Effects of chemical composition of ambient PM2.5 measured in Seoul on potential health risks and generation of reactive oxygen species.

This study assesses the health effects associated with the chemical species of ambient particulate matter (PM) with an aerodynamic diameter ≤2.5 µm (PM2.5) in Seoul, focusing on identifying key chemical constituents and their sources. We employed two approaches to estimate health risks: (1) evaluating carcinogenic and noncarcinogenic risks using IRIS (Integrated Risk Information System) data from the US EPA (Environmental Protection Agency), and (2) quantifying the generation of hydroxyl radicals (·OH) following exposure to PM2.5 in surrogate lung fluid (SLF). Our results show a significant impact on human health from certain elements (Cr, Ni, As, and Cd) and polycyclic aromatic hydrocarbons (PAHs) (DaeP, DahA, and BaP for carcinogenic risks; BaP and BeP for noncarcinogenic risks). Notably, Cr and BaP, which are influential in both risk assessment and ·OH generation, highlight their significant roles in human health impacts. However, other components (e.g., CPP, BaP, BghiP, BaA, CHR, PYR, FLT, Ca, Mg, and Cu), though contributors to ·OH generation, were not included in the EPA's health risk assessment, suggesting a need for a broader PM2.5 compositional analysis to more accurately determine exposure concentrations and assess inhalation risks. These components predominantly originate from anthropogenic sources, such as combustion, vehicles, and industrial activities, underscoring the significant health implications of the pollutants emitted from these sources. The study concluded that focusing solely on the mass reduction of PM2.5 may not suffice; a dual approach that reduces both mass concentration and chemical-specific health risks is imperative for effective public health protection.

Anti-photoaging effects of canola meal extract on human dermal fibroblasts against UVB-induced oxidative stress.

Canola meal, a by-product of canola oil processing, is a source of bioactive compounds that show antioxidant and skin anti-aging effects through upcycling (i.e., creative reuse). Here we describe the antioxidant and skin anti-aging effects of canola meal extract (CME) obtained by upcycling canola meal. The antioxidant capacity of CME is due in part to its antioxidative phenolics. Seven phenolics, including sinapine and sinapic acid, in CME were identified using ultra-high-performance liquid chromatography-Orbitrap mass spectrometry. Addition of CME (1000 µg/mL) to human dermal fibroblast neonatal cells  significantly (p < 0.05) reduced matrix metalloproteinase-12 production and increased pro-collagen Ι alpha 1 content in response to ultraviolet B-induced oxidative stress compared with cells without CME. These results suggest that CME can serve as a functional food ingredient with antioxidant capacity and anti-aging effects on the skin.

Effect of benzotriazole on the existing pits of copper tube in fire sprinkler system.

In this paper, two leaking tubes were investigated among copper tubes injected with 200 and 400 ppm benzotriazole after 8 years of usage. The electrochemical tests were conducted in simulated pit-out and pit-in environments (i.e., regions outside and inside of the pit) to determine the effect of benzotriazole on the propagation of an existing pit. The electrochemical analysis results showed that 200 and 400 ppm benzotriazole exhibit relatively lower inhibition efficiency in an acidic simulated pit-in environment because of the difficulty of forming a protective film and the benzotriazole cationization.

The impact of size-segregated particle properties on daily mortality in Seoul, Korea.

To investigate the causative component for certain health outcomes, the associations between the properties of ambient particles and cause-specific mortality (all-cause, cardiovascular, and respiratory-related mortality) measured in Seoul, Korea, from January 1, 2013, to December 31, 2016, were evaluated with a quasi-Poisson generalized additive model (GAM). The total mass of PM10 and PM2.5 moderately affected respiratory-related mortality but had almost no impact on all-cause and cardiovascular-related mortality. Among PM2.5 mass compositions, ammonium sulfate, which is in generally 300-500 nm as a secondary species, showed the most statistically significant effect on respiratory-related mortality at lag 4 (p < 0.1) but not for other mortalities. However, from the size-selective investigations, cardiovascular-related mortality was impacted by particle number concentrations (PNCs), particle surface concentrations (PSCs), and particle volume concentrations (PVCs) in the size range from 50 to 200 nm with a statistically significant association, particularly at lag 1, suggesting that mass is not the only way to examine mortality, which is likely because mass and chemical composition concentrations are generally controlled by larger-sized particles. Our study suggests that the size-specific mortality and/or impacts of size-resolved properties on mortalities need to be evaluated since smaller particles get into the body more efficiently, and therefore, more diverse size-dependent causes and effects can occur.

Seasonal characteristics of atmospheric water-soluble organic nitrogen in PM2.5 in Seoul, Korea: Source and atmospheric processes of free amino acids and aliphatic amines.

The seasonal characteristics of atmospheric water-soluble organic nitrogen (WSON) in particulate matter with a diameter of 2.5 µm or smaller (PM2.5) were analyzed focusing on sources and atmospheric processing. Daily collected samples over 23 h (10:00-9:00) from 7 August 2018 to 31 December 2019 on quartz filters with a high-volume sampler at the Korea Institute of Science and Technology (KIST) in Seoul were considered. The most common species in the Seoul atmosphere included Glycine (5.45 ± 9.81 ng/m3) among free amino acids (FAAs) and trimethylamine (TMA) (5.35 ± 3.80 ng/m3) among aliphatic amines (AAs). The top 10 WSON species (93.6% of all WSON species) were categorized into three groups based on correlation analysis considering meteorological data, (e.g., temperature, rainfall, relative humidity (RH), wind speed) gaseous pollutants (e.g., SO2, CO, NO2) and mass concentration of PM10 and PM2.5. Those three groups are G1 (Glycine, Alanine, and Threonine), G2 (Gln Glutamine, Lys Lysine, and Glutamic acid) and G3 (Trimethylamine (TMA), dimethylamine (DMA), and methylamine (MA)), where G1, G2 and G3 accounted for 31.1%, 8.8% and 51.1%, respectively, of the total species. Among these three groups, G1 and G3 are from combustion sources, and G2 shows secondary features generated by photochemical reactions involving ozone. Although both G1 and G3 exhibited features influenced by combustion sources, the AA species (TMA, DMA, and MA) in G3 demonstrated typical features enhanced under high-humidity conditions, suggesting not only primary sources but also secondary formation at the local scale influence to the AA in G3 group. Based on long-term measurements more than a year, our findings suggest that complex and diverse sources of atmospheric WSON are in Seoul, Korea both from primary and secondary, which may affect its environmental, climate and health.

Respiratory function declines in children with asthma associated with chemical species of fine particulate matter (PM2.5) in Nagasaki, Japan.

BACKGROUND: The differential effects of PM2.5 fractions on children's lung function remain inconclusive. This study aimed to examine whether lung function in asthmatic children was associated with increased PM2.5 fractions in urban areas in Nagasaki prefecture, Japan, where the air pollution level is relatively low but influenced by transboundary air pollution. METHODS: We conducted a multiyear panel study of 73 asthmatic children (boys, 60.3%; mean age, 8.2 years) spanning spring 2014-2016 in two cities. We collected self-measured peak expiratory flow (PEF) twice a day and daily time-series data for PM2.5 total mass and its chemical species. We fitted a linear mixed effects model to examine short-term associations between PEF and PM2.5, adjusting for individual and time-varying confounders. A generalized linear mixed effects model was also used to estimate the association for worsening asthma defined by severe PEF decline. Back-trajectory and cluster analyses were used to investigate the long-range transboundary PM2.5 in the study areas. RESULTS: We found that morning PEFs were adversely associated with higher levels of sulfate (- 1.61 L/min; 95% CI: - 3.07, - 0.15) in Nagasaki city and organic carbon (OC) (- 1.02 L/min; 95% CI: - 1.94, - 0.09) in Isahaya city, per interquartile range (IQR) increase at lag1. In addition, we observed consistent findings for worsening asthma, with higher odds of severe PEF decline in the morning for sulfate (odds ratio (OR) = 2.31; 95% CI: 1.12, 4.77) and ammonium (OR = 1.73; 95% CI: 1.06, 2.84) in Nagasaki city and OC (OR = 1.51; 95% CI: 1.06, 2.15) in Isahaya city, per IQR increase at lag1. The significant chemical species were higher on days that could be largely attributed to the path of Northeast China origin (for sulfate and ammonium) or both the same path and local sources (for OC) than by other clusters. CONCLUSIONS: This study provides evidence of the differential effects of PM2.5 fractions on lung function among asthmatic children in urban areas, where the Japanese national standards of air quality have been nearly met. Continuous efforts to promote mitigation actions and public awareness of hazardous transboundary air pollution are needed to protect susceptible children with asthma.

The major chemical constituents of PM2.5 and airborne bacterial community phyla in Beijing, Seoul, and Nagasaki.

Ambient particle (PM2.5) samples were collected in three East Asian cities (Beijing, China; Seoul, South Korea; Nagasaki, Japan) from December 2014 to November 2015 to quantitatively investigate airborne bacteria at the phylum level. Proteobacteria, Firmicutes, Actinobacteria, Bacteroidetes, and Cyanobacteria represented the top five airborne bacterial phyla in all three cities. The most dominant airborne phylum, Proteobacteria, was more prevalent during the winter (at rates of 67.2%, 79.9%, and 87.0% for Beijing, Seoul, and Nagasaki, respectively). Correlations among airborne bacteria and environmental factors including PM2.5, its major chemical constituents, and meteorological factors were calculated. Temperature correlated negatively with Proteobacteria but positively with Firmicutes and Bacteroidetes. The abundance of Cyanobacteria correlated positively with particulate NO3- and SO42- levels in Beijing (R = 0.46 and R = 0.35 for NO3- and SO42-, respectively) but negatively in Seoul (R = -0.14 and R = -0.19 for NO3- and SO42-, respectively) and Nagasaki (R = -0.05 and R = -0.03 for NO3- and SO42-, respectively). Backward trajectory analysis was applied for 72 h and three clusters were classified in each city. Five dominant bacteria and other bacterial groups showed significant differences (p < 0.05) in local clustering, as compared to the long-range transport clusters from Beijing. The proportions of the five bacterial phyla in Seoul were significantly different in each cluster. A local cluster in Nagasaki had higher ratios of all major airborne bacterial phyla, except Proteobacteria.

Long term trends of chemical constituents and source contributions of PM2.5 in Seoul.

PM2.5 was measured and analyzed between 2014 and 2015 in Seoul, and its sources were identified with a positive matrix factorization (PMF) to characterize chemical constituents and sources of the measured PM2.5. To verify policy interventions in reducing PM2.5 levels in Korea, the results were compared with previously published results from 2003 to 2007 at the same study site. A total of 215 PM2.5 samples were collected and analyzed for 24 species, i.e., carbonaceous species (OCEC), ionic species (NO3-, SO42-, and NH4+), and 19 element species in this study. The average PM2.5 mass concentration during the sampling period was 42.6±23.3 µg m-3. The seasonal average mass concentration of PM2.5 was the highest during winter (49.9±20.6 µg m-3), followed by spring (45.2±25.3 µg m-3), fall (34.4±19.3 µg m-3), and summer (28.4±12.5 µg m-3). Nine sources were identified and quantified using the PMF model: secondary nitrate (19.0%), secondary sulfate (20.2%), mobile (23.3%), biomass burning (12.1%), soil (8.3%), roadway emissions (3.1%), aged sea salt (1.0%), coal combustion (4.1%), and oil combustion (9.0%). The PM2.5 levels and chemical constituents during this study were lower than those during the previous study from 2003 to 2007. Particularly, concentrations of mobile related chemicals (OC, EC, and nitrate) and mobile source contributions consistently decreased from 2003 to 2015, indicating that the mobile emission reduction policy is improving PM2.5 levels in the region. The comparison between the two periods allows trends in chemical constituents and the sources of PM2.5 in Seoul to be understood.

Comparisons of doxycycline solution with talc slurry for chemical pleurodesis and risk factors for recurrence in South Korean patients with spontaneous pneumothorax.

PURPOSE: Talc slurry (TS) has been commonly used with high success rates in managing spontaneous pneumothroax (SP), but there were concerns of post-procedural complications. Alternatively, doxycycline solution (DS) was used successfully. This retrospective study aims to compare the effectiveness and safety between talc and doxycycline as a sclerosing agent and to investigate risk factors for recurrence in patients with SP. METHODS: The review of medical records between January 2011 and December 2014 was conducted on 83 patients with SP who underwent pleurodesis with either TS (n=16) or DS (n=67). Recurrence and complications were compared between the DS and TS groups. Associations between recurrence after DS treatment and various factors were analysed. RESULTS: Recurrence was significantly higher in the DS group than in the TS group (P=0.033), whereas complications were higher in the TS group than the DS group: fever was significantly higher in the TS group (P=0.001). Recurrences associated with doxycycline use were found significantly more often in patients with recurrent diagnosis of SP, height/weight ≥3.25 cm/kg and weight <55 kg. CONCLUSION: Talc was more effective without recurrence compared with doxycycline. Clinically insignificant fever associated with pleurodesis was more common with talc. Low weight, high height to weight ratio and recurrent diagnosis of SP were associated with higher recurrence after doxycycline treatment.

Reactive oxygen species (ROS) activity of ambient fine particles (PM2.5) measured in Seoul, Korea.

Substantial increase in level of particulate matter has raised concerns in South Korea recently. Ambient particulate matter is classified as Group I carcinogen (IARC, 2013) and multiple epidemiological studies has demonstrated adverse health effects due to exposure of particulate matter. Fine particulate matter (PM2.5) which has a diameter <2.5 µm is likely to penetrate deeply into lung and is known to be eliciting adverse health effects. A number of epidemiological studies have been conducted on adverse health effects of PM-related diseases and mortality rate, yet particulate matter (PM)-induced reactive oxygen species (ROS) activity at the cellular level has not been actively studied in Korea. This study assessed PM-induced oxidative potential by exposure of collected ambient PM2.5 samples to the rat alveolar macrophage cell line. The characteristics of PM2.5 in Korea were further characterized by linking chemical constituents and contributing sources to ROS. PM2.5 mass concentration during the cold season was relatively higher than mass concentration during the warm season and chemical constituents except for Secondary Organic Carbon (SOC) and SO42- which both showed similar trends in both the cold and cold seasons. The concentration of crustal elements was especially high during the cold season which can be an indication of long range transport of Asian dust. Water soluble organic carbon and water soluble transition metals (Cr and Zn) were also shown to be correlated to oxidative potential and metals such as As and V were shown to have a high contribution to ROS activity according to stepwise multiple linear regression. Principal Component Analysis (PCA) results identified six factors that can be interpreted as soil, mobile, industry, secondary inorganic aerosol, secondary organic aerosol and oil combustion. Moreover, through Principal Component Regression (PCR), industry, soil, mobile and SIA were shown to be statistically significant sources in a relation to ROS activity.

Airborne Bacterial Communities in Three East Asian Cities of China, South Korea, and Japan.

The global diversity of airborne bacteria has not yet been studied, despite its importance in human health and climate change. Here, we focused on the diversity of airborne bacteria and their correlations with meteorological/environmental conditions in China, South Korea, and Japan. Beijing (China) had more diverse airborne bacteria, followed by Seoul (South Korea) and Nagasaki (Japan), and seasonal variations were observed. Beijing and Seoul had more diverse airborne bacteria during the winter, whereas Nagasaki showed greater diversity during the summer. According to principal component analysis and Bray-Curtis similarity, higher similarity was observed between Beijing and Seoul than between Seoul and Nagasaki during all seasons except summer. Among meteorological/environmental variables, temperature and humidity were highly correlated with the diversity of airborne bacteria on the measurement day, whereas wind speeds and the frequency of northwest winds were highly correlated for 2-3-day moving averages. Thus, proximity and resuspension could enhance bacterial diversity in East Asian cities.

Age-specific prevalence of serrated lesions and their subtypes by screening colonoscopy: a retrospective study.

BACKGROUND: Serrated lesions of the colorectum as categorized by pathology include hyperplastic polyps, sessile serrated adenomas without dysplasia, and traditional serrated adenomas with dysplasia. The aim of this study was to investigate the prevalence of various subtypes of serrated lesions by age. METHODS: In this study, 28,544 consecutive asymptomatic patients (aged 22-88 years) were evaluated during health check-ups involving colonoscopies performed by gastroenterologists at a single institution from 2005 to 2012. RESULTS: The adenoma detection rate during colonoscopies for patients aged ≥50 years was 31.8% (25.0-35.8%). The serrated lesion detection rate for patients aged ≥50 years was 15.3% (10.5-19.6%). Serrated lesions were detected in 15.1% of all patients with subtype prevalences of 14.7% for hyperplastic polyps, 0.5% for sessile serrated adenomas, and 0.1% for traditional serrated adenomas. The prevalence of conventional adenomas increased sharply with age (5.0% in patients aged 20-29 years, 10.9% in those aged 30-39 years, 21.8% in those aged 40-49 years, 29.5% in those aged 50-59 years, 36.9% in those aged 60-69 years, and 40.7% in those aged ≥70 years) (trend P = 0.027). In contrast, the prevalence of serrated lesions increased only slightly with age (10.0% in patients aged 20-29 years, 11.8% in those aged 30-39 years, 14.8% in those aged 40-49 years, 15.3% in those aged 50-59 years, 16.8% in those aged 60-69 years, and 16.4% in those aged ≥70 years) (trend P = 0.036). CONCLUSIONS: The screening colonoscopy detection rate of serrated lesions, including sessile serrated adenomas and traditional serrated adenomas, appears to be relatively high among young patients aged <50 years.

Prevalence and risk factors of functional dyspepsia: a nationwide multicenter prospective study in Korea.

GOALS: To evaluate the prevalence of functional dyspepsia (FD) and its risk factors. BACKGROUND: FD is a common disorder, but its negative influences greatly affect the quality of life. The predictive factors of FD are still ambiguous. STUDY: A total of 3399 participants underwent screening gastroscopy at one of 7 nationwide health care centers in Korea and who completed a questionnaire. Atrophic gastritis was defined by gastroscopy. Serologic Helicobacter pylori immunoglobulin G antibody was measured by enzyme-linked immunosorbent assay. RESULTS: Of the 3399 participants who did not have organic diseases, 694 (20.4%) had dyspeptic symptoms such as epigastric pain/soreness or postprandial discomfort. Among the 694 participants, atrophic gastritis and positive H. pylori serology were found in 282 (40.6%) and 422 (60.8%), respectively; these proportions were not different from the remaining asymptomatic subjects. Multivariate analysis showed that having relatives with gastric cancer [odds ratio (OR), 1.35; 95% confidence interval (CI), 1.01-1.81], education below college (OR, 1.32; 95% CI, 1.06-1.64), and high-salt diet (OR, 1.33; 95% CI, 1.05-1.68) were associated with FD symptoms. CONCLUSIONS: FD symptoms were frequently found in the health check-up subjects. Relatives of gastric cancer, education below college, and high-salt diet were risk factors of FD, suggesting that FD is a multifactorial disease.

Seroprevalence of Helicobacter pylori Infection in Korean Health Personnel.

BACKGROUND/AIMS: The aims of this study were to evaluate whether doctors and nurses in a single hospital were at an increased risk of acquiring Helicobacter pylori infection in 2011 and to identify risk factors for H. pylori seroprevalence. METHODS: Nurses (n=362), doctors (n=110), health personnel without patient contact (medical control, n=179), and nonhospital controls (n=359) responded to a questionnaire during a health check-up, which included questions on socioeconomic status, education level, working years, and occupation in 2011. The prevalence of H. pylori was measured by serology. RESULTS: The seroprevalence rate was 29.8% (nurses), 34.5% (doctors), 30.7% (medical control), and 52.9% (nonhospital control). Among younger subjects (<40 years of age), the nonhospital control had a higher seropositivity rate (48.1%) than nurses (29.2%), doctors (29.8%), and the medical control (24.8%), which was not observable in subjects ≥40 years of age. The risk factors for H. pylori seroprevalence were not different for health and nonhealth personnel. A multivariate analysis indicated that seropositivity significantly increased with age, the province of residence, and a gastroscopic finding of a peptic ulcer. CONCLUSIONS: The medical occupation was not associated with H. pylori infection. The seroprevalence of H. pylori in one hospital in 2011 was found to be 38.7%, most likely due to the improvement in socioeconomic status and hospital hygiene policy in Korea.

Nonalcoholic fatty liver disease is associated with coronary artery calcification.

UNLABELLED: Nonalcoholic fatty liver disease (NAFLD) is related to risk factors of coronary artery disease, such as dyslipidemia, diabetes, and metabolic syndrome, which are closely linked with visceral adiposity. The aim of this study was to investigate whether NAFLD was associated with coronary artery calcification (CAC), which is used as a surrogate marker for coronary atherosclerosis independent of computed tomography (CT)-measured visceral adiposity. Out of 5,648 subjects who visited one of our health screening centers between 2003 and 2008, we enrolled 4,023 subjects (mean age, 56.9 ± 9.4 years; 60.7% males) without known liver disease or a history of ischemic heart disease. CAC score was evaluated using the Agatston method. On univariate analysis, the presence of CAC (score >0) was significantly associated with age, sex, body mass index, aspartate aminotransferase, alanine aminotransferase, high-density lipoprotein cholesterol, triglycerides, and increased risk of diabetes, hypertension, smoking, and NAFLD. Increasing CAC scores (0, <10, 10-100, ≥ 100) were associated with higher prevalence of NAFLD (odds ratio [OR], 1.84; 95% confidence interval [CI], 1.61-2.10; P<0.001). Multivariable ordinal regression analysis was adjusted for traditional risk factors, and CT-measured visceral adipose tissue area in a subgroup of subjects showed that the increased CAC scores were significantly associated with the presence of NAFLD (OR, 1.28, 95% CI, 1.04-1.59; P = 0.023) independent of visceral adiposity. CONCLUSION: Patients with NAFLD are at increased risk for coronary atherosclerosis independent of classical coronary risk factors, including visceral adiposity. These data suggest that NAFLD might be an independent risk factor for coronary artery disease.

Effects of different dilutions of botulinum toxin type A treatment for children with cerebral palsy with spastic ankle plantarflexor: a randomized controlled trial.

OBJECTIVE: The aim of this study was to investigate the influence of different volumes of saline vehicle on the effects of botulinum toxin type A in reducing ankle plantarflexor spasticity and improving gait pattern in children with cerebral palsy. DESIGN: Children with cerebral palsy having ankle plantarflexor spasticity were recruited. They were divided randomly into 2 groups. Botulinum toxin type A mixed with 2 ml or 8 ml saline was injected into the gastrocnemius in each group. Passive range of movement of ankle joint, Modified Ashworth Scale, and results of 3-dimensional motion analysis obtained at pre-treatment, 4, 12, and 24 weeks after treatment were compared. RESULTS: Ankle dorsiflexion was increased and ankle plantarflexor spasticity was decreased significantly after botulinum toxin type A treatment. Linear parameters were generally improved, and these improvements persisted until 12-24 weeks. The ankle dorsiflexion angle in the stance phase was also increased, and this increase was maintained until 24 weeks, as revealed by 3-dimensional gait analysis. However, no significantly different effect of varying the amount of saline vehicle was detected. CONCLUSION: Botulinum toxin type A improved physical findings and gait pattern in patients with cerebral palsy. The volume of saline mixed with botulinum toxin type A did not result in significant differences in physical evaluation or gait analysis. However, the large-volume group revealed side-effects more frequently and showed no clinical benefits compared with the small-volume group. We conclude that 2 ml of dilution is preferable for botulinum toxin type A treatment in children.

Clinical outcome of rumination syndrome in adults without psychiatric illness: a prospective study.

BACKGROUND AND AIM: This prospective study was conducted to characterize the clinical features of adult rumination syndrome, in the absence of psychiatric illness, by applying newly modified clinical criteria, and to elucidate factors influencing outcomes after treatment. METHODS: Twenty-one adult patients diagnosed with rumination syndrome at a tertiary referral center over a 2-year period were enrolled in the study. All patients received supportive psychotherapy and medical treatment. Changes in symptom parameters were analyzed using a pretreatment and a post-treatment questionnaire. Patients were classified into three groups according to symptomatic outcome: improved group, sustained group and aggravated group. RESULTS: The duration of treatment was longer in the improved group than in the sustained or aggravated groups (P = 0.018). Esophageal manometry testing demonstrated non-transmitted contractions of the esophageal body in 10 patients (47.6%) and low amplitude contractions in eight patients (38.1%). Mean lower esophageal sphincter (LES) pressure was 9.8 +/- 2.6 mmHg. Baseline LES pressure in the improved group was higher than in the other groups (P = 0.001). Ambulatory 24-h esophageal pH monitoring showed pathological acid reflux in six patients (28.6%). All pathological acid reflux occurred in post-rumination periods. Scintigraphic testing of gastric emptying revealed that the mean retention rate at 120 min was 34.2 +/- 2.5% of initial contents, and delayed emptying was noted in three patients (14.3%). CONCLUSIONS: Rumination syndrome is often accompanied by heterogeneous conditions such as postprandial gastroesophageal reflux, various abnormalities in esophageal manometric tests and delayed gastric emptying. Medical treatment and supportive psychotherapy can be effective in otherwise normal adult patients, especially in patients who comply with long durations of treatment and who demonstrate higher baseline LES pressures.

Clinical usefulness of subgrouping of patients with non-cardiac chest pain according to characteristic symptoms in Korea.

BACKGROUND: Non-cardiac chest pain (NCCP) is a heterogeneous disorder. There is controversy about the associations between symptoms and causes in NCCP patients. The purpose of the present study was to evaluate the clinical usefulness of subgrouping according to characteristic symptoms in NCCP patients. PATIENTS AND METHODS: Fifty-eight patients were classified into two groups, as patients with typical reflux symptoms (group I, n = 24) and those without typical reflux symptoms (group II, n = 34). They underwent upper endoscopy, manometry, and 24-h esophageal pH monitoring. RESULTS: Twenty-four (41%) of the patients were diagnosed with gastroesophageal reflux disease (GERD) at upper endoscopy or 24-h esophageal pH monitoring. Eleven (19%) were diagnosed with GERD-associated esophageal motility disorder and 13 (22%) were diagnosed with non-GERD-associated esophageal motility disorder. The two groups did not differ significantly in age, sex, weight, smoking history, history of chronic alcoholism, or the severity, duration and frequency of symptoms. The sensitivity, specificity, positive predictive value, negative predictive value, and likelihood ratio of group I for GERD-related NCCP were significantly higher than those of group II. Group I had a higher proportion of patients with GERD-associated esophageal motility disorder (55%) than non-GERD-associated esophageal motility disorder (23%). CONCLUSION: Typical reflux symptoms can be used to distinguish patients with GERD-related NCCP from patients with NCCP, and subgrouping according to characteristic symptoms may assist the diagnosis of these patients in Korea.

Autologous allogeneic amniotic membrane grafting in Stevens-Johnson syndrome.

We describe the use of autologous allogeneic amniotic membrane in ocular surface reconstruction. A 28-year-old woman with cicatricial entropion from Stevens-Johnson syndrome had recurrent keratinization of the tarsal conjunctiva. Amniotic membrane from the patient's own conceptus was stored and successfully used in ocular surface reconstruction with improvement of ocular symptoms. Disease transmission is an important risk inherent in all human tissue transplantation. Use of carefully prepared autologous allogeneic amniotic membrane grafts should be considered in pregnant patients in need of ocular surface reconstruction.

Twenty-four-hour pattern of intraocular pressure in young adults with moderate to severe myopia.

PURPOSE: To characterize the 24-hour change of intraocular pressure (IOP) in young adults with moderate to severe myopia. METHODS: Nineteen young adults, ages 18 to 25 years, with moderate to severe myopia (myopia group) and 17 age-matched volunteers with emmetropia or mild myopia (control group) were housed for 1 day in a sleep laboratory. An 8-hour accustomed sleep period was assigned to each volunteer. Twelve measurements of IOP, axial length, blood pressure, and heart rate were taken at 2-hour intervals. In the wake period, blood pressure and heart rate were measured after a 5-minute bed rest. Axial length and IOP were measured in supine volunteers. Volunteers then sat for 5 minutes, after which IOP was measured. In the sleep period, measurements were taken in supine volunteers in bed. RESULTS: In both the myopia and control groups, the average supine IOP in the sleep period was higher than the average sitting IOP in the wake period. However, the magnitude of this IOP elevation at night was significantly less in the myopia group. In the sleep period, IOP was less in the myopia group than in the control group. When only the 24-hour supine IOP data were considered, the trough occurred at 1:30 AM, and the peak occurred around noon in the myopia group. In the control group, the trough was at 9:30 PM, and the peak at 5:30 AM. Least-square cosine fits showed 24-hour rhythms of supine IOP in both groups, but their phase timings were different. Axial length remained unchanged throughout the day and night in both groups. There was no difference in the 24-hour rhythms of mean blood pressure and heart rate between the two groups. CONCLUSIONS: Considering habitual body positions, IOP increases at night in young adults with moderate to severe myopia, but the magnitude of the increase is significantly less than that in the age-matched control subjects. There is a 24-hour rhythm of supine IOP in the myopic group, but the phase timing is different from that in the control subjects. These variations of IOP in young adults with moderate to severe myopia are not related to changes in cardiovascular parameters.