneumonia, otitis media (OM), bacteremia and meningitis. Human amniotic membrane contains numerous growth factors and antimicrobial activity; however, these have not been studied in detail. In this study, we prepared amniotic membrane extract and chorionic membrane extract (AME/CME) and evaluated their antibacterial and antibiofilm activities against S. pneumoniae using an in vitro biofilm model and in vivo OM rat model. Materials and Methods: The AME/CME were prepared and protein was quantified using DCTM (detergent compatible) method. The minimum inhibitory concentrations were determined using broth dilution method, and the synergistic effect of AME/CME with Penicillin-streptomycin was detected checkerboard. The in vitro biofilm and in vivo colonization of S. pneumoniae were studied using microtiter plate assay and OM rat model, respectively. The AME/CME-treated biofilms were examined using scanning electron microscope and confocal microscopy. To examine the constituents of AME/CME, we determined the proteins and peptides of AME/CME using tandem mass tag-based quantitative mass spectrometry. Results: AME/CME treatment significantly (p < 0.05) inhibited S. pneumoniae growth in planktonic form and in biofilms. Combined application of AME/CME and Penicillin-streptomycin solution had a synergistic effect against S. pneumoniae. Biofilms grown with AME/CME were thin, scattered, and unorganized. AME/CME effectively eradicated pre-established pneumococci biofilms and has a bactericidal effect. AME treatment significantly (p < 0.05) reduced bacterial colonization in the rat middle ear. The proteomics analysis revealed that the AME/CME contains hydrolase, ribonuclease, protease, and other antimicrobial proteins and peptides. Conclusion: AME/CME inhibits S. pneumoniae growth in the planktonic and biofilm states via its antimicrobial proteins and peptides. AME/CME are non-cytotoxic, natural human product; therefore, they may be used alone or with antibiotics to treat S. pneumoniae infections. [ABSTRACT FROM AUTHOR]

Growth hormone (GH) is important for promotion of somatic growth and the regulation of substrate metabolism. Metabolic action of GH occurs in multiple tissues including the liver, muscle, fat and pancreas either directly or indirectly through insulin-like growth factor 1. The diabetogenic action of GH has been well-described in previous in vivo studies. In this paper, we review the metabolic effects of GH on peripheral tissues focusing on glucose metabolism and insulin resistance, and discuss results from human studies on the long-term effects of GH administration on insulin resistance and hyperglycemia. [ABSTRACT FROM AUTHOR]

Childhood obesity increases the risk of morbidity and mortality in adulthood. The epidemic of childhood obesity has become an important public health issue in Korea. Currently, the overall prevalence of obesity among Korean children and adolescents is approximately 10%, which is 5 times higher than in the late 1970s. In most cases, a positive energy balance (from excessive calorie intake and limited physical activity) combined with a genetic predisposition is considered the major cause of childhood obesity. The evaluation of obese children should focus on possible causes of weight gain, including lifestyle factors and underlying endocrine or genetic abnormalities. The assessment of obesityrelated comorbidities, such as hyperglycemia, dyslipidemia, hypertension, and non-alcoholic fatty liver disease, is often needed in obese children, especially those who have a family history of comorbidities. Family-based lifestyle interventions including goal-setting, guidelines for eating habits and physical activity, self-monitoring, and stimulus control are fundamental to the management of childhood obesity. Medications and bariatric surgery are possible choices for patients with severe obesity and comorbidities, although the data on the long-term efficacy and safety of these treatments are limited. This article reviews practical assessments and interventions for childhood obesity. [ABSTRACT FROM AUTHOR]

Lipid profiling in nine bacterial species has been accomplished by laser desorption ionization mass spectrometry (LDI-MS) using amorphous silicon (a-Si) thin film with 100 nm thickness. Lipid ions could be generated by LDI on a-Si regardless of ion acquisition modes because of a thermal property of a-Si to govern laser-induced surface heating. In a comparative study of lipid profiling in Bacillus lichemiformis by LDI-MS and matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS), LDI-MS on a-Si shows a higher efficiency in lipid and lipopeptide detection than MALDI-MS. A total of 53 peaks of lipid ions generated by LDI on a-Si in both acquisition modes for m/z 400-1200 was 1.6 times more than that detected by MALDI-MS using three organic matrices--2,5-dihydroxybenzoic acid, 1,5-diaminonaphthalene, and 2,4,6-trihydroxyacetophenone monohydrate. Also, the authors demonstrate by mass spectrometry imaging (MSI) that LDI-MS provides high detection coverage through whole sample area. MSI results show the detection yield in LDI on a-Si is 94.8% calculated by counting the number of points detected in the analyte ion signal in a whole spot. It means that reproducible detection of lipid ions by LDI-MS is possible even if laser is randomly irradiated at any position within the bacterial sample area applied on a-Si. Lipid profiling by LDI-MS on a-Si was applied to bacterial differentiation of nine bacterial species conducted by performing principal component analysis. Nine bacterial species are successfully distinguishable from each other by LDI-MS lipid profiling. [ABSTRACT FROM AUTHOR]

Background: An increased incidence of central precocious puberty has been recently reported in South Korea, which suggests an ongoing downward trend in pubertal development in the Korean population. We aimed to verify the trend in age at menarche in young Korean women during the last decade and associated factors. Methods: We analyzed a population-based sample of 3409 Korean girls, aged 10-18 years, using data from the Korean National Health and Nutrition Examination Surveys (KNHANES) II (2001), III (2005), IV (2007-2009), and V (2010 and 2011). Average age at menarche was studied using the Kaplan-Meier survival method and predictors were analyzed using Cox proportional hazards model. The percentage of subjects who had experienced menarche at each age level was compared by using the Cochran-Armitage test. Results: Overall mean age at menarche was 12.7 years. The percentage of subjects who experienced menarche before the age of 12 years was 21.4 % in 2001 but increased to 34.6 % in 2010/2011 (p < 0.01). In addition, the percentage of girls who experienced menarche before the age of 14 years increased from 76 % in 2001 to 92 % in 2010/2011 (p < 0.005). Adolescents whose mothers who had experienced early menarche (HR 1.48, 95 % CI [1.22-1.80]), and adolescents who were overweight (HR 1.24, 95 % CI [1.04-1.49]) were more likely to have experienced menarche. Additionally, underweight adolescents (HR 0.27, 95 % CI [0.12-0.60]) and adolescents who had a mother having late menarche (HR 0.68, 95 % CI [0.59-0.79]) were expected to have late menarche. None of the socioeconomic factors assessed in our study showed an association with age at menarche. Conclusions: A downward trend in age at menarche was defined in Korean adolescents during the last decade. Furthermore, influences of genetic and nutritional parameters on individual variance in age at menarche were defined. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to assess the reference values and factors influencing blood lead levels among Korean adolescents. Methods: The study population consisted of 1,585 adolescents (801 males, 784 females; aged 10-19 years) who participated in the Korea National Health and Nutrition Examination Survey 2010- 2013. We analyzed blood lead concentrations in relation to demographic/lifestyle characteristics for all participants. "Reference values" of blood lead levels were calculated as the upper limit of the 95% confidence interval of the 95th percentile. Results: The average "reference value" for blood lead concentrations among Korean adolescents was 2.25 μg/dL (2.49 μg/dL for males, 2.07 μg/dL for females), and the geometric mean of the blood lead concentrations was 1.34 μg/dL. Males had higher blood lead concentrations than females (male, 1.48 μg/dL; female, 1.19 μg/dL; P<0.001). Elementary school students had higher blood lead concentrations than junior and senior high school students (1.44 μg/dL vs. 1.31 μg/dL, P<0.001). Participants living in detached houses had higher blood lead concentrations than those living in apartments (P<0.001) and current smokers had higher concentrations than nonsmokers or participants with secondhand smoke exposure (P<0.05). Additionally, participants with excessive alcohol consumption had higher levels than non-drinkers (P<0.001). Conclusion: This study provides national reference data on blood lead concentrations stratified by demographic and lifestyle factors among Korean adolescents. Further studies are needed to elucidate the relationship between increased lead exposure and demographic factors including type of housing. [ABSTRACT FROM AUTHOR]

Purpose: Only a few studies have explored nationwide trends in lipid profiles among Asian adolescents. We aimed to assess trends in lipid profiles and the associated lifestyle factors among Korean children. Methods: We analyzed data for 2,094 adolescents who were aged 10-18 years and had participated in the Korea National Health and Nutrition Examination Surveys in 1998 and 2010. Results: During 1998-2010, the prevalence of obesity significantly increased in boys, but no changes were observed in girls. Over this period, there was a small but significant decrease in the mean lowdensity lipoprotein (LDL)-cholesterol level in boys (1998, 87.5 mg/dL; 2010, 83.6 mg/dL; P=0.019) and mean triglyceride levels in girls (1998, 90.8 mg/dL; 2010, 85.8 mg/dL; P=0.020). There were no significant changes in the prevalence of dyslipidemia in boys, but a modest decrease was noted in girls (1998, 25.1%; 2010, 18.3%; P=0.052). During the study period, the prevalence of breakfast skipping decreased, whereas that of regular exercise increased in both groups. Daily total energy intake did not change between these years. In multivariable logistic regression analyses, breakfast skipping was associated with increased risk of hyper-LDL-cholesterolemia in boys (odds ratio [OR], 5.77) and hypertriglyceridemia (OR, 2.27) in girls. Regular exercise was associated with decreased risk of hypo-HDL-cholesterolemia (OR, 0.40) in boys. Conclusion: Although the prevalence of obesity in boys increased, favorable or constant trends in lipid profiles were observed among Korean adolescents during 1998-2010. Decrease in breakfast skipping and increase in regular exercise may have contributed to these trends. [ABSTRACT FROM AUTHOR]

Chronic inflammatory demyelinating polyneuropathy (CIDP) is a chronically progressive or relapsing symmetric sensorimotor disorder presumed to occur because of immunologic antibody-mediated reactions. To understand the clinical courses of CIDP, we report variable CIDP courses in children with respect to initial presentation, responsiveness to medical treatment, and recurrence interval. Four patients who were diagnosed with acute-onset and relapsing CIDP courses at Severance Children's Hospital, Seoul, Korea, were enrolled in this retrospective study. We diagnosed each patient on the basis of the CIDP diagnostic criteria developed in 2010 by the European Federation of Neurological Societies/Peripheral Nerve Society Guidelines. We present the cases of four pediatric patients diagnosed with CIDP to understand the variable clinical course of the disease in children. Our four patients were all between 8 and 12 years of age. Patients 1 and 2 were diagnosed with acute cerebellar ataxia or Guillain-Barré syndrome as initial symptoms. While patients 1 and 4 were given only intravenous dexamethasone (0.3 mg/kg/day) for 5 days at the first episode, Patients 2 and 3 were given a combination of intravenous immunoglobulin (2 g/kg) and dexamethasone (0.3 mg/kg/day). All patients were maintained with oral prednisolone at 30 mg/day, but their clinical courses were variable in both relapse intervals and severity. We experienced variable clinical courses of CIDP in children with respect to initial presentation, responsiveness to medical treatment, and recurrence interval. [ABSTRACT FROM AUTHOR]

Phthalates are commonly used as plasticizers and vehicles for cosmetic ingredients. Phthalate metabolites have documented biochemical activity including activating peroxisome proliferator-activated receptor and antiandrogenic effects, which may contribute to the development of obesity. In vitro and in vivo studies suggest that phthalates have significant effects on the development of obesity, especially after prenatal exposure at low doses. Although few studies have examined the effects of phthalate on obesity development in humans, some work has shown that phthalates affect humans and animals similarly. In this paper, we review the possible mechanisms of phthalate-induced obesity, and discuss evidence supporting the role of phthalates in the development of obesity in humans. [ABSTRACT FROM AUTHOR]

Background: The aim of this study is to investigate the distribution of plasma cholesterol and triglyceride levels as well as the prevalence of dyslipidemia among Korean adolescents. Methods: We analyzed data for 3,045 adolescents aged 10-18 years (1,622 boys and 1,423 girls) who participated in the Korea National Health and Nutrition Examination Surveys from 2007 to 2010. Results: The mean values of total cholesterol, triglycerides, low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C) were 159, 89, 89, and 52 mg/dL, respectively. Plasma cholesterol levels were significantly higher in girls than those in boys (162.1 mg/dL vs. 155.6 mg/dL, P < 0.0001). The 90th percentile values of total cholesterol, triglycerides, and LDLC were 192, 149, 117 mg/dL for boys, and 195, 147, 119 mg/dL for girls. The 10th percentile value of HDL-C was 38 mg/dL for boys and 40 mg/dL for girls. Triglyceride, LDL-C cholesterol levels increased, whereas plasma HDL-C levels decreased with increasing the body mass index (P < 0.0001) in both genders. Total cholesterol levels significantly increased with increasing the body mass index, especially in boys (P < 0.0001). The prevalence of dyslipidemia was 25.2% for boys and 21.7% for girls; this value significantly increased with overweight (37-40%) and obesity (53-56%). Independent predictors (odds ratio) of dyslipidemia were age (1.49), overweight (2.06), and obesity (5.11) for boys; overweight (1.95) and obesity (3.22) for girls. Conclusion: Adolescent dyslipidemia is strongly associated with obesity. Lipid screening for overweight or obese youths should be emphasized. Further, longitudinal studies examining the impact of childhood obesity and dyslipidemia on subsequent cardiovascular diseases are needed. [ABSTRACT FROM AUTHOR]

Vascular smooth muscle cells can obtain a proliferative function in environments such as atherosclerosis in vivo or primary culture in vitro. Proliferation of vascular smooth muscle cells is accompanied by changes in ryanodine receptors (RyRs). In several studies, the cytosolic Ca2+ response to caffeine is decreased during smooth muscle cell culture. Although caffeine is commonly used to investigate RyR function because it is difficult to measure Ca2+ release from the sarcoplasmic reticulum (SR) directly, caffeine has additional off-target effects, including blocking inositol trisphosphate receptors and store-operated Ca2+ entry. Using freshly dissociated rat aortic smooth muscle cells (RASMCs) and cultured RASMCs, we sought to provide direct evidence for the operation of RyRs through the Ca2+- induced Ca2+ -release pathway by directly measuring Ca2+ release from SR in permeabilized cells. An additional goal was to elucidate alterations of RyRs that occurred during culture. Perfusion of permeabilized, freshly dissociated RASMCs with Ca2+ stimulated Ca2+ release from the SR. Caffeine and ryanodine also induced Ca2+ release from the SR in dissociated RASMCs. In contrast, ryanodine, caffeine and Ca2+ failed to trigger Ca2+ release in cultured RASMCs. These results are consistent with results obtained by immunocytochemistry, which showed that RyRs were expressed in dissociated RASMCs, but not in cultured RASMCs. This study is the first to demonstrate Ca2+ release from the SR by cytosolic Ca2+ elevation in vascular smooth muscle cells, and also supports previous studies on the alterations of RyRs in vascular smooth muscle cells associated with culture. [ABSTRACT FROM AUTHOR]

Dopamine (DA) receptors generate many cellular signals and play various roles in locomotion, motivation, hormone production, and drug abuse. According to the location and expression types of the receptors in the brain, DA signals act in either stimulatory or inhibitory manners. Although DA autoreceptors in the substantia nigra pars compacta are known to regulate firing activity, the exact expression patterns and roles of DA autoreceptor types on the firing activity are highly debated. Therefore, we performed individual correlation studies between firing activity and receptor expression patterns using acutely isolated rat substantia nigra pars compacta DA neurons. When we performed single-cell RT-PCR experiments, D1, D2S, D2L, D3, and D5 receptor mRNA were heterogeneously expressed in the order of D2L > D2S > D3 > D5 > D1. Stimulation of D2 receptors with quinpirole suppressed spontaneous firing similarly among all neurons expressing mRNA solely for D2S, D2L, or D3 receptors. However, quinpirole most strongly suppressed spontaneous firing in the neurons expressing mRNA for both D2 and D3 receptors. These data suggest that D2S, D2L, and D3 receptors are able to equally suppress firing activity, but that D2 and D3 receptors synergistically suppress firing. This diversity in DA autoreceptors could explain the various actions of DA in the brain. [ABSTRACT FROM AUTHOR]

The excitatory neurotransmitter, glutamate, generates a characteristic burst-pause type of firing in midbrain dopamine neurons in association with the reward behavior, but the cellular mechanism by which glutamate generates these bursts is unknown. Here, we show that the bursts in spontaneously firing dopamine neurons can be generated by the combinative actions of the brief stimulatory and the subsequent Ca2+-dependent inhibitory signals in response to glutamate stimulation. The two Ca2+-dependent firing-extinction signals are activated by different glutamate receptors. Although the activation of metabotropic glutamate receptors rapidly stopped the enhanced firing through the Ca2+ release from intracellular stores, the activation of NMDA and AMPA/kainate receptors abolished the firing immediately after termination of the stimulation due to the Ca2+ accumulation in the cell. These two Ca2+-dependent inhibitory mechanisms appear to participate in the generation of characteristic bursts in dopamine neurons by controlling the maximum firing number of single bursts and the duration of post-firing pauses. [ABSTRACT FROM AUTHOR]

Examines the glutamate-mediated (Ca[sup2+])[sub2] dynamics in spontaneously firing dopamine neurons of the rat substantia nigra pars compacta. Measurement of the spontaneously occurring action potentials; Identification of tetrodotoxin-sensitive spontaneous firing of 2-3 Hz; Activation of different glutamate receptors.

Objectives: The cervical vestibular evoked myogenic potentials (cVEMPs) require tonic sternocleidomastoid (SCM) recruitment, often achieved through an uncomfortaole head position. Here, we aimed to analyze the splenius capitis (SC) as a new target for cVEMPs. Material and methods: cVEMPs were recorded from both SCM and SC in 5 healthy male subjects (43.6±4.7 years) with two head positions (45° and 90° turned). For all subjects, computed tomography of neck was performed and the volumes of SCM and SC were calculated. Results: Clear cVEMPs were observed at 45° and 90° for SC, while only 90° for SCM. P1-N1 interamplitudes were smaller in SC (119.5± 138.6) than SCM (246.8±179.1 uV). There was no significant difference between SCM (39.8+4.9) and SC volumes (38.5±9.9 mm3). Conclusions: Adequate tonic SCM contraction could not be acnievable in some clinical situations. This study showed that SC with simple head-turned postures can be a new target of cVEMPs with moderate levels of muscle activation even in children and the elderly. [ABSTRACT FROM AUTHOR]

An abstract of the study "Serum Bisphenol A Levels in Girls With Central Precocious Puberty" by Shin Hye Kim et al is presented.

The endoplasmic reticulum (ER) Ca2+ store plays a key role in integration and conveyance of Ca2+ signals in highly polarized neurons. The interconnected ER network in neurons generates Ca2+ signals in local domains, but the regional interaction is unclear. Here, we show that continuous or repetitive applications of caffeine produced robust Ca2+ release from the ER Ca2+ store in dendritic areas without severe store depletion, but that similar stimuli applied to soma caused rapid store depletion in acutely isolated midbrain dopamine neurons. Partial emptying of the ER Ca2+ store within a dendrite caused a similar level of store depletion in unstimulated dendrites, as well as in soma. Photobleaching and local stimulation experiments revealed that Ca2+ and the dye trapped within the ER diffused rapidly from the soma to dendrites up to 90μm, which we could resolve, suggesting that the ER network acts as a functional tunnel for rapid Ca2+ transport. These data imply that the ER in soma acts as a Ca2+ reservoir supplying Ca2+ to the dendritic store, and that the dendritic store, hence, is able to respond to Ca2+-mobilizing input signals endurably. [ABSTRACT FROM AUTHOR]